cppcheck/lib/check64bit.cpp

146 lines
6.6 KiB
C++

/*
* Cppcheck - A tool for static C/C++ code analysis
* Copyright (C) 2007-2013 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/>.
*/
//---------------------------------------------------------------------------
// 64-bit portability
//---------------------------------------------------------------------------
#include "check64bit.h"
#include "symboldatabase.h"
//---------------------------------------------------------------------------
// Register this check class (by creating a static instance of it)
namespace {
Check64BitPortability instance;
}
/** Is given variable a pointer or array? */
static bool isaddr(const Variable *var)
{
return (var && (var->isPointer() || var->isArray()));
}
/** Is given variable an integer variable */
static bool isint(const Variable *var)
{
return (var && Token::Match(var->nameToken()->previous(), "int|long|DWORD %var% !!["));
}
void Check64BitPortability::pointerassignment()
{
if (!_settings->isEnabled("portability"))
return;
const SymbolDatabase *symbolDatabase = _tokenizer->getSymbolDatabase();
// Check return values
const std::size_t functions = symbolDatabase->functionScopes.size();
for (std::size_t i = 0; i < functions; ++i) {
const Scope * scope = symbolDatabase->functionScopes[i];
if (scope->function == 0 || !scope->function->hasBody) // We only look for functions with a body
continue;
bool retPointer = false;
if (scope->function->token->strAt(-1) == "*") // Function returns a pointer
retPointer = true;
else if (Token::Match(scope->function->token->previous(), "int|long|DWORD")) // Function returns an integer
;
else
continue;
for (const Token* tok = scope->classStart->next(); tok != scope->classEnd; tok = tok->next()) {
if (Token::Match(tok, "return %var% [;+]")) {
const Variable *var = symbolDatabase->getVariableFromVarId(tok->next()->varId());
if (retPointer && isint(var))
returnIntegerError(tok);
else if (!retPointer && isaddr(var))
returnPointerError(tok);
}
}
}
// Check assignments
for (std::size_t i = 0; i < functions; ++i) {
const Scope * scope = symbolDatabase->functionScopes[i];
for (const Token *tok = scope->classStart; tok && tok != scope->classEnd; tok = tok->next()) {
if (Token::Match(tok, "[;{}] %var% = %var% [;+]")) {
const Variable *var1(symbolDatabase->getVariableFromVarId(tok->next()->varId()));
const Variable *var2(symbolDatabase->getVariableFromVarId(tok->tokAt(3)->varId()));
if (isaddr(var1) && isint(var2) && tok->strAt(4) != "+")
assignmentIntegerToAddressError(tok->next());
else if (isint(var1) && isaddr(var2) && !tok->tokAt(3)->isPointerCompare()) {
// assigning address => warning
// some trivial addition => warning
if (Token::Match(tok->tokAt(4), "+ %any% !!;"))
continue;
assignmentAddressToIntegerError(tok->next());
}
}
}
}
}
void Check64BitPortability::assignmentAddressToIntegerError(const Token *tok)
{
reportError(tok, Severity::portability,
"AssignmentAddressToInteger",
"Assigning a pointer to an integer is not portable.\n"
"Assigning a pointer to an integer (int/long/etc) is not portable across different platforms and "
"compilers. For example in 32-bit Windows and linux they are same width, but in 64-bit Windows and linux "
"they are of different width. In worst case you end up assigning 64-bit address to 32-bit integer. The safe "
"way is to store addresses only in pointer types (or typedefs like uintptr_t).");
}
void Check64BitPortability::assignmentIntegerToAddressError(const Token *tok)
{
reportError(tok, Severity::portability,
"AssignmentIntegerToAddress",
"Assigning an integer to a pointer is not portable.\n"
"Assigning an integer (int/long/etc) to a pointer is not portable across different platforms and "
"compilers. For example in 32-bit Windows and linux they are same width, but in 64-bit Windows and linux "
"they are of different width. In worst case you end up assigning 64-bit integer to 32-bit pointer. The safe "
"way is to store addresses only in pointer types (or typedefs like uintptr_t).");
}
void Check64BitPortability::returnPointerError(const Token *tok)
{
reportError(tok, Severity::portability,
"CastAddressToIntegerAtReturn",
"Returning an address value in a function with integer return type is not portable.\n"
"Returning an address value in a function with integer (int/long/etc) return type is not portable across "
"different platforms and compilers. For example in 32-bit Windows and Linux they are same width, but in "
"64-bit Windows and Linux they are of different width. In worst case you end up casting 64-bit address down "
"to 32-bit integer. The safe way is to always return an integer.");
}
void Check64BitPortability::returnIntegerError(const Token *tok)
{
reportError(tok, Severity::portability,
"CastIntegerToAddressAtReturn",
"Returning an integer in a function with pointer return type is not portable.\n"
"Returning an integer (int/long/etc) in a function with pointer return type is not portable across different "
"platforms and compilers. For example in 32-bit Windows and Linux they are same width, but in 64-bit Windows "
"and Linux they are of different width. In worst case you end up casting 64-bit integer down to 32-bit pointer. "
"The safe way is to always return a pointer.");
}