1668 lines
79 KiB
C++
1668 lines
79 KiB
C++
/*
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* Cppcheck - A tool for static C/C++ code analysis
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* Copyright (C) 2007-2018 Cppcheck team.
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*
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* This program is free software: you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation, either version 3 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program. If not, see <http://www.gnu.org/licenses/>.
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*/
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#include "checkstl.h"
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#include "checknullpointer.h"
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#include "errorlogger.h"
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#include "settings.h"
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#include "standards.h"
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#include "symboldatabase.h"
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#include "token.h"
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#include "utils.h"
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#include <cstddef>
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#include <list>
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#include <set>
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#include <sstream>
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#include <utility>
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// Register this check class (by creating a static instance of it)
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namespace {
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CheckStl instance;
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}
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// CWE IDs used:
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static const struct CWE CWE398(398U); // Indicator of Poor Code Quality
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static const struct CWE CWE597(597U); // Use of Wrong Operator in String Comparison
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static const struct CWE CWE628(628U); // Function Call with Incorrectly Specified Arguments
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static const struct CWE CWE664(664U); // Improper Control of a Resource Through its Lifetime
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static const struct CWE CWE704(704U); // Incorrect Type Conversion or Cast
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static const struct CWE CWE762(762U); // Mismatched Memory Management Routines
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static const struct CWE CWE786(786U); // Access of Memory Location Before Start of Buffer
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static const struct CWE CWE788(788U); // Access of Memory Location After End of Buffer
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static const struct CWE CWE825(825U); // Expired Pointer Dereference
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static const struct CWE CWE834(834U); // Excessive Iteration
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// Error message for bad iterator usage..
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void CheckStl::invalidIteratorError(const Token *tok, const std::string &iteratorName)
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{
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reportError(tok, Severity::error, "invalidIterator1", "Invalid iterator: " + iteratorName, CWE664, false);
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}
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void CheckStl::iteratorsError(const Token *tok, const std::string &container1, const std::string &container2)
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{
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reportError(tok, Severity::error, "iterators", "Same iterator is used with different containers '" + container1 + "' and '" + container2 + "'.", CWE664, false);
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}
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// Error message used when dereferencing an iterator that has been erased..
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void CheckStl::dereferenceErasedError(const Token *erased, const Token* deref, const std::string &itername, bool inconclusive)
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{
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if (erased) {
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std::list<const Token*> callstack;
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callstack.push_back(deref);
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callstack.push_back(erased);
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reportError(callstack, Severity::error, "eraseDereference",
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"Iterator '" + itername + "' used after element has been erased.\n"
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"The iterator '" + itername + "' is invalid after the element it pointed to has been erased. "
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"Dereferencing or comparing it with another iterator is invalid operation.", CWE664, inconclusive);
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} else {
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reportError(deref, Severity::error, "eraseDereference",
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"Invalid iterator '" + itername + "' used.\n"
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"The iterator '" + itername + "' is invalid before being assigned. "
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"Dereferencing or comparing it with another iterator is invalid operation.", CWE664, inconclusive);
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}
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}
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static const Token *skipMembers(const Token *tok)
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{
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while (Token::Match(tok, "%name% ."))
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tok = tok->tokAt(2);
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return tok;
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}
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static bool isIterator(const Variable *var, bool& inconclusiveType)
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{
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// Check that its an iterator
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if (!var || !var->isLocal() || !Token::Match(var->typeEndToken(), "iterator|const_iterator|reverse_iterator|const_reverse_iterator|auto"))
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return false;
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inconclusiveType = false;
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if (var->typeEndToken()->str() == "auto")
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return (var->nameToken()->valueType() && var->nameToken()->valueType()->type == ValueType::Type::ITERATOR);
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if (var->type()) { // If it is defined, ensure that it is defined like an iterator
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// look for operator* and operator++
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const Function* end = var->type()->getFunction("operator*");
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const Function* incOperator = var->type()->getFunction("operator++");
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if (!end || end->argCount() > 0 || !incOperator) {
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return false;
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} else {
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inconclusiveType = true; // heuristics only
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}
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}
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return true;
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}
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static std::string getContainerName(const Token *containerToken)
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{
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if (!containerToken)
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return std::string();
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std::string ret(containerToken->str());
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for (const Token *nametok = containerToken; nametok; nametok = nametok->tokAt(-2)) {
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if (!Token::Match(nametok->tokAt(-2), "%name% ."))
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break;
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ret = nametok->strAt(-2) + '.' + ret;
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}
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return ret;
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}
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void CheckStl::iterators()
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{
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const SymbolDatabase *symbolDatabase = _tokenizer->getSymbolDatabase();
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for (unsigned int iteratorId = 1; iteratorId < symbolDatabase->getVariableListSize(); iteratorId++) {
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const Variable* var = symbolDatabase->getVariableFromVarId(iteratorId);
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bool inconclusiveType=false;
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if (!isIterator(var, inconclusiveType))
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continue;
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// the validIterator flag says if the iterator has a valid value or not
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bool validIterator = Token::Match(var->nameToken()->next(), "[(=:]");
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const Scope* invalidationScope = nullptr;
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// The container this iterator can be used with
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const Token* containerToken = nullptr;
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const Scope* containerAssignScope = nullptr;
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// When "validatingToken" is reached the validIterator is set to true
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const Token* validatingToken = nullptr;
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const Token* eraseToken = nullptr;
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// Scan through the rest of the code and see if the iterator is
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// used against other containers.
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for (const Token *tok2 = var->nameToken(); tok2 && tok2 != var->scope()->classEnd; tok2 = tok2->next()) {
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if (invalidationScope && tok2 == invalidationScope->classEnd)
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validIterator = true; // Assume that the iterator becomes valid again
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if (containerAssignScope && tok2 == containerAssignScope->classEnd)
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containerToken = nullptr; // We don't know which containers might be used with the iterator
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if (tok2 == validatingToken) {
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validIterator = true;
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eraseToken = nullptr;
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invalidationScope = nullptr;
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}
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// Is iterator compared against different container?
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if (tok2->isComparisonOp() && containerToken && tok2->astOperand1() && tok2->astOperand2()) {
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const Token *other = nullptr;
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if (tok2->astOperand1()->varId() == iteratorId)
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other = tok2->astOperand2()->tokAt(-3);
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else if (tok2->astOperand2()->varId() == iteratorId)
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other = tok2->astOperand1()->tokAt(-3);
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if (Token::Match(other, "%name% . end|rend|cend|crend ( )") && other->varId() != containerToken->varId())
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iteratorsError(tok2, getContainerName(containerToken), getContainerName(other));
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}
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// Is the iterator used in a insert/erase operation?
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else if (Token::Match(tok2, "%name% . insert|erase ( *| %varid% )|,", iteratorId)) {
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const Token* itTok = tok2->tokAt(4);
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if (itTok->str() == "*") {
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if (tok2->strAt(2) == "insert")
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continue;
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itTok = itTok->next();
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}
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// It is bad to insert/erase an invalid iterator
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if (!validIterator)
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invalidIteratorError(tok2, itTok->str());
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// If insert/erase is used on different container then
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// report an error
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if (containerToken && tok2->varId() != containerToken->varId()) {
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// skip error message if container is a set..
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const Variable *variableInfo = tok2->variable();
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const Token *decltok = variableInfo ? variableInfo->typeStartToken() : nullptr;
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if (Token::simpleMatch(decltok, "std :: set"))
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continue; // No warning
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// skip error message if the iterator is erased/inserted by value
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if (itTok->previous()->str() == "*")
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continue;
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// inserting iterator range..
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if (tok2->strAt(2) == "insert") {
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const Token *par2 = itTok->nextArgument();
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if (!par2 || par2->nextArgument())
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continue;
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while (par2->str() != ")") {
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if (par2->varId() == containerToken->varId())
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break;
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bool inconclusiveType2=false;
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if (isIterator(par2->variable(), inconclusiveType2))
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break; // TODO: check if iterator points at same container
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if (par2->str() == "(")
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par2 = par2->link();
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par2 = par2->next();
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}
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if (par2->str() != ")")
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continue;
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}
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// Show error message, mismatching iterator is used.
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iteratorsError(tok2, getContainerName(containerToken), getContainerName(tok2));
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}
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// invalidate the iterator if it is erased
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else if (tok2->strAt(2) == "erase" && (tok2->strAt(4) != "*" || (containerToken && tok2->varId() == containerToken->varId()))) {
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validIterator = false;
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eraseToken = tok2;
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invalidationScope = tok2->scope();
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}
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// skip the operation
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tok2 = itTok->next();
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}
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// it = foo.erase(..
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// taking the result of an erase is ok
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else if (Token::Match(tok2, "%varid% = %name% .", iteratorId) &&
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Token::simpleMatch(skipMembers(tok2->tokAt(2)), "erase (")) {
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// the returned iterator is valid
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validatingToken = skipMembers(tok2->tokAt(2))->linkAt(1);
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tok2 = validatingToken->link();
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}
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// Reassign the iterator
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else if (Token::Match(tok2, "%varid% = %name% .", iteratorId) &&
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Token::Match(skipMembers(tok2->tokAt(2)), "begin|rbegin|cbegin|crbegin|find (")) {
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validatingToken = skipMembers(tok2->tokAt(2))->linkAt(1);
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containerToken = skipMembers(tok2->tokAt(2))->tokAt(-2);
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if (containerToken->varId() == 0 || Token::simpleMatch(validatingToken, ") ."))
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containerToken = nullptr;
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containerAssignScope = tok2->scope();
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// skip ahead
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tok2 = validatingToken->link();
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}
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// Reassign the iterator
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else if (Token::Match(tok2, "%varid% =", iteratorId)) {
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// Assume that the iterator becomes valid.
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// TODO: add checking that checks if the iterator becomes valid or not
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validatingToken = Token::findmatch(tok2->tokAt(2), "[;)]");
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// skip ahead
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tok2 = tok2->tokAt(2);
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}
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// Passing iterator to function. Iterator might be initialized
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else if (Token::Match(tok2, "%varid% ,|)", iteratorId)) {
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validIterator = true;
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}
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// Dereferencing invalid iterator?
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else if (!validIterator && Token::Match(tok2, "* %varid%", iteratorId)) {
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dereferenceErasedError(eraseToken, tok2, tok2->strAt(1), inconclusiveType);
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tok2 = tok2->next();
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} else if (!validIterator && Token::Match(tok2, "%varid% . %name%", iteratorId)) {
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dereferenceErasedError(eraseToken, tok2, tok2->str(), inconclusiveType);
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tok2 = tok2->tokAt(2);
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}
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// bailout handling. Assume that the iterator becomes valid if we see return/break.
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// TODO: better handling
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else if (tok2->scope() == invalidationScope && Token::Match(tok2, "return|break|continue")) {
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validatingToken = Token::findsimplematch(tok2->next(), ";");
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}
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// bailout handling. Assume that the iterator becomes valid if we see else.
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// TODO: better handling
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else if (tok2->str() == "else") {
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validIterator = true;
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}
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}
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}
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}
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// Error message for bad iterator usage..
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void CheckStl::mismatchingContainersError(const Token *tok)
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{
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reportError(tok, Severity::error, "mismatchingContainers", "Iterators of different containers are used together.", CWE664, false);
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}
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static const std::set<std::string> algorithm2 = make_container< std::set<std::string> >() // func(begin1, end1
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<< "binary_search" << "copy" << "copy_if" << "equal_range"
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<< "generate" << "is_heap" << "is_heap_until" << "is_partitioned"
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<< "is_permutation" << "is_sorted" << "is_sorted_until" << "lower_bound" << "make_heap" << "max_element" << "minmax_element"
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<< "min_element" << "mismatch" << "move" << "move_backward" << "next_permutation" << "partition" << "partition_copy"
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<< "partition_point" << "pop_heap" << "prev_permutation" << "push_heap" << "random_shuffle" << "remove" << "remove_copy"
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<< "remove_copy_if" << "remove_if" << "replace" << "replace_copy" << "replace_copy_if" << "replace_if" << "reverse" << "reverse_copy"
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<< "shuffle" << "sort" << "sort_heap" << "stable_partition" << "stable_sort" << "swap_ranges" << "transform" << "unique"
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<< "unique_copy" << "upper_bound" << "string" << "wstring" << "u16string" << "u32string";
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static const std::set<std::string> algorithm22 = make_container< std::set<std::string> >() // func(begin1 << end1 << begin2 << end2
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<< "includes" << "lexicographical_compare" << "merge" << "partial_sort_copy"
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<< "set_difference" << "set_intersection" << "set_symmetric_difference" << "set_union";
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static const std::set<std::string> algorithm1x1 = make_container< std::set<std::string> >() // func(begin1 << x << end1
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<< "nth_element" << "partial_sort" << "rotate" << "rotate_copy";
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static const std::string iteratorBeginFuncPattern = "begin|cbegin|rbegin|crbegin";
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static const std::string iteratorEndFuncPattern = "end|cend|rend|crend";
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static const std::string pattern1x1_1 = "%name% . " + iteratorBeginFuncPattern + " ( ) , ";
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static const std::string pattern1x1_2 = "%name% . " + iteratorEndFuncPattern + " ( ) ,|)";
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static const std::string pattern2 = pattern1x1_1 + pattern1x1_2;
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static const Variable *getContainer(const Token *argtok)
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{
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while (argtok && argtok->astOperand1())
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argtok = argtok->astOperand1();
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if (!Token::Match(argtok, "%var% . begin|end|rbegin|rend ( )")) // TODO: use Library yield
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return nullptr;
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const Variable *var = argtok->variable();
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if (var && Token::simpleMatch(var->typeStartToken(), "std ::"))
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return var;
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return nullptr;
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}
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void CheckStl::mismatchingContainers()
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{
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// Check if different containers are used in various calls of standard functions
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const SymbolDatabase *symbolDatabase = _tokenizer->getSymbolDatabase();
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const std::size_t functions = symbolDatabase->functionScopes.size();
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for (std::size_t ii = 0; ii < functions; ++ii) {
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const Scope * scope = symbolDatabase->functionScopes[ii];
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for (const Token* tok = scope->classStart->next(); tok != scope->classEnd; tok = tok->next()) {
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if (!Token::Match(tok, "%name% ( !!)"))
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continue;
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const Token * const ftok = tok;
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const Token * const arg1 = tok->tokAt(2);
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int argnr = 1;
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std::map<const Variable *, unsigned int> containerNr;
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for (const Token *argTok = arg1; argTok; argTok = argTok->nextArgument()) {
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const Library::ArgumentChecks::IteratorInfo *i = _settings->library.getArgIteratorInfo(ftok,argnr++);
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if (!i)
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continue;
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const Variable *c = getContainer(argTok);
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if (!c)
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continue;
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std::map<const Variable *, unsigned int>::const_iterator it = containerNr.find(c);
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if (it == containerNr.end()) {
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for (it = containerNr.begin(); it != containerNr.end(); ++it) {
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if (it->second == i->container) {
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mismatchingContainersError(argTok);
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break;
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}
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}
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containerNr[c] = i->container;
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} else if (it->second != i->container) {
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mismatchingContainersError(argTok);
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}
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}
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const int ret = _settings->library.returnValueContainer(ftok);
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if (ret != -1 && Token::Match(ftok->next()->astParent(), "==|!=")) {
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const Token *parent = ftok->next()->astParent();
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const Token *other = (parent->astOperand1() == ftok->next()) ? parent->astOperand2() : parent->astOperand1();
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const Variable *c = getContainer(other);
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if (c) {
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const std::map<const Variable *, unsigned int>::const_iterator it = containerNr.find(c);
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if (it == containerNr.end() || it->second != ret)
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mismatchingContainersError(other);
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}
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}
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}
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}
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for (unsigned int varid = 0; varid < symbolDatabase->getVariableListSize(); varid++) {
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const Variable* var = symbolDatabase->getVariableFromVarId(varid);
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if (var && var->isStlStringType() && Token::Match(var->nameToken(), "%var% (") && Token::Match(var->nameToken()->tokAt(2), pattern2.c_str())) {
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if (var->nameToken()->strAt(2) != var->nameToken()->strAt(8)) {
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mismatchingContainersError(var->nameToken());
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}
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}
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}
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}
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void CheckStl::stlOutOfBounds()
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{
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const SymbolDatabase* const symbolDatabase = _tokenizer->getSymbolDatabase();
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// Scan through all scopes..
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for (std::list<Scope>::const_iterator i = symbolDatabase->scopeList.begin(); i != symbolDatabase->scopeList.end(); ++i) {
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const Token* tok = i->classDef;
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// only interested in conditions
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if ((i->type != Scope::eFor && i->type != Scope::eWhile && i->type != Scope::eIf && i->type != Scope::eDo) || !tok)
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continue;
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if (i->type == Scope::eFor)
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tok = Token::findsimplematch(tok->tokAt(2), ";");
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else if (i->type == Scope::eDo) {
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tok = tok->linkAt(1)->tokAt(2);
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} else
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tok = tok->next();
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if (!tok)
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continue;
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tok = tok->next();
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// check if the for loop condition is wrong
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if (!Token::Match(tok, "%var% <= %var% . %name% ( ) ;|)|%oror%"))
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continue;
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// Is it a vector?
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const Variable *var = tok->tokAt(2)->variable();
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if (!var)
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continue;
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const Library::Container* container = _settings->library.detectContainer(var->typeStartToken());
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if (!container)
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continue;
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if (container->getYield(tok->strAt(4)) != Library::Container::SIZE)
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continue;
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// variable id for loop variable.
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const unsigned int numId = tok->varId();
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// variable id for the container variable
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const unsigned int declarationId = var->declarationId();
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for (const Token *tok3 = i->classStart; tok3 && tok3 != i->classEnd; tok3 = tok3->next()) {
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if (tok3->varId() == declarationId) {
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tok3 = tok3->next();
|
|
if (Token::Match(tok3, ". %name% ( )")) {
|
|
if (container->getYield(tok3->strAt(1)) == Library::Container::SIZE)
|
|
break;
|
|
} else if (container->arrayLike_indexOp && Token::Match(tok3, "[ %varid% ]", numId))
|
|
stlOutOfBoundsError(tok3, tok3->strAt(1), var->name(), false);
|
|
else if (Token::Match(tok3, ". %name% ( %varid% )", numId)) {
|
|
const Library::Container::Yield yield = container->getYield(tok3->strAt(1));
|
|
if (yield == Library::Container::AT_INDEX)
|
|
stlOutOfBoundsError(tok3, tok3->strAt(3), var->name(), true);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
void CheckStl::stlOutOfBoundsError(const Token *tok, const std::string &num, const std::string &var, bool at)
|
|
{
|
|
if (at)
|
|
reportError(tok, Severity::error, "stlOutOfBounds", "When " + num + "==" + var + ".size(), " + var + ".at(" + num + ") is out of bounds.", CWE788, false);
|
|
else
|
|
reportError(tok, Severity::error, "stlOutOfBounds", "When " + num + "==" + var + ".size(), " + var + "[" + num + "] is out of bounds.", CWE788, false);
|
|
}
|
|
|
|
void CheckStl::negativeIndex()
|
|
{
|
|
// Negative index is out of bounds..
|
|
const SymbolDatabase* const symbolDatabase = _tokenizer->getSymbolDatabase();
|
|
const std::size_t functions = symbolDatabase->functionScopes.size();
|
|
for (std::size_t ii = 0; ii < functions; ++ii) {
|
|
const Scope * scope = symbolDatabase->functionScopes[ii];
|
|
for (const Token* tok = scope->classStart->next(); tok != scope->classEnd; tok = tok->next()) {
|
|
if (!Token::Match(tok, "%var% [") || WRONG_DATA(!tok->next()->astOperand2(), tok))
|
|
continue;
|
|
const Variable * const var = tok->variable();
|
|
if (!var || tok == var->nameToken())
|
|
continue;
|
|
const Library::Container * const container = _settings->library.detectContainer(var->typeStartToken());
|
|
if (!container || !container->arrayLike_indexOp)
|
|
continue;
|
|
const ValueFlow::Value *index = tok->next()->astOperand2()->getValueLE(-1, _settings);
|
|
if (!index)
|
|
continue;
|
|
negativeIndexError(tok, *index);
|
|
}
|
|
}
|
|
}
|
|
|
|
void CheckStl::negativeIndexError(const Token *tok, const ValueFlow::Value &index)
|
|
{
|
|
const ErrorPath errorPath = getErrorPath(tok, &index, "Negative array index");
|
|
std::ostringstream errmsg;
|
|
if (index.condition)
|
|
errmsg << ValueFlow::eitherTheConditionIsRedundant(index.condition)
|
|
<< ", otherwise there is negative array index " << index.intvalue << ".";
|
|
else
|
|
errmsg << "Array index " << index.intvalue << " is out of bounds.";
|
|
reportError(errorPath, index.errorSeverity() ? Severity::error : Severity::warning, "negativeContainerIndex", errmsg.str(), CWE786, index.isInconclusive());
|
|
}
|
|
|
|
void CheckStl::erase()
|
|
{
|
|
const SymbolDatabase* const symbolDatabase = _tokenizer->getSymbolDatabase();
|
|
|
|
for (std::list<Scope>::const_iterator i = symbolDatabase->scopeList.begin(); i != symbolDatabase->scopeList.end(); ++i) {
|
|
if (i->type == Scope::eFor && Token::simpleMatch(i->classDef, "for (")) {
|
|
const Token *tok = i->classDef->linkAt(1);
|
|
if (!Token::Match(tok->tokAt(-3), "; ++| %var% ++| ) {"))
|
|
continue;
|
|
tok = tok->previous();
|
|
if (!tok->isName())
|
|
tok = tok->previous();
|
|
eraseCheckLoopVar(*i, tok->variable());
|
|
} else if (i->type == Scope::eWhile && Token::Match(i->classDef, "while ( %var% !=")) {
|
|
eraseCheckLoopVar(*i, i->classDef->tokAt(2)->variable());
|
|
}
|
|
}
|
|
}
|
|
|
|
void CheckStl::eraseCheckLoopVar(const Scope &scope, const Variable *var)
|
|
{
|
|
bool inconclusiveType=false;
|
|
if (!isIterator(var, inconclusiveType))
|
|
return;
|
|
for (const Token *tok = scope.classStart; tok != scope.classEnd; tok = tok->next()) {
|
|
if (tok->str() != "(")
|
|
continue;
|
|
if (!Token::Match(tok->tokAt(-2), ". erase ( ++| %varid% )", var->declarationId()))
|
|
continue;
|
|
if (Token::simpleMatch(tok->astParent(), "="))
|
|
continue;
|
|
// Iterator is invalid..
|
|
unsigned int indentlevel = 0U;
|
|
const Token *tok2 = tok->link();
|
|
for (; tok2 != scope.classEnd; tok2 = tok2->next()) {
|
|
if (tok2->str() == "{") {
|
|
++indentlevel;
|
|
continue;
|
|
}
|
|
if (tok2->str() == "}") {
|
|
if (indentlevel > 0U)
|
|
--indentlevel;
|
|
else if (Token::simpleMatch(tok2, "} else {"))
|
|
tok2 = tok2->linkAt(2);
|
|
continue;
|
|
}
|
|
if (tok2->varId() == var->declarationId()) {
|
|
if (Token::simpleMatch(tok2->next(), "="))
|
|
break;
|
|
dereferenceErasedError(tok, tok2, tok2->str(), inconclusiveType);
|
|
break;
|
|
}
|
|
if (indentlevel == 0U && Token::Match(tok2, "break|return|goto"))
|
|
break;
|
|
}
|
|
if (tok2 == scope.classEnd)
|
|
dereferenceErasedError(tok, scope.classDef, var->nameToken()->str(), inconclusiveType);
|
|
}
|
|
}
|
|
|
|
void CheckStl::pushback()
|
|
{
|
|
// Pointer can become invalid after push_back, push_front, reserve or resize..
|
|
const SymbolDatabase* const symbolDatabase = _tokenizer->getSymbolDatabase();
|
|
const std::size_t functions = symbolDatabase->functionScopes.size();
|
|
for (std::size_t i = 0; i < functions; ++i) {
|
|
const Scope * scope = symbolDatabase->functionScopes[i];
|
|
for (const Token* tok = scope->classStart->next(); tok != scope->classEnd; tok = tok->next()) {
|
|
if (Token::Match(tok, "%var% = & %var% [")) {
|
|
// Skip it directly if it is a pointer or an array
|
|
const Token* containerTok = tok->tokAt(3);
|
|
if (containerTok->variable() && containerTok->variable()->isArrayOrPointer())
|
|
continue;
|
|
|
|
// Variable id for pointer
|
|
const unsigned int pointerId(tok->varId());
|
|
|
|
bool invalidPointer = false;
|
|
const Token* function = nullptr;
|
|
const Token* end2 = tok->scope()->classEnd;
|
|
for (const Token *tok2 = tok; tok2 != end2; tok2 = tok2->next()) {
|
|
// push_back on vector..
|
|
if (Token::Match(tok2, "%varid% . push_front|push_back|insert|reserve|resize|clear", containerTok->varId())) {
|
|
invalidPointer = true;
|
|
function = tok2->tokAt(2);
|
|
}
|
|
|
|
// Using invalid pointer..
|
|
if (invalidPointer && tok2->varId() == pointerId) {
|
|
bool unknown = false;
|
|
if (CheckNullPointer::isPointerDeRef(tok2, unknown))
|
|
invalidPointerError(tok2, function->str(), tok2->str());
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// Iterator becomes invalid after reserve, resize, insert, push_back or push_front..
|
|
for (unsigned int iteratorId = 1; iteratorId < symbolDatabase->getVariableListSize(); iteratorId++) {
|
|
const Variable* var = symbolDatabase->getVariableFromVarId(iteratorId);
|
|
|
|
// Check that its an iterator
|
|
if (!var || !var->isLocal() || !Token::Match(var->typeEndToken(), "iterator|const_iterator|reverse_iterator|const_reverse_iterator"))
|
|
continue;
|
|
|
|
// ... on std::vector
|
|
if (!Token::Match(var->typeStartToken(), "std| ::| vector <"))
|
|
continue;
|
|
|
|
// the variable id for the vector
|
|
unsigned int vectorid = 0;
|
|
|
|
const Token* validatingToken = nullptr;
|
|
|
|
std::string invalidIterator;
|
|
const Token* end2 = var->scope()->classEnd;
|
|
for (const Token *tok2 = var->nameToken(); tok2 != end2; tok2 = tok2->next()) {
|
|
|
|
if (validatingToken == tok2) {
|
|
invalidIterator.clear();
|
|
validatingToken = nullptr;
|
|
}
|
|
|
|
// Using push_back or push_front inside a loop..
|
|
if (Token::simpleMatch(tok2, "for (")) {
|
|
tok2 = tok2->tokAt(2);
|
|
}
|
|
|
|
if (Token::Match(tok2, "%varid% = %var% . begin|rbegin|cbegin|crbegin ( ) ; %varid% != %var% . end|rend|cend|crend ( ) ; ++| %varid% ++| ) {", iteratorId)) {
|
|
// variable id for the loop iterator
|
|
const unsigned int varId(tok2->tokAt(2)->varId());
|
|
|
|
const Token *pushbackTok = nullptr;
|
|
|
|
// Count { and } for tok3
|
|
const Token *tok3 = tok2->tokAt(20);
|
|
for (const Token* const end3 = tok3->linkAt(-1); tok3 != end3; tok3 = tok3->next()) {
|
|
if (tok3->str() == "break" || tok3->str() == "return") {
|
|
pushbackTok = nullptr;
|
|
break;
|
|
} else if (Token::Match(tok3, "%varid% . push_front|push_back|insert|reserve|resize|clear|erase (", varId) && !tok3->previous()->isAssignmentOp()) {
|
|
if (tok3->strAt(2) != "erase" || (tok3->tokAt(4)->varId() != iteratorId && tok3->tokAt(5)->varId() != iteratorId)) // This case is handled in: CheckStl::iterators()
|
|
pushbackTok = tok3->tokAt(2);
|
|
}
|
|
}
|
|
|
|
if (pushbackTok)
|
|
invalidIteratorError(pushbackTok, pushbackTok->str(), tok2->str());
|
|
}
|
|
|
|
// Assigning iterator..
|
|
if (Token::Match(tok2, "%varid% =", iteratorId)) {
|
|
if (Token::Match(tok2->tokAt(2), "%var% . begin|end|rbegin|rend|cbegin|cend|crbegin|crend|insert|erase|find (")) {
|
|
if (!invalidIterator.empty() && Token::Match(tok2->tokAt(4), "insert|erase ( *| %varid% )|,", iteratorId)) {
|
|
invalidIteratorError(tok2, invalidIterator, var->name());
|
|
break;
|
|
}
|
|
vectorid = tok2->tokAt(2)->varId();
|
|
tok2 = tok2->linkAt(5);
|
|
} else {
|
|
vectorid = 0;
|
|
}
|
|
invalidIterator.clear();
|
|
}
|
|
|
|
// push_back on vector..
|
|
if (vectorid > 0 && Token::Match(tok2, "%varid% . push_front|push_back|insert|reserve|resize|clear|erase (", vectorid)) {
|
|
if (!invalidIterator.empty() && Token::Match(tok2->tokAt(2), "insert|erase ( *| %varid% ,|)", iteratorId)) {
|
|
invalidIteratorError(tok2, invalidIterator, var->name());
|
|
break;
|
|
}
|
|
|
|
if (tok2->strAt(2) != "erase" || (tok2->tokAt(4)->varId() != iteratorId && tok2->tokAt(5)->varId() != iteratorId)) // This case is handled in: CheckStl::iterators()
|
|
invalidIterator = tok2->strAt(2);
|
|
tok2 = tok2->linkAt(3);
|
|
}
|
|
|
|
else if (tok2->str() == "return" || tok2->str() == "throw")
|
|
validatingToken = Token::findsimplematch(tok2->next(), ";");
|
|
|
|
// TODO: instead of bail out for 'else' try to check all execution paths.
|
|
else if (tok2->str() == "break" || tok2->str() == "else")
|
|
invalidIterator.clear();
|
|
|
|
// Using invalid iterator..
|
|
if (!invalidIterator.empty()) {
|
|
if (Token::Match(tok2, "++|--|*|+|-|(|,|=|!= %varid%", iteratorId))
|
|
invalidIteratorError(tok2, invalidIterator, tok2->strAt(1));
|
|
if (Token::Match(tok2, "%varid% ++|--|+|-|.", iteratorId))
|
|
invalidIteratorError(tok2, invalidIterator, tok2->str());
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
// Error message for bad iterator usage..
|
|
void CheckStl::invalidIteratorError(const Token *tok, const std::string &func, const std::string &iterator_name)
|
|
{
|
|
reportError(tok, Severity::error, "invalidIterator2", "After " + func + "(), the iterator '" + iterator_name + "' may be invalid.", CWE664, false);
|
|
}
|
|
|
|
|
|
// Error message for bad iterator usage..
|
|
void CheckStl::invalidPointerError(const Token *tok, const std::string &func, const std::string &pointer_name)
|
|
{
|
|
reportError(tok, Severity::error, "invalidPointer", "Invalid pointer '" + pointer_name + "' after " + func + "().", CWE664, false);
|
|
}
|
|
|
|
|
|
void CheckStl::stlBoundaries()
|
|
{
|
|
const SymbolDatabase* const symbolDatabase = _tokenizer->getSymbolDatabase();
|
|
for (unsigned int iteratorId = 1; iteratorId < symbolDatabase->getVariableListSize(); iteratorId++) {
|
|
const Variable* var = symbolDatabase->getVariableFromVarId(iteratorId);
|
|
if (!var || !var->scope() || !var->scope()->isExecutable())
|
|
continue;
|
|
|
|
const Library::Container* container = _settings->library.detectContainer(var->typeStartToken(), true);
|
|
if (!container || container->opLessAllowed)
|
|
continue;
|
|
|
|
const Token* const end = var->scope()->classEnd;
|
|
for (const Token *tok = var->nameToken(); tok != end; tok = tok->next()) {
|
|
if (Token::Match(tok, "!!* %varid% <", var->declarationId())) {
|
|
stlBoundariesError(tok);
|
|
} else if (Token::Match(tok, "> %varid% !!.", var->declarationId())) {
|
|
stlBoundariesError(tok);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// Error message for bad boundary usage..
|
|
void CheckStl::stlBoundariesError(const Token *tok)
|
|
{
|
|
reportError(tok, Severity::error, "stlBoundaries",
|
|
"Dangerous comparison using operator< on iterator.\n"
|
|
"Iterator compared with operator<. This is dangerous since the order of items in the "
|
|
"container is not guaranteed. One should use operator!= instead to compare iterators.", CWE664, false);
|
|
}
|
|
|
|
static bool if_findCompare(const Token * const tokBack)
|
|
{
|
|
const Token *tok = tokBack->astParent();
|
|
if (!tok)
|
|
return true;
|
|
if (tok->isComparisonOp())
|
|
return (!tok->astOperand1()->isNumber() && !tok->astOperand2()->isNumber());
|
|
if (tok->isArithmeticalOp()) // result is used in some calculation
|
|
return true; // TODO: check if there is a comparison of the result somewhere
|
|
if (tok->str() == ".")
|
|
return true; // Dereferencing is OK, the programmer might know that the element exists - TODO: An inconclusive warning might be appropriate
|
|
if (tok->isAssignmentOp())
|
|
return if_findCompare(tok); // Go one step upwards in the AST
|
|
return false;
|
|
}
|
|
|
|
void CheckStl::if_find()
|
|
{
|
|
const bool printWarning = _settings->isEnabled(Settings::WARNING);
|
|
const bool printPerformance = _settings->isEnabled(Settings::PERFORMANCE);
|
|
if (!printWarning && !printPerformance)
|
|
return;
|
|
|
|
const SymbolDatabase *symbolDatabase = _tokenizer->getSymbolDatabase();
|
|
|
|
for (std::list<Scope>::const_iterator i = symbolDatabase->scopeList.begin(); i != symbolDatabase->scopeList.end(); ++i) {
|
|
if ((i->type != Scope::eIf && i->type != Scope::eWhile) || !i->classDef)
|
|
continue;
|
|
|
|
for (const Token *tok = i->classDef->next(); tok->str() != "{"; tok = tok->next()) {
|
|
const Token* funcTok = nullptr;
|
|
const Library::Container* container = nullptr;
|
|
|
|
if (Token::Match(tok, "%name% ("))
|
|
tok = tok->linkAt(1);
|
|
|
|
else if (tok->variable() && Token::Match(tok, "%var% . %name% (")) {
|
|
container = _settings->library.detectContainer(tok->variable()->typeStartToken());
|
|
funcTok = tok->tokAt(2);
|
|
}
|
|
|
|
// check also for vector-like or pointer containers
|
|
else if (tok->variable() && tok->astParent() && (tok->astParent()->str() == "*" || tok->astParent()->str() == "[")) {
|
|
const Token *tok2 = tok->astParent();
|
|
|
|
if (!Token::Match(tok2->astParent(), ". %name% ("))
|
|
continue;
|
|
|
|
funcTok = tok2->astParent()->next();
|
|
|
|
if (tok->variable()->isArrayOrPointer())
|
|
container = _settings->library.detectContainer(tok->variable()->typeStartToken());
|
|
else { // Container of container - find the inner container
|
|
container = _settings->library.detectContainer(tok->variable()->typeStartToken()); // outer container
|
|
tok2 = Token::findsimplematch(tok->variable()->typeStartToken(), "<", tok->variable()->typeEndToken());
|
|
if (container && container->type_templateArgNo >= 0 && tok2) {
|
|
tok2 = tok2->next();
|
|
for (int j = 0; j < container->type_templateArgNo; j++)
|
|
tok2 = tok2->nextTemplateArgument();
|
|
|
|
container = _settings->library.detectContainer(tok2); // innner container
|
|
} else
|
|
container = nullptr;
|
|
}
|
|
}
|
|
|
|
if (container && container->getAction(funcTok->str()) == Library::Container::FIND) {
|
|
if (if_findCompare(funcTok->next()))
|
|
continue;
|
|
|
|
if (printWarning && container->getYield(funcTok->str()) == Library::Container::ITERATOR)
|
|
if_findError(tok, false);
|
|
else if (printPerformance && container->stdStringLike && funcTok->str() == "find")
|
|
if_findError(tok, true);
|
|
} else if (printWarning && Token::Match(tok, "std :: find|find_if (")) {
|
|
// check that result is checked properly
|
|
if (!if_findCompare(tok->tokAt(3))) {
|
|
if_findError(tok, false);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
void CheckStl::if_findError(const Token *tok, bool str)
|
|
{
|
|
if (str)
|
|
reportError(tok, Severity::performance, "stlIfStrFind",
|
|
"Inefficient usage of string::find() in condition; string::compare() would be faster.\n"
|
|
"Either inefficient or wrong usage of string::find(). string::compare() will be faster if "
|
|
"string::find's result is compared with 0, because it will not scan the whole "
|
|
"string. If your intention is to check that there are no findings in the string, "
|
|
"you should compare with std::string::npos.", CWE597, false);
|
|
else
|
|
reportError(tok, Severity::warning, "stlIfFind", "Suspicious condition. The result of find() is an iterator, but it is not properly checked.", CWE398, false);
|
|
}
|
|
|
|
|
|
/**
|
|
* Is container.size() slow?
|
|
*/
|
|
static bool isCpp03ContainerSizeSlow(const Token *tok)
|
|
{
|
|
if (!tok)
|
|
return false;
|
|
const Variable* var = tok->variable();
|
|
return var && var->isStlType("list");
|
|
}
|
|
|
|
void CheckStl::size()
|
|
{
|
|
if (!_settings->isEnabled(Settings::PERFORMANCE))
|
|
return;
|
|
|
|
if (_settings->standards.cpp == Standards::CPP11)
|
|
return;
|
|
|
|
const SymbolDatabase* const symbolDatabase = _tokenizer->getSymbolDatabase();
|
|
const std::size_t functions = symbolDatabase->functionScopes.size();
|
|
for (std::size_t i = 0; i < functions; ++i) {
|
|
const Scope * scope = symbolDatabase->functionScopes[i];
|
|
for (const Token* tok = scope->classStart->next(); tok != scope->classEnd; tok = tok->next()) {
|
|
if (Token::Match(tok, "%var% . size ( )") ||
|
|
Token::Match(tok, "%name% . %var% . size ( )")) {
|
|
// get the variable
|
|
const Token *varTok = tok;
|
|
if (tok->strAt(2) != "size")
|
|
varTok = varTok->tokAt(2);
|
|
|
|
const Token* const end = varTok->tokAt(5);
|
|
|
|
// check for comparison to zero
|
|
if ((tok->previous() && !tok->previous()->isArithmeticalOp() && Token::Match(end, "==|<=|!=|> 0")) ||
|
|
(end->next() && !end->next()->isArithmeticalOp() && Token::Match(tok->tokAt(-2), "0 ==|>=|!=|<"))) {
|
|
if (isCpp03ContainerSizeSlow(varTok)) {
|
|
sizeError(varTok);
|
|
continue;
|
|
}
|
|
}
|
|
|
|
// check for comparison to one
|
|
if ((tok->previous() && !tok->previous()->isArithmeticalOp() && Token::Match(end, ">=|< 1") && !end->tokAt(2)->isArithmeticalOp()) ||
|
|
(end->next() && !end->next()->isArithmeticalOp() && Token::Match(tok->tokAt(-2), "1 <=|>") && !tok->tokAt(-3)->isArithmeticalOp())) {
|
|
if (isCpp03ContainerSizeSlow(varTok))
|
|
sizeError(varTok);
|
|
}
|
|
|
|
// check for using as boolean expression
|
|
else if ((Token::Match(tok->tokAt(-2), "if|while (") && end->str() == ")") ||
|
|
(tok->previous()->tokType() == Token::eLogicalOp && Token::Match(end, "&&|)|,|;|%oror%"))) {
|
|
if (isCpp03ContainerSizeSlow(varTok))
|
|
sizeError(varTok);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
void CheckStl::sizeError(const Token *tok)
|
|
{
|
|
const std::string varname = tok ? tok->str() : std::string("list");
|
|
reportError(tok, Severity::performance, "stlSize",
|
|
"Possible inefficient checking for '" + varname + "' emptiness.\n"
|
|
"Checking for '" + varname + "' emptiness might be inefficient. "
|
|
"Using " + varname + ".empty() instead of " + varname + ".size() can be faster. " +
|
|
varname + ".size() can take linear time but " + varname + ".empty() is "
|
|
"guaranteed to take constant time.", CWE398, false);
|
|
}
|
|
|
|
void CheckStl::redundantCondition()
|
|
{
|
|
if (!_settings->isEnabled(Settings::STYLE))
|
|
return;
|
|
|
|
const SymbolDatabase *symbolDatabase = _tokenizer->getSymbolDatabase();
|
|
|
|
for (std::list<Scope>::const_iterator i = symbolDatabase->scopeList.begin(); i != symbolDatabase->scopeList.end(); ++i) {
|
|
if (i->type != Scope::eIf)
|
|
continue;
|
|
|
|
const Token* tok = i->classDef->tokAt(2);
|
|
if (!Token::Match(tok, "%name% . find ( %any% ) != %name% . end|rend|cend|crend ( ) ) { %name% . remove|erase ( %any% ) ;"))
|
|
continue;
|
|
|
|
// Get tokens for the fields %name% and %any%
|
|
const Token *var1 = tok;
|
|
const Token *any1 = var1->tokAt(4);
|
|
const Token *var2 = any1->tokAt(3);
|
|
const Token *var3 = var2->tokAt(7);
|
|
const Token *any2 = var3->tokAt(4);
|
|
|
|
// Check if all the "%name%" fields are the same and if all the "%any%" are the same..
|
|
if (var1->str() == var2->str() &&
|
|
var2->str() == var3->str() &&
|
|
any1->str() == any2->str()) {
|
|
redundantIfRemoveError(tok);
|
|
}
|
|
}
|
|
}
|
|
|
|
void CheckStl::redundantIfRemoveError(const Token *tok)
|
|
{
|
|
reportError(tok, Severity::style, "redundantIfRemove",
|
|
"Redundant checking of STL container element existence before removing it.\n"
|
|
"Redundant checking of STL container element existence before removing it. "
|
|
"It is safe to call the remove method on a non-existing element.", CWE398, false);
|
|
}
|
|
|
|
void CheckStl::missingComparison()
|
|
{
|
|
if (!_settings->isEnabled(Settings::WARNING))
|
|
return;
|
|
|
|
const SymbolDatabase* const symbolDatabase = _tokenizer->getSymbolDatabase();
|
|
|
|
for (std::list<Scope>::const_iterator i = symbolDatabase->scopeList.begin(); i != symbolDatabase->scopeList.end(); ++i) {
|
|
if (i->type != Scope::eFor || !i->classDef)
|
|
continue;
|
|
|
|
for (const Token *tok2 = i->classDef->tokAt(2); tok2 != i->classStart; tok2 = tok2->next()) {
|
|
if (tok2->str() == ";")
|
|
break;
|
|
|
|
if (!Token::Match(tok2, "%var% = %name% . begin|rbegin|cbegin|crbegin ( ) ; %name% != %name% . end|rend|cend|crend ( ) ; ++| %name% ++| ) {"))
|
|
continue;
|
|
|
|
// same container
|
|
if (tok2->strAt(2) != tok2->strAt(10))
|
|
break;
|
|
|
|
const unsigned int iteratorId(tok2->varId());
|
|
|
|
// same iterator
|
|
if (iteratorId == tok2->tokAt(10)->varId())
|
|
break;
|
|
|
|
// increment iterator
|
|
if (!Token::Match(tok2->tokAt(16), "++ %varid% )", iteratorId) &&
|
|
!Token::Match(tok2->tokAt(16), "%varid% ++ )", iteratorId)) {
|
|
break;
|
|
}
|
|
|
|
const Token *incrementToken = nullptr;
|
|
|
|
// Parse loop..
|
|
for (const Token *tok3 = i->classStart; tok3 != i->classEnd; tok3 = tok3->next()) {
|
|
if (Token::Match(tok3, "%varid% ++", iteratorId))
|
|
incrementToken = tok3;
|
|
else if (Token::Match(tok3->previous(), "++ %varid% !!.", iteratorId))
|
|
incrementToken = tok3;
|
|
else if (Token::Match(tok3, "%varid% !=|==", iteratorId))
|
|
incrementToken = nullptr;
|
|
else if (tok3->str() == "break" || tok3->str() == "return")
|
|
incrementToken = nullptr;
|
|
else if (Token::Match(tok3, "%varid% = %name% . insert ( ++| %varid% ++| ,", iteratorId)) {
|
|
// skip insertion..
|
|
tok3 = tok3->linkAt(6);
|
|
if (!tok3)
|
|
break;
|
|
}
|
|
}
|
|
if (incrementToken)
|
|
missingComparisonError(incrementToken, tok2->tokAt(16));
|
|
}
|
|
}
|
|
}
|
|
|
|
void CheckStl::missingComparisonError(const Token *incrementToken1, const Token *incrementToken2)
|
|
{
|
|
std::list<const Token*> callstack;
|
|
callstack.push_back(incrementToken1);
|
|
callstack.push_back(incrementToken2);
|
|
|
|
std::ostringstream errmsg;
|
|
errmsg << "Missing bounds check for extra iterator increment in loop.\n"
|
|
<< "The iterator incrementing is suspicious - it is incremented at line ";
|
|
if (incrementToken1)
|
|
errmsg << incrementToken1->linenr();
|
|
errmsg << " and then at line ";
|
|
if (incrementToken2)
|
|
errmsg << incrementToken2->linenr();
|
|
errmsg << ". The loop might unintentionally skip an element in the container. "
|
|
<< "There is no comparison between these increments to prevent that the iterator is "
|
|
<< "incremented beyond the end.";
|
|
|
|
reportError(callstack, Severity::warning, "StlMissingComparison", errmsg.str(), CWE834, false);
|
|
}
|
|
|
|
|
|
static bool isLocal(const Token *tok)
|
|
{
|
|
const Variable *var = tok->variable();
|
|
return var && !var->isStatic() && var->isLocal();
|
|
}
|
|
|
|
namespace {
|
|
const std::set<std::string> stl_string_stream = make_container< std::set<std::string> >() <<
|
|
"istringstream" << "ostringstream" << "stringstream" << "wstringstream" ;
|
|
}
|
|
|
|
void CheckStl::string_c_str()
|
|
{
|
|
const bool printInconclusive = _settings->inconclusive;
|
|
const bool printPerformance = _settings->isEnabled(Settings::PERFORMANCE);
|
|
|
|
const SymbolDatabase* symbolDatabase = _tokenizer->getSymbolDatabase();
|
|
|
|
// Find all functions that take std::string as argument
|
|
std::multimap<std::string, unsigned int> c_strFuncParam;
|
|
if (printPerformance) {
|
|
for (std::list<Scope>::const_iterator scope = symbolDatabase->scopeList.begin(); scope != symbolDatabase->scopeList.end(); ++scope) {
|
|
for (std::list<Function>::const_iterator func = scope->functionList.begin(); func != scope->functionList.end(); ++func) {
|
|
if (c_strFuncParam.erase(func->tokenDef->str()) != 0) { // Check if function with this name was already found
|
|
c_strFuncParam.insert(std::make_pair(func->tokenDef->str(), 0)); // Disable, because there are overloads. TODO: Handle overloads
|
|
continue;
|
|
}
|
|
|
|
unsigned int numpar = 0;
|
|
c_strFuncParam.insert(std::make_pair(func->tokenDef->str(), numpar)); // Insert function as dummy, to indicate that there is at least one function with that name
|
|
for (std::list<Variable>::const_iterator var = func->argumentList.cbegin(); var != func->argumentList.cend(); ++var) {
|
|
numpar++;
|
|
if (var->isStlStringType() && (!var->isReference() || var->isConst()))
|
|
c_strFuncParam.insert(std::make_pair(func->tokenDef->str(), numpar));
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// Try to detect common problems when using string::c_str()
|
|
for (std::list<Scope>::const_iterator scope = symbolDatabase->scopeList.begin(); scope != symbolDatabase->scopeList.end(); ++scope) {
|
|
if (scope->type != Scope::eFunction || !scope->function)
|
|
continue;
|
|
|
|
enum {charPtr, stdString, stdStringConstRef, Other} returnType = Other;
|
|
if (Token::Match(scope->function->tokenDef->tokAt(-2), "char|wchar_t *"))
|
|
returnType = charPtr;
|
|
else if (Token::Match(scope->function->tokenDef->tokAt(-5), "const std :: string|wstring &"))
|
|
returnType = stdStringConstRef;
|
|
else if (Token::Match(scope->function->tokenDef->tokAt(-3), "std :: string|wstring !!&"))
|
|
returnType = stdString;
|
|
|
|
for (const Token *tok = scope->classStart; tok && tok != scope->classEnd; tok = tok->next()) {
|
|
// Invalid usage..
|
|
if (Token::Match(tok, "throw %var% . c_str|data ( ) ;") && isLocal(tok->next()) &&
|
|
tok->next()->variable() && tok->next()->variable()->isStlStringType()) {
|
|
string_c_strThrowError(tok);
|
|
} else if (Token::Match(tok, "[;{}] %name% = %var% . str ( ) . c_str|data ( ) ;")) {
|
|
const Variable* var = tok->next()->variable();
|
|
const Variable* var2 = tok->tokAt(3)->variable();
|
|
if (var && var->isPointer() && var2 && var2->isStlType(stl_string_stream))
|
|
string_c_strError(tok);
|
|
} else if (Token::Match(tok, "[;{}] %var% = %name% (") &&
|
|
Token::Match(tok->linkAt(4), ") . c_str|data ( ) ;") &&
|
|
tok->tokAt(3)->function() && Token::Match(tok->tokAt(3)->function()->retDef, "std :: string|wstring %name%")) {
|
|
const Variable* var = tok->next()->variable();
|
|
if (var && var->isPointer())
|
|
string_c_strError(tok);
|
|
} else if (printPerformance && Token::Match(tok, "%name% ( !!)") && c_strFuncParam.find(tok->str()) != c_strFuncParam.end() &&
|
|
!Token::Match(tok->previous(), "::|.") && tok->varId() == 0 && tok->str() != scope->className) { // calling function. TODO: Add support for member functions
|
|
const std::pair<std::multimap<std::string, unsigned int>::const_iterator, std::multimap<std::string, unsigned int>::const_iterator> range = c_strFuncParam.equal_range(tok->str());
|
|
for (std::multimap<std::string, unsigned int>::const_iterator i = range.first; i != range.second; ++i) {
|
|
if (i->second == 0)
|
|
continue;
|
|
|
|
const Token* tok2 = tok->tokAt(2);
|
|
unsigned int j;
|
|
for (j = 0; tok2 && j < i->second-1; j++)
|
|
tok2 = tok2->nextArgument();
|
|
if (tok2)
|
|
tok2 = tok2->nextArgument();
|
|
else
|
|
break;
|
|
if (!tok2 && j == i->second-1)
|
|
tok2 = tok->next()->link();
|
|
else if (tok2)
|
|
tok2 = tok2->previous();
|
|
else
|
|
break;
|
|
if (tok2 && Token::Match(tok2->tokAt(-4), ". c_str|data ( )")) {
|
|
const Variable* var = tok2->tokAt(-5)->variable();
|
|
if (var && var->isStlStringType()) {
|
|
string_c_strParam(tok, i->second);
|
|
} else if (Token::Match(tok2->tokAt(-9), "%name% . str ( )")) { // Check ss.str().c_str() as parameter
|
|
const Variable* ssVar = tok2->tokAt(-9)->variable();
|
|
if (ssVar && ssVar->isStlType(stl_string_stream))
|
|
string_c_strParam(tok, i->second);
|
|
}
|
|
|
|
}
|
|
}
|
|
}
|
|
|
|
// Using c_str() to get the return value is only dangerous if the function returns a char*
|
|
if ((returnType == charPtr || (printPerformance && (returnType == stdString || returnType == stdStringConstRef))) && tok->str() == "return") {
|
|
bool err = false;
|
|
|
|
const Token* tok2 = tok->next();
|
|
if (Token::Match(tok2, "std :: string|wstring (") &&
|
|
Token::Match(tok2->linkAt(3), ") . c_str|data ( ) ;")) {
|
|
err = true;
|
|
} else if (Token::simpleMatch(tok2, "(") &&
|
|
Token::Match(tok2->link(), ") . c_str|data ( ) ;")) {
|
|
// Check for "+ localvar" or "+ std::string(" inside the bracket
|
|
bool is_implicit_std_string = printInconclusive;
|
|
const Token *search_end = tok2->link();
|
|
for (const Token *search_tok = tok2->next(); search_tok != search_end; search_tok = search_tok->next()) {
|
|
if (Token::Match(search_tok, "+ %var%") && isLocal(search_tok->next()) &&
|
|
search_tok->next()->variable() && search_tok->next()->variable()->isStlStringType()) {
|
|
is_implicit_std_string = true;
|
|
break;
|
|
} else if (Token::Match(search_tok, "+ std :: string|wstring (")) {
|
|
is_implicit_std_string = true;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (is_implicit_std_string)
|
|
err = true;
|
|
}
|
|
|
|
bool local = false;
|
|
bool ptrOrRef = false;
|
|
const Variable* lastVar = nullptr;
|
|
const Function* lastFunc = nullptr;
|
|
bool funcStr = false;
|
|
if (Token::Match(tok2, "%var% .")) {
|
|
local = isLocal(tok2);
|
|
bool refToNonLocal = false;
|
|
if (tok2->variable() && tok2->variable()->isReference()) {
|
|
const Token *refTok = tok2->variable()->nameToken();
|
|
refToNonLocal = true; // safe assumption is default to avoid FPs
|
|
if (Token::Match(refTok, "%var% = %var% .|;|["))
|
|
refToNonLocal = !isLocal(refTok->tokAt(2));
|
|
}
|
|
ptrOrRef = refToNonLocal || (tok2->variable() && tok2->variable()->isPointer());
|
|
}
|
|
while (tok2) {
|
|
if (Token::Match(tok2, "%var% .|::")) {
|
|
if (ptrOrRef)
|
|
local = false;
|
|
lastVar = tok2->variable();
|
|
tok2 = tok2->tokAt(2);
|
|
} else if (Token::Match(tok2, "%name% (") && Token::simpleMatch(tok2->linkAt(1), ") .")) {
|
|
lastFunc = tok2->function();
|
|
local = false;
|
|
funcStr = tok2->str() == "str";
|
|
tok2 = tok2->linkAt(1)->tokAt(2);
|
|
} else
|
|
break;
|
|
}
|
|
|
|
if (Token::Match(tok2, "c_str|data ( ) ;")) {
|
|
if ((local || returnType != charPtr) && lastVar && lastVar->isStlStringType())
|
|
err = true;
|
|
else if (funcStr && lastVar && lastVar->isStlType(stl_string_stream))
|
|
err = true;
|
|
else if (lastFunc && Token::Match(lastFunc->tokenDef->tokAt(-3), "std :: string|wstring"))
|
|
err = true;
|
|
}
|
|
|
|
if (err) {
|
|
if (returnType == charPtr)
|
|
string_c_strError(tok);
|
|
else
|
|
string_c_strReturn(tok);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
void CheckStl::string_c_strThrowError(const Token* tok)
|
|
{
|
|
reportError(tok, Severity::error, "stlcstrthrow", "Dangerous usage of c_str(). The value returned by c_str() is invalid after throwing exception.\n"
|
|
"Dangerous usage of c_str(). The string is destroyed after the c_str() call so the thrown pointer is invalid.");
|
|
}
|
|
|
|
void CheckStl::string_c_strError(const Token* tok)
|
|
{
|
|
reportError(tok, Severity::error, "stlcstr", "Dangerous usage of c_str(). The value returned by c_str() is invalid after this call.\n"
|
|
"Dangerous usage of c_str(). The c_str() return value is only valid until its string is deleted.", CWE664, false);
|
|
}
|
|
|
|
void CheckStl::string_c_strReturn(const Token* tok)
|
|
{
|
|
reportError(tok, Severity::performance, "stlcstrReturn", "Returning the result of c_str() in a function that returns std::string is slow and redundant.\n"
|
|
"The conversion from const char* as returned by c_str() to std::string creates an unnecessary string copy. Solve that by directly returning the string.", CWE704, false);
|
|
}
|
|
|
|
void CheckStl::string_c_strParam(const Token* tok, unsigned int number)
|
|
{
|
|
std::ostringstream oss;
|
|
oss << "Passing the result of c_str() to a function that takes std::string as argument no. " << number << " is slow and redundant.\n"
|
|
"The conversion from const char* as returned by c_str() to std::string creates an unnecessary string copy. Solve that by directly passing the string.";
|
|
reportError(tok, Severity::performance, "stlcstrParam", oss.str(), CWE704, false);
|
|
}
|
|
|
|
static bool hasArrayEnd(const Token *tok1)
|
|
{
|
|
const Token *end = Token::findsimplematch(tok1, ";");
|
|
return (end && Token::simpleMatch(end->previous(), "] ;"));
|
|
}
|
|
|
|
static bool hasArrayEndParen(const Token *tok1)
|
|
{
|
|
const Token *end = Token::findsimplematch(tok1, ";");
|
|
return (end && end->previous() &&
|
|
Token::simpleMatch(end->tokAt(-2), "] ) ;"));
|
|
}
|
|
|
|
//---------------------------------------------------------------------------
|
|
//
|
|
//---------------------------------------------------------------------------
|
|
void CheckStl::checkAutoPointer()
|
|
{
|
|
std::set<unsigned int> autoPtrVarId;
|
|
std::map<unsigned int, const std::string> mallocVarId; // variables allocated by the malloc-like function
|
|
const char STL_CONTAINER_LIST[] = "array|bitset|deque|list|forward_list|map|multimap|multiset|priority_queue|queue|set|stack|vector|hash_map|hash_multimap|hash_set|unordered_map|unordered_multimap|unordered_set|unordered_multiset|basic_string";
|
|
const int malloc = _settings->library.allocId("malloc"); // allocation function, which are not compatible with auto_ptr
|
|
const bool printStyle = _settings->isEnabled(Settings::STYLE);
|
|
|
|
for (const Token *tok = _tokenizer->tokens(); tok; tok = tok->next()) {
|
|
if (Token::simpleMatch(tok, "auto_ptr <")) {
|
|
if ((tok->strAt(-1) == "<" && Token::Match(tok->tokAt(-2), STL_CONTAINER_LIST)) ||
|
|
(Token::simpleMatch(tok->tokAt(-3), "< std :: auto_ptr") && Token::Match(tok->tokAt(-4), STL_CONTAINER_LIST))) {
|
|
autoPointerContainerError(tok);
|
|
} else {
|
|
const Token *tok2 = tok->linkAt(1);
|
|
|
|
if (Token::Match(tok2, "> %name%")) {
|
|
const Token *tok3 = tok2->tokAt(2);
|
|
if (Token::Match(tok3, "( new %type%") && hasArrayEndParen(tok3)) {
|
|
autoPointerArrayError(tok2->next());
|
|
}
|
|
if (Token::Match(tok3, "( %name% (") && malloc && _settings->library.alloc(tok3->next(), -1) == malloc) {
|
|
// malloc-like function allocated memory passed to the auto_ptr constructor -> error
|
|
autoPointerMallocError(tok2->next(), tok3->next()->str());
|
|
}
|
|
if (Token::Match(tok3, "( %var%")) {
|
|
const std::map<unsigned int, const std::string>::const_iterator it = mallocVarId.find(tok3->next()->varId());
|
|
if (it != mallocVarId.cend()) {
|
|
// pointer on the memory allocated by malloc used in the auto pointer constructor -> error
|
|
autoPointerMallocError(tok2->next(), it->second);
|
|
}
|
|
}
|
|
while (tok3 && tok3->str() != ";") {
|
|
tok3 = tok3->next();
|
|
}
|
|
if (tok3) {
|
|
tok3 = tok3->tokAt(-2);
|
|
if (Token::simpleMatch(tok3->previous(), "[ ] )")) {
|
|
autoPointerArrayError(tok2->next());
|
|
} else if (tok3->varId()) {
|
|
const Token *decltok = Token::findmatch(_tokenizer->tokens(), "%varid% = new %type%", tok3->varId());
|
|
if (decltok && hasArrayEnd(decltok)) {
|
|
autoPointerArrayError(tok2->next());
|
|
}
|
|
}
|
|
if (tok2->next()->varId()) {
|
|
autoPtrVarId.insert(tok2->next()->varId());
|
|
}
|
|
}
|
|
}
|
|
}
|
|
} else {
|
|
if (Token::Match(tok, "%name% = %var% ;")) {
|
|
if (printStyle) {
|
|
const std::set<unsigned int>::const_iterator iter = autoPtrVarId.find(tok->tokAt(2)->varId());
|
|
if (iter != autoPtrVarId.end()) {
|
|
autoPointerError(tok->tokAt(2));
|
|
}
|
|
}
|
|
} else if ((Token::Match(tok, "%var% = new %type%") && hasArrayEnd(tok)) ||
|
|
(Token::Match(tok, "%var% . reset ( new %type%") && hasArrayEndParen(tok))) {
|
|
const std::set<unsigned int>::const_iterator iter = autoPtrVarId.find(tok->varId());
|
|
if (iter != autoPtrVarId.end()) {
|
|
autoPointerArrayError(tok);
|
|
}
|
|
} else if (Token::Match(tok, "%var% = %name% (") && malloc && _settings->library.alloc(tok->tokAt(2), -1) == malloc) {
|
|
// C library function like 'malloc' used together with auto pointer -> error
|
|
const std::set<unsigned int>::const_iterator iter = autoPtrVarId.find(tok->varId());
|
|
if (iter != autoPtrVarId.end()) {
|
|
autoPointerMallocError(tok, tok->strAt(2));
|
|
} else if (tok->varId()) {
|
|
// it is not an auto pointer variable and it is allocated by malloc like function.
|
|
mallocVarId.insert(std::make_pair(tok->varId(), tok->strAt(2)));
|
|
}
|
|
} else if (Token::Match(tok, "%var% . reset ( %name% (") && malloc && _settings->library.alloc(tok->tokAt(4), -1) == malloc) {
|
|
// C library function like 'malloc' used when resetting auto pointer -> error
|
|
const std::set<unsigned int>::const_iterator iter = autoPtrVarId.find(tok->varId());
|
|
if (iter != autoPtrVarId.end()) {
|
|
autoPointerMallocError(tok, tok->strAt(4));
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
void CheckStl::autoPointerError(const Token *tok)
|
|
{
|
|
reportError(tok, Severity::style, "useAutoPointerCopy",
|
|
"Copying 'auto_ptr' pointer to another does not create two equal objects since one has lost its ownership of the pointer.\n"
|
|
"'std::auto_ptr' has semantics of strict ownership, meaning that the 'auto_ptr' instance is the sole entity responsible for the object's lifetime. If an 'auto_ptr' is copied, the source looses the reference.",
|
|
CWE398, false);
|
|
}
|
|
|
|
void CheckStl::autoPointerContainerError(const Token *tok)
|
|
{
|
|
reportError(tok, Severity::error, "useAutoPointerContainer",
|
|
"You can randomly lose access to pointers if you store 'auto_ptr' pointers in an STL container.\n"
|
|
"An element of container must be able to be copied but 'auto_ptr' does not fulfill this requirement. You should consider to use 'shared_ptr' or 'unique_ptr'. It is suitable for use in containers, because they no longer copy their values, they move them.", CWE664, false
|
|
);
|
|
}
|
|
|
|
void CheckStl::autoPointerArrayError(const Token *tok)
|
|
{
|
|
reportError(tok, Severity::error, "useAutoPointerArray",
|
|
"Object pointed by an 'auto_ptr' is destroyed using operator 'delete'. You should not use 'auto_ptr' for pointers obtained with operator 'new[]'.\n"
|
|
"Object pointed by an 'auto_ptr' is destroyed using operator 'delete'. This means that you should only use 'auto_ptr' for pointers obtained with operator 'new'. This excludes arrays, which are allocated by operator 'new[]' and must be deallocated by operator 'delete[]'.", CWE664, false
|
|
);
|
|
}
|
|
|
|
void CheckStl::autoPointerMallocError(const Token *tok, const std::string& allocFunction)
|
|
{
|
|
const std::string summary = "Object pointed by an 'auto_ptr' is destroyed using operator 'delete'. You should not use 'auto_ptr' for pointers obtained with function '" + allocFunction + "'.";
|
|
const std::string verbose = summary + " This means that you should only use 'auto_ptr' for pointers obtained with operator 'new'. This excludes use C library allocation functions (for example '" + allocFunction + "'), which must be deallocated by the appropriate C library function.";
|
|
reportError(tok, Severity::error, "useAutoPointerMalloc", summary + "\n" + verbose, CWE762, false);
|
|
}
|
|
|
|
namespace {
|
|
const std::set<std::string> stl_containers_with_empty_and_clear = make_container< std::set<std::string> >() <<
|
|
"deque" << "forward_list" << "list" <<
|
|
"map" << "multimap" << "multiset" << "set" << "string" <<
|
|
"unordered_map" << "unordered_multimap" << "unordered_multiset" <<
|
|
"unordered_set" << "vector" << "wstring";
|
|
|
|
}
|
|
|
|
void CheckStl::uselessCalls()
|
|
{
|
|
const bool printPerformance = _settings->isEnabled(Settings::PERFORMANCE);
|
|
const bool printWarning = _settings->isEnabled(Settings::WARNING);
|
|
if (!printPerformance && !printWarning)
|
|
return;
|
|
|
|
|
|
const SymbolDatabase* symbolDatabase = _tokenizer->getSymbolDatabase();
|
|
const std::size_t functions = symbolDatabase->functionScopes.size();
|
|
for (std::size_t i = 0; i < functions; ++i) {
|
|
const Scope * scope = symbolDatabase->functionScopes[i];
|
|
for (const Token* tok = scope->classStart; tok != scope->classEnd; tok = tok->next()) {
|
|
if (printWarning && Token::Match(tok, "%var% . compare|find|rfind|find_first_not_of|find_first_of|find_last_not_of|find_last_of ( %name% [,)]") &&
|
|
tok->varId() == tok->tokAt(4)->varId()) {
|
|
const Variable* var = tok->variable();
|
|
if (!var || !var->isStlType())
|
|
continue;
|
|
uselessCallsReturnValueError(tok->tokAt(4), tok->str(), tok->strAt(2));
|
|
} else if (printPerformance && Token::Match(tok, "%var% . swap ( %name% )") &&
|
|
tok->varId() == tok->tokAt(4)->varId()) {
|
|
const Variable* var = tok->variable();
|
|
if (!var || !var->isStlType())
|
|
continue;
|
|
uselessCallsSwapError(tok, tok->str());
|
|
} else if (printPerformance && Token::Match(tok, "%var% . substr (") &&
|
|
tok->variable() && tok->variable()->isStlStringType()) {
|
|
if (Token::Match(tok->tokAt(4), "0| )")) {
|
|
uselessCallsSubstrError(tok, false);
|
|
} else if (tok->strAt(4) == "0" && tok->linkAt(3)->strAt(-1) == "npos") {
|
|
if (!tok->linkAt(3)->previous()->variable()) // Make sure that its no variable
|
|
uselessCallsSubstrError(tok, false);
|
|
} else if (Token::simpleMatch(tok->linkAt(3)->tokAt(-2), ", 0 )"))
|
|
uselessCallsSubstrError(tok, true);
|
|
} else if (printWarning && Token::Match(tok, "[{};] %var% . empty ( ) ;") &&
|
|
tok->next()->variable() && tok->next()->variable()->isStlType(stl_containers_with_empty_and_clear))
|
|
uselessCallsEmptyError(tok->next());
|
|
else if (Token::Match(tok, "[{};] std :: remove|remove_if|unique (") && tok->tokAt(5)->nextArgument())
|
|
uselessCallsRemoveError(tok->next(), tok->strAt(3));
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
void CheckStl::uselessCallsReturnValueError(const Token *tok, const std::string &varname, const std::string &function)
|
|
{
|
|
std::ostringstream errmsg;
|
|
errmsg << "It is inefficient to call '" << varname << "." << function << "(" << varname << ")' as it always returns 0.\n"
|
|
<< "'std::string::" << function << "()' returns zero when given itself as parameter "
|
|
<< "(" << varname << "." << function << "(" << varname << ")). As it is currently the "
|
|
<< "code is inefficient. It is possible either the string searched ('"
|
|
<< varname << "') or searched for ('" << varname << "') is wrong.";
|
|
reportError(tok, Severity::warning, "uselessCallsCompare", errmsg.str(), CWE628, false);
|
|
}
|
|
|
|
void CheckStl::uselessCallsSwapError(const Token *tok, const std::string &varname)
|
|
{
|
|
std::ostringstream errmsg;
|
|
errmsg << "It is inefficient to swap a object with itself by calling '" << varname << ".swap(" << varname << ")'\n"
|
|
<< "The 'swap()' function has no logical effect when given itself as parameter "
|
|
<< "(" << varname << ".swap(" << varname << ")). As it is currently the "
|
|
<< "code is inefficient. Is the object or the parameter wrong here?";
|
|
reportError(tok, Severity::performance, "uselessCallsSwap", errmsg.str(), CWE628, false);
|
|
}
|
|
|
|
void CheckStl::uselessCallsSubstrError(const Token *tok, bool empty)
|
|
{
|
|
if (empty)
|
|
reportError(tok, Severity::performance, "uselessCallsSubstr", "Ineffective call of function 'substr' because it returns an empty string.", CWE398, false);
|
|
else
|
|
reportError(tok, Severity::performance, "uselessCallsSubstr", "Ineffective call of function 'substr' because it returns a copy of the object. Use operator= instead.", CWE398, false);
|
|
}
|
|
|
|
void CheckStl::uselessCallsEmptyError(const Token *tok)
|
|
{
|
|
reportError(tok, Severity::warning, "uselessCallsEmpty", "Ineffective call of function 'empty()'. Did you intend to call 'clear()' instead?", CWE398, false);
|
|
}
|
|
|
|
void CheckStl::uselessCallsRemoveError(const Token *tok, const std::string& function)
|
|
{
|
|
reportError(tok, Severity::warning, "uselessCallsRemove", "Return value of std::" + function + "() ignored. Elements remain in container.\n"
|
|
"The return value of std::" + function + "() is ignored. This function returns an iterator to the end of the range containing those elements that should be kept. "
|
|
"Elements past new end remain valid but with unspecified values. Use the erase method of the container to delete them.", CWE762, false);
|
|
}
|
|
|
|
// Check for iterators being dereferenced before being checked for validity.
|
|
// E.g. if (*i && i != str.end()) { }
|
|
void CheckStl::checkDereferenceInvalidIterator()
|
|
{
|
|
if (!_settings->isEnabled(Settings::WARNING))
|
|
return;
|
|
|
|
// Iterate over "if", "while", and "for" conditions where there may
|
|
// be an iterator that is dereferenced before being checked for validity.
|
|
const std::list<Scope>& scopeList = _tokenizer->getSymbolDatabase()->scopeList;
|
|
for (std::list<Scope>::const_iterator i = scopeList.begin(); i != scopeList.end(); ++i) {
|
|
if (!(i->type == Scope::eIf || i->type == Scope::eDo || i->type == Scope::eWhile || i->type == Scope::eFor))
|
|
continue;
|
|
|
|
const Token* const tok = i->classDef;
|
|
const Token* startOfCondition = tok->next();
|
|
if (i->type == Scope::eDo)
|
|
startOfCondition = startOfCondition->link()->tokAt(2);
|
|
if (!startOfCondition) // ticket #6626 invalid code
|
|
continue;
|
|
const Token* endOfCondition = startOfCondition->link();
|
|
if (!endOfCondition)
|
|
continue;
|
|
|
|
// For "for" loops, only search between the two semicolons
|
|
if (i->type == Scope::eFor) {
|
|
startOfCondition = Token::findsimplematch(tok->tokAt(2), ";", endOfCondition);
|
|
if (!startOfCondition)
|
|
continue;
|
|
endOfCondition = Token::findsimplematch(startOfCondition->next(), ";", endOfCondition);
|
|
if (!endOfCondition)
|
|
continue;
|
|
}
|
|
|
|
// Only consider conditions composed of all "&&" terms and
|
|
// conditions composed of all "||" terms
|
|
const bool isOrExpression =
|
|
Token::findsimplematch(startOfCondition, "||", endOfCondition) != nullptr;
|
|
const bool isAndExpression =
|
|
Token::findsimplematch(startOfCondition, "&&", endOfCondition) != nullptr;
|
|
|
|
// Look for a check of the validity of an iterator
|
|
const Token* validityCheckTok = nullptr;
|
|
if (!isOrExpression && isAndExpression) {
|
|
validityCheckTok =
|
|
Token::findmatch(startOfCondition, "&& %var% != %name% . end|rend|cend|crend ( )", endOfCondition);
|
|
} else if (isOrExpression && !isAndExpression) {
|
|
validityCheckTok =
|
|
Token::findmatch(startOfCondition, "%oror% %var% == %name% . end|rend|cend|crend ( )", endOfCondition);
|
|
}
|
|
|
|
if (!validityCheckTok)
|
|
continue;
|
|
const unsigned int iteratorVarId = validityCheckTok->next()->varId();
|
|
|
|
// If the iterator dereference is to the left of the check for
|
|
// the iterator's validity, report an error.
|
|
const Token* const dereferenceTok =
|
|
Token::findmatch(startOfCondition, "* %varid%", validityCheckTok, iteratorVarId);
|
|
if (dereferenceTok)
|
|
dereferenceInvalidIteratorError(dereferenceTok, dereferenceTok->strAt(1));
|
|
}
|
|
}
|
|
|
|
void CheckStl::dereferenceInvalidIteratorError(const Token* deref, const std::string &iterName)
|
|
{
|
|
reportError(deref, Severity::warning,
|
|
"derefInvalidIterator", "Possible dereference of an invalid iterator: " + iterName + "\n" +
|
|
"Make sure to check that the iterator is valid before dereferencing it - not after.", CWE825, false);
|
|
}
|
|
|
|
|
|
|
|
void CheckStl::readingEmptyStlContainer_parseUsage(const Token* tok, const Library::Container* container, std::map<unsigned int, const Library::Container*>& empty, bool noerror)
|
|
{
|
|
// Check for various conditions for the way stl containers and variables can be used
|
|
if (tok->strAt(1) == "=" || (tok->strAt(1) == "[" && Token::simpleMatch(tok->linkAt(1), "] ="))) {
|
|
// Assignment (LHS)
|
|
empty.erase(tok->varId());
|
|
} else if (Token::Match(tok, "%name% [")) {
|
|
// Access through operator[]
|
|
if (!container->arrayLike_indexOp) { // operator[] inserts an element if used on a std::map
|
|
if (!noerror && tok->strAt(-1) == "=")
|
|
readingEmptyStlContainerError(tok);
|
|
empty.erase(tok->varId());
|
|
} else if (!noerror)
|
|
readingEmptyStlContainerError(tok);
|
|
} else if (Token::Match(tok, "%name% . %type% (")) {
|
|
// Member function call
|
|
const Library::Container::Action action = container->getAction(tok->strAt(2));
|
|
if ((action == Library::Container::FIND || action == Library::Container::ERASE || action == Library::Container::POP || action == Library::Container::CLEAR) && !noerror) {
|
|
readingEmptyStlContainerError(tok);
|
|
return;
|
|
}
|
|
|
|
const Token* parent = tok->tokAt(3)->astParent();
|
|
const Library::Container::Yield yield = container->getYield(tok->strAt(2));
|
|
const bool yieldsIterator = (yield == Library::Container::ITERATOR || yield == Library::Container::START_ITERATOR || yield == Library::Container::END_ITERATOR);
|
|
if (yield != Library::Container::NO_YIELD &&
|
|
(!parent || Token::Match(parent, "%cop%|*") || parent->isAssignmentOp() || !yieldsIterator)) { // These functions read from the container
|
|
if (!noerror && (!yieldsIterator || !parent || !parent->isAssignmentOp()))
|
|
readingEmptyStlContainerError(tok);
|
|
} else
|
|
empty.erase(tok->varId());
|
|
} else if (tok->strAt(-1) == "=") {
|
|
// Assignment (RHS)
|
|
if (!noerror)
|
|
readingEmptyStlContainerError(tok);
|
|
} else {
|
|
// Unknown usage. Assume it is initialized.
|
|
empty.erase(tok->varId());
|
|
}
|
|
}
|
|
|
|
void CheckStl::readingEmptyStlContainer()
|
|
{
|
|
if (!_settings->isEnabled(Settings::STYLE))
|
|
return;
|
|
|
|
if (!_settings->inconclusive)
|
|
return;
|
|
|
|
std::map<unsigned int, const Library::Container*> emptyContainer;
|
|
|
|
const std::list<Scope>& scopeList = _tokenizer->getSymbolDatabase()->scopeList;
|
|
|
|
for (std::list<Scope>::const_iterator i = scopeList.begin(); i != scopeList.end(); ++i) {
|
|
if (i->type != Scope::eFunction)
|
|
continue;
|
|
|
|
for (const Token *tok = i->classStart->next(); tok != i->classEnd; tok = tok->next()) {
|
|
if (Token::Match(tok, "for|while")) { // Loops and end of scope clear the sets.
|
|
const Token* tok2 = tok->linkAt(1);
|
|
if (!tok2)
|
|
continue;
|
|
tok2 = tok2->next();
|
|
for (const Token* end2 = tok2->link(); tok2 && tok2 != end2; tok2 = tok2->next()) {
|
|
if (!tok2->varId())
|
|
continue;
|
|
|
|
const std::map<unsigned int, const Library::Container*>::const_iterator container = emptyContainer.find(tok2->varId());
|
|
if (container == emptyContainer.end())
|
|
continue;
|
|
|
|
readingEmptyStlContainer_parseUsage(tok2, container->second, emptyContainer, true);
|
|
}
|
|
} else if (Token::Match(tok, "do|}|break|case")) {
|
|
emptyContainer.clear();
|
|
} else if (tok->str() == "{" && tok->next()->scope()->type == Scope::eLambda)
|
|
tok = tok->link();
|
|
|
|
// function call
|
|
if (Token::Match(tok, "!!. %name% (") && !Token::simpleMatch(tok->linkAt(2), ") {")) {
|
|
for (std::map<unsigned int, const Library::Container*>::iterator it = emptyContainer.begin(); it != emptyContainer.end();) {
|
|
const Variable *var = _tokenizer->getSymbolDatabase()->getVariableFromVarId(it->first);
|
|
if (var && (var->isLocal() || var->isArgument()))
|
|
++it;
|
|
else
|
|
emptyContainer.erase(it++);
|
|
}
|
|
}
|
|
|
|
if (!tok->varId())
|
|
continue;
|
|
|
|
// Check whether a variable should be marked as "empty"
|
|
const Variable* var = tok->variable();
|
|
if (var && !var->isArrayOrPointer() && !var->typeStartToken()->isStandardType()) {
|
|
bool insert = false;
|
|
if (var->nameToken() == tok && var->isLocal() && !var->isStatic()) { // Local variable declared
|
|
insert = !Token::Match(tok->next(), "[(=:]"); // Only if not initialized
|
|
} else if (Token::Match(tok, "%var% . clear ( ) ;")) {
|
|
insert = true;
|
|
}
|
|
|
|
if (insert) {
|
|
const Library::Container* container = _settings->library.detectContainer(var->typeStartToken());
|
|
if (container)
|
|
emptyContainer[var->declarationId()] = container;
|
|
continue;
|
|
}
|
|
}
|
|
|
|
const std::map<unsigned int, const Library::Container*>::const_iterator container = emptyContainer.find(tok->varId());
|
|
if (container == emptyContainer.end())
|
|
continue;
|
|
|
|
readingEmptyStlContainer_parseUsage(tok, container->second, emptyContainer, false);
|
|
}
|
|
emptyContainer.clear();
|
|
}
|
|
}
|
|
|
|
void CheckStl::readingEmptyStlContainerError(const Token *tok)
|
|
{
|
|
reportError(tok, Severity::style, "reademptycontainer", "Reading from empty STL container '" + (tok ? tok->str() : std::string("var")) + "'", CWE398, true);
|
|
}
|