add CERT exp15-c check (#1897)

* add CERT exp15-c check

* fix false positive

* remove useless check

* fine tune check and test

addons/cert.py

@@ -154,6 +154,15 @@ def exp42(data):
                 token, 'style', "Comparison of struct padding data " +
                 "(fix either by packing the struct using '#pragma pack' or by rewriting the comparison)", 'EXP42-C')
 
+# EXP15-C
+# Do not place a semicolon on the same line as an if, for or while statement
+def exp15(data):
+    for scope in data.scopes:
+        if scope.type in ('If', 'For', 'While'):
+            token = scope.bodyStart.next 
+            if token.str==';' and token.linenr==scope.bodyStart.linenr:
+                reportError(token, 'style', 'Do not place a semicolon on the same line as an IF, FOR or WHILE', 'EXP15-C')
+
 
 # EXP46-C
 # Do not use a bitwise operator with a Boolean-like operand
@@ -293,6 +302,7 @@ for arg in sys.argv[1:]:
         exp05(cfg)
         exp42(cfg)
         exp46(cfg)
+        exp15(cfg)
         int31(cfg, data.platform)
         str03(cfg)
         str05(cfg)

addons/test/cert-test.c

@@ -61,6 +61,18 @@ void msc30()
     int a = rand;
 }
 
+void exp15()
+{
+    int x=5, y=7;
+
+    if(x==y);                            //cert-EXP15-C
+    {
+        printf("not working\n");
+    }
+    if(x)
+        ;
+}
+
 void str03()
 {
     char *string_data=(char*)malloc(16);
@@ -72,8 +84,14 @@ void str03()
 
 void str05()
 {
-    char *str1 = "abc";         //cert-STR05-C
-    wchar_t *str2  = L"hello";  //cert-STR05-C
+    int x=5, y=7;
+
+    if(x==y);                            //cert-EXP15-C
+    {
+        printf("not working\n");
+    }
+    if(x)
+        ;
 }
 
 void str07(char *buf, const char *newBuf)