fix code check warning

Signed-off-by: liduo <liduo29@huawei.com>

src/compression_parser.cpp

@@ -292,6 +292,9 @@ string CompressionParser::ParseJsonStr(const cJSON *node)
         return "";
     }
     char *jsonString = cJSON_Print(node);
+    if (jsonString == nullptr) {
+        return "";
+    }
     string res(jsonString);
     free(jsonString);
     return res;

src/id_defined_parser.cpp

@@ -291,6 +291,10 @@ int64_t IdDefinedParser::GetStartId() const
     }
 
     int64_t id = strtoll(startIdNode->valuestring, nullptr, 16);
+    if (id == 0) {
+        cerr << "Error: id_defined.json 'startId' is not a valid hexadecimal string." << endl;
+        return -1;
+    }
     return id;
 }
 

src/reference_parser.cpp

@@ -88,6 +88,10 @@ uint32_t ReferenceParser::ParseRefInResourceItem(ResourceItem &resourceItem) con
     string data;
     bool update = false;
     if (IsStringOfResourceItem(resType)) {
+        if (resourceItem.GetData() == nullptr) {
+            cerr << "Error: parse ref in resource item failed, data is null." << endl;
+            return RESTOOL_ERROR;
+        }
         data = string(reinterpret_cast<const char *>(resourceItem.GetData()), resourceItem.GetDataLength());
         if (!ParseRefString(data, update)) {
             cerr << "Error: please check JSON file." << NEW_LINE_PATH << resourceItem.GetFilePath() << endl;
@@ -182,6 +186,10 @@ bool ReferenceParser::ParseRefJson(const string &from, const string &to)
 
 bool ReferenceParser::ParseRefResourceItemData(const ResourceItem &resourceItem, string &data, bool &update) const
 {
+    if (resourceItem.GetData() == nullptr) {
+        cerr << "Error: parse ref resource item data failed, data is null." << endl;
+        return false;
+    }
     data = string(reinterpret_cast<const char *>(resourceItem.GetData()), resourceItem.GetDataLength());
     vector<string> contents = ResourceUtil::DecomposeStrings(data);
     if (contents.empty()) {