testmemleak.cpp

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

    }

    void class9()
    {
        check("class A\n"
              "{\n"
              "public:\n"
              "	   int * p;\n"
              "	   A();\n"
              "	   ~A();\n"
              "};\n"
              "\n"
              "A::A()\n"
              "{ p = new int; }\n"
              "\n"
              "A::~A()\n"
              "{ delete (p); }\n", true);
        ASSERT_EQUALS("", errout.str());
    }





    void throw1()
    {
        check("void foo()\n"
              "{\n"
              "    char *str = new char[10];\n"
              "    if ( ! abc )\n"
              "        throw 123;\n"
              "    delete [] str;\n"
              "}\n");

        ASSERT_EQUALS(std::string("[test.cpp:5]: (error) Memory leak: str\n"), errout.str());
    }

    void throw2()
    {
        check("void foo()\n"
              "{\n"
              "    char *str = 0;\n"
              "    try\n"
              "    {\n"
              "        str = new char[100];\n"
              "        if ( somecondition )\n"
              "            throw exception;\n"
              "        delete [] str;\n"
              "    }\n"
              "    catch ( ... )\n"
              "    {\n"
              "        delete [] str;\n"
              "    }\n"
              "}\n");

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




    void linux_list_1()
    {
        check("struct AB\n"
              "{\n"
              "    int a;\n"
              "    int b;\n"
              "};\n"
              "void foo()\n"
              "{\n"
              "    struct AB *ab = new AB;\n"
              "    func(&ab->a);\n"
              "}\n");

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



    void sizeof1()
    {
        check("void f()\n"
              "{\n"
              "    struct s_t s1;\n"
              "    struct s_t cont *p = &s1;\n"
              "    struct s_t *s2;\n"
              "\n"
              "    memset(p, 0, sizeof(*p));\n"
              "\n"
              "    s2 = (struct s_t *) malloc(sizeof(*s2));\n"
              "\n"
              "    if (s2->value != 0)\n"
              "        return;\n"
              "\n"
              "    free(s2);\n"
              "\n"
              "    return;\n"
              "}\n");

        std::string err(errout.str());

        ASSERT_EQUALS(std::string("[test.cpp:12]: (error) Memory leak: s2\n"), err);
    }


    void realloc1()
    {
        check("void foo()\n"
              "{\n"
              "    char *a = (char *)malloc(10);\n"
              "    a = realloc(a, 100);\n"
              "}\n");
        ASSERT_EQUALS(std::string("[test.cpp:5]: (error) Memory leak: a\n"), errout.str());
    }

    void realloc2()
    {
        check("void foo()\n"
              "{\n"
              "    char *a = (char *)malloc(10);\n"
              "    a = (char *)realloc(a, 100);\n"
              "    free(a);\n"
              "}\n");

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


    void assign()
    {
        check("void foo()\n"
              "{\n"
              "    char *a = (char *)malloc(10);\n"
              "    a = 0;\n"
              "    free(a);\n"
              "}\n");

        ASSERT_EQUALS(std::string("[test.cpp:4]: (error) Memory leak: a\n"), errout.str());

        check("void foo()\n"
              "{\n"
              "    char *a = (char *)malloc(10);\n"
              "    char *p = a;\n"
              "    free(p);\n"
              "}\n");

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

        check("void foo()\n"
              "{\n"
              "    char *a = (char *)malloc(10);\n"
              "    char *p = a + 1;\n"
              "    free(p);\n"
              "}\n");

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

        check("void foo()\n"
              "{\n"
              "    char *a = (char *)malloc(10);\n"
              "    a += 10;\n"
              "    free(a - 10);\n"
              "}\n");

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

        check("void foo()\n"
              "{\n"
              "    char *a = (char *)malloc(10);\n"
              "    a = (void *)a + 10;\n"
              "    free(a - 10);\n"
              "}\n");

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

        check("void foo()\n"
              "{\n"
              "    char *a = new char[100];\n"
              "    list += a;\n"
              "}\n");

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


    void varid()
    {
        check("void foo()\n"
              "{\n"
              "    char *p = malloc(100);\n"
              "    {\n"
              "        char *p = 0;\n"
              "        delete p;\n"
              "    }\n"
              "    free(p);\n"
              "}\n");
        ASSERT_EQUALS(std::string(""), errout.str());
    }

    void cast1()
    {
        check("void foo()\n"
              "{\n"
              "    char *a = reinterpret_cast<char *>(malloc(10));\n"
              "}\n");

        ASSERT_EQUALS(std::string("[test.cpp:4]: (error) Memory leak: a\n"), errout.str());
    }

    void cast2()
    {
        check("void foo()\n"
              "{\n"
              "    char *a = malloc(10);\n"
              "    free((void *)a);\n"
              "}\n");

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

    void cast3()
    {
        check("void foo()\n"
              "{\n"
              "    char *a = malloc(10);\n"
              "    free(reinterpret_cast<void *>(a));\n"
              "}\n");

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





    void structmember1()
    {
        check("void f()\n"
              "{\n"
              "    struct ABC *abc = new ABC;\n"
              "    abc->a = new char[100];\n"
              "    delete abc;\n"
              "}\n");

        ASSERT_EQUALS(std::string("[test.cpp:5]: (error) Memory leak: abc.a\n"), errout.str());
    }




    void dealloc_use_1()
    {
        check("void f()\n"
              "{\n"
              "    char *s = new char[100];\n"
              "    delete [] s;\n"
              "    p = s;\n"
              "}\n");
        ASSERT_EQUALS(std::string("[test.cpp:5]: (error) Using 's' after it is deallocated / released\n"), errout.str());
    }

    void dealloc_use_2()
    {
        check("void f()\n"
              "{\n"
              "    char *str;\n"
              "    free(str);\n"
              "    foo(&str);\n"
              "}\n");
        ASSERT_EQUALS(std::string(""), errout.str());
    }

    void dealloc_use_3()
    {
        check("void foo()\n"
              "{\n"
              "    char *str = 0;\n"
              "    free(str);\n"
              "    f1(&str);\n"
              "    f2(str);\n"
              "}\n");
        ASSERT_EQUALS(std::string(""), errout.str());
    }

    void dealloc_use_4()
    {
        check("static void ReadDir(DIR *d)\n"
              "{\n"
              "    DIR *subdir = OpenDir();\n"
              "    ReadDir( subdir );\n"
              "    closedir(subdir);\n"
              "}\n");
        ASSERT_EQUALS(std::string(""), errout.str());
    }

    void dealloc_use_5()
    {
        check("void foo()\n"
              "{\n"
              "    char *str = 0;\n"
              "    free(str);\n"
              "    char c = str[10];\n"
              "}\n");
        ASSERT_EQUALS(std::string("[test.cpp:5]: (error) Using 'str' after it is deallocated / released\n"), errout.str());
    }

    void dealloc_use_6()
    {
        check("void foo()\n"
              "{\n"
              "    char *str = 0;\n"
              "    free(str);\n"
              "    printf(\"free %x\", str);\n"
              "}\n");
        ASSERT_EQUALS(std::string(""), errout.str());
    }

    void dealloc_use_7()
    {
        check("void foo()\n"
              "{\n"
              "    char *str = new char[10];\n"
              "    delete [] str;\n"
              "    str[10] = 0;\n"
              "}\n");
        ASSERT_EQUALS(std::string("[test.cpp:5]: (error) Using 'str' after it is deallocated / released\n"), errout.str());
    }


    void freefree1()
    {
        check("void foo()\n"
              "{\n"
              "    char *str = malloc(100);\n"
              "    free(str);\n"
              "    free(str);\n"
              "}\n");
        ASSERT_EQUALS(std::string("[test.cpp:5]: (error) Deallocating a deallocated pointer: str\n"), errout.str());
    }

    void freefree2()
    {
        check("void foo()\n"
              "{\n"
              "    FILE *fd = fopen(\"test.txt\", \"wb\");\n"
              "    fprintf(fd, \"test\");\n"
              "    fclose(fd);\n"
              "}\n");
        ASSERT_EQUALS(std::string(""), errout.str());
    }

    void strcat_result_assignment()
    {
        check("void foo()\n"
              "{\n"
              "    char *p = malloc(10);\n"
              "    p[0] = 0;\n"
              "    p = strcat( p, \"a\" );\n"
              "    free( p );\n"
              "    return 0;\n"
              "}");
        ASSERT_EQUALS(std::string(""), errout.str());
    }



    void all1()
    {
        check("void foo()\n"
              "{\n"
              "    Fred *f = new Fred;\n"
              "}\n", false);
        ASSERT_EQUALS(std::string(""), errout.str());

        check("void foo()\n"
              "{\n"
              "    Fred *f = new Fred;\n"
              "}\n", true);
        ASSERT_EQUALS(std::string("[test.cpp:4]: (all) Memory leak: f\n"), errout.str());
    }



    void malloc_constant_1()
    {
        check("void foo()\n"
              "{\n"
              "    int *p = malloc(3);\n"
              "    free(p);\n"
              "}\n", false);
        ASSERT_EQUALS(std::string("[test.cpp:3]: (error) The given size 3 is mismatching\n"), errout.str());
    }



    void unknownFunction1()
    {
        check("void foo()\n"
              "{\n"
              "    int *p = new int[100];\n"
              "    if (abc)\n"
              "    {\n"
              "        delete [] p;\n"
              "        ThrowException();\n"
              "    }\n"
              "    delete [] p;\n"
              "}\n");
        ASSERT_EQUALS("", errout.str());
    }

    void unknownFunction2()
    {
        check("void foo()\n"
              "{\n"
              "    int *p = new int[100];\n"
              "    if (abc)\n"
              "    {\n"
              "        delete [] p;\n"
              "        ThrowException();\n"
              "    }\n"
              "}\n");
        ASSERT_EQUALS("[test.cpp:9]: (error) Memory leak: p\n", errout.str());
    }

    void unknownFunction3()
    {
        check("void foo()\n"
              "{\n"
              "    int *p = new int[100];\n"
              "    ThrowException();\n"
              "}\n");
        ASSERT_EQUALS("[test.cpp:5]: (error) Memory leak: p\n", errout.str());
    }



    void checkvcl(const char code[], const char _autoDealloc[])
    {
        // 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 = true;

        {
            std::istringstream istr(_autoDealloc);
            settings.autoDealloc(istr);
        }

        CheckMemoryLeakClass checkMemoryLeak(&tokenizer, settings, this);
        checkMemoryLeak.CheckMemoryLeak();
    }



    void vcl1()
    {
        checkvcl("void Form1::foo()\n"
                 "{\n"
                 "    TEdit *Edit1 = new TEdit(this);\n"
                 "}\n", "TEdit\n");
        ASSERT_EQUALS("", errout.str());
    }


    void vcl2()
    {
        checkvcl("class Fred\n"
                 "{\n"
                 "private:\n"
                 "    TButton *button;\n"
                 "public:\n"
                 "    Fred();\n"
                 "};\n"
                 "\n"
                 "Fred::Fred()\n"
                 "{\n"
                 "    button = new TButton(this);\n"
                 "}\n", "TButton\n");
        ASSERT_EQUALS("", errout.str());
    }
};

REGISTER_TEST(TestMemleak)