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Fixed #1094 (Improve check: unusual pointer arithmetic: 'ch+str')

This commit is contained in:
Monika Lukow 2010-01-31 11:42:02 +01:00
parent 1a59e1bc68
commit 4f30468c80
2 changed files with 124 additions and 15 deletions
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85
lib/checkother.cpp
View File

@ -811,24 +811,70 @@ void CheckOther::checkIncompleteStatement()
//---------------------------------------------------------------------------
// str plus char
//
// What is checked:
// string = string + "xxx" + 'x'; OK
// string = const char * + %any%; ERR
// string = 'x' + %any%; ERR
// string = char + %any%; ERR
// const char * = "xxx" + %number%; OK
//
// where:
// string - variable of type string
// const char * - variable of type const char *
// 'x' - a character literal
// "xxx" - a string literal
// %any% - anything (variable or literal)
// %number% - a number (literal or variable)
//---------------------------------------------------------------------------
void CheckOther::strPlusChar()
{
bool charVars[10000] = {0};
char strVars[10000] = {0}; // 1 - string, 2 - const char *, 3 - number (char,int,short), 0 - other
char assignToConstChar = 0; // 1 - assigning to const char *, 2 - 'const char*'-part assigned
for (const Token *tok = _tokenizer->tokens(); tok; tok = tok->next())
{
// Declaring char variable..
if (Token::Match(tok, "char %var% [;=]"))
if (assignToConstChar)
{
if (Token::Match(tok, "%var%"))
{
unsigned int varid = tok->varId();
if (strVars[varid] == 2)
{
assignToConstChar = 2;
}
else if (!(tok->isNumber() || (strVars[varid] == 3)))
{
strPlusChar(tok);
}
}
else if (Token::Match(tok, "%str%"))
{
assignToConstChar = 2;
}
else if (Token::Match(tok, ";"))
{
// 'const char *'-part was not found
if (assignToConstChar != 2)
{
strPlusChar(tok);
}
assignToConstChar = 0;
}
else if (!(Token::Match(tok, "[+=]") || tok->isNumber()))
{
strPlusChar(tok);
}
}
else if (Token::Match(tok, "string %var% [;=]"))
{
unsigned int varid = tok->next()->varId();
if (varid > 0 && varid < 10000)
charVars[varid] = true;
strVars[varid] = 1;
}
//
else if (Token::Match(tok, "[=(] %str% + %any%"))
else if (Token::Match(tok, "const char * %var% [;=]"))
{
// char constant..
const char *s = tok->strAt(3);
@ -837,8 +883,29 @@ void CheckOther::strPlusChar()
// char variable..
unsigned int varid = tok->tokAt(3)->varId();
if (varid > 0 && varid < 10000 && charVars[varid])
strPlusChar(tok->next());
if (varid > 0 && varid < 10000)
strVars[varid] = 2;
}
else if (Token::Match(tok, "char|int|short %var% [;=]"))
{
unsigned int varid = tok->next()->varId();
if (varid > 0 && varid < 10000)
strVars[varid] = 3;
}
else if (Token::Match(tok, "%var% = %any% + %any%") &&
(strVars[tok->varId()] == 1))
{
// string =
unsigned int varidAny = tok->tokAt(2)->varId();
// first %any% has to be a variable of type string
if (!strVars[varidAny])
strPlusChar(tok->tokAt(3));
}
else if (Token::Match(tok, "%var% = %any%") &&
(strVars[tok->varId()] == 2))
{
// const char * =
assignToConstChar = 1;
}
}
}

54
test/testother.cpp
View File

@ -49,9 +49,10 @@ private:
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(strPlusChar1); // "/usr" + '/'
TEST_CASE(strPlusChar2); // "/usr" + ch
TEST_CASE(strPlusChar3); // ok : path + "/sub" + '/'; err: '/' + path + "/sub"
TEST_CASE(strPlusChar4); // ok : <const char *> + <number>
TEST_CASE(varScope1);
TEST_CASE(varScope2);
@ -423,6 +424,12 @@ private:
" const char *p = \"/usr\" + '/';\n"
"}\n");
ASSERT_EQUALS("[test.cpp:3]: (error) Unusual pointer arithmetic\n", errout.str());
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()
@ -430,10 +437,23 @@ private:
// Strange looking pointer arithmetic..
strPlusChar("void foo()\n"
"{\n"
" char ch = '/';\n"
" const char *p = \"/usr\" + ch;\n"
" int x = 1;\n"
" const char *p = \"/usr\" + x;\n"
"}\n");
ASSERT_EQUALS("[test.cpp:4]: (error) Unusual pointer arithmetic\n", errout.str());
ASSERT_EQUALS("", errout.str());
strPlusChar("void foo()\n"
"{\n"
" const char *p = \"/usr\" + 1;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
strPlusChar("void foo()\n"
"{\n"
" char ch = '/';\n"
" const char *p = ch + \"/usr\";\n"
"}\n");
ASSERT_EQUALS("", errout.str());
}
void strPlusChar3()
@ -445,9 +465,31 @@ private:
" std::string path = temp + '/' + \"sub\" + '/';\n"
"}\n");
ASSERT_EQUALS("", errout.str());
strPlusChar("void foo()\n"
"{\n"
" std::string path = '/' + \"sub\" + '/';\n"
"}\n");
ASSERT_EQUALS("[test.cpp:3]: (error) Unusual pointer arithmetic\n", errout.str());
}
void strPlusChar4()
{
// Strange looking pointer arithmetic..
strPlusChar("void foo()\n"
"{\n"
" const char *p = \"abcd\" + 1;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
strPlusChar("void foo()\n"
"{\n"
" char ch = 1;\n"
" const char *p = \"abcd\";\n"
" const char *s = ch + p;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
}
void varScope(const char code[])
{