cppcheck/test/testother.cpp

883 lines
28 KiB
C++

/*
* Cppcheck - A tool for static C/C++ code analysis
* Copyright (C) 2007-2009 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 "../src/tokenize.h"
#include "../src/checkother.h"
#include "testsuite.h"
#include <sstream>
extern std::ostringstream errout;
class TestOther : public TestFixture
{
public:
TestOther() : TestFixture("TestOther")
{ }
private:
void run()
{
TEST_CASE(zeroDiv1);
TEST_CASE(zeroDiv2);
TEST_CASE(zeroDiv3);
TEST_CASE(zeroDiv4);
TEST_CASE(delete1);
TEST_CASE(delete2);
TEST_CASE(unreachable1);
TEST_CASE(sprintf1); // Dangerous usage of sprintf
TEST_CASE(sprintf2);
TEST_CASE(sprintf3);
TEST_CASE(sprintf4); // struct member
TEST_CASE(strPlusChar1); // "/usr" + '/'
TEST_CASE(strPlusChar2); // "/usr" + ch
TEST_CASE(strPlusChar3); // ok: path + "/sub" + '/'
TEST_CASE(varScope1);
TEST_CASE(varScope2);
TEST_CASE(varScope3);
TEST_CASE(varScope4);
TEST_CASE(varScope5);
TEST_CASE(varScope6);
TEST_CASE(nullpointer1);
TEST_CASE(nullpointer2);
TEST_CASE(nullpointer3); // dereferencing struct and then checking if it's null
TEST_CASE(nullpointer4);
TEST_CASE(oldStylePointerCast);
TEST_CASE(postIncrementDecrementStl);
TEST_CASE(postIncrementDecrementClass);
}
void check(const char code[])
{
// Tokenize..
Tokenizer tokenizer;
std::istringstream istr(code);
tokenizer.tokenize(istr, "test.cpp");
// Simplify token list..
tokenizer.simplifyTokenList();
// Clear the error buffer..
errout.str("");
// Check for redundant code..
Settings settings;
CheckOther checkOther(&tokenizer, &settings, this);
checkOther.warningRedundantCode();
checkOther.checkZeroDivision();
}
void zeroDiv1()
{
check("void foo()\n"
"{\n"
" int a = 0;\n"
" double b = 1.;\n"
" cout<<b/a;\n"
"}");
ASSERT_EQUALS("[test.cpp:5]: (error) Division by zero\n", errout.str());
}
void zeroDiv2()
{
check("void foo()\n"
"{\n"
" int sum = 0;\n"
" int n = 100;\n"
" for(int i = 0; i < n; i ++)\n"
" {\n"
" sum += i; \n"
" }\n"
" cout<<b/sum;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("void foo()\n"
"{\n"
" int a = 0 ? (2/0) : 0;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
}
void zeroDiv3()
{
check("void f()\n"
"{\n"
" div_t divresult = div (1,0);\n"
"}\n");
ASSERT_EQUALS("[test.cpp:3]: (error) Division by zero\n", errout.str());
}
void zeroDiv4()
{
check("void f()\n"
"{\n"
" long a = b / 0x6;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("void f()\n"
"{\n"
" long a = b / 0x0;\n"
"}\n");
ASSERT_EQUALS("[test.cpp:3]: (error) Division by zero\n", errout.str());
check("void f()\n"
"{\n"
" long a = b / 0L;\n"
"}\n");
ASSERT_EQUALS("[test.cpp:3]: (error) Division by zero\n", errout.str());
check("void f()\n"
"{\n"
" long a = b / 0ul;\n"
"}\n");
ASSERT_EQUALS("[test.cpp:3]: (error) Division by zero\n", errout.str());
check("void f()\n"
"{\n"
" div_t divresult = div (1,0L);\n"
"}\n");
ASSERT_EQUALS("[test.cpp:3]: (error) Division by zero\n", errout.str());
check("void f()\n"
"{\n"
" div_t divresult = div (1,0x5);\n"
"}\n");
ASSERT_EQUALS("", errout.str());
// Don't warn about floating points (gcc doesn't warn either)
// and floating points are handled differently than integers.
check("void f()\n"
"{\n"
" long a = b / 0.0;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("void f()\n"
"{\n"
" long a = b / 0.5;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
// Don't warn about 0.0
check("void f()\n"
"{\n"
" div_t divresult = div (1,0.0);\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("void f()\n"
"{\n"
" div_t divresult = div (1,0.5);\n"
"}\n");
ASSERT_EQUALS("", errout.str());
}
void delete1()
{
check("void foo()\n"
"{\n"
" if (p)\n"
" {\n"
" delete p;\n"
" p = 0;\n"
" }\n"
"}\n");
ASSERT_EQUALS("", errout.str());
}
void delete2()
{
check("void foo()\n"
"{\n"
" if (p)\n"
" {\n"
" delete p;\n"
" }\n"
"}\n");
ASSERT_EQUALS("[test.cpp:3]: (style) Redundant condition. It is safe to deallocate a NULL pointer\n", errout.str());
check("void foo()\n"
"{\n"
" if (p)\n"
" delete p;\n"
"}\n");
ASSERT_EQUALS("[test.cpp:3]: (style) Redundant condition. It is safe to deallocate a NULL pointer\n", errout.str());
check("void foo()\n"
"{\n"
" if (p != NULL)\n"
" delete p;\n"
"}\n");
ASSERT_EQUALS("[test.cpp:3]: (style) Redundant condition. It is safe to deallocate a NULL pointer\n", errout.str());
check("void foo()\n"
"{\n"
" if (p)\n"
" delete [] p;\n"
"}\n");
ASSERT_EQUALS("[test.cpp:3]: (style) Redundant condition. It is safe to deallocate a NULL pointer\n", errout.str());
check("void foo()\n"
"{\n"
" if (0 != this->p)\n"
" delete this->p;\n"
"}\n");
ASSERT_EQUALS("[test.cpp:3]: (style) Redundant condition. It is safe to deallocate a NULL pointer\n", errout.str());
check("void Foo::deleteInstance()\n"
"{\n"
" if (Foo::instance != NULL)\n"
" delete Foo::instance;\n"
"}\n");
ASSERT_EQUALS("[test.cpp:3]: (style) Redundant condition. It is safe to deallocate a NULL pointer\n", errout.str());
}
void unreachable1()
{
check("void foo()\n"
"{\n"
" switch (p)\n"
" {\n"
" default:\n"
" return 0;\n"
" break;\n"
" }\n"
"}\n");
ASSERT_EQUALS("", errout.str());
}
void sprintfUsage(const char code[])
{
// Tokenize..
Tokenizer tokenizer;
std::istringstream istr(code);
tokenizer.tokenize(istr, "test.cpp");
tokenizer.setVarId();
//tokenizer.tokens()->printOut( "tokens" );
// Clear the error buffer..
errout.str("");
// Check for redundant code..
Settings settings;
CheckOther checkOther(&tokenizer, &settings, this);
checkOther.invalidFunctionUsage();
}
void sprintf1()
{
sprintfUsage("void foo()\n"
"{\n"
" char buf[100];\n"
" sprintf(buf,\"%s\",buf);\n"
"}\n");
ASSERT_EQUALS("[test.cpp:4]: (error) Overlapping data buffer buf\n", errout.str());
}
void sprintf2()
{
sprintfUsage("void foo()\n"
"{\n"
" char buf[100];\n"
" sprintf(buf,\"%i\",sizeof(buf));\n"
"}\n");
ASSERT_EQUALS("", errout.str());
}
void sprintf3()
{
sprintfUsage("void foo()\n"
"{\n"
" char buf[100];\n"
" sprintf(buf,\"%i\",sizeof(buf));\n"
" if (buf[0]);\n"
"}\n");
ASSERT_EQUALS("", errout.str());
}
void sprintf4()
{
sprintfUsage("struct A\n"
"{\n"
" char filename[128];\n"
"};\n"
"\n"
"void foo()\n"
"{\n"
" const char* filename = \"hello\";\n"
" struct A a;\n"
" snprintf(a.filename, 128, \"%s\", filename);\n"
"}\n");
ASSERT_EQUALS("", errout.str());
}
void strPlusChar(const char code[])
{
// Tokenize..
Tokenizer tokenizer;
std::istringstream istr(code);
tokenizer.tokenize(istr, "test.cpp");
tokenizer.setVarId();
// Clear the error buffer..
errout.str("");
// Check for redundant code..
Settings settings;
CheckOther checkOther(&tokenizer, &settings, this);
checkOther.strPlusChar();
}
void strPlusChar1()
{
// Strange looking pointer arithmetic..
strPlusChar("void foo()\n"
"{\n"
" const char *p = \"/usr\" + '/';\n"
"}\n");
ASSERT_EQUALS("[test.cpp:3]: (error) Unusual pointer arithmetic\n", errout.str());
}
void strPlusChar2()
{
// Strange looking pointer arithmetic..
strPlusChar("void foo()\n"
"{\n"
" char ch = '/';\n"
" const char *p = \"/usr\" + ch;\n"
"}\n");
ASSERT_EQUALS("[test.cpp:4]: (error) Unusual pointer arithmetic\n", errout.str());
}
void strPlusChar3()
{
// Strange looking pointer arithmetic..
strPlusChar("void foo()\n"
"{\n"
" std::string temp = \"/tmp\";\n"
" std::string path = temp + '/' + \"sub\" + '/';\n"
"}\n");
ASSERT_EQUALS("", errout.str());
}
void varScope(const char code[])
{
// Tokenize..
Tokenizer tokenizer;
std::istringstream istr(code);
tokenizer.tokenize(istr, "test.cpp");
tokenizer.simplifyTokenList();
// Clear the error buffer..
errout.str("");
// Check for redundant code..
Settings settings;
settings._checkCodingStyle = true;
CheckOther checkOther(&tokenizer, &settings, this);
checkOther.checkVariableScope();
}
void varScope1()
{
varScope("unsigned short foo()\n"
"{\n"
" test_client CClient;\n"
" try\n"
" {\n"
" if (CClient.Open())\n"
" {\n"
" return 0;\n"
" }\n"
" }\n"
" catch (...)\n"
" {\n"
" return 2;\n"
" }\n"
"\n"
" try\n"
" {\n"
" CClient.Close();\n"
" }\n"
" catch (...)\n"
" {\n"
" return 2;\n"
" }\n"
"\n"
" return 1;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
}
void varScope2()
{
varScope("int foo()\n"
"{\n"
" Error e;\n"
" e.SetValue(12);\n"
" throw e;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
}
void varScope3()
{
varScope("void foo()\n"
"{\n"
" int i;\n"
" int *p = 0;\n"
" if (abc)\n"
" {\n"
" p = &i;\n"
" }\n"
" *p = 1;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
}
void varScope4()
{
varScope("void foo()\n"
"{\n"
" int i;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
}
void varScope5()
{
varScope("void f()\n"
"{\n"
" int i = 0;\n"
" if (true) {\n"
" for ( ; i < 10; ++i) ;\n"
" }\n"
"}\n");
ASSERT_EQUALS("[test.cpp:3]: (style) The scope of the variable i can be limited\n", errout.str());
}
void varScope6()
{
varScope("void f(int x)\n"
"{\n"
" int i = x;\n"
" if (a) {\n"
" x++;\n"
" }\n"
" if (b) {\n"
" c(i);\n"
" }\n"
"}\n");
ASSERT_EQUALS("", errout.str());
}
void checkNullPointer(const char code[])
{
// Tokenize..
Tokenizer tokenizer;
std::istringstream istr(code);
tokenizer.tokenize(istr, "test.cpp");
// Clear the error buffer..
errout.str("");
// Check for redundant code..
Settings settings;
settings._checkCodingStyle = true;
CheckOther checkOther(&tokenizer, &settings, this);
checkOther.nullPointer();
}
void nullpointer1()
{
checkNullPointer("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\n", errout.str());
checkNullPointer("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\n", errout.str());
checkNullPointer("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());
}
void nullpointer2()
{
// Null pointer dereference can only happen with pointers
checkNullPointer("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
void nullpointer3()
{
// errors..
checkNullPointer("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());
checkNullPointer("void foo(struct ABC *abc)\n"
"{\n"
" bar(abc->a);\n"
" if (!abc)\n"
" ;\n"
"}\n");
TODO_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());
// ok dereferencing in a condition
checkNullPointer("void foo(struct ABC *abc)\n"
"{\n"
" if (abc && abc->a);\n"
" if (!abc)\n"
" ;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
// ok to use a linked list..
checkNullPointer("void foo(struct ABC *abc)\n"
"{\n"
" abc = abc->next;\n"
" if (!abc)\n"
" ;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
// reassign struct..
checkNullPointer("void foo(struct ABC *abc)\n"
"{\n"
" a = abc->a;\n"
" abc = abc->next;\n"
" if (!abc)\n"
" ;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
checkNullPointer("void foo(struct ABC *abc)\n"
"{\n"
" a = abc->a;\n"
" f(&abc);\n"
" if (!abc)\n"
" ;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
// goto..
checkNullPointer("void foo(struct ABC *abc)\n"
"{\n"
" if (!abc)\n"
" goto out;"
" a = abc->a;\n"
" return;\n"
"out:\n"
" if (!abc)\n"
" ;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
// loops..
checkNullPointer("void freeAbc(struct ABC *abc)\n"
"{\n"
" while (abc)\n"
" {\n"
" struct ABC *next = abc->next;\n"
" if (abc) delete abc;\n"
" abc = next;\n"
" }\n"
"}\n");
ASSERT_EQUALS("", errout.str());
checkNullPointer("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());
// dynamic_cast..
checkNullPointer("void foo(ABC *abc)\n"
"{\n"
" int a = abc->a;\n"
" if (!dynamic_cast<DEF *>(abc))\n"
" ;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
}
// Dereferencing a pointer and then checking if it is null
void nullpointer4()
{
// errors..
checkNullPointer("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\n", errout.str());
checkNullPointer("void foo(int *p)\n"
"{\n"
" bar(*p);\n"
" if (!p)\n"
" ;\n"
"}\n");
TODO_ASSERT_EQUALS("[test.cpp:3]: (error) Possible null pointer dereference: p\n", errout.str());
// no error
checkNullPointer("void foo()\n"
"{\n"
" int *p;\n"
" f(&p);\n"
" if (!p)\n"
" ;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
checkNullPointer("void foo()\n"
"{\n"
" int **p = f();\n"
" if (!p)\n"
" ;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
checkNullPointer("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());
checkNullPointer("void foo(int x)\n"
"{\n"
" int a = 2 * x;"
" if (x == 0)\n"
" ;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
checkNullPointer("void foo(int *p)\n"
"{\n"
" int var1 = p ? *p : 0;\n"
" if (!p)\n"
" ;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
}
void checkOldStylePointerCast(const char code[])
{
// Tokenize..
Tokenizer tokenizer;
std::istringstream istr(code);
tokenizer.tokenize(istr, "test.cpp");
tokenizer.setVarId();
// Clear the error buffer..
errout.str("");
// Check for redundant code..
Settings settings;
settings._checkCodingStyle = true;
CheckOther checkOther(&tokenizer, &settings, this);
checkOther.warningOldStylePointerCast();
}
void oldStylePointerCast()
{
checkOldStylePointerCast("class Base;\n"
"void foo()\n"
"{\n"
" Base * b = (Base *) derived;\n"
"}\n");
ASSERT_EQUALS("[test.cpp:4]: (style) C-style pointer casting\n", errout.str());
checkOldStylePointerCast("class Base;\n"
"void foo()\n"
"{\n"
" Base * b = (const Base *) derived;\n"
"}\n");
ASSERT_EQUALS("[test.cpp:4]: (style) C-style pointer casting\n", errout.str());
checkOldStylePointerCast("class Base;\n"
"void foo()\n"
"{\n"
" Base * b = (const Base *) ( new Derived() );\n"
"}\n");
ASSERT_EQUALS("[test.cpp:4]: (style) C-style pointer casting\n", errout.str());
checkOldStylePointerCast("class Base;\n"
"void foo()\n"
"{\n"
" Base * b = (const Base *) new Derived();\n"
"}\n");
ASSERT_EQUALS("[test.cpp:4]: (style) C-style pointer casting\n", errout.str());
checkOldStylePointerCast("class Base;\n"
"void foo()\n"
"{\n"
" Base * b = (const Base *) new short[10];\n"
"}\n");
ASSERT_EQUALS("[test.cpp:4]: (style) C-style pointer casting\n", errout.str());
checkOldStylePointerCast("class B;\n"
"class A\n"
"{\n"
" virtual void abc(B *) const = 0;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
checkOldStylePointerCast("class B;\n"
"class A\n"
"{\n"
" virtual void abc(const B *) const = 0;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
}
void checkpostIncrementDecrement(const char code[])
{
// Tokenize..
Tokenizer tokenizer;
std::istringstream istr(code);
tokenizer.tokenize(istr, "test.cpp");
tokenizer.setVarId();
// Clear the error buffer..
errout.str("");
// Check for redundant code..
Settings settings;
settings._checkCodingStyle = true;
CheckOther checkOther(&tokenizer, &settings, this);
checkOther.postIncrement();
}
void postIncrementDecrementStl()
{
checkpostIncrementDecrement("void f1()\n"
"{\n"
" std::list<int>::iterator it;\n"
" for (it = ab.begin(); it != ab.end(); it++)\n"
" ;\n"
"}\n");
ASSERT_EQUALS("[test.cpp:4]: (possible style) Pre-Incrementing variable 'it' is preferred to Post-Incrementing\n", errout.str());
checkpostIncrementDecrement("void f2()\n"
"{\n"
" std::list<int>::iterator it;\n"
" for (it = ab.end(); it != ab.begin(); it--)\n"
" ;\n"
"}\n");
ASSERT_EQUALS("[test.cpp:4]: (possible style) Pre-Decrementing variable 'it' is preferred to Post-Decrementing\n", errout.str());
}
void postIncrementDecrementClass()
{
checkpostIncrementDecrement("class TestClass;\n"
"void f1()\n"
"{\n"
" TestClass tClass;\n"
" for (tClass = TestClass.begin(); tClass != TestClass.end(); tClass++)\n"
" ;\n"
"}\n");
ASSERT_EQUALS("[test.cpp:5]: (possible style) Pre-Incrementing variable 'tClass' is preferred to Post-Incrementing\n", errout.str());
checkpostIncrementDecrement("class TestClass;\n"
"void f1()\n"
"{\n"
" TestClass tClass;\n"
" for (tClass = TestClass.end(); tClass != TestClass.begin(); tClass--)\n"
" ;\n"
"}\n");
ASSERT_EQUALS("[test.cpp:5]: (possible style) Pre-Decrementing variable 'tClass' is preferred to Post-Decrementing\n", errout.str());
}
};
REGISTER_TEST(TestOther)