cppcheck/lib/check64bit.cpp

163 lines
7.1 KiB
C++

/*
* Cppcheck - A tool for static C/C++ code analysis
* Copyright (C) 2007-2018 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 "errorlogger.h"
#include "settings.h"
#include "symboldatabase.h"
#include "token.h"
#include "tokenize.h"
#include <cstddef>
//---------------------------------------------------------------------------
// CWE ids used
static const struct CWE CWE398(398U); // Indicator of Poor Code Quality
static const struct CWE CWE758(758U); // Reliance on Undefined, Unspecified, or Implementation-Defined Behavior
// Register this check class (by creating a static instance of it)
namespace {
Check64BitPortability instance;
}
void Check64BitPortability::pointerassignment()
{
if (!_settings->isEnabled(Settings::PORTABILITY))
return;
const SymbolDatabase *symbolDatabase = _tokenizer->getSymbolDatabase();
// Check return values
for (const Scope * scope : symbolDatabase->functionScopes) {
if (scope->function == nullptr || !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->bodyStart->next(); tok != scope->bodyEnd; tok = tok->next()) {
// skip nested functions
if (tok->str() == "{") {
if (tok->scope()->type == Scope::ScopeType::eFunction || tok->scope()->type == Scope::ScopeType::eLambda)
tok = tok->link();
}
if (tok->str() != "return")
continue;
if (!tok->astOperand1() || tok->astOperand1()->isNumber())
continue;
const ValueType * const returnType = tok->astOperand1()->valueType();
if (!returnType)
continue;
if (retPointer && !returnType->typeScope && returnType->pointer == 0U)
returnIntegerError(tok);
if (!retPointer && returnType->pointer >= 1U)
returnPointerError(tok);
}
}
// Check assignments
for (const Scope * scope : symbolDatabase->functionScopes) {
for (const Token *tok = scope->bodyStart; tok && tok != scope->bodyEnd; tok = tok->next()) {
if (tok->str() != "=")
continue;
const ValueType *lhstype = tok->astOperand1() ? tok->astOperand1()->valueType() : nullptr;
const ValueType *rhstype = tok->astOperand2() ? tok->astOperand2()->valueType() : nullptr;
if (!lhstype || !rhstype)
continue;
// Assign integer to pointer..
if (lhstype->pointer >= 1U &&
!tok->astOperand2()->isNumber() &&
rhstype->pointer == 0U &&
rhstype->originalTypeName.empty() &&
rhstype->type == ValueType::Type::INT)
assignmentIntegerToAddressError(tok);
// Assign pointer to integer..
if (rhstype->pointer >= 1U &&
lhstype->pointer == 0U &&
lhstype->originalTypeName.empty() &&
lhstype->isIntegral() &&
lhstype->type >= ValueType::Type::CHAR &&
lhstype->type <= ValueType::Type::INT)
assignmentAddressToIntegerError(tok);
}
}
}
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).", CWE758, false);
}
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).", CWE758, false);
}
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.", CWE758, false);
}
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.", CWE758, false);
}