/* * Cppcheck - A tool for static C/C++ code analysis * Copyright (C) 2007-2012 Daniel Marjamäki and Cppcheck team. * * 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 . */ #include "tokenize.h" #include "checknullpointer.h" #include "testsuite.h" #include extern std::ostringstream errout; class TestNullPointer : public TestFixture { public: TestNullPointer() : TestFixture("TestNullPointer") { } private: void run() { TEST_CASE(nullpointerAfterLoop); TEST_CASE(nullpointer1); TEST_CASE(nullpointer2); TEST_CASE(structDerefAndCheck); // dereferencing struct and then checking if it's null TEST_CASE(pointerDerefAndCheck); TEST_CASE(nullpointer5); // References should not be checked TEST_CASE(nullpointerExecutionPaths); TEST_CASE(nullpointerExecutionPathsLoop); TEST_CASE(nullpointer7); TEST_CASE(nullpointer8); TEST_CASE(nullpointer9); TEST_CASE(nullpointer10); TEST_CASE(nullpointer11); // ticket #2812 TEST_CASE(nullpointer12); // ticket #2470 TEST_CASE(nullpointer13); // ticket #1708 TEST_CASE(nullpointer14); TEST_CASE(pointerCheckAndDeRef); // check if pointer is null and then dereference it TEST_CASE(nullConstantDereference); // Dereference NULL constant TEST_CASE(gcc_statement_expression); // Don't crash TEST_CASE(snprintf_with_zero_size); TEST_CASE(snprintf_with_non_zero_size); TEST_CASE(printf_with_invalid_va_argument); TEST_CASE(scanf_with_invalid_va_argument); TEST_CASE(nullpointer_in_return); TEST_CASE(nullpointer_in_typeid); TEST_CASE(nullpointer_in_for_loop); TEST_CASE(nullpointerDelete); TEST_CASE(nullpointerExit); TEST_CASE(nullpointerStdString); TEST_CASE(functioncall); } void check(const char code[], bool inconclusive = false, bool cpp11 = false) { // Clear the error buffer.. errout.str(""); Settings settings; settings.addEnabled("style"); settings.inconclusive = inconclusive; settings.standards.cpp11 = cpp11; // Tokenize.. Tokenizer tokenizer(&settings, this); std::istringstream istr(code); tokenizer.tokenize(istr, "test.cpp"); // Check for redundant code.. CheckNullPointer checkNullPointer(&tokenizer, &settings, this); checkNullPointer.nullPointer(); tokenizer.simplifyTokenList(); checkNullPointer.nullConstantDereference(); checkNullPointer.executionPaths(); } void nullpointerAfterLoop() { check("int foo(const Token *tok)\n" "{\n" " while (tok);\n" " tok = tok->next();\n" "}\n"); ASSERT_EQUALS("[test.cpp:4]: (error) Possible null pointer dereference: tok - otherwise it is redundant to check if tok is null at line 3\n", errout.str()); // #2681 { const char code[] = "void foo(const Token *tok)\n" "{\n" " while (tok && tok->str() == \"=\")\n" " tok = tok->next();\n" "\n" " if (tok->str() != \";\")\n" " ;\n" "}\n"; check(code, false); // inconclusive=false => no error ASSERT_EQUALS("", errout.str()); check(code, true); // inconclusive=true => error ASSERT_EQUALS("[test.cpp:6]: (error) Possible null pointer dereference: tok - otherwise it is redundant to check if tok is null at line 3\n", errout.str()); } check("void foo()\n" "{\n" " for (const Token *tok = tokens; tok; tok = tok->next())\n" " {\n" " while (tok && tok->str() != \";\")\n" " tok = tok->next();\n" " }\n" "}\n"); ASSERT_EQUALS("[test.cpp:3]: (error) Possible null pointer dereference: tok - otherwise it is redundant to check if tok is null at line 5\n", errout.str()); check("void foo(Token &tok)\n" "{\n" " for (int i = 0; i < tok.size(); i++ )\n" " {\n" " while (!tok)\n" " char c = tok.read();\n" " }\n" "}\n"); ASSERT_EQUALS("", errout.str()); check("void foo()\n" "{\n" " for (const Token *tok = tokens; tok; tok = tok->next())\n" " {\n" " while (tok && tok->str() != \";\")\n" " tok = tok->next();\n" " if( !tok ) break;\n" " }\n" "}\n"); ASSERT_EQUALS("", errout.str()); check("void foo()\n" "{\n" " for (const Token *tok = tokens; tok; tok = tok ? tok->next() : NULL)\n" " {\n" " while (tok && tok->str() != \";\")\n" " tok = tok->next();\n" " }\n" "}\n"); ASSERT_EQUALS("", errout.str()); check("void foo(A*a)\n" "{\n" " switch (a->b()) {\n" " case 1:\n" " while( a ){\n" " a = a->next;\n" " }\n" " break;\n" " case 2:\n" " a->b();\n" " break;\n" " }\n" "}\n"); ASSERT_EQUALS("", errout.str()); // dereference in outer scope.. { const char code[] = "void foo(int x, const Token *tok) {\n" " if (x == 123) {\n" " while (tok) tok = tok->next();\n" " }\n" " tok->str();\n" "}\n"; check(code, false); ASSERT_EQUALS("", errout.str()); check(code, true); ASSERT_EQUALS("[test.cpp:5]: (error) Possible null pointer dereference: tok - otherwise it is redundant to check if tok is null at line 3\n", errout.str()); } check("int foo(const Token *tok)\n" "{\n" " while (tok){;}\n" "}\n", true); ASSERT_EQUALS("", errout.str()); check("int foo(const Token *tok)\n" "{\n" " while (tok){;}\n" " char a[2] = {0,0};\n" "}\n", true); ASSERT_EQUALS("", errout.str()); } void nullpointer1() { // ticket #1923 - no false positive when using else if check("void f(A *a)\n" "{\n" " if (a->x == 1)\n" " {\n" " a = a->next;\n" " }\n" " else if (a->x == 2) { }\n" " if (a) { }\n" "}\n"); ASSERT_EQUALS("", errout.str()); // ticket #2134 - sizeof doesn't dereference check("void f() {\n" " int c = 1;\n" " int *list = NULL;\n" " sizeof(*list);\n" " if (!list)\n" " ;\n" "}\n"); ASSERT_EQUALS("", errout.str()); // ticket #2245 - sizeof doesn't dereference check("void f(Bar *p) {\n" " if (!p) {\n" " int sz = sizeof(p->x);\n" " }\n" "}\n"); ASSERT_EQUALS("", errout.str()); } void nullpointer2() { // Null pointer dereference can only happen with pointers check("void foo()\n" "{\n" " Fred fred;\n" " while (fred);\n" " fred.hello();\n" "}\n"); ASSERT_EQUALS("", errout.str()); } // Dereferencing a struct and then checking if it is null // This is checked by this function: // CheckOther::nullPointerStructByDeRefAndChec void structDerefAndCheck() { // errors.. check("void foo(struct ABC *abc)\n" "{\n" " int a = abc->a;\n" " if (!abc)\n" " ;\n" "}\n"); ASSERT_EQUALS("[test.cpp:3]: (error) Possible null pointer dereference: abc - otherwise it is redundant to check if abc is null at line 4\n", errout.str()); check("void foo(struct ABC *abc) {\n" " bar(abc->a);\n" " if (!abc)\n" " ;\n" "}\n"); ASSERT_EQUALS("[test.cpp:2]: (error) Possible null pointer dereference: abc - otherwise it is redundant to check if abc is null at line 3\n", errout.str()); check("void foo(ABC *abc) {\n" " if (abc->a == 3) {\n" " return;\n" " }\n" " if (abc) {}\n" "}"); ASSERT_EQUALS("[test.cpp:2]: (error) Possible null pointer dereference: abc - otherwise it is redundant to check if abc is null at line 5\n", errout.str()); check("void f(ABC *abc) {\n" " if (abc->x == 0) {\n" " return;\n" " }\n" " if (!abc);\n" "}"); ASSERT_EQUALS("[test.cpp:2]: (error) Possible null pointer dereference: abc - otherwise it is redundant to check if abc is null at line 5\n", errout.str()); // TODO: False negative if member of member is dereferenced check("void foo(ABC *abc) {\n" " abc->next->a = 0;\n" " if (abc->next)\n" " ;\n" "}\n"); TODO_ASSERT_EQUALS("[test.cpp:2]: (error) Possible null pointer dereference: abc - otherwise it is redundant to check if abc is null at line 3\n", "", errout.str()); check("void foo(ABC *abc) {\n" " abc->a = 0;\n" " if (abc && abc->b == 0)\n" " ;\n" "}\n"); ASSERT_EQUALS("[test.cpp:2]: (error) Possible null pointer dereference: abc - otherwise it is redundant to check if abc is null at line 3\n", errout.str()); // ok dereferencing in a condition check("void foo(struct ABC *abc)\n" "{\n" " if (abc && abc->a);\n" " if (!abc)\n" " ;\n" "}\n"); ASSERT_EQUALS("", errout.str()); check("void f(struct ABC *abc) {\n" " int x = abc && a(abc->x);\n" " if (abc) { }\n" "}"); ASSERT_EQUALS("", errout.str()); // ok to use a linked list.. check("void foo(struct ABC *abc)\n" "{\n" " abc = abc->next;\n" " if (!abc)\n" " ;\n" "}\n"); ASSERT_EQUALS("", errout.str()); check("void f(struct ABC *abc) {\n" " abc = (ABC *)(abc->_next);\n" " if (abc) { }" "}\n"); ASSERT_EQUALS("", errout.str()); // reassign struct.. check("void foo(struct ABC *abc)\n" "{\n" " int a = abc->a;\n" " abc = abc->next;\n" " if (!abc)\n" " ;\n" "}\n"); ASSERT_EQUALS("", errout.str()); check("void foo(struct ABC *abc)\n" "{\n" " int a = abc->a;\n" " f(&abc);\n" " if (!abc)\n" " ;\n" "}\n"); ASSERT_EQUALS("", errout.str()); // goto.. check("void foo(struct ABC *abc)\n" "{\n" " int a;\n" " if (!abc)\n" " goto out;" " a = abc->a;\n" " return;\n" "out:\n" " if (!abc)\n" " ;\n" "}\n"); ASSERT_EQUALS("", errout.str()); // loops.. check("void foo(struct ABC *abc)\n" "{\n" " int a = abc->a;" " do\n" " {\n" " if (abc)\n" " abc = abc->next;\n" " --a;\n" " }\n" " while (a > 0);\n" "}\n"); ASSERT_EQUALS("", errout.str()); check("void f()\n" "{\n" " for (const Token *tok = _tokenizer->tokens(); tok; tok = tok->next())\n" " {\n" " while (tok && tok->str() != \"{\")\n" " tok = tok->next();\n" " if (!tok)\n" " return;\n" " }\n" "}\n"); ASSERT_EQUALS("", errout.str()); // dynamic_cast.. check("void foo(ABC *abc)\n" "{\n" " int a = abc->a;\n" " if (!dynamic_cast(abc))\n" " ;\n" "}\n"); ASSERT_EQUALS("", errout.str()); // #2641 - global pointer, function call check("ABC *abc;\n" "void f() {\n" " abc->a = 0;\n" " do_stuff();\n" " if (abc) { }\n" "}"); ASSERT_EQUALS("",errout.str()); check("Fred *fred;\n" "void f() {\n" " fred->foo();\n" " if (fred) { }\n" "}"); ASSERT_EQUALS("",errout.str()); // #2641 - local pointer, function call check("void f() {\n" " ABC *abc;\n" " abc->a = 0;\n" " do_stuff();\n" " if (abc) { }\n" "}"); ASSERT_EQUALS("[test.cpp:3]: (error) Possible null pointer dereference: abc - otherwise it is redundant to check if abc is null at line 5\n",errout.str()); // #2641 - local pointer, function call check("void f(ABC *abc) {\n" " abc->a = 0;\n" " do_stuff();\n" " if (abc) { }\n" "}"); ASSERT_EQUALS("[test.cpp:2]: (error) Possible null pointer dereference: abc - otherwise it is redundant to check if abc is null at line 4\n",errout.str()); // #2691 - switch/break check("void f(ABC *abc) {\n" " switch ( x ) {\n" " case 14:\n" " sprintf(buf, \"%d\", abc->a);\n" " break;\n" " case 15:\n" " if ( abc ) {}\n" " break;\n" " }\n" "}"); ASSERT_EQUALS("", errout.str()); // #3128 check("void f(ABC *abc) {\n" " x(!abc || y(abc->a));\n" " if (abc) {}\n" "}"); ASSERT_EQUALS("", errout.str()); // #3228 - calling function with null object { const char code[] = "void f(Fred *fred) {\n" " fred->x();\n" " if (fred) { }\n" "}"; check(code); ASSERT_EQUALS("", errout.str()); check(code, true); ASSERT_EQUALS("[test.cpp:2]: (error) Possible null pointer dereference: fred - otherwise it is redundant to check if fred is null at line 3\n", errout.str()); } // false positives when there are macros check("void f(struct FRED *fred) {\n" " fred->x = 0;\n" " $if(!fred){}\n" "}"); ASSERT_EQUALS("", errout.str()); } // Dereferencing a pointer and then checking if it is null void pointerDerefAndCheck() { // errors.. check("void foo(int *p)\n" "{\n" " *p = 0;\n" " if (!p)\n" " ;\n" "}\n"); ASSERT_EQUALS("[test.cpp:3]: (error) Possible null pointer dereference: p - otherwise it is redundant to check if p is null at line 4\n", errout.str()); check("void foo(int *p)\n" "{\n" " *p = 0;\n" " if (p) { }\n" "}\n"); ASSERT_EQUALS("[test.cpp:3]: (error) Possible null pointer dereference: p - otherwise it is redundant to check if p is null at line 4\n", errout.str()); check("void foo(int *p)\n" "{\n" " *p = 0;\n" " if (p || q) { }\n" "}\n"); ASSERT_EQUALS("[test.cpp:3]: (error) Possible null pointer dereference: p - otherwise it is redundant to check if p is null at line 4\n", errout.str()); check("void foo(int *p)\n" "{\n" " bar(*p);\n" " if (!p)\n" " ;\n" "}\n"); ASSERT_EQUALS("[test.cpp:3]: (error) Possible null pointer dereference: p - otherwise it is redundant to check if p is null at line 4\n", errout.str()); check("void foo(char *p)\n" "{\n" " strcpy(p, \"abc\");\n" " if (!p)\n" " ;\n" "}\n"); ASSERT_EQUALS("[test.cpp:3]: (error) Possible null pointer dereference: p - otherwise it is redundant to check if p is null at line 4\n", errout.str()); check("void foo(char *p)\n" "{\n" " if (*p == 0) { }\n" " if (!p) { }\n" "}\n"); TODO_ASSERT_EQUALS("[test.cpp:3]: (error) Possible null pointer dereference: p - otherwise it is redundant to check if p is null at line 4\n", "", errout.str()); // no error check("void foo()\n" "{\n" " int *p;\n" " f(&p);\n" " if (!p)\n" " ;\n" "}\n"); ASSERT_EQUALS("", errout.str()); check("void foo()\n" "{\n" " int **p = f();\n" " if (!p)\n" " ;\n" "}\n"); ASSERT_EQUALS("", errout.str()); check("void foo(int *p)\n" "{\n" " if (x)\n" " p = 0;\n" " else\n" " *p = 0;\n" " if (!p)\n" " ;\n" "}\n"); ASSERT_EQUALS("", errout.str()); check("void foo(int x)\n" "{\n" " int a = 2 * x;" " if (x == 0)\n" " ;\n" "}\n"); ASSERT_EQUALS("", errout.str()); check("void foo(int *p)\n" "{\n" " int var1 = p ? *p : 0;\n" " if (!p)\n" " ;\n" "}\n"); ASSERT_EQUALS("", errout.str()); check("void foo(int *p)\n" "{\n" " int var1 = x ? *p : 5;\n" " if (!p)\n" " ;\n" "}\n"); TODO_ASSERT_EQUALS("error", "", errout.str()); // Ticket #3125 check("void foo(ABC *p)\n" "{\n" " int var1 = p ? (p->a) : 0;\n" " if (!p)\n" " ;\n" "}\n"); ASSERT_EQUALS("", errout.str()); check("void foo(ABC *p)\n" "{\n" " int var1 = p ? (1 + p->a) : 0;\n" " if (!p)\n" " ;\n" "}\n"); ASSERT_EQUALS("", errout.str()); check("void foo(P *p)\n" "{\n" " while (p)\n" " if (p->check())\n" " break;\n" " else\n" " p = p->next();\n" "}\n"); ASSERT_EQUALS("", errout.str()); check("void f(Document *doc) {\n" " int x = doc && doc->x;\n" " if (!doc) {\n" " return;\n" " }\n" "}"); ASSERT_EQUALS("", errout.str()); // #3128 - false positive check("void f(int *p) {\n" " assert(!p || (*p<=6));\n" " if (p) { *p = 0; }\n" "}"); ASSERT_EQUALS("", errout.str()); check("void f(int *p) {\n" " assert(p && (*p<=6));\n" " if (p) { *p = 0; }\n" "}"); ASSERT_EQUALS("", errout.str()); check("void f(int *p) {\n" " *p = 12;\n" " assert(p && (*p<=6));\n" " if (p) { *p = 0; }\n" "}"); ASSERT_EQUALS("[test.cpp:2]: (error) Possible null pointer dereference: p - otherwise it is redundant to check if p is null at line 4\n", errout.str()); check("void foo(x *p)\n" "{\n" " p = p->next;\n" " if (!p)\n" " ;\n" "}\n"); ASSERT_EQUALS("", errout.str()); check("void foo(x *p)\n" "{\n" " p = bar(p->next);\n" " if (!p)\n" " ;\n" "}\n"); ASSERT_EQUALS("", errout.str()); check("void foo(x *p)\n" "{\n" " p = aa->bar(p->next);\n" " if (!p)\n" " ;\n" "}\n"); ASSERT_EQUALS("", errout.str()); check("void foo(struct ABC *abc)\n" "{\n" " abc = abc ? abc->next : 0;\n" " if (!abc)\n" " ;\n" "}\n"); ASSERT_EQUALS("", errout.str()); check("int f(Item *item) {\n" " x = item ? ab(item->x) : 0;\n" " if (item) { }\n" "}\n"); ASSERT_EQUALS("", errout.str()); check("int f(Item *item) {\n" " item->x = 0;\n" " a = b ? c : d;\n" " if (item) { }\n" "}\n"); ASSERT_EQUALS("[test.cpp:2]: (error) Possible null pointer dereference: item - otherwise it is redundant to check if item is null at line 4\n", errout.str()); check("BOOL GotoFlyAnchor()\n" // #2243 "{\n" " const SwFrm* pFrm = GetCurrFrm();\n" " do {\n" " pFrm = pFrm->GetUpper();\n" " } while( pFrm && !pFrm->IsFlyFrm() );\n" "\n" " if( !pFrm )\n" " return FALSE;\n" "}\n"); ASSERT_EQUALS("", errout.str()); // Ticket #2463 check("struct A \n" "{\n" " B* W;\n" "\n" " void f() {\n" " switch (InData) {\n" " case 2:\n" " if (!W) return;\n" " W->foo();\n" " break;\n" " case 3:\n" " f();\n" " if (!W) return;\n" " break;\n" " }\n" " }\n" "}\n"); ASSERT_EQUALS("", errout.str()); // #2525 - sizeof check("void f() {\n" " int *test = NULL;\n" " int c = sizeof(test[0]);\n" " if (!test)\n" " ;\n" "}\n"); ASSERT_EQUALS("", errout.str()); // #3023 - checked deref check("void f(struct ABC *abc) {\n" " WARN_ON(!abc || abc->x == 0);\n" " if (!abc) { }\n" "}"); ASSERT_EQUALS("", errout.str()); check("void f(struct ABC *abc) {\n" " WARN_ON(!abc || abc->x == 7);\n" " if (!abc) { }\n" "}"); ASSERT_EQUALS("", errout.str()); // false positives when there are macros check("void f(int *p) {\n" " *p = 0;\n" " $if(!p){}\n" "}"); ASSERT_EQUALS("", errout.str()); } void nullpointer5() { // errors.. check("void foo(A &a)\n" "{\n" " char c = a.c();\n" " if (!a)\n" " return;\n" "}\n"); ASSERT_EQUALS("", errout.str()); } // Execution paths.. void nullpointerExecutionPaths() { // errors.. check("static void foo()\n" "{\n" " Foo *p = 0;\n" " if (a == 1)\n" " p = new FooBar;\n" " else if (a == 2)\n" " p = new FooCar;\n" " p->abcd();\n" "}\n"); TODO_ASSERT_EQUALS("[test.cpp:8]: (error) Possible null pointer dereference: p\n", "", errout.str()); check("static void foo()\n" "{\n" " int *p = 0;\n" " int *q = p;\n" " q[0] = 0;\n" "}\n"); ASSERT_EQUALS("[test.cpp:5]: (error) Possible null pointer dereference: q\n", errout.str()); check("static void foo()\n" "{\n" " int *p = 0;\n" " int &r = *p;\n" "}\n"); ASSERT_EQUALS("[test.cpp:4]: (error) Null pointer dereference\n", errout.str()); check("static void foo(int x)\n" "{\n" " int *p = 0;\n" " int y = 5 + *p;\n" "}\n"); ASSERT_EQUALS("[test.cpp:4]: (error) Null pointer dereference\n", errout.str()); { const char code[] = "static void foo(int x)\n" "{\n" " Foo *abc = 0;\n" " abc->a();\n" "}\n"; // inconclusive=false => no error check(code,false); ASSERT_EQUALS("", errout.str()); // inconclusive=true => error check(code, true); ASSERT_EQUALS("[test.cpp:4]: (error) Possible null pointer dereference: abc\n", errout.str()); } check("static void foo()\n" "{\n" " int *p(0);\n" " std::cout << *p;" "}\n"); ASSERT_EQUALS("[test.cpp:4]: (error) Null pointer dereference\n", errout.str()); check("void f()\n" "{\n" " char *c = 0;\n" " {\n" " delete c;\n" " }\n" " c[0] = 0;\n" "}\n"); ASSERT_EQUALS("[test.cpp:7]: (error) Possible null pointer dereference: c\n", errout.str()); check("static void foo()\n" "{\n" " int *p = 0;\n" " if (3 > *p);\n" "}\n"); ASSERT_EQUALS("[test.cpp:4]: (error) Null pointer dereference\n", errout.str()); check("void f()\n" "{\n" " if (x) {\n" " char *c = 0;\n" " *c = 0;\n" " }\n" "}\n"); ASSERT_EQUALS("[test.cpp:5]: (error) Null pointer dereference\n", errout.str()); // no false positive.. check("static void foo()\n" "{\n" " Foo *p = 0;\n" " p = new Foo;\n" " p->abcd();\n" "}\n"); ASSERT_EQUALS("", errout.str()); check("static void foo()\n" "{\n" " Foo *p = 0;\n" " if (!p)\n" " return;\n" " p->abcd();\n" "}\n"); ASSERT_EQUALS("", errout.str()); check("static void foo()\n" "{\n" " int *p = 0;\n" " exit();\n" " *p = 0;\n" "}\n"); ASSERT_EQUALS("", errout.str()); check("static void foo(int a)\n" "{\n" " Foo *p = 0;\n" " if (a && p)\n" " p->do_something();\n" "}\n"); ASSERT_EQUALS("", errout.str()); check("void f() {\n" " Foo *p = 0;\n" " bool b = (p && (p->type() == 1));\n" "}\n"); ASSERT_EQUALS("", errout.str()); check("void foo()\n" "{\n" " int sz = sizeof((*(struct dummy *)0).x);\n" "}\n"); ASSERT_EQUALS("", errout.str()); check("void get_offset(long &offset)\n" "{\n" " mystruct * temp; temp = 0;\n" " offset = (long)(&(temp->z));\n" "}\n"); ASSERT_EQUALS("", errout.str()); // Ticket #1893 - try/catch inside else check("int *test(int *Z)\n" "{\n" " int *Q=NULL;\n" " if (Z) {\n" " Q = Z;\n" " }\n" " else {\n" " Z = new int;\n" " try {\n" " } catch(...) {\n" " }\n" " Q = Z;\n" " }\n" " *Q=1;\n" " return Q;\n" "}\n"); ASSERT_EQUALS("", errout.str()); check("int *test(int *Z)\n" "{\n" " int *Q=NULL;\n" " if (Z) {\n" " Q = Z;\n" " }\n" " else {\n" " try {\n" " } catch(...) {\n" " }\n" " }\n" " *Q=1;\n" " return Q;\n" "}\n"); ASSERT_EQUALS("[test.cpp:12]: (error) Possible null pointer dereference: Q\n", errout.str()); // Ticket #2052 (false positive for 'else continue;') check("void f() {\n" " for (int x = 0; x < 5; ++x) {" " int *p = 0;\n" " if (a(x)) p=b(x);\n" " else continue;\n" " *p = 0;\n" " }\n" "}"); ASSERT_EQUALS("", errout.str()); // function pointer.. check("void foo()\n" "{\n" " void (*f)();\n" " f = 0;\n" " f();\n" "}\n"); ASSERT_EQUALS("[test.cpp:5]: (error) Possible null pointer dereference: f\n", errout.str()); check("static void foo()\n" "{\n" " int *p = 0;\n" " int *p2 = 0;\n" " int r = *p;\n" " int r2 = *p2;\n" "}\n"); ASSERT_EQUALS("[test.cpp:5]: (error) Null pointer dereference\n" "[test.cpp:6]: (error) Null pointer dereference\n", errout.str()); // loops.. check("void f() {\n" " int *p = 0;\n" " for (int i = 0; i < 10; ++i) {\n" " int x = *p + 1;\n" " }\n" "}\n"); ASSERT_EQUALS("[test.cpp:4]: (error) Possible null pointer dereference: p\n", errout.str()); check("void f(int a) {\n" " const char *p = 0;\n" " if (a) {\n" " p = \"abcd\";\n" " }\n" " for (int i = 0; i < 3; i++) {\n" " if (a && (p[i] == '1'));\n" " }\n" "}\n"); ASSERT_EQUALS("", errout.str()); // ticket #2251: taking the address of member check("void f() {\n" " Fred *fred = 0;\n" " int x = &fred->x;\n" "}"); ASSERT_EQUALS("", errout.str()); // ticket #3220: calling member function check("void f() {\n" " Fred *fred = NULL;\n" " fred->do_something();\n" "}"); ASSERT_EQUALS("", errout.str()); } // Ticket #2350 void nullpointerExecutionPathsLoop() { // No false positive: check("void foo() {\n" " int n;\n" " int *argv32;\n" " if (x) {\n" " n = 0;\n" " argv32 = 0;\n" " }\n" "\n" " for (int i = 0; i < n; i++) {\n" " argv32[i] = 0;\n" " }\n" "}\n"); ASSERT_EQUALS("", errout.str()); // No false negative: check("void foo() {\n" " int n;\n" " int *argv32;\n" " if (x) {\n" " n = 10;\n" " argv32 = 0;\n" " }\n" "\n" " for (int i = 0; i < n; i++) {\n" " argv32[i] = 0;\n" " }\n" "}\n"); TODO_ASSERT_EQUALS("error", "", errout.str()); // #2231 - error if assignment in loop is not used check("void f() {\n" " char *p = 0;\n" "\n" " for (int x = 0; x < 3; ++x) {\n" " if (y[x] == 0) {\n" " p = malloc(10);\n" " break;\n" " }\n" " }\n" "\n" " *p = 0;\n" "}"); ASSERT_EQUALS("[test.cpp:11]: (error) Possible null pointer dereference: p\n", errout.str()); } void nullpointer7() { check("void foo()\n" "{\n" " wxLongLong x = 0;\n" " int y = x.GetValue();\n" "}\n"); ASSERT_EQUALS("", errout.str()); } void nullpointer8() { check("void foo()\n" "{\n" " const char * x = 0;\n" " strdup(x);\n" "}\n"); ASSERT_EQUALS("[test.cpp:4]: (error) Possible null pointer dereference: x\n", errout.str()); check("void foo()\n" "{\n" " char const * x = 0;\n" " strdup(x);\n" "}\n"); ASSERT_EQUALS("[test.cpp:4]: (error) Possible null pointer dereference: x\n", errout.str()); } void nullpointer9() { //#ticket 1778 check("void foo()\n" "{\n" " std::string * x = 0;\n" " *x = \"test\";\n" "}\n"); ASSERT_EQUALS("[test.cpp:4]: (error) Null pointer dereference\n", errout.str()); } void nullpointer10() { check("void foo()\n" "{\n" " struct my_type* p = 0;\n" " p->x = 0;\n" "}\n"); ASSERT_EQUALS("[test.cpp:4]: (error) Possible null pointer dereference: p\n", errout.str()); check("void foo()\n" "{\n" " struct my_type* p;\n" " p = 0; \n" " p->x = 0;\n" "}\n"); ASSERT_EQUALS("[test.cpp:5]: (error) Possible null pointer dereference: p\n", errout.str()); } void nullpointer11() { // ticket #2812 check("int foo()\n" "{\n" " my_type* p = 0;\n" " return p->x;\n" "}\n"); ASSERT_EQUALS("[test.cpp:4]: (error) Possible null pointer dereference: p\n", errout.str()); check("int foo()\n" "{\n" " struct my_type* p = 0;\n" " return p->x;\n" "}\n"); ASSERT_EQUALS("[test.cpp:4]: (error) Possible null pointer dereference: p\n", errout.str()); check("int foo()\n" "{\n" " my_type* p;\n" " p = 0; \n" " return p->x;\n" "}\n"); ASSERT_EQUALS("[test.cpp:5]: (error) Possible null pointer dereference: p\n", errout.str()); check("int foo()\n" "{\n" " struct my_type* p;\n" " p = 0; \n" " return p->x;\n" "}\n"); ASSERT_EQUALS("[test.cpp:5]: (error) Possible null pointer dereference: p\n", errout.str()); } void nullpointer12() { // ticket #2470 check("int foo()\n" "{\n" " int* i = nullptr;\n" " return *i;\n" "}\n", false, true); // Check as C++11 code ASSERT_EQUALS("[test.cpp:4]: (error) Null pointer dereference\n", errout.str()); check("int foo(int nullptr)\n" "{\n" " int* i = nullptr;\n" " return *i;\n" "}\n"); ASSERT_EQUALS("", errout.str()); } void nullpointer13() { // ticket #1780 check("void foo()\n" "{\n" " struct S\n" " {\n" " double *d;\n" " };\n" " S s;\n" " s.d=NULL;\n" " double *pd = s.d;\n" " *pd = 10;\n" "}\n"); ASSERT_EQUALS("[test.cpp:10]: (error) Null pointer dereference\n", errout.str()); } void nullpointer14() { check("void foo()\n" "{\n" " strcpy(bar, 0);\n" "}\n"); ASSERT_EQUALS("[test.cpp:3]: (error) Null pointer dereference\n", errout.str()); check("void foo()\n" "{\n" " memcmp(bar(xyz()), 0, 123);\n" "}\n"); ASSERT_EQUALS("[test.cpp:3]: (error) Null pointer dereference\n", errout.str()); check("void foo(const char *s)\n" "{\n" " char *p = malloc(100);\n" " frexp(1.0, p);\n" " char *q = 0;\n" " frexp(1.0, q);\n" "}\n"); ASSERT_EQUALS("[test.cpp:6]: (error) Possible null pointer dereference: q\n", errout.str()); } // Check if pointer is null and the dereference it void pointerCheckAndDeRef() { check("void foo(char *p) {\n" " if (!p) {\n" " }\n" " *p = 0;\n" "}\n"); ASSERT_EQUALS("[test.cpp:4]: (error) Possible null pointer dereference: p - otherwise it is redundant to check if p is null at line 2\n", errout.str()); check("void foo(char *p) {\n" " if (NULL == p) {\n" " }\n" " *p = 0;\n" "}\n"); ASSERT_EQUALS("[test.cpp:4]: (error) Possible null pointer dereference: p - otherwise it is redundant to check if p is null at line 2\n", errout.str()); check("void foo(char *p) {\n" " if (p == NULL) {\n" " }\n" " *p = 0;\n" "}\n"); ASSERT_EQUALS("[test.cpp:4]: (error) Possible null pointer dereference: p - otherwise it is redundant to check if p is null at line 2\n", errout.str()); check("void foo(char *p) {\n" " if (p == NULL) {\n" " }\n" " printf(\"%c\", *p);\n" "}\n"); ASSERT_EQUALS("[test.cpp:4]: (error) Possible null pointer dereference: p - otherwise it is redundant to check if p is null at line 2\n", errout.str()); check("void foo(char *p) {\n" " if (p && *p == 0) {\n" " }\n" " printf(\"%c\", *p);\n" "}\n"); ASSERT_EQUALS("[test.cpp:4]: (error) Possible null pointer dereference: p - otherwise it is redundant to check if p is null at line 2\n", errout.str()); check("void foo(char *p) {\n" " if (p && *p == 0) {\n" " } else { *p = 0; }\n" "}\n"); ASSERT_EQUALS("[test.cpp:3]: (error) Possible null pointer dereference: p - otherwise it is redundant to check if p is null at line 2\n", errout.str()); check("void foo(char *p) {\n" " if (p) {\n" " }\n" " strcpy(p, \"abc\");\n" "}\n"); ASSERT_EQUALS("[test.cpp:4]: (error) Possible null pointer dereference: p - otherwise it is redundant to check if p is null at line 2\n", errout.str()); check("void foo(char *p) {\n" " if (p) {\n" " }\n" " bar();\n" " strcpy(p, \"abc\");\n" "}\n"); ASSERT_EQUALS("[test.cpp:5]: (error) Possible null pointer dereference: p - otherwise it is redundant to check if p is null at line 2\n", errout.str()); check("void foo(abc *p) {\n" " if (!p) {\n" " }\n" " else if (!p->x) {\n" " }\n" "}\n"); ASSERT_EQUALS("", errout.str()); check("void foo(char *p) {\n" " if (!p) {\n" " abort();\n" " }\n" " *p = 0;\n" "}\n"); ASSERT_EQUALS("", errout.str()); check("void foo(char *p) {\n" " if (!p) {\n" " abort();\n" " }\n" " *p = 0;\n" "}\n", true); ASSERT_EQUALS("[test.cpp:5]: (error) Possible null pointer dereference: p - otherwise it is redundant to check if p is null at line 2\n", errout.str()); check("void foo(char *p) {\n" " if (!p) {\n" " (*bail)();\n" " }\n" " *p = 0;\n" "}\n"); ASSERT_EQUALS("", errout.str()); check("void foo(char *p) {\n" " if (!p) {\n" " throw x;\n" " }\n" " *p = 0;\n" "}\n"); ASSERT_EQUALS("", errout.str()); check("void foo(char *p) {\n" " if (!p) {\n" " ab.abort();\n" " }\n" " *p = 0;\n" "}\n"); ASSERT_EQUALS("", errout.str()); check("void foo(char *p) {\n" " if (!p) {\n" " switch (x) { }\n" " }\n" "}\n"); ASSERT_EQUALS("", errout.str()); check("void foo(char *p) {\n" " if (!p) {\n" " }\n" " return *x;\n" "}\n"); ASSERT_EQUALS("", errout.str()); check("int foo(int *p) {\n" " if (!p) {\n" " x = *p;\n" " return 5+*p;\n" " }\n" "}"); ASSERT_EQUALS("[test.cpp:3]: (error) Possible null pointer dereference: p - otherwise it is redundant to check if p is null at line 2\n" "[test.cpp:4]: (error) Possible null pointer dereference: p - otherwise it is redundant to check if p is null at line 2\n", errout.str()); // operator! check("void f() {\n" " A a;\n" " if (!a) {\n" " a.x();\n" " }\n" "}\n"); ASSERT_EQUALS("", errout.str()); // This is why this check can't be used on the simplified token list check("void f(Foo *foo) {\n" " if (!dynamic_cast(foo)) {\n" " *foo = 0;\n" " }\n" "}\n"); ASSERT_EQUALS("", errout.str()); // ticket: #2300 - calling unknown function that may initialize the pointer check("Fred *fred;\n" "void a() {\n" " if (!fred) {\n" " initfred();\n" " fred->x = 0;\n" " }\n" "}\n"); ASSERT_EQUALS("", errout.str()); // ticket #1219 check("void foo(char *p) {\n" " if (p) {\n" " return;\n" " }\n" " *p = 0;\n" "}\n"); ASSERT_EQUALS("[test.cpp:5]: (error) Possible null pointer dereference: p - otherwise it is redundant to check if p is null at line 2\n", errout.str()); // #2467 - unknown macro may terminate the application check("void f(Fred *fred) {\n" " if (fred == NULL) {\n" " MACRO;\n" " }\n" " fred->a();\n" "}"); ASSERT_EQUALS("", errout.str()); // #2493 - switch check("void f(Fred *fred) {\n" " if (fred == NULL) {\n" " x = 0;\n" " }\n" " switch (x) {\n" " case 1:\n" " fred->a();\n" " break;\n" " };\n" "}"); ASSERT_EQUALS("", errout.str()); // #2582 - segmentation fault check("if()"); // #2674 - different functions check("class Fred {\n" "public:\n" " Wilma *wilma;\n" " void a();\n" " void b();\n" "};\n" "\n" "void Fred::a() {\n" " if ( wilma ) { }\n" "}\n" "\n" "void Fred::b() {\n" " wilma->Reload();\n" "}\n"); ASSERT_EQUALS("", errout.str()); check("void test(int *i) {\n" " if(i == NULL) {\n" " int b = 1;\n" " } else {\n" " int b = *i;\n" " }\n" "}"); ASSERT_EQUALS("", errout.str()); // #2696 - false positives nr 1 check("void f()\n" "{\n" " struct foo *pFoo = NULL;\n" " size_t len;\n" "\n" " len = sizeof(*pFoo) - sizeof(pFoo->data);\n" "\n" " if (pFoo)\n" " bar();\n" "}"); ASSERT_EQUALS("", errout.str()); // #2696 - false positives nr 2 check("void f()\n" "{\n" " struct foo *pFoo = NULL;\n" " size_t len;\n" "\n" " while (pFoo)\n" " pFoo = pFoo->next;\n" "\n" " len = sizeof(pFoo->data);\n" "}"); ASSERT_EQUALS("", errout.str()); // #2696 - false positives nr 3 check("void f()\n" "{\n" " struct foo *pFoo = NULL;\n" " size_t len;\n" "\n" " while (pFoo)\n" " pFoo = pFoo->next;\n" "\n" " len = decltype(*pFoo);\n" "}"); ASSERT_EQUALS("", errout.str()); check("int foo(struct Fred *fred) {\n" " if (fred) { int a = 0; }\n" " return fred->a;\n" "}\n"); ASSERT_EQUALS("[test.cpp:3]: (error) Possible null pointer dereference: fred - otherwise it is redundant to check if fred is null at line 2\n", errout.str()); // #2789 - assign and check pointer check("void f() {\n" " char *p;\n" " if (!(p=x())) { }\n" " *p = 0;\n" "}\n"); ASSERT_EQUALS("[test.cpp:4]: (error) Possible null pointer dereference: p - otherwise it is redundant to check if p is null at line 3\n", errout.str()); // check, assign and use check("void f() {\n" " char *p;\n" " if (p == 0 && (p = malloc(10)) != 0) {\n" " *p = 0;\n" " }\n" "}"); ASSERT_EQUALS("", errout.str()); { const char code[] = "void f(Fred *fred) {\n" " if (fred == NULL) { }\n" " fred->x();\n" "}"; check(code); // non-inconclusive ASSERT_EQUALS("", errout.str()); check(code, true); // inconclusive ASSERT_EQUALS("[test.cpp:3]: (error) Possible null pointer dereference: fred - otherwise it is redundant to check if fred is null at line 2\n", errout.str()); } check("void f(char *s) {\n" // #3358 " if (s==0);\n" " strcpy(a, s?b:c);\n" "}\n"); ASSERT_EQUALS("", errout.str()); // sizeof check("void f(struct fred_t *fred) {\n" " if (!fred)\n" " int sz = sizeof fred->x;\n" "}"); ASSERT_EQUALS("", errout.str()); // check in macro check("void f(int *x) {\n" " $if (!x) {}\n" " *x = 0;\n" "}"); ASSERT_EQUALS("", errout.str()); } // Test CheckNullPointer::nullConstantDereference void nullConstantDereference() { // Ticket #2090 check("void foo() {\n" " char *p = 0;\n" " strcpy(p, \"abcd\");\n" "}\n"); ASSERT_EQUALS("[test.cpp:3]: (error) Null pointer dereference\n", errout.str()); // Ticket #2413 - it's ok to pass NULL to fflush check("void foo() {\n" " fflush(NULL);\n" "}\n"); ASSERT_EQUALS("", errout.str()); // Ticket #3126 - don't confuse member function with standard function check("void f() {\n" " image1.fseek(0, SEEK_SET);\n" "}"); ASSERT_EQUALS("", errout.str()); check("void f() {\n" " int* p = 0;\n" " return p[4];\n" "}"); ASSERT_EQUALS("[test.cpp:3]: (error) Null pointer dereference\n", errout.str()); } void gcc_statement_expression() { // Ticket #2621 check("void f(struct ABC *abc) {\n" " ({ if (abc) dbg(); })\n" "}"); ASSERT_EQUALS("", errout.str()); } void snprintf_with_zero_size() { // Ticket #2840 check("void f() {\n" " int bytes = snprintf(0, 0, \"%u\", 1);\n" "}"); ASSERT_EQUALS("", errout.str()); } void snprintf_with_non_zero_size() { // Ticket #2840 check("void f() {\n" " int bytes = snprintf(0, 10, \"%u\", 1);\n" "}"); ASSERT_EQUALS("[test.cpp:2]: (error) Null pointer dereference\n", errout.str()); } void printf_with_invalid_va_argument() { check("void f() {\n" " printf(\"%s\", 0);\n" "}"); ASSERT_EQUALS("[test.cpp:2]: (error) Null pointer dereference\n", errout.str()); check("void f(char* s) {\n" " printf(\"%s\", s);\n" "}"); ASSERT_EQUALS("", errout.str()); check("void f() {\n" " char* s = 0;\n" " printf(\"%s\", s);\n" "}"); ASSERT_EQUALS("[test.cpp:3]: (error) Possible null pointer dereference: s\n", errout.str()); check("void f() {\n" " char *s = 0;\n" " printf(\"%s\", s == 0 ? a : s);\n" "}\n"); ASSERT_EQUALS("", errout.str()); check("void f() {\n" " printf(\"%u%s\", 0, 0);\n" "}"); ASSERT_EQUALS("[test.cpp:2]: (error) Null pointer dereference\n", errout.str()); check("void f(char* s) {\n" " printf(\"%u%s\", 0, s);\n" "}"); ASSERT_EQUALS("", errout.str()); check("void f() {\n" " char* s = 0;\n" " printf(\"%u%s\", 123, s);\n" "}"); ASSERT_EQUALS("[test.cpp:3]: (error) Possible null pointer dereference: s\n", errout.str()); check("void f() {\n" " printf(\"%%%s%%\", 0);\n" "}"); ASSERT_EQUALS("[test.cpp:2]: (error) Null pointer dereference\n", errout.str()); check("void f(char* s) {\n" " printf(\"text: %s, %s\", s, 0);\n" "}"); ASSERT_EQUALS("[test.cpp:2]: (error) Null pointer dereference\n", errout.str()); check("void f() {\n" " char* s = \"blabla\";\n" " printf(\"%s\", s);\n" "}"); ASSERT_EQUALS("", errout.str()); check("void f(char* s) {\n" " printf(\"text: %m%s, %s\", s, 0);\n" "}"); ASSERT_EQUALS("[test.cpp:2]: (error) Null pointer dereference\n", errout.str()); check("void f(char* s) {\n" " printf(\"text: %*s, %s\", s, 0);\n" "}"); ASSERT_EQUALS("[test.cpp:2]: (error) Null pointer dereference\n", errout.str()); // Ticket #3364 check("void f() {\n" " printf(\"%-*.*s\", s, 0);\n" " sprintf(\"%*\", s);\n" "}"); ASSERT_EQUALS("", errout.str()); } void scanf_with_invalid_va_argument() { check("void f(char* s) {\n" " sscanf(s, \"%s\", 0);\n" "}"); ASSERT_EQUALS("[test.cpp:2]: (error) Null pointer dereference\n", errout.str()); check("void f() {\n" " scanf(\"%d\", 0);\n" "}"); ASSERT_EQUALS("[test.cpp:2]: (error) Null pointer dereference\n", errout.str()); check("void f(char* s) {\n" " printf(\"%s\", s);\n" "}"); ASSERT_EQUALS("", errout.str()); check("void f(char* foo) {\n" " char location[200];\n" " int width, height;\n" " sscanf(imgInfo, \"%s %d %d\", location, &width, &height);\n" "}"); ASSERT_EQUALS("", errout.str()); // ticket #3207 check("void f(char *dummy) {\n" " int iVal;\n" " sscanf(dummy, \"%d%c\", &iVal);\n" "}"); ASSERT_EQUALS("", errout.str()); // ticket #3211 check("void f(char *dummy) {\n" " int* iVal = 0;\n" " sscanf(dummy, \"%d\", iVal);\n" "}"); ASSERT_EQUALS("[test.cpp:3]: (error) Possible null pointer dereference: iVal\n", errout.str()); check("void f(char *dummy) {\n" " int* iVal;\n" " sscanf(dummy, \"%d\", foo(iVal));\n" "}"); ASSERT_EQUALS("", errout.str()); check("void f(char *dummy) {\n" " int* iVal = 0;\n" " sscanf(dummy, \"%d%d\", foo(iVal), iVal);\n" "}"); ASSERT_EQUALS("[test.cpp:3]: (error) Possible null pointer dereference: iVal\n", errout.str()); check("void f(char* dummy) {\n" " sscanf(dummy, \"%*d%u\", 0);\n" "}"); ASSERT_EQUALS("[test.cpp:2]: (error) Null pointer dereference\n", errout.str()); } void nullpointer_in_return() { check("int foo() {\n" " int* iVal = 0;\n" " if(g()) iVal = g();\n" " return iVal[0];\n" "}"); ASSERT_EQUALS("[test.cpp:4]: (error) Possible null pointer dereference: iVal\n", errout.str()); check("int foo(int* iVal) {\n" " return iVal[0];\n" "}"); ASSERT_EQUALS("", errout.str()); } void nullpointer_in_typeid() { // Should throw std::bad_typeid check("struct PolymorphicA { virtual ~A() {} };\n" "bool foo() {\n" " PolymorphicA* a = 0;\n" " return typeid(*a) == typeid(*a);\n" "}"); ASSERT_EQUALS("", errout.str()); check("struct NonPolymorphicA { ~A() {} };\n" "bool foo() {\n" " NonPolymorphicA* a = 0;\n" " return typeid(*a) == typeid(*a);\n" "}"); ASSERT_EQUALS("", errout.str()); check("bool foo() {\n" " char* c = 0;\n" " return typeid(*c) == typeid(*c);\n" "}"); ASSERT_EQUALS("", errout.str()); } void nullpointer_in_for_loop() { // Ticket #3278 check("void f(int* ptr, int cnt){\n" " if (!ptr)\n" " cnt = 0;\n" " for (int i = 0; i < cnt; ++i)\n" " *ptr++ = 0;\n" "}"); ASSERT_EQUALS("", errout.str()); } void nullpointerDelete() { check("void f() {\n" " K *k = getK();\n" " if (k)\n" " k->doStuff();\n" " delete k;\n" "}\n", true); ASSERT_EQUALS("", errout.str()); check("void f() {\n" " K *k = getK();\n" " if (k)\n" " k[0] = ptr;\n" " delete [] k;\n" " k = new K[10];\n" "}\n", true); ASSERT_EQUALS("", errout.str()); } void nullpointerExit() { check("void f() {\n" " K *k = getK();\n" " if (!k)\n" " exit(1);\n" " k->f();\n" "}\n", true); ASSERT_EQUALS("", errout.str()); } void nullpointerStdString() { check("void f(std::string s1) {\n" " void* p = 0;\n" " s1 = 0;\n" " std::string s2 = 0;\n" " std::string s3(0);\n" " foo(std::string(0));\n" " s1 = p;\n" " std::string s4 = p;\n" " std::string s5(p);\n" " foo(std::string(p));\n" "}", true); ASSERT_EQUALS("[test.cpp:3]: (error) Null pointer dereference\n" "[test.cpp:4]: (error) Null pointer dereference\n" "[test.cpp:5]: (error) Null pointer dereference\n" "[test.cpp:6]: (error) Null pointer dereference\n" "[test.cpp:7]: (error) Possible null pointer dereference: p\n" "[test.cpp:8]: (error) Possible null pointer dereference: p\n" "[test.cpp:9]: (error) Possible null pointer dereference: p\n" "[test.cpp:10]: (error) Possible null pointer dereference: p\n", errout.str()); check("void f(std::string s1, const std::string& s2, const std::string* s3) {\n" " void* p = 0;\n" " foo(s1 == p);\n" " foo(s2 == p);\n" " foo(s3 == p);\n" " foo(p == s1);\n" " foo(p == s2);\n" " foo(p == s3);\n" "}", true); ASSERT_EQUALS("[test.cpp:3]: (error) Null pointer dereference\n" "[test.cpp:4]: (error) Possible null pointer dereference: p\n" "[test.cpp:6]: (error) Possible null pointer dereference: p\n" "[test.cpp:7]: (error) Possible null pointer dereference: p\n", errout.str()); check("class Bar {\n" " std::string s;\n" " Bar() : s(0) {}\n" "};\n" "class Foo {\n" " std::string s;\n" " Foo();\n" "};\n" "Foo::Foo() : s(0) {}"); TODO_ASSERT_EQUALS("[test.cpp:3]: (error) Null pointer dereference\n" "[test.cpp:9]: (error) Null pointer dereference\n", "[test.cpp:3]: (error) Null pointer dereference\n", errout.str()); } void functioncall() { // #3443 - function calls // dereference pointer and then check if it's null { // function not seen check("void f(int *p) {\n" " *p = 0;\n" " foo(p);\n" " if (p) { }\n" "}"); ASSERT_EQUALS("", errout.str()); // function seen (taking pointer parameter) check("void foo(int *p) { }\n" "\n" "void f(int *p) {\n" " *p = 0;\n" " foo(p);\n" " if (p) { }\n" "}"); ASSERT_EQUALS("[test.cpp:4]: (error) Possible null pointer dereference: p - otherwise it is redundant to check if p is null at line 6\n", errout.str()); // function implementation not seen check("void foo(int *p);\n" "\n" "void f(int *p) {\n" " *p = 0;\n" " foo(p);\n" " if (p) { }\n" "}"); TODO_ASSERT_EQUALS("[test.cpp:4]: (error) Possible null pointer dereference: p - otherwise it is redundant to check if p is null at line 6\n", "", errout.str()); // inconclusive check("void f(int *p) {\n" " *p = 0;\n" " foo(p);\n" " if (p) { }\n" "}", true); ASSERT_EQUALS("[test.cpp:2]: (error) Possible null pointer dereference: p - otherwise it is redundant to check if p is null at line 4\n", errout.str()); } // dereference struct pointer and then check if it's null { // function not seen check("void f(struct ABC *abc) {\n" " abc->a = 0;\n" " foo(abc);\n" " if (abc) { }\n" "}"); ASSERT_EQUALS("", errout.str()); // function seen (taking pointer parameter) check("void foo(struct ABC *abc) { }\n" "\n" "void f(struct ABC *abc) {\n" " abc->a = 0;\n" " foo(abc);\n" " if (abc) { }\n" "}"); ASSERT_EQUALS("[test.cpp:4]: (error) Possible null pointer dereference: abc - otherwise it is redundant to check if abc is null at line 6\n", errout.str()); // function implementation not seen check("void foo(struct ABC *abc);\n" "\n" "void f(struct ABC *abc) {\n" " abc->a = 0;\n" " foo(abc);\n" " if (abc) { }\n" "}"); TODO_ASSERT_EQUALS("[test.cpp:4]: (error) Possible null pointer dereference: abc - otherwise it is redundant to check if abc is null at line 6\n", "", errout.str()); // inconclusive check("void f(struct ABC *abc) {\n" " abc->a = 0;\n" " foo(abc);\n" " if (abc) { }\n" "}", true); ASSERT_EQUALS("[test.cpp:2]: (error) Possible null pointer dereference: abc - otherwise it is redundant to check if abc is null at line 4\n", errout.str()); } } }; REGISTER_TEST(TestNullPointer)