360 lines
14 KiB
C++
360 lines
14 KiB
C++
/*
|
|
* Cppcheck - A tool for static C/C++ code analysis
|
|
* Copyright (C) 2007-2016 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/>.
|
|
*/
|
|
|
|
|
|
//---------------------------------------------------------------------------
|
|
#include "astutils.h"
|
|
#include "symboldatabase.h"
|
|
#include "token.h"
|
|
#include "tokenize.h"
|
|
#include <set>
|
|
|
|
bool astIsSignedChar(const Token *tok)
|
|
{
|
|
return tok && tok->valueType() && tok->valueType()->sign == ValueType::Sign::SIGNED && tok->valueType()->type == ValueType::Type::CHAR && tok->valueType()->pointer == 0U;
|
|
}
|
|
|
|
bool astIsIntegral(const Token *tok, bool unknown)
|
|
{
|
|
const ValueType *vt = tok ? tok->valueType() : nullptr;
|
|
if (!vt)
|
|
return unknown;
|
|
return vt->isIntegral() && vt->pointer == 0U;
|
|
}
|
|
|
|
bool astIsFloat(const Token *tok, bool unknown)
|
|
{
|
|
const ValueType *vt = tok ? tok->valueType() : nullptr;
|
|
if (!vt)
|
|
return unknown;
|
|
return vt->type >= ValueType::Type::FLOAT && vt->pointer == 0U;
|
|
}
|
|
|
|
bool astIsBool(const Token *tok)
|
|
{
|
|
return tok && (tok->isBoolean() || tok->valueType() && tok->valueType()->type == ValueType::Type::BOOL);
|
|
}
|
|
|
|
std::string astCanonicalType(const Token *expr)
|
|
{
|
|
if (!expr)
|
|
return "";
|
|
if (expr->variable()) {
|
|
const Variable *var = expr->variable();
|
|
std::string ret;
|
|
for (const Token *type = var->typeStartToken(); Token::Match(type,"%name%|::") && type != var->nameToken(); type = type->next()) {
|
|
if (!Token::Match(type, "const|static"))
|
|
ret += type->str();
|
|
}
|
|
return ret;
|
|
|
|
}
|
|
// TODO: handle expressions
|
|
return "";
|
|
}
|
|
|
|
const Token * astIsVariableComparison(const Token *tok, const std::string &comp, const std::string &rhs, const Token **vartok)
|
|
{
|
|
if (!tok)
|
|
return nullptr;
|
|
|
|
const Token *ret = nullptr;
|
|
if (tok->isComparisonOp()) {
|
|
if (tok->astOperand1() && tok->astOperand1()->str() == rhs) {
|
|
// Invert comparator
|
|
std::string s = tok->str();
|
|
if (s[0] == '>')
|
|
s[0] = '<';
|
|
else if (s[0] == '<')
|
|
s[0] = '>';
|
|
if (s == comp) {
|
|
ret = tok->astOperand2();
|
|
}
|
|
} else if (tok->str() == comp && tok->astOperand2() && tok->astOperand2()->str() == rhs) {
|
|
ret = tok->astOperand1();
|
|
}
|
|
} else if (comp == "!=" && rhs == std::string("0")) {
|
|
ret = tok;
|
|
} else if (comp == "==" && rhs == std::string("0")) {
|
|
if (tok->str() == "!")
|
|
ret = tok->astOperand1();
|
|
}
|
|
while (ret && ret->str() == ".")
|
|
ret = ret->astOperand2();
|
|
if (ret && ret->varId() == 0U)
|
|
ret = nullptr;
|
|
if (vartok)
|
|
*vartok = ret;
|
|
return ret;
|
|
}
|
|
|
|
bool isSameExpression(bool cpp, bool macro, const Token *tok1, const Token *tok2, const std::set<std::string> &constFunctions)
|
|
{
|
|
if (tok1 == nullptr && tok2 == nullptr)
|
|
return true;
|
|
if (tok1 == nullptr || tok2 == nullptr)
|
|
return false;
|
|
if (cpp) {
|
|
if (tok1->str() == "." && tok1->astOperand1() && tok1->astOperand1()->str() == "this")
|
|
tok1 = tok1->astOperand2();
|
|
if (tok2->str() == "." && tok2->astOperand1() && tok2->astOperand1()->str() == "this")
|
|
tok2 = tok2->astOperand2();
|
|
}
|
|
if (tok1->varId() != tok2->varId() || tok1->str() != tok2->str() || tok1->originalName() != tok2->originalName()) {
|
|
if ((Token::Match(tok1,"<|>") && Token::Match(tok2,"<|>")) ||
|
|
(Token::Match(tok1,"<=|>=") && Token::Match(tok2,"<=|>="))) {
|
|
return isSameExpression(cpp, macro, tok1->astOperand1(), tok2->astOperand2(), constFunctions) &&
|
|
isSameExpression(cpp, macro, tok1->astOperand2(), tok2->astOperand1(), constFunctions);
|
|
}
|
|
return false;
|
|
}
|
|
if (macro && (tok1->isExpandedMacro() || tok2->isExpandedMacro()))
|
|
return false;
|
|
if (tok1->isName() && tok1->next()->str() == "(" && tok1->str() != "sizeof") {
|
|
if (!tok1->function() && !Token::Match(tok1->previous(), ".|::") && constFunctions.find(tok1->str()) == constFunctions.end() && !tok1->isAttributeConst() && !tok1->isAttributePure())
|
|
return false;
|
|
else if (tok1->function() && !tok1->function()->isConst() && !tok1->function()->isAttributeConst() && !tok1->function()->isAttributePure())
|
|
return false;
|
|
}
|
|
// templates/casts
|
|
if ((Token::Match(tok1, "%name% <") && tok1->next()->link()) ||
|
|
(Token::Match(tok2, "%name% <") && tok2->next()->link())) {
|
|
|
|
// non-const template function that is not a dynamic_cast => return false
|
|
if (Token::simpleMatch(tok1->next()->link(), "> (") &&
|
|
!(tok1->function() && tok1->function()->isConst()) &&
|
|
tok1->str() != "dynamic_cast")
|
|
return false;
|
|
|
|
// some template/cast stuff.. check that the template arguments are same
|
|
const Token *t1 = tok1->next();
|
|
const Token *t2 = tok2->next();
|
|
const Token *end1 = t1->link();
|
|
const Token *end2 = t2->link();
|
|
while (t1 && t2 && t1 != end1 && t2 != end2) {
|
|
if (t1->str() != t2->str())
|
|
return false;
|
|
t1 = t1->next();
|
|
t2 = t2->next();
|
|
}
|
|
if (t1 != end1 || t2 != end2)
|
|
return false;
|
|
}
|
|
if (tok1->tokType() == Token::eIncDecOp || tok1->isAssignmentOp())
|
|
return false;
|
|
// bailout when we see ({..})
|
|
if (tok1->str() == "{")
|
|
return false;
|
|
if (tok1->str() == "(" && tok1->previous() && !tok1->previous()->isName()) { // cast => assert that the casts are equal
|
|
const Token *t1 = tok1->next();
|
|
const Token *t2 = tok2->next();
|
|
while (t1 && t2 && t1->str() == t2->str() && (t1->isName() || t1->str() == "*")) {
|
|
t1 = t1->next();
|
|
t2 = t2->next();
|
|
}
|
|
if (!t1 || !t2 || t1->str() != ")" || t2->str() != ")")
|
|
return false;
|
|
}
|
|
bool noncommuative_equals =
|
|
isSameExpression(cpp, macro, tok1->astOperand1(), tok2->astOperand1(), constFunctions);
|
|
noncommuative_equals = noncommuative_equals &&
|
|
isSameExpression(cpp, macro, tok1->astOperand2(), tok2->astOperand2(), constFunctions);
|
|
|
|
if (noncommuative_equals)
|
|
return true;
|
|
|
|
const bool commutative = tok1->astOperand1() && tok1->astOperand2() && Token::Match(tok1, "%or%|%oror%|+|*|&|&&|^|==|!=");
|
|
bool commuative_equals = commutative &&
|
|
isSameExpression(cpp, macro, tok1->astOperand2(), tok2->astOperand1(), constFunctions);
|
|
commuative_equals = commuative_equals &&
|
|
isSameExpression(cpp, macro, tok1->astOperand1(), tok2->astOperand2(), constFunctions);
|
|
|
|
// in c++, "a"+b might be different to b+"a"
|
|
if (cpp && commuative_equals && tok1->str() == "+" &&
|
|
(tok1->astOperand1()->tokType() == Token::eString || tok1->astOperand2()->tokType() == Token::eString)) {
|
|
const Token * const other = tok1->astOperand1()->tokType() != Token::eString ? tok1->astOperand1() : tok1->astOperand2();
|
|
return other && astIsIntegral(other,false);
|
|
}
|
|
|
|
return commuative_equals;
|
|
}
|
|
|
|
bool isOppositeCond(bool isNot, bool cpp, const Token * const cond1, const Token * const cond2, const std::set<std::string> &constFunctions)
|
|
{
|
|
if (!cond1 || !cond2)
|
|
return false;
|
|
|
|
if (cond1->str() == "!") {
|
|
if (cond2->str() == "!=") {
|
|
if (cond2->astOperand1() && cond2->astOperand1()->str() == "0")
|
|
return isSameExpression(cpp, true, cond1->astOperand1(), cond2->astOperand2(), constFunctions);
|
|
if (cond2->astOperand2() && cond2->astOperand2()->str() == "0")
|
|
return isSameExpression(cpp, true, cond1->astOperand1(), cond2->astOperand1(), constFunctions);
|
|
}
|
|
return isSameExpression(cpp, true, cond1->astOperand1(), cond2, constFunctions);
|
|
}
|
|
|
|
if (cond2->str() == "!")
|
|
return isOppositeCond(isNot, cpp, cond2, cond1, constFunctions);
|
|
|
|
if (!cond1->isComparisonOp() || !cond2->isComparisonOp())
|
|
return false;
|
|
|
|
const std::string &comp1 = cond1->str();
|
|
|
|
// condition found .. get comparator
|
|
std::string comp2;
|
|
if (isSameExpression(cpp, true, cond1->astOperand1(), cond2->astOperand1(), constFunctions) &&
|
|
isSameExpression(cpp, true, cond1->astOperand2(), cond2->astOperand2(), constFunctions)) {
|
|
comp2 = cond2->str();
|
|
} else if (isSameExpression(cpp, true, cond1->astOperand1(), cond2->astOperand2(), constFunctions) &&
|
|
isSameExpression(cpp, true, cond1->astOperand2(), cond2->astOperand1(), constFunctions)) {
|
|
comp2 = cond2->str();
|
|
if (comp2[0] == '>')
|
|
comp2[0] = '<';
|
|
else if (comp2[0] == '<')
|
|
comp2[0] = '>';
|
|
}
|
|
|
|
// is condition opposite?
|
|
return ((comp1 == "==" && comp2 == "!=") ||
|
|
(comp1 == "!=" && comp2 == "==") ||
|
|
(comp1 == "<" && comp2 == ">=") ||
|
|
(comp1 == "<=" && comp2 == ">") ||
|
|
(comp1 == ">" && comp2 == "<=") ||
|
|
(comp1 == ">=" && comp2 == "<") ||
|
|
(!isNot && ((comp1 == "<" && comp2 == ">") ||
|
|
(comp1 == ">" && comp2 == "<"))));
|
|
}
|
|
|
|
bool isConstExpression(const Token *tok, const std::set<std::string> &constFunctions)
|
|
{
|
|
if (!tok)
|
|
return true;
|
|
if (tok->isName() && tok->next()->str() == "(") {
|
|
if (!tok->function() && !Token::Match(tok->previous(), ".|::") && constFunctions.find(tok->str()) == constFunctions.end())
|
|
return false;
|
|
else if (tok->function() && !tok->function()->isConst())
|
|
return false;
|
|
}
|
|
if (tok->tokType() == Token::eIncDecOp)
|
|
return false;
|
|
// bailout when we see ({..})
|
|
if (tok->str() == "{")
|
|
return false;
|
|
return isConstExpression(tok->astOperand1(),constFunctions) && isConstExpression(tok->astOperand2(),constFunctions);
|
|
}
|
|
|
|
bool isWithoutSideEffects(bool cpp, const Token* tok)
|
|
{
|
|
if (!cpp)
|
|
return true;
|
|
|
|
while (tok && tok->astOperand2() && tok->astOperand2()->str() != "(")
|
|
tok = tok->astOperand2();
|
|
if (tok && tok->varId()) {
|
|
const Variable* var = tok->variable();
|
|
return var && (!var->isClass() || var->isPointer() || var->isStlType());
|
|
}
|
|
return true;
|
|
}
|
|
|
|
bool isReturnScope(const Token * const endToken)
|
|
{
|
|
if (!endToken || endToken->str() != "}")
|
|
return false;
|
|
|
|
const Token *prev = endToken->previous();
|
|
while (prev && Token::simpleMatch(prev->previous(), "; ;"))
|
|
prev = prev->previous();
|
|
if (prev && Token::simpleMatch(prev->previous(), "} ;"))
|
|
prev = prev->previous();
|
|
|
|
if (Token::simpleMatch(prev, "}")) {
|
|
if (Token::simpleMatch(prev->link()->tokAt(-2), "} else {"))
|
|
return isReturnScope(prev) && isReturnScope(prev->link()->tokAt(-2));
|
|
if (Token::simpleMatch(prev->link()->previous(), ") {") &&
|
|
Token::simpleMatch(prev->link()->linkAt(-1)->previous(), "switch (") &&
|
|
!Token::findsimplematch(prev->link(), "break", prev)) {
|
|
return true;
|
|
}
|
|
if (Token::simpleMatch(prev->link()->previous(), ") {") &&
|
|
Token::simpleMatch(prev->link()->linkAt(-1)->previous(), "return (")) {
|
|
return true;
|
|
}
|
|
if (Token::Match(prev->link()->previous(), "[;{}] {"))
|
|
return isReturnScope(prev);
|
|
} else if (Token::simpleMatch(prev, ";")) {
|
|
// noreturn function
|
|
if (Token::simpleMatch(prev->previous(), ") ;") && Token::Match(prev->linkAt(-1)->tokAt(-2), "[;{}] %name% ("))
|
|
return true;
|
|
// return/goto statement
|
|
prev = prev->previous();
|
|
while (prev && !Token::Match(prev, ";|{|}|return|goto|throw|continue|break"))
|
|
prev = prev->previous();
|
|
return prev && prev->isName();
|
|
}
|
|
return false;
|
|
}
|
|
|
|
bool isVariableChanged(const Token *start, const Token *end, const unsigned int varid)
|
|
{
|
|
for (const Token *tok = start; tok != end; tok = tok->next()) {
|
|
if (tok->varId() == varid) {
|
|
if (Token::Match(tok, "%name% %assign%|++|--"))
|
|
return true;
|
|
|
|
if (Token::Match(tok->previous(), "++|-- %name%"))
|
|
return true;
|
|
|
|
if (Token::Match(tok->tokAt(-2), "[(,] & %var% [,)]"))
|
|
return true; // TODO: check if function parameter is const
|
|
|
|
if (Token::Match(tok->previous(), "[(,] %var% [,)]")) {
|
|
const Token *parent = tok->astParent();
|
|
while (parent && parent->str() == ",")
|
|
parent = parent->astParent();
|
|
if (parent && Token::Match(parent->previous(), "%name% (") && !parent->previous()->function())
|
|
return true;
|
|
// TODO: check if function parameter is non-const reference etc..
|
|
}
|
|
|
|
const Token *parent = tok->astParent();
|
|
while (Token::Match(parent, ".|::"))
|
|
parent = parent->astParent();
|
|
if (parent && parent->tokType() == Token::eIncDecOp)
|
|
return true;
|
|
}
|
|
}
|
|
return false;
|
|
}
|
|
|
|
int numberOfArguments(const Token *start)
|
|
{
|
|
int arguments=0;
|
|
const Token* const openBracket = start->next();
|
|
if (openBracket && openBracket->str()=="(" && openBracket->next() && openBracket->next()->str()!=")") {
|
|
const Token* argument=openBracket->next();
|
|
while (argument) {
|
|
++arguments;
|
|
argument = argument->nextArgument();
|
|
}
|
|
}
|
|
return arguments;
|
|
}
|