Method overlappingStrcmp

lib/checkstring.cpp:344–404

--------------------------------------------------------------------------- always true: strcmp(str,"a")==0 || strcmp(str,"b") TODO: Library configuration for string comparison functions ---------------------------------------------------------------------------

// TODO: Library configuration for string comparison functions
//---------------------------------------------------------------------------
void CheckStringImpl::overlappingStrcmp()
{
    if (!mSettings.severity.isEnabled(Severity::warning))
        return;

    logChecker("CheckString::overlappingStrcmp"); // warning

    const SymbolDatabase *symbolDatabase = mTokenizer->getSymbolDatabase();
    for (const Scope * scope : symbolDatabase->functionScopes) {
        for (const Token* tok = scope->bodyStart->next(); tok != scope->bodyEnd; tok = tok->next()) {
            if (tok->str() != "||")
                continue;
            std::list<const Token *> equals0;
            std::list<const Token *> notEquals0;
            visitAstNodes(tok, [&](const Token * t) {
                if (!t)
                    return ChildrenToVisit::none;
                if (t->str() == "||") {
                    return ChildrenToVisit::op1_and_op2;
                }
                if (t->str() == "==") {
                    if (Token::simpleMatch(t->astOperand1(), "(") && Token::simpleMatch(t->astOperand2(), "0"))
                        equals0.push_back(t->astOperand1());
                    else if (Token::simpleMatch(t->astOperand2(), "(") && Token::simpleMatch(t->astOperand1(), "0"))
                        equals0.push_back(t->astOperand2());
                    return ChildrenToVisit::none;
                }
                if (t->str() == "!=") {
                    if (Token::simpleMatch(t->astOperand1(), "(") && Token::simpleMatch(t->astOperand2(), "0"))
                        notEquals0.push_back(t->astOperand1());
                    else if (Token::simpleMatch(t->astOperand2(), "(") && Token::simpleMatch(t->astOperand1(), "0"))
                        notEquals0.push_back(t->astOperand2());
                    return ChildrenToVisit::none;
                }
                if (t->str() == "!" && Token::simpleMatch(t->astOperand1(), "("))
                    equals0.push_back(t->astOperand1());
                else if (t->str() == "(")
                    notEquals0.push_back(t);
                return ChildrenToVisit::none;
            });

            for (const Token *eq0 : equals0) {
                for (const Token * ne0 : notEquals0) {
                    if (!Token::Match(eq0->previous(), "strcmp|wcscmp ("))
                        continue;
                    if (!Token::Match(ne0->previous(), "strcmp|wcscmp ("))
                        continue;
                    const std::vector<const Token *> args1 = getArguments(eq0->previous());
                    const std::vector<const Token *> args2 = getArguments(ne0->previous());
                    if (args1.size() != 2 || args2.size() != 2)
                        continue;
                    if (args1[1]->isLiteral() &&
                        args2[1]->isLiteral() &&
                        args1[1]->str() != args2[1]->str() &&
                        isSameExpression(true, args1[0], args2[0], mSettings, true, false))
                        overlappingStrcmpError(eq0, ne0);
                }
            }