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Refactoring the uninitialized variable / null pointer checks so they use a common function to inspect function calls

This commit is contained in:
Daniel Marjamäki 2009-12-23 19:51:32 +01:00
parent a7d48f2eb4
commit ea51c3e098
2 changed files with 83 additions and 10 deletions
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86
lib/checkother.cpp
View File

@ -1118,6 +1118,68 @@ void CheckOther::nullPointer()
}
/**
* \brief parse a function call and extract information about variable usage
* \param tok first token
* \param var variables that the function read / write.
* \param value 0 => invalid with null pointers as parameter.
* 1-.. => invalid with uninitialized data.
*/
static void parseFunctionCall(const Token &tok, std::list<const Token *> &var, unsigned char value)
{
// standard functions that dereference first parameter..
// both uninitialized data and null pointers are invalid.
static std::set<std::string> functionNames1;
if (functionNames1.empty())
{
functionNames1.insert("memchr");
functionNames1.insert("memcmp");
functionNames1.insert("strcat");
functionNames1.insert("strncat");
functionNames1.insert("strchr");
functionNames1.insert("strrchr");
functionNames1.insert("strcmp");
functionNames1.insert("strncmp");
functionNames1.insert("strdup");
functionNames1.insert("strlen");
functionNames1.insert("strstr");
}
// standard functions that dereference second parameter..
// both uninitialized data and null pointers are invalid.
static std::set<std::string> functionNames2;
if (functionNames2.empty())
{
functionNames2.insert("memcmp");
functionNames2.insert("memcpy");
functionNames2.insert("memmove");
functionNames2.insert("strcat");
functionNames2.insert("strncat");
functionNames2.insert("strcmp");
functionNames2.insert("strncmp");
functionNames2.insert("strcpy");
functionNames2.insert("strncpy");
functionNames2.insert("strstr");
}
// 1st parameter..
if (Token::Match(&tok, "%var% ( %var% ,|)") && tok.tokAt(2)->varId() > 0)
{
if (functionNames1.find(tok.str()) != functionNames1.end())
var.push_back(tok.tokAt(2));
else if (value == 0 && Token::Match(&tok, "memchr|memcmp|memcpy|memmove|memset|strcpy|printf|sprintf|snprintf"))
var.push_back(tok.tokAt(2));
else if (Token::Match(&tok, "free|kfree|fclose|fflush"))
var.push_back(tok.tokAt(2));
}
// 2nd parameter..
if (Token::Match(&tok, "%var% ( %any% , %var% ,|)") && tok.tokAt(4)->varId() > 0)
{
if (functionNames2.find(tok.str()) != functionNames2.end())
var.push_back(tok.tokAt(4));
}
}
class CheckNullpointer : public ExecutionPath
@ -1190,6 +1252,15 @@ private:
return vartok->next();
}
if (Token::Match(tok.previous(), "[;{}] %var% ("))
{
// parse usage..
std::list<const Token *> var;
parseFunctionCall(tok, var, 0);
for (std::list<const Token *>::const_iterator it = var.begin(); it != var.end(); ++it)
dereference(foundError, checks, *it);
}
if (tok.varId() != 0)
{
if (Token::Match(tok.previous(), "[;{}=] %var% = 0 ;"))
@ -1397,17 +1468,12 @@ private:
if (Token::Match(&tok, "%var% ("))
{
// reading 1st parameter..
if (Token::Match(&tok, "strcat|strncat|strchr|strrchr|strstr|strlen|strdup ( %var%"))
// parse usage..
{
use_array(foundError, checks, tok.tokAt(2));
}
// reading 2nd parameter..
if (Token::Match(&tok, "strcpy|strstr ( %any% , %var% ) ") ||
Token::Match(&tok, "strncpy ( %any% , %var% ,"))
{
use_array(foundError, checks, tok.tokAt(4));
std::list<const Token *> var;
parseFunctionCall(tok, var, 1);
for (std::list<const Token *>::const_iterator it = var.begin(); it != var.end(); ++it)
use_array(foundError, checks, *it);
}
// strncpy doesn't 0-terminate first parameter

7
test/testother.cpp
View File

@ -1211,6 +1211,13 @@ private:
"}\n");
ASSERT_EQUALS("", errout.str());
checkUninitVar("void f()\n"
"{\n"
" FILE *f;\n"
" fflush(f);\n"
"}\n");
ASSERT_EQUALS("error", errout.str());
// arrays..
checkUninitVar("void f()\n"
"{\n"