From 172b0eb9bebad1153acf3e4cd149e1a71cb6fe5d Mon Sep 17 00:00:00 2001
From: steven_q
As well as Perl-style regular expression patterns, some features that appeared @@ -38,8 +39,14 @@ Oniguruma syntax items, and there are options for requesting some minor changes that give better ECMAScript (aka JavaScript) compatibility.
-The source code for PCRE2 can be compiled to support 8-bit, 16-bit, or 32-bit -code units, which means that up to three separate libraries may be installed. +The source code for PCRE2 can be compiled to support strings of 8-bit, 16-bit, +or 32-bit code units, which means that up to three separate libraries may be +installed, one for each code unit size. The size of code unit is not related to +the bit size of the underlying hardware. In a 64-bit environment that also +supports 32-bit applications, versions of PCRE2 that are compiled in both +64-bit and 32-bit modes may be needed. +
+The original work to extend PCRE to 16-bit and 32-bit code units was done by Zoltan Herczeg and Christian Persch, respectively. In all three cases, strings can be interpreted either as one character per code unit, or as UTF-encoded @@ -187,20 +194,20 @@ function, listing its arguments and results.
Philip Hazel
-University Computing Service
+Retired from University Computing Service
Cambridge, England.
Putting an actual email address here is a spam magnet. If you want to email me, -use my two initials, followed by the two digits 10, at the domain cam.ac.uk. +use my two names separated by a dot at gmail.com.
-Last updated: 17 September 2018
+Last updated: 27 August 2021
-Copyright © 1997-2018 University of Cambridge.
+Copyright © 1997-2021 University of Cambridge.
Return to the PCRE2 index page. diff --git a/pcre2/doc/html/pcre2_dfa_match.html b/pcre2/doc/html/pcre2_dfa_match.html index 232e2bc..0ae428c 100644 --- a/pcre2/doc/html/pcre2_dfa_match.html +++ b/pcre2/doc/html/pcre2_dfa_match.html @@ -45,10 +45,16 @@ just once (except when processing lookaround assertions). This function is workspace Points to a vector of ints used as working space wscount Number of elements in the vector -For pcre2_dfa_match(), a match context is needed only if you want to set -up a callout function or specify the heap limit or the match or the recursion -depth limits. The length and startoffset values are code units, not -characters. The options are: +The size of output vector needed to contain all the results depends on the +number of simultaneous matches, not on the number of parentheses in the +pattern. Using pcre2_match_data_create_from_pattern() to create the match +data block is therefore not advisable when using this function. +
++A match context is needed only if you want to set up a callout function or +specify the heap limit or the match or the recursion depth limits. The +length and startoffset values are code units, not characters. The +options are:
PCRE2_ANCHORED Match only at the first position PCRE2_COPY_MATCHED_SUBJECT diff --git a/pcre2/doc/html/pcre2_match_data_create.html b/pcre2/doc/html/pcre2_match_data_create.html index 8d0321b..c26c3b3 100644 --- a/pcre2/doc/html/pcre2_match_data_create.html +++ b/pcre2/doc/html/pcre2_match_data_create.html @@ -30,8 +30,9 @@ This function creates a new match data block, which is used for holding the result of a match. The first argument specifies the number of pairs of offsets that are required. These form the "output vector" (ovector) within the match data block, and are used to identify the matched string and any captured -substrings. There is always one pair of offsets; if ovecsize is zero, it -is treated as one. +substrings when matching with pcre2_match(), or a number of different +matches at the same point when used with pcre2_dfa_match(). There is +always one pair of offsets; if ovecsize is zero, it is treated as one.Any substring (including the executable name) may contain escape sequences -started by a dollar character: $<digits> or ${<digits>} is replaced by the -captured substring of the given decimal number, which must be greater than -zero. If the number is greater than the number of capturing substrings, or if -the capture is unset, the replacement is empty. - -The second argument points to a general context, for custom memory management, diff --git a/pcre2/doc/html/pcre2_match_data_create_from_pattern.html b/pcre2/doc/html/pcre2_match_data_create_from_pattern.html index f40cf1e..4836474 100644 --- a/pcre2/doc/html/pcre2_match_data_create_from_pattern.html +++ b/pcre2/doc/html/pcre2_match_data_create_from_pattern.html @@ -26,12 +26,15 @@ SYNOPSIS DESCRIPTION
-This function creates a new match data block, which is used for holding the -result of a match. The first argument points to a compiled pattern. The number -of capturing parentheses within the pattern is used to compute the number of -pairs of offsets that are required in the match data block. These form the -"output vector" (ovector) within the match data block, and are used to identify -the matched string and any captured substrings. +This function creates a new match data block for holding the result of a match. +The first argument points to a compiled pattern. The number of capturing +parentheses within the pattern is used to compute the number of pairs of +offsets that are required in the match data block. These form the "output +vector" (ovector) within the match data block, and are used to identify the +matched string and any captured substrings when matching with +pcre2_match(). If you are using pcre2_dfa_match(), which uses the +outut vector in a different way, you should use pcre2_match_data_create() +instead of this function.
The second argument points to a general context, for custom memory management, diff --git a/pcre2/doc/html/pcre2_set_compile_extra_options.html b/pcre2/doc/html/pcre2_set_compile_extra_options.html index c6c11f7..b1c0a11 100644 --- a/pcre2/doc/html/pcre2_set_compile_extra_options.html +++ b/pcre2/doc/html/pcre2_set_compile_extra_options.html @@ -30,7 +30,8 @@ This function sets additional option bits for pcre2_compile() that are housed in a compile context. It completely replaces all the bits. The extra options are:
- PCRE2_EXTRA_ALLOW_SURROGATE_ESCAPES Allow \x{df800} to \x{dfff} in UTF-8 and UTF-32 modes + PCRE2_EXTRA_ALLOW_LOOKAROUND_BSK Allow \K in lookarounds PCRE2_EXTRA_ALLOW_SURROGATE_ESCAPES Allow \x{df800} to \x{dfff} + in UTF-8 and UTF-32 modes PCRE2_EXTRA_ALT_BSUX Extended alternate \u, \U, and \x handling PCRE2_EXTRA_BAD_ESCAPE_IS_LITERAL Treat all invalid escapes as a literal following character PCRE2_EXTRA_ESCAPED_CR_IS_LF Interpret \r as \n diff --git a/pcre2/doc/html/pcre2api.html b/pcre2/doc/html/pcre2api.html index 36c2e3d..e2237e7 100644 --- a/pcre2/doc/html/pcre2api.html +++ b/pcre2/doc/html/pcre2api.html @@ -626,14 +626,15 @@ documentation for more details.-The \Q...\E sequence is recognized both inside and outside character classes. +The \Q...\E sequence is recognized both inside and outside character classes +by both PCRE2 and Perl.In a more complicated situation, where patterns are compiled only when they are first needed, but are still shared between threads, pointers to compiled -patterns must be protected from simultaneous writing by multiple threads, at -least until a pattern has been compiled. The logic can be something like this: +patterns must be protected from simultaneous writing by multiple threads. This +is somewhat tricky to do correctly. If you know that writing to a pointer is +atomic in your environment, you can use logic like this:
Get a read-only (shared) lock (mutex) for pointer if (pointer == NULL) { Get a write (unique) lock for pointer - pointer = pcre2_compile(... + if (pointer == NULL) pointer = pcre2_compile(... } Release the lock Use pointer in pcre2_match() @@ -641,10 +642,39 @@ least until a pattern has been compiled. The logic can be something like this: Of course, testing for compilation errors should also be included in the code.which finds occurrences of "iss" in the middle of words. (\B matches only if the current position in the subject is not a word boundary.) When applied to -the string "Mississipi" the first call to pcre2_match() finds the first +the string "Mississippi" the first call to pcre2_match() finds the first occurrence. If pcre2_match() is called again with just the remainder of -the subject, namely "issipi", it does not match, because \B is always false at -the start of the subject, which is deemed to be a word boundary. However, if +the subject, namely "issippi", it does not match, because \B is always false +at the start of the subject, which is deemed to be a word boundary. However, if pcre2_match() is passed the entire string again, but with startoffset set to 4, it finds the second occurrence of "iss" because it is able to look behind the starting point to discover that it is preceded by a @@ -3949,16 +4001,16 @@ fail, this error is given.-If JIT is being used, but the JIT compilation is not being done immediately, -(perhaps waiting to see if the pattern is used often enough) similar logic is -required. JIT compilation updates a pointer within the compiled code block, so -a thread must gain unique write access to the pointer before calling +The reason for checking the pointer a second time is as follows: Several +threads may have acquired the shared lock and tested the pointer for being +NULL, but only one of them will be given the write lock, with the rest kept +waiting. The winning thread will compile the pattern and store the result. +After this thread releases the write lock, another thread will get it, and if +it does not retest pointer for being NULL, will recompile the pattern and +overwrite the pointer, creating a memory leak and possibly causing other +issues. +
++In an environment where writing to a pointer may not be atomic, the above logic +is not sufficient. The thread that is doing the compiling may be descheduled +after writing only part of the pointer, which could cause other threads to use +an invalid value. Instead of checking the pointer itself, a separate "pointer +is valid" flag (that can be updated atomically) must be used: +
+ Get a read-only (shared) lock (mutex) for pointer + if (!pointer_is_valid) + { + Get a write (unique) lock for pointer + if (!pointer_is_valid) + { + pointer = pcre2_compile(... + pointer_is_valid = TRUE + } + } + Release the lock + Use pointer in pcre2_match() ++If JIT is being used, but the JIT compilation is not being done immediately +(perhaps waiting to see if the pattern is used often enough), similar logic is +required. JIT compilation updates a value within the compiled code block, so a +thread must gain unique write access to the pointer before calling pcre2_jit_compile(). Alternatively, pcre2_code_copy() or pcre2_code_copy_with_tables() can be used to obtain a private copy of the compiled code before calling the JIT compiler. @@ -1492,10 +1522,13 @@ letters in the subject. It is equivalent to Perl's /i option, and it can be changed within a pattern by a (?i) option setting. If either PCRE2_UTF or PCRE2_UCP is set, Unicode properties are used for all characters with more than one other case, and for all characters whose code points are greater than -U+007F. For lower valued characters with only one other case, a lookup table is -used for speed. When neither PCRE2_UTF nor PCRE2_UCP is set, a lookup table is -used for all code points less than 256, and higher code points (available only -in 16-bit or 32-bit mode) are treated as not having another case. +U+007F. Note that there are two ASCII characters, K and S, that, in addition to +their lower case ASCII equivalents, are case-equivalent with U+212A (Kelvin +sign) and U+017F (long S) respectively. For lower valued characters with only +one other case, a lookup table is used for speed. When neither PCRE2_UTF nor +PCRE2_UCP is set, a lookup table is used for all code points less than 256, and +higher code points (available only in 16-bit or 32-bit mode) are treated as not +having another case.PCRE2_DOLLAR_ENDONLY@@ -1881,6 +1914,13 @@ Extra compile optionsThe option bits that can be set in a compile context by calling the pcre2_set_compile_extra_options() function are as follows: +
+ PCRE2_EXTRA_ALLOW_LOOKAROUND_BSK ++Since release 10.38 PCRE2 has forbidden the use of \K within lookaround +assertions, following Perl's lead. This option is provided to re-enable the +previous behaviour (act in positive lookarounds, ignore in negative ones) in +case anybody is relying on it.PCRE2_EXTRA_ALLOW_SURROGATE_ESCAPES@@ -2479,20 +2519,31 @@ to an abstract format like Java or .NET serialization. Information about a successful or unsuccessful match is placed in a match data block, which is an opaque structure that is accessed by function calls. In particular, the match data block contains a vector of offsets into the subject -string that define the matched part of the subject and any substrings that were -captured. This is known as the ovector. +string that define the matched parts of the subject. This is known as the +ovector.Before calling pcre2_match(), pcre2_dfa_match(), or pcre2_jit_match() you must create a match data block by calling one of the creation functions above. For pcre2_match_data_create(), the first -argument is the number of pairs of offsets in the ovector. One pair of -offsets is required to identify the string that matched the whole pattern, with -an additional pair for each captured substring. For example, a value of 4 -creates enough space to record the matched portion of the subject plus three -captured substrings. A minimum of at least 1 pair is imposed by -pcre2_match_data_create(), so it is always possible to return the overall -matched string. +argument is the number of pairs of offsets in the ovector. +
++When using pcre2_match(), one pair of offsets is required to identify the +string that matched the whole pattern, with an additional pair for each +captured substring. For example, a value of 4 creates enough space to record +the matched portion of the subject plus three captured substrings. +
++When using pcre2_dfa_match() there may be multiple matched substrings of +different lengths at the same point in the subject. The ovector should be made +large enough to hold as many as are expected. +
++A minimum of at least 1 pair is imposed by pcre2_match_data_create(), so +it is always possible to return the overall matched string in the case of +pcre2_match() or the longest match in the case of +pcre2_dfa_match().
The second argument of pcre2_match_data_create() is a pointer to a @@ -2503,10 +2554,11 @@ pass NULL, which causes malloc() to be used.
For pcre2_match_data_create_from_pattern(), the first argument is a pointer to a compiled pattern. The ovector is created to be exactly the right -size to hold all the substrings a pattern might capture. The second argument is -again a pointer to a general context, but in this case if NULL is passed, the -memory is obtained using the same allocator that was used for the compiled -pattern (custom or default). +size to hold all the substrings a pattern might capture when matched using +pcre2_match(). You should not use this call when matching with +pcre2_dfa_match(). The second argument is again a pointer to a general +context, but in this case if NULL is passed, the memory is obtained using the +same allocator that was used for the compiled pattern (custom or default).
A match data block can be used many times, with the same or different compiled @@ -2610,10 +2662,10 @@ lookbehind. For example, consider the pattern
Philip Hazel
-University Computing Service +Retired from University Computing Service
Cambridge, England.
REVISION
-Last updated: 19 March 2020 +Last updated: 30 August 2021
-Copyright © 1997-2020 University of Cambridge. +Copyright © 1997-2021 University of Cambridge.
Return to the PCRE2 index page. diff --git a/pcre2/doc/html/pcre2build.html b/pcre2/doc/html/pcre2build.html index a206b23..a1c2e95 100644 --- a/pcre2/doc/html/pcre2build.html +++ b/pcre2/doc/html/pcre2build.html @@ -553,15 +553,16 @@ documentation.
The C99 standard defines formatting modifiers z and t for size_t and ptrdiff_t values, respectively. By default, PCRE2 uses these modifiers in -environments other than Microsoft Visual Studio when __STDC_VERSION__ is -defined and has a value greater than or equal to 199901L (indicating C99). +environments other than old versions of Microsoft Visual Studio when +__STDC_VERSION__ is defined and has a value greater than or equal to 199901L +(indicating support for C99). However, there is at least one environment that claims to be C99 but does not support these modifiers. If
--disable-percent-ztis specified, no use is made of the z or t modifiers. Instead of %td or %zu, -%lu is used, with a cast for size_t values. +a suitable format is used depending in the size of long for the platform.
SUPPORT FOR FUZZERS
diff --git a/pcre2/doc/html/pcre2compat.html b/pcre2/doc/html/pcre2compat.html index 0c72a9a..eb82694 100644 --- a/pcre2/doc/html/pcre2compat.html +++ b/pcre2/doc/html/pcre2compat.html @@ -16,10 +16,10 @@ please consult the man page, in case the conversion went wrong. DIFFERENCES BETWEEN PCRE2 AND PERL
-This document describes the differences in the ways that PCRE2 and Perl handle -regular expressions. The differences described here are with respect to Perl -versions 5.26, but as both Perl and PCRE2 are continually changing, the -information may sometimes be out of date. +This document describes some of the differences in the ways that PCRE2 and Perl +handle regular expressions. The differences described here are with respect to +Perl version 5.32.0, but as both Perl and PCRE2 are continually changing, the +information may at times be out of date.
1. PCRE2 has only a subset of Perl's Unicode support. Details of what it does @@ -33,12 +33,15 @@ they do not mean what you might think. For example, (?!a){3} does not assert that the next three characters are not "a". It just asserts that the next character is not "a" three times (in principle; PCRE2 optimizes this to run the assertion just once). Perl allows some repeat quantifiers on other assertions, -for example, \b* (but not \b{3}), but these do not seem to have any use. +for example, \b* (but not \b{3}, though oddly it does allow ^{3}), but these +do not seem to have any use. PCRE2 does not allow any kind of quantifier on +non-lookaround assertions.
3. Capture groups that occur inside negative lookaround assertions are counted, but their entries in the offsets vector are set only when a negative assertion is a condition that has a matching branch (that is, the condition is false). +Perl may set such capture groups in other circumstances.
4. The following Perl escape sequences are not supported: \F, \l, \L, \u, @@ -56,10 +59,12 @@ interprets them. built with Unicode support (the default). The properties that can be tested with \p and \P are limited to the general category properties such as Lu and Nd, script names such as Greek or Han, and the derived properties Any and L&. -PCRE2 does support the Cs (surrogate) property, which Perl does not; the Perl -documentation says "Because Perl hides the need for the user to understand the -internal representation of Unicode characters, there is no need to implement -the somewhat messy concept of surrogates." +Both PCRE2 and Perl support the Cs (surrogate) property, but in PCRE2 its use +is limited. See the +pcre2pattern +documentation for details. The long synonyms for property names that Perl +supports (such as \p{Letter}) are not supported by PCRE2, nor is it permitted +to prefix any of these properties with "Is".
6. PCRE2 supports the \Q...\E escape for quoting substrings. Characters @@ -79,7 +84,8 @@ other character. Note the following examples: \QA\B\E A\B A\B \Q\\E \ \\E
7. Fairly obviously, PCRE2 does not support the (?{code}) and (??{code}) @@ -94,13 +100,13 @@ to PCRE2 release 10.23, but from release 10.30 this changed, and backtracking into subroutine calls is now supported, as in Perl.
-9. If any of the backtracking control verbs are used in a group that is called -as a subroutine (whether or not recursively), their effect is confined to that -group; it does not extend to the surrounding pattern. This is not always the -case in Perl. In particular, if (*THEN) is present in a group that is called as -a subroutine, its action is limited to that group, even if the group does not -contain any | characters. Note that such groups are processed as anchored -at the point where they are tested. +9. In PCRE2, if any of the backtracking control verbs are used in a group that +is called as a subroutine (whether or not recursively), their effect is +confined to that group; it does not extend to the surrounding pattern. This is +not always the case in Perl. In particular, if (*THEN) is present in a group +that is called as a subroutine, its action is limited to that group, even if +the group does not contain any | characters. Note that such groups are +processed as anchored at the point where they are tested.
10. If a pattern contains more than one backtracking control verb, the first @@ -110,55 +116,58 @@ triggers (*PRUNE). Perl's behaviour is more complex; in many cases it is the same as PCRE2, but there are cases where it differs.
-11. Most backtracking verbs in assertions have their normal actions. They are -not confined to the assertion. -
--12. There are some differences that are concerned with the settings of captured +11. There are some differences that are concerned with the settings of captured strings when part of a pattern is repeated. For example, matching "aba" against the pattern /^(a(b)?)+$/ in Perl leaves $2 unset, but in PCRE2 it is set to "b".
-13. PCRE2's handling of duplicate capture group numbers and names is not as +12. PCRE2's handling of duplicate capture group numbers and names is not as general as Perl's. This is a consequence of the fact the PCRE2 works internally just with numbers, using an external table to translate between numbers and -names. In particular, a pattern such as (?|(?<a>A)|(?<b>B), where the two +names. In particular, a pattern such as (?|(?<a>A)|(?<b>B)), where the two capture groups have the same number but different names, is not supported, and causes an error at compile time. If it were allowed, it would not be possible to distinguish which group matched, because both names map to capture group number 1. To avoid this confusing situation, an error is given at compile time.
-14. Perl used to recognize comments in some places that PCRE2 does not, for +13. Perl used to recognize comments in some places that PCRE2 does not, for example, between the ( and ? at the start of a group. If the /x modifier is set, Perl allowed white space between ( and ? though the latest Perls give an error (for a while it was just deprecated). There may still be some cases where Perl behaves differently.
-15. Perl, when in warning mode, gives warnings for character classes such as +14. Perl, when in warning mode, gives warnings for character classes such as [A-\d] or [a-[:digit:]]. It then treats the hyphens as literals. PCRE2 has no warning features, so it gives an error in these cases because they are almost certainly user mistakes.
-16. In PCRE2, the upper/lower case character properties Lu and Ll are not +15. In PCRE2, the upper/lower case character properties Lu and Ll are not affected when case-independent matching is specified. For example, \p{Lu} always matches an upper case letter. I think Perl has changed in this respect; -in the release at the time of writing (5.24), \p{Lu} and \p{Ll} match all +in the release at the time of writing (5.32), \p{Lu} and \p{Ll} match all letters, regardless of case, when case independence is specified.
+16. From release 5.32.0, Perl locks out the use of \K in lookaround +assertions. From release 10.38 PCRE2 does the same by default. However, there +is an option for re-enabling the previous behaviour. When this option is set, +\K is acted on when it occurs in positive assertions, but is ignored in +negative assertions. +
+17. PCRE2 provides some extensions to the Perl regular expression facilities. -Perl 5.10 includes new features that are not in earlier versions of Perl, some +Perl 5.10 included new features that were not in earlier versions of Perl, some of which (such as named parentheses) were in PCRE2 for some time before. This -list is with respect to Perl 5.26: +list is with respect to Perl 5.32:
(a) Although lookbehind assertions in PCRE2 must match fixed length strings, -each alternative branch of a lookbehind assertion can match a different length -of string. Perl requires them all to have the same length. +each alternative toplevel branch of a lookbehind assertion can match a +different length of string. Perl requires them all to have the same length.
(b) From PCRE2 10.23, backreferences to groups of fixed length are supported @@ -203,7 +212,7 @@ different way and is not Perl-compatible.
(l) PCRE2 recognizes some special sequences such as (*CR) or (*NO_JIT) at -the start of a pattern that set overall options that cannot be changed within +the start of a pattern. These set overall options that cannot be changed within the pattern.
@@ -230,7 +239,7 @@ AUTHORPhilip Hazel
-University Computing Service +Retired from University Computing Service
Cambridge, England.
@@ -239,9 +248,9 @@ Cambridge, England. REVISION
-Last updated: 13 July 2019 +Last updated: 30 August 2021
-Copyright © 1997-2019 University of Cambridge. +Copyright © 1997-2021 University of Cambridge.
Return to the PCRE2 index page. diff --git a/pcre2/doc/html/pcre2convert.html b/pcre2/doc/html/pcre2convert.html index 871e563..c3d4cac 100644 --- a/pcre2/doc/html/pcre2convert.html +++ b/pcre2/doc/html/pcre2convert.html @@ -141,8 +141,8 @@ permitted to match separator characters, but the double-star (**) feature
PCRE2_CONVERT_GLOB_NO_WILD_SEPARATOR matches globs with wildcards allowed to -match separator characters. PCRE2_GLOB_NO_STARSTAR matches globs with the -double-star feature disabled. These options may be given together. +match separator characters. PCRE2_CONVERT_GLOB_NO_STARSTAR matches globs with +the double-star feature disabled. These options may be given together.
CONVERTING POSIX PATTERNS
diff --git a/pcre2/doc/html/pcre2demo.html b/pcre2/doc/html/pcre2demo.html index 08b2190..1f84373 100644 --- a/pcre2/doc/html/pcre2demo.html +++ b/pcre2/doc/html/pcre2demo.html @@ -215,8 +215,8 @@ if (rc < 0) return 1; } -/* Match succeded. Get a pointer to the output vector, where string offsets are -stored. */ +/* Match succeeded. Get a pointer to the output vector, where string offsets +are stored. */ ovector = pcre2_get_ovector_pointer(match_data); printf("Match succeeded at offset %d\n", (int)ovector[0]); @@ -234,9 +234,12 @@ pcre2_match_data_create_from_pattern() above. */ if (rc == 0) printf("ovector was not big enough for all the captured substrings\n"); -/* We must guard against patterns such as /(?=.\K)/ that use \K in an assertion -to set the start of a match later than its end. In this demonstration program, -we just detect this case and give up. */ +/* Since release 10.38 PCRE2 has locked out the use of \K in lookaround +assertions. However, there is an option to re-enable the old behaviour. If that +is set, it is possible to run patterns such as /(?=.\K)/ that use \K in an +assertion to set the start of a match later than its end. In this demonstration +program, we show how to detect this case, but it shouldn't arise because the +option is never set. */ if (ovector[0] > ovector[1]) { @@ -453,7 +456,7 @@ for (;;) return 1; } - /* Match succeded */ + /* Match succeeded */ printf("\nMatch succeeded again at offset %d\n", (int)ovector[0]); diff --git a/pcre2/doc/html/pcre2grep.html b/pcre2/doc/html/pcre2grep.html index 0b2f241..b3252d3 100644 --- a/pcre2/doc/html/pcre2grep.html +++ b/pcre2/doc/html/pcre2grep.html @@ -111,8 +111,8 @@ matching substrings, or if --only-matching, --file-offsets, or (either shown literally, or as an offset), scanning resumes immediately following the match, so that further matches on the same line can be found. If there are multiple patterns, they are all tried on the remainder of the line, -but patterns that follow the one that matched are not tried on the earlier part -of the line. +but patterns that follow the one that matched are not tried on the earlier +matched part of the line.
This behaviour means that the order in which multiple patterns are specified @@ -146,11 +146,10 @@ ignored.
BINARY FILES
By default, a file that contains a binary zero byte within the first 1024 bytes -is identified as a binary file, and is processed specially. (GNU grep -identifies binary files in this manner.) However, if the newline type is -specified as NUL, that is, the line terminator is a binary zero, the test for -a binary file is not applied. See the --binary-files option for a means -of changing the way binary files are handled. +is identified as a binary file, and is processed specially. However, if the +newline type is specified as NUL, that is, the line terminator is a binary +zero, the test for a binary file is not applied. See the --binary-files +option for a means of changing the way binary files are handled.
BINARY ZEROS IN PATTERNS
@@ -189,6 +188,12 @@ Treat binary files as text. This is equivalent to --binary-files=text.
+--allow-lookaround-bsk +PCRE2 now forbids the use of \K in lookarounds by default, in line with Perl. +This option causes pcre2grep to set the PCRE2_EXTRA_ALLOW_LOOKAROUND_BSK +option, which enables this somewhat dangerous usage. +
+-B number, --before-context=number Output up to number lines of context before each matching line. Fewer lines are output if the previous match or the start of the file is within @@ -443,8 +448,8 @@ Ignore upper/lower case distinctions during comparisons.
--include=pattern If any --include patterns are specified, the only files that are -processed are those that match one of the patterns (and do not match an ---exclude pattern). This option does not affect directories, but it +processed are those whose names match one of the patterns and do not match an +--exclude pattern. This option does not affect directories, but it applies to all files, whether listed on the command line, obtained from --file-list, or by scanning a directory. The pattern is a PCRE2 regular expression, and is matched against the final component of the file name, not @@ -463,8 +468,8 @@ may be given any number of times; all the files are read.
--include-dir=pattern If any --include-dir patterns are specified, the only directories that -are processed are those that match one of the patterns (and do not match an ---exclude-dir pattern). This applies to all directories, whether listed +are processed are those whose names match one of the patterns and do not match +an --exclude-dir pattern. This applies to all directories, whether listed on the command line, obtained from --file-list, or by scanning a parent directory. The pattern is a PCRE2 regular expression, and is matched against the final component of the directory name, not the entire path. The -F, @@ -487,8 +492,9 @@ a separate line. Searching normally stops as soon as a matching line is found in a file. However, if the -c (count) option is also used, matching continues in order to obtain the correct count, and those files that have at least one match are listed along with their counts. Using this option with --c is a way of suppressing the listing of files with no matches. This -opeion overrides any previous -H, -h, or -L options. +-c is a way of suppressing the listing of files with no matches that +occurs with -c on its own. This option overrides any previous -H, +-h, or -L options.
--label=name @@ -501,8 +507,8 @@ short form for this option. When this option is given, non-compressed input is read and processed line by line, and the output is flushed after each write. By default, input is read in large chunks, unless pcre2grep can determine that it is reading from a -terminal (which is currently possible only in Unix-like environments or -Windows). Output to terminal is normally automatically flushed by the operating +terminal, which is currently possible only in Unix-like environments or +Windows. Output to terminal is normally automatically flushed by the operating system. This option can be useful when the input or output is attached to a pipe and you do not want pcre2grep to buffer up large amounts of data. However, its use will affect performance, and the -M (multiline) option @@ -528,6 +534,49 @@ locale is specified, the PCRE2 library's default (usually the "C" locale) is used. There is no short form for this option.
+-M, --multiline +Allow patterns to match more than one line. When this option is set, the PCRE2 +library is called in "multiline" mode. This allows a matched string to extend +past the end of a line and continue on one or more subsequent lines. Patterns +used with -M may usefully contain literal newline characters and internal +occurrences of ^ and $ characters. The output for a successful match may +consist of more than one line. The first line is the line in which the match +started, and the last line is the line in which the match ended. If the matched +string ends with a newline sequence, the output ends at the end of that line. +If -v is set, none of the lines in a multi-line match are output. Once a +match has been handled, scanning restarts at the beginning of the line after +the one in which the match ended. +
+
+The newline sequence that separates multiple lines must be matched as part of +the pattern. For example, to find the phrase "regular expression" in a file +where "regular" might be at the end of a line and "expression" at the start of +the next line, you could use this command: ++ pcre2grep -M 'regular\s+expression' <file> ++The \s escape sequence matches any white space character, including newlines, +and is followed by + so as to match trailing white space on the first line as +well as possibly handling a two-character newline sequence. +
+
+There is a limit to the number of lines that can be matched, imposed by the way +that pcre2grep buffers the input file as it scans it. With a sufficiently +large processing buffer, this should not be a problem, but the -M option +does not work when input is read line by line (see --line-buffered.) + ++-m number, --max-count=number +Stop processing after finding number matching lines, or non-matching +lines if -v is also set. Any trailing context lines are output after the +final match. In multiline mode, each multiline match counts as just one line +for this purpose. If this limit is reached when reading the standard input from +a regular file, the file is left positioned just after the last matching line. +If -c is also set, the count that is output is never greater than +number. This option has no effect if used with -L, -l, or +-q, or when just checking for a match in a binary file. +
+--match-limit=number Processing some regular expression patterns may take a very long time to search for all possible matching strings. Others may require a very large amount of @@ -568,38 +617,6 @@ set by --buffer-size. The maximum buffer size is silently forced to be no smaller than the starting buffer size.
--M, --multiline -Allow patterns to match more than one line. When this option is set, the PCRE2 -library is called in "multiline" mode. This allows a matched string to extend -past the end of a line and continue on one or more subsequent lines. Patterns -used with -M may usefully contain literal newline characters and internal -occurrences of ^ and $ characters. The output for a successful match may -consist of more than one line. The first line is the line in which the match -started, and the last line is the line in which the match ended. If the matched -string ends with a newline sequence, the output ends at the end of that line. -If -v is set, none of the lines in a multi-line match are output. Once a -match has been handled, scanning restarts at the beginning of the line after -the one in which the match ended. -
-
-The newline sequence that separates multiple lines must be matched as part of -the pattern. For example, to find the phrase "regular expression" in a file -where "regular" might be at the end of a line and "expression" at the start of -the next line, you could use this command: -- pcre2grep -M 'regular\s+expression' <file> --The \s escape sequence matches any white space character, including newlines, -and is followed by + so as to match trailing white space on the first line as -well as possibly handling a two-character newline sequence. -
-
-There is a limit to the number of lines that can be matched, imposed by the way -that pcre2grep buffers the input file as it scans it. With a sufficiently -large processing buffer, this should not be a problem, but the -M option -does not work when input is read line by line (see --line-buffered.) - --N newline-type, --newline=newline-type Six different conventions for indicating the ends of lines in scanned files are supported. For example: @@ -648,31 +665,41 @@ It should never be needed in normal use.
-O text, --output=text -When there is a match, instead of outputting the whole line that matched, -output just the given text, followed by an operating-system standard newline. -The --newline option has no effect on this option, which is mutually -exclusive with --only-matching, --file-offsets, and ---line-offsets. Escape sequences starting with a dollar character may be -used to insert the contents of the matched part of the line and/or captured -substrings into the text. +When there is a match, instead of outputting the line that matched, output just +the text specified in this option, followed by an operating-system standard +newline. In this mode, no context is shown. That is, the -A, -B, +and -C options are ignored. The --newline option has no effect on +this option, which is mutually exclusive with --only-matching, +--file-offsets, and --line-offsets. However, like +--only-matching, if there is more than one match in a line, each of them +causes a line of output. +
+
+Escape sequences starting with a dollar character may be used to insert the +contents of the matched part of the line and/or captured substrings into the +text.
-$<digits> or ${<digits>} is replaced by the captured -substring of the given decimal number; zero substitutes the whole match. If -the number is greater than the number of capturing substrings, or if the -capture is unset, the replacement is empty. +$<digits> or ${<digits>} is replaced by the captured substring of the given +decimal number; zero substitutes the whole match. If the number is greater than +the number of capturing substrings, or if the capture is unset, the replacement +is empty.
$a is replaced by bell; $b by backspace; $e by escape; $f by form feed; $n by newline; $r by carriage return; $t by tab; $v by vertical tab.
-$o<digits> is replaced by the character represented by the given octal -number; up to three digits are processed. +$o<digits> or $o{<digits>} is replaced by the character whose code point is the +given octal number. In the first form, up to three octal digits are processed. +When more digits are needed in Unicode mode to specify a wide character, the +second form must be used.
-$x<digits> is replaced by the character represented by the given hexadecimal -number; up to two digits are processed. +$x<digits> or $x{<digits>} is replaced by the character represented by the +given hexadecimal number. In the first form, up to two hexadecimal digits are +processed. When more digits are needed in Unicode mode to specify a wide +character, the second form must be used.
Any other character is substituted by itself. In particular, $$ is replaced by @@ -741,7 +768,8 @@ option to "recurse".--recursion-limit=number -See --match-limit above. +This is an obsolete synonym for --depth-limit. See --match-limit +above for details.
-s, --no-messages @@ -765,15 +793,18 @@ total would always be zero. -u, --utf Operate in UTF-8 mode. This option is available only if PCRE2 has been compiled with UTF-8 support. All patterns (including those for any --exclude and ---include options) and all subject lines that are scanned must be valid -strings of UTF-8 characters. +--include options) and all lines that are scanned must be valid strings +of UTF-8 characters. If an invalid UTF-8 string is encountered, an error +occurs.
-U, --utf-allow-invalid As --utf, but in addition subject lines may contain invalid UTF-8 code -unit sequences. These can never form part of any pattern match. This facility -allows valid UTF-8 strings to be sought in executable or other binary files. -For more details about matching in non-valid UTF-8 strings, see the +unit sequences. These can never form part of any pattern match. Patterns +themselves, however, must still be valid UTF-8 strings. This facility allows +valid UTF-8 strings to be sought within arbitrary byte sequences in executable +or other binary files. For more details about matching in non-valid UTF-8 +strings, see the pcre2unicode(3) documentation.
@@ -786,7 +817,9 @@ ignored.-v, --invert-match Invert the sense of the match, so that lines which do not match any of -the patterns are the ones that are found. +the patterns are the ones that are found. When this option is set, options such +as --only-matching and --output, which specify parts of a match +that are to be output, are ignored.
-w, --word-regex, --word-regexp @@ -909,12 +942,36 @@ documentation for details). Numbered callouts are ignored by pcre2grep; only callouts with string arguments are useful.
+Echoing a specific string +
++Starting the callout string with a pipe character invokes an echoing facility +that avoids calling an external program or script. This facility is always +available, provided that callouts were not completely disabled when +pcre2grep was built. The rest of the callout string is processed as a +zero-terminated string, which means it should not contain any internal binary +zeros. It is written to the output, having first been passed through the same +escape processing as text from the --output (-O) option (see +above). However, $0 cannot be used to insert a matched substring because the +match is still in progress. Instead, the single character '0' is inserted. Any +syntax errors in the string (for example, a dollar not followed by another +character) causes the callout to be ignored. No terminator is added to the +output string, so if you want a newline, you must include it explicitly using +the escape $n. For example: +
+ pcre2grep '(.)(..(.))(?C"|[$1] [$2] [$3]$n")' <some file> ++Matching continues normally after the string is output. If you want to see only +the callout output but not any output from an actual match, you should end the +pattern with (*FAIL). + +
Calling external programs or scripts
This facility can be independently disabled when pcre2grep is built. It is supported for Windows, where a call to _spawnvp() is used, for VMS, -where lib$spawn() is used, and for any other Unix-like environment where +where lib$spawn() is used, and for any Unix-like environment where fork() and execv() are available.
@@ -926,14 +983,11 @@ arguments: executable_name|arg1|arg2|...
-Any other character is substituted by itself. In particular, $$ is replaced by -a single dollar and $| is replaced by a pipe character. Here is an example: +started by a dollar character. These are the same as for the --output +(-O) option documented above, except that $0 cannot insert the matched +string because the match is still in progress. Instead, the character '0' +is inserted. If you need a literal dollar or pipe character in any +substring, use $$ or $| respectively. Here is an example:
echo -e "abcde\n12345" | pcre2grep \ '(?x)(.)(..(.)) @@ -946,28 +1000,14 @@ a single dollar and $| is replaced by a pipe character. Here is an example: Arg1: [1] [234] [4] Arg2: |1| () 12345-The parameters for the system call that is used to run the -program or script are zero-terminated strings. This means that binary zero -characters in the callout argument will cause premature termination of their -substrings, and therefore should not be present. Any syntax errors in the -string (for example, a dollar not followed by another character) cause the -callout to be ignored. If running the program fails for any reason (including -the non-existence of the executable), a local matching failure occurs and the -matcher backtracks in the normal way. - -
-This facility is always available, provided that callouts were not completely -disabled when pcre2grep was built. If the callout string starts with a -pipe (vertical bar) character, the rest of the string is written to the output, -having been passed through the same escape processing as text from the --output -option. This provides a simple echoing facility that avoids calling an external -program or script. No terminator is added to the string, so if you want a -newline, you must include it explicitly. Matching continues normally after the -string is output. If you want to see only the callout output but not any output -from an actual match, you should end the relevant pattern with (*FAIL). +The parameters for the system call that is used to run the program or script +are zero-terminated strings. This means that binary zero characters in the +callout argument will cause premature termination of their substrings, and +therefore should not be present. Any syntax errors in the string (for example, +a dollar not followed by another character) causes the callout to be ignored. +If running the program fails for any reason (including the non-existence of the +executable), a local matching failure occurs and the matcher backtracks in the +normal way.
@@ -999,22 +1039,23 @@ because VMS does not distinguish between exit(0) and exit(1).
-pcre2pattern(3), pcre2syntax(3), pcre2callout(3). +pcre2pattern(3), pcre2syntax(3), pcre2callout(3), +pcre2unicode(3).
Philip Hazel
-University Computing Service
+Retired from University Computing Service
Cambridge, England.
-Last updated: 25 January 2020
+Last updated: 31 August 2021
-Copyright © 1997-2020 University of Cambridge.
+Copyright © 1997-2021 University of Cambridge.
Return to the PCRE2 index page. diff --git a/pcre2/doc/html/pcre2jit.html b/pcre2/doc/html/pcre2jit.html index 423dfd8..e73a229 100644 --- a/pcre2/doc/html/pcre2jit.html +++ b/pcre2/doc/html/pcre2jit.html @@ -54,6 +54,7 @@ platforms:
ARM 32-bit (v5, v7, and Thumb2) ARM 64-bit + IBM s390x 64 bit Intel x86 32-bit and 64-bit MIPS 32-bit and 64-bit Power PC 32-bit and 64-bit @@ -286,7 +287,7 @@ inefficient solution, and not recommended. This is a suggestion for how a multithreaded program that needs to set up non-default JIT stacks might operate:-The first part of the pattern is a DEFINE group inside which a another group +The first part of the pattern is a DEFINE group inside which another group named "byte" is defined. This matches an individual component of an IPv4 address (a number less than 256). When matching takes place, this part of the pattern is skipped because DEFINE acts like a false condition. The rest of the @@ -3593,7 +3614,7 @@ successful match if there is a later mismatch. Consider: If the subject is "aaaac...", after the first match attempt fails (starting at the first character in the string), the starting point skips on to start the -next attempt at "c". Note that a possessive quantifer does not have the same +next attempt at "c". Note that a possessive quantifier does not have the same effect as this example; although it would suppress backtracking during the first match attempt, the second attempt would start at the second character instead of skipping on to "c". @@ -3831,16 +3852,16 @@ there is a backtrack at the outer level.- During thread initalization + During thread initialization thread_local_var = pcre2_jit_stack_create(...) During thread exit diff --git a/pcre2/doc/html/pcre2matching.html b/pcre2/doc/html/pcre2matching.html index 4b71c8f..ed92caf 100644 --- a/pcre2/doc/html/pcre2matching.html +++ b/pcre2/doc/html/pcre2matching.html @@ -78,8 +78,9 @@ tried is controlled by the greedy or ungreedy nature of the quantifier. If a leaf node is reached, a matching string has been found, and at that point the algorithm stops. Thus, if there is more than one possible match, this algorithm returns the first one that it finds. Whether this is the shortest, -the longest, or some intermediate length depends on the way the greedy and -ungreedy repetition quantifiers are specified in the pattern. +the longest, or some intermediate length depends on the way the alternations +and the greedy or ungreedy repetition quantifiers are specified in the +pattern.+If a pattern is compiled with the PCRE2_EXTENDED option, most white space in +the pattern, other than in a character class, and characters between a # +outside a character class and the next newline, inclusive, are ignored. An +escaping backslash can be used to include a white space or a # character as +part of the pattern. If the PCRE2_EXTENDED_MORE option is set, the same +applies, but in addition unescaped space and horizontal tab characters are +ignored inside a character class. Note: only these two characters are ignored, +not the full set of pattern white space characters that are ignored outside a +character class. Option settings can be changed within a pattern; see the +section entitled +"Internal Option Setting" +below. + +Because it ends up with a single path through the tree, it is relatively @@ -109,11 +110,17 @@ no more unterminated paths. At this point, terminated paths represent the different matching possibilities (if there are none, the match has failed). Thus, if there is more than one possible match, this algorithm finds all of them, and in particular, it finds the longest. The matches are returned in -decreasing order of length. There is an option to stop the algorithm after the -first match (which is necessarily the shortest) is found. +the output vector in decreasing order of length. There is an option to stop the +algorithm after the first match (which is necessarily the shortest) is found.
-Note that all the matches that are found start at the same point in the +Note that the size of vector needed to contain all the results depends on the +number of simultaneous matches, not on the number of parentheses in the +pattern. Using pcre2_match_data_create_from_pattern() to create the match +data block is therefore not advisable when doing DFA matching. +
++Note also that all the matches that are found start at the same point in the subject. If the pattern
cat(er(pillar)?)? @@ -194,21 +201,14 @@ supported by pcre2_dfa_match().matches a portion of a subject string that is identical to itself. When -caseless matching is specified (the PCRE2_CASELESS option), letters are matched -independently of case. +caseless matching is specified (the PCRE2_CASELESS option or (?i) within the +pattern), letters are matched independently of case. Note that there are two +ASCII characters, K and S, that, in addition to their lower case ASCII +equivalents, are case-equivalent with Unicode U+212A (Kelvin sign) and U+017F +(long S) respectively when either PCRE2_UTF or PCRE2_UCP is set.
ADVANTAGES OF THE ALTERNATIVE ALGORITHM
-Using the alternative matching algorithm provides the following advantages: -
--1. All possible matches (at a single point in the subject) are automatically -found, and in particular, the longest match is found. To find more than one -match using the standard algorithm, you have to do kludgy things with -callouts. +The main advantage of the alternative algorithm is that all possible matches +(at a single point in the subject) are automatically found, and in particular, +the longest match is found. To find more than one match at the same point using +the standard algorithm, you have to do kludgy things with callouts.
-2. Because the alternative algorithm scans the subject string just once, and -never needs to backtrack (except for lookbehinds), it is possible to pass very -long subject strings to the matching function in several pieces, checking for -partial matching each time. Although it is also possible to do multi-segment -matching using the standard algorithm, by retaining partially matched -substrings, it is more complicated. The +Partial matching is possible with this algorithm, though it has some +limitations. The pcre2partial documentation gives details of partial matching and discusses multi-segment matching. @@ -230,20 +230,23 @@ invalid UTF string are not supported. 3. Although atomic groups are supported, their use does not provide the performance advantage that it does for the standard algorithm.
++4. JIT optimization is not supported. +
AUTHOR
Philip Hazel
-University Computing Service +Retired from University Computing Service
Cambridge, England.
REVISION
-Last updated: 23 May 2019 +Last updated: 28 August 2021
-Copyright © 1997-2019 University of Cambridge. +Copyright © 1997-2021 University of Cambridge.
Return to the PCRE2 index page. diff --git a/pcre2/doc/html/pcre2pattern.html b/pcre2/doc/html/pcre2pattern.html index ec2e8c9..9c2d66c 100644 --- a/pcre2/doc/html/pcre2pattern.html +++ b/pcre2/doc/html/pcre2pattern.html @@ -289,8 +289,11 @@ corresponding characters in the subject. As a trivial example, the pattern The quick brown fox
The power of regular expressions comes from the ability to include wild cards, @@ -326,6 +329,20 @@ a character class the only metacharacters are: [ POSIX character class (if followed by POSIX syntax) ] terminates the character class
The following sections describe the use of each of the metacharacters.
BACKSLASH
@@ -343,16 +360,9 @@ precede a non-alphanumeric with backslash to specify that it stands for itself. In particular, if you want to match a backslash, you write \\.-In a UTF mode, only ASCII digits and letters have any special meaning after a -backslash. All other characters (in particular, those whose code points are -greater than 127) are treated as literals. -
--If a pattern is compiled with the PCRE2_EXTENDED option, most white space in -the pattern (other than in a character class), and characters between a # -outside a character class and the next newline, inclusive, are ignored. An -escaping backslash can be used to include a white space or # character as part -of the pattern. +Only ASCII digits and letters have any special meaning after a backslash. All +other characters (in particular, those whose code points are greater than 127) +are treated as literals.
If you want to treat all characters in a sequence as literals, you can do so by @@ -735,7 +745,7 @@ Unicode support is not needed for these characters to be recognized.
It is possible to restrict \R to match only CR, LF, or CRLF (instead of the complete set of Unicode line endings) by setting the option PCRE2_BSR_ANYCRLF -at compile time. (BSR is an abbrevation for "backslash R".) This can be made +at compile time. (BSR is an abbreviation for "backslash R".) This can be made the default when PCRE2 is built; if this is the case, the other behaviour can be requested via the PCRE2_BSR_UNICODE option. It is also possible to specify these settings by starting a pattern string with one of the following @@ -824,6 +834,7 @@ Common, Coptic, Cuneiform, Cypriot, +Cypro_Minoan, Cyrillic, Deseret, Devanagari, @@ -907,6 +918,7 @@ Old_Persian, Old_Sogdian, Old_South_Arabian, Old_Turkic, +Old_Uyghur, Oriya, Osage, Osmanya, @@ -938,6 +950,7 @@ Tai_Tham, Tai_Viet, Takri, Tamil, +Tangsa, Tangut, Telugu, Thaana, @@ -945,9 +958,11 @@ Thai, Tibetan, Tifinagh, Tirhuta, +Toto, Ugaritic, Unknown, Vai, +Vithkuqi, Wancho, Warang_Citi, Yezidi, @@ -1080,7 +1095,7 @@ additional characters according to the following rules for ending a cluster: 3. Do not break Hangul (a Korean script) syllable sequences. Hangul characters are of five types: L, V, T, LV, and LVT. An L character may be followed by an L, V, LV, or LVT character; an LV or V character may be followed by a V or T -character; an LVT or T character may be follwed only by a T character. +character; an LVT or T character may be followed only by a T character.
4. Do not end before extending characters or spacing marks or the "zero-width @@ -1165,8 +1180,11 @@ For example, when the pattern matches "foobar", the first substring is still set to "foo".
-Perl documents that the use of \K within assertions is "not well defined". In -PCRE2, \K is acted upon when it occurs inside positive assertions, but is +From version 5.32.0 Perl forbids the use of \K in lookaround assertions. From +release 10.38 PCRE2 also forbids this by default. However, the +PCRE2_EXTRA_ALLOW_LOOKAROUND_BSK option can be used when calling +pcre2_compile() to re-enable the previous behaviour. When this option is +set, \K is acted upon when it occurs inside positive assertions, but is ignored in negative assertions. Note that when a pattern such as (?=ab\K) matches, the reported start of the match can be greater than the end of the match. Using \K in a lookbehind assertion at the start of a pattern can also @@ -1443,7 +1461,10 @@ Characters in a class may be specified by their code points using \o, \x, or \N{U+hh..} in the usual way. When caseless matching is set, any letters in a class represent both their upper case and lower case versions, so for example, a caseless [aeiou] matches "A" as well as "a", and a caseless [^aeiou] does not -match "A", whereas a caseful version would. +match "A", whereas a caseful version would. Note that there are two ASCII +characters, K and S, that, in addition to their lower case ASCII equivalents, +are case-equivalent with Unicode U+212A (Kelvin sign) and U+017F (long S) +respectively when either PCRE2_UTF or PCRE2_UCP is set.
Characters that might indicate line breaks are never treated in any special way @@ -2883,7 +2904,7 @@ breaks): (?(DEFINE) (?<byte> 2[0-4]\d | 25[0-5] | 1\d\d | [1-9]?\d) ) \b (?&byte) (\.(?&byte)){3} \b
Philip Hazel
-University Computing Service
+Retired from University Computing Service
Cambridge, England.
-Last updated: 24 February 2020
+Last updated: 30 August 2021
-Copyright © 1997-2020 University of Cambridge.
+Copyright © 1997-2021 University of Cambridge.
Return to the PCRE2 index page. diff --git a/pcre2/doc/html/pcre2posix.html b/pcre2/doc/html/pcre2posix.html index 20a2009..0ad6f9e 100644 --- a/pcre2/doc/html/pcre2posix.html +++ b/pcre2/doc/html/pcre2posix.html @@ -68,11 +68,14 @@ application. Because the POSIX functions call the native ones, it is also necessary to add -lpcre2-8.
-Although they are not defined as protypes in pcre2posix.h, the library -does contain functions with the POSIX names regcomp() etc. These simply -pass their arguments to the PCRE2 functions. These functions are provided for -backwards compatibility with earlier versions of PCRE2, so that existing -programs do not have to be recompiled. +Although they were not defined as protypes in pcre2posix.h, releases +10.33 to 10.36 of the library contained functions with the POSIX names +regcomp() etc. These simply passed their arguments to the PCRE2 +functions. These functions were provided for backwards compatibility with +earlier versions of PCRE2, which had only POSIX names. However, this has proved +troublesome in situations where a program links with several libraries, some of +which use PCRE2's POSIX interface while others use the real POSIX functions. +For this reason, the POSIX names have been removed since release 10.37.
Calling the header file pcre2posix.h avoids any conflict with other POSIX @@ -344,9 +347,9 @@ Cambridge, England.
-Last updated: 30 January 2019
+Last updated: 26 April 2021
-Copyright © 1997-2019 University of Cambridge.
+Copyright © 1997-2021 University of Cambridge.
Return to the PCRE2 index page. diff --git a/pcre2/doc/html/pcre2syntax.html b/pcre2/doc/html/pcre2syntax.html index 7383104..735eb69 100644 --- a/pcre2/doc/html/pcre2syntax.html +++ b/pcre2/doc/html/pcre2syntax.html @@ -228,6 +228,7 @@ Common, Coptic, Cuneiform, Cypriot, +Cypro_Minoan, Cyrillic, Deseret, Devanagari, @@ -311,6 +312,7 @@ Old_Persian, Old_Sogdian, Old_South_Arabian, Old_Turkic, +Old_Uyghur, Oriya, Osage, Osmanya, @@ -342,6 +344,7 @@ Tai_Tham, Tai_Viet, Takri, Tamil, +Tangsa, Tangut, Telugu, Thaana, @@ -349,8 +352,10 @@ Thai, Tibetan, Tifinagh, Tirhuta, +Toto, Ugaritic, Vai, +Vithkuqi, Wancho, Warang_Citi, Yezidi, @@ -429,6 +434,9 @@ but some of them use Unicode properties if PCRE2_UCP is set. You can use
\K set reported start of match+From release 10.38 \K is not permitted by default in lookaround assertions, +for compatibility with Perl. However, if the PCRE2_EXTRA_ALLOW_LOOKAROUND_BSK +option is set, the previous behaviour is re-enabled. When this option is set, \K is honoured in positive assertions, but ignored in negative ones.
Philip Hazel
-University Computing Service
+Retired from University Computing Service
Cambridge, England.
-Last updated: 28 December 2019
+Last updated: 30 August 2021
-Copyright © 1997-2019 University of Cambridge.
+Copyright © 1997-2021 University of Cambridge.
Return to the PCRE2 index page. diff --git a/pcre2/doc/html/pcre2test.html b/pcre2/doc/html/pcre2test.html index 920b265..3ee51cd 100644 --- a/pcre2/doc/html/pcre2test.html +++ b/pcre2/doc/html/pcre2test.html @@ -59,12 +59,7 @@ patterns, and the subject lines specify PCRE2 function options, control how the subject is processed, and what output is produced.
-As the original fairly simple PCRE library evolved, it acquired many different
-features, and as a result, the original pcretest program ended up with a
-lot of options in a messy, arcane syntax for testing all the features. The
-move to the new PCRE2 API provided an opportunity to re-implement the test
-program as pcre2test, with a cleaner modifier syntax. Nevertheless, there
-are still many obscure modifiers, some of which are specifically designed for
+There are many obscure modifiers, some of which are specifically designed for
use in conjunction with the test script and data files that are distributed as
part of PCRE2. All the modifiers are documented here, some without much
justification, but many of them are unlikely to be of use except when testing
@@ -89,10 +84,10 @@ names used in the libraries have a suffix _8, _16, or _32, as appropriate.
INPUT ENCODING
Input to pcre2test is processed line by line, either by calling the C -library's fgets() function, or via the libreadline library. In some -Windows environments character 26 (hex 1A) causes an immediate end of file, and -no further data is read, so this character should be avoided unless you really -want that action. +library's fgets() function, or via the libreadline or libedit +library. In some Windows environments character 26 (hex 1A) causes an immediate +end of file, and no further data is read, so this character should be avoided +unless you really want that action.
The input is processed using using C's string functions, so must not @@ -323,7 +318,7 @@ test data, command lines that begin with # may appear. This file format, with some restrictions, can also be processed by the perltest.sh script that is distributed with PCRE2 as a means of checking that the behaviour of PCRE2 and Perl is the same. For a specification of perltest.sh, see the -comments near its beginning. +comments near its beginning. See also the #perltest command below.
When the input is a terminal, pcre2test prompts for each line of input, @@ -420,14 +415,20 @@ patterns. Modifiers on a pattern can change these settings.
#perltest-The appearance of this line causes all subsequent modifier settings to be -checked for compatibility with the perltest.sh script, which is used to -confirm that Perl gives the same results as PCRE2. Also, apart from comment -lines, #pattern commands, and #subject commands that set or unset "mark", no -command lines are permitted, because they and many of the modifiers are -specific to pcre2test, and should not be used in test files that are also -processed by perltest.sh. The #perltest command helps detect tests -that are accidentally put in the wrong file. +This line is used in test files that can also be processed by perltest.sh +to confirm that Perl gives the same results as PCRE2. Subsequent tests are +checked for the use of pcre2test features that are incompatible with the +perltest.sh script. + +
+Patterns must use '/' as their delimiter, and only certain modifiers are +supported. Comment lines, #pattern commands, and #subject commands that set or +unset "mark" are recognized and acted on. The #perltest, #forbid_utf, and +#newline_default commands, which are needed in the relevant pcre2test files, +are silently ignored. All other command lines are ignored, but give a warning +message. The #perltest command helps detect tests that are accidentally +put in the wrong file or use the wrong delimiter. For more details of the +perltest.sh script see the comments it contains.
#pop [<modifiers>] #popcopy [<modifiers>] @@ -480,15 +481,17 @@ excluding pattern meta-characters):This is interpreted as the pattern's delimiter. A regular expression may be continued over several input lines, in which case the newline characters are -included within it. It is possible to include the delimiter within the pattern -by escaping it with a backslash, for example +included within it. It is possible to include the delimiter as a literal within +the pattern by escaping it with a backslash, for example
/abc\/def/If you do this, the escape and the delimiter form part of the pattern, but -since the delimiters are all non-alphanumeric, this does not affect its -interpretation. If the terminating delimiter is immediately followed by a -backslash, for example, +since the delimiters are all non-alphanumeric, the inclusion of the backslash +does not affect the pattern's interpretation. Note, however, that this trick +does not work within \Q...\E literal bracketing because the backslash will +itself be interpreted as a literal. If the terminating delimiter is immediately +followed by a backslash, for example,
/abc/\@@ -506,11 +509,11 @@ A pattern can be followed by a modifier list (details below).
-Before each subject line is passed to pcre2_match() or -pcre2_dfa_match(), leading and trailing white space is removed, and the -line is scanned for backslash escapes, unless the subject_literal -modifier was set for the pattern. The following provide a means of encoding -non-printing characters in a visible way: +Before each subject line is passed to pcre2_match(), +pcre2_dfa_match(), or pcre2_jit_match(), leading and trailing white +space is removed, and the line is scanned for backslash escapes, unless the +subject_literal modifier was set for the pattern. The following provide a +means of encoding non-printing characters in a visible way:
\a alarm (BEL, \x07) \b backspace (\x08) @@ -607,6 +610,7 @@ way pcre2_compile() behaves. See for a description of the effects of these options.allow_empty_class set PCRE2_ALLOW_EMPTY_CLASS + allow_lookaround_bsk set PCRE2_EXTRA_ALLOW_LOOKAROUND_BSK allow_surrogate_escapes set PCRE2_EXTRA_ALLOW_SURROGATE_ESCAPES alt_bsux set PCRE2_ALT_BSUX alt_circumflex set PCRE2_ALT_CIRCUMFLEX @@ -1207,7 +1211,7 @@ Setting match controls The following modifiers affect the matching process or request additional information. Some of them may also be specified on a pattern line (see above), in which case they apply to every subject line that is matched against that -pattern. +pattern, but can be overridden by modifiers on the subject.aftertext show text after match allaftertext show text after captures @@ -1415,6 +1419,11 @@ replacement strings cannot contain commas, because a comma signifies the end of a modifier. This is not thought to be an issue in a test program.+Specifying a completely empty replacement string disables this modifier. +However, it is possible to specify an empty replacement by providing a buffer +length, as described below, for an otherwise empty replacement. +
+Unlike subject strings, pcre2test does not process replacement strings for escape sequences. In UTF mode, a replacement string is checked to see if it is a valid UTF-8 string. If so, it is correctly converted to a UTF string of @@ -2106,16 +2115,16 @@ on the stack.
Philip Hazel
-University Computing Service +Retired from University Computing Service
Cambridge, England.
REVISION
-Last updated: 20 March 2020 +Last updated: 30 August 2021
-Copyright © 1997-2020 University of Cambridge. +Copyright © 1997-2021 University of Cambridge.
Return to the PCRE2 index page. diff --git a/pcre2/doc/pcre2.3 b/pcre2/doc/pcre2.3 index 75450ec..fa91450 100644 --- a/pcre2/doc/pcre2.3 +++ b/pcre2/doc/pcre2.3 @@ -1,4 +1,4 @@ -.TH PCRE2 3 "17 September 2018" "PCRE2 10.33" +.TH PCRE2 3 "27 August 2021" "PCRE2 10.38" .SH NAME PCRE2 - Perl-compatible regular expressions (revised API) .SH INTRODUCTION @@ -11,7 +11,8 @@ nearly two decades, the limitations of the original API were making development increasingly difficult. The new API is more extensible, and it was simplified by abolishing the separate "study" optimizing function; in PCRE2, patterns are automatically optimized where possible. Since forking from PCRE1, the code has -been extensively refactored and new features introduced. +been extensively refactored and new features introduced. The old library is now +obsolete and is no longer maintained. .P As well as Perl-style regular expression patterns, some features that appeared in Python and the original PCRE before they appeared in Perl are available @@ -19,8 +20,13 @@ using the Python syntax. There is also some support for one or two .NET and Oniguruma syntax items, and there are options for requesting some minor changes that give better ECMAScript (aka JavaScript) compatibility. .P -The source code for PCRE2 can be compiled to support 8-bit, 16-bit, or 32-bit -code units, which means that up to three separate libraries may be installed. +The source code for PCRE2 can be compiled to support strings of 8-bit, 16-bit, +or 32-bit code units, which means that up to three separate libraries may be +installed, one for each code unit size. The size of code unit is not related to +the bit size of the underlying hardware. In a 64-bit environment that also +supports 32-bit applications, versions of PCRE2 that are compiled in both +64-bit and 32-bit modes may be needed. +.P The original work to extend PCRE to 16-bit and 32-bit code units was done by Zoltan Herczeg and Christian Persch, respectively. In all three cases, strings can be interpreted either as one character per code unit, or as UTF-encoded @@ -185,18 +191,18 @@ function, listing its arguments and results. .sp .nf Philip Hazel -University Computing Service +Retired from University Computing Service Cambridge, England. .fi .P Putting an actual email address here is a spam magnet. If you want to email me, -use my two initials, followed by the two digits 10, at the domain cam.ac.uk. +use my two names separated by a dot at gmail.com. . . .SH REVISION .rs .sp .nf -Last updated: 17 September 2018 -Copyright (c) 1997-2018 University of Cambridge. +Last updated: 27 August 2021 +Copyright (c) 1997-2021 University of Cambridge. .fi diff --git a/pcre2/doc/pcre2.txt b/pcre2/doc/pcre2.txt index 4651bba..dde66a1 100644 --- a/pcre2/doc/pcre2.txt +++ b/pcre2/doc/pcre2.txt @@ -25,25 +25,31 @@ INTRODUCTION API is more extensible, and it was simplified by abolishing the sepa- rate "study" optimizing function; in PCRE2, patterns are automatically optimized where possible. Since forking from PCRE1, the code has been - extensively refactored and new features introduced. - - As well as Perl-style regular expression patterns, some features that - appeared in Python and the original PCRE before they appeared in Perl - are available using the Python syntax. There is also some support for - one or two .NET and Oniguruma syntax items, and there are options for - requesting some minor changes that give better ECMAScript (aka Java- + extensively refactored and new features introduced. The old library is + now obsolete and is no longer maintained. + + As well as Perl-style regular expression patterns, some features that + appeared in Python and the original PCRE before they appeared in Perl + are available using the Python syntax. There is also some support for + one or two .NET and Oniguruma syntax items, and there are options for + requesting some minor changes that give better ECMAScript (aka Java- Script) compatibility. - The source code for PCRE2 can be compiled to support 8-bit, 16-bit, or - 32-bit code units, which means that up to three separate libraries may - be installed. The original work to extend PCRE to 16-bit and 32-bit - code units was done by Zoltan Herczeg and Christian Persch, respec- - tively. In all three cases, strings can be interpreted either as one - character per code unit, or as UTF-encoded Unicode, with support for - Unicode general category properties. Unicode support is optional at - build time (but is the default). However, processing strings as UTF - code units must be enabled explicitly at run time. The version of Uni- - code in use can be discovered by running + The source code for PCRE2 can be compiled to support strings of 8-bit, + 16-bit, or 32-bit code units, which means that up to three separate li- + braries may be installed, one for each code unit size. The size of code + unit is not related to the bit size of the underlying hardware. In a + 64-bit environment that also supports 32-bit applications, versions of + PCRE2 that are compiled in both 64-bit and 32-bit modes may be needed. + + The original work to extend PCRE to 16-bit and 32-bit code units was + done by Zoltan Herczeg and Christian Persch, respectively. In all three + cases, strings can be interpreted either as one character per code + unit, or as UTF-encoded Unicode, with support for Unicode general cate- + gory properties. Unicode support is optional at build time (but is the + default). However, processing strings as UTF code units must be enabled + explicitly at run time. The version of Unicode in use can be discovered + by running pcre2test -C @@ -167,18 +173,17 @@ USER DOCUMENTATION AUTHOR Philip Hazel - University Computing Service + Retired from University Computing Service Cambridge, England. Putting an actual email address here is a spam magnet. If you want to - email me, use my two initials, followed by the two digits 10, at the - domain cam.ac.uk. + email me, use my two names separated by a dot at gmail.com. REVISION - Last updated: 17 September 2018 - Copyright (c) 1997-2018 University of Cambridge. + Last updated: 27 August 2021 + Copyright (c) 1997-2021 University of Cambridge. ------------------------------------------------------------------------------ @@ -683,84 +688,114 @@ MULTITHREADING In a more complicated situation, where patterns are compiled only when they are first needed, but are still shared between threads, pointers to compiled patterns must be protected from simultaneous writing by - multiple threads, at least until a pattern has been compiled. The logic - can be something like this: + multiple threads. This is somewhat tricky to do correctly. If you know + that writing to a pointer is atomic in your environment, you can use + logic like this: Get a read-only (shared) lock (mutex) for pointer if (pointer == NULL) { Get a write (unique) lock for pointer - pointer = pcre2_compile(... + if (pointer == NULL) pointer = pcre2_compile(... } Release the lock Use pointer in pcre2_match() - Of course, testing for compilation errors should also be included in + Of course, testing for compilation errors should also be included in the code. + The reason for checking the pointer a second time is as follows: Sev- + eral threads may have acquired the shared lock and tested the pointer + for being NULL, but only one of them will be given the write lock, with + the rest kept waiting. The winning thread will compile the pattern and + store the result. After this thread releases the write lock, another + thread will get it, and if it does not retest pointer for being NULL, + will recompile the pattern and overwrite the pointer, creating a memory + leak and possibly causing other issues. + + In an environment where writing to a pointer may not be atomic, the + above logic is not sufficient. The thread that is doing the compiling + may be descheduled after writing only part of the pointer, which could + cause other threads to use an invalid value. Instead of checking the + pointer itself, a separate "pointer is valid" flag (that can be updated + atomically) must be used: + + Get a read-only (shared) lock (mutex) for pointer + if (!pointer_is_valid) + { + Get a write (unique) lock for pointer + if (!pointer_is_valid) + { + pointer = pcre2_compile(... + pointer_is_valid = TRUE + } + } + Release the lock + Use pointer in pcre2_match() + If JIT is being used, but the JIT compilation is not being done immedi- - ately, (perhaps waiting to see if the pattern is used often enough) - similar logic is required. JIT compilation updates a pointer within the - compiled code block, so a thread must gain unique write access to the - pointer before calling pcre2_jit_compile(). Alternatively, - pcre2_code_copy() or pcre2_code_copy_with_tables() can be used to ob- - tain a private copy of the compiled code before calling the JIT com- + ately (perhaps waiting to see if the pattern is used often enough), + similar logic is required. JIT compilation updates a value within the + compiled code block, so a thread must gain unique write access to the + pointer before calling pcre2_jit_compile(). Alternatively, + pcre2_code_copy() or pcre2_code_copy_with_tables() can be used to ob- + tain a private copy of the compiled code before calling the JIT com- piler. Context blocks - The next main section below introduces the idea of "contexts" in which + The next main section below introduces the idea of "contexts" in which PCRE2 functions are called. A context is nothing more than a collection of parameters that control the way PCRE2 operates. Grouping a number of parameters together in a context is a convenient way of passing them to - a PCRE2 function without using lots of arguments. The parameters that - are stored in contexts are in some sense "advanced features" of the + a PCRE2 function without using lots of arguments. The parameters that + are stored in contexts are in some sense "advanced features" of the API. Many straightforward applications will not need to use contexts. In a multithreaded application, if the parameters in a context are val- - ues that are never changed, the same context can be used by all the + ues that are never changed, the same context can be used by all the threads. However, if any thread needs to change any value in a context, it must make its own thread-specific copy. Match blocks - The matching functions need a block of memory for storing the results + The matching functions need a block of memory for storing the results of a match. This includes details of what was matched, as well as addi- - tional information such as the name of a (*MARK) setting. Each thread + tional information such as the name of a (*MARK) setting. Each thread must provide its own copy of this memory. PCRE2 CONTEXTS - Some PCRE2 functions have a lot of parameters, many of which are used - only by specialist applications, for example, those that use custom - memory management or non-standard character tables. To keep function - argument lists at a reasonable size, and at the same time to keep the - API extensible, "uncommon" parameters are passed to certain functions - in a context instead of directly. A context is just a block of memory - that holds the parameter values. Applications that do not need to ad- + Some PCRE2 functions have a lot of parameters, many of which are used + only by specialist applications, for example, those that use custom + memory management or non-standard character tables. To keep function + argument lists at a reasonable size, and at the same time to keep the + API extensible, "uncommon" parameters are passed to certain functions + in a context instead of directly. A context is just a block of memory + that holds the parameter values. Applications that do not need to ad- just any of the context parameters can pass NULL when a context pointer is required. - There are three different types of context: a general context that is - relevant for several PCRE2 operations, a compile-time context, and a + There are three different types of context: a general context that is + relevant for several PCRE2 operations, a compile-time context, and a match-time context. The general context - At present, this context just contains pointers to (and data for) ex- - ternal memory management functions that are called from several places - in the PCRE2 library. The context is named `general' rather than - specifically `memory' because in future other fields may be added. If - you do not want to supply your own custom memory management functions, - you do not need to bother with a general context. A general context is + At present, this context just contains pointers to (and data for) ex- + ternal memory management functions that are called from several places + in the PCRE2 library. The context is named `general' rather than + specifically `memory' because in future other fields may be added. If + you do not want to supply your own custom memory management functions, + you do not need to bother with a general context. A general context is created by: pcre2_general_context *pcre2_general_context_create( void *(*private_malloc)(PCRE2_SIZE, void *), void (*private_free)(void *, void *), void *memory_data); - The two function pointers specify custom memory management functions, + The two function pointers specify custom memory management functions, whose prototypes are: void *private_malloc(PCRE2_SIZE, void *); @@ -768,16 +803,16 @@ PCRE2 CONTEXTS Whenever code in PCRE2 calls these functions, the final argument is the value of memory_data. Either of the first two arguments of the creation - function may be NULL, in which case the system memory management func- - tions malloc() and free() are used. (This is not currently useful, as - there are no other fields in a general context, but in future there - might be.) The private_malloc() function is used (if supplied) to ob- - tain memory for storing the context, and all three values are saved as + function may be NULL, in which case the system memory management func- + tions malloc() and free() are used. (This is not currently useful, as + there are no other fields in a general context, but in future there + might be.) The private_malloc() function is used (if supplied) to ob- + tain memory for storing the context, and all three values are saved as part of the context. - Whenever PCRE2 creates a data block of any kind, the block contains a - pointer to the free() function that matches the malloc() function that - was used. When the time comes to free the block, this function is + Whenever PCRE2 creates a data block of any kind, the block contains a + pointer to the free() function that matches the malloc() function that + was used. When the time comes to free the block, this function is called. A general context can be copied by calling: @@ -789,13 +824,13 @@ PCRE2 CONTEXTS void pcre2_general_context_free(pcre2_general_context *gcontext); - If this function is passed a NULL argument, it returns immediately + If this function is passed a NULL argument, it returns immediately without doing anything. The compile context - A compile context is required if you want to provide an external func- - tion for stack checking during compilation or to change the default + A compile context is required if you want to provide an external func- + tion for stack checking during compilation or to change the default values of any of the following compile-time parameters: What \R matches (Unicode newlines or CR, LF, CRLF only) @@ -805,11 +840,11 @@ PCRE2 CONTEXTS The maximum length of the pattern string The extra options bits (none set by default) - A compile context is also required if you are using custom memory man- - agement. If none of these apply, just pass NULL as the context argu- + A compile context is also required if you are using custom memory man- + agement. If none of these apply, just pass NULL as the context argu- ment of pcre2_compile(). - A compile context is created, copied, and freed by the following func- + A compile context is created, copied, and freed by the following func- tions: pcre2_compile_context *pcre2_compile_context_create( @@ -820,91 +855,91 @@ PCRE2 CONTEXTS void pcre2_compile_context_free(pcre2_compile_context *ccontext); - A compile context is created with default values for its parameters. + A compile context is created with default values for its parameters. These can be changed by calling the following functions, which return 0 on success, or PCRE2_ERROR_BADDATA if invalid data is detected. int pcre2_set_bsr(pcre2_compile_context *ccontext, uint32_t value); - The value must be PCRE2_BSR_ANYCRLF, to specify that \R matches only - CR, LF, or CRLF, or PCRE2_BSR_UNICODE, to specify that \R matches any + The value must be PCRE2_BSR_ANYCRLF, to specify that \R matches only + CR, LF, or CRLF, or PCRE2_BSR_UNICODE, to specify that \R matches any Unicode line ending sequence. The value is used by the JIT compiler and - by the two interpreted matching functions, pcre2_match() and + by the two interpreted matching functions, pcre2_match() and pcre2_dfa_match(). int pcre2_set_character_tables(pcre2_compile_context *ccontext, const uint8_t *tables); - The value must be the result of a call to pcre2_maketables(), whose + The value must be the result of a call to pcre2_maketables(), whose only argument is a general context. This function builds a set of char- acter tables in the current locale. int pcre2_set_compile_extra_options(pcre2_compile_context *ccontext, uint32_t extra_options); - As PCRE2 has developed, almost all the 32 option bits that are avail- - able in the options argument of pcre2_compile() have been used up. To - avoid running out, the compile context contains a set of extra option - bits which are used for some newer, assumed rarer, options. This func- - tion sets those bits. It always sets all the bits (either on or off). - It does not modify any existing setting. The available options are de- + As PCRE2 has developed, almost all the 32 option bits that are avail- + able in the options argument of pcre2_compile() have been used up. To + avoid running out, the compile context contains a set of extra option + bits which are used for some newer, assumed rarer, options. This func- + tion sets those bits. It always sets all the bits (either on or off). + It does not modify any existing setting. The available options are de- fined in the section entitled "Extra compile options" below. int pcre2_set_max_pattern_length(pcre2_compile_context *ccontext, PCRE2_SIZE value); - This sets a maximum length, in code units, for any pattern string that - is compiled with this context. If the pattern is longer, an error is - generated. This facility is provided so that applications that accept + This sets a maximum length, in code units, for any pattern string that + is compiled with this context. If the pattern is longer, an error is + generated. This facility is provided so that applications that accept patterns from external sources can limit their size. The default is the - largest number that a PCRE2_SIZE variable can hold, which is effec- + largest number that a PCRE2_SIZE variable can hold, which is effec- tively unlimited. int pcre2_set_newline(pcre2_compile_context *ccontext, uint32_t value); This specifies which characters or character sequences are to be recog- - nized as newlines. The value must be one of PCRE2_NEWLINE_CR (carriage + nized as newlines. The value must be one of PCRE2_NEWLINE_CR (carriage return only), PCRE2_NEWLINE_LF (linefeed only), PCRE2_NEWLINE_CRLF (the - two-character sequence CR followed by LF), PCRE2_NEWLINE_ANYCRLF (any - of the above), PCRE2_NEWLINE_ANY (any Unicode newline sequence), or + two-character sequence CR followed by LF), PCRE2_NEWLINE_ANYCRLF (any + of the above), PCRE2_NEWLINE_ANY (any Unicode newline sequence), or PCRE2_NEWLINE_NUL (the NUL character, that is a binary zero). A pattern can override the value set in the compile context by starting with a sequence such as (*CRLF). See the pcre2pattern page for details. - When a pattern is compiled with the PCRE2_EXTENDED or PCRE2_EX- - TENDED_MORE option, the newline convention affects the recognition of - the end of internal comments starting with #. The value is saved with - the compiled pattern for subsequent use by the JIT compiler and by the - two interpreted matching functions, pcre2_match() and + When a pattern is compiled with the PCRE2_EXTENDED or PCRE2_EX- + TENDED_MORE option, the newline convention affects the recognition of + the end of internal comments starting with #. The value is saved with + the compiled pattern for subsequent use by the JIT compiler and by the + two interpreted matching functions, pcre2_match() and pcre2_dfa_match(). int pcre2_set_parens_nest_limit(pcre2_compile_context *ccontext, uint32_t value); - This parameter adjusts the limit, set when PCRE2 is built (default - 250), on the depth of parenthesis nesting in a pattern. This limit - stops rogue patterns using up too much system stack when being com- - piled. The limit applies to parentheses of all kinds, not just captur- + This parameter adjusts the limit, set when PCRE2 is built (default + 250), on the depth of parenthesis nesting in a pattern. This limit + stops rogue patterns using up too much system stack when being com- + piled. The limit applies to parentheses of all kinds, not just captur- ing parentheses. int pcre2_set_compile_recursion_guard(pcre2_compile_context *ccontext, int (*guard_function)(uint32_t, void *), void *user_data); - There is at least one application that runs PCRE2 in threads with very - limited system stack, where running out of stack is to be avoided at - all costs. The parenthesis limit above cannot take account of how much - stack is actually available during compilation. For a finer control, - you can supply a function that is called whenever pcre2_compile() - starts to compile a parenthesized part of a pattern. This function can - check the actual stack size (or anything else that it wants to, of + There is at least one application that runs PCRE2 in threads with very + limited system stack, where running out of stack is to be avoided at + all costs. The parenthesis limit above cannot take account of how much + stack is actually available during compilation. For a finer control, + you can supply a function that is called whenever pcre2_compile() + starts to compile a parenthesized part of a pattern. This function can + check the actual stack size (or anything else that it wants to, of course). - The first argument to the callout function gives the current depth of - nesting, and the second is user data that is set up by the last argu- - ment of pcre2_set_compile_recursion_guard(). The callout function + The first argument to the callout function gives the current depth of + nesting, and the second is user data that is set up by the last argu- + ment of pcre2_set_compile_recursion_guard(). The callout function should return zero if all is well, or non-zero to force an error. The match context @@ -918,10 +953,10 @@ PCRE2 CONTEXTS Change the backtracking depth limit Set custom memory management specifically for the match - If none of these apply, just pass NULL as the context argument of + If none of these apply, just pass NULL as the context argument of pcre2_match(), pcre2_dfa_match(), or pcre2_jit_match(). - A match context is created, copied, and freed by the following func- + A match context is created, copied, and freed by the following func- tions: pcre2_match_context *pcre2_match_context_create( @@ -932,7 +967,7 @@ PCRE2 CONTEXTS void pcre2_match_context_free(pcre2_match_context *mcontext); - A match context is created with default values for its parameters. + A match context is created with default values for its parameters. These can be changed by calling the following functions, which return 0 on success, or PCRE2_ERROR_BADDATA if invalid data is detected. @@ -940,7 +975,7 @@ PCRE2 CONTEXTS int (*callout_function)(pcre2_callout_block *, void *), void *callout_data); - This sets up a callout function for PCRE2 to call at specified points + This sets up a callout function for PCRE2 to call at specified points during a matching operation. Details are given in the pcre2callout doc- umentation. @@ -948,34 +983,34 @@ PCRE2 CONTEXTS int (*callout_function)(pcre2_substitute_callout_block *, void *), void *callout_data); - This sets up a callout function for PCRE2 to call after each substitu- + This sets up a callout function for PCRE2 to call after each substitu- tion made by pcre2_substitute(). Details are given in the section enti- tled "Creating a new string with substitutions" below. int pcre2_set_offset_limit(pcre2_match_context *mcontext, PCRE2_SIZE value); - The offset_limit parameter limits how far an unanchored search can ad- - vance in the subject string. The default value is PCRE2_UNSET. The - pcre2_match() and pcre2_dfa_match() functions return PCRE2_ERROR_NO- + The offset_limit parameter limits how far an unanchored search can ad- + vance in the subject string. The default value is PCRE2_UNSET. The + pcre2_match() and pcre2_dfa_match() functions return PCRE2_ERROR_NO- MATCH if a match with a starting point before or at the given offset is not found. The pcre2_substitute() function makes no more substitutions. - For example, if the pattern /abc/ is matched against "123abc" with an - offset limit less than 3, the result is PCRE2_ERROR_NOMATCH. A match - can never be found if the startoffset argument of pcre2_match(), - pcre2_dfa_match(), or pcre2_substitute() is greater than the offset + For example, if the pattern /abc/ is matched against "123abc" with an + offset limit less than 3, the result is PCRE2_ERROR_NOMATCH. A match + can never be found if the startoffset argument of pcre2_match(), + pcre2_dfa_match(), or pcre2_substitute() is greater than the offset limit set in the match context. - When using this facility, you must set the PCRE2_USE_OFFSET_LIMIT op- + When using this facility, you must set the PCRE2_USE_OFFSET_LIMIT op- tion when calling pcre2_compile() so that when JIT is in use, different - code can be compiled. If a match is started with a non-default match + code can be compiled. If a match is started with a non-default match limit when PCRE2_USE_OFFSET_LIMIT is not set, an error is generated. - The offset limit facility can be used to track progress when searching - large subject strings or to limit the extent of global substitutions. - See also the PCRE2_FIRSTLINE option, which requires a match to start - before or at the first newline that follows the start of matching in + The offset limit facility can be used to track progress when searching + large subject strings or to limit the extent of global substitutions. + See also the PCRE2_FIRSTLINE option, which requires a match to start + before or at the first newline that follows the start of matching in the subject. If this is set with an offset limit, a match must occur in the first line and also within the offset limit. In other words, which- ever limit comes first is used. @@ -984,15 +1019,15 @@ PCRE2 CONTEXTS uint32_t value); The heap_limit parameter specifies, in units of kibibytes (1024 bytes), - the maximum amount of heap memory that pcre2_match() may use to hold + the maximum amount of heap memory that pcre2_match() may use to hold backtracking information when running an interpretive match. This limit also applies to pcre2_dfa_match(), which may use the heap when process- - ing patterns with a lot of nested pattern recursion or lookarounds or + ing patterns with a lot of nested pattern recursion or lookarounds or atomic groups. This limit does not apply to matching with the JIT opti- - mization, which has its own memory control arrangements (see the - pcre2jit documentation for more details). If the limit is reached, the - negative error code PCRE2_ERROR_HEAPLIMIT is returned. The default - limit can be set when PCRE2 is built; if it is not, the default is set + mization, which has its own memory control arrangements (see the + pcre2jit documentation for more details). If the limit is reached, the + negative error code PCRE2_ERROR_HEAPLIMIT is returned. The default + limit can be set when PCRE2 is built; if it is not, the default is set very large and is essentially "unlimited". A value for the heap limit may also be supplied by an item at the start @@ -1000,101 +1035,101 @@ PCRE2 CONTEXTS (*LIMIT_HEAP=ddd) - where ddd is a decimal number. However, such a setting is ignored un- - less ddd is less than the limit set by the caller of pcre2_match() or, + where ddd is a decimal number. However, such a setting is ignored un- + less ddd is less than the limit set by the caller of pcre2_match() or, if no such limit is set, less than the default. - The pcre2_match() function starts out using a 20KiB vector on the sys- + The pcre2_match() function starts out using a 20KiB vector on the sys- tem stack for recording backtracking points. The more nested backtrack- - ing points there are (that is, the deeper the search tree), the more - memory is needed. Heap memory is used only if the initial vector is + ing points there are (that is, the deeper the search tree), the more + memory is needed. Heap memory is used only if the initial vector is too small. If the heap limit is set to a value less than 21 (in partic- - ular, zero) no heap memory will be used. In this case, only patterns - that do not have a lot of nested backtracking can be successfully pro- + ular, zero) no heap memory will be used. In this case, only patterns + that do not have a lot of nested backtracking can be successfully pro- cessed. - Similarly, for pcre2_dfa_match(), a vector on the system stack is used - when processing pattern recursions, lookarounds, or atomic groups, and - only if this is not big enough is heap memory used. In this case, too, + Similarly, for pcre2_dfa_match(), a vector on the system stack is used + when processing pattern recursions, lookarounds, or atomic groups, and + only if this is not big enough is heap memory used. In this case, too, setting a value of zero disables the use of the heap. int pcre2_set_match_limit(pcre2_match_context *mcontext, uint32_t value); The match_limit parameter provides a means of preventing PCRE2 from us- - ing up too many computing resources when processing patterns that are + ing up too many computing resources when processing patterns that are not going to match, but which have a very large number of possibilities - in their search trees. The classic example is a pattern that uses + in their search trees. The classic example is a pattern that uses nested unlimited repeats. - There is an internal counter in pcre2_match() that is incremented each - time round its main matching loop. If this value reaches the match + There is an internal counter in pcre2_match() that is incremented each + time round its main matching loop. If this value reaches the match limit, pcre2_match() returns the negative value PCRE2_ERROR_MATCHLIMIT. - This has the effect of limiting the amount of backtracking that can + This has the effect of limiting the amount of backtracking that can take place. For patterns that are not anchored, the count restarts from - zero for each position in the subject string. This limit also applies + zero for each position in the subject string. This limit also applies to pcre2_dfa_match(), though the counting is done in a different way. - When pcre2_match() is called with a pattern that was successfully pro- + When pcre2_match() is called with a pattern that was successfully pro- cessed by pcre2_jit_compile(), the way in which matching is executed is - entirely different. However, there is still the possibility of runaway - matching that goes on for a very long time, and so the match_limit - value is also used in this case (but in a different way) to limit how + entirely different. However, there is still the possibility of runaway + matching that goes on for a very long time, and so the match_limit + value is also used in this case (but in a different way) to limit how long the matching can continue. The default value for the limit can be set when PCRE2 is built; the de- - fault default is 10 million, which handles all but the most extreme - cases. A value for the match limit may also be supplied by an item at + fault default is 10 million, which handles all but the most extreme + cases. A value for the match limit may also be supplied by an item at the start of a pattern of the form (*LIMIT_MATCH=ddd) - where ddd is a decimal number. However, such a setting is ignored un- - less ddd is less than the limit set by the caller of pcre2_match() or + where ddd is a decimal number. However, such a setting is ignored un- + less ddd is less than the limit set by the caller of pcre2_match() or pcre2_dfa_match() or, if no such limit is set, less than the default. int pcre2_set_depth_limit(pcre2_match_context *mcontext, uint32_t value); - This parameter limits the depth of nested backtracking in - pcre2_match(). Each time a nested backtracking point is passed, a new + This parameter limits the depth of nested backtracking in + pcre2_match(). Each time a nested backtracking point is passed, a new memory "frame" is used to remember the state of matching at that point. - Thus, this parameter indirectly limits the amount of memory that is - used in a match. However, because the size of each memory "frame" de- - pends on the number of capturing parentheses, the actual memory limit - varies from pattern to pattern. This limit was more useful in versions + Thus, this parameter indirectly limits the amount of memory that is + used in a match. However, because the size of each memory "frame" de- + pends on the number of capturing parentheses, the actual memory limit + varies from pattern to pattern. This limit was more useful in versions before 10.30, where function recursion was used for backtracking. - The depth limit is not relevant, and is ignored, when matching is done + The depth limit is not relevant, and is ignored, when matching is done using JIT compiled code. However, it is supported by pcre2_dfa_match(), - which uses it to limit the depth of nested internal recursive function - calls that implement atomic groups, lookaround assertions, and pattern + which uses it to limit the depth of nested internal recursive function + calls that implement atomic groups, lookaround assertions, and pattern recursions. This limits, indirectly, the amount of system stack that is - used. It was more useful in versions before 10.32, when stack memory + used. It was more useful in versions before 10.32, when stack memory was used for local workspace vectors for recursive function calls. From - version 10.32, only local variables are allocated on the stack and as + version 10.32, only local variables are allocated on the stack and as each call uses only a few hundred bytes, even a small stack can support quite a lot of recursion. - If the depth of internal recursive function calls is great enough, lo- - cal workspace vectors are allocated on the heap from version 10.32 on- - wards, so the depth limit also indirectly limits the amount of heap + If the depth of internal recursive function calls is great enough, lo- + cal workspace vectors are allocated on the heap from version 10.32 on- + wards, so the depth limit also indirectly limits the amount of heap memory that is used. A recursive pattern such as /(.(?2))((?1)|)/, when - matched to a very long string using pcre2_dfa_match(), can use a great - deal of memory. However, it is probably better to limit heap usage di- + matched to a very long string using pcre2_dfa_match(), can use a great + deal of memory. However, it is probably better to limit heap usage di- rectly by calling pcre2_set_heap_limit(). - The default value for the depth limit can be set when PCRE2 is built; - if it is not, the default is set to the same value as the default for - the match limit. If the limit is exceeded, pcre2_match() or + The default value for the depth limit can be set when PCRE2 is built; + if it is not, the default is set to the same value as the default for + the match limit. If the limit is exceeded, pcre2_match() or pcre2_dfa_match() returns PCRE2_ERROR_DEPTHLIMIT. A value for the depth - limit may also be supplied by an item at the start of a pattern of the + limit may also be supplied by an item at the start of a pattern of the form (*LIMIT_DEPTH=ddd) - where ddd is a decimal number. However, such a setting is ignored un- - less ddd is less than the limit set by the caller of pcre2_match() or + where ddd is a decimal number. However, such a setting is ignored un- + less ddd is less than the limit set by the caller of pcre2_match() or pcre2_dfa_match() or, if no such limit is set, less than the default. @@ -1102,96 +1137,96 @@ CHECKING BUILD-TIME OPTIONS int pcre2_config(uint32_t what, void *where); - The function pcre2_config() makes it possible for a PCRE2 client to - find the value of certain configuration parameters and to discover - which optional features have been compiled into the PCRE2 library. The + The function pcre2_config() makes it possible for a PCRE2 client to + find the value of certain configuration parameters and to discover + which optional features have been compiled into the PCRE2 library. The pcre2build documentation has more details about these features. - The first argument for pcre2_config() specifies which information is + The first argument for pcre2_config() specifies which information is required. The second argument is a pointer to memory into which the in- formation is placed. If NULL is passed, the function returns the amount - of memory that is needed for the requested information. For calls that - return numerical values, the value is in bytes; when requesting these - values, where should point to appropriately aligned memory. For calls - that return strings, the required length is given in code units, not + of memory that is needed for the requested information. For calls that + return numerical values, the value is in bytes; when requesting these + values, where should point to appropriately aligned memory. For calls + that return strings, the required length is given in code units, not counting the terminating zero. - When requesting information, the returned value from pcre2_config() is - non-negative on success, or the negative error code PCRE2_ERROR_BADOP- - TION if the value in the first argument is not recognized. The follow- + When requesting information, the returned value from pcre2_config() is + non-negative on success, or the negative error code PCRE2_ERROR_BADOP- + TION if the value in the first argument is not recognized. The follow- ing information is available: PCRE2_CONFIG_BSR - The output is a uint32_t integer whose value indicates what character - sequences the \R escape sequence matches by default. A value of - PCRE2_BSR_UNICODE means that \R matches any Unicode line ending se- + The output is a uint32_t integer whose value indicates what character + sequences the \R escape sequence matches by default. A value of + PCRE2_BSR_UNICODE means that \R matches any Unicode line ending se- quence; a value of PCRE2_BSR_ANYCRLF means that \R matches only CR, LF, or CRLF. The default can be overridden when a pattern is compiled. PCRE2_CONFIG_COMPILED_WIDTHS - The output is a uint32_t integer whose lower bits indicate which code - unit widths were selected when PCRE2 was built. The 1-bit indicates - 8-bit support, and the 2-bit and 4-bit indicate 16-bit and 32-bit sup- + The output is a uint32_t integer whose lower bits indicate which code + unit widths were selected when PCRE2 was built. The 1-bit indicates + 8-bit support, and the 2-bit and 4-bit indicate 16-bit and 32-bit sup- port, respectively. PCRE2_CONFIG_DEPTHLIMIT - The output is a uint32_t integer that gives the default limit for the - depth of nested backtracking in pcre2_match() or the depth of nested - recursions, lookarounds, and atomic groups in pcre2_dfa_match(). Fur- + The output is a uint32_t integer that gives the default limit for the + depth of nested backtracking in pcre2_match() or the depth of nested + recursions, lookarounds, and atomic groups in pcre2_dfa_match(). Fur- ther details are given with pcre2_set_depth_limit() above. PCRE2_CONFIG_HEAPLIMIT - The output is a uint32_t integer that gives, in kibibytes, the default - limit for the amount of heap memory used by pcre2_match() or - pcre2_dfa_match(). Further details are given with + The output is a uint32_t integer that gives, in kibibytes, the default + limit for the amount of heap memory used by pcre2_match() or + pcre2_dfa_match(). Further details are given with pcre2_set_heap_limit() above. PCRE2_CONFIG_JIT - The output is a uint32_t integer that is set to one if support for + The output is a uint32_t integer that is set to one if support for just-in-time compiling is available; otherwise it is set to zero. PCRE2_CONFIG_JITTARGET - The where argument should point to a buffer that is at least 48 code - units long. (The exact length required can be found by calling - pcre2_config() with where set to NULL.) The buffer is filled with a - string that contains the name of the architecture for which the JIT - compiler is configured, for example "x86 32bit (little endian + un- - aligned)". If JIT support is not available, PCRE2_ERROR_BADOPTION is - returned, otherwise the number of code units used is returned. This is + The where argument should point to a buffer that is at least 48 code + units long. (The exact length required can be found by calling + pcre2_config() with where set to NULL.) The buffer is filled with a + string that contains the name of the architecture for which the JIT + compiler is configured, for example "x86 32bit (little endian + un- + aligned)". If JIT support is not available, PCRE2_ERROR_BADOPTION is + returned, otherwise the number of code units used is returned. This is the length of the string, plus one unit for the terminating zero. PCRE2_CONFIG_LINKSIZE The output is a uint32_t integer that contains the number of bytes used - for internal linkage in compiled regular expressions. When PCRE2 is - configured, the value can be set to 2, 3, or 4, with the default being - 2. This is the value that is returned by pcre2_config(). However, when - the 16-bit library is compiled, a value of 3 is rounded up to 4, and - when the 32-bit library is compiled, internal linkages always use 4 + for internal linkage in compiled regular expressions. When PCRE2 is + configured, the value can be set to 2, 3, or 4, with the default being + 2. This is the value that is returned by pcre2_config(). However, when + the 16-bit library is compiled, a value of 3 is rounded up to 4, and + when the 32-bit library is compiled, internal linkages always use 4 bytes, so the configured value is not relevant. The default value of 2 for the 8-bit and 16-bit libraries is sufficient - for all but the most massive patterns, since it allows the size of the - compiled pattern to be up to 65535 code units. Larger values allow - larger regular expressions to be compiled by those two libraries, but + for all but the most massive patterns, since it allows the size of the + compiled pattern to be up to 65535 code units. Larger values allow + larger regular expressions to be compiled by those two libraries, but at the expense of slower matching. PCRE2_CONFIG_MATCHLIMIT The output is a uint32_t integer that gives the default match limit for - pcre2_match(). Further details are given with pcre2_set_match_limit() + pcre2_match(). Further details are given with pcre2_set_match_limit() above. PCRE2_CONFIG_NEWLINE - The output is a uint32_t integer whose value specifies the default - character sequence that is recognized as meaning "newline". The values + The output is a uint32_t integer whose value specifies the default + character sequence that is recognized as meaning "newline". The values are: PCRE2_NEWLINE_CR Carriage return (CR) @@ -1201,23 +1236,23 @@ CHECKING BUILD-TIME OPTIONS PCRE2_NEWLINE_ANYCRLF Any of CR, LF, or CRLF PCRE2_NEWLINE_NUL The NUL character (binary zero) - The default should normally correspond to the standard sequence for + The default should normally correspond to the standard sequence for your operating system. PCRE2_CONFIG_NEVER_BACKSLASH_C - The output is a uint32_t integer that is set to one if the use of \C - was permanently disabled when PCRE2 was built; otherwise it is set to + The output is a uint32_t integer that is set to one if the use of \C + was permanently disabled when PCRE2 was built; otherwise it is set to zero. PCRE2_CONFIG_PARENSLIMIT - The output is a uint32_t integer that gives the maximum depth of nest- + The output is a uint32_t integer that gives the maximum depth of nest- ing of parentheses (of any kind) in a pattern. This limit is imposed to - cap the amount of system stack used when a pattern is compiled. It is - specified when PCRE2 is built; the default is 250. This limit does not + cap the amount of system stack used when a pattern is compiled. It is + specified when PCRE2 is built; the default is 250. This limit does not take into account the stack that may already be used by the calling ap- - plication. For finer control over compilation stack usage, see + plication. For finer control over compilation stack usage, see pcre2_set_compile_recursion_guard(). PCRE2_CONFIG_STACKRECURSE @@ -1228,30 +1263,30 @@ CHECKING BUILD-TIME OPTIONS PCRE2_CONFIG_TABLES_LENGTH The output is a uint32_t integer that gives the length of PCRE2's char- - acter processing tables in bytes. For details of these tables see the + acter processing tables in bytes. For details of these tables see the section on locale support below. PCRE2_CONFIG_UNICODE_VERSION - The where argument should point to a buffer that is at least 24 code - units long. (The exact length required can be found by calling - pcre2_config() with where set to NULL.) If PCRE2 has been compiled - without Unicode support, the buffer is filled with the text "Unicode - not supported". Otherwise, the Unicode version string (for example, - "8.0.0") is inserted. The number of code units used is returned. This + The where argument should point to a buffer that is at least 24 code + units long. (The exact length required can be found by calling + pcre2_config() with where set to NULL.) If PCRE2 has been compiled + without Unicode support, the buffer is filled with the text "Unicode + not supported". Otherwise, the Unicode version string (for example, + "8.0.0") is inserted. The number of code units used is returned. This is the length of the string plus one unit for the terminating zero. PCRE2_CONFIG_UNICODE - The output is a uint32_t integer that is set to one if Unicode support - is available; otherwise it is set to zero. Unicode support implies UTF + The output is a uint32_t integer that is set to one if Unicode support + is available; otherwise it is set to zero. Unicode support implies UTF support. PCRE2_CONFIG_VERSION - The where argument should point to a buffer that is at least 24 code - units long. (The exact length required can be found by calling - pcre2_config() with where set to NULL.) The buffer is filled with the + The where argument should point to a buffer that is at least 24 code + units long. (The exact length required can be found by calling + pcre2_config() with where set to NULL.) The buffer is filled with the PCRE2 version string, zero-terminated. The number of code units used is returned. This is the length of the string plus one unit for the termi- nating zero. @@ -1269,103 +1304,103 @@ COMPILING A PATTERN pcre2_code *pcre2_code_copy_with_tables(const pcre2_code *code); - The pcre2_compile() function compiles a pattern into an internal form. - The pattern is defined by a pointer to a string of code units and a - length (in code units). If the pattern is zero-terminated, the length - can be specified as PCRE2_ZERO_TERMINATED. The function returns a + The pcre2_compile() function compiles a pattern into an internal form. + The pattern is defined by a pointer to a string of code units and a + length (in code units). If the pattern is zero-terminated, the length + can be specified as PCRE2_ZERO_TERMINATED. The function returns a pointer to a block of memory that contains the compiled pattern and re- lated data, or NULL if an error occurred. - If the compile context argument ccontext is NULL, memory for the com- - piled pattern is obtained by calling malloc(). Otherwise, it is ob- + If the compile context argument ccontext is NULL, memory for the com- + piled pattern is obtained by calling malloc(). Otherwise, it is ob- tained from the same memory function that was used for the compile con- text. The caller must free the memory by calling pcre2_code_free() when it is no longer needed. If pcre2_code_free() is called with a NULL ar- gument, it returns immediately, without doing anything. The function pcre2_code_copy() makes a copy of the compiled code in new - memory, using the same memory allocator as was used for the original. - However, if the code has been processed by the JIT compiler (see be- - low), the JIT information cannot be copied (because it is position-de- - pendent). The new copy can initially be used only for non-JIT match- - ing, though it can be passed to pcre2_jit_compile() if required. If + memory, using the same memory allocator as was used for the original. + However, if the code has been processed by the JIT compiler (see be- + low), the JIT information cannot be copied (because it is position-de- + pendent). The new copy can initially be used only for non-JIT match- + ing, though it can be passed to pcre2_jit_compile() if required. If pcre2_code_copy() is called with a NULL argument, it returns NULL. The pcre2_code_copy() function provides a way for individual threads in - a multithreaded application to acquire a private copy of shared com- - piled code. However, it does not make a copy of the character tables - used by the compiled pattern; the new pattern code points to the same - tables as the original code. (See "Locale Support" below for details - of these character tables.) In many applications the same tables are - used throughout, so this behaviour is appropriate. Nevertheless, there + a multithreaded application to acquire a private copy of shared com- + piled code. However, it does not make a copy of the character tables + used by the compiled pattern; the new pattern code points to the same + tables as the original code. (See "Locale Support" below for details + of these character tables.) In many applications the same tables are + used throughout, so this behaviour is appropriate. Nevertheless, there are occasions when a copy of a compiled pattern and the relevant tables - are needed. The pcre2_code_copy_with_tables() provides this facility. - Copies of both the code and the tables are made, with the new code - pointing to the new tables. The memory for the new tables is automati- - cally freed when pcre2_code_free() is called for the new copy of the - compiled code. If pcre2_code_copy_with_tables() is called with a NULL + are needed. The pcre2_code_copy_with_tables() provides this facility. + Copies of both the code and the tables are made, with the new code + pointing to the new tables. The memory for the new tables is automati- + cally freed when pcre2_code_free() is called for the new copy of the + compiled code. If pcre2_code_copy_with_tables() is called with a NULL argument, it returns NULL. - NOTE: When one of the matching functions is called, pointers to the + NOTE: When one of the matching functions is called, pointers to the compiled pattern and the subject string are set in the match data block - so that they can be referenced by the substring extraction functions - after a successful match. After running a match, you must not free a - compiled pattern or a subject string until after all operations on the - match data block have taken place, unless, in the case of the subject - string, you have used the PCRE2_COPY_MATCHED_SUBJECT option, which is - described in the section entitled "Option bits for pcre2_match()" be- + so that they can be referenced by the substring extraction functions + after a successful match. After running a match, you must not free a + compiled pattern or a subject string until after all operations on the + match data block have taken place, unless, in the case of the subject + string, you have used the PCRE2_COPY_MATCHED_SUBJECT option, which is + described in the section entitled "Option bits for pcre2_match()" be- low. - The options argument for pcre2_compile() contains various bit settings - that affect the compilation. It should be zero if none of them are re- - quired. The available options are described below. Some of them (in - particular, those that are compatible with Perl, but some others as - well) can also be set and unset from within the pattern (see the de- + The options argument for pcre2_compile() contains various bit settings + that affect the compilation. It should be zero if none of them are re- + quired. The available options are described below. Some of them (in + particular, those that are compatible with Perl, but some others as + well) can also be set and unset from within the pattern (see the de- tailed description in the pcre2pattern documentation). - For those options that can be different in different parts of the pat- - tern, the contents of the options argument specifies their settings at - the start of compilation. The PCRE2_ANCHORED, PCRE2_ENDANCHORED, and - PCRE2_NO_UTF_CHECK options can be set at the time of matching as well + For those options that can be different in different parts of the pat- + tern, the contents of the options argument specifies their settings at + the start of compilation. The PCRE2_ANCHORED, PCRE2_ENDANCHORED, and + PCRE2_NO_UTF_CHECK options can be set at the time of matching as well as at compile time. - Some additional options and less frequently required compile-time pa- - rameters (for example, the newline setting) can be provided in a com- + Some additional options and less frequently required compile-time pa- + rameters (for example, the newline setting) can be provided in a com- pile context (as described above). If errorcode or erroroffset is NULL, pcre2_compile() returns NULL imme- - diately. Otherwise, the variables to which these point are set to an + diately. Otherwise, the variables to which these point are set to an error code and an offset (number of code units) within the pattern, re- spectively, when pcre2_compile() returns NULL because a compilation er- - ror has occurred. The values are not defined when compilation is suc- + ror has occurred. The values are not defined when compilation is suc- cessful and pcre2_compile() returns a non-NULL value. - There are nearly 100 positive error codes that pcre2_compile() may re- - turn if it finds an error in the pattern. There are also some negative - error codes that are used for invalid UTF strings when validity check- - ing is in force. These are the same as given by pcre2_match() and + There are nearly 100 positive error codes that pcre2_compile() may re- + turn if it finds an error in the pattern. There are also some negative + error codes that are used for invalid UTF strings when validity check- + ing is in force. These are the same as given by pcre2_match() and pcre2_dfa_match(), and are described in the pcre2unicode documentation. - There is no separate documentation for the positive error codes, be- - cause the textual error messages that are obtained by calling the + There is no separate documentation for the positive error codes, be- + cause the textual error messages that are obtained by calling the pcre2_get_error_message() function (see "Obtaining a textual error mes- - sage" below) should be self-explanatory. Macro names starting with - PCRE2_ERROR_ are defined for both positive and negative error codes in + sage" below) should be self-explanatory. Macro names starting with + PCRE2_ERROR_ are defined for both positive and negative error codes in pcre2.h. The value returned in erroroffset is an indication of where in the pat- - tern the error occurred. It is not necessarily the furthest point in + tern the error occurred. It is not necessarily the furthest point in the pattern that was read. For example, after the error "lookbehind as- - sertion is not fixed length", the error offset points to the start of - the failing assertion. For an invalid UTF-8 or UTF-16 string, the off- + sertion is not fixed length", the error offset points to the start of + the failing assertion. For an invalid UTF-8 or UTF-16 string, the off- set is that of the first code unit of the failing character. - Some errors are not detected until the whole pattern has been scanned; - in these cases, the offset passed back is the length of the pattern. - Note that the offset is in code units, not characters, even in a UTF + Some errors are not detected until the whole pattern has been scanned; + in these cases, the offset passed back is the length of the pattern. + Note that the offset is in code units, not characters, even in a UTF mode. It may sometimes point into the middle of a UTF-8 or UTF-16 char- acter. - This code fragment shows a typical straightforward call to pcre2_com- + This code fragment shows a typical straightforward call to pcre2_com- pile(): pcre2_code *re; @@ -1382,92 +1417,95 @@ COMPILING A PATTERN Main compile options - The following names for option bits are defined in the pcre2.h header + The following names for option bits are defined in the pcre2.h header file: PCRE2_ANCHORED If this bit is set, the pattern is forced to be "anchored", that is, it - is constrained to match only at the first matching point in the string - that is being searched (the "subject string"). This effect can also be - achieved by appropriate constructs in the pattern itself, which is the + is constrained to match only at the first matching point in the string + that is being searched (the "subject string"). This effect can also be + achieved by appropriate constructs in the pattern itself, which is the only way to do it in Perl. PCRE2_ALLOW_EMPTY_CLASS - By default, for compatibility with Perl, a closing square bracket that - immediately follows an opening one is treated as a data character for - the class. When PCRE2_ALLOW_EMPTY_CLASS is set, it terminates the + By default, for compatibility with Perl, a closing square bracket that + immediately follows an opening one is treated as a data character for + the class. When PCRE2_ALLOW_EMPTY_CLASS is set, it terminates the class, which therefore contains no characters and so can never match. PCRE2_ALT_BSUX - This option request alternative handling of three escape sequences, - which makes PCRE2's behaviour more like ECMAscript (aka JavaScript). + This option request alternative handling of three escape sequences, + which makes PCRE2's behaviour more like ECMAscript (aka JavaScript). When it is set: (1) \U matches an upper case "U" character; by default \U causes a com- pile time error (Perl uses \U to upper case subsequent characters). (2) \u matches a lower case "u" character unless it is followed by four - hexadecimal digits, in which case the hexadecimal number defines the - code point to match. By default, \u causes a compile time error (Perl + hexadecimal digits, in which case the hexadecimal number defines the + code point to match. By default, \u causes a compile time error (Perl uses it to upper case the following character). - (3) \x matches a lower case "x" character unless it is followed by two - hexadecimal digits, in which case the hexadecimal number defines the - code point to match. By default, as in Perl, a hexadecimal number is + (3) \x matches a lower case "x" character unless it is followed by two + hexadecimal digits, in which case the hexadecimal number defines the + code point to match. By default, as in Perl, a hexadecimal number is always expected after \x, but it may have zero, one, or two digits (so, for example, \xz matches a binary zero character followed by z). ECMAscript 6 added additional functionality to \u. This can be accessed - using the PCRE2_EXTRA_ALT_BSUX extra option (see "Extra compile op- + using the PCRE2_EXTRA_ALT_BSUX extra option (see "Extra compile op- tions" below). Note that this alternative escape handling applies only - to patterns. Neither of these options affects the processing of re- + to patterns. Neither of these options affects the processing of re- placement strings passed to pcre2_substitute(). PCRE2_ALT_CIRCUMFLEX In multiline mode (when PCRE2_MULTILINE is set), the circumflex - metacharacter matches at the start of the subject (unless PCRE2_NOTBOL - is set), and also after any internal newline. However, it does not + metacharacter matches at the start of the subject (unless PCRE2_NOTBOL + is set), and also after any internal newline. However, it does not match after a newline at the end of the subject, for compatibility with - Perl. If you want a multiline circumflex also to match after a termi- + Perl. If you want a multiline circumflex also to match after a termi- nating newline, you must set PCRE2_ALT_CIRCUMFLEX. PCRE2_ALT_VERBNAMES - By default, for compatibility with Perl, the name in any verb sequence - such as (*MARK:NAME) is any sequence of characters that does not in- - clude a closing parenthesis. The name is not processed in any way, and - it is not possible to include a closing parenthesis in the name. How- - ever, if the PCRE2_ALT_VERBNAMES option is set, normal backslash pro- - cessing is applied to verb names and only an unescaped closing paren- - thesis terminates the name. A closing parenthesis can be included in a - name either as \) or between \Q and \E. If the PCRE2_EXTENDED or - PCRE2_EXTENDED_MORE option is set with PCRE2_ALT_VERBNAMES, unescaped - whitespace in verb names is skipped and #-comments are recognized, ex- + By default, for compatibility with Perl, the name in any verb sequence + such as (*MARK:NAME) is any sequence of characters that does not in- + clude a closing parenthesis. The name is not processed in any way, and + it is not possible to include a closing parenthesis in the name. How- + ever, if the PCRE2_ALT_VERBNAMES option is set, normal backslash pro- + cessing is applied to verb names and only an unescaped closing paren- + thesis terminates the name. A closing parenthesis can be included in a + name either as \) or between \Q and \E. If the PCRE2_EXTENDED or + PCRE2_EXTENDED_MORE option is set with PCRE2_ALT_VERBNAMES, unescaped + whitespace in verb names is skipped and #-comments are recognized, ex- actly as in the rest of the pattern. PCRE2_AUTO_CALLOUT - If this bit is set, pcre2_compile() automatically inserts callout - items, all with number 255, before each pattern item, except immedi- - ately before or after an explicit callout in the pattern. For discus- + If this bit is set, pcre2_compile() automatically inserts callout + items, all with number 255, before each pattern item, except immedi- + ately before or after an explicit callout in the pattern. For discus- sion of the callout facility, see the pcre2callout documentation. PCRE2_CASELESS - If this bit is set, letters in the pattern match both upper and lower - case letters in the subject. It is equivalent to Perl's /i option, and - it can be changed within a pattern by a (?i) option setting. If either - PCRE2_UTF or PCRE2_UCP is set, Unicode properties are used for all - characters with more than one other case, and for all characters whose - code points are greater than U+007F. For lower valued characters with - only one other case, a lookup table is used for speed. When neither - PCRE2_UTF nor PCRE2_UCP is set, a lookup table is used for all code - points less than 256, and higher code points (available only in 16-bit - or 32-bit mode) are treated as not having another case. + If this bit is set, letters in the pattern match both upper and lower + case letters in the subject. It is equivalent to Perl's /i option, and + it can be changed within a pattern by a (?i) option setting. If either + PCRE2_UTF or PCRE2_UCP is set, Unicode properties are used for all + characters with more than one other case, and for all characters whose + code points are greater than U+007F. Note that there are two ASCII + characters, K and S, that, in addition to their lower case ASCII equiv- + alents, are case-equivalent with U+212A (Kelvin sign) and U+017F (long + S) respectively. For lower valued characters with only one other case, + a lookup table is used for speed. When neither PCRE2_UTF nor PCRE2_UCP + is set, a lookup table is used for all code points less than 256, and + higher code points (available only in 16-bit or 32-bit mode) are + treated as not having another case. PCRE2_DOLLAR_ENDONLY @@ -1839,86 +1877,93 @@ COMPILING A PATTERN The option bits that can be set in a compile context by calling the pcre2_set_compile_extra_options() function are as follows: + PCRE2_EXTRA_ALLOW_LOOKAROUND_BSK + + Since release 10.38 PCRE2 has forbidden the use of \K within lookaround + assertions, following Perl's lead. This option is provided to re-enable + the previous behaviour (act in positive lookarounds, ignore in negative + ones) in case anybody is relying on it. + PCRE2_EXTRA_ALLOW_SURROGATE_ESCAPES - This option applies when compiling a pattern in UTF-8 or UTF-32 mode. - It is forbidden in UTF-16 mode, and ignored in non-UTF modes. Unicode + This option applies when compiling a pattern in UTF-8 or UTF-32 mode. + It is forbidden in UTF-16 mode, and ignored in non-UTF modes. Unicode "surrogate" code points in the range 0xd800 to 0xdfff are used in pairs - in UTF-16 to encode code points with values in the range 0x10000 to - 0x10ffff. The surrogates cannot therefore be represented in UTF-16. + in UTF-16 to encode code points with values in the range 0x10000 to + 0x10ffff. The surrogates cannot therefore be represented in UTF-16. They can be represented in UTF-8 and UTF-32, but are defined as invalid - code points, and cause errors if encountered in a UTF-8 or UTF-32 + code points, and cause errors if encountered in a UTF-8 or UTF-32 string that is being checked for validity by PCRE2. - These values also cause errors if encountered in escape sequences such + These values also cause errors if encountered in escape sequences such as \x{d912} within a pattern. However, it seems that some applications, when using PCRE2 to check for unwanted characters in UTF-8 strings, ex- - plicitly test for the surrogates using escape sequences. The - PCRE2_NO_UTF_CHECK option does not disable the error that occurs, be- + plicitly test for the surrogates using escape sequences. The + PCRE2_NO_UTF_CHECK option does not disable the error that occurs, be- cause it applies only to the testing of input strings for UTF validity. - If the extra option PCRE2_EXTRA_ALLOW_SURROGATE_ESCAPES is set, surro- - gate code point values in UTF-8 and UTF-32 patterns no longer provoke - errors and are incorporated in the compiled pattern. However, they can - only match subject characters if the matching function is called with + If the extra option PCRE2_EXTRA_ALLOW_SURROGATE_ESCAPES is set, surro- + gate code point values in UTF-8 and UTF-32 patterns no longer provoke + errors and are incorporated in the compiled pattern. However, they can + only match subject characters if the matching function is called with PCRE2_NO_UTF_CHECK set. PCRE2_EXTRA_ALT_BSUX - The original option PCRE2_ALT_BSUX causes PCRE2 to process \U, \u, and - \x in the way that ECMAscript (aka JavaScript) does. Additional func- + The original option PCRE2_ALT_BSUX causes PCRE2 to process \U, \u, and + \x in the way that ECMAscript (aka JavaScript) does. Additional func- tionality was defined by ECMAscript 6; setting PCRE2_EXTRA_ALT_BSUX has - the effect of PCRE2_ALT_BSUX, but in addition it recognizes \u{hhh..} + the effect of PCRE2_ALT_BSUX, but in addition it recognizes \u{hhh..} as a hexadecimal character code, where hhh.. is any number of hexadeci- mal digits. PCRE2_EXTRA_BAD_ESCAPE_IS_LITERAL - This is a dangerous option. Use with care. By default, an unrecognized - escape such as \j or a malformed one such as \x{2z} causes a compile- + This is a dangerous option. Use with care. By default, an unrecognized + escape such as \j or a malformed one such as \x{2z} causes a compile- time error when detected by pcre2_compile(). Perl is somewhat inconsis- - tent in handling such items: for example, \j is treated as a literal - "j", and non-hexadecimal digits in \x{} are just ignored, though warn- - ings are given in both cases if Perl's warning switch is enabled. How- - ever, a malformed octal number after \o{ always causes an error in + tent in handling such items: for example, \j is treated as a literal + "j", and non-hexadecimal digits in \x{} are just ignored, though warn- + ings are given in both cases if Perl's warning switch is enabled. How- + ever, a malformed octal number after \o{ always causes an error in Perl. - If the PCRE2_EXTRA_BAD_ESCAPE_IS_LITERAL extra option is passed to - pcre2_compile(), all unrecognized or malformed escape sequences are - treated as single-character escapes. For example, \j is a literal "j" - and \x{2z} is treated as the literal string "x{2z}". Setting this op- + If the PCRE2_EXTRA_BAD_ESCAPE_IS_LITERAL extra option is passed to + pcre2_compile(), all unrecognized or malformed escape sequences are + treated as single-character escapes. For example, \j is a literal "j" + and \x{2z} is treated as the literal string "x{2z}". Setting this op- tion means that typos in patterns may go undetected and have unexpected - results. Also note that a sequence such as [\N{] is interpreted as a - malformed attempt at [\N{...}] and so is treated as [N{] whereas [\N] + results. Also note that a sequence such as [\N{] is interpreted as a + malformed attempt at [\N{...}] and so is treated as [N{] whereas [\N] gives an error because an unqualified \N is a valid escape sequence but - is not supported in a character class. To reiterate: this is a danger- + is not supported in a character class. To reiterate: this is a danger- ous option. Use with great care. PCRE2_EXTRA_ESCAPED_CR_IS_LF - There are some legacy applications where the escape sequence \r in a - pattern is expected to match a newline. If this option is set, \r in a - pattern is converted to \n so that it matches a LF (linefeed) instead - of a CR (carriage return) character. The option does not affect a lit- - eral CR in the pattern, nor does it affect CR specified as an explicit + There are some legacy applications where the escape sequence \r in a + pattern is expected to match a newline. If this option is set, \r in a + pattern is converted to \n so that it matches a LF (linefeed) instead + of a CR (carriage return) character. The option does not affect a lit- + eral CR in the pattern, nor does it affect CR specified as an explicit code point such as \x{0D}. PCRE2_EXTRA_MATCH_LINE - This option is provided for use by the -x option of pcre2grep. It - causes the pattern only to match complete lines. This is achieved by - automatically inserting the code for "^(?:" at the start of the com- - piled pattern and ")$" at the end. Thus, when PCRE2_MULTILINE is set, - the matched line may be in the middle of the subject string. This op- + This option is provided for use by the -x option of pcre2grep. It + causes the pattern only to match complete lines. This is achieved by + automatically inserting the code for "^(?:" at the start of the com- + piled pattern and ")$" at the end. Thus, when PCRE2_MULTILINE is set, + the matched line may be in the middle of the subject string. This op- tion can be used with PCRE2_LITERAL. PCRE2_EXTRA_MATCH_WORD - This option is provided for use by the -w option of pcre2grep. It - causes the pattern only to match strings that have a word boundary at - the start and the end. This is achieved by automatically inserting the - code for "\b(?:" at the start of the compiled pattern and ")\b" at the - end. The option may be used with PCRE2_LITERAL. However, it is ignored + This option is provided for use by the -w option of pcre2grep. It + causes the pattern only to match strings that have a word boundary at + the start and the end. This is achieved by automatically inserting the + code for "\b(?:" at the start of the compiled pattern and ")\b" at the + end. The option may be used with PCRE2_LITERAL. However, it is ignored if PCRE2_EXTRA_MATCH_LINE is also set. @@ -1941,16 +1986,16 @@ JUST-IN-TIME (JIT) COMPILATION void pcre2_jit_stack_free(pcre2_jit_stack *jit_stack); - These functions provide support for JIT compilation, which, if the - just-in-time compiler is available, further processes a compiled pat- + These functions provide support for JIT compilation, which, if the + just-in-time compiler is available, further processes a compiled pat- tern into machine code that executes much faster than the pcre2_match() - interpretive matching function. Full details are given in the pcre2jit + interpretive matching function. Full details are given in the pcre2jit documentation. - JIT compilation is a heavyweight optimization. It can take some time - for patterns to be analyzed, and for one-off matches and simple pat- - terns the benefit of faster execution might be offset by a much slower - compilation time. Most (but not all) patterns can be optimized by the + JIT compilation is a heavyweight optimization. It can take some time + for patterns to be analyzed, and for one-off matches and simple pat- + terns the benefit of faster execution might be offset by a much slower + compilation time. Most (but not all) patterns can be optimized by the JIT compiler. @@ -1961,46 +2006,46 @@ LOCALE SUPPORT void pcre2_maketables_free(pcre2_general_context *gcontext, const uint8_t *tables); - PCRE2 handles caseless matching, and determines whether characters are - letters, digits, or whatever, by reference to a set of tables, indexed + PCRE2 handles caseless matching, and determines whether characters are + letters, digits, or whatever, by reference to a set of tables, indexed by character code point. However, this applies only to characters whose - code points are less than 256. By default, higher-valued code points + code points are less than 256. By default, higher-valued code points never match escapes such as \w or \d. - When PCRE2 is built with Unicode support (the default), the Unicode + When PCRE2 is built with Unicode support (the default), the Unicode properties of all characters can be tested with \p and \P, or, alterna- - tively, the PCRE2_UCP option can be set when a pattern is compiled; - this causes \w and friends to use Unicode property support instead of - the built-in tables. PCRE2_UCP also causes upper/lower casing opera- - tions on characters with code points greater than 127 to use Unicode + tively, the PCRE2_UCP option can be set when a pattern is compiled; + this causes \w and friends to use Unicode property support instead of + the built-in tables. PCRE2_UCP also causes upper/lower casing opera- + tions on characters with code points greater than 127 to use Unicode properties. These effects apply even when PCRE2_UTF is not set. - The use of locales with Unicode is discouraged. If you are handling - characters with code points greater than 127, you should either use + The use of locales with Unicode is discouraged. If you are handling + characters with code points greater than 127, you should either use Unicode support, or use locales, but not try to mix the two. - PCRE2 contains a built-in set of character tables that are used by de- - fault. These are sufficient for many applications. Normally, the in- - ternal tables recognize only ASCII characters. However, when PCRE2 is + PCRE2 contains a built-in set of character tables that are used by de- + fault. These are sufficient for many applications. Normally, the in- + ternal tables recognize only ASCII characters. However, when PCRE2 is built, it is possible to cause the internal tables to be rebuilt in the default "C" locale of the local system, which may cause them to be dif- ferent. - The built-in tables can be overridden by tables supplied by the appli- - cation that calls PCRE2. These may be created in a different locale - from the default. As more and more applications change to using Uni- + The built-in tables can be overridden by tables supplied by the appli- + cation that calls PCRE2. These may be created in a different locale + from the default. As more and more applications change to using Uni- code, the need for this locale support is expected to die away. - External tables are built by calling the pcre2_maketables() function, + External tables are built by calling the pcre2_maketables() function, in the relevant locale. The only argument to this function is a general - context, which can be used to pass a custom memory allocator. If the + context, which can be used to pass a custom memory allocator. If the argument is NULL, the system malloc() is used. The result can be passed to pcre2_compile() as often as necessary, by creating a compile context - and calling pcre2_set_character_tables() to set the tables pointer + and calling pcre2_set_character_tables() to set the tables pointer therein. - For example, to build and use tables that are appropriate for the - French locale (where accented characters with values greater than 127 + For example, to build and use tables that are appropriate for the + French locale (where accented characters with values greater than 127 are treated as letters), the following code could be used: setlocale(LC_CTYPE, "fr_FR"); @@ -2009,31 +2054,31 @@ LOCALE SUPPORT pcre2_set_character_tables(ccontext, tables); re = pcre2_compile(..., ccontext); - The locale name "fr_FR" is used on Linux and other Unix-like systems; + The locale name "fr_FR" is used on Linux and other Unix-like systems; if you are using Windows, the name for the French locale is "french". The pointer that is passed (via the compile context) to pcre2_compile() is saved with the compiled pattern, and the same tables are used by the - matching functions. Thus, for any single pattern, compilation and - matching both happen in the same locale, but different patterns can be + matching functions. Thus, for any single pattern, compilation and + matching both happen in the same locale, but different patterns can be processed in different locales. - It is the caller's responsibility to ensure that the memory containing + It is the caller's responsibility to ensure that the memory containing the tables remains available while they are still in use. When they are - no longer needed, you can discard them using pcre2_maketables_free(), - which should pass as its first parameter the same global context that + no longer needed, you can discard them using pcre2_maketables_free(), + which should pass as its first parameter the same global context that was used to create the tables. Saving locale tables - The tables described above are just a sequence of binary bytes, which - makes them independent of hardware characteristics such as endianness - or whether the processor is 32-bit or 64-bit. A copy of the result of - pcre2_maketables() can therefore be saved in a file or elsewhere and - re-used later, even in a different program or on another computer. The - size of the tables (number of bytes) must be obtained by calling - pcre2_config() with the PCRE2_CONFIG_TABLES_LENGTH option because - pcre2_maketables() does not return this value. Note that the + The tables described above are just a sequence of binary bytes, which + makes them independent of hardware characteristics such as endianness + or whether the processor is 32-bit or 64-bit. A copy of the result of + pcre2_maketables() can therefore be saved in a file or elsewhere and + re-used later, even in a different program or on another computer. The + size of the tables (number of bytes) must be obtained by calling + pcre2_config() with the PCRE2_CONFIG_TABLES_LENGTH option because + pcre2_maketables() does not return this value. Note that the pcre2_dftables program, which is part of the PCRE2 build system, can be used stand-alone to create a file that contains a set of binary tables. See the pcre2build documentation for details. @@ -2043,13 +2088,13 @@ INFORMATION ABOUT A COMPILED PATTERN int pcre2_pattern_info(const pcre2 *code, uint32_t what, void *where); - The pcre2_pattern_info() function returns general information about a + The pcre2_pattern_info() function returns general information about a compiled pattern. For information about callouts, see the next section. - The first argument for pcre2_pattern_info() is a pointer to the com- + The first argument for pcre2_pattern_info() is a pointer to the com- piled pattern. The second argument specifies which piece of information - is required, and the third argument is a pointer to a variable to re- - ceive the data. If the third argument is NULL, the first argument is - ignored, and the function returns the size in bytes of the variable + is required, and the third argument is a pointer to a variable to re- + ceive the data. If the third argument is NULL, the first argument is + ignored, and the function returns the size in bytes of the variable that is required for the information requested. Otherwise, the yield of the function is zero for success, or one of the following negative num- bers: @@ -2060,8 +2105,8 @@ INFORMATION ABOUT A COMPILED PATTERN PCRE2_ERROR_UNSET the requested field is not set The "magic number" is placed at the start of each compiled pattern as a - simple check against passing an arbitrary memory pointer. Here is a - typical call of pcre2_pattern_info(), to obtain the length of the com- + simple check against passing an arbitrary memory pointer. Here is a + typical call of pcre2_pattern_info(), to obtain the length of the com- piled pattern: int rc; @@ -2079,22 +2124,22 @@ INFORMATION ABOUT A COMPILED PATTERN PCRE2_INFO_EXTRAOPTIONS Return copies of the pattern's options. The third argument should point - to a uint32_t variable. PCRE2_INFO_ARGOPTIONS returns exactly the op- - tions that were passed to pcre2_compile(), whereas PCRE2_INFO_ALLOP- - TIONS returns the compile options as modified by any top-level (*XXX) - option settings such as (*UTF) at the start of the pattern itself. - PCRE2_INFO_EXTRAOPTIONS returns the extra options that were set in the - compile context by calling the pcre2_set_compile_extra_options() func- + to a uint32_t variable. PCRE2_INFO_ARGOPTIONS returns exactly the op- + tions that were passed to pcre2_compile(), whereas PCRE2_INFO_ALLOP- + TIONS returns the compile options as modified by any top-level (*XXX) + option settings such as (*UTF) at the start of the pattern itself. + PCRE2_INFO_EXTRAOPTIONS returns the extra options that were set in the + compile context by calling the pcre2_set_compile_extra_options() func- tion. - For example, if the pattern /(*UTF)abc/ is compiled with the PCRE2_EX- - TENDED option, the result for PCRE2_INFO_ALLOPTIONS is PCRE2_EXTENDED - and PCRE2_UTF. Option settings such as (?i) that can change within a + For example, if the pattern /(*UTF)abc/ is compiled with the PCRE2_EX- + TENDED option, the result for PCRE2_INFO_ALLOPTIONS is PCRE2_EXTENDED + and PCRE2_UTF. Option settings such as (?i) that can change within a pattern do not affect the result of PCRE2_INFO_ALLOPTIONS, even if they - appear right at the start of the pattern. (This was different in some + appear right at the start of the pattern. (This was different in some earlier releases.) - A pattern compiled without PCRE2_ANCHORED is automatically anchored by + A pattern compiled without PCRE2_ANCHORED is automatically anchored by PCRE2 if the first significant item in every top-level branch is one of the following: @@ -2103,7 +2148,7 @@ INFORMATION ABOUT A COMPILED PATTERN \G always .* sometimes - see below - When .* is the first significant item, anchoring is possible only when + When .* is the first significant item, anchoring is possible only when all the following are true: .* is not in an atomic group @@ -2113,94 +2158,94 @@ INFORMATION ABOUT A COMPILED PATTERN Neither (*PRUNE) nor (*SKIP) appears in the pattern PCRE2_NO_DOTSTAR_ANCHOR is not set - For patterns that are auto-anchored, the PCRE2_ANCHORED bit is set in + For patterns that are auto-anchored, the PCRE2_ANCHORED bit is set in the options returned for PCRE2_INFO_ALLOPTIONS. PCRE2_INFO_BACKREFMAX - Return the number of the highest backreference in the pattern. The - third argument should point to a uint32_t variable. Named capture - groups acquire numbers as well as names, and these count towards the - highest backreference. Backreferences such as \4 or \g{12} match the + Return the number of the highest backreference in the pattern. The + third argument should point to a uint32_t variable. Named capture + groups acquire numbers as well as names, and these count towards the + highest backreference. Backreferences such as \4 or \g{12} match the captured characters of the given group, but in addition, the check that a capture group is set in a conditional group such as (?(3)a|b) is also a backreference. Zero is returned if there are no backreferences. PCRE2_INFO_BSR - The output is a uint32_t integer whose value indicates what character - sequences the \R escape sequence matches. A value of PCRE2_BSR_UNICODE - means that \R matches any Unicode line ending sequence; a value of + The output is a uint32_t integer whose value indicates what character + sequences the \R escape sequence matches. A value of PCRE2_BSR_UNICODE + means that \R matches any Unicode line ending sequence; a value of PCRE2_BSR_ANYCRLF means that \R matches only CR, LF, or CRLF. PCRE2_INFO_CAPTURECOUNT - Return the highest capture group number in the pattern. In patterns + Return the highest capture group number in the pattern. In patterns where (?| is not used, this is also the total number of capture groups. The third argument should point to a uint32_t variable. PCRE2_INFO_DEPTHLIMIT - If the pattern set a backtracking depth limit by including an item of - the form (*LIMIT_DEPTH=nnnn) at the start, the value is returned. The + If the pattern set a backtracking depth limit by including an item of + the form (*LIMIT_DEPTH=nnnn) at the start, the value is returned. The third argument should point to a uint32_t integer. If no such value has - been set, the call to pcre2_pattern_info() returns the error PCRE2_ER- + been set, the call to pcre2_pattern_info() returns the error PCRE2_ER- ROR_UNSET. Note that this limit will only be used during matching if it - is less than the limit set or defaulted by the caller of the match + is less than the limit set or defaulted by the caller of the match function. PCRE2_INFO_FIRSTBITMAP - In the absence of a single first code unit for a non-anchored pattern, - pcre2_compile() may construct a 256-bit table that defines a fixed set - of values for the first code unit in any match. For example, a pattern - that starts with [abc] results in a table with three bits set. When - code unit values greater than 255 are supported, the flag bit for 255 - means "any code unit of value 255 or above". If such a table was con- - structed, a pointer to it is returned. Otherwise NULL is returned. The + In the absence of a single first code unit for a non-anchored pattern, + pcre2_compile() may construct a 256-bit table that defines a fixed set + of values for the first code unit in any match. For example, a pattern + that starts with [abc] results in a table with three bits set. When + code unit values greater than 255 are supported, the flag bit for 255 + means "any code unit of value 255 or above". If such a table was con- + structed, a pointer to it is returned. Otherwise NULL is returned. The third argument should point to a const uint8_t * variable. PCRE2_INFO_FIRSTCODETYPE Return information about the first code unit of any matched string, for - a non-anchored pattern. The third argument should point to a uint32_t - variable. If there is a fixed first value, for example, the letter "c" - from a pattern such as (cat|cow|coyote), 1 is returned, and the value - can be retrieved using PCRE2_INFO_FIRSTCODEUNIT. If there is no fixed - first value, but it is known that a match can occur only at the start - of the subject or following a newline in the subject, 2 is returned. + a non-anchored pattern. The third argument should point to a uint32_t + variable. If there is a fixed first value, for example, the letter "c" + from a pattern such as (cat|cow|coyote), 1 is returned, and the value + can be retrieved using PCRE2_INFO_FIRSTCODEUNIT. If there is no fixed + first value, but it is known that a match can occur only at the start + of the subject or following a newline in the subject, 2 is returned. Otherwise, and for anchored patterns, 0 is returned. PCRE2_INFO_FIRSTCODEUNIT - Return the value of the first code unit of any matched string for a - pattern where PCRE2_INFO_FIRSTCODETYPE returns 1; otherwise return 0. - The third argument should point to a uint32_t variable. In the 8-bit - library, the value is always less than 256. In the 16-bit library the - value can be up to 0xffff. In the 32-bit library in UTF-32 mode the + Return the value of the first code unit of any matched string for a + pattern where PCRE2_INFO_FIRSTCODETYPE returns 1; otherwise return 0. + The third argument should point to a uint32_t variable. In the 8-bit + library, the value is always less than 256. In the 16-bit library the + value can be up to 0xffff. In the 32-bit library in UTF-32 mode the value can be up to 0x10ffff, and up to 0xffffffff when not using UTF-32 mode. PCRE2_INFO_FRAMESIZE Return the size (in bytes) of the data frames that are used to remember - backtracking positions when the pattern is processed by pcre2_match() - without the use of JIT. The third argument should point to a size_t + backtracking positions when the pattern is processed by pcre2_match() + without the use of JIT. The third argument should point to a size_t variable. The frame size depends on the number of capturing parentheses in the pattern. Each additional capture group adds two PCRE2_SIZE vari- ables. PCRE2_INFO_HASBACKSLASHC - Return 1 if the pattern contains any instances of \C, otherwise 0. The + Return 1 if the pattern contains any instances of \C, otherwise 0. The third argument should point to a uint32_t variable. PCRE2_INFO_HASCRORLF - Return 1 if the pattern contains any explicit matches for CR or LF - characters, otherwise 0. The third argument should point to a uint32_t - variable. An explicit match is either a literal CR or LF character, or - \r or \n or one of the equivalent hexadecimal or octal escape se- + Return 1 if the pattern contains any explicit matches for CR or LF + characters, otherwise 0. The third argument should point to a uint32_t + variable. An explicit match is either a literal CR or LF character, or + \r or \n or one of the equivalent hexadecimal or octal escape se- quences. PCRE2_INFO_HEAPLIMIT @@ -2208,45 +2253,45 @@ INFORMATION ABOUT A COMPILED PATTERN If the pattern set a heap memory limit by including an item of the form (*LIMIT_HEAP=nnnn) at the start, the value is returned. The third argu- ment should point to a uint32_t integer. If no such value has been set, - the call to pcre2_pattern_info() returns the error PCRE2_ERROR_UNSET. - Note that this limit will only be used during matching if it is less + the call to pcre2_pattern_info() returns the error PCRE2_ERROR_UNSET. + Note that this limit will only be used during matching if it is less than the limit set or defaulted by the caller of the match function. PCRE2_INFO_JCHANGED - Return 1 if the (?J) or (?-J) option setting is used in the pattern, - otherwise 0. The third argument should point to a uint32_t variable. - (?J) and (?-J) set and unset the local PCRE2_DUPNAMES option, respec- + Return 1 if the (?J) or (?-J) option setting is used in the pattern, + otherwise 0. The third argument should point to a uint32_t variable. + (?J) and (?-J) set and unset the local PCRE2_DUPNAMES option, respec- tively. PCRE2_INFO_JITSIZE - If the compiled pattern was successfully processed by pcre2_jit_com- - pile(), return the size of the JIT compiled code, otherwise return + If the compiled pattern was successfully processed by pcre2_jit_com- + pile(), return the size of the JIT compiled code, otherwise return zero. The third argument should point to a size_t variable. PCRE2_INFO_LASTCODETYPE - Returns 1 if there is a rightmost literal code unit that must exist in - any matched string, other than at its start. The third argument should + Returns 1 if there is a rightmost literal code unit that must exist in + any matched string, other than at its start. The third argument should point to a uint32_t variable. If there is no such value, 0 is returned. - When 1 is returned, the code unit value itself can be retrieved using + When 1 is returned, the code unit value itself can be retrieved using PCRE2_INFO_LASTCODEUNIT. For anchored patterns, a last literal value is - recorded only if it follows something of variable length. For example, - for the pattern /^a\d+z\d+/ the returned value is 1 (with "z" returned - from PCRE2_INFO_LASTCODEUNIT), but for /^a\dz\d/ the returned value is + recorded only if it follows something of variable length. For example, + for the pattern /^a\d+z\d+/ the returned value is 1 (with "z" returned + from PCRE2_INFO_LASTCODEUNIT), but for /^a\dz\d/ the returned value is 0. PCRE2_INFO_LASTCODEUNIT - Return the value of the rightmost literal code unit that must exist in - any matched string, other than at its start, for a pattern where + Return the value of the rightmost literal code unit that must exist in + any matched string, other than at its start, for a pattern where PCRE2_INFO_LASTCODETYPE returns 1. Otherwise, return 0. The third argu- ment should point to a uint32_t variable. PCRE2_INFO_MATCHEMPTY - Return 1 if the pattern might match an empty string, otherwise 0. The + Return 1 if the pattern might match an empty string, otherwise 0. The third argument should point to a uint32_t variable. When a pattern con- tains recursive subroutine calls it is not always possible to determine whether or not it can match an empty string. PCRE2 takes a cautious ap- @@ -2254,44 +2299,44 @@ INFORMATION ABOUT A COMPILED PATTERN PCRE2_INFO_MATCHLIMIT - If the pattern set a match limit by including an item of the form - (*LIMIT_MATCH=nnnn) at the start, the value is returned. The third ar- - gument should point to a uint32_t integer. If no such value has been + If the pattern set a match limit by including an item of the form + (*LIMIT_MATCH=nnnn) at the start, the value is returned. The third ar- + gument should point to a uint32_t integer. If no such value has been set, the call to pcre2_pattern_info() returns the error PCRE2_ERROR_UN- - SET. Note that this limit will only be used during matching if it is - less than the limit set or defaulted by the caller of the match func- + SET. Note that this limit will only be used during matching if it is + less than the limit set or defaulted by the caller of the match func- tion. PCRE2_INFO_MAXLOOKBEHIND - A lookbehind assertion moves back a certain number of characters (not - code units) when it starts to process each of its branches. This re- - quest returns the largest of these backward moves. The third argument + A lookbehind assertion moves back a certain number of characters (not + code units) when it starts to process each of its branches. This re- + quest returns the largest of these backward moves. The third argument should point to a uint32_t integer. The simple assertions \b and \B re- - quire a one-character lookbehind and cause PCRE2_INFO_MAXLOOKBEHIND to - return 1 in the absence of anything longer. \A also registers a one- - character lookbehind, though it does not actually inspect the previous + quire a one-character lookbehind and cause PCRE2_INFO_MAXLOOKBEHIND to + return 1 in the absence of anything longer. \A also registers a one- + character lookbehind, though it does not actually inspect the previous character. Note that this information is useful for multi-segment matching only if - the pattern contains no nested lookbehinds. For example, the pattern - (?<=a(?<=ba)c) returns a maximum lookbehind of 2, but when it is pro- - cessed, the first lookbehind moves back by two characters, matches one - character, then the nested lookbehind also moves back by two charac- + the pattern contains no nested lookbehinds. For example, the pattern + (?<=a(?<=ba)c) returns a maximum lookbehind of 2, but when it is pro- + cessed, the first lookbehind moves back by two characters, matches one + character, then the nested lookbehind also moves back by two charac- ters. This puts the matching point three characters earlier than it was - at the start. PCRE2_INFO_MAXLOOKBEHIND is really only useful as a de- - bugging tool. See the pcre2partial documentation for a discussion of + at the start. PCRE2_INFO_MAXLOOKBEHIND is really only useful as a de- + bugging tool. See the pcre2partial documentation for a discussion of multi-segment matching. PCRE2_INFO_MINLENGTH - If a minimum length for matching subject strings was computed, its + If a minimum length for matching subject strings was computed, its value is returned. Otherwise the returned value is 0. This value is not - computed when PCRE2_NO_START_OPTIMIZE is set. The value is a number of - characters, which in UTF mode may be different from the number of code - units. The third argument should point to a uint32_t variable. The - value is a lower bound to the length of any matching string. There may - not be any strings of that length that do actually match, but every + computed when PCRE2_NO_START_OPTIMIZE is set. The value is a number of + characters, which in UTF mode may be different from the number of code + units. The third argument should point to a uint32_t variable. The + value is a lower bound to the length of any matching string. There may + not be any strings of that length that do actually match, but every string that does match is at least that long. PCRE2_INFO_NAMECOUNT @@ -2299,51 +2344,51 @@ INFORMATION ABOUT A COMPILED PATTERN PCRE2_INFO_NAMETABLE PCRE2 supports the use of named as well as numbered capturing parenthe- - ses. The names are just an additional way of identifying the parenthe- + ses. The names are just an additional way of identifying the parenthe- ses, which still acquire numbers. Several convenience functions such as - pcre2_substring_get_byname() are provided for extracting captured sub- - strings by name. It is also possible to extract the data directly, by - first converting the name to a number in order to access the correct - pointers in the output vector (described with pcre2_match() below). To + pcre2_substring_get_byname() are provided for extracting captured sub- + strings by name. It is also possible to extract the data directly, by + first converting the name to a number in order to access the correct + pointers in the output vector (described with pcre2_match() below). To do the conversion, you need to use the name-to-number map, which is de- scribed by these three values. - The map consists of a number of fixed-size entries. PCRE2_INFO_NAME- - COUNT gives the number of entries, and PCRE2_INFO_NAMEENTRYSIZE gives - the size of each entry in code units; both of these return a uint32_t + The map consists of a number of fixed-size entries. PCRE2_INFO_NAME- + COUNT gives the number of entries, and PCRE2_INFO_NAMEENTRYSIZE gives + the size of each entry in code units; both of these return a uint32_t value. The entry size depends on the length of the longest name. PCRE2_INFO_NAMETABLE returns a pointer to the first entry of the table. This is a PCRE2_SPTR pointer to a block of code units. In the 8-bit li- - brary, the first two bytes of each entry are the number of the captur- - ing parenthesis, most significant byte first. In the 16-bit library, - the pointer points to 16-bit code units, the first of which contains - the parenthesis number. In the 32-bit library, the pointer points to - 32-bit code units, the first of which contains the parenthesis number. + brary, the first two bytes of each entry are the number of the captur- + ing parenthesis, most significant byte first. In the 16-bit library, + the pointer points to 16-bit code units, the first of which contains + the parenthesis number. In the 32-bit library, the pointer points to + 32-bit code units, the first of which contains the parenthesis number. The rest of the entry is the corresponding name, zero terminated. - The names are in alphabetical order. If (?| is used to create multiple + The names are in alphabetical order. If (?| is used to create multiple capture groups with the same number, as described in the section on du- plicate group numbers in the pcre2pattern page, the groups may be given - the same name, but there is only one entry in the table. Different + the same name, but there is only one entry in the table. Different names for groups of the same number are not permitted. - Duplicate names for capture groups with different numbers are permit- + Duplicate names for capture groups with different numbers are permit- ted, but only if PCRE2_DUPNAMES is set. They appear in the table in the - order in which they were found in the pattern. In the absence of (?| - this is the order of increasing number; when (?| is used this is not - necessarily the case because later capture groups may have lower num- + order in which they were found in the pattern. In the absence of (?| + this is the order of increasing number; when (?| is used this is not + necessarily the case because later capture groups may have lower num- bers. - As a simple example of the name/number table, consider the following - pattern after compilation by the 8-bit library (assume PCRE2_EXTENDED + As a simple example of the name/number table, consider the following + pattern after compilation by the 8-bit library (assume PCRE2_EXTENDED is set, so white space - including newlines - is ignored): (?
(? (\d\d)?\d\d) - (? \d\d) - (? \d\d) ) There are four named capture groups, so the table has four entries, and - each entry in the table is eight bytes long. The table is as follows, + each entry in the table is eight bytes long. The table is as follows, with non-printing bytes shows in hexadecimal, and undefined bytes shown as ??: @@ -2352,8 +2397,8 @@ INFORMATION ABOUT A COMPILED PATTERN 00 04 m o n t h 00 00 02 y e a r 00 ?? - When writing code to extract data from named capture groups using the - name-to-number map, remember that the length of the entries is likely + When writing code to extract data from named capture groups using the + name-to-number map, remember that the length of the entries is likely to be different for each compiled pattern. PCRE2_INFO_NEWLINE @@ -2372,14 +2417,14 @@ INFORMATION ABOUT A COMPILED PATTERN PCRE2_INFO_SIZE - Return the size of the compiled pattern in bytes (for all three li- - braries). The third argument should point to a size_t variable. This - value includes the size of the general data block that precedes the - code units of the compiled pattern itself. The value that is used when - pcre2_compile() is getting memory in which to place the compiled pat- + Return the size of the compiled pattern in bytes (for all three li- + braries). The third argument should point to a size_t variable. This + value includes the size of the general data block that precedes the + code units of the compiled pattern itself. The value that is used when + pcre2_compile() is getting memory in which to place the compiled pat- tern may be slightly larger than the value returned by this option, be- - cause there are cases where the code that calculates the size has to - over-estimate. Processing a pattern with the JIT compiler does not al- + cause there are cases where the code that calculates the size has to + over-estimate. Processing a pattern with the JIT compiler does not al- ter the value returned by this option. @@ -2390,30 +2435,30 @@ INFORMATION ABOUT A PATTERN'S CALLOUTS void *user_data); A script language that supports the use of string arguments in callouts - might like to scan all the callouts in a pattern before running the + might like to scan all the callouts in a pattern before running the match. This can be done by calling pcre2_callout_enumerate(). The first - argument is a pointer to a compiled pattern, the second points to a - callback function, and the third is arbitrary user data. The callback - function is called for every callout in the pattern in the order in + argument is a pointer to a compiled pattern, the second points to a + callback function, and the third is arbitrary user data. The callback + function is called for every callout in the pattern in the order in which they appear. Its first argument is a pointer to a callout enumer- - ation block, and its second argument is the user_data value that was - passed to pcre2_callout_enumerate(). The contents of the callout enu- - meration block are described in the pcre2callout documentation, which + ation block, and its second argument is the user_data value that was + passed to pcre2_callout_enumerate(). The contents of the callout enu- + meration block are described in the pcre2callout documentation, which also gives further details about callouts. SERIALIZATION AND PRECOMPILING - It is possible to save compiled patterns on disc or elsewhere, and - reload them later, subject to a number of restrictions. The host on - which the patterns are reloaded must be running the same version of + It is possible to save compiled patterns on disc or elsewhere, and + reload them later, subject to a number of restrictions. The host on + which the patterns are reloaded must be running the same version of PCRE2, with the same code unit width, and must also have the same endi- - anness, pointer width, and PCRE2_SIZE type. Before compiled patterns - can be saved, they must be converted to a "serialized" form, which in - the case of PCRE2 is really just a bytecode dump. The functions whose - names begin with pcre2_serialize_ are used for converting to and from - the serialized form. They are described in the pcre2serialize documen- - tation. Note that PCRE2 serialization does not convert compiled pat- + anness, pointer width, and PCRE2_SIZE type. Before compiled patterns + can be saved, they must be converted to a "serialized" form, which in + the case of PCRE2 is really just a bytecode dump. The functions whose + names begin with pcre2_serialize_ are used for converting to and from + the serialized form. They are described in the pcre2serialize documen- + tation. Note that PCRE2 serialization does not convert compiled pat- terns to an abstract format like Java or .NET serialization. @@ -2427,58 +2472,68 @@ THE MATCH DATA BLOCK void pcre2_match_data_free(pcre2_match_data *match_data); - Information about a successful or unsuccessful match is placed in a - match data block, which is an opaque structure that is accessed by - function calls. In particular, the match data block contains a vector - of offsets into the subject string that define the matched part of the - subject and any substrings that were captured. This is known as the - ovector. + Information about a successful or unsuccessful match is placed in a + match data block, which is an opaque structure that is accessed by + function calls. In particular, the match data block contains a vector + of offsets into the subject string that define the matched parts of the + subject. This is known as the ovector. Before calling pcre2_match(), pcre2_dfa_match(), or pcre2_jit_match() you must create a match data block by calling one of the creation func- tions above. For pcre2_match_data_create(), the first argument is the - number of pairs of offsets in the ovector. One pair of offsets is re- - quired to identify the string that matched the whole pattern, with an - additional pair for each captured substring. For example, a value of 4 - creates enough space to record the matched portion of the subject plus - three captured substrings. A minimum of at least 1 pair is imposed by - pcre2_match_data_create(), so it is always possible to return the over- - all matched string. + number of pairs of offsets in the ovector. + + When using pcre2_match(), one pair of offsets is required to identify + the string that matched the whole pattern, with an additional pair for + each captured substring. For example, a value of 4 creates enough space + to record the matched portion of the subject plus three captured sub- + strings. + + When using pcre2_dfa_match() there may be multiple matched substrings + of different lengths at the same point in the subject. The ovector + should be made large enough to hold as many as are expected. + + A minimum of at least 1 pair is imposed by pcre2_match_data_create(), + so it is always possible to return the overall matched string in the + case of pcre2_match() or the longest match in the case of + pcre2_dfa_match(). The second argument of pcre2_match_data_create() is a pointer to a gen- - eral context, which can specify custom memory management for obtaining + eral context, which can specify custom memory management for obtaining the memory for the match data block. If you are not using custom memory management, pass NULL, which causes malloc() to be used. - For pcre2_match_data_create_from_pattern(), the first argument is a + For pcre2_match_data_create_from_pattern(), the first argument is a pointer to a compiled pattern. The ovector is created to be exactly the - right size to hold all the substrings a pattern might capture. The sec- - ond argument is again a pointer to a general context, but in this case - if NULL is passed, the memory is obtained using the same allocator that - was used for the compiled pattern (custom or default). - - A match data block can be used many times, with the same or different - compiled patterns. You can extract information from a match data block - after a match operation has finished, using functions that are de- + right size to hold all the substrings a pattern might capture when + matched using pcre2_match(). You should not use this call when matching + with pcre2_dfa_match(). The second argument is again a pointer to a + general context, but in this case if NULL is passed, the memory is ob- + tained using the same allocator that was used for the compiled pattern + (custom or default). + + A match data block can be used many times, with the same or different + compiled patterns. You can extract information from a match data block + after a match operation has finished, using functions that are de- scribed in the sections on matched strings and other match data below. - When a call of pcre2_match() fails, valid data is available in the - match block only when the error is PCRE2_ERROR_NOMATCH, PCRE2_ER- - ROR_PARTIAL, or one of the error codes for an invalid UTF string. Ex- + When a call of pcre2_match() fails, valid data is available in the + match block only when the error is PCRE2_ERROR_NOMATCH, PCRE2_ER- + ROR_PARTIAL, or one of the error codes for an invalid UTF string. Ex- actly what is available depends on the error, and is detailed below. - When one of the matching functions is called, pointers to the compiled - pattern and the subject string are set in the match data block so that - they can be referenced by the extraction functions after a successful + When one of the matching functions is called, pointers to the compiled + pattern and the subject string are set in the match data block so that + they can be referenced by the extraction functions after a successful match. After running a match, you must not free a compiled pattern or a - subject string until after all operations on the match data block (for - that match) have taken place, unless, in the case of the subject - string, you have used the PCRE2_COPY_MATCHED_SUBJECT option, which is - described in the section entitled "Option bits for pcre2_match()" be- + subject string until after all operations on the match data block (for + that match) have taken place, unless, in the case of the subject + string, you have used the PCRE2_COPY_MATCHED_SUBJECT option, which is + described in the section entitled "Option bits for pcre2_match()" be- low. - When a match data block itself is no longer needed, it should be freed - by calling pcre2_match_data_free(). If this function is called with a + When a match data block itself is no longer needed, it should be freed + by calling pcre2_match_data_free(). If this function is called with a NULL argument, it returns immediately, without doing anything. @@ -2489,15 +2544,15 @@ MATCHING A PATTERN: THE TRADITIONAL FUNCTION uint32_t options, pcre2_match_data *match_data, pcre2_match_context *mcontext); - The function pcre2_match() is called to match a subject string against - a compiled pattern, which is passed in the code argument. You can call + The function pcre2_match() is called to match a subject string against + a compiled pattern, which is passed in the code argument. You can call pcre2_match() with the same code argument as many times as you like, in - order to find multiple matches in the subject string or to match dif- + order to find multiple matches in the subject string or to match dif- ferent subject strings with the same pattern. - This function is the main matching facility of the library, and it op- - erates in a Perl-like manner. For specialist use there is also an al- - ternative matching function, which is described below in the section + This function is the main matching facility of the library, and it op- + erates in a Perl-like manner. For specialist use there is also an al- + ternative matching function, which is described below in the section about the pcre2_dfa_match() function. Here is an example of a simple call to pcre2_match(): @@ -2512,215 +2567,215 @@ MATCHING A PATTERN: THE TRADITIONAL FUNCTION md, /* the match data block */ NULL); /* a match context; NULL means use defaults */ - If the subject string is zero-terminated, the length can be given as + If the subject string is zero-terminated, the length can be given as PCRE2_ZERO_TERMINATED. A match context must be provided if certain less common matching parameters are to be changed. For details, see the sec- tion on the match context above. The string to be matched by pcre2_match() - The subject string is passed to pcre2_match() as a pointer in subject, - a length in length, and a starting offset in startoffset. The length - and offset are in code units, not characters. That is, they are in - bytes for the 8-bit library, 16-bit code units for the 16-bit library, - and 32-bit code units for the 32-bit library, whether or not UTF pro- + The subject string is passed to pcre2_match() as a pointer in subject, + a length in length, and a starting offset in startoffset. The length + and offset are in code units, not characters. That is, they are in + bytes for the 8-bit library, 16-bit code units for the 16-bit library, + and 32-bit code units for the 32-bit library, whether or not UTF pro- cessing is enabled. If startoffset is greater than the length of the subject, pcre2_match() - returns PCRE2_ERROR_BADOFFSET. When the starting offset is zero, the - search for a match starts at the beginning of the subject, and this is + returns PCRE2_ERROR_BADOFFSET. When the starting offset is zero, the + search for a match starts at the beginning of the subject, and this is by far the most common case. In UTF-8 or UTF-16 mode, the starting off- - set must point to the start of a character, or to the end of the sub- - ject (in UTF-32 mode, one code unit equals one character, so all off- - sets are valid). Like the pattern string, the subject may contain bi- + set must point to the start of a character, or to the end of the sub- + ject (in UTF-32 mode, one code unit equals one character, so all off- + sets are valid). Like the pattern string, the subject may contain bi- nary zeros. - A non-zero starting offset is useful when searching for another match - in the same subject by calling pcre2_match() again after a previous - success. Setting startoffset differs from passing over a shortened - string and setting PCRE2_NOTBOL in the case of a pattern that begins + A non-zero starting offset is useful when searching for another match + in the same subject by calling pcre2_match() again after a previous + success. Setting startoffset differs from passing over a shortened + string and setting PCRE2_NOTBOL in the case of a pattern that begins with any kind of lookbehind. For example, consider the pattern \Biss\B - which finds occurrences of "iss" in the middle of words. (\B matches - only if the current position in the subject is not a word boundary.) - When applied to the string "Mississipi" the first call to pcre2_match() - finds the first occurrence. If pcre2_match() is called again with just - the remainder of the subject, namely "issipi", it does not match, be- - cause \B is always false at the start of the subject, which is deemed - to be a word boundary. However, if pcre2_match() is passed the entire - string again, but with startoffset set to 4, it finds the second occur- - rence of "iss" because it is able to look behind the starting point to - discover that it is preceded by a letter. - - Finding all the matches in a subject is tricky when the pattern can + which finds occurrences of "iss" in the middle of words. (\B matches + only if the current position in the subject is not a word boundary.) + When applied to the string "Mississippi" the first call to + pcre2_match() finds the first occurrence. If pcre2_match() is called + again with just the remainder of the subject, namely "issippi", it does + not match, because \B is always false at the start of the subject, + which is deemed to be a word boundary. However, if pcre2_match() is + passed the entire string again, but with startoffset set to 4, it finds + the second occurrence of "iss" because it is able to look behind the + starting point to discover that it is preceded by a letter. + + Finding all the matches in a subject is tricky when the pattern can match an empty string. It is possible to emulate Perl's /g behaviour by - first trying the match again at the same offset, with the - PCRE2_NOTEMPTY_ATSTART and PCRE2_ANCHORED options, and then if that - fails, advancing the starting offset and trying an ordinary match - again. There is some code that demonstrates how to do this in the - pcre2demo sample program. In the most general case, you have to check - to see if the newline convention recognizes CRLF as a newline, and if - so, and the current character is CR followed by LF, advance the start- + first trying the match again at the same offset, with the + PCRE2_NOTEMPTY_ATSTART and PCRE2_ANCHORED options, and then if that + fails, advancing the starting offset and trying an ordinary match + again. There is some code that demonstrates how to do this in the + pcre2demo sample program. In the most general case, you have to check + to see if the newline convention recognizes CRLF as a newline, and if + so, and the current character is CR followed by LF, advance the start- ing offset by two characters instead of one. If a non-zero starting offset is passed when the pattern is anchored, a single attempt to match at the given offset is made. This can only suc- - ceed if the pattern does not require the match to be at the start of - the subject. In other words, the anchoring must be the result of set- - ting the PCRE2_ANCHORED option or the use of .* with PCRE2_DOTALL, not + ceed if the pattern does not require the match to be at the start of + the subject. In other words, the anchoring must be the result of set- + ting the PCRE2_ANCHORED option or the use of .* with PCRE2_DOTALL, not by starting the pattern with ^ or \A. Option bits for pcre2_match() The unused bits of the options argument for pcre2_match() must be zero. - The only bits that may be set are PCRE2_ANCHORED, - PCRE2_COPY_MATCHED_SUBJECT, PCRE2_ENDANCHORED, PCRE2_NOTBOL, PCRE2_NO- + The only bits that may be set are PCRE2_ANCHORED, + PCRE2_COPY_MATCHED_SUBJECT, PCRE2_ENDANCHORED, PCRE2_NOTBOL, PCRE2_NO- TEOL, PCRE2_NOTEMPTY, PCRE2_NOTEMPTY_ATSTART, PCRE2_NO_JIT, - PCRE2_NO_UTF_CHECK, PCRE2_PARTIAL_HARD, and PCRE2_PARTIAL_SOFT. Their + PCRE2_NO_UTF_CHECK, PCRE2_PARTIAL_HARD, and PCRE2_PARTIAL_SOFT. Their action is described below. - Setting PCRE2_ANCHORED or PCRE2_ENDANCHORED at match time is not sup- - ported by the just-in-time (JIT) compiler. If it is set, JIT matching - is disabled and the interpretive code in pcre2_match() is run. Apart - from PCRE2_NO_JIT (obviously), the remaining options are supported for + Setting PCRE2_ANCHORED or PCRE2_ENDANCHORED at match time is not sup- + ported by the just-in-time (JIT) compiler. If it is set, JIT matching + is disabled and the interpretive code in pcre2_match() is run. Apart + from PCRE2_NO_JIT (obviously), the remaining options are supported for JIT matching. PCRE2_ANCHORED The PCRE2_ANCHORED option limits pcre2_match() to matching at the first - matching position. If a pattern was compiled with PCRE2_ANCHORED, or - turned out to be anchored by virtue of its contents, it cannot be made - unachored at matching time. Note that setting the option at match time + matching position. If a pattern was compiled with PCRE2_ANCHORED, or + turned out to be anchored by virtue of its contents, it cannot be made + unachored at matching time. Note that setting the option at match time disables JIT matching. PCRE2_COPY_MATCHED_SUBJECT - By default, a pointer to the subject is remembered in the match data - block so that, after a successful match, it can be referenced by the - substring extraction functions. This means that the subject's memory - must not be freed until all such operations are complete. For some ap- - plications where the lifetime of the subject string is not guaranteed, - it may be necessary to make a copy of the subject string, but it is - wasteful to do this unless the match is successful. After a successful - match, if PCRE2_COPY_MATCHED_SUBJECT is set, the subject is copied and - the new pointer is remembered in the match data block instead of the - original subject pointer. The memory allocator that was used for the - match block itself is used. The copy is automatically freed when - pcre2_match_data_free() is called to free the match data block. It is + By default, a pointer to the subject is remembered in the match data + block so that, after a successful match, it can be referenced by the + substring extraction functions. This means that the subject's memory + must not be freed until all such operations are complete. For some ap- + plications where the lifetime of the subject string is not guaranteed, + it may be necessary to make a copy of the subject string, but it is + wasteful to do this unless the match is successful. After a successful + match, if PCRE2_COPY_MATCHED_SUBJECT is set, the subject is copied and + the new pointer is remembered in the match data block instead of the + original subject pointer. The memory allocator that was used for the + match block itself is used. The copy is automatically freed when + pcre2_match_data_free() is called to free the match data block. It is also automatically freed if the match data block is re-used for another match operation. PCRE2_ENDANCHORED - If the PCRE2_ENDANCHORED option is set, any string that pcre2_match() - matches must be right at the end of the subject string. Note that set- + If the PCRE2_ENDANCHORED option is set, any string that pcre2_match() + matches must be right at the end of the subject string. Note that set- ting the option at match time disables JIT matching. PCRE2_NOTBOL This option specifies that first character of the subject string is not - the beginning of a line, so the circumflex metacharacter should not - match before it. Setting this without having set PCRE2_MULTILINE at + the beginning of a line, so the circumflex metacharacter should not + match before it. Setting this without having set PCRE2_MULTILINE at compile time causes circumflex never to match. This option affects only the behaviour of the circumflex metacharacter. It does not affect \A. PCRE2_NOTEOL This option specifies that the end of the subject string is not the end - of a line, so the dollar metacharacter should not match it nor (except - in multiline mode) a newline immediately before it. Setting this with- - out having set PCRE2_MULTILINE at compile time causes dollar never to + of a line, so the dollar metacharacter should not match it nor (except + in multiline mode) a newline immediately before it. Setting this with- + out having set PCRE2_MULTILINE at compile time causes dollar never to match. This option affects only the behaviour of the dollar metacharac- ter. It does not affect \Z or \z. PCRE2_NOTEMPTY An empty string is not considered to be a valid match if this option is - set. If there are alternatives in the pattern, they are tried. If all - the alternatives match the empty string, the entire match fails. For + set. If there are alternatives in the pattern, they are tried. If all + the alternatives match the empty string, the entire match fails. For example, if the pattern a?b? - is applied to a string not beginning with "a" or "b", it matches an + is applied to a string not beginning with "a" or "b", it matches an empty string at the start of the subject. With PCRE2_NOTEMPTY set, this - match is not valid, so pcre2_match() searches further into the string + match is not valid, so pcre2_match() searches further into the string for occurrences of "a" or "b". PCRE2_NOTEMPTY_ATSTART - This is like PCRE2_NOTEMPTY, except that it locks out an empty string + This is like PCRE2_NOTEMPTY, except that it locks out an empty string match only at the first matching position, that is, at the start of the - subject plus the starting offset. An empty string match later in the + subject plus the starting offset. An empty string match later in the subject is permitted. If the pattern is anchored, such a match can oc- cur only if the pattern contains \K. PCRE2_NO_JIT - By default, if a pattern has been successfully processed by - pcre2_jit_compile(), JIT is automatically used when pcre2_match() is - called with options that JIT supports. Setting PCRE2_NO_JIT disables + By default, if a pattern has been successfully processed by + pcre2_jit_compile(), JIT is automatically used when pcre2_match() is + called with options that JIT supports. Setting PCRE2_NO_JIT disables the use of JIT; it forces matching to be done by the interpreter. PCRE2_NO_UTF_CHECK When PCRE2_UTF is set at compile time, the validity of the subject as a - UTF string is checked unless PCRE2_NO_UTF_CHECK is passed to + UTF string is checked unless PCRE2_NO_UTF_CHECK is passed to pcre2_match() or PCRE2_MATCH_INVALID_UTF was passed to pcre2_compile(). The latter special case is discussed in detail in the pcre2unicode doc- umentation. - In the default case, if a non-zero starting offset is given, the check - is applied only to that part of the subject that could be inspected - during matching, and there is a check that the starting offset points - to the first code unit of a character or to the end of the subject. If - there are no lookbehind assertions in the pattern, the check starts at + In the default case, if a non-zero starting offset is given, the check + is applied only to that part of the subject that could be inspected + during matching, and there is a check that the starting offset points + to the first code unit of a character or to the end of the subject. If + there are no lookbehind assertions in the pattern, the check starts at the starting offset. Otherwise, it starts at the length of the longest - lookbehind before the starting offset, or at the start of the subject - if there are not that many characters before the starting offset. Note + lookbehind before the starting offset, or at the start of the subject + if there are not that many characters before the starting offset. Note that the sequences \b and \B are one-character lookbehinds. The check is carried out before any other processing takes place, and a - negative error code is returned if the check fails. There are several - UTF error codes for each code unit width, corresponding to different - problems with the code unit sequence. There are discussions about the - validity of UTF-8 strings, UTF-16 strings, and UTF-32 strings in the + negative error code is returned if the check fails. There are several + UTF error codes for each code unit width, corresponding to different + problems with the code unit sequence. There are discussions about the + validity of UTF-8 strings, UTF-16 strings, and UTF-32 strings in the pcre2unicode documentation. If you know that your subject is valid, and you want to skip this check for performance reasons, you can set the PCRE2_NO_UTF_CHECK option when - calling pcre2_match(). You might want to do this for the second and - subsequent calls to pcre2_match() if you are making repeated calls to + calling pcre2_match(). You might want to do this for the second and + subsequent calls to pcre2_match() if you are making repeated calls to find multiple matches in the same subject string. - Warning: Unless PCRE2_MATCH_INVALID_UTF was set at compile time, when - PCRE2_NO_UTF_CHECK is set at match time the effect of passing an in- + Warning: Unless PCRE2_MATCH_INVALID_UTF was set at compile time, when + PCRE2_NO_UTF_CHECK is set at match time the effect of passing an in- valid string as a subject, or an invalid value of startoffset, is unde- - fined. Your program may crash or loop indefinitely or give wrong re- + fined. Your program may crash or loop indefinitely or give wrong re- sults. PCRE2_PARTIAL_HARD PCRE2_PARTIAL_SOFT These options turn on the partial matching feature. A partial match oc- - curs if the end of the subject string is reached successfully, but + curs if the end of the subject string is reached successfully, but there are not enough subject characters to complete the match. In addi- - tion, either at least one character must have been inspected or the - pattern must contain a lookbehind, or the pattern must be one that + tion, either at least one character must have been inspected or the + pattern must contain a lookbehind, or the pattern must be one that could match an empty string. - If this situation arises when PCRE2_PARTIAL_SOFT (but not PCRE2_PAR- + If this situation arises when PCRE2_PARTIAL_SOFT (but not PCRE2_PAR- TIAL_HARD) is set, matching continues by testing any remaining alterna- - tives. Only if no complete match can be found is PCRE2_ERROR_PARTIAL - returned instead of PCRE2_ERROR_NOMATCH. In other words, PCRE2_PAR- - TIAL_SOFT specifies that the caller is prepared to handle a partial + tives. Only if no complete match can be found is PCRE2_ERROR_PARTIAL + returned instead of PCRE2_ERROR_NOMATCH. In other words, PCRE2_PAR- + TIAL_SOFT specifies that the caller is prepared to handle a partial match, but only if no complete match can be found. - If PCRE2_PARTIAL_HARD is set, it overrides PCRE2_PARTIAL_SOFT. In this - case, if a partial match is found, pcre2_match() immediately returns - PCRE2_ERROR_PARTIAL, without considering any other alternatives. In + If PCRE2_PARTIAL_HARD is set, it overrides PCRE2_PARTIAL_SOFT. In this + case, if a partial match is found, pcre2_match() immediately returns + PCRE2_ERROR_PARTIAL, without considering any other alternatives. In other words, when PCRE2_PARTIAL_HARD is set, a partial match is consid- ered to be more important that an alternative complete match. @@ -2730,38 +2785,38 @@ MATCHING A PATTERN: THE TRADITIONAL FUNCTION NEWLINE HANDLING WHEN MATCHING - When PCRE2 is built, a default newline convention is set; this is usu- - ally the standard convention for the operating system. The default can - be overridden in a compile context by calling pcre2_set_newline(). It - can also be overridden by starting a pattern string with, for example, - (*CRLF), as described in the section on newline conventions in the - pcre2pattern page. During matching, the newline choice affects the be- - haviour of the dot, circumflex, and dollar metacharacters. It may also - alter the way the match starting position is advanced after a match + When PCRE2 is built, a default newline convention is set; this is usu- + ally the standard convention for the operating system. The default can + be overridden in a compile context by calling pcre2_set_newline(). It + can also be overridden by starting a pattern string with, for example, + (*CRLF), as described in the section on newline conventions in the + pcre2pattern page. During matching, the newline choice affects the be- + haviour of the dot, circumflex, and dollar metacharacters. It may also + alter the way the match starting position is advanced after a match failure for an unanchored pattern. When PCRE2_NEWLINE_CRLF, PCRE2_NEWLINE_ANYCRLF, or PCRE2_NEWLINE_ANY is - set as the newline convention, and a match attempt for an unanchored + set as the newline convention, and a match attempt for an unanchored pattern fails when the current starting position is at a CRLF sequence, - and the pattern contains no explicit matches for CR or LF characters, - the match position is advanced by two characters instead of one, in + and the pattern contains no explicit matches for CR or LF characters, + the match position is advanced by two characters instead of one, in other words, to after the CRLF. The above rule is a compromise that makes the most common cases work as - expected. For example, if the pattern is .+A (and the PCRE2_DOTALL op- - tion is not set), it does not match the string "\r\nA" because, after - failing at the start, it skips both the CR and the LF before retrying. - However, the pattern [\r\n]A does match that string, because it con- + expected. For example, if the pattern is .+A (and the PCRE2_DOTALL op- + tion is not set), it does not match the string "\r\nA" because, after + failing at the start, it skips both the CR and the LF before retrying. + However, the pattern [\r\n]A does match that string, because it con- tains an explicit CR or LF reference, and so advances only by one char- acter after the first failure. An explicit match for CR of LF is either a literal appearance of one of - those characters in the pattern, or one of the \r or \n or equivalent + those characters in the pattern, or one of the \r or \n or equivalent octal or hexadecimal escape sequences. Implicit matches such as [^X] do - not count, nor does \s, even though it includes CR and LF in the char- + not count, nor does \s, even though it includes CR and LF in the char- acters that it matches. - Notwithstanding the above, anomalous effects may still occur when CRLF + Notwithstanding the above, anomalous effects may still occur when CRLF is a valid newline sequence and explicit \r or \n escapes appear in the pattern. @@ -2772,82 +2827,82 @@ HOW PCRE2_MATCH() RETURNS A STRING AND CAPTURED SUBSTRINGS PCRE2_SIZE *pcre2_get_ovector_pointer(pcre2_match_data *match_data); - In general, a pattern matches a certain portion of the subject, and in - addition, further substrings from the subject may be picked out by - parenthesized parts of the pattern. Following the usage in Jeffrey - Friedl's book, this is called "capturing" in what follows, and the - phrase "capture group" (Perl terminology) is used for a fragment of a - pattern that picks out a substring. PCRE2 supports several other kinds + In general, a pattern matches a certain portion of the subject, and in + addition, further substrings from the subject may be picked out by + parenthesized parts of the pattern. Following the usage in Jeffrey + Friedl's book, this is called "capturing" in what follows, and the + phrase "capture group" (Perl terminology) is used for a fragment of a + pattern that picks out a substring. PCRE2 supports several other kinds of parenthesized group that do not cause substrings to be captured. The - pcre2_pattern_info() function can be used to find out how many capture + pcre2_pattern_info() function can be used to find out how many capture groups there are in a compiled pattern. - You can use auxiliary functions for accessing captured substrings by + You can use auxiliary functions for accessing captured substrings by number or by name, as described in sections below. Alternatively, you can make direct use of the vector of PCRE2_SIZE val- - ues, called the ovector, which contains the offsets of captured - strings. It is part of the match data block. The function - pcre2_get_ovector_pointer() returns the address of the ovector, and + ues, called the ovector, which contains the offsets of captured + strings. It is part of the match data block. The function + pcre2_get_ovector_pointer() returns the address of the ovector, and pcre2_get_ovector_count() returns the number of pairs of values it con- tains. Within the ovector, the first in each pair of values is set to the off- set of the first code unit of a substring, and the second is set to the - offset of the first code unit after the end of a substring. These val- - ues are always code unit offsets, not character offsets. That is, they + offset of the first code unit after the end of a substring. These val- + ues are always code unit offsets, not character offsets. That is, they are byte offsets in the 8-bit library, 16-bit offsets in the 16-bit li- brary, and 32-bit offsets in the 32-bit library. - After a partial match (error return PCRE2_ERROR_PARTIAL), only the - first pair of offsets (that is, ovector[0] and ovector[1]) are set. - They identify the part of the subject that was partially matched. See + After a partial match (error return PCRE2_ERROR_PARTIAL), only the + first pair of offsets (that is, ovector[0] and ovector[1]) are set. + They identify the part of the subject that was partially matched. See the pcre2partial documentation for details of partial matching. - After a fully successful match, the first pair of offsets identifies - the portion of the subject string that was matched by the entire pat- - tern. The next pair is used for the first captured substring, and so - on. The value returned by pcre2_match() is one more than the highest - numbered pair that has been set. For example, if two substrings have - been captured, the returned value is 3. If there are no captured sub- + After a fully successful match, the first pair of offsets identifies + the portion of the subject string that was matched by the entire pat- + tern. The next pair is used for the first captured substring, and so + on. The value returned by pcre2_match() is one more than the highest + numbered pair that has been set. For example, if two substrings have + been captured, the returned value is 3. If there are no captured sub- strings, the return value from a successful match is 1, indicating that just the first pair of offsets has been set. - If a pattern uses the \K escape sequence within a positive assertion, + If a pattern uses the \K escape sequence within a positive assertion, the reported start of a successful match can be greater than the end of - the match. For example, if the pattern (?=ab\K) is matched against + the match. For example, if the pattern (?=ab\K) is matched against "ab", the start and end offset values for the match are 2 and 0. - If a capture group is matched repeatedly within a single match opera- + If a capture group is matched repeatedly within a single match opera- tion, it is the last portion of the subject that it matched that is re- turned. If the ovector is too small to hold all the captured substring offsets, - as much as possible is filled in, and the function returns a value of - zero. If captured substrings are not of interest, pcre2_match() may be + as much as possible is filled in, and the function returns a value of + zero. If captured substrings are not of interest, pcre2_match() may be called with a match data block whose ovector is of minimum length (that is, one pair). - It is possible for capture group number n+1 to match some part of the - subject when group n has not been used at all. For example, if the + It is possible for capture group number n+1 to match some part of the + subject when group n has not been used at all. For example, if the string "abc" is matched against the pattern (a|(z))(bc) the return from - the function is 4, and groups 1 and 3 are matched, but 2 is not. When - this happens, both values in the offset pairs corresponding to unused + the function is 4, and groups 1 and 3 are matched, but 2 is not. When + this happens, both values in the offset pairs corresponding to unused groups are set to PCRE2_UNSET. - Offset values that correspond to unused groups at the end of the ex- - pression are also set to PCRE2_UNSET. For example, if the string "abc" - is matched against the pattern (abc)(x(yz)?)? groups 2 and 3 are not - matched. The return from the function is 2, because the highest used - capture group number is 1. The offsets for for the second and third - capture groupss (assuming the vector is large enough, of course) are + Offset values that correspond to unused groups at the end of the ex- + pression are also set to PCRE2_UNSET. For example, if the string "abc" + is matched against the pattern (abc)(x(yz)?)? groups 2 and 3 are not + matched. The return from the function is 2, because the highest used + capture group number is 1. The offsets for for the second and third + capture groupss (assuming the vector is large enough, of course) are set to PCRE2_UNSET. Elements in the ovector that do not correspond to capturing parentheses in the pattern are never changed. That is, if a pattern contains n cap- turing parentheses, no more than ovector[0] to ovector[2n+1] are set by - pcre2_match(). The other elements retain whatever values they previ- - ously had. After a failed match attempt, the contents of the ovector + pcre2_match(). The other elements retain whatever values they previ- + ously had. After a failed match attempt, the contents of the ovector are unchanged. @@ -2857,69 +2912,69 @@ OTHER INFORMATION ABOUT A MATCH PCRE2_SIZE pcre2_get_startchar(pcre2_match_data *match_data); - As well as the offsets in the ovector, other information about a match - is retained in the match data block and can be retrieved by the above - functions in appropriate circumstances. If they are called at other + As well as the offsets in the ovector, other information about a match + is retained in the match data block and can be retrieved by the above + functions in appropriate circumstances. If they are called at other times, the result is undefined. - After a successful match, a partial match (PCRE2_ERROR_PARTIAL), or a - failure to match (PCRE2_ERROR_NOMATCH), a mark name may be available. - The function pcre2_get_mark() can be called to access this name, which - can be specified in the pattern by any of the backtracking control + After a successful match, a partial match (PCRE2_ERROR_PARTIAL), or a + failure to match (PCRE2_ERROR_NOMATCH), a mark name may be available. + The function pcre2_get_mark() can be called to access this name, which + can be specified in the pattern by any of the backtracking control verbs, not just (*MARK). The same function applies to all the verbs. It returns a pointer to the zero-terminated name, which is within the com- piled pattern. If no name is available, NULL is returned. The length of - the name (excluding the terminating zero) is stored in the code unit - that precedes the name. You should use this length instead of relying + the name (excluding the terminating zero) is stored in the code unit + that precedes the name. You should use this length instead of relying on the terminating zero if the name might contain a binary zero. - After a successful match, the name that is returned is the last mark + After a successful match, the name that is returned is the last mark name encountered on the matching path through the pattern. Instances of - backtracking verbs without names do not count. Thus, for example, if + backtracking verbs without names do not count. Thus, for example, if the matching path contains (*MARK:A)(*PRUNE), the name "A" is returned. After a "no match" or a partial match, the last encountered name is re- turned. For example, consider this pattern: ^(*MARK:A)((*MARK:B)a|b)c - When it matches "bc", the returned name is A. The B mark is "seen" in - the first branch of the group, but it is not on the matching path. On - the other hand, when this pattern fails to match "bx", the returned + When it matches "bc", the returned name is A. The B mark is "seen" in + the first branch of the group, but it is not on the matching path. On + the other hand, when this pattern fails to match "bx", the returned name is B. - Warning: By default, certain start-of-match optimizations are used to - give a fast "no match" result in some situations. For example, if the - anchoring is removed from the pattern above, there is an initial check - for the presence of "c" in the subject before running the matching en- + Warning: By default, certain start-of-match optimizations are used to + give a fast "no match" result in some situations. For example, if the + anchoring is removed from the pattern above, there is an initial check + for the presence of "c" in the subject before running the matching en- gine. This check fails for "bx", causing a match failure without seeing - any marks. You can disable the start-of-match optimizations by setting - the PCRE2_NO_START_OPTIMIZE option for pcre2_compile() or by starting + any marks. You can disable the start-of-match optimizations by setting + the PCRE2_NO_START_OPTIMIZE option for pcre2_compile() or by starting the pattern with (*NO_START_OPT). - After a successful match, a partial match, or one of the invalid UTF - errors (for example, PCRE2_ERROR_UTF8_ERR5), pcre2_get_startchar() can + After a successful match, a partial match, or one of the invalid UTF + errors (for example, PCRE2_ERROR_UTF8_ERR5), pcre2_get_startchar() can be called. After a successful or partial match it returns the code unit - offset of the character at which the match started. For a non-partial - match, this can be different to the value of ovector[0] if the pattern - contains the \K escape sequence. After a partial match, however, this - value is always the same as ovector[0] because \K does not affect the + offset of the character at which the match started. For a non-partial + match, this can be different to the value of ovector[0] if the pattern + contains the \K escape sequence. After a partial match, however, this + value is always the same as ovector[0] because \K does not affect the result of a partial match. - After a UTF check failure, pcre2_get_startchar() can be used to obtain + After a UTF check failure, pcre2_get_startchar() can be used to obtain the code unit offset of the invalid UTF character. Details are given in the pcre2unicode page. ERROR RETURNS FROM pcre2_match() - If pcre2_match() fails, it returns a negative number. This can be con- - verted to a text string by calling the pcre2_get_error_message() func- - tion (see "Obtaining a textual error message" below). Negative error - codes are also returned by other functions, and are documented with - them. The codes are given names in the header file. If UTF checking is + If pcre2_match() fails, it returns a negative number. This can be con- + verted to a text string by calling the pcre2_get_error_message() func- + tion (see "Obtaining a textual error message" below). Negative error + codes are also returned by other functions, and are documented with + them. The codes are given names in the header file. If UTF checking is in force and an invalid UTF subject string is detected, one of a number - of UTF-specific negative error codes is returned. Details are given in - the pcre2unicode page. The following are the other errors that may be + of UTF-specific negative error codes is returned. Details are given in + the pcre2unicode page. The following are the other errors that may be returned by pcre2_match(): PCRE2_ERROR_NOMATCH @@ -2928,20 +2983,20 @@ ERROR RETURNS FROM pcre2_match() PCRE2_ERROR_PARTIAL - The subject string did not match, but it did match partially. See the + The subject string did not match, but it did match partially. See the pcre2partial documentation for details of partial matching. PCRE2_ERROR_BADMAGIC PCRE2 stores a 4-byte "magic number" at the start of the compiled code, - to catch the case when it is passed a junk pointer. This is the error + to catch the case when it is passed a junk pointer. This is the error that is returned when the magic number is not present. PCRE2_ERROR_BADMODE - This error is given when a compiled pattern is passed to a function in - a library of a different code unit width, for example, a pattern com- - piled by the 8-bit library is passed to a 16-bit or 32-bit library + This error is given when a compiled pattern is passed to a function in + a library of a different code unit width, for example, a pattern com- + piled by the 8-bit library is passed to a 16-bit or 32-bit library function. PCRE2_ERROR_BADOFFSET @@ -2955,15 +3010,15 @@ ERROR RETURNS FROM pcre2_match() PCRE2_ERROR_BADUTFOFFSET The UTF code unit sequence that was passed as a subject was checked and - found to be valid (the PCRE2_NO_UTF_CHECK option was not set), but the - value of startoffset did not point to the beginning of a UTF character + found to be valid (the PCRE2_NO_UTF_CHECK option was not set), but the + value of startoffset did not point to the beginning of a UTF character or the end of the subject. PCRE2_ERROR_CALLOUT - This error is never generated by pcre2_match() itself. It is provided - for use by callout functions that want to cause pcre2_match() or - pcre2_callout_enumerate() to return a distinctive error code. See the + This error is never generated by pcre2_match() itself. It is provided + for use by callout functions that want to cause pcre2_match() or + pcre2_callout_enumerate() to return a distinctive error code. See the pcre2callout documentation for details. PCRE2_ERROR_DEPTHLIMIT @@ -2976,14 +3031,14 @@ ERROR RETURNS FROM pcre2_match() PCRE2_ERROR_INTERNAL - An unexpected internal error has occurred. This error could be caused + An unexpected internal error has occurred. This error could be caused by a bug in PCRE2 or by overwriting of the compiled pattern. PCRE2_ERROR_JIT_STACKLIMIT This error is returned when a pattern that was successfully studied us- ing JIT is being matched, but the memory available for the just-in-time - processing stack is not large enough. See the pcre2jit documentation + processing stack is not large enough. See the pcre2jit documentation for more details. PCRE2_ERROR_MATCHLIMIT @@ -2992,11 +3047,11 @@ ERROR RETURNS FROM pcre2_match() PCRE2_ERROR_NOMEMORY - If a pattern contains many nested backtracking points, heap memory is - used to remember them. This error is given when the memory allocation - function (default or custom) fails. Note that a different error, - PCRE2_ERROR_HEAPLIMIT, is given if the amount of memory needed exceeds - the heap limit. PCRE2_ERROR_NOMEMORY is also returned if + If a pattern contains many nested backtracking points, heap memory is + used to remember them. This error is given when the memory allocation + function (default or custom) fails. Note that a different error, + PCRE2_ERROR_HEAPLIMIT, is given if the amount of memory needed exceeds + the heap limit. PCRE2_ERROR_NOMEMORY is also returned if PCRE2_COPY_MATCHED_SUBJECT is set and memory allocation fails. PCRE2_ERROR_NULL @@ -3005,12 +3060,12 @@ ERROR RETURNS FROM pcre2_match() PCRE2_ERROR_RECURSELOOP - This error is returned when pcre2_match() detects a recursion loop - within the pattern. Specifically, it means that either the whole pat- + This error is returned when pcre2_match() detects a recursion loop + within the pattern. Specifically, it means that either the whole pat- tern or a capture group has been called recursively for the second time - at the same position in the subject string. Some simple patterns that - might do this are detected and faulted at compile time, but more com- - plicated cases, in particular mutual recursions between two different + at the same position in the subject string. Some simple patterns that + might do this are detected and faulted at compile time, but more com- + plicated cases, in particular mutual recursions between two different groups, cannot be detected until matching is attempted. @@ -3019,20 +3074,20 @@ OBTAINING A TEXTUAL ERROR MESSAGE int pcre2_get_error_message(int errorcode, PCRE2_UCHAR *buffer, PCRE2_SIZE bufflen); - A text message for an error code from any PCRE2 function (compile, - match, or auxiliary) can be obtained by calling pcre2_get_error_mes- - sage(). The code is passed as the first argument, with the remaining - two arguments specifying a code unit buffer and its length in code - units, into which the text message is placed. The message is returned - in code units of the appropriate width for the library that is being + A text message for an error code from any PCRE2 function (compile, + match, or auxiliary) can be obtained by calling pcre2_get_error_mes- + sage(). The code is passed as the first argument, with the remaining + two arguments specifying a code unit buffer and its length in code + units, into which the text message is placed. The message is returned + in code units of the appropriate width for the library that is being used. - The returned message is terminated with a trailing zero, and the func- - tion returns the number of code units used, excluding the trailing + The returned message is terminated with a trailing zero, and the func- + tion returns the number of code units used, excluding the trailing zero. If the error number is unknown, the negative error code PCRE2_ER- - ROR_BADDATA is returned. If the buffer is too small, the message is + ROR_BADDATA is returned. If the buffer is too small, the message is truncated (but still with a trailing zero), and the negative error code - PCRE2_ERROR_NOMEMORY is returned. None of the messages are very long; + PCRE2_ERROR_NOMEMORY is returned. None of the messages are very long; a buffer size of 120 code units is ample. @@ -3051,39 +3106,39 @@ EXTRACTING CAPTURED SUBSTRINGS BY NUMBER void pcre2_substring_free(PCRE2_UCHAR *buffer); - Captured substrings can be accessed directly by using the ovector as + Captured substrings can be accessed directly by using the ovector as described above. For convenience, auxiliary functions are provided for - extracting captured substrings as new, separate, zero-terminated + extracting captured substrings as new, separate, zero-terminated strings. A substring that contains a binary zero is correctly extracted - and has a further zero added on the end, but the result is not, of + and has a further zero added on the end, but the result is not, of course, a C string. The functions in this section identify substrings by number. The number zero refers to the entire matched substring, with higher numbers refer- - ring to substrings captured by parenthesized groups. After a partial - match, only substring zero is available. An attempt to extract any - other substring gives the error PCRE2_ERROR_PARTIAL. The next section + ring to substrings captured by parenthesized groups. After a partial + match, only substring zero is available. An attempt to extract any + other substring gives the error PCRE2_ERROR_PARTIAL. The next section describes similar functions for extracting captured substrings by name. - If a pattern uses the \K escape sequence within a positive assertion, + If a pattern uses the \K escape sequence within a positive assertion, the reported start of a successful match can be greater than the end of - the match. For example, if the pattern (?=ab\K) is matched against - "ab", the start and end offset values for the match are 2 and 0. In - this situation, calling these functions with a zero substring number + the match. For example, if the pattern (?=ab\K) is matched against + "ab", the start and end offset values for the match are 2 and 0. In + this situation, calling these functions with a zero substring number extracts a zero-length empty string. - You can find the length in code units of a captured substring without - extracting it by calling pcre2_substring_length_bynumber(). The first - argument is a pointer to the match data block, the second is the group - number, and the third is a pointer to a variable into which the length - is placed. If you just want to know whether or not the substring has + You can find the length in code units of a captured substring without + extracting it by calling pcre2_substring_length_bynumber(). The first + argument is a pointer to the match data block, the second is the group + number, and the third is a pointer to a variable into which the length + is placed. If you just want to know whether or not the substring has been captured, you can pass the third argument as NULL. - The pcre2_substring_copy_bynumber() function copies a captured sub- - string into a supplied buffer, whereas pcre2_substring_get_bynumber() - copies it into new memory, obtained using the same memory allocation - function that was used for the match data block. The first two argu- - ments of these functions are a pointer to the match data block and a + The pcre2_substring_copy_bynumber() function copies a captured sub- + string into a supplied buffer, whereas pcre2_substring_get_bynumber() + copies it into new memory, obtained using the same memory allocation + function that was used for the match data block. The first two argu- + ments of these functions are a pointer to the match data block and a capture group number. The final arguments of pcre2_substring_copy_bynumber() are a pointer to @@ -3092,25 +3147,25 @@ EXTRACTING CAPTURED SUBSTRINGS BY NUMBER for the extracted substring, excluding the terminating zero. For pcre2_substring_get_bynumber() the third and fourth arguments point - to variables that are updated with a pointer to the new memory and the - number of code units that comprise the substring, again excluding the - terminating zero. When the substring is no longer needed, the memory + to variables that are updated with a pointer to the new memory and the + number of code units that comprise the substring, again excluding the + terminating zero. When the substring is no longer needed, the memory should be freed by calling pcre2_substring_free(). - The return value from all these functions is zero for success, or a - negative error code. If the pattern match failed, the match failure - code is returned. If a substring number greater than zero is used af- - ter a partial match, PCRE2_ERROR_PARTIAL is returned. Other possible + The return value from all these functions is zero for success, or a + negative error code. If the pattern match failed, the match failure + code is returned. If a substring number greater than zero is used af- + ter a partial match, PCRE2_ERROR_PARTIAL is returned. Other possible error codes are: PCRE2_ERROR_NOMEMORY - The buffer was too small for pcre2_substring_copy_bynumber(), or the + The buffer was too small for pcre2_substring_copy_bynumber(), or the attempt to get memory failed for pcre2_substring_get_bynumber(). PCRE2_ERROR_NOSUBSTRING - There is no substring with that number in the pattern, that is, the + There is no substring with that number in the pattern, that is, the number is greater than the number of capturing parentheses. PCRE2_ERROR_UNAVAILABLE @@ -3121,8 +3176,8 @@ EXTRACTING CAPTURED SUBSTRINGS BY NUMBER PCRE2_ERROR_UNSET - The substring did not participate in the match. For example, if the - pattern is (abc)|(def) and the subject is "def", and the ovector con- + The substring did not participate in the match. For example, if the + pattern is (abc)|(def) and the subject is "def", and the ovector con- tains at least two capturing slots, substring number 1 is unset. @@ -3133,31 +3188,31 @@ EXTRACTING A LIST OF ALL CAPTURED SUBSTRINGS void pcre2_substring_list_free(PCRE2_SPTR *list); - The pcre2_substring_list_get() function extracts all available sub- - strings and builds a list of pointers to them. It also (optionally) - builds a second list that contains their lengths (in code units), ex- - cluding a terminating zero that is added to each of them. All this is + The pcre2_substring_list_get() function extracts all available sub- + strings and builds a list of pointers to them. It also (optionally) + builds a second list that contains their lengths (in code units), ex- + cluding a terminating zero that is added to each of them. All this is done in a single block of memory that is obtained using the same memory allocation function that was used to get the match data block. - This function must be called only after a successful match. If called + This function must be called only after a successful match. If called after a partial match, the error code PCRE2_ERROR_PARTIAL is returned. - The address of the memory block is returned via listptr, which is also + The address of the memory block is returned via listptr, which is also the start of the list of string pointers. The end of the list is marked - by a NULL pointer. The address of the list of lengths is returned via - lengthsptr. If your strings do not contain binary zeros and you do not + by a NULL pointer. The address of the list of lengths is returned via + lengthsptr. If your strings do not contain binary zeros and you do not therefore need the lengths, you may supply NULL as the lengthsptr argu- - ment to disable the creation of a list of lengths. The yield of the - function is zero if all went well, or PCRE2_ERROR_NOMEMORY if the mem- - ory block could not be obtained. When the list is no longer needed, it + ment to disable the creation of a list of lengths. The yield of the + function is zero if all went well, or PCRE2_ERROR_NOMEMORY if the mem- + ory block could not be obtained. When the list is no longer needed, it should be freed by calling pcre2_substring_list_free(). If this function encounters a substring that is unset, which can happen - when capture group number n+1 matches some part of the subject, but - group n has not been used at all, it returns an empty string. This can + when capture group number n+1 matches some part of the subject, but + group n has not been used at all, it returns an empty string. This can be distinguished from a genuine zero-length substring by inspecting the - appropriate offset in the ovector, which contain PCRE2_UNSET for unset + appropriate offset in the ovector, which contain PCRE2_UNSET for unset substrings, or by calling pcre2_substring_length_bynumber(). @@ -3177,7 +3232,7 @@ EXTRACTING CAPTURED SUBSTRINGS BY NAME void pcre2_substring_free(PCRE2_UCHAR *buffer); - To extract a substring by name, you first have to find associated num- + To extract a substring by name, you first have to find associated num- ber. For example, for this pattern: (a+)b(? \d+)... @@ -3185,32 +3240,32 @@ EXTRACTING CAPTURED SUBSTRINGS BY NAME the number of the capture group called "xxx" is 2. If the name is known to be unique (PCRE2_DUPNAMES was not set), you can find the number from the name by calling pcre2_substring_number_from_name(). The first argu- - ment is the compiled pattern, and the second is the name. The yield of - the function is the group number, PCRE2_ERROR_NOSUBSTRING if there is - no group with that name, or PCRE2_ERROR_NOUNIQUESUBSTRING if there is - more than one group with that name. Given the number, you can extract - the substring directly from the ovector, or use one of the "bynumber" + ment is the compiled pattern, and the second is the name. The yield of + the function is the group number, PCRE2_ERROR_NOSUBSTRING if there is + no group with that name, or PCRE2_ERROR_NOUNIQUESUBSTRING if there is + more than one group with that name. Given the number, you can extract + the substring directly from the ovector, or use one of the "bynumber" functions described above. - For convenience, there are also "byname" functions that correspond to + For convenience, there are also "byname" functions that correspond to the "bynumber" functions, the only difference being that the second ar- - gument is a name instead of a number. If PCRE2_DUPNAMES is set and + gument is a name instead of a number. If PCRE2_DUPNAMES is set and there are duplicate names, these functions scan all the groups with the - given name, and return the captured substring from the first named + given name, and return the captured substring from the first named group that is set. - If there are no groups with the given name, PCRE2_ERROR_NOSUBSTRING is - returned. If all groups with the name have numbers that are greater + If there are no groups with the given name, PCRE2_ERROR_NOSUBSTRING is + returned. If all groups with the name have numbers that are greater than the number of slots in the ovector, PCRE2_ERROR_UNAVAILABLE is re- - turned. If there is at least one group with a slot in the ovector, but + turned. If there is at least one group with a slot in the ovector, but no group is found to be set, PCRE2_ERROR_UNSET is returned. Warning: If the pattern uses the (?| feature to set up multiple capture - groups with the same number, as described in the section on duplicate + groups with the same number, as described in the section on duplicate group numbers in the pcre2pattern page, you cannot use names to distin- - guish the different capture groups, because names are not included in - the compiled code. The matching process uses only numbers. For this - reason, the use of different names for groups with the same number + guish the different capture groups, because names are not included in + the compiled code. The matching process uses only numbers. For this + reason, the use of different names for groups with the same number causes an error at compile time. @@ -3223,126 +3278,126 @@ CREATING A NEW STRING WITH SUBSTITUTIONS PCRE2_SIZE rlength, PCRE2_UCHAR *outputbuffer, PCRE2_SIZE *outlengthptr); - This function optionally calls pcre2_match() and then makes a copy of - the subject string in outputbuffer, replacing parts that were matched - with the replacement string, whose length is supplied in rlength. This - can be given as PCRE2_ZERO_TERMINATED for a zero-terminated string. + This function optionally calls pcre2_match() and then makes a copy of + the subject string in outputbuffer, replacing parts that were matched + with the replacement string, whose length is supplied in rlength. This + can be given as PCRE2_ZERO_TERMINATED for a zero-terminated string. There is an option (see PCRE2_SUBSTITUTE_REPLACEMENT_ONLY below) to re- - turn just the replacement string(s). The default action is to perform - just one replacement if the pattern matches, but there is an option - that requests multiple replacements (see PCRE2_SUBSTITUTE_GLOBAL be- + turn just the replacement string(s). The default action is to perform + just one replacement if the pattern matches, but there is an option + that requests multiple replacements (see PCRE2_SUBSTITUTE_GLOBAL be- low). - If successful, pcre2_substitute() returns the number of substitutions - that were carried out. This may be zero if no match was found, and is - never greater than one unless PCRE2_SUBSTITUTE_GLOBAL is set. A nega- + If successful, pcre2_substitute() returns the number of substitutions + that were carried out. This may be zero if no match was found, and is + never greater than one unless PCRE2_SUBSTITUTE_GLOBAL is set. A nega- tive value is returned if an error is detected. - Matches in which a \K item in a lookahead in the pattern causes the - match to end before it starts are not supported, and give rise to an + Matches in which a \K item in a lookahead in the pattern causes the + match to end before it starts are not supported, and give rise to an error return. For global replacements, matches in which \K in a lookbe- - hind causes the match to start earlier than the point that was reached + hind causes the match to start earlier than the point that was reached in the previous iteration are also not supported. - The first seven arguments of pcre2_substitute() are the same as for + The first seven arguments of pcre2_substitute() are the same as for pcre2_match(), except that the partial matching options are not permit- - ted, and match_data may be passed as NULL, in which case a match data - block is obtained and freed within this function, using memory manage- - ment functions from the match context, if provided, or else those that + ted, and match_data may be passed as NULL, in which case a match data + block is obtained and freed within this function, using memory manage- + ment functions from the match context, if provided, or else those that were used to allocate memory for the compiled code. - If match_data is not NULL and PCRE2_SUBSTITUTE_MATCHED is not set, the + If match_data is not NULL and PCRE2_SUBSTITUTE_MATCHED is not set, the provided block is used for all calls to pcre2_match(), and its contents - afterwards are the result of the final call. For global changes, this + afterwards are the result of the final call. For global changes, this will always be a no-match error. The contents of the ovector within the match data block may or may not have been changed. - As well as the usual options for pcre2_match(), a number of additional - options can be set in the options argument of pcre2_substitute(). One - such option is PCRE2_SUBSTITUTE_MATCHED. When this is set, an external - match_data block must be provided, and it must have been used for an - external call to pcre2_match(). The data in the match_data block (re- + As well as the usual options for pcre2_match(), a number of additional + options can be set in the options argument of pcre2_substitute(). One + such option is PCRE2_SUBSTITUTE_MATCHED. When this is set, an external + match_data block must be provided, and it must have been used for an + external call to pcre2_match(). The data in the match_data block (re- turn code, offset vector) is used for the first substitution instead of - calling pcre2_match() from within pcre2_substitute(). This allows an + calling pcre2_match() from within pcre2_substitute(). This allows an application to check for a match before choosing to substitute, without having to repeat the match. - The contents of the externally supplied match data block are not - changed when PCRE2_SUBSTITUTE_MATCHED is set. If PCRE2_SUBSTI- - TUTE_GLOBAL is also set, pcre2_match() is called after the first sub- - stitution to check for further matches, but this is done using an in- - ternally obtained match data block, thus always leaving the external + The contents of the externally supplied match data block are not + changed when PCRE2_SUBSTITUTE_MATCHED is set. If PCRE2_SUBSTI- + TUTE_GLOBAL is also set, pcre2_match() is called after the first sub- + stitution to check for further matches, but this is done using an in- + ternally obtained match data block, thus always leaving the external block unchanged. - The code argument is not used for matching before the first substitu- - tion when PCRE2_SUBSTITUTE_MATCHED is set, but it must be provided, - even when PCRE2_SUBSTITUTE_GLOBAL is not set, because it contains in- + The code argument is not used for matching before the first substitu- + tion when PCRE2_SUBSTITUTE_MATCHED is set, but it must be provided, + even when PCRE2_SUBSTITUTE_GLOBAL is not set, because it contains in- formation such as the UTF setting and the number of capturing parenthe- ses in the pattern. - The default action of pcre2_substitute() is to return a copy of the + The default action of pcre2_substitute() is to return a copy of the subject string with matched substrings replaced. However, if PCRE2_SUB- - STITUTE_REPLACEMENT_ONLY is set, only the replacement substrings are + STITUTE_REPLACEMENT_ONLY is set, only the replacement substrings are returned. In the global case, multiple replacements are concatenated in - the output buffer. Substitution callouts (see below) can be used to + the output buffer. Substitution callouts (see below) can be used to separate them if necessary. - The outlengthptr argument of pcre2_substitute() must point to a vari- - able that contains the length, in code units, of the output buffer. If - the function is successful, the value is updated to contain the length - in code units of the new string, excluding the trailing zero that is + The outlengthptr argument of pcre2_substitute() must point to a vari- + able that contains the length, in code units, of the output buffer. If + the function is successful, the value is updated to contain the length + in code units of the new string, excluding the trailing zero that is automatically added. - If the function is not successful, the value set via outlengthptr de- - pends on the type of error. For syntax errors in the replacement + If the function is not successful, the value set via outlengthptr de- + pends on the type of error. For syntax errors in the replacement string, the value is the offset in the replacement string where the er- - ror was detected. For other errors, the value is PCRE2_UNSET by de- + ror was detected. For other errors, the value is PCRE2_UNSET by de- fault. This includes the case of the output buffer being too small, un- less PCRE2_SUBSTITUTE_OVERFLOW_LENGTH is set. - PCRE2_SUBSTITUTE_OVERFLOW_LENGTH changes what happens when the output + PCRE2_SUBSTITUTE_OVERFLOW_LENGTH changes what happens when the output buffer is too small. The default action is to return PCRE2_ERROR_NOMEM- - ORY immediately. If this option is set, however, pcre2_substitute() + ORY immediately. If this option is set, however, pcre2_substitute() continues to go through the motions of matching and substituting (with- - out, of course, writing anything) in order to compute the size of buf- - fer that is needed. This value is passed back via the outlengthptr - variable, with the result of the function still being PCRE2_ER- + out, of course, writing anything) in order to compute the size of buf- + fer that is needed. This value is passed back via the outlengthptr + variable, with the result of the function still being PCRE2_ER- ROR_NOMEMORY. - Passing a buffer size of zero is a permitted way of finding out how - much memory is needed for given substitution. However, this does mean + Passing a buffer size of zero is a permitted way of finding out how + much memory is needed for given substitution. However, this does mean that the entire operation is carried out twice. Depending on the appli- - cation, it may be more efficient to allocate a large buffer and free - the excess afterwards, instead of using PCRE2_SUBSTITUTE_OVER- + cation, it may be more efficient to allocate a large buffer and free + the excess afterwards, instead of using PCRE2_SUBSTITUTE_OVER- FLOW_LENGTH. - The replacement string, which is interpreted as a UTF string in UTF - mode, is checked for UTF validity unless PCRE2_NO_UTF_CHECK is set. An + The replacement string, which is interpreted as a UTF string in UTF + mode, is checked for UTF validity unless PCRE2_NO_UTF_CHECK is set. An invalid UTF replacement string causes an immediate return with the rel- evant UTF error code. - If PCRE2_SUBSTITUTE_LITERAL is set, the replacement string is not in- + If PCRE2_SUBSTITUTE_LITERAL is set, the replacement string is not in- terpreted in any way. By default, however, a dollar character is an es- - cape character that can specify the insertion of characters from cap- - ture groups and names from (*MARK) or other control verbs in the pat- + cape character that can specify the insertion of characters from cap- + ture groups and names from (*MARK) or other control verbs in the pat- tern. The following forms are always recognized: $$ insert a dollar character $ or ${ } insert the contents of group $*MARK or ${*MARK} insert a control verb name - Either a group number or a group name can be given for . Curly - brackets are required only if the following character would be inter- + Either a group number or a group name can be given for . Curly + brackets are required only if the following character would be inter- preted as part of the number or name. The number may be zero to include - the entire matched string. For example, if the pattern a(b)c is - matched with "=abc=" and the replacement string "+$1$0$1+", the result + the entire matched string. For example, if the pattern a(b)c is + matched with "=abc=" and the replacement string "+$1$0$1+", the result is "=+babcb+=". - $*MARK inserts the name from the last encountered backtracking control - verb on the matching path that has a name. (*MARK) must always include - a name, but the other verbs need not. For example, in the case of + $*MARK inserts the name from the last encountered backtracking control + verb on the matching path that has a name. (*MARK) must always include + a name, but the other verbs need not. For example, in the case of (*MARK:A)(*PRUNE) the name inserted is "A", but for (*MARK:A)(*PRUNE:B) - the relevant name is "B". This facility can be used to perform simple + the relevant name is "B". This facility can be used to perform simple simultaneous substitutions, as this pcre2test example shows: /(*MARK:pear)apple|(*MARK:orange)lemon/g,replace=${*MARK} @@ -3350,15 +3405,15 @@ CREATING A NEW STRING WITH SUBSTITUTIONS 2: pear orange PCRE2_SUBSTITUTE_GLOBAL causes the function to iterate over the subject - string, replacing every matching substring. If this option is not set, - only the first matching substring is replaced. The search for matches - takes place in the original subject string (that is, previous replace- - ments do not affect it). Iteration is implemented by advancing the - startoffset value for each search, which is always passed the entire + string, replacing every matching substring. If this option is not set, + only the first matching substring is replaced. The search for matches + takes place in the original subject string (that is, previous replace- + ments do not affect it). Iteration is implemented by advancing the + startoffset value for each search, which is always passed the entire subject string. If an offset limit is set in the match context, search- ing stops when that limit is reached. - You can restrict the effect of a global substitution to a portion of + You can restrict the effect of a global substitution to a portion of the subject string by setting either or both of startoffset and an off- set limit. Here is a pcre2test example: @@ -3366,73 +3421,73 @@ CREATING A NEW STRING WITH SUBSTITUTIONS ABC ABC ABC ABC\=offset=3,offset_limit=12 2: ABC A!C A!C ABC - When continuing with global substitutions after matching a substring + When continuing with global substitutions after matching a substring with zero length, an attempt to find a non-empty match at the same off- set is performed. If this is not successful, the offset is advanced by one character except when CRLF is a valid newline sequence and the next - two characters are CR, LF. In this case, the offset is advanced by two + two characters are CR, LF. In this case, the offset is advanced by two characters. PCRE2_SUBSTITUTE_UNKNOWN_UNSET causes references to capture groups that do not appear in the pattern to be treated as unset groups. This option - should be used with care, because it means that a typo in a group name + should be used with care, because it means that a typo in a group name or number no longer causes the PCRE2_ERROR_NOSUBSTRING error. PCRE2_SUBSTITUTE_UNSET_EMPTY causes unset capture groups (including un- - known groups when PCRE2_SUBSTITUTE_UNKNOWN_UNSET is set) to be treated - as empty strings when inserted as described above. If this option is + known groups when PCRE2_SUBSTITUTE_UNKNOWN_UNSET is set) to be treated + as empty strings when inserted as described above. If this option is not set, an attempt to insert an unset group causes the PCRE2_ERROR_UN- - SET error. This option does not influence the extended substitution + SET error. This option does not influence the extended substitution syntax described below. - PCRE2_SUBSTITUTE_EXTENDED causes extra processing to be applied to the - replacement string. Without this option, only the dollar character is - special, and only the group insertion forms listed above are valid. + PCRE2_SUBSTITUTE_EXTENDED causes extra processing to be applied to the + replacement string. Without this option, only the dollar character is + special, and only the group insertion forms listed above are valid. When PCRE2_SUBSTITUTE_EXTENDED is set, two things change: - Firstly, backslash in a replacement string is interpreted as an escape + Firstly, backslash in a replacement string is interpreted as an escape character. The usual forms such as \n or \x{ddd} can be used to specify - particular character codes, and backslash followed by any non-alphanu- - meric character quotes that character. Extended quoting can be coded + particular character codes, and backslash followed by any non-alphanu- + meric character quotes that character. Extended quoting can be coded using \Q...\E, exactly as in pattern strings. - There are also four escape sequences for forcing the case of inserted - letters. The insertion mechanism has three states: no case forcing, + There are also four escape sequences for forcing the case of inserted + letters. The insertion mechanism has three states: no case forcing, force upper case, and force lower case. The escape sequences change the current state: \U and \L change to upper or lower case forcing, respec- - tively, and \E (when not terminating a \Q quoted sequence) reverts to - no case forcing. The sequences \u and \l force the next character (if - it is a letter) to upper or lower case, respectively, and then the + tively, and \E (when not terminating a \Q quoted sequence) reverts to + no case forcing. The sequences \u and \l force the next character (if + it is a letter) to upper or lower case, respectively, and then the state automatically reverts to no case forcing. Case forcing applies to - all inserted characters, including those from capture groups and let- - ters within \Q...\E quoted sequences. If either PCRE2_UTF or PCRE2_UCP - was set when the pattern was compiled, Unicode properties are used for + all inserted characters, including those from capture groups and let- + ters within \Q...\E quoted sequences. If either PCRE2_UTF or PCRE2_UCP + was set when the pattern was compiled, Unicode properties are used for case forcing characters whose code points are greater than 127. Note that case forcing sequences such as \U...\E do not nest. For exam- - ple, the result of processing "\Uaa\LBB\Ecc\E" is "AAbbcc"; the final - \E has no effect. Note also that the PCRE2_ALT_BSUX and PCRE2_EX- + ple, the result of processing "\Uaa\LBB\Ecc\E" is "AAbbcc"; the final + \E has no effect. Note also that the PCRE2_ALT_BSUX and PCRE2_EX- TRA_ALT_BSUX options do not apply to replacement strings. - The second effect of setting PCRE2_SUBSTITUTE_EXTENDED is to add more - flexibility to capture group substitution. The syntax is similar to + The second effect of setting PCRE2_SUBSTITUTE_EXTENDED is to add more + flexibility to capture group substitution. The syntax is similar to that used by Bash: ${ :- } ${ :+ : } - As before, may be a group number or a name. The first form speci- - fies a default value. If group is set, its value is inserted; if - not, is expanded and the result inserted. The second form - specifies strings that are expanded and inserted when group is set - or unset, respectively. The first form is just a convenient shorthand + As before, may be a group number or a name. The first form speci- + fies a default value. If group is set, its value is inserted; if + not, is expanded and the result inserted. The second form + specifies strings that are expanded and inserted when group is set + or unset, respectively. The first form is just a convenient shorthand for ${ :+${ }: } - Backslash can be used to escape colons and closing curly brackets in - the replacement strings. A change of the case forcing state within a - replacement string remains in force afterwards, as shown in this + Backslash can be used to escape colons and closing curly brackets in + the replacement strings. A change of the case forcing state within a + replacement string remains in force afterwards, as shown in this pcre2test example: /(some)?(body)/substitute_extended,replace=${1:+\U:\L}HeLLo @@ -3441,8 +3496,8 @@ CREATING A NEW STRING WITH SUBSTITUTIONS somebody 1: HELLO - The PCRE2_SUBSTITUTE_UNSET_EMPTY option does not affect these extended - substitutions. However, PCRE2_SUBSTITUTE_UNKNOWN_UNSET does cause un- + The PCRE2_SUBSTITUTE_UNSET_EMPTY option does not affect these extended + substitutions. However, PCRE2_SUBSTITUTE_UNKNOWN_UNSET does cause un- known groups in the extended syntax forms to be treated as unset. If PCRE2_SUBSTITUTE_LITERAL is set, PCRE2_SUBSTITUTE_UNKNOWN_UNSET, @@ -3451,37 +3506,37 @@ CREATING A NEW STRING WITH SUBSTITUTIONS Substitution errors - In the event of an error, pcre2_substitute() returns a negative error - code. Except for PCRE2_ERROR_NOMATCH (which is never returned), errors + In the event of an error, pcre2_substitute() returns a negative error + code. Except for PCRE2_ERROR_NOMATCH (which is never returned), errors from pcre2_match() are passed straight back. PCRE2_ERROR_NOSUBSTRING is returned for a non-existent substring inser- tion, unless PCRE2_SUBSTITUTE_UNKNOWN_UNSET is set. PCRE2_ERROR_UNSET is returned for an unset substring insertion (includ- - ing an unknown substring when PCRE2_SUBSTITUTE_UNKNOWN_UNSET is set) - when the simple (non-extended) syntax is used and PCRE2_SUBSTITUTE_UN- + ing an unknown substring when PCRE2_SUBSTITUTE_UNKNOWN_UNSET is set) + when the simple (non-extended) syntax is used and PCRE2_SUBSTITUTE_UN- SET_EMPTY is not set. - PCRE2_ERROR_NOMEMORY is returned if the output buffer is not big + PCRE2_ERROR_NOMEMORY is returned if the output buffer is not big enough. If the PCRE2_SUBSTITUTE_OVERFLOW_LENGTH option is set, the size - of buffer that is needed is returned via outlengthptr. Note that this + of buffer that is needed is returned via outlengthptr. Note that this does not happen by default. PCRE2_ERROR_NULL is returned if PCRE2_SUBSTITUTE_MATCHED is set but the match_data argument is NULL. - PCRE2_ERROR_BADREPLACEMENT is used for miscellaneous syntax errors in - the replacement string, with more particular errors being PCRE2_ER- + PCRE2_ERROR_BADREPLACEMENT is used for miscellaneous syntax errors in + the replacement string, with more particular errors being PCRE2_ER- ROR_BADREPESCAPE (invalid escape sequence), PCRE2_ERROR_REPMISSINGBRACE - (closing curly bracket not found), PCRE2_ERROR_BADSUBSTITUTION (syntax - error in extended group substitution), and PCRE2_ERROR_BADSUBSPATTERN + (closing curly bracket not found), PCRE2_ERROR_BADSUBSTITUTION (syntax + error in extended group substitution), and PCRE2_ERROR_BADSUBSPATTERN (the pattern match ended before it started or the match started earlier - than the current position in the subject, which can happen if \K is + than the current position in the subject, which can happen if \K is used in an assertion). As for all PCRE2 errors, a text message that describes the error can be - obtained by calling the pcre2_get_error_message() function (see "Ob- + obtained by calling the pcre2_get_error_message() function (see "Ob- taining a textual error message" above). Substitution callouts @@ -3490,15 +3545,15 @@ CREATING A NEW STRING WITH SUBSTITUTIONS int (*callout_function)(pcre2_substitute_callout_block *, void *), void *callout_data); - The pcre2_set_substitution_callout() function can be used to specify a - callout function for pcre2_substitute(). This information is passed in + The pcre2_set_substitution_callout() function can be used to specify a + callout function for pcre2_substitute(). This information is passed in a match context. The callout function is called after each substitution has been processed, but it can cause the replacement not to happen. The - callout function is not called for simulated substitutions that happen + callout function is not called for simulated substitutions that happen as a result of the PCRE2_SUBSTITUTE_OVERFLOW_LENGTH option. The first argument of the callout function is a pointer to a substitute - callout block structure, which contains the following fields, not nec- + callout block structure, which contains the following fields, not nec- essarily in this order: uint32_t version; @@ -3509,34 +3564,34 @@ CREATING A NEW STRING WITH SUBSTITUTIONS uint32_t oveccount; PCRE2_SIZE output_offsets[2]; - The version field contains the version number of the block format. The - current version is 0. The version number will increase in future if - more fields are added, but the intention is never to remove any of the + The version field contains the version number of the block format. The + current version is 0. The version number will increase in future if + more fields are added, but the intention is never to remove any of the existing fields. The subscount field is the number of the current match. It is 1 for the first callout, 2 for the second, and so on. The input and output point- ers are copies of the values passed to pcre2_substitute(). - The ovector field points to the ovector, which contains the result of + The ovector field points to the ovector, which contains the result of the most recent match. The oveccount field contains the number of pairs that are set in the ovector, and is always greater than zero. - The output_offsets vector contains the offsets of the replacement in - the output string. This has already been processed for dollar and (if + The output_offsets vector contains the offsets of the replacement in + the output string. This has already been processed for dollar and (if requested) backslash substitutions as described above. - The second argument of the callout function is the value passed as - callout_data when the function was registered. The value returned by + The second argument of the callout function is the value passed as + callout_data when the function was registered. The value returned by the callout function is interpreted as follows: - If the value is zero, the replacement is accepted, and, if PCRE2_SUB- - STITUTE_GLOBAL is set, processing continues with a search for the next - match. If the value is not zero, the current replacement is not ac- - cepted. If the value is greater than zero, processing continues when - PCRE2_SUBSTITUTE_GLOBAL is set. Otherwise (the value is less than zero - or PCRE2_SUBSTITUTE_GLOBAL is not set), the the rest of the input is - copied to the output and the call to pcre2_substitute() exits, return- + If the value is zero, the replacement is accepted, and, if PCRE2_SUB- + STITUTE_GLOBAL is set, processing continues with a search for the next + match. If the value is not zero, the current replacement is not ac- + cepted. If the value is greater than zero, processing continues when + PCRE2_SUBSTITUTE_GLOBAL is set. Otherwise (the value is less than zero + or PCRE2_SUBSTITUTE_GLOBAL is not set), the the rest of the input is + copied to the output and the call to pcre2_substitute() exits, return- ing the number of matches so far. @@ -3545,56 +3600,56 @@ DUPLICATE CAPTURE GROUP NAMES int pcre2_substring_nametable_scan(const pcre2_code *code, PCRE2_SPTR name, PCRE2_SPTR *first, PCRE2_SPTR *last); - When a pattern is compiled with the PCRE2_DUPNAMES option, names for - capture groups are not required to be unique. Duplicate names are al- - ways allowed for groups with the same number, created by using the (?| + When a pattern is compiled with the PCRE2_DUPNAMES option, names for + capture groups are not required to be unique. Duplicate names are al- + ways allowed for groups with the same number, created by using the (?| feature. Indeed, if such groups are named, they are required to use the same names. - Normally, patterns that use duplicate names are such that in any one - match, only one of each set of identically-named groups participates. + Normally, patterns that use duplicate names are such that in any one + match, only one of each set of identically-named groups participates. An example is shown in the pcre2pattern documentation. - When duplicates are present, pcre2_substring_copy_byname() and - pcre2_substring_get_byname() return the first substring corresponding - to the given name that is set. Only if none are set is PCRE2_ERROR_UN- - SET is returned. The pcre2_substring_number_from_name() function re- - turns the error PCRE2_ERROR_NOUNIQUESUBSTRING when there are duplicate + When duplicates are present, pcre2_substring_copy_byname() and + pcre2_substring_get_byname() return the first substring corresponding + to the given name that is set. Only if none are set is PCRE2_ERROR_UN- + SET is returned. The pcre2_substring_number_from_name() function re- + turns the error PCRE2_ERROR_NOUNIQUESUBSTRING when there are duplicate names. - If you want to get full details of all captured substrings for a given - name, you must use the pcre2_substring_nametable_scan() function. The - first argument is the compiled pattern, and the second is the name. If - the third and fourth arguments are NULL, the function returns a group + If you want to get full details of all captured substrings for a given + name, you must use the pcre2_substring_nametable_scan() function. The + first argument is the compiled pattern, and the second is the name. If + the third and fourth arguments are NULL, the function returns a group number for a unique name, or PCRE2_ERROR_NOUNIQUESUBSTRING otherwise. When the third and fourth arguments are not NULL, they must be pointers - to variables that are updated by the function. After it has run, they + to variables that are updated by the function. After it has run, they point to the first and last entries in the name-to-number table for the - given name, and the function returns the length of each entry in code - units. In both cases, PCRE2_ERROR_NOSUBSTRING is returned if there are + given name, and the function returns the length of each entry in code + units. In both cases, PCRE2_ERROR_NOSUBSTRING is returned if there are no entries for the given name. The format of the name table is described above in the section entitled - Information about a pattern. Given all the relevant entries for the - name, you can extract each of their numbers, and hence the captured + Information about a pattern. Given all the relevant entries for the + name, you can extract each of their numbers, and hence the captured data. FINDING ALL POSSIBLE MATCHES AT ONE POSITION - The traditional matching function uses a similar algorithm to Perl, - which stops when it finds the first match at a given point in the sub- + The traditional matching function uses a similar algorithm to Perl, + which stops when it finds the first match at a given point in the sub- ject. If you want to find all possible matches, or the longest possible - match at a given position, consider using the alternative matching - function (see below) instead. If you cannot use the alternative func- + match at a given position, consider using the alternative matching + function (see below) instead. If you cannot use the alternative func- tion, you can kludge it up by making use of the callout facility, which is described in the pcre2callout documentation. What you have to do is to insert a callout right at the end of the pat- - tern. When your callout function is called, extract and save the cur- - rent matched substring. Then return 1, which forces pcre2_match() to - backtrack and try other alternatives. Ultimately, when it runs out of + tern. When your callout function is called, extract and save the cur- + rent matched substring. Then return 1, which forces pcre2_match() to + backtrack and try other alternatives. Ultimately, when it runs out of matches, pcre2_match() will yield PCRE2_ERROR_NOMATCH. @@ -3606,26 +3661,26 @@ MATCHING A PATTERN: THE ALTERNATIVE FUNCTION pcre2_match_context *mcontext, int *workspace, PCRE2_SIZE wscount); - The function pcre2_dfa_match() is called to match a subject string - against a compiled pattern, using a matching algorithm that scans the + The function pcre2_dfa_match() is called to match a subject string + against a compiled pattern, using a matching algorithm that scans the subject string just once (not counting lookaround assertions), and does - not backtrack. This has different characteristics to the normal algo- - rithm, and is not compatible with Perl. Some of the features of PCRE2 - patterns are not supported. Nevertheless, there are times when this - kind of matching can be useful. For a discussion of the two matching + not backtrack. This has different characteristics to the normal algo- + rithm, and is not compatible with Perl. Some of the features of PCRE2 + patterns are not supported. Nevertheless, there are times when this + kind of matching can be useful. For a discussion of the two matching algorithms, and a list of features that pcre2_dfa_match() does not sup- port, see the pcre2matching documentation. - The arguments for the pcre2_dfa_match() function are the same as for + The arguments for the pcre2_dfa_match() function are the same as for pcre2_match(), plus two extras. The ovector within the match data block is used in a different way, and this is described below. The other com- - mon arguments are used in the same way as for pcre2_match(), so their + mon arguments are used in the same way as for pcre2_match(), so their description is not repeated here. - The two additional arguments provide workspace for the function. The - workspace vector should contain at least 20 elements. It is used for + The two additional arguments provide workspace for the function. The + workspace vector should contain at least 20 elements. It is used for keeping track of multiple paths through the pattern tree. More - workspace is needed for patterns and subjects where there are a lot of + workspace is needed for patterns and subjects where there are a lot of potential matches. Here is an example of a simple call to pcre2_dfa_match(): @@ -3645,45 +3700,45 @@ MATCHING A PATTERN: THE ALTERNATIVE FUNCTION Option bits for pcre_dfa_match() - The unused bits of the options argument for pcre2_dfa_match() must be - zero. The only bits that may be set are PCRE2_ANCHORED, - PCRE2_COPY_MATCHED_SUBJECT, PCRE2_ENDANCHORED, PCRE2_NOTBOL, PCRE2_NO- + The unused bits of the options argument for pcre2_dfa_match() must be + zero. The only bits that may be set are PCRE2_ANCHORED, + PCRE2_COPY_MATCHED_SUBJECT, PCRE2_ENDANCHORED, PCRE2_NOTBOL, PCRE2_NO- TEOL, PCRE2_NOTEMPTY, PCRE2_NOTEMPTY_ATSTART, PCRE2_NO_UTF_CHECK, - PCRE2_PARTIAL_HARD, PCRE2_PARTIAL_SOFT, PCRE2_DFA_SHORTEST, and - PCRE2_DFA_RESTART. All but the last four of these are exactly the same + PCRE2_PARTIAL_HARD, PCRE2_PARTIAL_SOFT, PCRE2_DFA_SHORTEST, and + PCRE2_DFA_RESTART. All but the last four of these are exactly the same as for pcre2_match(), so their description is not repeated here. PCRE2_PARTIAL_HARD PCRE2_PARTIAL_SOFT - These have the same general effect as they do for pcre2_match(), but - the details are slightly different. When PCRE2_PARTIAL_HARD is set for - pcre2_dfa_match(), it returns PCRE2_ERROR_PARTIAL if the end of the + These have the same general effect as they do for pcre2_match(), but + the details are slightly different. When PCRE2_PARTIAL_HARD is set for + pcre2_dfa_match(), it returns PCRE2_ERROR_PARTIAL if the end of the subject is reached and there is still at least one matching possibility that requires additional characters. This happens even if some complete - matches have already been found. When PCRE2_PARTIAL_SOFT is set, the - return code PCRE2_ERROR_NOMATCH is converted into PCRE2_ERROR_PARTIAL - if the end of the subject is reached, there have been no complete + matches have already been found. When PCRE2_PARTIAL_SOFT is set, the + return code PCRE2_ERROR_NOMATCH is converted into PCRE2_ERROR_PARTIAL + if the end of the subject is reached, there have been no complete matches, but there is still at least one matching possibility. The por- - tion of the string that was inspected when the longest partial match + tion of the string that was inspected when the longest partial match was found is set as the first matching string in both cases. There is a - more detailed discussion of partial and multi-segment matching, with + more detailed discussion of partial and multi-segment matching, with examples, in the pcre2partial documentation. PCRE2_DFA_SHORTEST - Setting the PCRE2_DFA_SHORTEST option causes the matching algorithm to + Setting the PCRE2_DFA_SHORTEST option causes the matching algorithm to stop as soon as it has found one match. Because of the way the alterna- - tive algorithm works, this is necessarily the shortest possible match + tive algorithm works, this is necessarily the shortest possible match at the first possible matching point in the subject string. PCRE2_DFA_RESTART - When pcre2_dfa_match() returns a partial match, it is possible to call + When pcre2_dfa_match() returns a partial match, it is possible to call it again, with additional subject characters, and have it continue with the same match. The PCRE2_DFA_RESTART option requests this action; when - it is set, the workspace and wscount options must reference the same - vector as before because data about the match so far is left in them + it is set, the workspace and wscount options must reference the same + vector as before because data about the match so far is left in them after a partial match. There is more discussion of this facility in the pcre2partial documentation. @@ -3691,8 +3746,8 @@ MATCHING A PATTERN: THE ALTERNATIVE FUNCTION When pcre2_dfa_match() succeeds, it may have matched more than one sub- string in the subject. Note, however, that all the matches from one run - of the function start at the same point in the subject. The shorter - matches are all initial substrings of the longer matches. For example, + of the function start at the same point in the subject. The shorter + matches are all initial substrings of the longer matches. For example, if the pattern <.*> @@ -3707,94 +3762,94 @@ MATCHING A PATTERN: THE ALTERNATIVE FUNCTION - On success, the yield of the function is a number greater than zero, - which is the number of matched substrings. The offsets of the sub- - strings are returned in the ovector, and can be extracted by number in - the same way as for pcre2_match(), but the numbers bear no relation to - any capture groups that may exist in the pattern, because DFA matching + On success, the yield of the function is a number greater than zero, + which is the number of matched substrings. The offsets of the sub- + strings are returned in the ovector, and can be extracted by number in + the same way as for pcre2_match(), but the numbers bear no relation to + any capture groups that may exist in the pattern, because DFA matching does not support capturing. - Calls to the convenience functions that extract substrings by name re- + Calls to the convenience functions that extract substrings by name re- turn the error PCRE2_ERROR_DFA_UFUNC (unsupported function) if used af- - ter a DFA match. The convenience functions that extract substrings by + ter a DFA match. The convenience functions that extract substrings by number never return PCRE2_ERROR_NOSUBSTRING. - The matched strings are stored in the ovector in reverse order of - length; that is, the longest matching string is first. If there were - too many matches to fit into the ovector, the yield of the function is + The matched strings are stored in the ovector in reverse order of + length; that is, the longest matching string is first. If there were + too many matches to fit into the ovector, the yield of the function is zero, and the vector is filled with the longest matches. - NOTE: PCRE2's "auto-possessification" optimization usually applies to - character repeats at the end of a pattern (as well as internally). For - example, the pattern "a\d+" is compiled as if it were "a\d++". For DFA - matching, this means that only one possible match is found. If you re- + NOTE: PCRE2's "auto-possessification" optimization usually applies to + character repeats at the end of a pattern (as well as internally). For + example, the pattern "a\d+" is compiled as if it were "a\d++". For DFA + matching, this means that only one possible match is found. If you re- ally do want multiple matches in such cases, either use an ungreedy re- - peat such as "a\d+?" or set the PCRE2_NO_AUTO_POSSESS option when com- + peat such as "a\d+?" or set the PCRE2_NO_AUTO_POSSESS option when com- piling. Error returns from pcre2_dfa_match() The pcre2_dfa_match() function returns a negative number when it fails. - Many of the errors are the same as for pcre2_match(), as described + Many of the errors are the same as for pcre2_match(), as described above. There are in addition the following errors that are specific to pcre2_dfa_match(): PCRE2_ERROR_DFA_UITEM - This return is given if pcre2_dfa_match() encounters an item in the - pattern that it does not support, for instance, the use of \C in a UTF + This return is given if pcre2_dfa_match() encounters an item in the + pattern that it does not support, for instance, the use of \C in a UTF mode or a backreference. PCRE2_ERROR_DFA_UCOND - This return is given if pcre2_dfa_match() encounters a condition item + This return is given if pcre2_dfa_match() encounters a condition item that uses a backreference for the condition, or a test for recursion in a specific capture group. These are not supported. PCRE2_ERROR_DFA_UINVALID_UTF - This return is given if pcre2_dfa_match() is called for a pattern that - was compiled with PCRE2_MATCH_INVALID_UTF. This is not supported for + This return is given if pcre2_dfa_match() is called for a pattern that + was compiled with PCRE2_MATCH_INVALID_UTF. This is not supported for DFA matching. PCRE2_ERROR_DFA_WSSIZE - This return is given if pcre2_dfa_match() runs out of space in the + This return is given if pcre2_dfa_match() runs out of space in the workspace vector. PCRE2_ERROR_DFA_RECURSE When a recursion or subroutine call is processed, the matching function - calls itself recursively, using private memory for the ovector and - workspace. This error is given if the internal ovector is not large - enough. This should be extremely rare, as a vector of size 1000 is + calls itself recursively, using private memory for the ovector and + workspace. This error is given if the internal ovector is not large + enough. This should be extremely rare, as a vector of size 1000 is used. PCRE2_ERROR_DFA_BADRESTART - When pcre2_dfa_match() is called with the PCRE2_DFA_RESTART option, - some plausibility checks are made on the contents of the workspace, - which should contain data about the previous partial match. If any of + When pcre2_dfa_match() is called with the PCRE2_DFA_RESTART option, + some plausibility checks are made on the contents of the workspace, + which should contain data about the previous partial match. If any of these checks fail, this error is given. SEE ALSO - pcre2build(3), pcre2callout(3), pcre2demo(3), pcre2matching(3), + pcre2build(3), pcre2callout(3), pcre2demo(3), pcre2matching(3), pcre2partial(3), pcre2posix(3), pcre2sample(3), pcre2unicode(3). AUTHOR Philip Hazel - University Computing Service + Retired from University Computing Service Cambridge, England. REVISION - Last updated: 19 March 2020 - Copyright (c) 1997-2020 University of Cambridge. + Last updated: 30 August 2021 + Copyright (c) 1997-2021 University of Cambridge. ------------------------------------------------------------------------------ @@ -4324,15 +4379,17 @@ DISABLING THE Z AND T FORMATTING MODIFIERS The C99 standard defines formatting modifiers z and t for size_t and ptrdiff_t values, respectively. By default, PCRE2 uses these modifiers - in environments other than Microsoft Visual Studio when __STDC_VER- - SION__ is defined and has a value greater than or equal to 199901L (in- - dicating C99). However, there is at least one environment that claims - to be C99 but does not support these modifiers. If + in environments other than old versions of Microsoft Visual Studio when + __STDC_VERSION__ is defined and has a value greater than or equal to + 199901L (indicating support for C99). However, there is at least one + environment that claims to be C99 but does not support these modifiers. + If --disable-percent-zt is specified, no use is made of the z or t modifiers. Instead of %td or - %zu, %lu is used, with a cast for size_t values. + %zu, a suitable format is used depending in the size of long for the + platform. SUPPORT FOR FUZZERS @@ -4831,10 +4888,10 @@ NAME DIFFERENCES BETWEEN PCRE2 AND PERL - This document describes the differences in the ways that PCRE2 and Perl - handle regular expressions. The differences described here are with re- - spect to Perl versions 5.26, but as both Perl and PCRE2 are continually - changing, the information may sometimes be out of date. + This document describes some of the differences in the ways that PCRE2 + and Perl handle regular expressions. The differences described here are + with respect to Perl version 5.32.0, but as both Perl and PCRE2 are + continually changing, the information may at times be out of date. 1. PCRE2 has only a subset of Perl's Unicode support. Details of what it does have are given in the pcre2unicode page. @@ -4845,40 +4902,43 @@ DIFFERENCES BETWEEN PCRE2 AND PERL serts that the next character is not "a" three times (in principle; PCRE2 optimizes this to run the assertion just once). Perl allows some repeat quantifiers on other assertions, for example, \b* (but not - \b{3}), but these do not seem to have any use. + \b{3}, though oddly it does allow ^{3}), but these do not seem to have + any use. PCRE2 does not allow any kind of quantifier on non-lookaround + assertions. 3. Capture groups that occur inside negative lookaround assertions are counted, but their entries in the offsets vector are set only when a negative assertion is a condition that has a matching branch (that is, - the condition is false). + the condition is false). Perl may set such capture groups in other + circumstances. - 4. The following Perl escape sequences are not supported: \F, \l, \L, + 4. The following Perl escape sequences are not supported: \F, \l, \L, \u, \U, and \N when followed by a character name. \N on its own, match- - ing a non-newline character, and \N{U+dd..}, matching a Unicode code - point, are supported. The escapes that modify the case of following - letters are implemented by Perl's general string-handling and are not + ing a non-newline character, and \N{U+dd..}, matching a Unicode code + point, are supported. The escapes that modify the case of following + letters are implemented by Perl's general string-handling and are not part of its pattern matching engine. If any of these are encountered by - PCRE2, an error is generated by default. However, if either of the - PCRE2_ALT_BSUX or PCRE2_EXTRA_ALT_BSUX options is set, \U and \u are + PCRE2, an error is generated by default. However, if either of the + PCRE2_ALT_BSUX or PCRE2_EXTRA_ALT_BSUX options is set, \U and \u are interpreted as ECMAScript interprets them. 5. The Perl escape sequences \p, \P, and \X are supported only if PCRE2 is built with Unicode support (the default). The properties that can be - tested with \p and \P are limited to the general category properties - such as Lu and Nd, script names such as Greek or Han, and the derived - properties Any and L&. PCRE2 does support the Cs (surrogate) property, - which Perl does not; the Perl documentation says "Because Perl hides - the need for the user to understand the internal representation of Uni- - code characters, there is no need to implement the somewhat messy con- - cept of surrogates." + tested with \p and \P are limited to the general category properties + such as Lu and Nd, script names such as Greek or Han, and the derived + properties Any and L&. Both PCRE2 and Perl support the Cs (surrogate) + property, but in PCRE2 its use is limited. See the pcre2pattern docu- + mentation for details. The long synonyms for property names that Perl + supports (such as \p{Letter}) are not supported by PCRE2, nor is it + permitted to prefix any of these properties with "Is". 6. PCRE2 supports the \Q...\E escape for quoting substrings. Characters in between are treated as literals. However, this is slightly different - from Perl in that $ and @ are also handled as literals inside the + from Perl in that $ and @ are also handled as literals inside the quotes. In Perl, they cause variable interpolation (but of course PCRE2 does not have variables). Also, Perl does "double-quotish backslash in- terpolation" on any backslashes between \Q and \E which, its documenta- - tion says, "may lead to confusing results". PCRE2 treats a backslash + tion says, "may lead to confusing results". PCRE2 treats a backslash between \Q and \E just like any other character. Note the following ex- amples: @@ -4891,78 +4951,81 @@ DIFFERENCES BETWEEN PCRE2 AND PERL \QA\B\E A\B A\B \Q\\E \ \\E - The \Q...\E sequence is recognized both inside and outside character - classes. + The \Q...\E sequence is recognized both inside and outside character + classes by both PCRE2 and Perl. - 7. Fairly obviously, PCRE2 does not support the (?{code}) and + 7. Fairly obviously, PCRE2 does not support the (?{code}) and (??{code}) constructions. However, PCRE2 does have a "callout" feature, which allows an external function to be called during pattern matching. See the pcre2callout documentation for details. - 8. Subroutine calls (whether recursive or not) were treated as atomic - groups up to PCRE2 release 10.23, but from release 10.30 this changed, + 8. Subroutine calls (whether recursive or not) were treated as atomic + groups up to PCRE2 release 10.23, but from release 10.30 this changed, and backtracking into subroutine calls is now supported, as in Perl. - 9. If any of the backtracking control verbs are used in a group that is - called as a subroutine (whether or not recursively), their effect is - confined to that group; it does not extend to the surrounding pattern. - This is not always the case in Perl. In particular, if (*THEN) is - present in a group that is called as a subroutine, its action is lim- - ited to that group, even if the group does not contain any | charac- - ters. Note that such groups are processed as anchored at the point - where they are tested. - - 10. If a pattern contains more than one backtracking control verb, the - first one that is backtracked onto acts. For example, in the pattern - A(*COMMIT)B(*PRUNE)C a failure in B triggers (*COMMIT), but a failure + 9. In PCRE2, if any of the backtracking control verbs are used in a + group that is called as a subroutine (whether or not recursively), + their effect is confined to that group; it does not extend to the sur- + rounding pattern. This is not always the case in Perl. In particular, + if (*THEN) is present in a group that is called as a subroutine, its + action is limited to that group, even if the group does not contain any + | characters. Note that such groups are processed as anchored at the + point where they are tested. + + 10. If a pattern contains more than one backtracking control verb, the + first one that is backtracked onto acts. For example, in the pattern + A(*COMMIT)B(*PRUNE)C a failure in B triggers (*COMMIT), but a failure in C triggers (*PRUNE). Perl's behaviour is more complex; in many cases it is the same as PCRE2, but there are cases where it differs. - 11. Most backtracking verbs in assertions have their normal actions. - They are not confined to the assertion. - - 12. There are some differences that are concerned with the settings of + 11. There are some differences that are concerned with the settings of captured strings when part of a pattern is repeated. For example, matching "aba" against the pattern /^(a(b)?)+$/ in Perl leaves $2 un- set, but in PCRE2 it is set to "b". - 13. PCRE2's handling of duplicate capture group numbers and names is + 12. PCRE2's handling of duplicate capture group numbers and names is not as general as Perl's. This is a consequence of the fact the PCRE2 works internally just with numbers, using an external table to trans- late between numbers and names. In particular, a pattern such as - (?|(?A)|(?B), where the two capture groups have the same number + (?|(?A)|(?B)), where the two capture groups have the same number but different names, is not supported, and causes an error at compile time. If it were allowed, it would not be possible to distinguish which group matched, because both names map to capture group number 1. To avoid this confusing situation, an error is given at compile time. - 14. Perl used to recognize comments in some places that PCRE2 does not, + 13. Perl used to recognize comments in some places that PCRE2 does not, for example, between the ( and ? at the start of a group. If the /x modifier is set, Perl allowed white space between ( and ? though the latest Perls give an error (for a while it was just deprecated). There may still be some cases where Perl behaves differently. - 15. Perl, when in warning mode, gives warnings for character classes + 14. Perl, when in warning mode, gives warnings for character classes such as [A-\d] or [a-[:digit:]]. It then treats the hyphens as liter- als. PCRE2 has no warning features, so it gives an error in these cases because they are almost certainly user mistakes. - 16. In PCRE2, the upper/lower case character properties Lu and Ll are + 15. In PCRE2, the upper/lower case character properties Lu and Ll are not affected when case-independent matching is specified. For example, \p{Lu} always matches an upper case letter. I think Perl has changed in - this respect; in the release at the time of writing (5.24), \p{Lu} and + this respect; in the release at the time of writing (5.32), \p{Lu} and \p{Ll} match all letters, regardless of case, when case independence is specified. + 16. From release 5.32.0, Perl locks out the use of \K in lookaround as- + sertions. From release 10.38 PCRE2 does the same by default. However, + there is an option for re-enabling the previous behaviour. When this + option is set, \K is acted on when it occurs in positive assertions, + but is ignored in negative assertions. + 17. PCRE2 provides some extensions to the Perl regular expression fa- - cilities. Perl 5.10 includes new features that are not in earlier ver- - sions of Perl, some of which (such as named parentheses) were in PCRE2 - for some time before. This list is with respect to Perl 5.26: + cilities. Perl 5.10 included new features that were not in earlier + versions of Perl, some of which (such as named parentheses) were in + PCRE2 for some time before. This list is with respect to Perl 5.32: (a) Although lookbehind assertions in PCRE2 must match fixed length - strings, each alternative branch of a lookbehind assertion can match a - different length of string. Perl requires them all to have the same - length. + strings, each alternative toplevel branch of a lookbehind assertion can + match a different length of string. Perl requires them all to have the + same length. (b) From PCRE2 10.23, backreferences to groups of fixed length are sup- ported in lookbehinds, provided that there is no possibility of refer- @@ -4997,7 +5060,7 @@ DIFFERENCES BETWEEN PCRE2 AND PERL different way and is not Perl-compatible. (l) PCRE2 recognizes some special sequences such as (*CR) or (*NO_JIT) - at the start of a pattern that set overall options that cannot be + at the start of a pattern. These set overall options that cannot be changed within the pattern. (m) PCRE2 supports non-atomic positive lookaround assertions. This is @@ -5020,14 +5083,14 @@ DIFFERENCES BETWEEN PCRE2 AND PERL AUTHOR Philip Hazel - University Computing Service + Retired from University Computing Service Cambridge, England. REVISION - Last updated: 13 July 2019 - Copyright (c) 1997-2019 University of Cambridge. + Last updated: 30 August 2021 + Copyright (c) 1997-2021 University of Cambridge. ------------------------------------------------------------------------------ @@ -5065,6 +5128,7 @@ AVAILABILITY OF JIT SUPPORT ARM 32-bit (v5, v7, and Thumb2) ARM 64-bit + IBM s390x 64 bit Intel x86 32-bit and 64-bit MIPS 32-bit and 64-bit Power PC 32-bit and 64-bit @@ -5284,7 +5348,7 @@ CONTROLLING THE JIT STACK This is a suggestion for how a multithreaded program that needs to set up non-default JIT stacks might operate: - During thread initalization + During thread initialization thread_local_var = pcre2_jit_stack_create(...) During thread exit @@ -5592,8 +5656,8 @@ THE STANDARD MATCHING ALGORITHM that point the algorithm stops. Thus, if there is more than one possi- ble match, this algorithm returns the first one that it finds. Whether this is the shortest, the longest, or some intermediate length depends - on the way the greedy and ungreedy repetition quantifiers are specified - in the pattern. + on the way the alternations and the greedy or ungreedy repetition quan- + tifiers are specified in the pattern. Because it ends up with a single path through the tree, it is rela- tively straightforward for this algorithm to keep track of the sub- @@ -5622,12 +5686,18 @@ THE ALTERNATIVE MATCHING ALGORITHM represent the different matching possibilities (if there are none, the match has failed). Thus, if there is more than one possible match, this algorithm finds all of them, and in particular, it finds the long- - est. The matches are returned in decreasing order of length. There is - an option to stop the algorithm after the first match (which is neces- - sarily the shortest) is found. + est. The matches are returned in the output vector in decreasing order + of length. There is an option to stop the algorithm after the first + match (which is necessarily the shortest) is found. - Note that all the matches that are found start at the same point in the - subject. If the pattern + Note that the size of vector needed to contain all the results depends + on the number of simultaneous matches, not on the number of parentheses + in the pattern. Using pcre2_match_data_create_from_pattern() to create + the match data block is therefore not advisable when doing DFA match- + ing. + + Note also that all the matches that are found start at the same point + in the subject. If the pattern cat(er(pillar)?)? @@ -5703,50 +5773,45 @@ THE ALTERNATIVE MATCHING ALGORITHM ADVANTAGES OF THE ALTERNATIVE ALGORITHM - Using the alternative matching algorithm provides the following advan- - tages: - - 1. All possible matches (at a single point in the subject) are automat- - ically found, and in particular, the longest match is found. To find - more than one match using the standard algorithm, you have to do kludgy + The main advantage of the alternative algorithm is that all possible + matches (at a single point in the subject) are automatically found, and + in particular, the longest match is found. To find more than one match + at the same point using the standard algorithm, you have to do kludgy things with callouts. - 2. Because the alternative algorithm scans the subject string just - once, and never needs to backtrack (except for lookbehinds), it is pos- - sible to pass very long subject strings to the matching function in - several pieces, checking for partial matching each time. Although it is - also possible to do multi-segment matching using the standard algo- - rithm, by retaining partially matched substrings, it is more compli- - cated. The pcre2partial documentation gives details of partial matching - and discusses multi-segment matching. + Partial matching is possible with this algorithm, though it has some + limitations. The pcre2partial documentation gives details of partial + matching and discusses multi-segment matching. DISADVANTAGES OF THE ALTERNATIVE ALGORITHM The alternative algorithm suffers from a number of disadvantages: - 1. It is substantially slower than the standard algorithm. This is - partly because it has to search for all possible matches, but is also + 1. It is substantially slower than the standard algorithm. This is + partly because it has to search for all possible matches, but is also because it is less susceptible to optimization. - 2. Capturing parentheses, backreferences, script runs, and matching + 2. Capturing parentheses, backreferences, script runs, and matching within invalid UTF string are not supported. 3. Although atomic groups are supported, their use does not provide the performance advantage that it does for the standard algorithm. + 4. JIT optimization is not supported. + AUTHOR Philip Hazel - University Computing Service + Retired from University Computing Service Cambridge, England. REVISION - Last updated: 23 May 2019 - Copyright (c) 1997-2019 University of Cambridge. + Last updated: 28 August 2021 + Copyright (c) 1997-2021 University of Cambridge. ------------------------------------------------------------------------------ @@ -6353,8 +6418,12 @@ CHARACTERS AND METACHARACTERS The quick brown fox matches a portion of a subject string that is identical to itself. When - caseless matching is specified (the PCRE2_CASELESS option), letters are - matched independently of case. + caseless matching is specified (the PCRE2_CASELESS option or (?i) + within the pattern), letters are matched independently of case. Note + that there are two ASCII characters, K and S, that, in addition to + their lower case ASCII equivalents, are case-equivalent with Unicode + U+212A (Kelvin sign) and U+017F (long S) respectively when either + PCRE2_UTF or PCRE2_UCP is set. The power of regular expressions comes from the ability to include wild cards, character classes, alternatives, and repetitions in the pattern. @@ -6389,6 +6458,18 @@ CHARACTERS AND METACHARACTERS [ POSIX character class (if followed by POSIX syntax) ] terminates the character class + If a pattern is compiled with the PCRE2_EXTENDED option, most white + space in the pattern, other than in a character class, and characters + between a # outside a character class and the next newline, inclusive, + are ignored. An escaping backslash can be used to include a white space + or a # character as part of the pattern. If the PCRE2_EXTENDED_MORE op- + tion is set, the same applies, but in addition unescaped space and hor- + izontal tab characters are ignored inside a character class. Note: only + these two characters are ignored, not the full set of pattern white + space characters that are ignored outside a character class. Option + settings can be changed within a pattern; see the section entitled "In- + ternal Option Setting" below. + The following sections describe the use of each of the metacharacters. @@ -6406,15 +6487,9 @@ BACKSLASH that it stands for itself. In particular, if you want to match a back- slash, you write \\. - In a UTF mode, only ASCII digits and letters have any special meaning - after a backslash. All other characters (in particular, those whose - code points are greater than 127) are treated as literals. - - If a pattern is compiled with the PCRE2_EXTENDED option, most white - space in the pattern (other than in a character class), and characters - between a # outside a character class and the next newline, inclusive, - are ignored. An escaping backslash can be used to include a white space - or # character as part of the pattern. + Only ASCII digits and letters have any special meaning after a back- + slash. All other characters (in particular, those whose code points are + greater than 127) are treated as literals. If you want to treat all characters in a sequence as literals, you can do so by putting them between \Q and \E. This is different from Perl in @@ -6764,7 +6839,7 @@ BACKSLASH It is possible to restrict \R to match only CR, LF, or CRLF (instead of the complete set of Unicode line endings) by setting the option - PCRE2_BSR_ANYCRLF at compile time. (BSR is an abbrevation for "back- + PCRE2_BSR_ANYCRLF at compile time. (BSR is an abbreviation for "back- slash R".) This can be made the default when PCRE2 is built; if this is the case, the other behaviour can be requested via the PCRE2_BSR_UNI- CODE option. It is also possible to specify these settings by starting @@ -6826,27 +6901,27 @@ BACKSLASH nese, Bamum, Bassa_Vah, Batak, Bengali, Bhaiksuki, Bopomofo, Brahmi, Braille, Buginese, Buhid, Canadian_Aboriginal, Carian, Caucasian_Alba- nian, Chakma, Cham, Cherokee, Chorasmian, Common, Coptic, Cuneiform, - Cypriot, Cyrillic, Deseret, Devanagari, Dives_Akuru, Dogra, Duployan, - Egyptian_Hieroglyphs, Elbasan, Elymaic, Ethiopic, Georgian, Glagolitic, - Gothic, Grantha, Greek, Gujarati, Gunjala_Gondi, Gurmukhi, Han, Hangul, - Hanifi_Rohingya, Hanunoo, Hatran, Hebrew, Hiragana, Imperial_Aramaic, - Inherited, Inscriptional_Pahlavi, Inscriptional_Parthian, Javanese, - Kaithi, Kannada, Katakana, Kayah_Li, Kharoshthi, Khitan_Small_Script, - Khmer, Khojki, Khudawadi, Lao, Latin, Lepcha, Limbu, Linear_A, Lin- - ear_B, Lisu, Lycian, Lydian, Mahajani, Makasar, Malayalam, Mandaic, - Manichaean, Marchen, Masaram_Gondi, Medefaidrin, Meetei_Mayek, - Mende_Kikakui, Meroitic_Cursive, Meroitic_Hieroglyphs, Miao, Modi, Mon- - golian, Mro, Multani, Myanmar, Nabataean, Nandinagari, New_Tai_Lue, - Newa, Nko, Nushu, Nyakeng_Puachue_Hmong, Ogham, Ol_Chiki, Old_Hungar- - ian, Old_Italic, Old_North_Arabian, Old_Permic, Old_Persian, Old_Sog- - dian, Old_South_Arabian, Old_Turkic, Oriya, Osage, Osmanya, Pa- - hawh_Hmong, Palmyrene, Pau_Cin_Hau, Phags_Pa, Phoenician, - Psalter_Pahlavi, Rejang, Runic, Samaritan, Saurashtra, Sharada, Sha- - vian, Siddham, SignWriting, Sinhala, Sogdian, Sora_Sompeng, Soyombo, - Sundanese, Syloti_Nagri, Syriac, Tagalog, Tagbanwa, Tai_Le, Tai_Tham, - Tai_Viet, Takri, Tamil, Tangut, Telugu, Thaana, Thai, Tibetan, Tifi- - nagh, Tirhuta, Ugaritic, Unknown, Vai, Wancho, Warang_Citi, Yezidi, Yi, - Zanabazar_Square. + Cypriot, Cypro_Minoan, Cyrillic, Deseret, Devanagari, Dives_Akuru, Do- + gra, Duployan, Egyptian_Hieroglyphs, Elbasan, Elymaic, Ethiopic, Geor- + gian, Glagolitic, Gothic, Grantha, Greek, Gujarati, Gunjala_Gondi, Gur- + mukhi, Han, Hangul, Hanifi_Rohingya, Hanunoo, Hatran, Hebrew, Hiragana, + Imperial_Aramaic, Inherited, Inscriptional_Pahlavi, Inscrip- + tional_Parthian, Javanese, Kaithi, Kannada, Katakana, Kayah_Li, + Kharoshthi, Khitan_Small_Script, Khmer, Khojki, Khudawadi, Lao, Latin, + Lepcha, Limbu, Linear_A, Linear_B, Lisu, Lycian, Lydian, Mahajani, + Makasar, Malayalam, Mandaic, Manichaean, Marchen, Masaram_Gondi, Mede- + faidrin, Meetei_Mayek, Mende_Kikakui, Meroitic_Cursive, Meroitic_Hiero- + glyphs, Miao, Modi, Mongolian, Mro, Multani, Myanmar, Nabataean, Nandi- + nagari, New_Tai_Lue, Newa, Nko, Nushu, Nyakeng_Puachue_Hmong, Ogham, + Ol_Chiki, Old_Hungarian, Old_Italic, Old_North_Arabian, Old_Permic, + Old_Persian, Old_Sogdian, Old_South_Arabian, Old_Turkic, Old_Uyghur, + Oriya, Osage, Osmanya, Pahawh_Hmong, Palmyrene, Pau_Cin_Hau, Phags_Pa, + Phoenician, Psalter_Pahlavi, Rejang, Runic, Samaritan, Saurashtra, + Sharada, Shavian, Siddham, SignWriting, Sinhala, Sogdian, Sora_Sompeng, + Soyombo, Sundanese, Syloti_Nagri, Syriac, Tagalog, Tagbanwa, Tai_Le, + Tai_Tham, Tai_Viet, Takri, Tamil, Tangsa, Tangut, Telugu, Thaana, Thai, + Tibetan, Tifinagh, Tirhuta, Toto, Ugaritic, Unknown, Vai, Vithkuqi, + Wancho, Warang_Citi, Yezidi, Yi, Zanabazar_Square. Each character has exactly one Unicode general category property, spec- ified by a two-letter abbreviation. For compatibility with Perl, nega- @@ -6964,8 +7039,8 @@ BACKSLASH 3. Do not break Hangul (a Korean script) syllable sequences. Hangul characters are of five types: L, V, T, LV, and LVT. An L character may be followed by an L, V, LV, or LVT character; an LV or V character may - be followed by a V or T character; an LVT or T character may be follwed - only by a T character. + be followed by a V or T character; an LVT or T character may be fol- + lowed only by a T character. 4. Do not end before extending characters or spacing marks or the "zero-width joiner" character. Characters with the "mark" property al- @@ -7039,27 +7114,30 @@ BACKSLASH matches "foobar", the first substring is still set to "foo". - Perl documents that the use of \K within assertions is "not well de- - fined". In PCRE2, \K is acted upon when it occurs inside positive as- - sertions, but is ignored in negative assertions. Note that when a pat- - tern such as (?=ab\K) matches, the reported start of the match can be - greater than the end of the match. Using \K in a lookbehind assertion - at the start of a pattern can also lead to odd effects. For example, - consider this pattern: + From version 5.32.0 Perl forbids the use of \K in lookaround asser- + tions. From release 10.38 PCRE2 also forbids this by default. However, + the PCRE2_EXTRA_ALLOW_LOOKAROUND_BSK option can be used when calling + pcre2_compile() to re-enable the previous behaviour. When this option + is set, \K is acted upon when it occurs inside positive assertions, but + is ignored in negative assertions. Note that when a pattern such as + (?=ab\K) matches, the reported start of the match can be greater than + the end of the match. Using \K in a lookbehind assertion at the start + of a pattern can also lead to odd effects. For example, consider this + pattern: (?<=\Kfoo)bar - If the subject is "foobar", a call to pcre2_match() with a starting - offset of 3 succeeds and reports the matching string as "foobar", that - is, the start of the reported match is earlier than where the match + If the subject is "foobar", a call to pcre2_match() with a starting + offset of 3 succeeds and reports the matching string as "foobar", that + is, the start of the reported match is earlier than where the match started. Simple assertions - The final use of backslash is for certain simple assertions. An asser- - tion specifies a condition that has to be met at a particular point in - a match, without consuming any characters from the subject string. The - use of groups for more complicated assertions is described below. The + The final use of backslash is for certain simple assertions. An asser- + tion specifies a condition that has to be met at a particular point in + a match, without consuming any characters from the subject string. The + use of groups for more complicated assertions is described below. The backslashed assertions are: \b matches at a word boundary @@ -7070,191 +7148,191 @@ BACKSLASH \z matches only at the end of the subject \G matches at the first matching position in the subject - Inside a character class, \b has a different meaning; it matches the - backspace character. If any other of these assertions appears in a + Inside a character class, \b has a different meaning; it matches the + backspace character. If any other of these assertions appears in a character class, an "invalid escape sequence" error is generated. - A word boundary is a position in the subject string where the current - character and the previous character do not both match \w or \W (i.e. - one matches \w and the other matches \W), or the start or end of the - string if the first or last character matches \w, respectively. When - PCRE2 is built with Unicode support, the meanings of \w and \W can be + A word boundary is a position in the subject string where the current + character and the previous character do not both match \w or \W (i.e. + one matches \w and the other matches \W), or the start or end of the + string if the first or last character matches \w, respectively. When + PCRE2 is built with Unicode support, the meanings of \w and \W can be changed by setting the PCRE2_UCP option. When this is done, it also af- - fects \b and \B. Neither PCRE2 nor Perl has a separate "start of word" - or "end of word" metasequence. However, whatever follows \b normally - determines which it is. For example, the fragment \ba matches "a" at + fects \b and \B. Neither PCRE2 nor Perl has a separate "start of word" + or "end of word" metasequence. However, whatever follows \b normally + determines which it is. For example, the fragment \ba matches "a" at the start of a word. - The \A, \Z, and \z assertions differ from the traditional circumflex + The \A, \Z, and \z assertions differ from the traditional circumflex and dollar (described in the next section) in that they only ever match - at the very start and end of the subject string, whatever options are - set. Thus, they are independent of multiline mode. These three asser- - tions are not affected by the PCRE2_NOTBOL or PCRE2_NOTEOL options, - which affect only the behaviour of the circumflex and dollar metachar- - acters. However, if the startoffset argument of pcre2_match() is non- - zero, indicating that matching is to start at a point other than the - beginning of the subject, \A can never match. The difference between - \Z and \z is that \Z matches before a newline at the end of the string + at the very start and end of the subject string, whatever options are + set. Thus, they are independent of multiline mode. These three asser- + tions are not affected by the PCRE2_NOTBOL or PCRE2_NOTEOL options, + which affect only the behaviour of the circumflex and dollar metachar- + acters. However, if the startoffset argument of pcre2_match() is non- + zero, indicating that matching is to start at a point other than the + beginning of the subject, \A can never match. The difference between + \Z and \z is that \Z matches before a newline at the end of the string as well as at the very end, whereas \z matches only at the end. - The \G assertion is true only when the current matching position is at - the start point of the matching process, as specified by the startoff- - set argument of pcre2_match(). It differs from \A when the value of - startoffset is non-zero. By calling pcre2_match() multiple times with - appropriate arguments, you can mimic Perl's /g option, and it is in + The \G assertion is true only when the current matching position is at + the start point of the matching process, as specified by the startoff- + set argument of pcre2_match(). It differs from \A when the value of + startoffset is non-zero. By calling pcre2_match() multiple times with + appropriate arguments, you can mimic Perl's /g option, and it is in this kind of implementation where \G can be useful. - Note, however, that PCRE2's implementation of \G, being true at the - starting character of the matching process, is subtly different from - Perl's, which defines it as true at the end of the previous match. In - Perl, these can be different when the previously matched string was + Note, however, that PCRE2's implementation of \G, being true at the + starting character of the matching process, is subtly different from + Perl's, which defines it as true at the end of the previous match. In + Perl, these can be different when the previously matched string was empty. Because PCRE2 does just one match at a time, it cannot reproduce this behaviour. - If all the alternatives of a pattern begin with \G, the expression is + If all the alternatives of a pattern begin with \G, the expression is anchored to the starting match position, and the "anchored" flag is set in the compiled regular expression. CIRCUMFLEX AND DOLLAR - The circumflex and dollar metacharacters are zero-width assertions. - That is, they test for a particular condition being true without con- + The circumflex and dollar metacharacters are zero-width assertions. + That is, they test for a particular condition being true without con- suming any characters from the subject string. These two metacharacters - are concerned with matching the starts and ends of lines. If the new- - line convention is set so that only the two-character sequence CRLF is - recognized as a newline, isolated CR and LF characters are treated as + are concerned with matching the starts and ends of lines. If the new- + line convention is set so that only the two-character sequence CRLF is + recognized as a newline, isolated CR and LF characters are treated as ordinary data characters, and are not recognized as newlines. Outside a character class, in the default matching mode, the circumflex - character is an assertion that is true only if the current matching - point is at the start of the subject string. If the startoffset argu- - ment of pcre2_match() is non-zero, or if PCRE2_NOTBOL is set, circum- - flex can never match if the PCRE2_MULTILINE option is unset. Inside a - character class, circumflex has an entirely different meaning (see be- + character is an assertion that is true only if the current matching + point is at the start of the subject string. If the startoffset argu- + ment of pcre2_match() is non-zero, or if PCRE2_NOTBOL is set, circum- + flex can never match if the PCRE2_MULTILINE option is unset. Inside a + character class, circumflex has an entirely different meaning (see be- low). - Circumflex need not be the first character of the pattern if a number - of alternatives are involved, but it should be the first thing in each - alternative in which it appears if the pattern is ever to match that - branch. If all possible alternatives start with a circumflex, that is, - if the pattern is constrained to match only at the start of the sub- - ject, it is said to be an "anchored" pattern. (There are also other + Circumflex need not be the first character of the pattern if a number + of alternatives are involved, but it should be the first thing in each + alternative in which it appears if the pattern is ever to match that + branch. If all possible alternatives start with a circumflex, that is, + if the pattern is constrained to match only at the start of the sub- + ject, it is said to be an "anchored" pattern. (There are also other constructs that can cause a pattern to be anchored.) - The dollar character is an assertion that is true only if the current - matching point is at the end of the subject string, or immediately be- - fore a newline at the end of the string (by default), unless PCRE2_NO- - TEOL is set. Note, however, that it does not actually match the new- - line. Dollar need not be the last character of the pattern if a number - of alternatives are involved, but it should be the last item in any - branch in which it appears. Dollar has no special meaning in a charac- + The dollar character is an assertion that is true only if the current + matching point is at the end of the subject string, or immediately be- + fore a newline at the end of the string (by default), unless PCRE2_NO- + TEOL is set. Note, however, that it does not actually match the new- + line. Dollar need not be the last character of the pattern if a number + of alternatives are involved, but it should be the last item in any + branch in which it appears. Dollar has no special meaning in a charac- ter class. - The meaning of dollar can be changed so that it matches only at the - very end of the string, by setting the PCRE2_DOLLAR_ENDONLY option at + The meaning of dollar can be changed so that it matches only at the + very end of the string, by setting the PCRE2_DOLLAR_ENDONLY option at compile time. This does not affect the \Z assertion. The meanings of the circumflex and dollar metacharacters are changed if - the PCRE2_MULTILINE option is set. When this is the case, a dollar - character matches before any newlines in the string, as well as at the - very end, and a circumflex matches immediately after internal newlines - as well as at the start of the subject string. It does not match after - a newline that ends the string, for compatibility with Perl. However, + the PCRE2_MULTILINE option is set. When this is the case, a dollar + character matches before any newlines in the string, as well as at the + very end, and a circumflex matches immediately after internal newlines + as well as at the start of the subject string. It does not match after + a newline that ends the string, for compatibility with Perl. However, this can be changed by setting the PCRE2_ALT_CIRCUMFLEX option. - For example, the pattern /^abc$/ matches the subject string "def\nabc" - (where \n represents a newline) in multiline mode, but not otherwise. - Consequently, patterns that are anchored in single line mode because - all branches start with ^ are not anchored in multiline mode, and a - match for circumflex is possible when the startoffset argument of - pcre2_match() is non-zero. The PCRE2_DOLLAR_ENDONLY option is ignored + For example, the pattern /^abc$/ matches the subject string "def\nabc" + (where \n represents a newline) in multiline mode, but not otherwise. + Consequently, patterns that are anchored in single line mode because + all branches start with ^ are not anchored in multiline mode, and a + match for circumflex is possible when the startoffset argument of + pcre2_match() is non-zero. The PCRE2_DOLLAR_ENDONLY option is ignored if PCRE2_MULTILINE is set. - When the newline convention (see "Newline conventions" below) recog- - nizes the two-character sequence CRLF as a newline, this is preferred, - even if the single characters CR and LF are also recognized as new- - lines. For example, if the newline convention is "any", a multiline - mode circumflex matches before "xyz" in the string "abc\r\nxyz" rather - than after CR, even though CR on its own is a valid newline. (It also + When the newline convention (see "Newline conventions" below) recog- + nizes the two-character sequence CRLF as a newline, this is preferred, + even if the single characters CR and LF are also recognized as new- + lines. For example, if the newline convention is "any", a multiline + mode circumflex matches before "xyz" in the string "abc\r\nxyz" rather + than after CR, even though CR on its own is a valid newline. (It also matches at the very start of the string, of course.) - Note that the sequences \A, \Z, and \z can be used to match the start - and end of the subject in both modes, and if all branches of a pattern - start with \A it is always anchored, whether or not PCRE2_MULTILINE is + Note that the sequences \A, \Z, and \z can be used to match the start + and end of the subject in both modes, and if all branches of a pattern + start with \A it is always anchored, whether or not PCRE2_MULTILINE is set. FULL STOP (PERIOD, DOT) AND \N Outside a character class, a dot in the pattern matches any one charac- - ter in the subject string except (by default) a character that signi- + ter in the subject string except (by default) a character that signi- fies the end of a line. - When a line ending is defined as a single character, dot never matches - that character; when the two-character sequence CRLF is used, dot does - not match CR if it is immediately followed by LF, but otherwise it - matches all characters (including isolated CRs and LFs). When any Uni- - code line endings are being recognized, dot does not match CR or LF or + When a line ending is defined as a single character, dot never matches + that character; when the two-character sequence CRLF is used, dot does + not match CR if it is immediately followed by LF, but otherwise it + matches all characters (including isolated CRs and LFs). When any Uni- + code line endings are being recognized, dot does not match CR or LF or any of the other line ending characters. - The behaviour of dot with regard to newlines can be changed. If the - PCRE2_DOTALL option is set, a dot matches any one character, without - exception. If the two-character sequence CRLF is present in the sub- + The behaviour of dot with regard to newlines can be changed. If the + PCRE2_DOTALL option is set, a dot matches any one character, without + exception. If the two-character sequence CRLF is present in the sub- ject string, it takes two dots to match it. - The handling of dot is entirely independent of the handling of circum- - flex and dollar, the only relationship being that they both involve + The handling of dot is entirely independent of the handling of circum- + flex and dollar, the only relationship being that they both involve newlines. Dot has no special meaning in a character class. - The escape sequence \N when not followed by an opening brace behaves - like a dot, except that it is not affected by the PCRE2_DOTALL option. - In other words, it matches any character except one that signifies the + The escape sequence \N when not followed by an opening brace behaves + like a dot, except that it is not affected by the PCRE2_DOTALL option. + In other words, it matches any character except one that signifies the end of a line. When \N is followed by an opening brace it has a different meaning. See - the section entitled "Non-printing characters" above for details. Perl - also uses \N{name} to specify characters by Unicode name; PCRE2 does + the section entitled "Non-printing characters" above for details. Perl + also uses \N{name} to specify characters by Unicode name; PCRE2 does not support this. MATCHING A SINGLE CODE UNIT - Outside a character class, the escape sequence \C matches any one code - unit, whether or not a UTF mode is set. In the 8-bit library, one code - unit is one byte; in the 16-bit library it is a 16-bit unit; in the - 32-bit library it is a 32-bit unit. Unlike a dot, \C always matches - line-ending characters. The feature is provided in Perl in order to + Outside a character class, the escape sequence \C matches any one code + unit, whether or not a UTF mode is set. In the 8-bit library, one code + unit is one byte; in the 16-bit library it is a 16-bit unit; in the + 32-bit library it is a 32-bit unit. Unlike a dot, \C always matches + line-ending characters. The feature is provided in Perl in order to match individual bytes in UTF-8 mode, but it is unclear how it can use- fully be used. - Because \C breaks up characters into individual code units, matching - one unit with \C in UTF-8 or UTF-16 mode means that the rest of the + Because \C breaks up characters into individual code units, matching + one unit with \C in UTF-8 or UTF-16 mode means that the rest of the string may start with a malformed UTF character. This has undefined re- sults, because PCRE2 assumes that it is matching character by character in a valid UTF string (by default it checks the subject string's valid- - ity at the start of processing unless the PCRE2_NO_UTF_CHECK or + ity at the start of processing unless the PCRE2_NO_UTF_CHECK or PCRE2_MATCH_INVALID_UTF option is used). - An application can lock out the use of \C by setting the - PCRE2_NEVER_BACKSLASH_C option when compiling a pattern. It is also + An application can lock out the use of \C by setting the + PCRE2_NEVER_BACKSLASH_C option when compiling a pattern. It is also possible to build PCRE2 with the use of \C permanently disabled. - PCRE2 does not allow \C to appear in lookbehind assertions (described - below) in UTF-8 or UTF-16 modes, because this would make it impossible - to calculate the length of the lookbehind. Neither the alternative + PCRE2 does not allow \C to appear in lookbehind assertions (described + below) in UTF-8 or UTF-16 modes, because this would make it impossible + to calculate the length of the lookbehind. Neither the alternative matching function pcre2_dfa_match() nor the JIT optimizer support \C in these UTF modes. The former gives a match-time error; the latter fails to optimize and so the match is always run using the interpreter. - In the 32-bit library, however, \C is always supported (when not ex- - plicitly locked out) because it always matches a single code unit, + In the 32-bit library, however, \C is always supported (when not ex- + plicitly locked out) because it always matches a single code unit, whether or not UTF-32 is specified. In general, the \C escape sequence is best avoided. However, one way of - using it that avoids the problem of malformed UTF-8 or UTF-16 charac- - ters is to use a lookahead to check the length of the next character, - as in this pattern, which could be used with a UTF-8 string (ignore + using it that avoids the problem of malformed UTF-8 or UTF-16 charac- + ters is to use a lookahead to check the length of the next character, + as in this pattern, which could be used with a UTF-8 string (ignore white space and line breaks): (?| (?=[\x00-\x7f])(\C) | @@ -7262,11 +7340,11 @@ MATCHING A SINGLE CODE UNIT (?=[\x{800}-\x{ffff}])(\C)(\C)(\C) | (?=[\x{10000}-\x{1fffff}])(\C)(\C)(\C)(\C)) - In this example, a group that starts with (?| resets the capturing - parentheses numbers in each alternative (see "Duplicate Group Numbers" + In this example, a group that starts with (?| resets the capturing + parentheses numbers in each alternative (see "Duplicate Group Numbers" below). The assertions at the start of each branch check the next UTF-8 - character for values whose encoding uses 1, 2, 3, or 4 bytes, respec- - tively. The character's individual bytes are then captured by the ap- + character for values whose encoding uses 1, 2, 3, or 4 bytes, respec- + tively. The character's individual bytes are then captured by the ap- propriate number of \C groups. @@ -7274,34 +7352,37 @@ SQUARE BRACKETS AND CHARACTER CLASSES An opening square bracket introduces a character class, terminated by a closing square bracket. A closing square bracket on its own is not spe- - cial by default. If a closing square bracket is required as a member + cial by default. If a closing square bracket is required as a member of the class, it should be the first data character in the class (after - an initial circumflex, if present) or escaped with a backslash. This - means that, by default, an empty class cannot be defined. However, if - the PCRE2_ALLOW_EMPTY_CLASS option is set, a closing square bracket at + an initial circumflex, if present) or escaped with a backslash. This + means that, by default, an empty class cannot be defined. However, if + the PCRE2_ALLOW_EMPTY_CLASS option is set, a closing square bracket at the start does end the (empty) class. - A character class matches a single character in the subject. A matched + A character class matches a single character in the subject. A matched character must be in the set of characters defined by the class, unless - the first character in the class definition is a circumflex, in which + the first character in the class definition is a circumflex, in which case the subject character must not be in the set defined by the class. - If a circumflex is actually required as a member of the class, ensure + If a circumflex is actually required as a member of the class, ensure it is not the first character, or escape it with a backslash. - For example, the character class [aeiou] matches any lower case vowel, - while [^aeiou] matches any character that is not a lower case vowel. + For example, the character class [aeiou] matches any lower case vowel, + while [^aeiou] matches any character that is not a lower case vowel. Note that a circumflex is just a convenient notation for specifying the - characters that are in the class by enumerating those that are not. A - class that starts with a circumflex is not an assertion; it still con- - sumes a character from the subject string, and therefore it fails if + characters that are in the class by enumerating those that are not. A + class that starts with a circumflex is not an assertion; it still con- + sumes a character from the subject string, and therefore it fails if the current pointer is at the end of the string. - Characters in a class may be specified by their code points using \o, - \x, or \N{U+hh..} in the usual way. When caseless matching is set, any - letters in a class represent both their upper case and lower case ver- - sions, so for example, a caseless [aeiou] matches "A" as well as "a", - and a caseless [^aeiou] does not match "A", whereas a caseful version - would. + Characters in a class may be specified by their code points using \o, + \x, or \N{U+hh..} in the usual way. When caseless matching is set, any + letters in a class represent both their upper case and lower case ver- + sions, so for example, a caseless [aeiou] matches "A" as well as "a", + and a caseless [^aeiou] does not match "A", whereas a caseful version + would. Note that there are two ASCII characters, K and S, that, in ad- + dition to their lower case ASCII equivalents, are case-equivalent with + Unicode U+212A (Kelvin sign) and U+017F (long S) respectively when ei- + ther PCRE2_UTF or PCRE2_UCP is set. Characters that might indicate line breaks are never treated in any special way when matching character classes, whatever line-ending se- @@ -8660,7 +8741,7 @@ CONDITIONAL GROUPS (?(DEFINE) (? 2[0-4]\d | 25[0-5] | 1\d\d | [1-9]?\d) ) \b (?&byte) (\.(?&byte)){3} \b - The first part of the pattern is a DEFINE group inside which a another + The first part of the pattern is a DEFINE group inside which another group named "byte" is defined. This matches an individual component of an IPv4 address (a number less than 256). When matching takes place, this part of the pattern is skipped because DEFINE acts like a false @@ -9332,7 +9413,7 @@ BACKTRACKING CONTROL If the subject is "aaaac...", after the first match attempt fails (starting at the first character in the string), the starting point skips on to start the next attempt at "c". Note that a possessive quan- - tifer does not have the same effect as this example; although it would + tifier does not have the same effect as this example; although it would suppress backtracking during the first match attempt, the second at- tempt would start at the second character instead of skipping on to "c". @@ -9553,14 +9634,14 @@ SEE ALSO AUTHOR Philip Hazel - University Computing Service + Retired from University Computing Service Cambridge, England. REVISION - Last updated: 24 February 2020 - Copyright (c) 1997-2020 University of Cambridge. + Last updated: 30 August 2021 + Copyright (c) 1997-2021 University of Cambridge. ------------------------------------------------------------------------------ @@ -9844,11 +9925,15 @@ DESCRIPTION an application. Because the POSIX functions call the native ones, it is also necessary to add -lpcre2-8. - Although they are not defined as protypes in pcre2posix.h, the library - does contain functions with the POSIX names regcomp() etc. These simply - pass their arguments to the PCRE2 functions. These functions are pro- - vided for backwards compatibility with earlier versions of PCRE2, so - that existing programs do not have to be recompiled. + Although they were not defined as protypes in pcre2posix.h, releases + 10.33 to 10.36 of the library contained functions with the POSIX names + regcomp() etc. These simply passed their arguments to the PCRE2 func- + tions. These functions were provided for backwards compatibility with + earlier versions of PCRE2, which had only POSIX names. However, this + has proved troublesome in situations where a program links with several + libraries, some of which use PCRE2's POSIX interface while others use + the real POSIX functions. For this reason, the POSIX names have been + removed since release 10.37. Calling the header file pcre2posix.h avoids any conflict with other POSIX libraries. It can, of course, be renamed or aliased as regex.h, @@ -10124,8 +10209,8 @@ AUTHOR REVISION - Last updated: 30 January 2019 - Copyright (c) 1997-2019 University of Cambridge. + Last updated: 26 April 2021 + Copyright (c) 1997-2021 University of Cambridge. ------------------------------------------------------------------------------ @@ -10571,27 +10656,27 @@ SCRIPT NAMES FOR \p AND \P nese, Bamum, Bassa_Vah, Batak, Bengali, Bhaiksuki, Bopomofo, Brahmi, Braille, Buginese, Buhid, Canadian_Aboriginal, Carian, Caucasian_Alba- nian, Chakma, Cham, Cherokee, Chorasmian, Common, Coptic, Cuneiform, - Cypriot, Cyrillic, Deseret, Devanagari, Dives_Akuru, Dogra, Duployan, - Egyptian_Hieroglyphs, Elbasan, Elymaic, Ethiopic, Georgian, Glagolitic, - Gothic, Grantha, Greek, Gujarati, Gunjala_Gondi, Gurmukhi, Han, Hangul, - Hanifi_Rohingya, Hanunoo, Hatran, Hebrew, Hiragana, Imperial_Aramaic, - Inherited, Inscriptional_Pahlavi, Inscriptional_Parthian, Javanese, - Kaithi, Kannada, Katakana, Kayah_Li, Kharoshthi, Khitan_Small_Script, - Khmer, Khojki, Khudawadi, Lao, Latin, Lepcha, Limbu, Linear_A, Lin- - ear_B, Lisu, Lycian, Lydian, Mahajani, Makasar, Malayalam, Mandaic, - Manichaean, Marchen, Masaram_Gondi, Medefaidrin, Meetei_Mayek, - Mende_Kikakui, Meroitic_Cursive, Meroitic_Hieroglyphs, Miao, Modi, Mon- - golian, Mro, Multani, Myanmar, Nabataean, Nandinagari, New_Tai_Lue, - Newa, Nko, Nushu, Nyakeng_Puachue_Hmong, Ogham, Ol_Chiki, Old_Hungar- - ian, Old_Italic, Old_North_Arabian, Old_Permic, Old_Persian, Old_Sog- - dian, Old_South_Arabian, Old_Turkic, Oriya, Osage, Osmanya, Pa- - hawh_Hmong, Palmyrene, Pau_Cin_Hau, Phags_Pa, Phoenician, - Psalter_Pahlavi, Rejang, Runic, Samaritan, Saurashtra, Sharada, Sha- - vian, Siddham, SignWriting, Sinhala, Sogdian, Sora_Sompeng, Soyombo, - Sundanese, Syloti_Nagri, Syriac, Tagalog, Tagbanwa, Tai_Le, Tai_Tham, - Tai_Viet, Takri, Tamil, Tangut, Telugu, Thaana, Thai, Tibetan, Tifi- - nagh, Tirhuta, Ugaritic, Vai, Wancho, Warang_Citi, Yezidi, Yi, Zan- - abazar_Square. + Cypriot, Cypro_Minoan, Cyrillic, Deseret, Devanagari, Dives_Akuru, Do- + gra, Duployan, Egyptian_Hieroglyphs, Elbasan, Elymaic, Ethiopic, Geor- + gian, Glagolitic, Gothic, Grantha, Greek, Gujarati, Gunjala_Gondi, Gur- + mukhi, Han, Hangul, Hanifi_Rohingya, Hanunoo, Hatran, Hebrew, Hiragana, + Imperial_Aramaic, Inherited, Inscriptional_Pahlavi, Inscrip- + tional_Parthian, Javanese, Kaithi, Kannada, Katakana, Kayah_Li, + Kharoshthi, Khitan_Small_Script, Khmer, Khojki, Khudawadi, Lao, Latin, + Lepcha, Limbu, Linear_A, Linear_B, Lisu, Lycian, Lydian, Mahajani, + Makasar, Malayalam, Mandaic, Manichaean, Marchen, Masaram_Gondi, Mede- + faidrin, Meetei_Mayek, Mende_Kikakui, Meroitic_Cursive, Meroitic_Hiero- + glyphs, Miao, Modi, Mongolian, Mro, Multani, Myanmar, Nabataean, Nandi- + nagari, New_Tai_Lue, Newa, Nko, Nushu, Nyakeng_Puachue_Hmong, Ogham, + Ol_Chiki, Old_Hungarian, Old_Italic, Old_North_Arabian, Old_Permic, + Old_Persian, Old_Sogdian, Old_South_Arabian, Old_Turkic, Old_Uyghur, + Oriya, Osage, Osmanya, Pahawh_Hmong, Palmyrene, Pau_Cin_Hau, Phags_Pa, + Phoenician, Psalter_Pahlavi, Rejang, Runic, Samaritan, Saurashtra, + Sharada, Shavian, Siddham, SignWriting, Sinhala, Sogdian, Sora_Sompeng, + Soyombo, Sundanese, Syloti_Nagri, Syriac, Tagalog, Tagbanwa, Tai_Le, + Tai_Tham, Tai_Viet, Takri, Tamil, Tangsa, Tangut, Telugu, Thaana, Thai, + Tibetan, Tifinagh, Tirhuta, Toto, Ugaritic, Vai, Vithkuqi, Wancho, + Warang_Citi, Yezidi, Yi, Zanabazar_Square. CHARACTER CLASSES @@ -10663,7 +10748,11 @@ REPORTED MATCH POINT SETTING \K set reported start of match - \K is honoured in positive assertions, but ignored in negative ones. + From release 10.38 \K is not permitted by default in lookaround asser- + tions, for compatibility with Perl. However, if the PCRE2_EXTRA_AL- + LOW_LOOKAROUND_BSK option is set, the previous behaviour is re-enabled. + When this option is set, \K is honoured in positive assertions, but ig- + nored in negative ones. ALTERNATION @@ -10913,14 +11002,14 @@ SEE ALSO AUTHOR Philip Hazel - University Computing Service + Retired from University Computing Service Cambridge, England. REVISION - Last updated: 28 December 2019 - Copyright (c) 1997-2019 University of Cambridge. + Last updated: 30 August 2021 + Copyright (c) 1997-2021 University of Cambridge. ------------------------------------------------------------------------------ diff --git a/pcre2/doc/pcre2_dfa_match.3 b/pcre2/doc/pcre2_dfa_match.3 index 6413cb6..ea87aac 100644 --- a/pcre2/doc/pcre2_dfa_match.3 +++ b/pcre2/doc/pcre2_dfa_match.3 @@ -1,4 +1,4 @@ -.TH PCRE2_DFA_MATCH 3 "16 October 2018" "PCRE2 10.33" +.TH PCRE2_DFA_MATCH 3 "28 August 2021" "PCRE2 10.38" .SH NAME PCRE2 - Perl-compatible regular expressions (revised API) .SH SYNOPSIS @@ -33,10 +33,15 @@ just once (except when processing lookaround assertions). This function is \fIworkspace\fP Points to a vector of ints used as working space \fIwscount\fP Number of elements in the vector .sp -For \fBpcre2_dfa_match()\fP, a match context is needed only if you want to set -up a callout function or specify the heap limit or the match or the recursion -depth limits. The \fIlength\fP and \fIstartoffset\fP values are code units, not -characters. The options are: +The size of output vector needed to contain all the results depends on the +number of simultaneous matches, not on the number of parentheses in the +pattern. Using \fBpcre2_match_data_create_from_pattern()\fP to create the match +data block is therefore not advisable when using this function. +.P +A match context is needed only if you want to set up a callout function or +specify the heap limit or the match or the recursion depth limits. The +\fIlength\fP and \fIstartoffset\fP values are code units, not characters. The +options are: .sp PCRE2_ANCHORED Match only at the first position PCRE2_COPY_MATCHED_SUBJECT diff --git a/pcre2/doc/pcre2_match_data_create.3 b/pcre2/doc/pcre2_match_data_create.3 index 3b0a29e..439dea3 100644 --- a/pcre2/doc/pcre2_match_data_create.3 +++ b/pcre2/doc/pcre2_match_data_create.3 @@ -1,4 +1,4 @@ -.TH PCRE2_MATCH_DATA_CREATE 3 "29 July 2015" "PCRE2 10.21" +.TH PCRE2_MATCH_DATA_CREATE 3 "28 August 2021" "PCRE2 10.38" .SH NAME PCRE2 - Perl-compatible regular expressions (revised API) .SH SYNOPSIS @@ -18,8 +18,9 @@ This function creates a new match data block, which is used for holding the result of a match. The first argument specifies the number of pairs of offsets that are required. These form the "output vector" (ovector) within the match data block, and are used to identify the matched string and any captured -substrings. There is always one pair of offsets; if \fBovecsize\fP is zero, it -is treated as one. +substrings when matching with \fBpcre2_match()\fP, or a number of different +matches at the same point when used with \fBpcre2_dfa_match()\fP. There is +always one pair of offsets; if \fBovecsize\fP is zero, it is treated as one. .P The second argument points to a general context, for custom memory management, or is NULL for system memory management. The result of the function is NULL if diff --git a/pcre2/doc/pcre2_match_data_create_from_pattern.3 b/pcre2/doc/pcre2_match_data_create_from_pattern.3 index 60bf77c..37486dd 100644 --- a/pcre2/doc/pcre2_match_data_create_from_pattern.3 +++ b/pcre2/doc/pcre2_match_data_create_from_pattern.3 @@ -1,4 +1,4 @@ -.TH PCRE2_MATCH_DATA_CREATE_FROM_PATTERN 3 "29 July 2015" "PCRE2 10.21" +.TH PCRE2_MATCH_DATA_CREATE_FROM_PATTERN 3 "28 August 2021" "PCRE2 10.38" .SH NAME PCRE2 - Perl-compatible regular expressions (revised API) .SH SYNOPSIS @@ -14,12 +14,15 @@ PCRE2 - Perl-compatible regular expressions (revised API) .SH DESCRIPTION .rs .sp -This function creates a new match data block, which is used for holding the -result of a match. The first argument points to a compiled pattern. The number -of capturing parentheses within the pattern is used to compute the number of -pairs of offsets that are required in the match data block. These form the -"output vector" (ovector) within the match data block, and are used to identify -the matched string and any captured substrings. +This function creates a new match data block for holding the result of a match. +The first argument points to a compiled pattern. The number of capturing +parentheses within the pattern is used to compute the number of pairs of +offsets that are required in the match data block. These form the "output +vector" (ovector) within the match data block, and are used to identify the +matched string and any captured substrings when matching with +\fBpcre2_match()\fP. If you are using \fBpcre2_dfa_match()\fP, which uses the +outut vector in a different way, you should use \fBpcre2_match_data_create()\fP +instead of this function. .P The second argument points to a general context, for custom memory management, or is NULL to use the same memory allocator as was used for the compiled diff --git a/pcre2/doc/pcre2_set_compile_extra_options.3 b/pcre2/doc/pcre2_set_compile_extra_options.3 index 764a75e..58cefe5 100644 --- a/pcre2/doc/pcre2_set_compile_extra_options.3 +++ b/pcre2/doc/pcre2_set_compile_extra_options.3 @@ -1,4 +1,4 @@ -.TH PCRE2_SET_COMPILE_EXTRA_OPTIONS 3 "11 February 2019" "PCRE2 10.33" +.TH PCRE2_SET_COMPILE_EXTRA_OPTIONS 3 "31 August 2021" "PCRE2 10.38" .SH NAME PCRE2 - Perl-compatible regular expressions (revised API) .SH SYNOPSIS @@ -19,11 +19,12 @@ housed in a compile context. It completely replaces all the bits. The extra options are: .sp .\" JOIN + PCRE2_EXTRA_ALLOW_LOOKAROUND_BSK Allow \eK in lookarounds PCRE2_EXTRA_ALLOW_SURROGATE_ESCAPES Allow \ex{df800} to \ex{dfff} in UTF-8 and UTF-32 modes .\" JOIN - PCRE2_EXTRA_ALT_BSUX Extended alternate \eu, \eU, and \ex - handling + PCRE2_EXTRA_ALT_BSUX Extended alternate \eu, \eU, and + \ex handling .\" JOIN PCRE2_EXTRA_BAD_ESCAPE_IS_LITERAL Treat all invalid escapes as a literal following character diff --git a/pcre2/doc/pcre2api.3 b/pcre2/doc/pcre2api.3 index 8c581a0..1ad6e26 100644 --- a/pcre2/doc/pcre2api.3 +++ b/pcre2/doc/pcre2api.3 @@ -1,4 +1,4 @@ -.TH PCRE2API 3 "19 March 2020" "PCRE2 10.35" +.TH PCRE2API 3 "30 August 2021" "PCRE2 10.38" .SH NAME PCRE2 - Perl-compatible regular expressions (revised API) .sp @@ -564,24 +564,53 @@ documentation for more details. .P In a more complicated situation, where patterns are compiled only when they are first needed, but are still shared between threads, pointers to compiled -patterns must be protected from simultaneous writing by multiple threads, at -least until a pattern has been compiled. The logic can be something like this: +patterns must be protected from simultaneous writing by multiple threads. This +is somewhat tricky to do correctly. If you know that writing to a pointer is +atomic in your environment, you can use logic like this: .sp Get a read-only (shared) lock (mutex) for pointer if (pointer == NULL) { Get a write (unique) lock for pointer - pointer = pcre2_compile(... + if (pointer == NULL) pointer = pcre2_compile(... } Release the lock Use pointer in pcre2_match() .sp Of course, testing for compilation errors should also be included in the code. .P -If JIT is being used, but the JIT compilation is not being done immediately, -(perhaps waiting to see if the pattern is used often enough) similar logic is -required. JIT compilation updates a pointer within the compiled code block, so -a thread must gain unique write access to the pointer before calling +The reason for checking the pointer a second time is as follows: Several +threads may have acquired the shared lock and tested the pointer for being +NULL, but only one of them will be given the write lock, with the rest kept +waiting. The winning thread will compile the pattern and store the result. +After this thread releases the write lock, another thread will get it, and if +it does not retest pointer for being NULL, will recompile the pattern and +overwrite the pointer, creating a memory leak and possibly causing other +issues. +.P +In an environment where writing to a pointer may not be atomic, the above logic +is not sufficient. The thread that is doing the compiling may be descheduled +after writing only part of the pointer, which could cause other threads to use +an invalid value. Instead of checking the pointer itself, a separate "pointer +is valid" flag (that can be updated atomically) must be used: +.sp + Get a read-only (shared) lock (mutex) for pointer + if (!pointer_is_valid) + { + Get a write (unique) lock for pointer + if (!pointer_is_valid) + { + pointer = pcre2_compile(... + pointer_is_valid = TRUE + } + } + Release the lock + Use pointer in pcre2_match() +.sp +If JIT is being used, but the JIT compilation is not being done immediately +(perhaps waiting to see if the pattern is used often enough), similar logic is +required. JIT compilation updates a value within the compiled code block, so a +thread must gain unique write access to the pointer before calling \fBpcre2_jit_compile()\fP. Alternatively, \fBpcre2_code_copy()\fP or \fBpcre2_code_copy_with_tables()\fP can be used to obtain a private copy of the compiled code before calling the JIT compiler. @@ -1434,10 +1463,13 @@ letters in the subject. It is equivalent to Perl's /i option, and it can be changed within a pattern by a (?i) option setting. If either PCRE2_UTF or PCRE2_UCP is set, Unicode properties are used for all characters with more than one other case, and for all characters whose code points are greater than -U+007F. For lower valued characters with only one other case, a lookup table is -used for speed. When neither PCRE2_UTF nor PCRE2_UCP is set, a lookup table is -used for all code points less than 256, and higher code points (available only -in 16-bit or 32-bit mode) are treated as not having another case. +U+007F. Note that there are two ASCII characters, K and S, that, in addition to +their lower case ASCII equivalents, are case-equivalent with U+212A (Kelvin +sign) and U+017F (long S) respectively. For lower valued characters with only +one other case, a lookup table is used for speed. When neither PCRE2_UTF nor +PCRE2_UCP is set, a lookup table is used for all code points less than 256, and +higher code points (available only in 16-bit or 32-bit mode) are treated as not +having another case. .sp PCRE2_DOLLAR_ENDONLY .sp @@ -1843,6 +1875,13 @@ characters with code points greater than 127. .sp The option bits that can be set in a compile context by calling the \fBpcre2_set_compile_extra_options()\fP function are as follows: +.sp + PCRE2_EXTRA_ALLOW_LOOKAROUND_BSK +.sp +Since release 10.38 PCRE2 has forbidden the use of \eK within lookaround +assertions, following Perl's lead. This option is provided to re-enable the +previous behaviour (act in positive lookarounds, ignore in negative ones) in +case anybody is relying on it. .sp PCRE2_EXTRA_ALLOW_SURROGATE_ESCAPES .sp @@ -2458,19 +2497,27 @@ to an abstract format like Java or .NET serialization. Information about a successful or unsuccessful match is placed in a match data block, which is an opaque structure that is accessed by function calls. In particular, the match data block contains a vector of offsets into the subject -string that define the matched part of the subject and any substrings that were -captured. This is known as the \fIovector\fP. +string that define the matched parts of the subject. This is known as the +\fIovector\fP. .P Before calling \fBpcre2_match()\fP, \fBpcre2_dfa_match()\fP, or \fBpcre2_jit_match()\fP you must create a match data block by calling one of the creation functions above. For \fBpcre2_match_data_create()\fP, the first -argument is the number of pairs of offsets in the \fIovector\fP. One pair of -offsets is required to identify the string that matched the whole pattern, with -an additional pair for each captured substring. For example, a value of 4 -creates enough space to record the matched portion of the subject plus three -captured substrings. A minimum of at least 1 pair is imposed by -\fBpcre2_match_data_create()\fP, so it is always possible to return the overall -matched string. +argument is the number of pairs of offsets in the \fIovector\fP. +.P +When using \fBpcre2_match()\fP, one pair of offsets is required to identify the +string that matched the whole pattern, with an additional pair for each +captured substring. For example, a value of 4 creates enough space to record +the matched portion of the subject plus three captured substrings. +.P +When using \fBpcre2_dfa_match()\fP there may be multiple matched substrings of +different lengths at the same point in the subject. The ovector should be made +large enough to hold as many as are expected. +.P +A minimum of at least 1 pair is imposed by \fBpcre2_match_data_create()\fP, so +it is always possible to return the overall matched string in the case of +\fBpcre2_match()\fP or the longest match in the case of +\fBpcre2_dfa_match()\fP. .P The second argument of \fBpcre2_match_data_create()\fP is a pointer to a general context, which can specify custom memory management for obtaining the @@ -2479,10 +2526,11 @@ pass NULL, which causes \fBmalloc()\fP to be used. .P For \fBpcre2_match_data_create_from_pattern()\fP, the first argument is a pointer to a compiled pattern. The ovector is created to be exactly the right -size to hold all the substrings a pattern might capture. The second argument is -again a pointer to a general context, but in this case if NULL is passed, the -memory is obtained using the same allocator that was used for the compiled -pattern (custom or default). +size to hold all the substrings a pattern might capture when matched using +\fBpcre2_match()\fP. You should not use this call when matching with +\fBpcre2_dfa_match()\fP. The second argument is again a pointer to a general +context, but in this case if NULL is passed, the memory is obtained using the +same allocator that was used for the compiled pattern (custom or default). .P A match data block can be used many times, with the same or different compiled patterns. You can extract information from a match data block after a match @@ -2596,10 +2644,10 @@ lookbehind. For example, consider the pattern .sp which finds occurrences of "iss" in the middle of words. (\eB matches only if the current position in the subject is not a word boundary.) When applied to -the string "Mississipi" the first call to \fBpcre2_match()\fP finds the first +the string "Mississippi" the first call to \fBpcre2_match()\fP finds the first occurrence. If \fBpcre2_match()\fP is called again with just the remainder of -the subject, namely "issipi", it does not match, because \eB is always false at -the start of the subject, which is deemed to be a word boundary. However, if +the subject, namely "issippi", it does not match, because \eB is always false +at the start of the subject, which is deemed to be a word boundary. However, if \fBpcre2_match()\fP is passed the entire string again, but with \fIstartoffset\fP set to 4, it finds the second occurrence of "iss" because it is able to look behind the starting point to discover that it is preceded by a @@ -3959,7 +4007,7 @@ fail, this error is given. .sp .nf Philip Hazel -University Computing Service +Retired from University Computing Service Cambridge, England. .fi . @@ -3968,6 +4016,6 @@ Cambridge, England. .rs .sp .nf -Last updated: 19 March 2020 -Copyright (c) 1997-2020 University of Cambridge. +Last updated: 30 August 2021 +Copyright (c) 1997-2021 University of Cambridge. .fi diff --git a/pcre2/doc/pcre2build.3 b/pcre2/doc/pcre2build.3 index edea222..60931bf 100644 --- a/pcre2/doc/pcre2build.3 +++ b/pcre2/doc/pcre2build.3 @@ -563,15 +563,16 @@ documentation. .sp The C99 standard defines formatting modifiers z and t for size_t and ptrdiff_t values, respectively. By default, PCRE2 uses these modifiers in -environments other than Microsoft Visual Studio when __STDC_VERSION__ is -defined and has a value greater than or equal to 199901L (indicating C99). +environments other than old versions of Microsoft Visual Studio when +__STDC_VERSION__ is defined and has a value greater than or equal to 199901L +(indicating support for C99). However, there is at least one environment that claims to be C99 but does not support these modifiers. If .sp --disable-percent-zt .sp is specified, no use is made of the z or t modifiers. Instead of %td or %zu, -%lu is used, with a cast for size_t values. +a suitable format is used depending in the size of long for the platform. . . .SH "SUPPORT FOR FUZZERS" diff --git a/pcre2/doc/pcre2compat.3 b/pcre2/doc/pcre2compat.3 index b4209db..311d6eb 100644 --- a/pcre2/doc/pcre2compat.3 +++ b/pcre2/doc/pcre2compat.3 @@ -1,13 +1,13 @@ -.TH PCRE2COMPAT 3 "13 July 2019" "PCRE2 10.34" +.TH PCRE2COMPAT 3 "30 August 2021" "PCRE2 10.38" .SH NAME PCRE2 - Perl-compatible regular expressions (revised API) .SH "DIFFERENCES BETWEEN PCRE2 AND PERL" .rs .sp -This document describes the differences in the ways that PCRE2 and Perl handle -regular expressions. The differences described here are with respect to Perl -versions 5.26, but as both Perl and PCRE2 are continually changing, the -information may sometimes be out of date. +This document describes some of the differences in the ways that PCRE2 and Perl +handle regular expressions. The differences described here are with respect to +Perl version 5.32.0, but as both Perl and PCRE2 are continually changing, the +information may at times be out of date. .P 1. PCRE2 has only a subset of Perl's Unicode support. Details of what it does have are given in the @@ -21,11 +21,14 @@ they do not mean what you might think. For example, (?!a){3} does not assert that the next three characters are not "a". It just asserts that the next character is not "a" three times (in principle; PCRE2 optimizes this to run the assertion just once). Perl allows some repeat quantifiers on other assertions, -for example, \eb* (but not \eb{3}), but these do not seem to have any use. +for example, \eb* (but not \eb{3}, though oddly it does allow ^{3}), but these +do not seem to have any use. PCRE2 does not allow any kind of quantifier on +non-lookaround assertions. .P 3. Capture groups that occur inside negative lookaround assertions are counted, but their entries in the offsets vector are set only when a negative assertion is a condition that has a matching branch (that is, the condition is false). +Perl may set such capture groups in other circumstances. .P 4. The following Perl escape sequences are not supported: \eF, \el, \eL, \eu, \eU, and \eN when followed by a character name. \eN on its own, matching a @@ -41,10 +44,14 @@ interprets them. built with Unicode support (the default). The properties that can be tested with \ep and \eP are limited to the general category properties such as Lu and Nd, script names such as Greek or Han, and the derived properties Any and L&. -PCRE2 does support the Cs (surrogate) property, which Perl does not; the Perl -documentation says "Because Perl hides the need for the user to understand the -internal representation of Unicode characters, there is no need to implement -the somewhat messy concept of surrogates." +Both PCRE2 and Perl support the Cs (surrogate) property, but in PCRE2 its use +is limited. See the +.\" HREF +\fBpcre2pattern\fP +.\" +documentation for details. The long synonyms for property names that Perl +supports (such as \ep{Letter}) are not supported by PCRE2, nor is it permitted +to prefix any of these properties with "Is". .P 6. PCRE2 supports the \eQ...\eE escape for quoting substrings. Characters in between are treated as literals. However, this is slightly different from @@ -65,7 +72,8 @@ other character. Note the following examples: \eQA\eB\eE A\eB A\eB \eQ\e\eE \e \e\eE .sp -The \eQ...\eE sequence is recognized both inside and outside character classes. +The \eQ...\eE sequence is recognized both inside and outside character classes +by both PCRE2 and Perl. .P 7. Fairly obviously, PCRE2 does not support the (?{code}) and (??{code}) constructions. However, PCRE2 does have a "callout" feature, which allows an @@ -79,13 +87,13 @@ documentation for details. to PCRE2 release 10.23, but from release 10.30 this changed, and backtracking into subroutine calls is now supported, as in Perl. .P -9. If any of the backtracking control verbs are used in a group that is called -as a subroutine (whether or not recursively), their effect is confined to that -group; it does not extend to the surrounding pattern. This is not always the -case in Perl. In particular, if (*THEN) is present in a group that is called as -a subroutine, its action is limited to that group, even if the group does not -contain any | characters. Note that such groups are processed as anchored -at the point where they are tested. +9. In PCRE2, if any of the backtracking control verbs are used in a group that +is called as a subroutine (whether or not recursively), their effect is +confined to that group; it does not extend to the surrounding pattern. This is +not always the case in Perl. In particular, if (*THEN) is present in a group +that is called as a subroutine, its action is limited to that group, even if +the group does not contain any | characters. Note that such groups are +processed as anchored at the point where they are tested. .P 10. If a pattern contains more than one backtracking control verb, the first one that is backtracked onto acts. For example, in the pattern @@ -93,48 +101,51 @@ A(*COMMIT)B(*PRUNE)C a failure in B triggers (*COMMIT), but a failure in C triggers (*PRUNE). Perl's behaviour is more complex; in many cases it is the same as PCRE2, but there are cases where it differs. .P -11. Most backtracking verbs in assertions have their normal actions. They are -not confined to the assertion. -.P -12. There are some differences that are concerned with the settings of captured +11. There are some differences that are concerned with the settings of captured strings when part of a pattern is repeated. For example, matching "aba" against the pattern /^(a(b)?)+$/ in Perl leaves $2 unset, but in PCRE2 it is set to "b". .P -13. PCRE2's handling of duplicate capture group numbers and names is not as +12. PCRE2's handling of duplicate capture group numbers and names is not as general as Perl's. This is a consequence of the fact the PCRE2 works internally just with numbers, using an external table to translate between numbers and -names. In particular, a pattern such as (?|(?A)|(?B), where the two +names. In particular, a pattern such as (?|(?A)|(?B)), where the two capture groups have the same number but different names, is not supported, and causes an error at compile time. If it were allowed, it would not be possible to distinguish which group matched, because both names map to capture group number 1. To avoid this confusing situation, an error is given at compile time. .P -14. Perl used to recognize comments in some places that PCRE2 does not, for +13. Perl used to recognize comments in some places that PCRE2 does not, for example, between the ( and ? at the start of a group. If the /x modifier is set, Perl allowed white space between ( and ? though the latest Perls give an error (for a while it was just deprecated). There may still be some cases where Perl behaves differently. .P -15. Perl, when in warning mode, gives warnings for character classes such as +14. Perl, when in warning mode, gives warnings for character classes such as [A-\ed] or [a-[:digit:]]. It then treats the hyphens as literals. PCRE2 has no warning features, so it gives an error in these cases because they are almost certainly user mistakes. .P -16. In PCRE2, the upper/lower case character properties Lu and Ll are not +15. In PCRE2, the upper/lower case character properties Lu and Ll are not affected when case-independent matching is specified. For example, \ep{Lu} always matches an upper case letter. I think Perl has changed in this respect; -in the release at the time of writing (5.24), \ep{Lu} and \ep{Ll} match all +in the release at the time of writing (5.32), \ep{Lu} and \ep{Ll} match all letters, regardless of case, when case independence is specified. .P +16. From release 5.32.0, Perl locks out the use of \eK in lookaround +assertions. From release 10.38 PCRE2 does the same by default. However, there +is an option for re-enabling the previous behaviour. When this option is set, +\eK is acted on when it occurs in positive assertions, but is ignored in +negative assertions. +.P 17. PCRE2 provides some extensions to the Perl regular expression facilities. -Perl 5.10 includes new features that are not in earlier versions of Perl, some +Perl 5.10 included new features that were not in earlier versions of Perl, some of which (such as named parentheses) were in PCRE2 for some time before. This -list is with respect to Perl 5.26: +list is with respect to Perl 5.32: .sp (a) Although lookbehind assertions in PCRE2 must match fixed length strings, -each alternative branch of a lookbehind assertion can match a different length -of string. Perl requires them all to have the same length. +each alternative toplevel branch of a lookbehind assertion can match a +different length of string. Perl requires them all to have the same length. .sp (b) From PCRE2 10.23, backreferences to groups of fixed length are supported in lookbehinds, provided that there is no possibility of referencing a @@ -168,7 +179,7 @@ variable interpolation, but not general hooks on every match. different way and is not Perl-compatible. .sp (l) PCRE2 recognizes some special sequences such as (*CR) or (*NO_JIT) at -the start of a pattern that set overall options that cannot be changed within +the start of a pattern. These set overall options that cannot be changed within the pattern. .sp (m) PCRE2 supports non-atomic positive lookaround assertions. This is an @@ -194,7 +205,7 @@ fall into any stack-overflow limit. PCRE2 made a similar change at release .sp .nf Philip Hazel -University Computing Service +Retired from University Computing Service Cambridge, England. .fi . @@ -203,6 +214,6 @@ Cambridge, England. .rs .sp .nf -Last updated: 13 July 2019 -Copyright (c) 1997-2019 University of Cambridge. +Last updated: 30 August 2021 +Copyright (c) 1997-2021 University of Cambridge. .fi diff --git a/pcre2/doc/pcre2convert.3 b/pcre2/doc/pcre2convert.3 index 34beaf0..4ed6ea5 100644 --- a/pcre2/doc/pcre2convert.3 +++ b/pcre2/doc/pcre2convert.3 @@ -116,8 +116,8 @@ permitted to match separator characters, but the double-star (**) feature (which does match separators) is supported. .P PCRE2_CONVERT_GLOB_NO_WILD_SEPARATOR matches globs with wildcards allowed to -match separator characters. PCRE2_GLOB_NO_STARSTAR matches globs with the -double-star feature disabled. These options may be given together. +match separator characters. PCRE2_CONVERT_GLOB_NO_STARSTAR matches globs with +the double-star feature disabled. These options may be given together. . . .SH "CONVERTING POSIX PATTERNS" diff --git a/pcre2/doc/pcre2demo.3 b/pcre2/doc/pcre2demo.3 index 0d30145..57615a5 100644 --- a/pcre2/doc/pcre2demo.3 +++ b/pcre2/doc/pcre2demo.3 @@ -215,8 +215,8 @@ if (rc < 0) return 1; } -/* Match succeded. Get a pointer to the output vector, where string offsets are -stored. */ +/* Match succeeded. Get a pointer to the output vector, where string offsets +are stored. */ ovector = pcre2_get_ovector_pointer(match_data); printf("Match succeeded at offset %d\en", (int)ovector[0]); @@ -234,9 +234,12 @@ pcre2_match_data_create_from_pattern() above. */ if (rc == 0) printf("ovector was not big enough for all the captured substrings\en"); -/* We must guard against patterns such as /(?=.\eK)/ that use \eK in an assertion -to set the start of a match later than its end. In this demonstration program, -we just detect this case and give up. */ +/* Since release 10.38 PCRE2 has locked out the use of \eK in lookaround +assertions. However, there is an option to re-enable the old behaviour. If that +is set, it is possible to run patterns such as /(?=.\eK)/ that use \eK in an +assertion to set the start of a match later than its end. In this demonstration +program, we show how to detect this case, but it shouldn't arise because the +option is never set. */ if (ovector[0] > ovector[1]) { @@ -453,7 +456,7 @@ for (;;) return 1; } - /* Match succeded */ + /* Match succeeded */ printf("\enMatch succeeded again at offset %d\en", (int)ovector[0]); diff --git a/pcre2/doc/pcre2grep.1 b/pcre2/doc/pcre2grep.1 index 137117a..1081591 100644 --- a/pcre2/doc/pcre2grep.1 +++ b/pcre2/doc/pcre2grep.1 @@ -1,4 +1,4 @@ -.TH PCRE2GREP 1 "25 January 2020" "PCRE2 10.35" +.TH PCRE2GREP 1 "31 August 2021" "PCRE2 10.38" .SH NAME pcre2grep - a grep with Perl-compatible regular expressions. .SH SYNOPSIS @@ -79,8 +79,8 @@ matching substrings, or if \fB--only-matching\fP, \fB--file-offsets\fP, or (either shown literally, or as an offset), scanning resumes immediately following the match, so that further matches on the same line can be found. If there are multiple patterns, they are all tried on the remainder of the line, -but patterns that follow the one that matched are not tried on the earlier part -of the line. +but patterns that follow the one that matched are not tried on the earlier +matched part of the line. .P This behaviour means that the order in which multiple patterns are specified can affect the output when one of the above options is used. This is no longer @@ -115,11 +115,10 @@ ignored. .rs .sp By default, a file that contains a binary zero byte within the first 1024 bytes -is identified as a binary file, and is processed specially. (GNU grep -identifies binary files in this manner.) However, if the newline type is -specified as NUL, that is, the line terminator is a binary zero, the test for -a binary file is not applied. See the \fB--binary-files\fP option for a means -of changing the way binary files are handled. +is identified as a binary file, and is processed specially. However, if the +newline type is specified as NUL, that is, the line terminator is a binary +zero, the test for a binary file is not applied. See the \fB--binary-files\fP +option for a means of changing the way binary files are handled. . . .SH "BINARY ZEROS IN PATTERNS" @@ -158,6 +157,11 @@ is expected to be relatively small. When \fB-c\fP is used, \fB-A\fP is ignored. Treat binary files as text. This is equivalent to \fB--binary-files\fP=\fItext\fP. .TP +\fB--allow-lookaround-bsk\fP +PCRE2 now forbids the use of \eK in lookarounds by default, in line with Perl. +This option causes \fBpcre2grep\fP to set the PCRE2_EXTRA_ALLOW_LOOKAROUND_BSK +option, which enables this somewhat dangerous usage. +.TP \fB-B\fP \fInumber\fP, \fB--before-context=\fP\fInumber\fP Output up to \fInumber\fP lines of context before each matching line. Fewer lines are output if the previous match or the start of the file is within @@ -383,8 +387,8 @@ Ignore upper/lower case distinctions during comparisons. .TP \fB--include\fP=\fIpattern\fP If any \fB--include\fP patterns are specified, the only files that are -processed are those that match one of the patterns (and do not match an -\fB--exclude\fP pattern). This option does not affect directories, but it +processed are those whose names match one of the patterns and do not match an +\fB--exclude\fP pattern. This option does not affect directories, but it applies to all files, whether listed on the command line, obtained from \fB--file-list\fP, or by scanning a directory. The pattern is a PCRE2 regular expression, and is matched against the final component of the file name, not @@ -401,8 +405,8 @@ may be given any number of times; all the files are read. .TP \fB--include-dir\fP=\fIpattern\fP If any \fB--include-dir\fP patterns are specified, the only directories that -are processed are those that match one of the patterns (and do not match an -\fB--exclude-dir\fP pattern). This applies to all directories, whether listed +are processed are those whose names match one of the patterns and do not match +an \fB--exclude-dir\fP pattern. This applies to all directories, whether listed on the command line, obtained from \fB--file-list\fP, or by scanning a parent directory. The pattern is a PCRE2 regular expression, and is matched against the final component of the directory name, not the entire path. The \fB-F\fP, @@ -423,8 +427,9 @@ a separate line. Searching normally stops as soon as a matching line is found in a file. However, if the \fB-c\fP (count) option is also used, matching continues in order to obtain the correct count, and those files that have at least one match are listed along with their counts. Using this option with -\fB-c\fP is a way of suppressing the listing of files with no matches. This -opeion overrides any previous \fB-H\fP, \fB-h\fP, or \fB-L\fP options. +\fB-c\fP is a way of suppressing the listing of files with no matches that +occurs with \fB-c\fP on its own. This option overrides any previous \fB-H\fP, +\fB-h\fP, or \fB-L\fP options. .TP \fB--label\fP=\fIname\fP This option supplies a name to be used for the standard input when file names @@ -435,8 +440,8 @@ short form for this option. When this option is given, non-compressed input is read and processed line by line, and the output is flushed after each write. By default, input is read in large chunks, unless \fBpcre2grep\fP can determine that it is reading from a -terminal (which is currently possible only in Unix-like environments or -Windows). Output to terminal is normally automatically flushed by the operating +terminal, which is currently possible only in Unix-like environments or +Windows. Output to terminal is normally automatically flushed by the operating system. This option can be useful when the input or output is attached to a pipe and you do not want \fBpcre2grep\fP to buffer up large amounts of data. However, its use will affect performance, and the \fB-M\fP (multiline) option @@ -459,6 +464,45 @@ the value in the \fBLC_ALL\fP or \fBLC_CTYPE\fP environment variables. If no locale is specified, the PCRE2 library's default (usually the "C" locale) is used. There is no short form for this option. .TP +\fB-M\fP, \fB--multiline\fP +Allow patterns to match more than one line. When this option is set, the PCRE2 +library is called in "multiline" mode. This allows a matched string to extend +past the end of a line and continue on one or more subsequent lines. Patterns +used with \fB-M\fP may usefully contain literal newline characters and internal +occurrences of ^ and $ characters. The output for a successful match may +consist of more than one line. The first line is the line in which the match +started, and the last line is the line in which the match ended. If the matched +string ends with a newline sequence, the output ends at the end of that line. +If \fB-v\fP is set, none of the lines in a multi-line match are output. Once a +match has been handled, scanning restarts at the beginning of the line after +the one in which the match ended. +.sp +The newline sequence that separates multiple lines must be matched as part of +the pattern. For example, to find the phrase "regular expression" in a file +where "regular" might be at the end of a line and "expression" at the start of +the next line, you could use this command: +.sp + pcre2grep -M 'regular\es+expression' +.sp +The \es escape sequence matches any white space character, including newlines, +and is followed by + so as to match trailing white space on the first line as +well as possibly handling a two-character newline sequence. +.sp +There is a limit to the number of lines that can be matched, imposed by the way +that \fBpcre2grep\fP buffers the input file as it scans it. With a sufficiently +large processing buffer, this should not be a problem, but the \fB-M\fP option +does not work when input is read line by line (see \fB--line-buffered\fP.) +.TP +\fB-m\fP \fInumber\fP, \fB--max-count\fP=\fInumber\fP +Stop processing after finding \fInumber\fP matching lines, or non-matching +lines if \fB-v\fP is also set. Any trailing context lines are output after the +final match. In multiline mode, each multiline match counts as just one line +for this purpose. If this limit is reached when reading the standard input from +a regular file, the file is left positioned just after the last matching line. +If \fB-c\fP is also set, the count that is output is never greater than +\fInumber\fP. This option has no effect if used with \fB-L\fP, \fB-l\fP, or +\fB-q\fP, or when just checking for a match in a binary file. +.TP \fB--match-limit\fP=\fInumber\fP Processing some regular expression patterns may take a very long time to search for all possible matching strings. Others may require a very large amount of @@ -493,35 +537,6 @@ This limits the expansion of the processing buffer, whose initial size can be set by \fB--buffer-size\fP. The maximum buffer size is silently forced to be no smaller than the starting buffer size. .TP -\fB-M\fP, \fB--multiline\fP -Allow patterns to match more than one line. When this option is set, the PCRE2 -library is called in "multiline" mode. This allows a matched string to extend -past the end of a line and continue on one or more subsequent lines. Patterns -used with \fB-M\fP may usefully contain literal newline characters and internal -occurrences of ^ and $ characters. The output for a successful match may -consist of more than one line. The first line is the line in which the match -started, and the last line is the line in which the match ended. If the matched -string ends with a newline sequence, the output ends at the end of that line. -If \fB-v\fP is set, none of the lines in a multi-line match are output. Once a -match has been handled, scanning restarts at the beginning of the line after -the one in which the match ended. -.sp -The newline sequence that separates multiple lines must be matched as part of -the pattern. For example, to find the phrase "regular expression" in a file -where "regular" might be at the end of a line and "expression" at the start of -the next line, you could use this command: -.sp - pcre2grep -M 'regular\es+expression' -.sp -The \es escape sequence matches any white space character, including newlines, -and is followed by + so as to match trailing white space on the first line as -well as possibly handling a two-character newline sequence. -.sp -There is a limit to the number of lines that can be matched, imposed by the way -that \fBpcre2grep\fP buffers the input file as it scans it. With a sufficiently -large processing buffer, this should not be a problem, but the \fB-M\fP option -does not work when input is read line by line (see \fB--line-buffered\fP.) -.TP \fB-N\fP \fInewline-type\fP, \fB--newline\fP=\fInewline-type\fP Six different conventions for indicating the ends of lines in scanned files are supported. For example: @@ -565,27 +580,36 @@ use of JIT at run time. It is provided for testing and working round problems. It should never be needed in normal use. .TP \fB-O\fP \fItext\fP, \fB--output\fP=\fItext\fP -When there is a match, instead of outputting the whole line that matched, -output just the given text, followed by an operating-system standard newline. -The \fB--newline\fP option has no effect on this option, which is mutually -exclusive with \fB--only-matching\fP, \fB--file-offsets\fP, and -\fB--line-offsets\fP. Escape sequences starting with a dollar character may be -used to insert the contents of the matched part of the line and/or captured -substrings into the text. -.sp -$ or ${ } is replaced by the captured -substring of the given decimal number; zero substitutes the whole match. If -the number is greater than the number of capturing substrings, or if the -capture is unset, the replacement is empty. +When there is a match, instead of outputting the line that matched, output just +the text specified in this option, followed by an operating-system standard +newline. In this mode, no context is shown. That is, the \fB-A\fP, \fB-B\fP, +and \fB-C\fP options are ignored. The \fB--newline\fP option has no effect on +this option, which is mutually exclusive with \fB--only-matching\fP, +\fB--file-offsets\fP, and \fB--line-offsets\fP. However, like +\fB--only-matching\fP, if there is more than one match in a line, each of them +causes a line of output. +.sp +Escape sequences starting with a dollar character may be used to insert the +contents of the matched part of the line and/or captured substrings into the +text. +.sp +$ or ${ } is replaced by the captured substring of the given +decimal number; zero substitutes the whole match. If the number is greater than +the number of capturing substrings, or if the capture is unset, the replacement +is empty. .sp $a is replaced by bell; $b by backspace; $e by escape; $f by form feed; $n by newline; $r by carriage return; $t by tab; $v by vertical tab. .sp -$o is replaced by the character represented by the given octal -number; up to three digits are processed. +$o or $o{ } is replaced by the character whose code point is the +given octal number. In the first form, up to three octal digits are processed. +When more digits are needed in Unicode mode to specify a wide character, the +second form must be used. .sp -$x is replaced by the character represented by the given hexadecimal -number; up to two digits are processed. +$x or $x{ } is replaced by the character represented by the +given hexadecimal number. In the first form, up to two hexadecimal digits are +processed. When more digits are needed in Unicode mode to specify a wide +character, the second form must be used. .sp Any other character is substituted by itself. In particular, $$ is replaced by a single dollar. @@ -644,7 +668,8 @@ immediate end-of-file. This option is a shorthand for setting the \fB-d\fP option to "recurse". .TP \fB--recursion-limit\fP=\fInumber\fP -See \fB--match-limit\fP above. +This is an obsolete synonym for \fB--depth-limit\fP. See \fB--match-limit\fP +above for details. .TP \fB-s\fP, \fB--no-messages\fP Suppress error messages about non-existent or unreadable files. Such files are @@ -665,14 +690,17 @@ total would always be zero. \fB-u\fP, \fB--utf\fP Operate in UTF-8 mode. This option is available only if PCRE2 has been compiled with UTF-8 support. All patterns (including those for any \fB--exclude\fP and -\fB--include\fP options) and all subject lines that are scanned must be valid -strings of UTF-8 characters. +\fB--include\fP options) and all lines that are scanned must be valid strings +of UTF-8 characters. If an invalid UTF-8 string is encountered, an error +occurs. .TP \fB-U\fP, \fB--utf-allow-invalid\fP As \fB--utf\fP, but in addition subject lines may contain invalid UTF-8 code -unit sequences. These can never form part of any pattern match. This facility -allows valid UTF-8 strings to be sought in executable or other binary files. -For more details about matching in non-valid UTF-8 strings, see the +unit sequences. These can never form part of any pattern match. Patterns +themselves, however, must still be valid UTF-8 strings. This facility allows +valid UTF-8 strings to be sought within arbitrary byte sequences in executable +or other binary files. For more details about matching in non-valid UTF-8 +strings, see the .\" HREF \fBpcre2unicode\fP(3) .\" @@ -685,7 +713,9 @@ ignored. .TP \fB-v\fP, \fB--invert-match\fP Invert the sense of the match, so that lines which do \fInot\fP match any of -the patterns are the ones that are found. +the patterns are the ones that are found. When this option is set, options such +as \fB--only-matching\fP and \fB--output\fP, which specify parts of a match +that are to be output, are ignored. .TP \fB-w\fP, \fB--word-regex\fP, \fB--word-regexp\fP Force the patterns only to match "words". That is, there must be a word @@ -812,12 +842,36 @@ documentation for details). Numbered callouts are ignored by \fBpcre2grep\fP; only callouts with string arguments are useful. . . +.SS "Echoing a specific string" +.rs +.sp +Starting the callout string with a pipe character invokes an echoing facility +that avoids calling an external program or script. This facility is always +available, provided that callouts were not completely disabled when +\fBpcre2grep\fP was built. The rest of the callout string is processed as a +zero-terminated string, which means it should not contain any internal binary +zeros. It is written to the output, having first been passed through the same +escape processing as text from the \fB--output\fP (\fB-O\fP) option (see +above). However, $0 cannot be used to insert a matched substring because the +match is still in progress. Instead, the single character '0' is inserted. Any +syntax errors in the string (for example, a dollar not followed by another +character) causes the callout to be ignored. No terminator is added to the +output string, so if you want a newline, you must include it explicitly using +the escape $n. For example: +.sp + pcre2grep '(.)(..(.))(?C"|[$1] [$2] [$3]$n")' +.sp +Matching continues normally after the string is output. If you want to see only +the callout output but not any output from an actual match, you should end the +pattern with (*FAIL). +. +. .SS "Calling external programs or scripts" .rs .sp This facility can be independently disabled when \fBpcre2grep\fP is built. It is supported for Windows, where a call to \fB_spawnvp()\fP is used, for VMS, -where \fBlib$spawn()\fP is used, and for any other Unix-like environment where +where \fBlib$spawn()\fP is used, and for any Unix-like environment where \fBfork()\fP and \fBexecv()\fP are available. .P If the callout string does not start with a pipe (vertical bar) character, it @@ -828,13 +882,11 @@ arguments: executable_name|arg1|arg2|... .sp Any substring (including the executable name) may contain escape sequences -started by a dollar character: $ or ${ } is replaced by the -captured substring of the given decimal number, which must be greater than -zero. If the number is greater than the number of capturing substrings, or if -the capture is unset, the replacement is empty. -.P -Any other character is substituted by itself. In particular, $$ is replaced by -a single dollar and $| is replaced by a pipe character. Here is an example: +started by a dollar character. These are the same as for the \fB--output\fP +(\fB-O\fP) option documented above, except that $0 cannot insert the matched +string because the match is still in progress. Instead, the character '0' +is inserted. If you need a literal dollar or pipe character in any +substring, use $$ or $| respectively. Here is an example: .sp echo -e "abcde\en12345" | pcre2grep \e '(?x)(.)(..(.)) @@ -847,28 +899,14 @@ a single dollar and $| is replaced by a pipe character. Here is an example: Arg1: [1] [234] [4] Arg2: |1| () 12345 .sp -The parameters for the system call that is used to run the -program or script are zero-terminated strings. This means that binary zero -characters in the callout argument will cause premature termination of their -substrings, and therefore should not be present. Any syntax errors in the -string (for example, a dollar not followed by another character) cause the -callout to be ignored. If running the program fails for any reason (including -the non-existence of the executable), a local matching failure occurs and the -matcher backtracks in the normal way. -. -. -.SS "Echoing a specific string" -.rs -.sp -This facility is always available, provided that callouts were not completely -disabled when \fBpcre2grep\fP was built. If the callout string starts with a -pipe (vertical bar) character, the rest of the string is written to the output, -having been passed through the same escape processing as text from the --output -option. This provides a simple echoing facility that avoids calling an external -program or script. No terminator is added to the string, so if you want a -newline, you must include it explicitly. Matching continues normally after the -string is output. If you want to see only the callout output but not any output -from an actual match, you should end the relevant pattern with (*FAIL). +The parameters for the system call that is used to run the program or script +are zero-terminated strings. This means that binary zero characters in the +callout argument will cause premature termination of their substrings, and +therefore should not be present. Any syntax errors in the string (for example, +a dollar not followed by another character) causes the callout to be ignored. +If running the program fails for any reason (including the non-existence of the +executable), a local matching failure occurs and the matcher backtracks in the +normal way. . . .SH "MATCHING ERRORS" @@ -904,7 +942,8 @@ because VMS does not distinguish between exit(0) and exit(1). .SH "SEE ALSO" .rs .sp -\fBpcre2pattern\fP(3), \fBpcre2syntax\fP(3), \fBpcre2callout\fP(3). +\fBpcre2pattern\fP(3), \fBpcre2syntax\fP(3), \fBpcre2callout\fP(3), +\fBpcre2unicode\fP(3). . . .SH AUTHOR @@ -912,7 +951,7 @@ because VMS does not distinguish between exit(0) and exit(1). .sp .nf Philip Hazel -University Computing Service +Retired from University Computing Service Cambridge, England. .fi . @@ -921,6 +960,6 @@ Cambridge, England. .rs .sp .nf -Last updated: 25 January 2020 -Copyright (c) 1997-2020 University of Cambridge. +Last updated: 31 August 2021 +Copyright (c) 1997-2021 University of Cambridge. .fi diff --git a/pcre2/doc/pcre2grep.txt b/pcre2/doc/pcre2grep.txt index 4d41f54..8e9c757 100644 --- a/pcre2/doc/pcre2grep.txt +++ b/pcre2/doc/pcre2grep.txt @@ -80,7 +80,7 @@ DESCRIPTION following the match, so that further matches on the same line can be found. If there are multiple patterns, they are all tried on the re- mainder of the line, but patterns that follow the one that matched are - not tried on the earlier part of the line. + not tried on the earlier matched part of the line. This behaviour means that the order in which multiple patterns are specified can affect the output when one of the above options is used. @@ -115,10 +115,10 @@ BINARY FILES By default, a file that contains a binary zero byte within the first 1024 bytes is identified as a binary file, and is processed specially. - (GNU grep identifies binary files in this manner.) However, if the new- - line type is specified as NUL, that is, the line terminator is a binary - zero, the test for a binary file is not applied. See the --binary-files - option for a means of changing the way binary files are handled. + However, if the newline type is specified as NUL, that is, the line + terminator is a binary zero, the test for a binary file is not applied. + See the --binary-files option for a means of changing the way binary + files are handled. BINARY ZEROS IN PATTERNS @@ -158,110 +158,116 @@ OPTIONS Treat binary files as text. This is equivalent to --binary- files=text. + --allow-lookaround-bsk + PCRE2 now forbids the use of \K in lookarounds by default, in + line with Perl. This option causes pcre2grep to set the + PCRE2_EXTRA_ALLOW_LOOKAROUND_BSK option, which enables this + somewhat dangerous usage. + -B number, --before-context=number - Output up to number lines of context before each matching - line. Fewer lines are output if the previous match or the - start of the file is within number lines, or if the process- - ing buffer size has been set too small. If file names and/or + Output up to number lines of context before each matching + line. Fewer lines are output if the previous match or the + start of the file is within number lines, or if the process- + ing buffer size has been set too small. If file names and/or line numbers are being output, a hyphen separator is used in- - stead of a colon for the context lines. A line containing - "--" is output between each group of lines, unless they are - in fact contiguous in the input file. The value of number is - expected to be relatively small. When -c is used, -B is ig- + stead of a colon for the context lines. A line containing + "--" is output between each group of lines, unless they are + in fact contiguous in the input file. The value of number is + expected to be relatively small. When -c is used, -B is ig- nored. --binary-files=word - Specify how binary files are to be processed. If the word is - "binary" (the default), pattern matching is performed on bi- - nary files, but the only output is "Binary file - matches" when a match succeeds. If the word is "text", which - is equivalent to the -a or --text option, binary files are - processed in the same way as any other file. In this case, - when a match succeeds, the output may be binary garbage, - which can have nasty effects if sent to a terminal. If the - word is "without-match", which is equivalent to the -I op- + Specify how binary files are to be processed. If the word is + "binary" (the default), pattern matching is performed on bi- + nary files, but the only output is "Binary file + matches" when a match succeeds. If the word is "text", which + is equivalent to the -a or --text option, binary files are + processed in the same way as any other file. In this case, + when a match succeeds, the output may be binary garbage, + which can have nasty effects if sent to a terminal. If the + word is "without-match", which is equivalent to the -I op- tion, binary files are not processed at all; they are assumed - not to be of interest and are skipped without causing any + not to be of interest and are skipped without causing any output or affecting the return code. --buffer-size=number - Set the parameter that controls how much memory is obtained + Set the parameter that controls how much memory is obtained at the start of processing for buffering files that are being scanned. See also --max-buffer-size below. -C number, --context=number - Output number lines of context both before and after each - matching line. This is equivalent to setting both -A and -B + Output number lines of context both before and after each + matching line. This is equivalent to setting both -A and -B to the same value. -c, --count - Do not output lines from the files that are being scanned; - instead output the number of lines that would have been + Do not output lines from the files that are being scanned; + instead output the number of lines that would have been shown, either because they matched, or, if -v is set, because - they failed to match. By default, this count is exactly the - same as the number of lines that would have been output, but - if the -M (multiline) option is used (without -v), there may - be more suppressed lines than the count (that is, the number + they failed to match. By default, this count is exactly the + same as the number of lines that would have been output, but + if the -M (multiline) option is used (without -v), there may + be more suppressed lines than the count (that is, the number of matches). - If no lines are selected, the number zero is output. If sev- - eral files are are being scanned, a count is output for each - of them and the -t option can be used to cause a total to be - output at the end. However, if the --files-with-matches op- - tion is also used, only those files whose counts are greater + If no lines are selected, the number zero is output. If sev- + eral files are are being scanned, a count is output for each + of them and the -t option can be used to cause a total to be + output at the end. However, if the --files-with-matches op- + tion is also used, only those files whose counts are greater than zero are listed. When -c is used, the -A, -B, and -C op- tions are ignored. --colour, --color If this option is given without any data, it is equivalent to - "--colour=auto". If data is required, it must be given in + "--colour=auto". If data is required, it must be given in the same shell item, separated by an equals sign. --colour=value, --color=value This option specifies under what circumstances the parts of a line that matched a pattern should be coloured in the output. - By default, the output is not coloured. The value (which is - optional, see above) may be "never", "always", or "auto". In - the latter case, colouring happens only if the standard out- - put is connected to a terminal. More resources are used when + By default, the output is not coloured. The value (which is + optional, see above) may be "never", "always", or "auto". In + the latter case, colouring happens only if the standard out- + put is connected to a terminal. More resources are used when colouring is enabled, because pcre2grep has to search for all - possible matches in a line, not just one, in order to colour + possible matches in a line, not just one, in order to colour them all. - The colour that is used can be specified by setting one of - the environment variables PCRE2GREP_COLOUR, PCRE2GREP_COLOR, + The colour that is used can be specified by setting one of + the environment variables PCRE2GREP_COLOUR, PCRE2GREP_COLOR, PCREGREP_COLOUR, or PCREGREP_COLOR, which are checked in that order. If none of these are set, pcre2grep looks for - GREP_COLORS or GREP_COLOR (in that order). The value of the - variable should be a string of two numbers, separated by a - semicolon, except in the case of GREP_COLORS, which must + GREP_COLORS or GREP_COLOR (in that order). The value of the + variable should be a string of two numbers, separated by a + semicolon, except in the case of GREP_COLORS, which must start with "ms=" or "mt=" followed by two semicolon-separated - colours, terminated by the end of the string or by a colon. - If GREP_COLORS does not start with "ms=" or "mt=" it is ig- + colours, terminated by the end of the string or by a colon. + If GREP_COLORS does not start with "ms=" or "mt=" it is ig- nored, and GREP_COLOR is checked. - If the string obtained from one of the above variables con- + If the string obtained from one of the above variables con- tains any characters other than semicolon or digits, the set- ting is ignored and the default colour is used. The string is copied directly into the control string for setting colour on - a terminal, so it is your responsibility to ensure that the - values make sense. If no relevant environment variable is + a terminal, so it is your responsibility to ensure that the + values make sense. If no relevant environment variable is set, the default is "1;31", which gives red. -D action, --devices=action - If an input path is not a regular file or a directory, "ac- - tion" specifies how it is to be processed. Valid values are + If an input path is not a regular file or a directory, "ac- + tion" specifies how it is to be processed. Valid values are "read" (the default) or "skip" (silently skip the path). -d action, --directories=action If an input path is a directory, "action" specifies how it is - to be processed. Valid values are "read" (the default in - non-Windows environments, for compatibility with GNU grep), - "recurse" (equivalent to the -r option), or "skip" (silently - skip the path, the default in Windows environments). In the - "read" case, directories are read as if they were ordinary - files. In some operating systems the effect of reading a di- - rectory like this is an immediate end-of-file; in others it + to be processed. Valid values are "read" (the default in + non-Windows environments, for compatibility with GNU grep), + "recurse" (equivalent to the -r option), or "skip" (silently + skip the path, the default in Windows environments). In the + "read" case, directories are read as if they were ordinary + files. In some operating systems the effect of reading a di- + rectory like this is an immediate end-of-file; in others it may provoke an error. --depth-limit=number @@ -270,199 +276,200 @@ OPTIONS -e pattern, --regex=pattern, --regexp=pattern Specify a pattern to be matched. This option can be used mul- tiple times in order to specify several patterns. It can also - be used as a way of specifying a single pattern that starts - with a hyphen. When -e is used, no argument pattern is taken - from the command line; all arguments are treated as file - names. There is no limit to the number of patterns. They are - applied to each line in the order in which they are defined + be used as a way of specifying a single pattern that starts + with a hyphen. When -e is used, no argument pattern is taken + from the command line; all arguments are treated as file + names. There is no limit to the number of patterns. They are + applied to each line in the order in which they are defined until one matches. - If -f is used with -e, the command line patterns are matched + If -f is used with -e, the command line patterns are matched first, followed by the patterns from the file(s), independent - of the order in which these options are specified. Note that - multiple use of -e is not the same as a single pattern with + of the order in which these options are specified. Note that + multiple use of -e is not the same as a single pattern with alternatives. For example, X|Y finds the first character in a - line that is X or Y, whereas if the two patterns are given + line that is X or Y, whereas if the two patterns are given separately, with X first, pcre2grep finds X if it is present, even if it follows Y in the line. It finds Y only if there is - no X in the line. This matters only if you are using -o or + no X in the line. This matters only if you are using -o or --colo(u)r to show the part(s) of the line that matched. --exclude=pattern Files (but not directories) whose names match the pattern are - skipped without being processed. This applies to all files, - whether listed on the command line, obtained from --file- + skipped without being processed. This applies to all files, + whether listed on the command line, obtained from --file- list, or by scanning a directory. The pattern is a PCRE2 reg- - ular expression, and is matched against the final component + ular expression, and is matched against the final component of the file name, not the entire path. The -F, -w, and -x op- - tions do not apply to this pattern. The option may be given + tions do not apply to this pattern. The option may be given any number of times in order to specify multiple patterns. If - a file name matches both an --include and an --exclude pat- + a file name matches both an --include and an --exclude pat- tern, it is excluded. There is no short form for this option. --exclude-from=filename - Treat each non-empty line of the file as the data for an + Treat each non-empty line of the file as the data for an --exclude option. What constitutes a newline when reading the - file is the operating system's default. The --newline option - has no effect on this option. This option may be given more + file is the operating system's default. The --newline option + has no effect on this option. This option may be given more than once in order to specify a number of files to read. --exclude-dir=pattern Directories whose names match the pattern are skipped without - being processed, whatever the setting of the --recursive op- - tion. This applies to all directories, whether listed on the - command line, obtained from --file-list, or by scanning a - parent directory. The pattern is a PCRE2 regular expression, - and is matched against the final component of the directory - name, not the entire path. The -F, -w, and -x options do not - apply to this pattern. The option may be given any number of - times in order to specify more than one pattern. If a direc- - tory matches both --include-dir and --exclude-dir, it is ex- + being processed, whatever the setting of the --recursive op- + tion. This applies to all directories, whether listed on the + command line, obtained from --file-list, or by scanning a + parent directory. The pattern is a PCRE2 regular expression, + and is matched against the final component of the directory + name, not the entire path. The -F, -w, and -x options do not + apply to this pattern. The option may be given any number of + times in order to specify more than one pattern. If a direc- + tory matches both --include-dir and --exclude-dir, it is ex- cluded. There is no short form for this option. -F, --fixed-strings - Interpret each data-matching pattern as a list of fixed - strings, separated by newlines, instead of as a regular ex- + Interpret each data-matching pattern as a list of fixed + strings, separated by newlines, instead of as a regular ex- pression. What constitutes a newline for this purpose is con- trolled by the --newline option. The -w (match as a word) and - -x (match whole line) options can be used with -F. They ap- - ply to each of the fixed strings. A line is selected if any + -x (match whole line) options can be used with -F. They ap- + ply to each of the fixed strings. A line is selected if any of the fixed strings are found in it (subject to -w or -x, if - present). This option applies only to the patterns that are - matched against the contents of files; it does not apply to - patterns specified by any of the --include or --exclude op- + present). This option applies only to the patterns that are + matched against the contents of files; it does not apply to + patterns specified by any of the --include or --exclude op- tions. -f filename, --file=filename - Read patterns from the file, one per line, and match them - against each line of input. As is the case with patterns on - the command line, no delimiters should be used. What consti- - tutes a newline when reading the file is the operating sys- - tem's default interpretation of \n. The --newline option has - no effect on this option. Trailing white space is removed - from each line, and blank lines are ignored. An empty file - contains no patterns and therefore matches nothing. Patterns - read from a file in this way may contain binary zeros, which - are treated as ordinary data characters. See also the com- - ments about multiple patterns versus a single pattern with + Read patterns from the file, one per line, and match them + against each line of input. As is the case with patterns on + the command line, no delimiters should be used. What consti- + tutes a newline when reading the file is the operating sys- + tem's default interpretation of \n. The --newline option has + no effect on this option. Trailing white space is removed + from each line, and blank lines are ignored. An empty file + contains no patterns and therefore matches nothing. Patterns + read from a file in this way may contain binary zeros, which + are treated as ordinary data characters. See also the com- + ments about multiple patterns versus a single pattern with alternatives in the description of -e above. - If this option is given more than once, all the specified - files are read. A data line is output if any of the patterns - match it. A file name can be given as "-" to refer to the - standard input. When -f is used, patterns specified on the - command line using -e may also be present; they are tested - before the file's patterns. However, no other pattern is + If this option is given more than once, all the specified + files are read. A data line is output if any of the patterns + match it. A file name can be given as "-" to refer to the + standard input. When -f is used, patterns specified on the + command line using -e may also be present; they are tested + before the file's patterns. However, no other pattern is taken from the command line; all arguments are treated as the names of paths to be searched. --file-list=filename - Read a list of files and/or directories that are to be + Read a list of files and/or directories that are to be scanned from the given file, one per line. What constitutes a - newline when reading the file is the operating system's de- - fault. Trailing white space is removed from each line, and + newline when reading the file is the operating system's de- + fault. Trailing white space is removed from each line, and blank lines are ignored. These paths are processed before any - that are listed on the command line. The file name can be - given as "-" to refer to the standard input. If --file and - --file-list are both specified as "-", patterns are read - first. This is useful only when the standard input is a ter- - minal, from which further lines (the list of files) can be + that are listed on the command line. The file name can be + given as "-" to refer to the standard input. If --file and + --file-list are both specified as "-", patterns are read + first. This is useful only when the standard input is a ter- + minal, from which further lines (the list of files) can be read after an end-of-file indication. If this option is given more than once, all the specified files are read. --file-offsets - Instead of showing lines or parts of lines that match, show - each match as an offset from the start of the file and a - length, separated by a comma. In this mode, no context is - shown. That is, the -A, -B, and -C options are ignored. If + Instead of showing lines or parts of lines that match, show + each match as an offset from the start of the file and a + length, separated by a comma. In this mode, no context is + shown. That is, the -A, -B, and -C options are ignored. If there is more than one match in a line, each of them is shown - separately. This option is mutually exclusive with --output, + separately. This option is mutually exclusive with --output, --line-offsets, and --only-matching. -H, --with-filename - Force the inclusion of the file name at the start of output + Force the inclusion of the file name at the start of output lines when searching a single file. By default, the file name is not shown in this case. For matching lines, the file name is followed by a colon; for context lines, a hyphen separator - is used. If a line number is also being output, it follows - the file name. When the -M option causes a pattern to match - more than one line, only the first is preceded by the file - name. This option overrides any previous -h, -l, or -L op- + is used. If a line number is also being output, it follows + the file name. When the -M option causes a pattern to match + more than one line, only the first is preceded by the file + name. This option overrides any previous -h, -l, or -L op- tions. -h, --no-filename Suppress the output file names when searching multiple files. - By default, file names are shown when multiple files are - searched. For matching lines, the file name is followed by a - colon; for context lines, a hyphen separator is used. If a - line number is also being output, it follows the file name. + By default, file names are shown when multiple files are + searched. For matching lines, the file name is followed by a + colon; for context lines, a hyphen separator is used. If a + line number is also being output, it follows the file name. This option overrides any previous -H, -L, or -l options. --heap-limit=number See --match-limit below. - --help Output a help message, giving brief details of the command - options and file type support, and then exit. Anything else + --help Output a help message, giving brief details of the command + options and file type support, and then exit. Anything else on the command line is ignored. - -I Ignore binary files. This is equivalent to --binary- + -I Ignore binary files. This is equivalent to --binary- files=without-match. -i, --ignore-case Ignore upper/lower case distinctions during comparisons. --include=pattern - If any --include patterns are specified, the only files that - are processed are those that match one of the patterns (and - do not match an --exclude pattern). This option does not af- - fect directories, but it applies to all files, whether listed - on the command line, obtained from --file-list, or by scan- - ning a directory. The pattern is a PCRE2 regular expression, - and is matched against the final component of the file name, - not the entire path. The -F, -w, and -x options do not apply - to this pattern. The option may be given any number of times. - If a file name matches both an --include and an --exclude - pattern, it is excluded. There is no short form for this op- - tion. + If any --include patterns are specified, the only files that + are processed are those whose names match one of the patterns + and do not match an --exclude pattern. This option does not + affect directories, but it applies to all files, whether + listed on the command line, obtained from --file-list, or by + scanning a directory. The pattern is a PCRE2 regular expres- + sion, and is matched against the final component of the file + name, not the entire path. The -F, -w, and -x options do not + apply to this pattern. The option may be given any number of + times. If a file name matches both an --include and an --ex- + clude pattern, it is excluded. There is no short form for + this option. --include-from=filename - Treat each non-empty line of the file as the data for an + Treat each non-empty line of the file as the data for an --include option. What constitutes a newline for this purpose - is the operating system's default. The --newline option has + is the operating system's default. The --newline option has no effect on this option. This option may be given any number of times; all the files are read. --include-dir=pattern - If any --include-dir patterns are specified, the only direc- - tories that are processed are those that match one of the - patterns (and do not match an --exclude-dir pattern). This - applies to all directories, whether listed on the command - line, obtained from --file-list, or by scanning a parent di- - rectory. The pattern is a PCRE2 regular expression, and is - matched against the final component of the directory name, - not the entire path. The -F, -w, and -x options do not apply + If any --include-dir patterns are specified, the only direc- + tories that are processed are those whose names match one of + the patterns and do not match an --exclude-dir pattern. This + applies to all directories, whether listed on the command + line, obtained from --file-list, or by scanning a parent di- + rectory. The pattern is a PCRE2 regular expression, and is + matched against the final component of the directory name, + not the entire path. The -F, -w, and -x options do not apply to this pattern. The option may be given any number of times. - If a directory matches both --include-dir and --exclude-dir, + If a directory matches both --include-dir and --exclude-dir, it is excluded. There is no short form for this option. -L, --files-without-match - Instead of outputting lines from the files, just output the - names of the files that do not contain any lines that would - have been output. Each file name is output once, on a sepa- - rate line. This option overrides any previous -H, -h, or -l + Instead of outputting lines from the files, just output the + names of the files that do not contain any lines that would + have been output. Each file name is output once, on a sepa- + rate line. This option overrides any previous -H, -h, or -l options. -l, --files-with-matches - Instead of outputting lines from the files, just output the + Instead of outputting lines from the files, just output the names of the files containing lines that would have been out- - put. Each file name is output once, on a separate line. - Searching normally stops as soon as a matching line is found - in a file. However, if the -c (count) option is also used, - matching continues in order to obtain the correct count, and - those files that have at least one match are listed along + put. Each file name is output once, on a separate line. + Searching normally stops as soon as a matching line is found + in a file. However, if the -c (count) option is also used, + matching continues in order to obtain the correct count, and + those files that have at least one match are listed along with their counts. Using this option with -c is a way of sup- - pressing the listing of files with no matches. This opeion - overrides any previous -H, -h, or -L options. + pressing the listing of files with no matches that occurs + with -c on its own. This option overrides any previous -H, + -h, or -L options. --label=name This option supplies a name to be used for the standard input @@ -473,15 +480,15 @@ OPTIONS When this option is given, non-compressed input is read and processed line by line, and the output is flushed after each write. By default, input is read in large chunks, unless - pcre2grep can determine that it is reading from a terminal - (which is currently possible only in Unix-like environments - or Windows). Output to terminal is normally automatically - flushed by the operating system. This option can be useful - when the input or output is attached to a pipe and you do not - want pcre2grep to buffer up large amounts of data. However, - its use will affect performance, and the -M (multiline) op- - tion ceases to work. When input is from a compressed .gz or - .bz2 file, --line-buffered is ignored. + pcre2grep can determine that it is reading from a terminal, + which is currently possible only in Unix-like environments or + Windows. Output to terminal is normally automatically flushed + by the operating system. This option can be useful when the + input or output is attached to a pipe and you do not want + pcre2grep to buffer up large amounts of data. However, its + use will affect performance, and the -M (multiline) option + ceases to work. When input is from a compressed .gz or .bz2 + file, --line-buffered is ignored. --line-offsets Instead of showing lines or parts of lines that match, show @@ -501,138 +508,155 @@ OPTIONS brary's default (usually the "C" locale) is used. There is no short form for this option. + -M, --multiline + Allow patterns to match more than one line. When this option + is set, the PCRE2 library is called in "multiline" mode. This + allows a matched string to extend past the end of a line and + continue on one or more subsequent lines. Patterns used with + -M may usefully contain literal newline characters and inter- + nal occurrences of ^ and $ characters. The output for a suc- + cessful match may consist of more than one line. The first + line is the line in which the match started, and the last + line is the line in which the match ended. If the matched + string ends with a newline sequence, the output ends at the + end of that line. If -v is set, none of the lines in a + multi-line match are output. Once a match has been handled, + scanning restarts at the beginning of the line after the one + in which the match ended. + + The newline sequence that separates multiple lines must be + matched as part of the pattern. For example, to find the + phrase "regular expression" in a file where "regular" might + be at the end of a line and "expression" at the start of the + next line, you could use this command: + + pcre2grep -M 'regular\s+expression' + + The \s escape sequence matches any white space character, in- + cluding newlines, and is followed by + so as to match trail- + ing white space on the first line as well as possibly han- + dling a two-character newline sequence. + + There is a limit to the number of lines that can be matched, + imposed by the way that pcre2grep buffers the input file as + it scans it. With a sufficiently large processing buffer, + this should not be a problem, but the -M option does not work + when input is read line by line (see --line-buffered.) + + -m number, --max-count=number + Stop processing after finding number matching lines, or non- + matching lines if -v is also set. Any trailing context lines + are output after the final match. In multiline mode, each + multiline match counts as just one line for this purpose. If + this limit is reached when reading the standard input from a + regular file, the file is left positioned just after the last + matching line. If -c is also set, the count that is output + is never greater than number. This option has no effect if + used with -L, -l, or -q, or when just checking for a match in + a binary file. + --match-limit=number - Processing some regular expression patterns may take a very + Processing some regular expression patterns may take a very long time to search for all possible matching strings. Others - may require a very large amount of memory. There are three + may require a very large amount of memory. There are three options that set resource limits for matching. The --match-limit option provides a means of limiting comput- - ing resource usage when processing patterns that are not go- + ing resource usage when processing patterns that are not go- ing to match, but which have a very large number of possibil- ities in their search trees. The classic example is a pattern - that uses nested unlimited repeats. Internally, PCRE2 has a - counter that is incremented each time around its main pro- - cessing loop. If the value set by --match-limit is reached, + that uses nested unlimited repeats. Internally, PCRE2 has a + counter that is incremented each time around its main pro- + cessing loop. If the value set by --match-limit is reached, an error occurs. - The --heap-limit option specifies, as a number of kibibytes - (units of 1024 bytes), the amount of heap memory that may be + The --heap-limit option specifies, as a number of kibibytes + (units of 1024 bytes), the amount of heap memory that may be used for matching. Heap memory is needed only if matching the - pattern requires a significant number of nested backtracking + pattern requires a significant number of nested backtracking points to be remembered. This parameter can be set to zero to forbid the use of heap memory altogether. - The --depth-limit option limits the depth of nested back- + The --depth-limit option limits the depth of nested back- tracking points, which indirectly limits the amount of memory that is used. The amount of memory needed for each backtrack- - ing point depends on the number of capturing parentheses in + ing point depends on the number of capturing parentheses in the pattern, so the amount of memory that is used before this - limit acts varies from pattern to pattern. This limit is of + limit acts varies from pattern to pattern. This limit is of use only if it is set smaller than --match-limit. - There are no short forms for these options. The default lim- - its can be set when the PCRE2 library is compiled; if they - are not specified, the defaults are very large and so effec- + There are no short forms for these options. The default lim- + its can be set when the PCRE2 library is compiled; if they + are not specified, the defaults are very large and so effec- tively unlimited. --max-buffer-size=number - This limits the expansion of the processing buffer, whose - initial size can be set by --buffer-size. The maximum buffer - size is silently forced to be no smaller than the starting + This limits the expansion of the processing buffer, whose + initial size can be set by --buffer-size. The maximum buffer + size is silently forced to be no smaller than the starting buffer size. - -M, --multiline - Allow patterns to match more than one line. When this option - is set, the PCRE2 library is called in "multiline" mode. This - allows a matched string to extend past the end of a line and - continue on one or more subsequent lines. Patterns used with - -M may usefully contain literal newline characters and inter- - nal occurrences of ^ and $ characters. The output for a suc- - cessful match may consist of more than one line. The first - line is the line in which the match started, and the last - line is the line in which the match ended. If the matched - string ends with a newline sequence, the output ends at the - end of that line. If -v is set, none of the lines in a - multi-line match are output. Once a match has been handled, - scanning restarts at the beginning of the line after the one - in which the match ended. - - The newline sequence that separates multiple lines must be - matched as part of the pattern. For example, to find the - phrase "regular expression" in a file where "regular" might - be at the end of a line and "expression" at the start of the - next line, you could use this command: - - pcre2grep -M 'regular\s+expression' - - The \s escape sequence matches any white space character, in- - cluding newlines, and is followed by + so as to match trail- - ing white space on the first line as well as possibly han- - dling a two-character newline sequence. - - There is a limit to the number of lines that can be matched, - imposed by the way that pcre2grep buffers the input file as - it scans it. With a sufficiently large processing buffer, - this should not be a problem, but the -M option does not work - when input is read line by line (see --line-buffered.) - -N newline-type, --newline=newline-type Six different conventions for indicating the ends of lines in scanned files are supported. For example: pcre2grep -N CRLF 'some pattern' - The newline type may be specified in upper, lower, or mixed - case. If the newline type is NUL, lines are separated by bi- - nary zero characters. The other types are the single-charac- - ter sequences CR (carriage return) and LF (linefeed), the - two-character sequence CRLF, an "anycrlf" type, which recog- - nizes any of the preceding three types, and an "any" type, - for which any Unicode line ending sequence is assumed to end - a line. The Unicode sequences are the three just mentioned, - plus VT (vertical tab, U+000B), FF (form feed, U+000C), NEL - (next line, U+0085), LS (line separator, U+2028), and PS + The newline type may be specified in upper, lower, or mixed + case. If the newline type is NUL, lines are separated by bi- + nary zero characters. The other types are the single-charac- + ter sequences CR (carriage return) and LF (linefeed), the + two-character sequence CRLF, an "anycrlf" type, which recog- + nizes any of the preceding three types, and an "any" type, + for which any Unicode line ending sequence is assumed to end + a line. The Unicode sequences are the three just mentioned, + plus VT (vertical tab, U+000B), FF (form feed, U+000C), NEL + (next line, U+0085), LS (line separator, U+2028), and PS (paragraph separator, U+2029). - When the PCRE2 library is built, a default line-ending se- - quence is specified. This is normally the standard sequence - for the operating system. Unless otherwise specified by this + When the PCRE2 library is built, a default line-ending se- + quence is specified. This is normally the standard sequence + for the operating system. Unless otherwise specified by this option, pcre2grep uses the library's default. - This option makes it possible to use pcre2grep to scan files + This option makes it possible to use pcre2grep to scan files that have come from other environments without having to mod- - ify their line endings. If the data that is being scanned - does not agree with the convention set by this option, - pcre2grep may behave in strange ways. Note that this option - does not apply to files specified by the -f, --exclude-from, - or --include-from options, which are expected to use the op- + ify their line endings. If the data that is being scanned + does not agree with the convention set by this option, + pcre2grep may behave in strange ways. Note that this option + does not apply to files specified by the -f, --exclude-from, + or --include-from options, which are expected to use the op- erating system's standard newline sequence. -n, --line-number Precede each output line by its line number in the file, fol- - lowed by a colon for matching lines or a hyphen for context + lowed by a colon for matching lines or a hyphen for context lines. If the file name is also being output, it precedes the - line number. When the -M option causes a pattern to match - more than one line, only the first is preceded by its line + line number. When the -M option causes a pattern to match + more than one line, only the first is preceded by its line number. This option is forced if --line-offsets is used. - --no-jit If the PCRE2 library is built with support for just-in-time + --no-jit If the PCRE2 library is built with support for just-in-time compiling (which speeds up matching), pcre2grep automatically makes use of this, unless it was explicitly disabled at build - time. This option can be used to disable the use of JIT at - run time. It is provided for testing and working round prob- + time. This option can be used to disable the use of JIT at + run time. It is provided for testing and working round prob- lems. It should never be needed in normal use. -O text, --output=text - When there is a match, instead of outputting the whole line - that matched, output just the given text, followed by an op- - erating-system standard newline. The --newline option has no - effect on this option, which is mutually exclusive with - --only-matching, --file-offsets, and --line-offsets. Escape - sequences starting with a dollar character may be used to in- - sert the contents of the matched part of the line and/or cap- - tured substrings into the text. + When there is a match, instead of outputting the line that + matched, output just the text specified in this option, fol- + lowed by an operating-system standard newline. In this mode, + no context is shown. That is, the -A, -B, and -C options are + ignored. The --newline option has no effect on this option, + which is mutually exclusive with --only-matching, --file-off- + sets, and --line-offsets. However, like --only-matching, if + there is more than one match in a line, each of them causes a + line of output. + + Escape sequences starting with a dollar character may be used + to insert the contents of the matched part of the line and/or + captured substrings into the text. $ or ${ } is replaced by the captured sub- string of the given decimal number; zero substitutes the @@ -644,11 +668,17 @@ OPTIONS form feed; $n by newline; $r by carriage return; $t by tab; $v by vertical tab. - $o is replaced by the character represented by the - given octal number; up to three digits are processed. + $o or $o{ } is replaced by the character whose + code point is the given octal number. In the first form, up + to three octal digits are processed. When more digits are + needed in Unicode mode to specify a wide character, the sec- + ond form must be used. - $x is replaced by the character represented by the - given hexadecimal number; up to two digits are processed. + $x or $x{ } is replaced by the character rep- + resented by the given hexadecimal number. In the first form, + up to two hexadecimal digits are processed. When more digits + are needed in Unicode mode to specify a wide character, the + second form must be used. Any other character is substituted by itself. In particular, $$ is replaced by a single dollar. @@ -715,39 +745,41 @@ OPTIONS curse". --recursion-limit=number - See --match-limit above. + This is an obsolete synonym for --depth-limit. See --match- + limit above for details. -s, --no-messages - Suppress error messages about non-existent or unreadable - files. Such files are quietly skipped. However, the return + Suppress error messages about non-existent or unreadable + files. Such files are quietly skipped. However, the return code is still 2, even if matches were found in other files. -t, --total-count - This option is useful when scanning more than one file. If - used on its own, -t suppresses all output except for a grand - total number of matching lines (or non-matching lines if -v + This option is useful when scanning more than one file. If + used on its own, -t suppresses all output except for a grand + total number of matching lines (or non-matching lines if -v is used) in all the files. If -t is used with -c, a grand to- - tal is output except when the previous output is just one - line. In other words, it is not output when just one file's - count is listed. If file names are being output, the grand - total is preceded by "TOTAL:". Otherwise, it appears as just - another number. The -t option is ignored when used with -L - (list files without matches), because the grand total would + tal is output except when the previous output is just one + line. In other words, it is not output when just one file's + count is listed. If file names are being output, the grand + total is preceded by "TOTAL:". Otherwise, it appears as just + another number. The -t option is ignored when used with -L + (list files without matches), because the grand total would always be zero. -u, --utf Operate in UTF-8 mode. This option is available only if PCRE2 has been compiled with UTF-8 support. All patterns (including - those for any --exclude and --include options) and all sub- - ject lines that are scanned must be valid strings of UTF-8 - characters. + those for any --exclude and --include options) and all lines + that are scanned must be valid strings of UTF-8 characters. + If an invalid UTF-8 string is encountered, an error occurs. -U, --utf-allow-invalid - As --utf, but in addition subject lines may contain invalid - UTF-8 code unit sequences. These can never form part of any - pattern match. This facility allows valid UTF-8 strings to be - sought in executable or other binary files. For more details - about matching in non-valid UTF-8 strings, see the pcre2uni- - code(3) documentation. + As --utf, but in addition subject lines may contain invalid + UTF-8 code unit sequences. These can never form part of any + pattern match. Patterns themselves, however, must still be + valid UTF-8 strings. This facility allows valid UTF-8 strings + to be sought within arbitrary byte sequences in executable or + other binary files. For more details about matching in non- + valid UTF-8 strings, see the pcre2unicode(3) documentation. -V, --version Write the version numbers of pcre2grep and the PCRE2 library @@ -756,25 +788,28 @@ OPTIONS -v, --invert-match Invert the sense of the match, so that lines which do not - match any of the patterns are the ones that are found. + match any of the patterns are the ones that are found. When + this option is set, options such as --only-matching and + --output, which specify parts of a match that are to be out- + put, are ignored. -w, --word-regex, --word-regexp Force the patterns only to match "words". That is, there must - be a word boundary at the start and end of each matched - string. This is equivalent to having "\b(?:" at the start of - each pattern, and ")\b" at the end. This option applies only - to the patterns that are matched against the contents of - files; it does not apply to patterns specified by any of the + be a word boundary at the start and end of each matched + string. This is equivalent to having "\b(?:" at the start of + each pattern, and ")\b" at the end. This option applies only + to the patterns that are matched against the contents of + files; it does not apply to patterns specified by any of the --include or --exclude options. -x, --line-regex, --line-regexp - Force the patterns to start matching only at the beginnings - of lines, and in addition, require them to match entire + Force the patterns to start matching only at the beginnings + of lines, and in addition, require them to match entire lines. In multiline mode the match may be more than one line. This is equivalent to having "^(?:" at the start of each pat- - tern and ")$" at the end. This option applies only to the - patterns that are matched against the contents of files; it - does not apply to patterns specified by any of the --include + tern and ")$" at the end. This option applies only to the + patterns that are matched against the contents of files; it + does not apply to patterns specified by any of the --include or --exclude options. @@ -788,102 +823,125 @@ ENVIRONMENT VARIABLES NEWLINES - The -N (--newline) option allows pcre2grep to scan files with newline - conventions that differ from the default. This option affects only the - way scanned files are processed. It does not affect the interpretation - of files specified by the -f, --file-list, --exclude-from, or --in- + The -N (--newline) option allows pcre2grep to scan files with newline + conventions that differ from the default. This option affects only the + way scanned files are processed. It does not affect the interpretation + of files specified by the -f, --file-list, --exclude-from, or --in- clude-from options. - Any parts of the scanned input files that are written to the standard - output are copied with whatever newline sequences they have in the in- - put. However, if the final line of a file is output, and it does not - end with a newline sequence, a newline sequence is added. If the new- - line setting is CR, LF, CRLF or NUL, that line ending is output; for + Any parts of the scanned input files that are written to the standard + output are copied with whatever newline sequences they have in the in- + put. However, if the final line of a file is output, and it does not + end with a newline sequence, a newline sequence is added. If the new- + line setting is CR, LF, CRLF or NUL, that line ending is output; for the other settings (ANYCRLF or ANY) a single NL is used. - The newline setting does not affect the way in which pcre2grep writes - newlines in informational messages to the standard output and error - streams. Under Windows, the standard output is set to be binary, so - that "\r\n" at the ends of output lines that are copied from the input - is not converted to "\r\r\n" by the C I/O library. This means that any - messages written to the standard output must end with "\r\n". For all - other operating systems, and for all messages to the standard error + The newline setting does not affect the way in which pcre2grep writes + newlines in informational messages to the standard output and error + streams. Under Windows, the standard output is set to be binary, so + that "\r\n" at the ends of output lines that are copied from the input + is not converted to "\r\r\n" by the C I/O library. This means that any + messages written to the standard output must end with "\r\n". For all + other operating systems, and for all messages to the standard error stream, "\n" is used. OPTIONS COMPATIBILITY Many of the short and long forms of pcre2grep's options are the same as - in the GNU grep program. Any long option of the form --xxx-regexp (GNU + in the GNU grep program. Any long option of the form --xxx-regexp (GNU terminology) is also available as --xxx-regex (PCRE2 terminology). How- - ever, the --depth-limit, --file-list, --file-offsets, --heap-limit, - --include-dir, --line-offsets, --locale, --match-limit, -M, --multi- - line, -N, --newline, --om-separator, --output, -u, --utf, -U, and + ever, the --depth-limit, --file-list, --file-offsets, --heap-limit, + --include-dir, --line-offsets, --locale, --match-limit, -M, --multi- + line, -N, --newline, --om-separator, --output, -u, --utf, -U, and --utf-allow-invalid options are specific to pcre2grep, as is the use of the --only-matching option with a capturing parentheses number. - Although most of the common options work the same way, a few are dif- - ferent in pcre2grep. For example, the --include option's argument is a - glob for GNU grep, but a regular expression for pcre2grep. If both the - -c and -l options are given, GNU grep lists only file names, without + Although most of the common options work the same way, a few are dif- + ferent in pcre2grep. For example, the --include option's argument is a + glob for GNU grep, but a regular expression for pcre2grep. If both the + -c and -l options are given, GNU grep lists only file names, without counts, but pcre2grep gives the counts as well. OPTIONS WITH DATA There are four different ways in which an option with data can be spec- - ified. If a short form option is used, the data may follow immedi- + ified. If a short form option is used, the data may follow immedi- ately, or (with one exception) in the next command line item. For exam- ple: -f/some/file -f /some/file - The exception is the -o option, which may appear with or without data. - Because of this, if data is present, it must follow immediately in the + The exception is the -o option, which may appear with or without data. + Because of this, if data is present, it must follow immediately in the same item, for example -o3. - If a long form option is used, the data may appear in the same command - line item, separated by an equals character, or (with two exceptions) + If a long form option is used, the data may appear in the same command + line item, separated by an equals character, or (with two exceptions) it may appear in the next command line item. For example: --file=/some/file --file /some/file - Note, however, that if you want to supply a file name beginning with ~ - as data in a shell command, and have the shell expand ~ to a home di- - rectory, you must separate the file name from the option, because the + Note, however, that if you want to supply a file name beginning with ~ + as data in a shell command, and have the shell expand ~ to a home di- + rectory, you must separate the file name from the option, because the shell does not treat ~ specially unless it is at the start of an item. - The exceptions to the above are the --colour (or --color) and --only- - matching options, for which the data is optional. If one of these op- - tions does have data, it must be given in the first form, using an + The exceptions to the above are the --colour (or --color) and --only- + matching options, for which the data is optional. If one of these op- + tions does have data, it must be given in the first form, using an equals character. Otherwise pcre2grep will assume that it has no data. USING PCRE2'S CALLOUT FACILITY - pcre2grep has, by default, support for calling external programs or - scripts or echoing specific strings during matching by making use of - PCRE2's callout facility. However, this support can be completely or - partially disabled when pcre2grep is built. You can find out whether - your binary has support for callouts by running it with the --help op- - tion. If callout support is completely disabled, all callouts in pat- + pcre2grep has, by default, support for calling external programs or + scripts or echoing specific strings during matching by making use of + PCRE2's callout facility. However, this support can be completely or + partially disabled when pcre2grep is built. You can find out whether + your binary has support for callouts by running it with the --help op- + tion. If callout support is completely disabled, all callouts in pat- terns are ignored by pcre2grep. If the facility is partially disabled, - calling external programs is not supported, and callouts that request + calling external programs is not supported, and callouts that request it are ignored. - A callout in a PCRE2 pattern is of the form (?C ) where the argu- - ment is either a number or a quoted string (see the pcre2callout docu- - mentation for details). Numbered callouts are ignored by pcre2grep; + A callout in a PCRE2 pattern is of the form (?C ) where the argu- + ment is either a number or a quoted string (see the pcre2callout docu- + mentation for details). Numbered callouts are ignored by pcre2grep; only callouts with string arguments are useful. + Echoing a specific string + + Starting the callout string with a pipe character invokes an echoing + facility that avoids calling an external program or script. This facil- + ity is always available, provided that callouts were not completely + disabled when pcre2grep was built. The rest of the callout string is + processed as a zero-terminated string, which means it should not con- + tain any internal binary zeros. It is written to the output, having + first been passed through the same escape processing as text from the + --output (-O) option (see above). However, $0 cannot be used to insert + a matched substring because the match is still in progress. Instead, + the single character '0' is inserted. Any syntax errors in the string + (for example, a dollar not followed by another character) causes the + callout to be ignored. No terminator is added to the output string, so + if you want a newline, you must include it explicitly using the escape + $n. For example: + + pcre2grep '(.)(..(.))(?C"|[$1] [$2] [$3]$n")' + + Matching continues normally after the string is output. If you want to + see only the callout output but not any output from an actual match, + you should end the pattern with (*FAIL). + Calling external programs or scripts This facility can be independently disabled when pcre2grep is built. It is supported for Windows, where a call to _spawnvp() is used, for VMS, - where lib$spawn() is used, and for any other Unix-like environment - where fork() and execv() are available. + where lib$spawn() is used, and for any Unix-like environment where + fork() and execv() are available. If the callout string does not start with a pipe (vertical bar) charac- ter, it is parsed into a list of substrings separated by pipe charac- @@ -893,15 +951,11 @@ USING PCRE2'S CALLOUT FACILITY executable_name|arg1|arg2|... Any substring (including the executable name) may contain escape se- - quences started by a dollar character: $ or ${ } is re- - placed by the captured substring of the given decimal number, which - must be greater than zero. If the number is greater than the number of - capturing substrings, or if the capture is unset, the replacement is - empty. - - Any other character is substituted by itself. In particular, $$ is re- - placed by a single dollar and $| is replaced by a pipe character. Here - is an example: + quences started by a dollar character. These are the same as for the + --output (-O) option documented above, except that $0 cannot insert the + matched string because the match is still in progress. Instead, the + character '0' is inserted. If you need a literal dollar or pipe charac- + ter in any substring, use $$ or $| respectively. Here is an example: echo -e "abcde\n12345" | pcre2grep \ '(?x)(.)(..(.)) @@ -919,67 +973,54 @@ USING PCRE2'S CALLOUT FACILITY ters in the callout argument will cause premature termination of their substrings, and therefore should not be present. Any syntax errors in the string (for example, a dollar not followed by another character) - cause the callout to be ignored. If running the program fails for any + causes the callout to be ignored. If running the program fails for any reason (including the non-existence of the executable), a local match- ing failure occurs and the matcher backtracks in the normal way. - Echoing a specific string - - This facility is always available, provided that callouts were not com- - pletely disabled when pcre2grep was built. If the callout string starts - with a pipe (vertical bar) character, the rest of the string is written - to the output, having been passed through the same escape processing as - text from the --output option. This provides a simple echoing facility - that avoids calling an external program or script. No terminator is - added to the string, so if you want a newline, you must include it ex- - plicitly. Matching continues normally after the string is output. If - you want to see only the callout output but not any output from an ac- - tual match, you should end the relevant pattern with (*FAIL). - MATCHING ERRORS - It is possible to supply a regular expression that takes a very long - time to fail to match certain lines. Such patterns normally involve - nested indefinite repeats, for example: (a+)*\d when matched against a - line of a's with no final digit. The PCRE2 matching function has a re- - source limit that causes it to abort in these circumstances. If this - happens, pcre2grep outputs an error message and the line that caused - the problem to the standard error stream. If there are more than 20 + It is possible to supply a regular expression that takes a very long + time to fail to match certain lines. Such patterns normally involve + nested indefinite repeats, for example: (a+)*\d when matched against a + line of a's with no final digit. The PCRE2 matching function has a re- + source limit that causes it to abort in these circumstances. If this + happens, pcre2grep outputs an error message and the line that caused + the problem to the standard error stream. If there are more than 20 such errors, pcre2grep gives up. - The --match-limit option of pcre2grep can be used to set the overall - resource limit. There are also other limits that affect the amount of - memory used during matching; see the discussion of --heap-limit and + The --match-limit option of pcre2grep can be used to set the overall + resource limit. There are also other limits that affect the amount of + memory used during matching; see the discussion of --heap-limit and --depth-limit above. DIAGNOSTICS Exit status is 0 if any matches were found, 1 if no matches were found, - and 2 for syntax errors, overlong lines, non-existent or inaccessible - files (even if matches were found in other files) or too many matching + and 2 for syntax errors, overlong lines, non-existent or inaccessible + files (even if matches were found in other files) or too many matching errors. Using the -s option to suppress error messages about inaccessi- ble files does not affect the return code. - When run under VMS, the return code is placed in the symbol - PCRE2GREP_RC because VMS does not distinguish between exit(0) and + When run under VMS, the return code is placed in the symbol + PCRE2GREP_RC because VMS does not distinguish between exit(0) and exit(1). SEE ALSO - pcre2pattern(3), pcre2syntax(3), pcre2callout(3). + pcre2pattern(3), pcre2syntax(3), pcre2callout(3), pcre2unicode(3). AUTHOR Philip Hazel - University Computing Service + Retired from University Computing Service Cambridge, England. REVISION - Last updated: 25 January 2020 - Copyright (c) 1997-2020 University of Cambridge. + Last updated: 31 August 2021 + Copyright (c) 1997-2021 University of Cambridge. diff --git a/pcre2/doc/pcre2jit.3 b/pcre2/doc/pcre2jit.3 index fab8366..9b77550 100644 --- a/pcre2/doc/pcre2jit.3 +++ b/pcre2/doc/pcre2jit.3 @@ -29,6 +29,7 @@ platforms: .sp ARM 32-bit (v5, v7, and Thumb2) ARM 64-bit + IBM s390x 64 bit Intel x86 32-bit and 64-bit MIPS 32-bit and 64-bit Power PC 32-bit and 64-bit @@ -266,7 +267,7 @@ inefficient solution, and not recommended. This is a suggestion for how a multithreaded program that needs to set up non-default JIT stacks might operate: .sp - During thread initalization + During thread initialization thread_local_var = pcre2_jit_stack_create(...) .sp During thread exit diff --git a/pcre2/doc/pcre2matching.3 b/pcre2/doc/pcre2matching.3 index 7f9bbac..673952d 100644 --- a/pcre2/doc/pcre2matching.3 +++ b/pcre2/doc/pcre2matching.3 @@ -1,4 +1,4 @@ -.TH PCRE2MATCHING 3 "23 May 2019" "PCRE2 10.34" +.TH PCRE2MATCHING 3 "28 August 2021" "PCRE2 10.38" .SH NAME PCRE2 - Perl-compatible regular expressions (revised API) .SH "PCRE2 MATCHING ALGORITHMS" @@ -61,8 +61,9 @@ tried is controlled by the greedy or ungreedy nature of the quantifier. If a leaf node is reached, a matching string has been found, and at that point the algorithm stops. Thus, if there is more than one possible match, this algorithm returns the first one that it finds. Whether this is the shortest, -the longest, or some intermediate length depends on the way the greedy and -ungreedy repetition quantifiers are specified in the pattern. +the longest, or some intermediate length depends on the way the alternations +and the greedy or ungreedy repetition quantifiers are specified in the +pattern. .P Because it ends up with a single path through the tree, it is relatively straightforward for this algorithm to keep track of the substrings that are @@ -91,10 +92,15 @@ no more unterminated paths. At this point, terminated paths represent the different matching possibilities (if there are none, the match has failed). Thus, if there is more than one possible match, this algorithm finds all of them, and in particular, it finds the longest. The matches are returned in -decreasing order of length. There is an option to stop the algorithm after the -first match (which is necessarily the shortest) is found. +the output vector in decreasing order of length. There is an option to stop the +algorithm after the first match (which is necessarily the shortest) is found. .P -Note that all the matches that are found start at the same point in the +Note that the size of vector needed to contain all the results depends on the +number of simultaneous matches, not on the number of parentheses in the +pattern. Using \fBpcre2_match_data_create_from_pattern()\fP to create the match +data block is therefore not advisable when doing DFA matching. +.P +Note also that all the matches that are found start at the same point in the subject. If the pattern .sp cat(er(pillar)?)? @@ -165,19 +171,13 @@ supported by \fBpcre2_dfa_match()\fP. .SH "ADVANTAGES OF THE ALTERNATIVE ALGORITHM" .rs .sp -Using the alternative matching algorithm provides the following advantages: -.P -1. All possible matches (at a single point in the subject) are automatically -found, and in particular, the longest match is found. To find more than one -match using the standard algorithm, you have to do kludgy things with -callouts. +The main advantage of the alternative algorithm is that all possible matches +(at a single point in the subject) are automatically found, and in particular, +the longest match is found. To find more than one match at the same point using +the standard algorithm, you have to do kludgy things with callouts. .P -2. Because the alternative algorithm scans the subject string just once, and -never needs to backtrack (except for lookbehinds), it is possible to pass very -long subject strings to the matching function in several pieces, checking for -partial matching each time. Although it is also possible to do multi-segment -matching using the standard algorithm, by retaining partially matched -substrings, it is more complicated. The +Partial matching is possible with this algorithm, though it has some +limitations. The .\" HREF \fBpcre2partial\fP .\" @@ -199,6 +199,8 @@ invalid UTF string are not supported. .P 3. Although atomic groups are supported, their use does not provide the performance advantage that it does for the standard algorithm. +.P +4. JIT optimization is not supported. . . .SH AUTHOR @@ -206,7 +208,7 @@ performance advantage that it does for the standard algorithm. .sp .nf Philip Hazel -University Computing Service +Retired from University Computing Service Cambridge, England. .fi . @@ -215,6 +217,6 @@ Cambridge, England. .rs .sp .nf -Last updated: 23 May 2019 -Copyright (c) 1997-2019 University of Cambridge. +Last updated: 28 August 2021 +Copyright (c) 1997-2021 University of Cambridge. .fi diff --git a/pcre2/doc/pcre2pattern.3 b/pcre2/doc/pcre2pattern.3 index c88ce03..627f229 100644 --- a/pcre2/doc/pcre2pattern.3 +++ b/pcre2/doc/pcre2pattern.3 @@ -1,4 +1,4 @@ -.TH PCRE2PATTERN 3 "24 February 2020" "PCRE2 10.35" +.TH PCRE2PATTERN 3 "3o0 August 2021" "PCRE2 10.38" .SH NAME PCRE2 - Perl-compatible regular expressions (revised API) .SH "PCRE2 REGULAR EXPRESSION DETAILS" @@ -263,8 +263,11 @@ corresponding characters in the subject. As a trivial example, the pattern The quick brown fox .sp matches a portion of a subject string that is identical to itself. When -caseless matching is specified (the PCRE2_CASELESS option), letters are matched -independently of case. +caseless matching is specified (the PCRE2_CASELESS option or (?i) within the +pattern), letters are matched independently of case. Note that there are two +ASCII characters, K and S, that, in addition to their lower case ASCII +equivalents, are case-equivalent with Unicode U+212A (Kelvin sign) and U+017F +(long S) respectively when either PCRE2_UTF or PCRE2_UCP is set. .P The power of regular expressions comes from the ability to include wild cards, character classes, alternatives, and repetitions in the pattern. These are @@ -298,6 +301,22 @@ a character class the only metacharacters are: [ POSIX character class (if followed by POSIX syntax) ] terminates the character class .sp +If a pattern is compiled with the PCRE2_EXTENDED option, most white space in +the pattern, other than in a character class, and characters between a # +outside a character class and the next newline, inclusive, are ignored. An +escaping backslash can be used to include a white space or a # character as +part of the pattern. If the PCRE2_EXTENDED_MORE option is set, the same +applies, but in addition unescaped space and horizontal tab characters are +ignored inside a character class. Note: only these two characters are ignored, +not the full set of pattern white space characters that are ignored outside a +character class. Option settings can be changed within a pattern; see the +section entitled +.\" HTML +.\" +"Internal Option Setting" +.\" +below. +.P The following sections describe the use of each of the metacharacters. . . @@ -315,15 +334,9 @@ would otherwise be interpreted as a metacharacter, so it is always safe to precede a non-alphanumeric with backslash to specify that it stands for itself. In particular, if you want to match a backslash, you write \e\e. .P -In a UTF mode, only ASCII digits and letters have any special meaning after a -backslash. All other characters (in particular, those whose code points are -greater than 127) are treated as literals. -.P -If a pattern is compiled with the PCRE2_EXTENDED option, most white space in -the pattern (other than in a character class), and characters between a # -outside a character class and the next newline, inclusive, are ignored. An -escaping backslash can be used to include a white space or # character as part -of the pattern. +Only ASCII digits and letters have any special meaning after a backslash. All +other characters (in particular, those whose code points are greater than 127) +are treated as literals. .P If you want to treat all characters in a sequence as literals, you can do so by putting them between \eQ and \eE. This is different from Perl in that $ and @ @@ -728,7 +741,7 @@ Unicode support is not needed for these characters to be recognized. .P It is possible to restrict \eR to match only CR, LF, or CRLF (instead of the complete set of Unicode line endings) by setting the option PCRE2_BSR_ANYCRLF -at compile time. (BSR is an abbrevation for "backslash R".) This can be made +at compile time. (BSR is an abbreviation for "backslash R".) This can be made the default when PCRE2 is built; if this is the case, the other behaviour can be requested via the PCRE2_BSR_UNICODE option. It is also possible to specify these settings by starting a pattern string with one of the following @@ -819,6 +832,7 @@ Common, Coptic, Cuneiform, Cypriot, +Cypro_Minoan, Cyrillic, Deseret, Devanagari, @@ -902,6 +916,7 @@ Old_Persian, Old_Sogdian, Old_South_Arabian, Old_Turkic, +Old_Uyghur, Oriya, Osage, Osmanya, @@ -933,6 +948,7 @@ Tai_Tham, Tai_Viet, Takri, Tamil, +Tangsa, Tangut, Telugu, Thaana, @@ -940,9 +956,11 @@ Thai, Tibetan, Tifinagh, Tirhuta, +Toto, Ugaritic, Unknown, Vai, +Vithkuqi, Wancho, Warang_Citi, Yezidi, @@ -1069,7 +1087,7 @@ additional characters according to the following rules for ending a cluster: 3. Do not break Hangul (a Korean script) syllable sequences. Hangul characters are of five types: L, V, T, LV, and LVT. An L character may be followed by an L, V, LV, or LVT character; an LV or V character may be followed by a V or T -character; an LVT or T character may be follwed only by a T character. +character; an LVT or T character may be followed only by a T character. .P 4. Do not end before extending characters or spacing marks or the "zero-width joiner" character. Characters with the "mark" property always have the @@ -1155,8 +1173,11 @@ For example, when the pattern .sp matches "foobar", the first substring is still set to "foo". .P -Perl documents that the use of \eK within assertions is "not well defined". In -PCRE2, \eK is acted upon when it occurs inside positive assertions, but is +From version 5.32.0 Perl forbids the use of \eK in lookaround assertions. From +release 10.38 PCRE2 also forbids this by default. However, the +PCRE2_EXTRA_ALLOW_LOOKAROUND_BSK option can be used when calling +\fBpcre2_compile()\fP to re-enable the previous behaviour. When this option is +set, \eK is acted upon when it occurs inside positive assertions, but is ignored in negative assertions. Note that when a pattern such as (?=ab\eK) matches, the reported start of the match can be greater than the end of the match. Using \eK in a lookbehind assertion at the start of a pattern can also @@ -1436,7 +1457,10 @@ Characters in a class may be specified by their code points using \eo, \ex, or \eN{U+hh..} in the usual way. When caseless matching is set, any letters in a class represent both their upper case and lower case versions, so for example, a caseless [aeiou] matches "A" as well as "a", and a caseless [^aeiou] does not -match "A", whereas a caseful version would. +match "A", whereas a caseful version would. Note that there are two ASCII +characters, K and S, that, in addition to their lower case ASCII equivalents, +are case-equivalent with Unicode U+212A (Kelvin sign) and U+017F (long S) +respectively when either PCRE2_UTF or PCRE2_UCP is set. .P Characters that might indicate line breaks are never treated in any special way when matching character classes, whatever line-ending sequence is in use, and @@ -2911,7 +2935,7 @@ breaks): (?(DEFINE) (? 2[0-4]\ed | 25[0-5] | 1\ed\ed | [1-9]?\ed) ) \eb (?&byte) (\e.(?&byte)){3} \eb .sp -The first part of the pattern is a DEFINE group inside which a another group +The first part of the pattern is a DEFINE group inside which another group named "byte" is defined. This matches an individual component of an IPv4 address (a number less than 256). When matching takes place, this part of the pattern is skipped because DEFINE acts like a false condition. The rest of the @@ -3641,7 +3665,7 @@ successful match if there is a later mismatch. Consider: .sp If the subject is "aaaac...", after the first match attempt fails (starting at the first character in the string), the starting point skips on to start the -next attempt at "c". Note that a possessive quantifer does not have the same +next attempt at "c". Note that a possessive quantifier does not have the same effect as this example; although it would suppress backtracking during the first match attempt, the second attempt would start at the second character instead of skipping on to "c". @@ -3872,7 +3896,7 @@ there is a backtrack at the outer level. .sp .nf Philip Hazel -University Computing Service +Retired from University Computing Service Cambridge, England. .fi . @@ -3881,6 +3905,6 @@ Cambridge, England. .rs .sp .nf -Last updated: 24 February 2020 -Copyright (c) 1997-2020 University of Cambridge. +Last updated: 30 August 2021 +Copyright (c) 1997-2021 University of Cambridge. .fi diff --git a/pcre2/doc/pcre2posix.3 b/pcre2/doc/pcre2posix.3 index 35e68e2..6cfede7 100644 --- a/pcre2/doc/pcre2posix.3 +++ b/pcre2/doc/pcre2posix.3 @@ -1,4 +1,4 @@ -.TH PCRE2POSIX 3 "30 January 2019" "PCRE2 10.33" +.TH PCRE2POSIX 3 "26 April 2021" "PCRE2 10.37" .SH NAME PCRE2 - Perl-compatible regular expressions (revised API) .SH "SYNOPSIS" @@ -44,11 +44,14 @@ can be accessed by adding \fB-lpcre2-posix\fP to the command for linking an application. Because the POSIX functions call the native ones, it is also necessary to add \fB-lpcre2-8\fP. .P -Although they are not defined as protypes in \fBpcre2posix.h\fP, the library -does contain functions with the POSIX names \fBregcomp()\fP etc. These simply -pass their arguments to the PCRE2 functions. These functions are provided for -backwards compatibility with earlier versions of PCRE2, so that existing -programs do not have to be recompiled. +Although they were not defined as protypes in \fBpcre2posix.h\fP, releases +10.33 to 10.36 of the library contained functions with the POSIX names +\fBregcomp()\fP etc. These simply passed their arguments to the PCRE2 +functions. These functions were provided for backwards compatibility with +earlier versions of PCRE2, which had only POSIX names. However, this has proved +troublesome in situations where a program links with several libraries, some of +which use PCRE2's POSIX interface while others use the real POSIX functions. +For this reason, the POSIX names have been removed since release 10.37. .P Calling the header file \fBpcre2posix.h\fP avoids any conflict with other POSIX libraries. It can, of course, be renamed or aliased as \fBregex.h\fP, which is @@ -321,6 +324,6 @@ Cambridge, England. .rs .sp .nf -Last updated: 30 January 2019 -Copyright (c) 1997-2019 University of Cambridge. +Last updated: 26 April 2021 +Copyright (c) 1997-2021 University of Cambridge. .fi diff --git a/pcre2/doc/pcre2syntax.3 b/pcre2/doc/pcre2syntax.3 index 7076462..937c817 100644 --- a/pcre2/doc/pcre2syntax.3 +++ b/pcre2/doc/pcre2syntax.3 @@ -1,4 +1,4 @@ -.TH PCRE2SYNTAX 3 "28 December 2019" "PCRE2 10.35" +.TH PCRE2SYNTAX 3 "30 August 2021" "PCRE2 10.38" .SH NAME PCRE2 - Perl-compatible regular expressions (revised API) .SH "PCRE2 REGULAR EXPRESSION SYNTAX SUMMARY" @@ -198,6 +198,7 @@ Common, Coptic, Cuneiform, Cypriot, +Cypro_Minoan, Cyrillic, Deseret, Devanagari, @@ -281,6 +282,7 @@ Old_Persian, Old_Sogdian, Old_South_Arabian, Old_Turkic, +Old_Uyghur, Oriya, Osage, Osmanya, @@ -312,6 +314,7 @@ Tai_Tham, Tai_Viet, Takri, Tamil, +Tangsa, Tangut, Telugu, Thaana, @@ -319,8 +322,10 @@ Thai, Tibetan, Tifinagh, Tirhuta, +Toto, Ugaritic, Vai, +Vithkuqi, Wancho, Warang_Citi, Yezidi, @@ -401,6 +406,9 @@ but some of them use Unicode properties if PCRE2_UCP is set. You can use .sp \eK set reported start of match .sp +From release 10.38 \eK is not permitted by default in lookaround assertions, +for compatibility with Perl. However, if the PCRE2_EXTRA_ALLOW_LOOKAROUND_BSK +option is set, the previous behaviour is re-enabled. When this option is set, \eK is honoured in positive assertions, but ignored in negative ones. . . @@ -667,7 +675,7 @@ delimiter }. To encode the ending delimiter within the string, double it. .sp .nf Philip Hazel -University Computing Service +Retired from University Computing Service Cambridge, England. .fi . @@ -676,6 +684,6 @@ Cambridge, England. .rs .sp .nf -Last updated: 28 December 2019 -Copyright (c) 1997-2019 University of Cambridge. +Last updated: 30 August 2021 +Copyright (c) 1997-2021 University of Cambridge. .fi diff --git a/pcre2/doc/pcre2test.1 b/pcre2/doc/pcre2test.1 index ec17763..d98e974 100644 --- a/pcre2/doc/pcre2test.1 +++ b/pcre2/doc/pcre2test.1 @@ -1,4 +1,4 @@ -.TH PCRE2TEST 1 "20 March 2020" "PCRE 10.35" +.TH PCRE2TEST 1 "30 August 2021" "PCRE 10.38" .SH NAME pcre2test - a program for testing Perl-compatible regular expressions. .SH SYNOPSIS @@ -27,12 +27,7 @@ each match attempt. Modifiers on external or internal command lines, the patterns, and the subject lines specify PCRE2 function options, control how the subject is processed, and what output is produced. .P -As the original fairly simple PCRE library evolved, it acquired many different -features, and as a result, the original \fBpcretest\fP program ended up with a -lot of options in a messy, arcane syntax for testing all the features. The -move to the new PCRE2 API provided an opportunity to re-implement the test -program as \fBpcre2test\fP, with a cleaner modifier syntax. Nevertheless, there -are still many obscure modifiers, some of which are specifically designed for +There are many obscure modifiers, some of which are specifically designed for use in conjunction with the test script and data files that are distributed as part of PCRE2. All the modifiers are documented here, some without much justification, but many of them are unlikely to be of use except when testing @@ -61,10 +56,10 @@ names used in the libraries have a suffix _8, _16, or _32, as appropriate. .rs .sp Input to \fBpcre2test\fP is processed line by line, either by calling the C -library's \fBfgets()\fP function, or via the \fBlibreadline\fP library. In some -Windows environments character 26 (hex 1A) causes an immediate end of file, and -no further data is read, so this character should be avoided unless you really -want that action. +library's \fBfgets()\fP function, or via the \fBlibreadline\fP or \fBlibedit\fP +library. In some Windows environments character 26 (hex 1A) causes an immediate +end of file, and no further data is read, so this character should be avoided +unless you really want that action. .P The input is processed using using C's string functions, so must not contain binary zeros, even though in Unix-like environments, \fBfgets()\fP @@ -273,7 +268,7 @@ test data, command lines that begin with # may appear. This file format, with some restrictions, can also be processed by the \fBperltest.sh\fP script that is distributed with PCRE2 as a means of checking that the behaviour of PCRE2 and Perl is the same. For a specification of \fBperltest.sh\fP, see the -comments near its beginning. +comments near its beginning. See also the #perltest command below. .P When the input is a terminal, \fBpcre2test\fP prompts for each line of input, using "re>" to prompt for regular expression patterns, and "data>" to prompt @@ -369,14 +364,19 @@ patterns. Modifiers on a pattern can change these settings. .sp #perltest .sp -The appearance of this line causes all subsequent modifier settings to be -checked for compatibility with the \fBperltest.sh\fP script, which is used to -confirm that Perl gives the same results as PCRE2. Also, apart from comment -lines, #pattern commands, and #subject commands that set or unset "mark", no -command lines are permitted, because they and many of the modifiers are -specific to \fBpcre2test\fP, and should not be used in test files that are also -processed by \fBperltest.sh\fP. The \fB#perltest\fP command helps detect tests -that are accidentally put in the wrong file. +This line is used in test files that can also be processed by \fBperltest.sh\fP +to confirm that Perl gives the same results as PCRE2. Subsequent tests are +checked for the use of \fBpcre2test\fP features that are incompatible with the +\fBperltest.sh\fP script. +.P +Patterns must use '/' as their delimiter, and only certain modifiers are +supported. Comment lines, #pattern commands, and #subject commands that set or +unset "mark" are recognized and acted on. The #perltest, #forbid_utf, and +#newline_default commands, which are needed in the relevant pcre2test files, +are silently ignored. All other command lines are ignored, but give a warning +message. The \fB#perltest\fP command helps detect tests that are accidentally +put in the wrong file or use the wrong delimiter. For more details of the +\fBperltest.sh\fP script see the comments it contains. .sp #pop [ ] #popcopy [ ] @@ -438,15 +438,17 @@ excluding pattern meta-characters): .sp This is interpreted as the pattern's delimiter. A regular expression may be continued over several input lines, in which case the newline characters are -included within it. It is possible to include the delimiter within the pattern -by escaping it with a backslash, for example +included within it. It is possible to include the delimiter as a literal within +the pattern by escaping it with a backslash, for example .sp /abc\e/def/ .sp If you do this, the escape and the delimiter form part of the pattern, but -since the delimiters are all non-alphanumeric, this does not affect its -interpretation. If the terminating delimiter is immediately followed by a -backslash, for example, +since the delimiters are all non-alphanumeric, the inclusion of the backslash +does not affect the pattern's interpretation. Note, however, that this trick +does not work within \eQ...\eE literal bracketing because the backslash will +itself be interpreted as a literal. If the terminating delimiter is immediately +followed by a backslash, for example, .sp /abc/\e .sp @@ -465,11 +467,11 @@ A pattern can be followed by a modifier list (details below). .SH "SUBJECT LINE SYNTAX" .rs .sp -Before each subject line is passed to \fBpcre2_match()\fP or -\fBpcre2_dfa_match()\fP, leading and trailing white space is removed, and the -line is scanned for backslash escapes, unless the \fBsubject_literal\fP -modifier was set for the pattern. The following provide a means of encoding -non-printing characters in a visible way: +Before each subject line is passed to \fBpcre2_match()\fP, +\fBpcre2_dfa_match()\fP, or \fBpcre2_jit_match()\fP, leading and trailing white +space is removed, and the line is scanned for backslash escapes, unless the +\fBsubject_literal\fP modifier was set for the pattern. The following provide a +means of encoding non-printing characters in a visible way: .sp \ea alarm (BEL, \ex07) \eb backspace (\ex08) @@ -565,6 +567,7 @@ way \fBpcre2_compile()\fP behaves. See for a description of the effects of these options. .sp allow_empty_class set PCRE2_ALLOW_EMPTY_CLASS + allow_lookaround_bsk set PCRE2_EXTRA_ALLOW_LOOKAROUND_BSK allow_surrogate_escapes set PCRE2_EXTRA_ALLOW_SURROGATE_ESCAPES alt_bsux set PCRE2_ALT_BSUX alt_circumflex set PCRE2_ALT_CIRCUMFLEX @@ -1175,7 +1178,7 @@ its input), you must use \fBposix_startend\fP to specify its length. The following modifiers affect the matching process or request additional information. Some of them may also be specified on a pattern line (see above), in which case they apply to every subject line that is matched against that -pattern. +pattern, but can be overridden by modifiers on the subject. .sp aftertext show text after match allaftertext show text after captures @@ -1384,6 +1387,10 @@ called instead of one of the matching functions (or after one call of replacement strings cannot contain commas, because a comma signifies the end of a modifier. This is not thought to be an issue in a test program. .P +Specifying a completely empty replacement string disables this modifier. +However, it is possible to specify an empty replacement by providing a buffer +length, as described below, for an otherwise empty replacement. +.P Unlike subject strings, \fBpcre2test\fP does not process replacement strings for escape sequences. In UTF mode, a replacement string is checked to see if it is a valid UTF-8 string. If so, it is correctly converted to a UTF string of @@ -2087,7 +2094,7 @@ on the stack. .sp .nf Philip Hazel -University Computing Service +Retired from University Computing Service Cambridge, England. .fi . @@ -2096,6 +2103,6 @@ Cambridge, England. .rs .sp .nf -Last updated: 20 March 2020 -Copyright (c) 1997-2020 University of Cambridge. +Last updated: 30 August 2021 +Copyright (c) 1997-2021 University of Cambridge. .fi diff --git a/pcre2/doc/pcre2test.txt b/pcre2/doc/pcre2test.txt index c0ba83f..217bed5 100644 --- a/pcre2/doc/pcre2test.txt +++ b/pcre2/doc/pcre2test.txt @@ -24,17 +24,11 @@ SYNOPSIS tion options, control how the subject is processed, and what output is produced. - As the original fairly simple PCRE library evolved, it acquired many - different features, and as a result, the original pcretest program - ended up with a lot of options in a messy, arcane syntax for testing - all the features. The move to the new PCRE2 API provided an opportunity - to re-implement the test program as pcre2test, with a cleaner modifier - syntax. Nevertheless, there are still many obscure modifiers, some of - which are specifically designed for use in conjunction with the test - script and data files that are distributed as part of PCRE2. All the - modifiers are documented here, some without much justification, but - many of them are unlikely to be of use except when testing the li- - braries. + There are many obscure modifiers, some of which are specifically de- + signed for use in conjunction with the test script and data files that + are distributed as part of PCRE2. All the modifiers are documented + here, some without much justification, but many of them are unlikely to + be of use except when testing the libraries. PCRE2's 8-BIT, 16-BIT AND 32-BIT LIBRARIES @@ -58,10 +52,10 @@ PCRE2's 8-BIT, 16-BIT AND 32-BIT LIBRARIES INPUT ENCODING Input to pcre2test is processed line by line, either by calling the C - library's fgets() function, or via the libreadline library. In some - Windows environments character 26 (hex 1A) causes an immediate end of - file, and no further data is read, so this character should be avoided - unless you really want that action. + library's fgets() function, or via the libreadline or libedit library. + In some Windows environments character 26 (hex 1A) causes an immediate + end of file, and no further data is read, so this character should be + avoided unless you really want that action. The input is processed using using C's string functions, so must not contain binary zeros, even though in Unix-like environments, fgets() @@ -257,127 +251,134 @@ DESCRIPTION appear. This file format, with some restrictions, can also be processed by the perltest.sh script that is distributed with PCRE2 as a means of checking that the behaviour of PCRE2 and Perl is the same. For a speci- - fication of perltest.sh, see the comments near its beginning. + fication of perltest.sh, see the comments near its beginning. See also + the #perltest command below. When the input is a terminal, pcre2test prompts for each line of input, - using "re>" to prompt for regular expression patterns, and "data>" to - prompt for subject lines. Command lines starting with # can be entered + using "re>" to prompt for regular expression patterns, and "data>" to + prompt for subject lines. Command lines starting with # can be entered only in response to the "re>" prompt. - Each subject line is matched separately and independently. If you want + Each subject line is matched separately and independently. If you want to do multi-line matches, you have to use the \n escape sequence (or \r - or \r\n, etc., depending on the newline setting) in a single line of - input to encode the newline sequences. There is no limit on the length - of subject lines; the input buffer is automatically extended if it is - too small. There are replication features that makes it possible to - generate long repetitive pattern or subject lines without having to + or \r\n, etc., depending on the newline setting) in a single line of + input to encode the newline sequences. There is no limit on the length + of subject lines; the input buffer is automatically extended if it is + too small. There are replication features that makes it possible to + generate long repetitive pattern or subject lines without having to supply them explicitly. - An empty line or the end of the file signals the end of the subject - lines for a test, at which point a new pattern or command line is ex- + An empty line or the end of the file signals the end of the subject + lines for a test, at which point a new pattern or command line is ex- pected if there is still input to be read. COMMAND LINES - In between sets of test data, a line that begins with # is interpreted + In between sets of test data, a line that begins with # is interpreted as a command line. If the first character is followed by white space or - an exclamation mark, the line is treated as a comment, and ignored. + an exclamation mark, the line is treated as a comment, and ignored. Otherwise, the following commands are recognized: #forbid_utf - Subsequent patterns automatically have the PCRE2_NEVER_UTF and - PCRE2_NEVER_UCP options set, which locks out the use of the PCRE2_UTF - and PCRE2_UCP options and the use of (*UTF) and (*UCP) at the start of - patterns. This command also forces an error if a subsequent pattern - contains any occurrences of \P, \p, or \X, which are still supported - when PCRE2_UTF is not set, but which require Unicode property support + Subsequent patterns automatically have the PCRE2_NEVER_UTF and + PCRE2_NEVER_UCP options set, which locks out the use of the PCRE2_UTF + and PCRE2_UCP options and the use of (*UTF) and (*UCP) at the start of + patterns. This command also forces an error if a subsequent pattern + contains any occurrences of \P, \p, or \X, which are still supported + when PCRE2_UTF is not set, but which require Unicode property support to be included in the library. - This is a trigger guard that is used in test files to ensure that UTF - or Unicode property tests are not accidentally added to files that are - used when Unicode support is not included in the library. Setting - PCRE2_NEVER_UTF and PCRE2_NEVER_UCP as a default can also be obtained - by the use of #pattern; the difference is that #forbid_utf cannot be - unset, and the automatic options are not displayed in pattern informa- + This is a trigger guard that is used in test files to ensure that UTF + or Unicode property tests are not accidentally added to files that are + used when Unicode support is not included in the library. Setting + PCRE2_NEVER_UTF and PCRE2_NEVER_UCP as a default can also be obtained + by the use of #pattern; the difference is that #forbid_utf cannot be + unset, and the automatic options are not displayed in pattern informa- tion, to avoid cluttering up test output. #load This command is used to load a set of precompiled patterns from a file, - as described in the section entitled "Saving and restoring compiled + as described in the section entitled "Saving and restoring compiled patterns" below. #loadtables - This command is used to load a set of binary character tables that can - be accessed by the tables=3 qualifier. Such tables can be created by + This command is used to load a set of binary character tables that can + be accessed by the tables=3 qualifier. Such tables can be created by the pcre2_dftables program with the -b option. #newline_default [ ] - When PCRE2 is built, a default newline convention can be specified. - This determines which characters and/or character pairs are recognized + When PCRE2 is built, a default newline convention can be specified. + This determines which characters and/or character pairs are recognized as indicating a newline in a pattern or subject string. The default can - be overridden when a pattern is compiled. The standard test files con- - tain tests of various newline conventions, but the majority of the - tests expect a single linefeed to be recognized as a newline by de- - fault. Without special action the tests would fail when PCRE2 is com- + be overridden when a pattern is compiled. The standard test files con- + tain tests of various newline conventions, but the majority of the + tests expect a single linefeed to be recognized as a newline by de- + fault. Without special action the tests would fail when PCRE2 is com- piled with either CR or CRLF as the default newline. The #newline_default command specifies a list of newline types that are - acceptable as the default. The types must be one of CR, LF, CRLF, ANY- + acceptable as the default. The types must be one of CR, LF, CRLF, ANY- CRLF, ANY, or NUL (in upper or lower case), for example: #newline_default LF Any anyCRLF If the default newline is in the list, this command has no effect. Oth- - erwise, except when testing the POSIX API, a newline modifier that + erwise, except when testing the POSIX API, a newline modifier that specifies the first newline convention in the list (LF in the above ex- - ample) is added to any pattern that does not already have a newline + ample) is added to any pattern that does not already have a newline modifier. If the newline list is empty, the feature is turned off. This command is present in a number of the standard test input files. - When the POSIX API is being tested there is no way to override the de- + When the POSIX API is being tested there is no way to override the de- fault newline convention, though it is possible to set the newline con- - vention from within the pattern. A warning is given if the posix or - posix_nosub modifier is used when #newline_default would set a default + vention from within the pattern. A warning is given if the posix or + posix_nosub modifier is used when #newline_default would set a default for the non-POSIX API. #pattern - This command sets a default modifier list that applies to all subse- + This command sets a default modifier list that applies to all subse- quent patterns. Modifiers on a pattern can change these settings. #perltest - The appearance of this line causes all subsequent modifier settings to - be checked for compatibility with the perltest.sh script, which is used - to confirm that Perl gives the same results as PCRE2. Also, apart from - comment lines, #pattern commands, and #subject commands that set or un- - set "mark", no command lines are permitted, because they and many of - the modifiers are specific to pcre2test, and should not be used in test - files that are also processed by perltest.sh. The #perltest command - helps detect tests that are accidentally put in the wrong file. + This line is used in test files that can also be processed by perl- + test.sh to confirm that Perl gives the same results as PCRE2. Subse- + quent tests are checked for the use of pcre2test features that are in- + compatible with the perltest.sh script. + + Patterns must use '/' as their delimiter, and only certain modifiers + are supported. Comment lines, #pattern commands, and #subject commands + that set or unset "mark" are recognized and acted on. The #perltest, + #forbid_utf, and #newline_default commands, which are needed in the + relevant pcre2test files, are silently ignored. All other command lines + are ignored, but give a warning message. The #perltest command helps + detect tests that are accidentally put in the wrong file or use the + wrong delimiter. For more details of the perltest.sh script see the + comments it contains. #pop [ ] #popcopy [ ] - These commands are used to manipulate the stack of compiled patterns, - as described in the section entitled "Saving and restoring compiled + These commands are used to manipulate the stack of compiled patterns, + as described in the section entitled "Saving and restoring compiled patterns" below. #save - This command is used to save a set of compiled patterns to a file, as - described in the section entitled "Saving and restoring compiled pat- + This command is used to save a set of compiled patterns to a file, as + described in the section entitled "Saving and restoring compiled pat- terns" below. #subject - This command sets a default modifier list that applies to all subse- - quent subject lines. Modifiers on a subject line can change these set- + This command sets a default modifier list that applies to all subse- + quent subject lines. Modifiers on a subject line can change these set- tings. @@ -385,47 +386,50 @@ MODIFIER SYNTAX Modifier lists are used with both pattern and subject lines. Items in a list are separated by commas followed by optional white space. Trailing - whitespace in a modifier list is ignored. Some modifiers may be given - for both patterns and subject lines, whereas others are valid only for - one or the other. Each modifier has a long name, for example "an- - chored", and some of them must be followed by an equals sign and a - value, for example, "offset=12". Values cannot contain comma charac- - ters, but may contain spaces. Modifiers that do not take values may be + whitespace in a modifier list is ignored. Some modifiers may be given + for both patterns and subject lines, whereas others are valid only for + one or the other. Each modifier has a long name, for example "an- + chored", and some of them must be followed by an equals sign and a + value, for example, "offset=12". Values cannot contain comma charac- + ters, but may contain spaces. Modifiers that do not take values may be preceded by a minus sign to turn off a previous setting. A few of the more common modifiers can also be specified as single let- - ters, for example "i" for "caseless". In documentation, following the + ters, for example "i" for "caseless". In documentation, following the Perl convention, these are written with a slash ("the /i modifier") for - clarity. Abbreviated modifiers must all be concatenated in the first - item of a modifier list. If the first item is not recognized as a long - modifier name, it is interpreted as a sequence of these abbreviations. + clarity. Abbreviated modifiers must all be concatenated in the first + item of a modifier list. If the first item is not recognized as a long + modifier name, it is interpreted as a sequence of these abbreviations. For example: /abc/ig,newline=cr,jit=3 - This is a pattern line whose modifier list starts with two one-letter - modifiers (/i and /g). The lower-case abbreviated modifiers are the + This is a pattern line whose modifier list starts with two one-letter + modifiers (/i and /g). The lower-case abbreviated modifiers are the same as used in Perl. PATTERN SYNTAX - A pattern line must start with one of the following characters (common + A pattern line must start with one of the following characters (common symbols, excluding pattern meta-characters): / ! " ' ` - = _ : ; , % & @ ~ - This is interpreted as the pattern's delimiter. A regular expression - may be continued over several input lines, in which case the newline + This is interpreted as the pattern's delimiter. A regular expression + may be continued over several input lines, in which case the newline characters are included within it. It is possible to include the delim- - iter within the pattern by escaping it with a backslash, for example + iter as a literal within the pattern by escaping it with a backslash, + for example /abc\/def/ If you do this, the escape and the delimiter form part of the pattern, - but since the delimiters are all non-alphanumeric, this does not affect - its interpretation. If the terminating delimiter is immediately fol- - lowed by a backslash, for example, + but since the delimiters are all non-alphanumeric, the inclusion of the + backslash does not affect the pattern's interpretation. Note, however, + that this trick does not work within \Q...\E literal bracketing because + the backslash will itself be interpreted as a literal. If the terminat- + ing delimiter is immediately followed by a backslash, for example, /abc/\ @@ -444,11 +448,11 @@ PATTERN SYNTAX SUBJECT LINE SYNTAX - Before each subject line is passed to pcre2_match() or - pcre2_dfa_match(), leading and trailing white space is removed, and the - line is scanned for backslash escapes, unless the subject_literal modi- - fier was set for the pattern. The following provide a means of encoding - non-printing characters in a visible way: + Before each subject line is passed to pcre2_match(), pcre2_dfa_match(), + or pcre2_jit_match(), leading and trailing white space is removed, and + the line is scanned for backslash escapes, unless the subject_literal + modifier was set for the pattern. The following provide a means of en- + coding non-printing characters in a visible way: \a alarm (BEL, \x07) \b backspace (\x08) @@ -543,6 +547,7 @@ PATTERN MODIFIERS options. allow_empty_class set PCRE2_ALLOW_EMPTY_CLASS + allow_lookaround_bsk set PCRE2_EXTRA_ALLOW_LOOKAROUND_BSK allow_surrogate_escapes set PCRE2_EXTRA_ALLOW_SURROGATE_ESCAPES alt_bsux set PCRE2_ALT_BSUX alt_circumflex set PCRE2_ALT_CIRCUMFLEX @@ -1077,7 +1082,8 @@ SUBJECT MODIFIERS The following modifiers affect the matching process or request addi- tional information. Some of them may also be specified on a pattern line (see above), in which case they apply to every subject line that - is matched against that pattern. + is matched against that pattern, but can be overridden by modifiers on + the subject. aftertext show text after match allaftertext show text after captures @@ -1125,29 +1131,29 @@ SUBJECT MODIFIERS zero_terminate pass the subject as zero-terminated The effects of these modifiers are described in the following sections. - When matching via the POSIX wrapper API, the aftertext, allaftertext, - and ovector subject modifiers work as described below. All other modi- + When matching via the POSIX wrapper API, the aftertext, allaftertext, + and ovector subject modifiers work as described below. All other modi- fiers are either ignored, with a warning message, or cause an error. Showing more text - The aftertext modifier requests that as well as outputting the part of + The aftertext modifier requests that as well as outputting the part of the subject string that matched the entire pattern, pcre2test should in addition output the remainder of the subject string. This is useful for tests where the subject contains multiple copies of the same substring. - The allaftertext modifier requests the same action for captured sub- + The allaftertext modifier requests the same action for captured sub- strings as well as the main matched substring. In each case the remain- der is output on the following line with a plus character following the capture number. - The allusedtext modifier requests that all the text that was consulted - during a successful pattern match by the interpreter should be shown, - for both full and partial matches. This feature is not supported for - JIT matching, and if requested with JIT it is ignored (with a warning - message). Setting this modifier affects the output if there is a look- - behind at the start of a match, or, for a complete match, a lookahead + The allusedtext modifier requests that all the text that was consulted + during a successful pattern match by the interpreter should be shown, + for both full and partial matches. This feature is not supported for + JIT matching, and if requested with JIT it is ignored (with a warning + message). Setting this modifier affects the output if there is a look- + behind at the start of a match, or, for a complete match, a lookahead at the end, or if \K is used in the pattern. Characters that precede or - follow the start and end of the actual match are indicated in the out- + follow the start and end of the actual match are indicated in the out- put by '<' or '>' characters underneath them. Here is an example: re> /(?<=pqr)abc(?=xyz)/ @@ -1158,16 +1164,16 @@ SUBJECT MODIFIERS Partial match: pqrabcxy <<< - The first, complete match shows that the matched string is "abc", with - the preceding and following strings "pqr" and "xyz" having been con- - sulted during the match (when processing the assertions). The partial + The first, complete match shows that the matched string is "abc", with + the preceding and following strings "pqr" and "xyz" having been con- + sulted during the match (when processing the assertions). The partial match can indicate only the preceding string. - The startchar modifier requests that the starting character for the - match be indicated, if it is different to the start of the matched + The startchar modifier requests that the starting character for the + match be indicated, if it is different to the start of the matched string. The only time when this occurs is when \K has been processed as part of the match. In this situation, the output for the matched string - is displayed from the starting character instead of from the match + is displayed from the starting character instead of from the match point, with circumflex characters under the earlier characters. For ex- ample: @@ -1176,7 +1182,7 @@ SUBJECT MODIFIERS 0: abcxyz ^^^ - Unlike allusedtext, the startchar modifier can be used with JIT. How- + Unlike allusedtext, the startchar modifier can be used with JIT. How- ever, these two modifiers are mutually exclusive. Showing the value of all capture groups @@ -1184,91 +1190,96 @@ SUBJECT MODIFIERS The allcaptures modifier requests that the values of all potential cap- tured parentheses be output after a match. By default, only those up to the highest one actually used in the match are output (corresponding to - the return code from pcre2_match()). Groups that did not take part in - the match are output as " ". This modifier is not relevant for - DFA matching (which does no capturing) and does not apply when replace + the return code from pcre2_match()). Groups that did not take part in + the match are output as " ". This modifier is not relevant for + DFA matching (which does no capturing) and does not apply when replace is specified; it is ignored, with a warning message, if present. Showing the entire ovector, for all outcomes The allvector modifier requests that the entire ovector be shown, what- ever the outcome of the match. Compare allcaptures, which shows only up - to the maximum number of capture groups for the pattern, and then only - for a successful complete non-DFA match. This modifier, which acts af- - ter any match result, and also for DFA matching, provides a means of - checking that there are no unexpected modifications to ovector fields. - Before each match attempt, the ovector is filled with a special value, - and if this is found in both elements of a capturing pair, " " is output. After a successful match, this applies to all - groups after the maximum capture group for the pattern. In other cases - it applies to the entire ovector. After a partial match, the first two - elements are the only ones that should be set. After a DFA match, the - amount of ovector that is used depends on the number of matches that + to the maximum number of capture groups for the pattern, and then only + for a successful complete non-DFA match. This modifier, which acts af- + ter any match result, and also for DFA matching, provides a means of + checking that there are no unexpected modifications to ovector fields. + Before each match attempt, the ovector is filled with a special value, + and if this is found in both elements of a capturing pair, " " is output. After a successful match, this applies to all + groups after the maximum capture group for the pattern. In other cases + it applies to the entire ovector. After a partial match, the first two + elements are the only ones that should be set. After a DFA match, the + amount of ovector that is used depends on the number of matches that were found. Testing pattern callouts - A callout function is supplied when pcre2test calls the library match- - ing functions, unless callout_none is specified. Its behaviour can be - controlled by various modifiers listed above whose names begin with - callout_. Details are given in the section entitled "Callouts" below. - Testing callouts from pcre2_substitute() is decribed separately in + A callout function is supplied when pcre2test calls the library match- + ing functions, unless callout_none is specified. Its behaviour can be + controlled by various modifiers listed above whose names begin with + callout_. Details are given in the section entitled "Callouts" below. + Testing callouts from pcre2_substitute() is decribed separately in "Testing the substitution function" below. Finding all matches in a string Searching for all possible matches within a subject can be requested by - the global or altglobal modifier. After finding a match, the matching - function is called again to search the remainder of the subject. The - difference between global and altglobal is that the former uses the - start_offset argument to pcre2_match() or pcre2_dfa_match() to start - searching at a new point within the entire string (which is what Perl + the global or altglobal modifier. After finding a match, the matching + function is called again to search the remainder of the subject. The + difference between global and altglobal is that the former uses the + start_offset argument to pcre2_match() or pcre2_dfa_match() to start + searching at a new point within the entire string (which is what Perl does), whereas the latter passes over a shortened subject. This makes a difference to the matching process if the pattern begins with a lookbe- hind assertion (including \b or \B). - If an empty string is matched, the next match is done with the + If an empty string is matched, the next match is done with the PCRE2_NOTEMPTY_ATSTART and PCRE2_ANCHORED flags set, in order to search for another, non-empty, match at the same point in the subject. If this - match fails, the start offset is advanced, and the normal match is re- - tried. This imitates the way Perl handles such cases when using the /g - modifier or the split() function. Normally, the start offset is ad- - vanced by one character, but if the newline convention recognizes CRLF - as a newline, and the current character is CR followed by LF, an ad- + match fails, the start offset is advanced, and the normal match is re- + tried. This imitates the way Perl handles such cases when using the /g + modifier or the split() function. Normally, the start offset is ad- + vanced by one character, but if the newline convention recognizes CRLF + as a newline, and the current character is CR followed by LF, an ad- vance of two characters occurs. Testing substring extraction functions - The copy and get modifiers can be used to test the pcre2_sub- + The copy and get modifiers can be used to test the pcre2_sub- string_copy_xxx() and pcre2_substring_get_xxx() functions. They can be given more than once, and each can specify a capture group name or num- ber, for example: abcd\=copy=1,copy=3,get=G1 - If the #subject command is used to set default copy and/or get lists, - these can be unset by specifying a negative number to cancel all num- + If the #subject command is used to set default copy and/or get lists, + these can be unset by specifying a negative number to cancel all num- bered groups and an empty name to cancel all named groups. - The getall modifier tests pcre2_substring_list_get(), which extracts + The getall modifier tests pcre2_substring_list_get(), which extracts all captured substrings. - If the subject line is successfully matched, the substrings extracted - by the convenience functions are output with C, G, or L after the - string number instead of a colon. This is in addition to the normal - full list. The string length (that is, the return from the extraction + If the subject line is successfully matched, the substrings extracted + by the convenience functions are output with C, G, or L after the + string number instead of a colon. This is in addition to the normal + full list. The string length (that is, the return from the extraction function) is given in parentheses after each substring, followed by the name when the extraction was by name. Testing the substitution function - If the replace modifier is set, the pcre2_substitute() function is - called instead of one of the matching functions (or after one call of - pcre2_match() in the case of PCRE2_SUBSTITUTE_MATCHED). Note that re- - placement strings cannot contain commas, because a comma signifies the - end of a modifier. This is not thought to be an issue in a test pro- + If the replace modifier is set, the pcre2_substitute() function is + called instead of one of the matching functions (or after one call of + pcre2_match() in the case of PCRE2_SUBSTITUTE_MATCHED). Note that re- + placement strings cannot contain commas, because a comma signifies the + end of a modifier. This is not thought to be an issue in a test pro- gram. + Specifying a completely empty replacement string disables this modi- + fier. However, it is possible to specify an empty replacement by pro- + viding a buffer length, as described below, for an otherwise empty re- + placement. + Unlike subject strings, pcre2test does not process replacement strings for escape sequences. In UTF mode, a replacement string is checked to see if it is a valid UTF-8 string. If so, it is correctly converted to @@ -1916,11 +1927,11 @@ SEE ALSO AUTHOR Philip Hazel - University Computing Service + Retired from University Computing Service Cambridge, England. REVISION - Last updated: 20 March 2020 - Copyright (c) 1997-2020 University of Cambridge. + Last updated: 30 August 2021 + Copyright (c) 1997-2021 University of Cambridge. diff --git a/pcre2/index.md b/pcre2/index.md new file mode 100644 index 0000000..7295ded --- /dev/null +++ b/pcre2/index.md @@ -0,0 +1,56 @@ +# PCRE2 - Perl-Compatible Regular Expressions + +The PCRE2 library is a set of C functions that implement regular expression +pattern matching using the same syntax and semantics as Perl 5. PCRE2 has its +own native API, as well as a set of wrapper functions that correspond to the +POSIX regular expression API. The PCRE2 library is free, even for building +proprietary software. It comes in three forms, for processing 8-bit, 16-bit, +or 32-bit code units, in either literal or UTF encoding. + +PCRE2 was first released in 2015 to replace the API in the original PCRE +library, which is now obsolete and no longer maintained. As well as a more +flexible API, the code of PCRE2 has been much improved since the fork. + +## Download + +As well as downloading from the +[GitHub site](https://github.com/PhilipHazel/pcre2), you can download PCRE2 +or the older, unmaintained PCRE1 library from an +[*unofficial* mirror](https://sourceforge.net/projects/pcre/files/) at SourceForge. + +You can check out the PCRE2 source code via Git or Subversion: + + git clone https://github.com/PhilipHazel/pcre2.git + svn co https://github.com/PhilipHazel/pcre2.git + +## Contributed Ports + +If you just need the command-line PCRE2 tools on Windows, precompiled binary +versions are available at this +[Rexegg page](http://www.rexegg.com/pcregrep-pcretest.html). + +A PCRE2 port for z/OS, a mainframe operating system which uses EBCDIC as its +default character encoding, can be found at +[http://www.cbttape.org](http://www.cbttape.org/) (File 939). + +## Documentation + +You can read the PCRE2 documentation +[here](https://philiphazel.github.io/pcre2/doc/html/index.html). + +Comparisons to Perl's regular expression semantics can be found in the +community authored Wikipedia entry for PCRE. + +There is a curated summary of changes for each PCRE release, copies of +documentation from older releases, and other useful information from the third +party authored +[RexEgg PCRE Documentation and Change Log page](http://www.rexegg.com/pcre-documentation.html). + +## Contact + +To report a problem with the PCRE2 library, or to make a feature request, please +use the PCRE2 GitHub issues tracker. There is a mailing list for discussion of + PCRE2 issues and development at pcre2-dev@googlegroups.com, which is where any +announcements will be made. You can browse the +[list archives](https://groups.google.com/g/pcre2-dev). + diff --git a/pcre2/libpcre2-16.pc.in b/pcre2/libpcre2-16.pc.in index 978040d..bacb466 100644 --- a/pcre2/libpcre2-16.pc.in +++ b/pcre2/libpcre2-16.pc.in @@ -8,6 +8,6 @@ includedir=@includedir@ Name: libpcre2-16 Description: PCRE2 - Perl compatible regular expressions C library (2nd API) with 16 bit character support Version: @PACKAGE_VERSION@ -Libs: -L${libdir} -lpcre2-16 +Libs: -L${libdir} -lpcre2-16@LIB_POSTFIX@ Libs.private: @PTHREAD_CFLAGS@ @PTHREAD_LIBS@ Cflags: -I${includedir} @PCRE2_STATIC_CFLAG@ diff --git a/pcre2/libpcre2-32.pc.in b/pcre2/libpcre2-32.pc.in index d8fb187..06241f0 100644 --- a/pcre2/libpcre2-32.pc.in +++ b/pcre2/libpcre2-32.pc.in @@ -8,6 +8,6 @@ includedir=@includedir@ Name: libpcre2-32 Description: PCRE2 - Perl compatible regular expressions C library (2nd API) with 32 bit character support Version: @PACKAGE_VERSION@ -Libs: -L${libdir} -lpcre2-32 +Libs: -L${libdir} -lpcre2-32@LIB_POSTFIX@ Libs.private: @PTHREAD_CFLAGS@ @PTHREAD_LIBS@ Cflags: -I${includedir} @PCRE2_STATIC_CFLAG@ diff --git a/pcre2/libpcre2-8.pc.in b/pcre2/libpcre2-8.pc.in index 5c872d0..246bb9e 100644 --- a/pcre2/libpcre2-8.pc.in +++ b/pcre2/libpcre2-8.pc.in @@ -8,6 +8,6 @@ includedir=@includedir@ Name: libpcre2-8 Description: PCRE2 - Perl compatible regular expressions C library (2nd API) with 8 bit character support Version: @PACKAGE_VERSION@ -Libs: -L${libdir} -lpcre2-8 +Libs: -L${libdir} -lpcre2-8@LIB_POSTFIX@ Libs.private: @PTHREAD_CFLAGS@ @PTHREAD_LIBS@ Cflags: -I${includedir} @PCRE2_STATIC_CFLAG@ diff --git a/pcre2/libpcre2-posix.pc.in b/pcre2/libpcre2-posix.pc.in index 9641555..758c306 100644 --- a/pcre2/libpcre2-posix.pc.in +++ b/pcre2/libpcre2-posix.pc.in @@ -8,6 +8,6 @@ includedir=@includedir@ Name: libpcre2-posix Description: Posix compatible interface to libpcre2-8 Version: @PACKAGE_VERSION@ -Libs: -L${libdir} -lpcre2-posix +Libs: -L${libdir} -lpcre2-posix@LIB_POSTFIX@ Cflags: -I${includedir} @PCRE2_STATIC_CFLAG@ Requires.private: libpcre2-8 diff --git a/pcre2/maint/GenerateUtt.py b/pcre2/maint/GenerateUtt.py index 7301938..eea6efc 100755 --- a/pcre2/maint/GenerateUtt.py +++ b/pcre2/maint/GenerateUtt.py @@ -28,6 +28,7 @@ # Added 'Unknown' script, 01-October-2018. # Added script names for Unicode 12.1.0, 27-July-2019. # Added script names for Unicode 13.0.0, 10-March-2020. +# Added Script names for Unicode 14.0.0, PCRE2-10.39 script_names = ['Unknown', 'Arabic', 'Armenian', 'Bengali', 'Bopomofo', 'Braille', 'Buginese', 'Buhid', 'Canadian_Aboriginal', \ 'Cherokee', 'Common', 'Coptic', 'Cypriot', 'Cyrillic', 'Deseret', 'Devanagari', 'Ethiopic', 'Georgian', \ @@ -66,7 +67,9 @@ script_names = ['Unknown', 'Arabic', 'Armenian', 'Bengali', 'Bopomofo', 'Braille # New for Unicode 12.0.0 'Elymaic', 'Nandinagari', 'Nyiakeng_Puachue_Hmong', 'Wancho', # New for Unicode 13.0.0 - 'Chorasmian', 'Dives_Akuru', 'Khitan_Small_Script', 'Yezidi' + 'Chorasmian', 'Dives_Akuru', 'Khitan_Small_Script', 'Yezidi', +# New for Unicode 14.0.0 + 'Cypro_Minoan', 'Old_Uyghur', 'Tangsa', 'Toto', 'Vithkuqi' ] category_names = ['Cc', 'Cf', 'Cn', 'Co', 'Cs', 'Ll', 'Lm', 'Lo', 'Lt', 'Lu', diff --git a/pcre2/maint/MultiStage2.py b/pcre2/maint/MultiStage2.py index cf7f657..10fa412 100755 --- a/pcre2/maint/MultiStage2.py +++ b/pcre2/maint/MultiStage2.py @@ -92,6 +92,7 @@ # 03-October-2018: Added new field for Script Extensions # 27-July-2019: Updated for Unicode 12.1.0 # 10-March-2020: Updated for Unicode 13.0.0 +# PCRE2-10.39: Updated for Unicode 14.0.0 # ---------------------------------------------------------------------------- # # @@ -432,7 +433,9 @@ script_names = ['Unknown', 'Arabic', 'Armenian', 'Bengali', 'Bopomofo', 'Braille # New for Unicode 12.0.0 'Elymaic', 'Nandinagari', 'Nyiakeng_Puachue_Hmong', 'Wancho', # New for Unicode 13.0.0 - 'Chorasmian', 'Dives_Akuru', 'Khitan_Small_Script', 'Yezidi' + 'Chorasmian', 'Dives_Akuru', 'Khitan_Small_Script', 'Yezidi', +# New for Unicode 14.0.0 + 'Cypro_Minoan', 'Old_Uyghur', 'Tangsa', 'Toto', 'Vithkuqi' ] script_abbrevs = [ @@ -469,8 +472,10 @@ script_abbrevs = [ #New for Unicode 12.0.0 'Elym', 'Nand', 'Hmnp', 'Wcho', #New for Unicode 13.0.0 - 'Chrs', 'Diak', 'Kits', 'Yezi' - ] + 'Chrs', 'Diak', 'Kits', 'Yezi', +#New for Unicode 14.0.0 + 'Cpmn', 'Ougr', 'Tngs', 'Toto', 'Vith' + ] category_names = ['Cc', 'Cf', 'Cn', 'Co', 'Cs', 'Ll', 'Lm', 'Lo', 'Lt', 'Lu', 'Mc', 'Me', 'Mn', 'Nd', 'Nl', 'No', 'Pc', 'Pd', 'Pe', 'Pf', 'Pi', 'Po', 'Ps', diff --git a/pcre2/maint/README b/pcre2/maint/README index fac36b2..ab9845c 100644 --- a/pcre2/maint/README +++ b/pcre2/maint/README @@ -54,8 +54,8 @@ Unicode.tables The files in this directory were downloaded from the Unicode ucptest.c A short C program for testing the Unicode property macros that do lookups in the pcre2_ucd.c data, mainly useful after rebuilding the Unicode property table. Compile and run this in - the "maint" directory (see comments at its head). This program - can also be used to find characters with specific properties. + the "maint" directory (see comments at its head). This program + can also be used to find characters with specific properties. ucptestdata A directory containing four files, testinput{1,2} and testoutput{1,2}, for use in conjunction with the ucptest @@ -129,7 +129,8 @@ distribution for a new release. different configurations, and it also runs some of them with valgrind, all of which can take quite some time. -. Run tests in both 32-bit and 64-bit environments if possible. +. Run tests in both 32-bit and 64-bit environments if possible. I can no longer + run 32-bit tests. . Run tests with two or more different compilers (e.g. clang and gcc), and make use of -fsanitize=address and friends where possible. For gcc, @@ -140,7 +141,8 @@ distribution for a new release. be added when compiling with JIT. Another useful clang option is -fsanitize=signed-integer-overflow -. Do a test build using CMake. +. Do a test build using CMake. Remove src/config.h first, lest it override the + version that CMake creates. Do NOT use parallel make. . Run perltest.sh on the test data for tests 1 and 4. The output should match the PCRE2 test output, apart from the version identification at the start of @@ -160,8 +162,7 @@ distribution for a new release. compiler as a change from gcc. Adding -xarch=v9 to the cc options does a 64-bit test, but it also needs -S 64 for pcre2test to increase the stack size for test 2. Since I retired I can no longer do much of this, but instead I - rely on putting out release candidates for folks on the pcre-dev list to - test. + rely on putting out release candidates for testing by the community. . The buildbots at http://buildfarm.opencsw.org/ do some automated testing of PCRE2 and should be checked before putting out a release. @@ -214,20 +215,19 @@ changes in a shared library: Making a PCRE2 release ====================== -Run PrepareRelease and commit the files that it changes (by removing trailing -spaces). The first thing this script does is to run CheckMan on the man pages; -if it finds any markup errors, it reports them and then aborts. +Run PrepareRelease and commit the files that it changes. The first thing this +script does is to run CheckMan on the man pages; if it finds any markup errors, +it reports them and then aborts. Otherwise it removes trailing spaces from +sources and refreshes the HTML documentation. Update the GitHub repository with +"git push". -Once PrepareRelease has run clean, run "make distcheck" to create the tarballs -and the zipball. Double-check with "svn status", then create an SVN tagged -copy: - - svn copy svn://vcs.exim.org/pcre2/code/trunk \ - svn://vcs.exim.org/pcre2/code/tags/pcre2-10.xx +Once PrepareRelease has run clean, run "make distcheck" to create the tarball +and the zipball. I then sign these files. Double-check with "git status" that +the repository is fully up-to-date, then create a new tag on GitHub. Upload the +tarball, zipball, and the signatures as "assets" of the GitHub release. When the new release is out, don't forget to tell webmaster@pcre.org and the -mailing list. Also, update the list of version numbers in Bugzilla -(administration > products > PCRE > Edit versions). +mailing list. Future ideas (wish list) @@ -235,7 +235,8 @@ Future ideas (wish list) This section records a list of ideas so that they do not get forgotten. They vary enormously in their usefulness and potential for implementation. Some are -very sensible; some are rather wacky. Some have been on this list for years. +very sensible; some are rather wacky. Some have been on this list for many +years. . Optimization @@ -276,9 +277,6 @@ very sensible; some are rather wacky. Some have been on this list for years. . An option to convert results into character offsets and character lengths. -. An option for pcre2grep to scan only the start of a file. I am not keen - - this is the job of "head". - . A (non-Unix) user wanted pcregrep options to (a) list a file name just once, preceded by a blank line, instead of adding it to every matched line, and (b) support --outputfile=name. @@ -317,10 +315,9 @@ very sensible; some are rather wacky. Some have been on this list for years. . PCRE2 cannot at present distinguish between subpatterns with different names, but the same number (created by the use of ?|). In order to do so, a way of - remembering *which* subpattern numbered n matched is needed. Bugzilla #760. - (*MARK) can perhaps be used as a way round this problem. However, note that - Perl does not distinguish: like PCRE2, a name is just an alias for a number - in Perl. + remembering *which* subpattern numbered n matched is needed. (*MARK) can + perhaps be used as a way round this problem. However, note that Perl does not + distinguish: like PCRE2, a name is just an alias for a number in Perl. . Instead of having #ifdef HAVE_CONFIG_H in each module, put #include "something" and the the #ifdef appears only in one place, in "something". @@ -348,8 +345,6 @@ very sensible; some are rather wacky. Some have been on this list for years. . (?[...]) extended classes: big project. -. Bugzilla #1694 requests backwards searching. - . Allow a callout to specify a number of characters to skip. This can be done compatibly via an extra callout field. @@ -361,9 +356,6 @@ very sensible; some are rather wacky. Some have been on this list for years. . A limit on substitutions: a user suggested somehow finding a way of making match_limit apply to the whole operation instead of each match separately. -. Redesign handling of class/nclass/xclass because the compile code logic is - currently very contorted and obscure. - . Some #defines could be replaced with enums to improve robustness. . There was a request for an option for pcre2_match() to return the longest @@ -380,7 +372,8 @@ very sensible; some are rather wacky. Some have been on this list for years. The test function could make use of get_substrings() to cover more code. . A neater way of handling recursion file names in pcre2grep, e.g. a single - buffer that can grow. + buffer that can grow. See also GitHub issue #2 (recursion looping via + symlinks). . A user suggested that before/after parameters in pcre2grep could have negative values, to list lines near to the matched line, but not necessarily @@ -395,14 +388,7 @@ very sensible; some are rather wacky. Some have been on this list for years. . Breaking loops that match an empty string: perhaps find a way of continuing if *something* has changed, but this might mean remembering additional data. "Something" could be a capture value, but then a list of previous values - would be needed to avoid a cycle of changes. Bugzilla #2182. - -. The use of \K in assertions is problematic. There was some talk of Perl - banning this, but it hasn't happened. Some problems could be avoided by - not allowing it to set a value before the match start; others by not allowing - it to set a value after the match end. This could be controlled by an option - such as PCRE2_SANE_BACKSLASH_K, for compatibility (or possibly make the sane - behaviour the default and implement PCRE2_INSANE_BACKSLASH_K). + would be needed to avoid a cycle of changes. . If a function could be written to find 3-character (or other length) fixed strings, at least one of which must be present for a match, efficient @@ -410,6 +396,8 @@ very sensible; some are rather wacky. Some have been on this list for years. . If pcre2grep had --first-line (match only in the first line) it could be efficiently used to find files "starting with xxx". What about --last-line? + There was also the suggestion of an option for pcre2grep to scan only the + start of a file. I am not keen - this is the job of "head". . A user requested a means of determining whether a failed match was failed by the start-of-match optimizations, or by running the match engine. Easy enough @@ -419,12 +407,14 @@ very sensible; some are rather wacky. Some have been on this list for years. interpreters? JIT already does some of this, but it may not be worth it for the interpreters. -. There was a request for a way of re-defining \w (and therefore \W, \b, and - \B). An in-pattern sequence such as (?w=[...]) was suggested. Easiest way - would be simply to inline the class, with lookarounds for \b and \B. Ideally - the setting should last till the end of the group, which means remembering - all previous settings; maybe a fixed amount of stack would do - how deep - would anyone want to nest these things? Bugzilla #2301. +. Redesign handling of class/nclass/xclass because the compile code logic is + currently very contorted and obscure. Also there was a request for a way of + re-defining \w (and therefore \W, \b, and \B). An in-pattern sequence such as + (?w=[...]) was suggested. Easiest way would be simply to inline the class, + with lookarounds for \b and \B. Ideally the setting should last till the end + of the group, which means remembering all previous settings; maybe a fixed + amount of stack would do - how deep would anyone want to nest these things? + See GitHub issue #13 for a compendium of character class issues. . Recognize the short script names. They are already listed in maint/ Multistage2.py because they are needed for scanning the script extensions @@ -437,7 +427,16 @@ very sensible; some are rather wacky. Some have been on this list for years. facility for a length limit in pcre2_config(), and what would be the encoding? +. Quantified groups with a fixed count currently operate by replicating the + group in the compiled bytecode. This may not really matter in these days of + gigabyte memory, but perhaps another implementation might be considered. + Needs coordination between the interpreters and JIT. + +. There are regular requests for variable-length lookbehinds. + +. See also any suggestions in the GitHub issues. + Philip Hazel -Email local part: ph10 -Email domain: cam.ac.uk -Last updated: 01 April 2020 +Email local part: Philip.Hazel +Email domain: gmail.com +Last updated: 26 August 2021 diff --git a/pcre2/maint/Unicode.tables/CaseFolding.txt b/pcre2/maint/Unicode.tables/CaseFolding.txt index 033788b..932ace2 100644 --- a/pcre2/maint/Unicode.tables/CaseFolding.txt +++ b/pcre2/maint/Unicode.tables/CaseFolding.txt @@ -1,6 +1,6 @@ -# CaseFolding-13.0.0.txt -# Date: 2019-09-08, 23:30:59 GMT -# © 2019 Unicode®, Inc. +# CaseFolding-14.0.0.txt +# Date: 2021-03-08, 19:35:41 GMT +# © 2021 Unicode®, Inc. # Unicode and the Unicode Logo are registered trademarks of Unicode, Inc. in the U.S. and other countries. # For terms of use, see http://www.unicode.org/terms_of_use.html # @@ -1050,6 +1050,7 @@ 2C2C; C; 2C5C; # GLAGOLITIC CAPITAL LETTER SHTAPIC 2C2D; C; 2C5D; # GLAGOLITIC CAPITAL LETTER TROKUTASTI A 2C2E; C; 2C5E; # GLAGOLITIC CAPITAL LETTER LATINATE MYSLITE +2C2F; C; 2C5F; # GLAGOLITIC CAPITAL LETTER CAUDATE CHRIVI 2C60; C; 2C61; # LATIN CAPITAL LETTER L WITH DOUBLE BAR 2C62; C; 026B; # LATIN CAPITAL LETTER L WITH MIDDLE TILDE 2C63; C; 1D7D; # LATIN CAPITAL LETTER P WITH STROKE @@ -1230,12 +1231,16 @@ A7B8; C; A7B9; # LATIN CAPITAL LETTER U WITH STROKE A7BA; C; A7BB; # LATIN CAPITAL LETTER GLOTTAL A A7BC; C; A7BD; # LATIN CAPITAL LETTER GLOTTAL I A7BE; C; A7BF; # LATIN CAPITAL LETTER GLOTTAL U +A7C0; C; A7C1; # LATIN CAPITAL LETTER OLD POLISH O A7C2; C; A7C3; # LATIN CAPITAL LETTER ANGLICANA W A7C4; C; A794; # LATIN CAPITAL LETTER C WITH PALATAL HOOK A7C5; C; 0282; # LATIN CAPITAL LETTER S WITH HOOK A7C6; C; 1D8E; # LATIN CAPITAL LETTER Z WITH PALATAL HOOK A7C7; C; A7C8; # LATIN CAPITAL LETTER D WITH SHORT STROKE OVERLAY A7C9; C; A7CA; # LATIN CAPITAL LETTER S WITH SHORT STROKE OVERLAY +A7D0; C; A7D1; # LATIN CAPITAL LETTER CLOSED INSULAR G +A7D6; C; A7D7; # LATIN CAPITAL LETTER MIDDLE SCOTS S +A7D8; C; A7D9; # LATIN CAPITAL LETTER SIGMOID S A7F5; C; A7F6; # LATIN CAPITAL LETTER REVERSED HALF H AB70; C; 13A0; # CHEROKEE SMALL LETTER A AB71; C; 13A1; # CHEROKEE SMALL LETTER E @@ -1431,6 +1436,41 @@ FF3A; C; FF5A; # FULLWIDTH LATIN CAPITAL LETTER Z 104D1; C; 104F9; # OSAGE CAPITAL LETTER GHA 104D2; C; 104FA; # OSAGE CAPITAL LETTER ZA 104D3; C; 104FB; # OSAGE CAPITAL LETTER ZHA +10570; C; 10597; # VITHKUQI CAPITAL LETTER A +10571; C; 10598; # VITHKUQI CAPITAL LETTER BBE +10572; C; 10599; # VITHKUQI CAPITAL LETTER BE +10573; C; 1059A; # VITHKUQI CAPITAL LETTER CE +10574; C; 1059B; # VITHKUQI CAPITAL LETTER CHE +10575; C; 1059C; # VITHKUQI CAPITAL LETTER DE +10576; C; 1059D; # VITHKUQI CAPITAL LETTER DHE +10577; C; 1059E; # VITHKUQI CAPITAL LETTER EI +10578; C; 1059F; # VITHKUQI CAPITAL LETTER E +10579; C; 105A0; # VITHKUQI CAPITAL LETTER FE +1057A; C; 105A1; # VITHKUQI CAPITAL LETTER GA +1057C; C; 105A3; # VITHKUQI CAPITAL LETTER HA +1057D; C; 105A4; # VITHKUQI CAPITAL LETTER HHA +1057E; C; 105A5; # VITHKUQI CAPITAL LETTER I +1057F; C; 105A6; # VITHKUQI CAPITAL LETTER IJE +10580; C; 105A7; # VITHKUQI CAPITAL LETTER JE +10581; C; 105A8; # VITHKUQI CAPITAL LETTER KA +10582; C; 105A9; # VITHKUQI CAPITAL LETTER LA +10583; C; 105AA; # VITHKUQI CAPITAL LETTER LLA +10584; C; 105AB; # VITHKUQI CAPITAL LETTER ME +10585; C; 105AC; # VITHKUQI CAPITAL LETTER NE +10586; C; 105AD; # VITHKUQI CAPITAL LETTER NJE +10587; C; 105AE; # VITHKUQI CAPITAL LETTER O +10588; C; 105AF; # VITHKUQI CAPITAL LETTER PE +10589; C; 105B0; # VITHKUQI CAPITAL LETTER QA +1058A; C; 105B1; # VITHKUQI CAPITAL LETTER RE +1058C; C; 105B3; # VITHKUQI CAPITAL LETTER SE +1058D; C; 105B4; # VITHKUQI CAPITAL LETTER SHE +1058E; C; 105B5; # VITHKUQI CAPITAL LETTER TE +1058F; C; 105B6; # VITHKUQI CAPITAL LETTER THE +10590; C; 105B7; # VITHKUQI CAPITAL LETTER U +10591; C; 105B8; # VITHKUQI CAPITAL LETTER VE +10592; C; 105B9; # VITHKUQI CAPITAL LETTER XE +10594; C; 105BB; # VITHKUQI CAPITAL LETTER Y +10595; C; 105BC; # VITHKUQI CAPITAL LETTER ZE 10C80; C; 10CC0; # OLD HUNGARIAN CAPITAL LETTER A 10C81; C; 10CC1; # OLD HUNGARIAN CAPITAL LETTER AA 10C82; C; 10CC2; # OLD HUNGARIAN CAPITAL LETTER EB diff --git a/pcre2/maint/Unicode.tables/DerivedGeneralCategory.txt b/pcre2/maint/Unicode.tables/DerivedGeneralCategory.txt index 3e82c7f..a36d42a 100644 --- a/pcre2/maint/Unicode.tables/DerivedGeneralCategory.txt +++ b/pcre2/maint/Unicode.tables/DerivedGeneralCategory.txt @@ -1,6 +1,6 @@ -# DerivedGeneralCategory-13.0.0.txt -# Date: 2019-10-21, 14:30:32 GMT -# © 2019 Unicode®, Inc. +# DerivedGeneralCategory-14.0.0.txt +# Date: 2021-07-10, 00:35:08 GMT +# © 2021 Unicode®, Inc. # Unicode and the Unicode Logo are registered trademarks of Unicode, Inc. in the U.S. and other countries. # For terms of use, see http://www.unicode.org/terms_of_use.html # @@ -27,7 +27,6 @@ 05C8..05CF ; Cn # [8] .. 05EB..05EE ; Cn # [4] .. 05F5..05FF ; Cn # [11] .. -061D ; Cn # 070E ; Cn # 074B..074C ; Cn # [2] .. 07B2..07BF ; Cn # [14] .. @@ -36,9 +35,9 @@ 083F ; Cn # 085C..085D ; Cn # [2] .. 085F ; Cn # -086B..089F ; Cn # [53] .. -08B5 ; Cn # -08C8..08D2 ; Cn # [11] .. +086B..086F ; Cn # [5] .. +088F ; Cn # +0892..0897 ; Cn # [6] .. 0984 ; Cn # 098D..098E ; Cn # [2] .. 0991..0992 ; Cn # [2] .. @@ -116,12 +115,13 @@ 0C0D ; Cn # 0C11 ; Cn # 0C29 ; Cn # -0C3A..0C3C ; Cn # [3] .. +0C3A..0C3B ; Cn # [2] .. 0C45 ; Cn # 0C49 ; Cn # 0C4E..0C54 ; Cn # [7] .. 0C57 ; Cn # -0C5B..0C5F ; Cn # [5] .. +0C5B..0C5C ; Cn # [2] .. +0C5E..0C5F ; Cn # [2] .. 0C64..0C65 ; Cn # [2] .. 0C70..0C76 ; Cn # [7] .. 0C8D ; Cn # @@ -132,7 +132,7 @@ 0CC5 ; Cn # 0CC9 ; Cn # 0CCE..0CD4 ; Cn # [7] .. -0CD7..0CDD ; Cn # [7] .. +0CD7..0CDC ; Cn # [6] .. 0CDF ; Cn # 0CE4..0CE5 ; Cn # [2] .. 0CF0 ; Cn # @@ -200,8 +200,7 @@ 13FE..13FF ; Cn # [2] .. 169D..169F ; Cn # [3] .. 16F9..16FF ; Cn # [7] .. -170D ; Cn # -1715..171F ; Cn # [11] .. +1716..171E ; Cn # [9] .. 1737..173F ; Cn # [9] .. 1754..175F ; Cn # [12] .. 176D ; Cn # @@ -210,7 +209,6 @@ 17DE..17DF ; Cn # [2] .. 17EA..17EF ; Cn # [6] .. 17FA..17FF ; Cn # [6] .. -180F ; Cn # 181A..181F ; Cn # [6] .. 1879..187F ; Cn # [7] .. 18AB..18AF ; Cn # [5] .. @@ -230,9 +228,9 @@ 1A8A..1A8F ; Cn # [6] .. 1A9A..1A9F ; Cn # [6] .. 1AAE..1AAF ; Cn # [2] .. -1AC1..1AFF ; Cn # [63] .. -1B4C..1B4F ; Cn # [4] .. -1B7D..1B7F ; Cn # [3] .. +1ACF..1AFF ; Cn # [49] .. +1B4D..1B4F ; Cn # [3] .. +1B7F ; Cn # 1BF4..1BFB ; Cn # [8] .. 1C38..1C3A ; Cn # [3] .. 1C4A..1C4C ; Cn # [3] .. @@ -240,7 +238,6 @@ 1CBB..1CBC ; Cn # [2] .. 1CC8..1CCF ; Cn # [8] .. 1CFB..1CFF ; Cn # [5] .. -1DFA ; Cn # 1F16..1F17 ; Cn # [2] .. 1F1E..1F1F ; Cn # [2] .. 1F46..1F47 ; Cn # [2] .. @@ -261,15 +258,13 @@ 2072..2073 ; Cn # [2] .. 208F ; Cn # 209D..209F ; Cn # [3] .. -20C0..20CF ; Cn # [16] .. +20C1..20CF ; Cn # [15] .. 20F1..20FF ; Cn # [15] .. 218C..218F ; Cn # [4] .. 2427..243F ; Cn # [25] .. 244B..245F ; Cn # [21] .. 2B74..2B75 ; Cn # [2] .. 2B96 ; Cn # -2C2F ; Cn # -2C5F ; Cn # 2CF4..2CF8 ; Cn # [5] .. 2D26 ; Cn # 2D28..2D2C ; Cn # [5] .. @@ -285,7 +280,7 @@ 2DCF ; Cn # 2DD7 ; Cn # 2DDF ; Cn # -2E53..2E7F ; Cn # [45] .. +2E5E..2E7F ; Cn # [34] .. 2E9A ; Cn #