Fix FP with embedded zeros (#4226)

* Partial fix for #11137 FN: invalidFunctionArgStr printf argument

* Typo

* Remove <strz>, suppressions

* Add suppresion, remove <strz>

* Add suppressions

* Fix FP with embedded zeros

* Merge

Author: chrchr-github

lib/checkfunctions.cpp

@@ -174,7 +174,7 @@ void CheckFunctions::invalidFunctionUsage()
                             const Token* strTok = varTok->getValueTokenMinStrSize(mSettings);
                             if (strTok) {
                                 const int strSize = Token::getStrArraySize(strTok);
-                                if (strSize > count)
+                                if (strSize > count && strTok->str().find('\0') == std::string::npos)
                                     invalidFunctionArgStrError(argtok, functionToken->str(), argnr);
                             }
                         }

test/testfunctions.cpp

@@ -729,6 +729,12 @@ class TestFunctions : public TestFixture {
               "    strcat(dest, if_name);\n"
               "}\n");
         ASSERT_EQUALS("", errout.str());
+
+        check("int f() {\n"
+              "    const char c[3] = \"ab\\0\";\n"
+              "    return strlen(c);\n"
+              "}\n");
+        ASSERT_EQUALS("", errout.str());
     }
 
     void mathfunctionCall_sqrt() {