From 5730aba947630c76fe084190f11f90aad88bd0de Mon Sep 17 00:00:00 2001
From: hinus <hinus@163.com>
Date: Fri, 13 Aug 2021 23:49:15 +0800
Subject: [PATCH 1/2] Title: System call 'utime'. Issue:
 https://gitee.com/hinus/linux_kernel_011/issues/I451NK Description: System
 call 'utime'

---
 fs/open.c        | 46 +++++++++++++++++++++++++++++++++++++++++-----
 include/unistd.h |  2 ++
 include/utime.h  | 13 +++++++++++++
 3 files changed, 56 insertions(+), 5 deletions(-)
 create mode 100644 include/utime.h

diff --git a/fs/open.c b/fs/open.c
index a9525c2..a7c982d 100644
--- a/fs/open.c
+++ b/fs/open.c
@@ -2,7 +2,7 @@
 #include <errno.h>
 #include <fcntl.h>
 #include <sys/types.h>
-
+#include <utime.h>
 #include <linux/sched.h>
 #include <linux/tty.h>
 #include <linux/kernel.h>
@@ -11,14 +11,50 @@
 
 #include <asm/segment.h>
 
-int sys_utime(char * filename) {
-    printk("unimplement sys call utime\n");
+int sys_utime(char * filename, struct utimbuf * times) {
+    struct m_inode * inode;
+    long actime,modtime;
+
+    if (!(inode=namei(filename)))
+        return -ENOENT;
+
+    if (times) {
+        actime = get_fs_long((unsigned long *) &times->actime);
+        modtime = get_fs_long((unsigned long *) &times->modtime);
+    }
+    else {
+        actime = modtime = CURRENT_TIME;
+    }
+
+    inode->i_atime = actime;
+    inode->i_mtime = modtime;
+    inode->i_dirt = 1;
+    iput(inode);
     return 0;
 }
 
 int sys_access(const char * filename,int mode) {
-    printk("unimplement sys call utime\n");
-    return 0;
+    struct m_inode * inode;
+    int res, i_mode;
+
+    mode &= 0007;
+    if (!(inode=namei(filename)))
+        return -EACCES;
+
+    i_mode = res = inode->i_mode & 0777;
+    iput(inode);
+    if (current->uid == inode->i_uid)
+        res >>= 6;
+    else if (current->gid == inode->i_gid)
+        res >>= 6;
+    if ((res & 0007 & mode) == mode)
+        return 0;
+
+    if ((!current->uid) &&
+            (!(mode & 1) || (i_mode & 0111)))
+        return 0;
+
+    return -EACCES;
 }
 
 int sys_ustat(int dev, struct ustat * ubuf) {
diff --git a/include/unistd.h b/include/unistd.h
index e114b7e..f94fe4c 100644
--- a/include/unistd.h
+++ b/include/unistd.h
@@ -9,6 +9,7 @@
 
 #include <sys/time.h>
 #include <sys/utsname.h>
+#include <utime.h>
 
 #ifdef __LIBRARY__
 
@@ -171,5 +172,6 @@ int rmdir(const char* pathname);
 time_t time(time_t * tloc);
 mode_t umask(mode_t mask);
 int uname(struct utsname * name);
+int utime(const char * filename, struct utimbuf * times);
 
 #endif
diff --git a/include/utime.h b/include/utime.h
new file mode 100644
index 0000000..43a6d2f
--- /dev/null
+++ b/include/utime.h
@@ -0,0 +1,13 @@
+#ifndef _UTIME_H
+#define _UTIME_H
+
+#include <sys/types.h>
+
+struct utimbuf {
+    time_t actime;
+    time_t modtime;
+};
+
+extern int utime(const char *filename, struct utimbuf *times);
+
+#endif
-- 
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From dd7d8ff24798d4206c2dc7c55fb66cf75fc3495c Mon Sep 17 00:00:00 2001
From: hinus <hinus@163.com>
Date: Sat, 14 Aug 2021 17:45:37 +0800
Subject: [PATCH 2/2] Title: use memset instead of struct copy. Issue:
 https://gitee.com/hinus/linux_kernel_011/issues/I45ITK Description: use
 memset instead of struct copy.

---
 kernel/fork.c   | 24 ++++++++----------------
 kernel/signal.c |  2 ++
 2 files changed, 10 insertions(+), 16 deletions(-)

diff --git a/kernel/fork.c b/kernel/fork.c
index 280319a..e203734 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -2,6 +2,7 @@
 
 #include <asm/system.h>
 #include <linux/sched.h>
+#include <string.h>
 
 long last_pid = 0;
 
@@ -62,20 +63,21 @@ int copy_process(int nr,long ebp,long edi,long esi,long gs,long none,
         return -EAGAIN;
 
     task[nr] = p;
-    *p = *current;
+    memcpy(p, current, sizeof(struct task_struct));
 
     p->pid = last_pid;
-    p->priority = current->priority;
     p->counter = p->priority;
+    p->signal = 0;
+    p->alarm = 0;
+    p->leader = 0;
 
-    p->ldt[0] = current->ldt[0];
-    p->ldt[1] = current->ldt[1];
-    p->ldt[2] = current->ldt[2];
+    p->utime = p->stime = 0;
+    p->cutime = p->cstime = 0;
+    p->start_time = jiffies;
 
     p->tss.back_link = 0;
     p->tss.esp0 = PAGE_SIZE + (long)p - 8;
     p->tss.ss0 = 0x10;
-    p->tss.cr3 = current->tss.cr3;
     p->tss.eip = eip;
     p->tss.eflags = eflags;
     p->tss.eax = 0;
@@ -102,32 +104,22 @@ int copy_process(int nr,long ebp,long edi,long esi,long gs,long none,
     }
 
     for (i = 0; i < NR_OPEN; i++) {
-        p->filp[i] = current->filp[i];
         if ((f = p->filp[i]))
             f->f_count++;
     }
 
-    p->tty = current->tty;
-    p->umask = current->umask;
-
-    p->pwd = current->pwd;
     if (current->pwd)
         current->pwd->i_count++;
 
-    p->root = current->root;
     if (current->root)
         current->root->i_count++;
 
-    p->executable = current->executable;
     if (current->executable)
         current->executable->i_count++;
 
-    p->library = current->library;
     if (current->library)
         current->library->i_count++;
 
-    p->close_on_exec = current->close_on_exec;
-
     set_tss_desc(gdt+(nr<<1)+FIRST_TSS_ENTRY,&(p->tss));
     set_ldt_desc(gdt+(nr<<1)+FIRST_LDT_ENTRY,&(p->ldt));
 
diff --git a/kernel/signal.c b/kernel/signal.c
index eb451a9..50fb51f 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -73,9 +73,11 @@ int do_signal(long signr,long eax,long ebx, long ecx, long edx, long orig_eax,
 
     unsigned long * tmp_esp;
 
+    /*
     printk("pid: %d, signr: %x, eax=%d, oeax = %d, int=%d\n",
             current->pid, signr, eax, orig_eax,
             sa->sa_flags & SA_INTERRUPT);
+            */
 
     if ((orig_eax != -1) &&
             ((eax == -ERESTARTSYS) || (eax == -ERESTARTNOINTR))) {
-- 
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