diff --git a/include/syscap_tool.h b/include/syscap_tool.h
index 42ff366d0dc97588efefe5975f9383852217adcb..2d129877a8ee2528cdc66af4a9bdca51bd8b712b 100644
--- a/include/syscap_tool.h
+++ b/include/syscap_tool.h
@@ -36,7 +36,7 @@ int32_t RPCIDDecode(char *inputFile, char *outputPath);
 int32_t EncodeRpcidscToString(char *inputFile, char *outDirPath);
 /* in: pcidFile, rpcidFile */
 int32_t ComparePcidWithRpcidString(char *pcidFile, char *rpcidFile);
-int32_t SeparateSyscapFromString(char *input, uint32_t *osArray, uint32_t osArraySize,
+int32_t SeparateSyscapFromString(const char *inputString, uint32_t *osArray, uint32_t osArraySize,
                                  char **priSyscap, uint32_t *priSyscapLen);
 
 #ifdef __cplusplus
diff --git a/interfaces/inner_api/syscap_interface.c b/interfaces/inner_api/syscap_interface.c
index 544c5958d840fc17357d7f9644c48906c02e57ca..0e2ece220051945e501b1b8a50e092e249e790bb 100644
--- a/interfaces/inner_api/syscap_interface.c
+++ b/interfaces/inner_api/syscap_interface.c
@@ -378,7 +378,7 @@ FREE_SYSCAP_OUT:
     return ret;
 }
 
-static int32_t CheckRpcidFormat(const char *inputFile, char **Buffer, uint32_t *Len)
+static int32_t CheckRpcidFormat(const char *inputFile, char **buffer, uint32_t *Len)
 {
     uint32_t bufferLen;
     uint16_t sysCaptype, sysCapLength;
@@ -409,7 +409,7 @@ static int32_t CheckRpcidFormat(const char *inputFile, char **Buffer, uint32_t *
         return -1;
     }
 
-    *Buffer = contextBuffer;
+    *buffer = contextBuffer;
     *Len = bufferLen;
     return 0;
 }
@@ -498,8 +498,8 @@ char *DecodeRpcidToStringFormat(const char *inputFile)
         goto FREE_MALLOC_PRISYSCAP;
     }
 
-    uint16_t outBufferLen = U32_TO_STR_MAX_LEN * RPCID_OUT_BUFFER
-                            + SINGLE_SYSCAP_LEN * indexPri;
+    uint16_t outBufferLen = U32_TO_STR_MAX_LEN * RPCID_OUT_BUFFER +
+                            SINGLE_SYSCAP_LEN * indexPri;
     outBuffer = (char *)malloc(outBufferLen);
     if (outBuffer == NULL) {
         PRINT_ERR("malloc(%u) failed.\n", outBufferLen);
@@ -545,12 +545,12 @@ FREE_CONTEXT_OUT:
     return outBuffer;
 }
 
-int32_t ComparePcidString(char *pcidString, char *rpcidString, CompareError *result)
+int32_t ComparePcidString(const char *pcidString, const char *rpcidString, CompareError *result)
 {
     int32_t ret;
-    int32_t versionFlag = 0;
-    int32_t ossyscapFlag = 0;
-    int32_t prisyscapFlag = 0;
+    uint16_t versionFlag = 0;
+    uint16_t ossyscapFlag = 0;
+    uint16_t prisyscapFlag = 0;
     char *pcidPriSyscap = NULL;
     char *rpcidPriSyscap = NULL;
     bool priSysFound;
@@ -631,10 +631,10 @@ int32_t ComparePcidString(char *pcidString, char *rpcidString, CompareError *res
         priSysFound = false;
     }
 
-    if (versionFlag) {
+    if (versionFlag > 0) {
         ret |= 0x1 << 0;
     }
-    if (ossyscapFlag || prisyscapFlag) {
+    if (ossyscapFlag > 0 || prisyscapFlag > 0) {
         ret |= 0x1 << 1;
         result->missSyscapNum = ossyscapFlag + prisyscapFlag;
     }
diff --git a/interfaces/inner_api/syscap_interface.h b/interfaces/inner_api/syscap_interface.h
index c48bbf2acc35c2b04f1f61eb8118a00826650886..be48c6e918986178e7ed97b89f62e8716464779a 100644
--- a/interfaces/inner_api/syscap_interface.h
+++ b/interfaces/inner_api/syscap_interface.h
@@ -67,7 +67,7 @@ char *DecodeRpcidToStringFormat(const char *inputFile);
  *                            result.syscap[] is the array of points to syscap strings.
  *      free variable result by function FreeCompareError.
  */
-int32_t ComparePcidString(char *pcidString, char *rpcidString, CompareError *result);
+int32_t ComparePcidString(const char *pcidString, const char *rpcidString, CompareError *result);
 int32_t FreeCompareError(CompareError *result);
 
 #ifdef __cplusplus
diff --git a/src/syscap_tool.c b/src/syscap_tool.c
index 9fba6b9a542d4f6294c9d269f0f055af4c520a35..f65091ca39dab4b6660108af4148e1cffc2f6bf7 100644
--- a/src/syscap_tool.c
+++ b/src/syscap_tool.c
@@ -564,11 +564,12 @@ FREE_CONTEXT_OUT:
     return ret;
 }
 
-int32_t SeparateSyscapFromString(char *input, uint32_t *osArray, uint32_t osArraySize,
+int32_t SeparateSyscapFromString(const char *inputString, uint32_t *osArray, uint32_t osArraySize,
                                  char **priSyscap, uint32_t *priSyscapLen)
 {
     int32_t ret = 0;
-    uint32_t i, inputLen;
+    uint32_t i;
+    uint32_t inputLen = strlen(inputString);
     uint32_t count = 0;
     char *temp = NULL;
     char *tok = NULL;
@@ -578,11 +579,26 @@ int32_t SeparateSyscapFromString(char *input, uint32_t *osArray, uint32_t osArra
         return -1;
     }
 
-    inputLen = strlen(input);
+    // copy to temp string input
+    char *input = (char *)malloc(strlen(inputString) + 1);
+    if (input == NULL) {
+        PRINT_ERR("malloc failed.\n");
+        return -1;
+    }
+    ret = strcpy_s(input, inputLen + 1, inputString);
+    if (ret != EOK) {
+        PRINT_ERR("strcpy_s failed.\n");
+        free(input);
+        return -1;
+    }
+    input[inputLen] = '\0';
+
+    // get os syscap data
     for (i = 0; i < PCID_OUT_BUFFER; i++) {
         ret = sscanf_s(input, "%u,%s", &osArray[i], input, inputLen);
         if (ret == -1) {
             PRINT_ERR("sscanf_s failed.\n");
+            free(input);
             return -1;
         }
     }
@@ -603,6 +619,7 @@ int32_t SeparateSyscapFromString(char *input, uint32_t *osArray, uint32_t osArra
     char *priSysCapOut = (char *)malloc(SINGLE_SYSCAP_LEN * count);
     if (priSysCapOut == NULL) {
         PRINT_ERR("sscanf_s failed.\n");
+        free(input);
         return -1;
     }
     (void)memset_s(priSysCapOut, SINGLE_SYSCAP_LEN * count, 0, SINGLE_SYSCAP_LEN * count);
@@ -614,6 +631,7 @@ int32_t SeparateSyscapFromString(char *input, uint32_t *osArray, uint32_t osArra
                         temp, SINGLE_SYSCAP_LEN - 1);
         if (ret != EOK) {
             PRINT_ERR("strncpy_s failed.\n");
+            free(input);
             free(private);
             return -1;
         }
@@ -625,6 +643,7 @@ int32_t SeparateSyscapFromString(char *input, uint32_t *osArray, uint32_t osArra
     *priSyscapLen = count;
 
 SKIP_PRI_SYSCAP:
+    free(input);
     return 0;
 }
 
@@ -667,7 +686,7 @@ int32_t ComparePcidWithRpcidString(char *pcidFile, char *rpcidFile)
     uint16_t pcidVersion = NtohsInter(((PCIDMain *)pcidOsAarry)->apiVersion);
     uint16_t rpcidVersion = NtohsInter(((RPCIDHead *)rpcidOsAarry)->apiVersion);
     if (pcidVersion < rpcidVersion) {
-        PRINT_ERR("Pcid version(%u) less than rpcid version(%u).\n", pcidVersion, rpcidVersion);
+        printf("ERROR: Pcid version(%u) less than rpcid version(%u).\n", pcidVersion, rpcidVersion);
         versionFlag = 1;
     }
     // compare os syscap
diff --git a/test/unittest/common/syscap_codec_test.cpp b/test/unittest/common/syscap_codec_test.cpp
index 71acc76b842d588d42758ab6c6693eab63a10b33..be73036c9860d39c29334a6158ea64ea1ebb18ef 100644
--- a/test/unittest/common/syscap_codec_test.cpp
+++ b/test/unittest/common/syscap_codec_test.cpp
@@ -127,16 +127,16 @@ HWTEST_F(SyscapCodecTest, DecodePrivateSyscap1, TestSize.Level1)
 HWTEST_F(SyscapCodecTest, ComparePcidString, TestSize.Level1)
 {
     CompareError result = {{0}, 0, 0};
-    char pcidString[] = "263168,0,3473408,0,0,0,1634,0,0,0,0,0,0,0,0,0,0,"\
-                        "0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,SystemCapability.vendor.xxxxx3,"\
-                        "SystemCapability.device.xxxxx4";
-    char rpcidString[] = "33588992,1766370052,65536,276824064,0,0,0,0,0,0,"\
-                         "0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,"\
-                         "SystemCapability.vendor.xxxxx1,SystemCapability.device.xxxxx2";
-    char expect[][256] = {"SystemCapability.HiviewDFX.HiChecker",
-                          "SystemCapability.HiviewDFX.HiProfiler.HiDebug",
-                          "SystemCapability.vendor.xxxxx1",
-                          "SystemCapability.device.xxxxx2"};
+    const char pcidString[] = "263168,0,3473408,0,0,0,1634,0,0,0,0,0,0,0,0,0,0,"\
+                              "0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,SystemCapability.vendor.xxxxx3,"\
+                              "SystemCapability.device.xxxxx4";
+    const char rpcidString[] = "33588992,1766370052,65536,276824064,0,0,0,0,0,0,"\
+                               "0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,"\
+                               "SystemCapability.vendor.xxxxx1,SystemCapability.device.xxxxx2";
+    const char expect[][256] = {"SystemCapability.HiviewDFX.HiChecker",
+                                "SystemCapability.HiviewDFX.HiProfiler.HiDebug",
+                                "SystemCapability.vendor.xxxxx1",
+                                "SystemCapability.device.xxxxx2"};
     int32_t ret = ComparePcidString(pcidString, rpcidString, &result);
     EXPECT_EQ(ret, 3);
     EXPECT_EQ(result.targetApiVersion, 7);