testmemleak.cpp

cppcheck is a static C/C++ code analyzer that checks for memory leaks, mismatching allocation-deallo

/*
 * Cppcheck - A tool for static C/C++ code analysis
 * Copyright (C) 2007-2009 Daniel Marjamäki, Reijo Tomperi, Nicolas Le Cam,
 * Leandro Penz, Kimmo Varis, Vesa Pikki
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/
 */





#include "../src/tokenize.h"
#include "../src/checkmemoryleak.h"
#include "testsuite.h"

#include <iostream>
#include <sstream>

extern std::ostringstream errout;

class TestMemleak : public TestFixture
{
public:
    TestMemleak() : TestFixture("TestMemleak")
    { }

private:
    void check(const char code[], bool showAll = false)
    {
        // Tokenize..
        Tokenizer tokenizer;
        std::istringstream istr(code);
        tokenizer.tokenize(istr, "test.cpp");
        tokenizer.setVarId();
        tokenizer.simplifyTokenList();

        // Clear the error buffer..
        errout.str("");

        // Check for memory leaks..
        Settings settings;
        settings._debug = true;
        settings._showAll = showAll;
        tokenizer.fillFunctionList();
        CheckMemoryLeakClass checkMemoryLeak(&tokenizer, settings, this);
        checkMemoryLeak.CheckMemoryLeak();
    }

    void run()
    {
        TEST_CASE(simple1);
        TEST_CASE(simple2);
        TEST_CASE(simple3);
        TEST_CASE(simple4);
        TEST_CASE(simple5);
        TEST_CASE(simple6);
        TEST_CASE(simple7);
        TEST_CASE(simple8);
        TEST_CASE(simple9);     // Bug 2435468 - member function "free"
        TEST_CASE(simple10);    // fclose in a if condition

        TEST_CASE(alloc_alloc_1);

        TEST_CASE(use1);
        TEST_CASE(use2);

        TEST_CASE(ifelse1);
        TEST_CASE(ifelse2);
        TEST_CASE(ifelse3);
        TEST_CASE(ifelse4);
        TEST_CASE(ifelse5);
        TEST_CASE(ifelse6);
        TEST_CASE(ifelse7);
        TEST_CASE(ifelse8);
        TEST_CASE(ifelse9);
        TEST_CASE(ifelse10);

        TEST_CASE(if1);
        TEST_CASE(if2);
        TEST_CASE(if3);
        TEST_CASE(if4);
        TEST_CASE(if5);
        TEST_CASE(if6);     // Bug 2432631
        TEST_CASE(if7);     // Bug 2401436
        TEST_CASE(if8);     // Bug 2458532
        // TODO TEST_CASE( if9 );   // if (realloc)
        TEST_CASE(if10);            // else if (realloc)
        TEST_CASE(if11);

        TEST_CASE(forwhile1);
        TEST_CASE(forwhile2);
        TEST_CASE(forwhile3);
        TEST_CASE(forwhile4);
        TEST_CASE(forwhile5);
        TEST_CASE(forwhile6);
        TEST_CASE(forwhile7);
        TEST_CASE(forwhile8);       // Bug 2429936
        TEST_CASE(forwhile9);
        TEST_CASE(forwhile10);

        TEST_CASE(dowhile1);

        TEST_CASE(switch1);
        TEST_CASE(switch2);
        TEST_CASE(switch3);

        TEST_CASE(ret1);
        TEST_CASE(ret2);
        TEST_CASE(ret3);
        TEST_CASE(ret4);
        TEST_CASE(ret5);        // Bug 2458436 - return use
        TEST_CASE(ret6);
        TEST_CASE(ret7);

        TEST_CASE(mismatch1);
        TEST_CASE(mismatch2);
        TEST_CASE(mismatch3);
        TEST_CASE(mismatch4);

        TEST_CASE(func1);
        TEST_CASE(func2);
        TEST_CASE(func3);
        TEST_CASE(func4);
        TEST_CASE(func5);
        TEST_CASE(func6);
        // TODO TEST_CASE( func7 );
        TEST_CASE(func8);       // Using callback
        TEST_CASE(func9);       // Embedding the function call in a if-condition
        TEST_CASE(func10);      // Bug 2458510 - Function pointer
        TEST_CASE(func11);      // Bug 2458510 - Function pointer
        TEST_CASE(func12);
        TEST_CASE(func13);

        TEST_CASE(class1);
        TEST_CASE(class2);
        // TODO TEST_CASE( class3 );
        TEST_CASE(class4);
        TEST_CASE(class5);
        TEST_CASE(class6);
        TEST_CASE(class7);
        TEST_CASE(class8);
        TEST_CASE(class9);

        TEST_CASE(throw1);
        TEST_CASE(throw2);

        TEST_CASE(linux_list_1);

        TEST_CASE(sizeof1);

        TEST_CASE(realloc1);
        TEST_CASE(realloc2);

        TEST_CASE(assign);

        // TODO TEST_CASE( varid );

        TEST_CASE(cast1);
        TEST_CASE(cast2);
        TEST_CASE(cast3);


        // TODO TEST_CASE( structmember1 );

        TEST_CASE(dealloc_use_1);       // Deallocate and then use memory
        TEST_CASE(dealloc_use_2);       // Deallocate and then use memory. No error if "use" is &var
        TEST_CASE(dealloc_use_3);       // Deallocate and then use memory. No error
        TEST_CASE(dealloc_use_4);
        TEST_CASE(dealloc_use_5);
        TEST_CASE(dealloc_use_6);
        TEST_CASE(dealloc_use_7);

        // free a free'd pointer
        TEST_CASE(freefree1);
        TEST_CASE(freefree2);
        TEST_CASE(strcat_result_assignment);

        TEST_CASE(all1);                // Extra checking when --all is given

        TEST_CASE(malloc_constant_1);     // Check that the malloc constant matches the type

        // Calls to unknown functions.. they may throw exception, quit the program, etc
        TEST_CASE(unknownFunction1);
        TEST_CASE(unknownFunction2);
        TEST_CASE(unknownFunction3);

        // VCL..
        TEST_CASE(vcl1);
        TEST_CASE(vcl2);
    }



    void simple1()
    {
        check("void f()\n"
              "{\n"
              "    int *a = new int[10];\n"
              "}\n");
        ASSERT_EQUALS(std::string("[test.cpp:4]: (error) Memory leak: a\n"), errout.str());
    }

    void simple2()
    {
        check("Fred *NewFred()\n"
              "{\n"
              "    Fred *f = new Fred;\n"
              "    return f;\n"
              "}\n");
        ASSERT_EQUALS(std::string(""), errout.str());
    }

    void simple3()
    {
        check("static char *f()\n"
              "{\n"
              "    char *s = new char[100];\n"
              "    return (char *)s;\n"
              "}\n");
        ASSERT_EQUALS(std::string(""), errout.str());
    }


    void simple4()
    {
        check("static char *f()\n"
              "{\n"
              "    char *s = new char[100];\n"
              "    return 0;\n"
              "}\n");
        ASSERT_EQUALS(std::string("[test.cpp:4]: (error) Memory leak: s\n"), errout.str());
    }


    void simple5()
    {
        check("static char *f()\n"
              "{\n"
              "    struct *str = new strlist;\n"
              "    return &str->s;\n"
              "}\n");
        ASSERT_EQUALS(std::string(""), errout.str());
    }


    void simple6()
    {
        check("static void f()\n"
              "{\n"
              "    char *str = strdup(\"hello\");\n"
              "    char *str2 = (char *)str;\n"
              "    free(str2);\n"
              "}\n");
        ASSERT_EQUALS(std::string(""), errout.str());
    }


    void simple7()
    {
        // A garbage collector may delete f automaticly
        check("class Fred;\n"
              "void foo()\n"
              "{\n"
              "    Fred *f = new Fred;\n"
              "}\n");
        ASSERT_EQUALS(std::string(""), errout.str());
    }


    void simple8()
    {
        check("char * foo ()\n"
              "{\n"
              "    char *str = strdup(\"abc\");\n"
              "    if (somecondition)\n"
              "        for (i = 0; i < 2; i++)\n"
              "        { }\n"
              "    return str;\n"
              "}\n");
        ASSERT_EQUALS(std::string(""), errout.str());
    }


    void simple9()
    {
        check("void foo()\n"
              "{\n"
              "    MyClass *c = new MyClass();\n"
              "    c->free(c);\n"
              "    delete c;\n"
              "}\n");
        ASSERT_EQUALS(std::string(""), errout.str());
    }

    void simple10()
    {
        check("void foo()\n"
              "{\n"
              "    FILE * f = fopen(fname, str);\n"
              "    if ( fclose(f) != NULL );\n"
              "}\n");
        ASSERT_EQUALS(std::string(""), errout.str());
    }




    void alloc_alloc_1()
    {
        check("void foo()\n"
              "{\n"
              "    char *str;\n"
              "    str = new char[10];\n"
              "    str = new char[20];\n"
              "    delete [] str;\n"
              "}\n");
        ASSERT_EQUALS(std::string("[test.cpp:5]: (error) Memory leak: str\n"), errout.str());
    }






    void use1()
    {
        check("void foo()\n"
              "{\n"
              "    char *str;\n"
              "    if (somecondition)\n"
              "        str = strdup(\"abc\");\n"
              "    if (somecondition)\n"
              "        DeleteString(str);\n"
              "}\n");

        ASSERT_EQUALS(std::string(""), errout.str());
    }


    void use2()
    {
        check("void foo()\n"
              "{\n"
              "    char *str = strdup(\"abc\");\n"
              "    if ( abc ) { memset(str, 0, 3); }\n"
              "    *somestr = str;\n"
              "}\n");

        ASSERT_EQUALS(std::string(""), errout.str());
    }






    void ifelse1()
    {
        check("void f()\n"
              "{\n"
              "    int *a = new int[10];\n"
              "    if (a)\n"
              "    {\n"
              "        delete [] a;\n"
              "    }\n"
              "}\n");
        ASSERT_EQUALS(std::string(""), errout.str());
    }


    void ifelse2()
    {
        check("void f()\n"
              "{\n"
              "    char *str = strdup(\"hello\");\n"
              "    if (somecondition)\n"
              "    {\n"
              "        return;\n"
              "    }\n"
              "    free(str);\n"
              "}\n");
        ASSERT_EQUALS(std::string("[test.cpp:6]: (error) Memory leak: str\n"), errout.str());
    }


    void ifelse3()
    {
        check("void f()\n"
              "{\n"
              "    char *str = strdup(\"hello\");\n"
              "    if (a==b)\n"
              "    {\n"
              "        free(str);\n"
              "        return;\n"
              "    }\n"
              "}\n");
        ASSERT_EQUALS(std::string(""), errout.str());

        check("void f()\n"
              "{\n"
              "    char *str = strdup(\"hello\");\n"
              "    if (a==b)\n"
              "    {\n"
              "        free(str);\n"
              "        return;\n"
              "    }\n"
              "}\n", true);
        ASSERT_EQUALS(std::string("[test.cpp:9]: (all) Memory leak: str\n"), errout.str());
    }


    void ifelse4()
    {
        check("void f()\n"
              "{\n"
              "    char *str = new char[10];\n"
              "    if (a==b)\n"
              "    {\n"
              "        delete [] str;\n"
              "        return;\n"
              "    }\n"
              "    delete [] str;\n"
              "}\n");
        ASSERT_EQUALS(std::string(""), errout.str());
    }


    void ifelse5()
    {
        check("void f()\n"
              "{\n"
              "    char *str;\n"
              "    if (somecondition)\n"
              "    {\n"
              "        str = new char[100];\n"
              "    }\n"
              "    else\n"
              "    {\n"
              "        return;\n"
              "    }\n"
              "    delete [] str;\n"
              "}\n");
        ASSERT_EQUALS(std::string(""), errout.str());
    }


    void ifelse6()
    {
        check("static char *f()\n"
              "{\n"
              "    char *s = new char[100];\n"
              "    if ( a == b )\n"
              "    {\n"
              "        return s;\n"
              "    }\n"
              "    return NULL;\n"
              "}\n");
        ASSERT_EQUALS(std::string("[test.cpp:8]: (error) Memory leak: s\n"), errout.str());
    }


    void ifelse7()
    {
        check("static char *f()\n"
              "{\n"
              "    char *s;\n"
              "    if ( abc )\n"
              "    {\n"
              "        s = new char[10];\n"
              "    }\n"
              "    return s;\n"
              "}\n");
        ASSERT_EQUALS(std::string(""), errout.str());
    }


    void ifelse8()
    {
        check("static char *f()\n"
              "{\n"
              "    char *s = new char[10];\n"
              "    if ( s )\n"
              "    {\n"
              "        return s;\n"
              "    }\n"
              "    return 0;\n"
              "}\n");