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/*
* 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 <http://www.gnu.org/licenses/>.
*/
#include "tokenize.h"
#include "checknullpointer.h"
#include "testsuite.h"
#include <sstream>
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(nullpointer15); // #3560 (fp: return p ? f(*p) : f(0))
TEST_CASE(nullpointer16); // #3591
TEST_CASE(nullpointer17); // #3567
TEST_CASE(nullpointer18); // #1927
TEST_CASE(nullpointer19); // #3811
TEST_CASE(nullpointer20); // #3807 (fp: return p ? (p->x() || p->y()) : z)
TEST_CASE(nullpointer_castToVoid); // #3771
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(nullpointerStdStream);
TEST_CASE(functioncall);
TEST_CASE(crash1);
}
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);
if (!tokenizer.tokenize(istr, "test.cpp"))
return;
// 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] -> [test.cpp:3]: (error) Possible null pointer dereference: tok - otherwise it is redundant to check it against null.\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] -> [test.cpp:3]: (error, inconclusive) Possible null pointer dereference: tok - otherwise it is redundant to check it against null.\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] -> [test.cpp:5]: (error) Possible null pointer dereference: tok - otherwise it is redundant to check it against null.\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] -> [test.cpp:3]: (error, inconclusive) Possible null pointer dereference: tok - otherwise it is redundant to check it against null.\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"
"}", true);
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"
"}", true);
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"
"}", true);
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] -> [test.cpp:4]: (error) Possible null pointer dereference: abc - otherwise it is redundant to check it against null.\n", errout.str());
check("void foo(struct ABC *abc) {\n"
" bar(abc->a);\n"
" if (!abc)\n"
" ;\n"
"}\n");
ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:3]: (error) Possible null pointer dereference: abc - otherwise it is redundant to check it against null.\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] -> [test.cpp:5]: (error) Possible null pointer dereference: abc - otherwise it is redundant to check it against null.\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] -> [test.cpp:5]: (error) Possible null pointer dereference: abc - otherwise it is redundant to check it against null.\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] -> [test.cpp:3]: (error) Possible null pointer dereference: abc - otherwise it is redundant to check it against null.\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] -> [test.cpp:3]: (error) Possible null pointer dereference: abc - otherwise it is redundant to check it against null.\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"
"}", true);
ASSERT_EQUALS("", errout.str());
check("void f(struct ABC *abc) {\n"
" abc = (ABC *)(abc->_next);\n"
" if (abc) { }"
"}", true);
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"
"}", true);
ASSERT_EQUALS("", errout.str());
check("void foo(struct ABC *abc)\n"
"{\n"
" int a = abc->a;\n"
" f(&abc);\n"
" if (!abc)\n"
" ;\n"
"}", true);
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<DEF *>(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] -> [test.cpp:5]: (error) Possible null pointer dereference: abc - otherwise it is redundant to check it against null.\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] -> [test.cpp:4]: (error) Possible null pointer dereference: abc - otherwise it is redundant to check it against null.\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] -> [test.cpp:3]: (error, inconclusive) Possible null pointer dereference: fred - otherwise it is redundant to check it against null.\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] -> [test.cpp:4]: (error) Possible null pointer dereference: p - otherwise it is redundant to check it against null.\n", errout.str());
check("void foo(int *p)\n"
"{\n"
" *p = 0;\n"
" if (p) { }\n"
"}\n");
ASSERT_EQUALS("[test.cpp:3] -> [test.cpp:4]: (error) Possible null pointer dereference: p - otherwise it is redundant to check it against null.\n", errout.str());
check("void foo(int *p)\n"
"{\n"
" *p = 0;\n"
" if (p || q) { }\n"
"}\n");
ASSERT_EQUALS("[test.cpp:3] -> [test.cpp:4]: (error) Possible null pointer dereference: p - otherwise it is redundant to check it against null.\n", errout.str());
check("void foo(int *p)\n"
"{\n"
" bar(*p);\n"
" if (!p)\n"
" ;\n"
"}\n");
ASSERT_EQUALS("[test.cpp:3] -> [test.cpp:4]: (error) Possible null pointer dereference: p - otherwise it is redundant to check it against null.\n", errout.str());
check("void foo(char *p)\n"
"{\n"
" strcpy(p, \"abc\");\n"
" if (!p)\n"
" ;\n"
"}\n");
ASSERT_EQUALS("[test.cpp:3] -> [test.cpp:4]: (error) Possible null pointer dereference: p - otherwise it is redundant to check it against null.\n", errout.str());
check("void foo(char *p)\n"
"{\n"
" if (*p == 0) { }\n"
" if (!p) { }\n"
"}\n");
TODO_ASSERT_EQUALS("[test.cpp:3] -> [test.cpp:4]: (error) Possible null pointer dereference: p - otherwise it is redundant to check it against null.\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"
"}", true);
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"
"}", true);
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] -> [test.cpp:4]: (error) Possible null pointer dereference: p - otherwise it is redundant to check it against null.\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(x *p)\n"
"{\n"
" p = *p2 = 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] -> [test.cpp:4]: (error) Possible null pointer dereference: item - otherwise it is redundant to check it against null.\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"
"}", true);
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());
check("void f() {\n" // #3914 - false positive
" int *p;\n"
" ((p=ret()) && (x=*p));\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<int> *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"
"}", true);
ASSERT_EQUALS("", errout.str());
// ticket #2251: taking the address of member
check("void f() {\n"
" Fred *fred = 0;\n"
" int x = &fred->x;\n"
"}", true);
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 #3570 - parsing of conditions
{
check("void f() {\n"
" int *p = NULL;\n"
" if (x)\n"
" p = q;\n"
" if (p && *p) { }\n"
"}", true);
ASSERT_EQUALS("", errout.str());
check("void f() {\n"
" int *p = NULL;\n"
" if (x)\n"
" p = q;\n"
" if (!p || *p) { }\n"
"}", true);
ASSERT_EQUALS("", errout.str());
check("void f() {\n"
" int *p = NULL;\n"
" if (x)\n"
" p = q;\n"
" if (p || *p) { }\n"
"}");
TODO_ASSERT_EQUALS("error", "", 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"
"}", true);
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"
"}", true);
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());
}
void nullpointer15() { // #3560
check("void f() {\n"
" char *p = 0;\n"
" if (x) p = \"abcd\";\n"
" return p ? f(*p) : f(0);\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void nullpointer16() { // #3591
check("void foo() {\n"
" int *p = 0;\n"
" bar(&p);\n"
" *p = 0;\n"
"}", true);
ASSERT_EQUALS("", errout.str());
}
void nullpointer17() { // #3567
check("int foo() {\n"
" int *p = 0;\n"
" return (!p || *p);\n"
"}", true);
ASSERT_EQUALS("", errout.str());
check("int foo() {\n"
" int *p = 0;\n"
" return p && *p;\n"
"}", true);
ASSERT_EQUALS("", errout.str());
}
void nullpointer18() { // #1927
check("void f ()\n"
"{\n"
" int i=0;\n"
" char *str=NULL;\n"
" while (str[i])\n"
" {\n"
" i++;\n"
" };\n"
"}\n"
);
ASSERT_EQUALS("[test.cpp:5]: (error) Null pointer dereference\n", errout.str());
}
void nullpointer19() { // #3811
check("int foo() {\n"
" perror(0);\n"
"}", true);
ASSERT_EQUALS("", errout.str());
}
void nullpointer20() { // #3807
check("void f(int x) {\n"
" struct xy *p = 0;\n"
" if (x) p = q;\n"
" if (p ? p->x || p->y : 0) { }\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void f(int x) {\n" // false negative
" struct xy *p = 0;\n"
" if (x) p = q;\n"
" if (y ? p->x : p->y) { }\n"
"}");
TODO_ASSERT_EQUALS("error", "", errout.str());
}
void nullpointer_castToVoid() { // #3771
check("void f () {\n"
" int *buf = NULL;\n"
" (void)buf;\n"
"}", true);
ASSERT_EQUALS("", 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] -> [test.cpp:2]: (error) Possible null pointer dereference: p - otherwise it is redundant to check it against null.\n", errout.str());
check("void foo(char *p) {\n"
" if (NULL == p) {\n"
" }\n"
" *p = 0;\n"
"}\n");
ASSERT_EQUALS("[test.cpp:4] -> [test.cpp:2]: (error) Possible null pointer dereference: p - otherwise it is redundant to check it against null.\n", errout.str());
check("void foo(char *p) {\n"
" if (p == NULL) {\n"
" }\n"
" *p = 0;\n"
"}\n");
ASSERT_EQUALS("[test.cpp:4] -> [test.cpp:2]: (error) Possible null pointer dereference: p - otherwise it is redundant to check it against null.\n", errout.str());
check("void foo(char *p) {\n"
" if (p == NULL) {\n"
" }\n"
" printf(\"%c\", *p);\n"
"}\n");
ASSERT_EQUALS("[test.cpp:4] -> [test.cpp:2]: (error) Possible null pointer dereference: p - otherwise it is redundant to check it against null.\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] -> [test.cpp:2]: (error) Possible null pointer dereference: p - otherwise it is redundant to check it against null.\n", errout.str());
check("void foo(char *p) {\n"
" if (p && *p == 0) {\n"
" } else { *p = 0; }\n"
"}\n");
ASSERT_EQUALS("[test.cpp:3] -> [test.cpp:2]: (error) Possible null pointer dereference: p - otherwise it is redundant to check it against null.\n", errout.str());
check("void foo(char *p) {\n"
" if (p) {\n"
" }\n"
" strcpy(p, \"abc\");\n"
"}\n");
ASSERT_EQUALS("[test.cpp:4] -> [test.cpp:2]: (error) Possible null pointer dereference: p - otherwise it is redundant to check it against null.\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] -> [test.cpp:2]: (error) Possible null pointer dereference: p - otherwise it is redundant to check it against null.\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] -> [test.cpp:2]: (error, inconclusive) Possible null pointer dereference: p - otherwise it is redundant to check it against null.\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"
"}", true);
ASSERT_EQUALS("", errout.str());
check("void foo(char *p) {\n"
" if (!p) {\n"
" }\n"
" return *x;\n"
"}", true);
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] -> [test.cpp:2]: (error) Possible null pointer dereference: p - otherwise it is redundant to check it against null.\n"
"[test.cpp:4] -> [test.cpp:2]: (error) Possible null pointer dereference: p - otherwise it is redundant to check it against null.\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<bar *>(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] -> [test.cpp:2]: (error) Possible null pointer dereference: p - otherwise it is redundant to check it against null.\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"
"}", true);
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"
"}", true);
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"
"}", true);
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"
"}", true);
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"
"}", true);
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] -> [test.cpp:2]: (error) Possible null pointer dereference: fred - otherwise it is redundant to check it against null.\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] -> [test.cpp:3]: (error) Possible null pointer dereference: p - otherwise it is redundant to check it against null.\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());
// check, assign and use
check("void f() {\n"
" char *p;\n"
" if (p == 0 && (p = malloc(10)) != a && (*p = a)) {\n"
" *p = 0;\n"
" }\n"
"}");
ASSERT_EQUALS("", errout.str());
// check, and use
check("void f() {\n"
" char *p;\n"
" if (p == 0 && (*p = 0)) {\n"
" return;\n"
" }\n"
"}");
ASSERT_EQUALS("[test.cpp:3] -> [test.cpp:3]: (error) Possible null pointer dereference: p - otherwise it is redundant to check it against null.\n", errout.str());
// check, and use
check("void f() {\n"
" struct foo *p;\n"
" if (p == 0 && p->x == 10) {\n"
" return;\n"
" }\n"
"}");
ASSERT_EQUALS("[test.cpp:3] -> [test.cpp:3]: (error) Possible null pointer dereference: p - otherwise it is redundant to check it against null.\n", errout.str());
// check, and use
check("void f() {\n"
" struct foo *p;\n"
" if (p == 0 || p->x == 10) {\n"
" return;\n"
" }\n"
"}");
ASSERT_EQUALS("", errout.str());
// check, and use
check("void f() {\n"
" char *p;\n"
" if ((p = malloc(10)) == NULL && (*p = a)) {\n"
" return;\n"
" }\n"
"}");
ASSERT_EQUALS("[test.cpp:3] -> [test.cpp:3]: (error) Possible null pointer dereference: p - otherwise it is redundant to check it against null.\n", errout.str());
// check, and use
check("void f(struct X *p, int x) {\n"
" if (!p && x==1 || p && p->x==0) {\n"
" return;\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] -> [test.cpp:2]: (error, inconclusive) Possible null pointer dereference: fred - otherwise it is redundant to check it against null.\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"
"}", true);
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 #1171
check("void foo(void* bar) {\n"
" if(strcmp(0, bar) == 0)\n"
" func();\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (error) Null pointer dereference\n", errout.str());
// Ticket #2413 - it's ok to pass NULL to fflush
check("void foo() {\n"
" fflush(NULL);\n"
"}", true);
ASSERT_EQUALS("", errout.str());
// Ticket #3126 - don't confuse member function with standard function
check("void f() {\n"
" image1.fseek(0, SEEK_SET);\n"
"}", true);
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"
"}", true);
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* 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"
"}", true);
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"
"}", true);
ASSERT_EQUALS("", errout.str());
check("struct NonPolymorphicA { ~A() {} };\n"
"bool foo() {\n"
" NonPolymorphicA* a = 0;\n"
" return typeid(*a) == typeid(*a);\n"
"}", true);
ASSERT_EQUALS("", errout.str());
check("bool foo() {\n"
" char* c = 0;\n"
" return typeid(*c) == typeid(*c);\n"
"}", true);
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) {}");
ASSERT_EQUALS("[test.cpp:3]: (error) Null pointer dereference\n"
"[test.cpp:9]: (error) Null pointer dereference\n", errout.str());
check("void f() {\n"
" std::string s = 0 == x ? \"a\" : \"b\";\n"
"}", true);
ASSERT_EQUALS("", errout.str());
}
void nullpointerStdStream() {
check("void f(std::ifstream& is) {\n"
" char* p = 0;\n"
" is >> p;\n"
"}");
ASSERT_EQUALS("[test.cpp:3]: (error) Possible null pointer dereference: p\n", errout.str());
check("void f(const std::ostringstream& oss, char* q) {\n"
" char const* p = 0;\n" // Simplification makes detection of bug difficult
" oss << p;\n"
" oss << foo << p;\n"
" if(q == 0)\n"
" oss << foo << q;\n"
"}");
TODO_ASSERT_EQUALS("[test.cpp:3]: (error) Possible null pointer dereference: p\n"
"[test.cpp:4]: (error) Possible null pointer dereference: p\n"
"[test.cpp:6] -> [test.cpp:5]: (error) Possible null pointer dereference: q - otherwise it is redundant to check it against null.\n",
"[test.cpp:6] -> [test.cpp:5]: (error) Possible null pointer dereference: q - otherwise it is redundant to check it against null.\n", errout.str());
check("void f(const char* p) {\n"
" if(p == 0) {\n"
" std::cout << p;\n"
" std::cerr << p;\n"
" std::cin >> p;\n"
" std::cout << abc << p;\n"
" }\n"
"}");
ASSERT_EQUALS("[test.cpp:3] -> [test.cpp:2]: (error) Possible null pointer dereference: p - otherwise it is redundant to check it against null.\n"
"[test.cpp:4] -> [test.cpp:2]: (error) Possible null pointer dereference: p - otherwise it is redundant to check it against null.\n"
"[test.cpp:5] -> [test.cpp:2]: (error) Possible null pointer dereference: p - otherwise it is redundant to check it against null.\n"
"[test.cpp:6] -> [test.cpp:2]: (error) Possible null pointer dereference: p - otherwise it is redundant to check it against null.\n", errout.str());
check("void f() {\n"
" void* p1 = 0;\n"
" std::cout << p1;\n" // No char*
" char* p2 = 0;\n"
" std::cin >> (int)p;\n" // result casted
" std::cout << (int)p;\n"
"}", true);
ASSERT_EQUALS("", errout.str());
check("void f(const std::string& str) {\n"
" long long ret = 0;\n"
" std::istringstream istr(str);\n"
" istr >> std::hex >> ret;\n" // Read integer
" return ret;\n"
"}", true);
ASSERT_EQUALS("", 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] -> [test.cpp:6]: (error) Possible null pointer dereference: p - otherwise it is redundant to check it against null.\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] -> [test.cpp:6]: (error) Possible null pointer dereference: p - otherwise it is redundant to check it against null.\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] -> [test.cpp:4]: (error, inconclusive) Possible null pointer dereference: p - otherwise it is redundant to check it against null.\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] -> [test.cpp:6]: (error) Possible null pointer dereference: abc - otherwise it is redundant to check it against null.\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] -> [test.cpp:6]: (error) Possible null pointer dereference: abc - otherwise it is redundant to check it against null.\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] -> [test.cpp:4]: (error, inconclusive) Possible null pointer dereference: abc - otherwise it is redundant to check it against null.\n", errout.str());
}
}
void crash1() {
check("int f() {\n"
" return if\n"
"}");
}
};
REGISTER_TEST(TestNullPointer)
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