memory leak: improved the checking. subfunctions are parsed. redundant conditions are skipped

CheckMemoryLeak.cpp

@@ -83,6 +83,14 @@ static AllocType GetAllocationType( const TOKEN *tok2 )
 
 static AllocType GetDeallocationType( const TOKEN *tok, const char *varnames[] )
 {
+    // Redundant condition..
+    if ( Match(tok, "if ( %var1% )", varnames) )
+    {
+        tok = gettok( tok, 4 );
+        if ( Match(tok,"{") )
+            tok = tok->next;
+    }                               
+
     if ( Match(tok, "delete %var1% ;", varnames) )
         return New;
 
@@ -156,8 +164,84 @@ static void CheckMemoryLeak_CheckScope( const TOKEN *Tok1, const char varname[]
                 dealloc_indentlevel = -1;
         }
 
+        // Check subfunction...
+        if (Alloc != No && Match(tok,"[{};] %var% ("))
+        {
+            const char *funcname = getstr( tok, 1 );
+
+            unsigned int param = 0;
+            for (const TOKEN *tok2 = gettok(tok,2); tok2; tok2 = tok2->next)
+            {
+                if ( tok2->str[0] == ';' )
+                    break;
+                if ( tok2->str[0] == ',' )
+                    param++;
+
+                if ( Match(tok2, "[(,] %var1% [,)]", varnames) )
+                {
+                    // Find function..
+                    const TOKEN *ftok = GetFunctionTokenByName( funcname );
+                    ftok = gettok(ftok,2);
+                    if ( ! ftok )
+                        break;
+
+                    // Goto function parameter..
+                    for ( unsigned int fparam = 0; ftok && fparam < param; ftok = ftok->next )
+                    {
+                        if ( ftok->str[0] == ',' )
+                            ++fparam;
+                    }
+                    for ( ; ftok; ftok = ftok->next )
+                    {
+                        if ( ! Match(ftok,"%var% [,)]") )
+                            continue;
+
+                        const char *paramname[2] = {0};
+                        paramname[0] = ftok->str;
+                        // parse function and check if it deallocates the parameter..
+                        int _indentlevel = 0;
+                        while (_indentlevel>=0 && ftok)
+                        {
+                            if ( ftok->str[0] == '{' )
+                                _indentlevel++;
+                            else if ( ftok->str[0] == '}' )
+                            {
+                                _indentlevel--;
+                                if ( _indentlevel <= 0 )
+                                    break;
+                            }
+
+                            if ( _indentlevel >= 1 )
+                            {
+                                AllocType dealloc = GetDeallocationType(ftok,paramname);
+                                if ( dealloc != No )
+                                {
+                                    if ( Alloc != No && Alloc != dealloc )
+                                    {
+                                        MismatchError( Tok1, varname );
+                                        return;
+                                    }
+
+                                    // Deallocated at same indentlevel as the allocation => no memory leak
+                                    if ( alloc_indentlevel == indentlevel )
+                                        return;
+
+                                    dealloc_indentlevel = indentlevel;
+                                    break;
+                                }
+                            }
+
+                            ftok = ftok->next;
+                        }
+                        break;
+                    }
+                    break;
+                }
+            }
+        }
+
         // for, while set loop level..
-        if ( alloc_indentlevel >= 0 && (Match(tok,"while") || Match(tok,"for")) )
+        if ( Match(tok,"while") || Match(tok,"for") )
             loop_indentlevel.push_back( indentlevel );
 
         // Skip stuff like: if (!var) ...
@@ -247,8 +331,7 @@ static void CheckMemoryLeak_CheckScope( const TOKEN *Tok1, const char varname[]
         // Used..
         //     list.push_back( var1 );
         //     listtail->next = var1;
-        //     foo( var1 );
-        if ( Match( tok, "[=,(] %var1% [,);]", varnames ) )
+        if ( Match( tok, "[=] %var1% [;]", varnames ) )
         {
             return;
         }

tests.cpp

@@ -521,7 +521,7 @@ static void memleak_in_function()
            "    int *a = new int[10];\n"
            "    if (a)\n"
            "    {\n"
-           "        delete a;\n"
+           "        delete [] a;\n"
            "    }\n"
            "}\n";
     check( CheckMemoryLeak, __LINE__, code, "" );
@@ -619,18 +619,6 @@ static void memleak_in_function()
     check( CheckMemoryLeak, __LINE__, code, "" );
 
 
-    /*  TODO
-    code = "void f()\n"
-           "{\n"
-           "    char *str;\n"
-           "    for (int i = 0; i < 10; ++i)\n"
-           "        str = strdup(\"hello\");\n"
-           "    free(str);\n"
-           "}\n";
-    check( CheckMemoryLeak, __LINE__, code, "[test.cpp:5]: Memory leak: str" );
-    */
-
-
     code = "void f()\n"
            "{\n"
            "    for (int i = 0; i < j; i++)\n"
@@ -777,6 +765,18 @@ static void memleak_in_function()
            "    delete p;\n"
            "}\n";
     check( CheckMemoryLeak, __LINE__, code, "[test.cpp:8]: Mismatching allocation and deallocation: p\n" );
+
+
+    code = "static void foo(const char *str)\n"
+           "{ }\n"
+           "\n"
+           "static void f()\n"
+           "{\n"
+           "    char *p = new char[100];\n"
+           "    foo(p);\n"
+           "}\n";
+    check( CheckMemoryLeak, __LINE__, code, "[test.cpp:6]: Memory leak: p\n" );
+
 }
 //---------------------------------------------------------------------------