/* * Cppcheck - A tool for static C/C++ code analysis * Copyright (C) 2007-2010 Daniel Marjamäki and Cppcheck team. * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see . */ //--------------------------------------------------------------------------- #include "checkclass.h" #include "tokenize.h" #include "token.h" #include "errorlogger.h" #include #include #include #include #include //--------------------------------------------------------------------------- // Register CheckClass.. namespace { CheckClass instance; } //--------------------------------------------------------------------------- CheckClass::Var *CheckClass::getVarList(const Token *tok1, bool withClasses, bool isStruct) { // Get variable list.. Var *varlist = NULL; unsigned int indentlevel = 0; bool priv = !isStruct; for (const Token *tok = tok1; tok; tok = tok->next()) { if (!tok->next()) break; if (tok->str() == "{") ++indentlevel; else if (tok->str() == "}") { if (indentlevel <= 1) break; --indentlevel; } if (indentlevel != 1) continue; // Borland C++: Skip all variables in the __published section. // These are automaticly initialized. if (tok->str() == "__published:") { priv = false; for (; tok; tok = tok->next()) { if (tok->str() == "{") tok = tok->link(); if (Token::Match(tok->next(), "private:|protected:|public:")) break; } if (tok) continue; else break; } // "private:" "public:" "protected:" etc const bool b((tok->str()[0] != ':') && tok->str().find(":") != std::string::npos); if (b) priv = bool(tok->str() == "private:"); // Search for start of statement.. if (! Token::Match(tok, "[;{}]") && ! b) continue; // This is the start of a statement const Token *next = tok->next(); std::string varname; // If next token contains a ":".. it is not part of a variable declaration if (next->str().find(":") != std::string::npos) continue; // Borland C++: Ignore properties.. if (next->str() == "__property") continue; // Is it a static variable? bool isStatic = false; if (next->str() == "static") { isStatic = true; next = next->next(); } // Is it a mutable variable? bool isMutable = false; if (next->str() == "mutable") { isMutable = true; next = next->next(); } // Is it const..? if (next->str() == "const") { next = next->next(); } // Is it a variable declaration? if (Token::Match(next, "%type% %var% ;|:")) { if (withClasses) varname = next->strAt(1); else if (next->isStandardType()) varname = next->strAt(1); else if (Token::findmatch(_tokenizer->tokens(), ("enum " + next->str()).c_str())) varname = next->strAt(1); } // Structure? else if (Token::Match(next, "struct|union %type% %var% ;")) { varname = next->strAt(2); } // Pointer? else if (Token::Match(next, "%type% * %var% ;")) varname = next->strAt(2); else if (Token::Match(next, "%type% %type% * %var% ;")) varname = next->strAt(3); else if (Token::Match(next, "%type% :: %type% * %var% ;")) varname = next->strAt(4); // Array? else if (Token::Match(next, "%type% %var% [") && next->next()->str() != "operator") { if (!withClasses && !next->isStandardType()) { continue; } varname = next->strAt(1); } // Pointer array? else if (Token::Match(next, "%type% * %var% [")) varname = next->strAt(2); else if (Token::Match(next, "%type% :: %type% * %var% [")) varname = next->strAt(4); // std::string.. else if (withClasses && Token::Match(next, "%type% :: %type% %var% ;")) { varname = next->strAt(3); } // Container.. else if (withClasses && (Token::Match(next, "%type% :: %type% <") || Token::Match(next, "%type% <"))) { // find matching ">" int level = 0; for (; next; next = next->next()) { if (next->str() == "<") level++; else if (next->str() == ">") { level--; if (level == 0) break; } } if (next && Token::Match(next, "> %var% ;")) varname = next->strAt(1); else if (next && Token::Match(next, "> * %var% ;")) varname = next->strAt(2); } // If the varname was set in the if-blocks above, create a entry for this variable.. if (!varname.empty() && varname != "operator") { Var *var = new Var(varname, false, priv, isMutable, isStatic, varlist); varlist = var; } } return varlist; } //--------------------------------------------------------------------------- void CheckClass::initVar(Var *varlist, const std::string &varname) { for (Var *var = varlist; var; var = var->next) { if (var->name == varname) { var->init = true; return; } } } //--------------------------------------------------------------------------- void CheckClass::initializeVarList(const Token *tok1, const Token *ftok, Var *varlist, const std::string &classname, std::list &callstack, bool isStruct) { bool Assign = false; unsigned int indentlevel = 0; for (; ftok; ftok = ftok->next()) { if (!ftok->next()) break; // Class constructor.. initializing variables like this // clKalle::clKalle() : var(value) { } if (indentlevel == 0) { if (Assign && Token::Match(ftok, "%var% (")) { initVar(varlist, ftok->strAt(0)); // assignment in the initializer.. // : var(value = x) if (Token::Match(ftok->tokAt(2), "%var% =")) initVar(varlist, ftok->strAt(2)); } Assign |= (ftok->str() == ":"); } if (ftok->str() == "{") { ++indentlevel; Assign = false; } else if (ftok->str() == "}") { if (indentlevel <= 1) break; --indentlevel; } if (indentlevel < 1) continue; // Variable getting value from stream? if (Token::Match(ftok, ">> %var%")) { initVar(varlist, ftok->strAt(1)); } // Before a new statement there is "[{};)=]" or "else" if (! Token::Match(ftok, "[{};()=]") && ftok->str() != "else") continue; // Using the operator= function to initialize all variables.. if (Token::simpleMatch(ftok->next(), "* this = ")) { for (Var *var = varlist; var; var = var->next) var->init = true; break; } if (!Token::Match(ftok->next(), "%var%") && !Token::Match(ftok->next(), "this . %var%") && !Token::Match(ftok->next(), "* %var% =") && !Token::Match(ftok->next(), "( * this ) . %var%")) continue; // Goto the first token in this statement.. ftok = ftok->next(); // Skip "( * this )" if (Token::simpleMatch(ftok, "( * this ) .")) { ftok = ftok->tokAt(5); } // Skip "this->" if (Token::simpleMatch(ftok, "this .")) ftok = ftok->tokAt(2); // Skip "classname :: " if (Token::Match(ftok, "%var% ::")) ftok = ftok->tokAt(2); // Clearing all variables.. if (Token::simpleMatch(ftok, "memset ( this ,")) { for (Var *var = varlist; var; var = var->next) var->init = true; return; } // Clearing array.. else if (Token::Match(ftok, "memset ( %var% ,")) { initVar(varlist, ftok->strAt(2)); ftok = ftok->next()->link(); continue; } // Calling member function? else if (Token::Match(ftok, "%var% (")) { // Passing "this" => assume that everything is initialized for (const Token * tok2 = ftok->next()->link(); tok2 && tok2 != ftok; tok2 = tok2->previous()) { if (tok2->str() == "this") { for (Var *var = varlist; var; var = var->next) var->init = true; return; } } if (ftok->str() == "if") continue; // No recursive calls! if (std::find(callstack.begin(), callstack.end(), ftok->str()) == callstack.end()) { int i = 0; const Token *ftok2 = _tokenizer->findClassFunction(tok1, classname, ftok->strAt(0), i, isStruct); if (ftok2) { callstack.push_back(ftok->str()); initializeVarList(tok1, ftok2, varlist, classname, callstack, isStruct); callstack.pop_back(); } else // there is a called member function, but it is not defined where we can find it, so we assume it initializes everything { // check if the function is part of this class.. const Token *tok = Token::findmatch(_tokenizer->tokens(), (std::string("class ") + classname + " {").c_str()); for (tok = tok ? tok->tokAt(3) : 0; tok; tok = tok->next()) { if (tok->str() == "{") { tok = tok->link(); if (!tok) break; } else if (tok->str() == "}") { break; } else if (tok->str() == ftok->str() || tok->str() == "friend") { tok = 0; break; } } // bail out.. if (!tok) { for (Var *var = varlist; var; var = var->next) var->init = true; break; } // the function is external and it's neither friend nor inherited virtual function. // assume all variables that are passed to it are initialized.. unsigned int indentlevel2 = 0; for (tok = ftok->tokAt(2); tok; tok = tok->next()) { if (tok->str() == "(") ++indentlevel2; else if (tok->str() == ")") { if (indentlevel2 == 0) break; --indentlevel2; } if (tok->isName()) { initVar(varlist, tok->strAt(0)); } } continue; } } } // Assignment of member variable? else if (Token::Match(ftok, "%var% =")) { initVar(varlist, ftok->strAt(0)); } // Assignment of array item of member variable? else if (Token::Match(ftok, "%var% [ %any% ] =")) { initVar(varlist, ftok->strAt(0)); } // Assignment of array item of member variable? else if (Token::Match(ftok, "%var% [ %any% ] [ %any% ] =")) { initVar(varlist, ftok->strAt(0)); } // Assignment of array item of member variable? else if (Token::Match(ftok, "* %var% =")) { initVar(varlist, ftok->strAt(1)); } // Assignment of struct member of member variable? else if (Token::Match(ftok, "%var% . %any% =")) { initVar(varlist, ftok->strAt(0)); } // The functions 'clear' and 'Clear' are supposed to initialize variable. if (Token::Match(ftok, "%var% . clear|Clear (")) { initVar(varlist, ftok->strAt(0)); } } } //--------------------------------------------------------------------------- // ClassCheck: Check that all class constructors are ok. //--------------------------------------------------------------------------- void CheckClass::constructors() { if (!_settings->_checkCodingStyle) return; const char pattern_class[] = "class|struct %var% [{:]"; // Locate class const Token *tok1 = Token::findmatch(_tokenizer->tokens(), pattern_class); while (tok1) { const std::string className = tok1->strAt(1); const Token *classNameToken = tok1->tokAt(1); bool isStruct = tok1->str() == "struct"; /** @todo handling of private constructors should be improved */ bool hasPrivateConstructor = false; { int indentlevel = 0; bool isPrivate = !isStruct; for (const Token *tok = tok1; tok; tok = tok->next()) { // Indentation if (tok->str() == "{") ++indentlevel; else if (tok->str() == "}") { --indentlevel; if (indentlevel <= 0) break; } // Parse class contents (indentlevel == 1).. if (indentlevel == 1) { // What section are we in.. private/non-private if (tok->str() == "private:") isPrivate = true; else if (tok->str() == "protected:" || tok->str() == "public:") isPrivate = false; // Is there a private constructor? else if (isPrivate && Token::simpleMatch(tok, (classNameToken->str() + " (").c_str())) { hasPrivateConstructor = true; break; } } } } if (hasPrivateConstructor && !_settings->inconclusive) { /** @todo Handle private constructors. Right now to avoid * false positives we just bail out */ tok1 = Token::findmatch(tok1->next(), pattern_class); continue; } // Are there a class constructor? std::string tempPattern = "%any% " + classNameToken->str() + " ("; const Token *constructor_token = Token::findmatch(tok1, tempPattern.c_str()); while (constructor_token && constructor_token->str() == "~") constructor_token = Token::findmatch(constructor_token->next(), tempPattern.c_str()); // There are no constructor. if (! constructor_token) { // If "--style" has been given, give a warning if (_settings->_checkCodingStyle) { // Get class variables... Var *varlist = getVarList(tok1, false, isStruct); // If there is a private variable, there should be a constructor.. for (const Var *var = varlist; var; var = var->next) { if (var->priv && !var->isStatic) { noConstructorError(tok1, classNameToken->str(), isStruct); break; } } // Delete the varlist.. while (varlist) { Var *nextvar = varlist->next; delete varlist; varlist = nextvar; } } tok1 = Token::findmatch(tok1->next(), pattern_class); continue; } // Check constructors checkConstructors(tok1, className, hasPrivateConstructor, isStruct); // Check assignment operators checkConstructors(tok1, "operator =", hasPrivateConstructor, isStruct); tok1 = Token::findmatch(tok1->next(), pattern_class); } } void CheckClass::checkConstructors(const Token *tok1, const std::string &funcname, bool hasPrivateConstructor, bool isStruct) { const std::string className = tok1->strAt(1); // Check that all member variables are initialized.. const bool withClasses = bool(_settings->inconclusive && funcname == "operator ="); Var *varlist = getVarList(tok1, withClasses, isStruct); int indentlevel = 0; const Token *constructor_token = _tokenizer->findClassFunction(tok1, className, funcname, indentlevel, isStruct); std::list callstack; initializeVarList(tok1, constructor_token, varlist, className, callstack, isStruct); while (constructor_token) { // Check if any variables are uninitialized for (Var *var = varlist; var; var = var->next) { if (var->init || var->isStatic) continue; // It's non-static and it's not initialized => error if (Token::simpleMatch(constructor_token, "operator = (") || Token::simpleMatch(constructor_token->tokAt(2), "operator = (")) { const Token *operStart = 0; if (Token::simpleMatch(constructor_token, "operator = (")) operStart = constructor_token->tokAt(2); else operStart = constructor_token->tokAt(4); bool classNameUsed = false; for (const Token *operTok = operStart; operTok != operStart->link(); operTok = operTok->next()) { if (operTok->str() == className) { classNameUsed = true; break; } } if (classNameUsed) operatorEqVarError(constructor_token, className, var->name); } else if (!hasPrivateConstructor && !var->isStatic) uninitVarError(constructor_token, className, var->name); } for (Var *var = varlist; var; var = var->next) var->init = false; constructor_token = _tokenizer->findClassFunction(constructor_token->next(), className, funcname, indentlevel, isStruct); callstack.clear(); initializeVarList(tok1, constructor_token, varlist, className, callstack, isStruct); } // Delete the varlist.. while (varlist) { Var *nextvar = varlist->next; delete varlist; varlist = nextvar; } } //--------------------------------------------------------------------------- // ClassCheck: Unused private functions //--------------------------------------------------------------------------- void CheckClass::privateFunctions() { if (!_settings->_checkCodingStyle) return; // Locate some class for (const Token *tok1 = Token::findmatch(_tokenizer->tokens(), "class|struct %var% {"); tok1; tok1 = Token::findmatch(tok1->next(), "class|struct %var% {")) { /** @todo check that the whole class implementation is seen */ // until the todo above is fixed we only check classes that are // declared in the source file if (tok1->fileIndex() != 0) continue; const std::string &classname = tok1->next()->str(); // Get private functions.. std::list FuncList; FuncList.clear(); bool isStruct = tok1->str() == "struct"; bool priv = !isStruct; unsigned int indent_level = 0; for (const Token *tok = tok1; tok; tok = tok->next()) { if (Token::Match(tok, "friend %var%")) { /** @todo Handle friend classes */ FuncList.clear(); break; } if (tok->str() == "{") ++indent_level; else if (tok->str() == "}") { if (indent_level <= 1) break; --indent_level; } else if (indent_level != 1) continue; else if (tok->str() == "private:") priv = true; else if (tok->str() == "public:") priv = false; else if (tok->str() == "protected:") priv = false; else if (priv) { if (Token::Match(tok, "typedef %type% (")) tok = tok->tokAt(2)->link(); else if (Token::Match(tok, "[:,] %var% (")) tok = tok->tokAt(2)->link(); else if (Token::Match(tok, "%var% (") && !Token::simpleMatch(tok->next()->link(), ") (") && !Token::Match(tok, classname.c_str())) { FuncList.push_back(tok); } } /** @todo embedded class have access to private functions */ if (tok->str() == "class") { FuncList.clear(); break; } } // Check that all private functions are used.. bool HasFuncImpl = false; bool inclass = false; indent_level = 0; for (const Token *ftok = _tokenizer->tokens(); ftok; ftok = ftok->next()) { if (ftok->str() == "{") ++indent_level; else if (ftok->str() == "}") { if (indent_level > 0) --indent_level; if (indent_level == 0) inclass = false; } if (Token::Match(ftok, ("class " + classname + " :|{").c_str())) { indent_level = 0; inclass = true; } // Check member class functions to see what functions are used.. if ((inclass && indent_level == 1 && Token::Match(ftok, "%var% (")) || (Token::Match(ftok, (classname + " :: ~| %var% (").c_str()))) { while (ftok && ftok->str() != ")") ftok = ftok->next(); if (!ftok) break; if (Token::Match(ftok, ") : %var% (")) { while (!Token::Match(ftok->next(), "[{};]")) { if (Token::Match(ftok, "::|,|( %var% ,|)")) { // Remove function from FuncList std::list::iterator it = FuncList.begin(); while (it != FuncList.end()) { if (ftok->next()->str() == (*it)->str()) FuncList.erase(it++); else it++; } } ftok = ftok->next(); } } if (!Token::Match(ftok, ") const| {")) continue; if (ftok->fileIndex() == 0) HasFuncImpl = true; // Parse function.. int indentlevel2 = 0; for (const Token *tok2 = ftok; tok2; tok2 = tok2->next()) { if (tok2->str() == "{") ++indentlevel2; else if (tok2->str() == "}") { --indentlevel2; if (indentlevel2 < 1) break; } else if (Token::Match(tok2, "%var% (")) { // Remove function from FuncList std::list::iterator it = FuncList.begin(); while (it != FuncList.end()) { if (tok2->str() == (*it)->str()) FuncList.erase(it++); else it++; } } } } } while (HasFuncImpl && !FuncList.empty()) { // Final check; check if the function pointer is used somewhere.. const std::string _pattern("return|(|)|,|= " + FuncList.front()->str()); if (!Token::findmatch(_tokenizer->tokens(), _pattern.c_str())) { unusedPrivateFunctionError(FuncList.front(), classname, FuncList.front()->str()); } FuncList.pop_front(); } } } //--------------------------------------------------------------------------- // ClassCheck: Check that memset is not used on classes //--------------------------------------------------------------------------- void CheckClass::noMemset() { // Locate all 'memset' tokens.. for (const Token *tok = _tokenizer->tokens(); tok; tok = tok->next()) { if (!Token::Match(tok, "memset|memcpy|memmove")) continue; std::string type; if (Token::Match(tok, "memset ( %var% , %num% , sizeof ( %type% ) )")) type = tok->strAt(8); else if (Token::Match(tok, "memset ( & %var% , %num% , sizeof ( %type% ) )")) type = tok->strAt(9); else if (Token::Match(tok, "memset ( %var% , %num% , sizeof ( struct %type% ) )")) type = tok->strAt(9); else if (Token::Match(tok, "memset ( & %var% , %num% , sizeof ( struct %type% ) )")) type = tok->strAt(10); else if (Token::Match(tok, "%type% ( %var% , %var% , sizeof ( %type% ) )")) type = tok->strAt(8); // No type defined => The tokens didn't match if (type.empty()) continue; // Warn if type is a class or struct that contains any std::* variables const std::string pattern2(std::string("struct|class ") + type + " {"); for (const Token *tstruct = Token::findmatch(_tokenizer->tokens(), pattern2.c_str()); tstruct; tstruct = tstruct->next()) { if (tstruct->str() == "}") break; // struct with function? skip function body.. if (Token::simpleMatch(tstruct, ") {")) { tstruct = tstruct->next()->link(); if (!tstruct) break; } // before a statement there must be either: // * private:|protected:|public: // * { } ; if (Token::Match(tstruct, "[;{}]") || tstruct->str().find(":") != std::string::npos) { if (Token::Match(tstruct->next(), "std :: %type% %var% ;")) memsetStructError(tok, tok->str(), tstruct->strAt(3)); else if (Token::Match(tstruct->next(), "std :: %type% < ")) { // backup the type const std::string typestr(tstruct->strAt(3)); // check if it's a pointer variable.. unsigned int level = 0; while (0 != (tstruct = tstruct->next())) { if (tstruct->str() == "<") ++level; else if (tstruct->str() == ">") { if (level <= 1) break; --level; } else if (tstruct->str() == "(") tstruct = tstruct->link(); } if (!tstruct) break; // found error => report if (Token::Match(tstruct, "> %var% ;")) memsetStructError(tok, tok->str(), typestr); } } } } } //--------------------------------------------------------------------------- //--------------------------------------------------------------------------- // ClassCheck: "void operator=(" //--------------------------------------------------------------------------- void CheckClass::operatorEq() { if (!_settings->_checkCodingStyle) return; const Token *tok2 = _tokenizer->tokens(); const Token *tok; while ((tok = Token::findmatch(tok2, "void operator = (")) != NULL) { const Token *tok1 = tok; while (tok1 && !Token::Match(tok1, "class|struct %var%")) { if (tok1->str() == "public:") { operatorEqReturnError(tok); break; } if (tok1->str() == "private:" || tok1->str() == "protected:") break; tok1 = tok1->previous(); } if (tok1 && Token::Match(tok1, "struct %var%")) operatorEqReturnError(tok); tok2 = tok->next(); } } //--------------------------------------------------------------------------- //--------------------------------------------------------------------------- // ClassCheck: "C& operator=(const C&) { ... return *this; }" // operator= should return a reference to *this //--------------------------------------------------------------------------- // match two lists of tokens static bool nameMatch(const Token * tok1, const Token * tok2, int length) { for (int i = 0; i < length; i++) { if (tok1->tokAt(i) == 0 || tok2->tokAt(i) == 0) return false; if (tok1->tokAt(i)->str() != tok2->tokAt(i)->str()) return false; } return true; } // create a class name from a list of tokens static void nameStr(const Token * name, int length, std::string & str) { for (int i = 0; i < length; i++) { if (i != 0) str += " "; str += name->tokAt(i)->str(); } } void CheckClass::operatorEqRetRefThis_finderr(const Token *tok, const std::string &classname) { // find the ')' const Token *tok1 = tok->tokAt(2)->link(); // is there an implementation? if (Token::simpleMatch(tok1, ") {")) { bool foundReturn = false; const Token *last = tok1->next()->link(); for (tok1 = tok1->tokAt(2); tok1 && tok1 != last; tok1 = tok1->next()) { // check for return of reference to this if (tok1->str() == "return") { foundReturn = true; std::string cast("( " + classname + " & )"); if (Token::Match(tok1->next(), cast.c_str())) tok1 = tok1->tokAt(4); if (!(Token::Match(tok1->tokAt(1), "(| * this ;|=") || Token::Match(tok1->tokAt(1), "(| * this +=") || Token::Match(tok1->tokAt(1), "operator = ("))) operatorEqRetRefThisError(tok); } } if (!foundReturn) operatorEqRetRefThisError(tok); } } void CheckClass::operatorEqRetRefThis() { if (!_settings->_checkCodingStyle) return; const Token *tok2 = _tokenizer->tokens(); const Token *tok; while ((tok = Token::findmatch(tok2, "operator = (")) != NULL) { const Token *tok1 = tok; if (tok1->tokAt(-2) && Token::Match(tok1->tokAt(-2), " %type% ::")) { // make sure this is an assignment operator int nameLength = 1; tok1 = tok1->tokAt(-2); // check backwards for proper function signature while (tok1->tokAt(-2) && Token::Match(tok1->tokAt(-2), " %type% ::")) { tok1 = tok1->tokAt(-2); nameLength += 2; } const Token *className = tok1; std::string nameString; nameStr(className, nameLength, nameString); if (tok1->tokAt(-1) && tok1->tokAt(-1)->str() == "&") { // check class name if (tok1->tokAt(-(1 + nameLength)) && nameMatch(className, tok1->tokAt(-(1 + nameLength)), nameLength)) { operatorEqRetRefThis_finderr(tok, className->str()); } } } else { // make sure this is an assignment operator tok1 = tok; // check backwards for proper function signature if (tok1->tokAt(-1) && tok1->tokAt(-1)->str() == "&") { const Token *className = 0; bool isPublic = false; while (tok1 && !Token::Match(tok1, "class|struct %var%")) { if (!isPublic) { if (tok1->str() == "public:") isPublic = true; } tok1 = tok1->previous(); } if (Token::Match(tok1, "struct|class %var%")) { // data members in structs are public by default isPublic = bool(tok1->str() == "struct"); className = tok1->tokAt(1); } if (tok->tokAt(-2) && tok->tokAt(-2)->str() == className->str()) { operatorEqRetRefThis_finderr(tok, className->str()); } } } tok2 = tok->next(); } } //--------------------------------------------------------------------------- //--------------------------------------------------------------------------- // ClassCheck: "C& operator=(const C& rhs) { if (this == &rhs) ... }" // operator= should check for assignment to self // // For simple classes, an assignment to self check is only a potential optimization. // // For classes that allocate dynamic memory, assignment to self can be a real error // if it is deallocated and allocated again without being checked for. // // This check is not valid for classes with multiple inheritance because a // class can have multiple addresses so there is no trivial way to check for // assignment to self. //--------------------------------------------------------------------------- static bool hasDeallocation(const Token * first, const Token * last) { // This function is called when no simple check was found for assignment // to self. We are currently looking for a specific sequence of: // deallocate member ; ... member = allocate // This check is far from ideal because it can cause false negatives. // Unfortunately, this is necessary to prevent false positives. // This check needs to do careful analysis someday to get this // correct with a high degree of certainty. for (const Token * tok = first; tok && (tok != last); tok = tok->next()) { // check for deallocating memory if (Token::Match(tok, "{|;|, free ( %var%")) { const Token * var = tok->tokAt(3); // we should probably check that var is a pointer in this class const Token * tok1 = tok->tokAt(4); while (tok1 && (tok1 != last)) { if (Token::Match(tok1, "%var% =")) { if (tok1->str() == var->str()) return true; } tok1 = tok1->next(); } } else if (Token::Match(tok, "{|;|, delete [ ] %var%")) { const Token * var = tok->tokAt(4); // we should probably check that var is a pointer in this class const Token * tok1 = tok->tokAt(5); while (tok1 && (tok1 != last)) { if (Token::Match(tok1, "%var% = new %type% [")) { if (tok1->str() == var->str()) return true; } tok1 = tok1->next(); } } else if (Token::Match(tok, "{|;|, delete %var%")) { const Token * var = tok->tokAt(2); // we should probably check that var is a pointer in this class const Token * tok1 = tok->tokAt(3); while (tok1 && (tok1 != last)) { if (Token::Match(tok1, "%var% = new")) { if (tok1->str() == var->str()) return true; } tok1 = tok1->next(); } } } return false; } static bool hasAssignSelf(const Token * first, const Token * last, const Token * rhs) { for (const Token * tok = first; tok && tok != last; tok = tok->next()) { if (Token::Match(tok, "if (")) { const Token * tok1 = tok->tokAt(2); const Token * tok2 = tok->tokAt(1)->link(); if (tok1 && tok2) { for (; tok1 && tok1 != tok2; tok1 = tok1->next()) { if (Token::Match(tok1, "this ==|!= & %var%")) { if (tok1->tokAt(3)->str() == rhs->str()) return true; } else if (Token::Match(tok1, "& %var% ==|!= this")) { if (tok1->tokAt(1)->str() == rhs->str()) return true; } } } } } return false; } static bool hasMultipleInheritanceInline(const Token * tok) { while (tok && tok->str() != "{") { if (tok->str() == ",") return true; tok = tok->next(); } return false; } static bool hasMultipleInheritanceGlobal(const Token * start, const std::string & name) { const Token *tok = start; std::string pattern; std::string className = name; // check for nested classes while (className.find("::") != std::string::npos) { std::string tempName; // there is probably a better way to do this while (className[0] != ' ') { tempName += className[0]; className.erase(0, 1); } className.erase(0, 4); pattern = "class|struct " + tempName; tok = Token::findmatch(tok, pattern.c_str()); } pattern = "class|struct " + className; tok = Token::findmatch(tok, pattern.c_str()); return hasMultipleInheritanceInline(tok); } void CheckClass::operatorEqToSelf() { if (!_settings->_checkCodingStyle) return; const Token *tok2 = _tokenizer->tokens(); const Token *tok; while ((tok = Token::findmatch(tok2, "operator = (")) != NULL) { const Token *tok1 = tok; // make sure this is an assignment operator if (tok1->tokAt(-2) && Token::Match(tok1->tokAt(-2), " %type% ::")) { int nameLength = 1; tok1 = tok1->tokAt(-2); // check backwards for proper function signature while (tok1->tokAt(-2) && Token::Match(tok1->tokAt(-2), " %type% ::")) { tok1 = tok1->tokAt(-2); nameLength += 2; } const Token *className = tok1; std::string nameString; nameStr(className, nameLength, nameString); if (!hasMultipleInheritanceGlobal(_tokenizer->tokens(), nameString)) { if (tok1->tokAt(-1) && tok1->tokAt(-1)->str() == "&") { // check returned class name if (tok1->tokAt(-(1 + nameLength)) && nameMatch(className, tok1->tokAt(-(1 + nameLength)), nameLength)) { // check forward for proper function signature std::string pattern = "const " + nameString + " & %var% )"; if (Token::Match(tok->tokAt(3), pattern.c_str())) { const Token * rhs = tok->tokAt(5 + nameLength); if (nameMatch(className, tok->tokAt(4), nameLength)) { tok1 = tok->tokAt(2)->link(); if (tok1 && tok1->tokAt(1) && tok1->tokAt(1)->str() == "{" && tok1->tokAt(1)->link()) { const Token *first = tok1->tokAt(1); const Token *last = first->link(); if (!hasAssignSelf(first, last, rhs)) { if (hasDeallocation(first, last)) operatorEqToSelfError(tok); } } } } } } } } else { tok1 = tok; // check backwards for proper function signature if (tok1->tokAt(-1) && tok1->tokAt(-1)->str() == "&") { const Token *className = 0; while (tok1 && !Token::Match(tok1, "class|struct %var%")) tok1 = tok1->previous(); if (Token::Match(tok1, "struct|class %var%")) className = tok1->tokAt(1); if (!hasMultipleInheritanceInline(tok1)) { if (Token::simpleMatch(tok->tokAt(-2), className->str().c_str())) { // check forward for proper function signature if (Token::Match(tok->tokAt(3), "const %type% & %var% )")) { const Token * rhs = tok->tokAt(6); if (tok->tokAt(4)->str() == className->str()) { tok1 = tok->tokAt(2)->link(); if (tok1 && Token::simpleMatch(tok1->next(), "{")) { const Token *first = tok1->next(); const Token *last = first->link(); if (!hasAssignSelf(first, last, rhs)) { if (hasDeallocation(first, last)) operatorEqToSelfError(tok); } } } } } } } } tok2 = tok->next(); } } //--------------------------------------------------------------------------- //--------------------------------------------------------------------------- // A destructor in a base class should be virtual //--------------------------------------------------------------------------- void CheckClass::virtualDestructor() { // This error should only be given if: // * base class doesn't have virtual destructor // * derived class has non-empty destructor // * base class is deleted if (!_settings->inconclusive) return; const char pattern_classdecl[] = "class %var% : %var%"; const Token *derived = _tokenizer->tokens(); while ((derived = Token::findmatch(derived, pattern_classdecl)) != NULL) { // Check that the derived class has a non empty destructor.. { std::ostringstream destructorPattern; destructorPattern << "~ " << derived->strAt(1) << " ( ) {"; const Token *derived_destructor = Token::findmatch(_tokenizer->tokens(), destructorPattern.str().c_str()); // No destructor.. if (! derived_destructor) { derived = derived->next(); continue; } // Empty destructor.. if (Token::Match(derived_destructor, "~ %var% ( ) { }")) { derived = derived->next(); continue; } } const Token *derivedClass = derived->tokAt(1); // Iterate through each base class... derived = derived->tokAt(3); while (Token::Match(derived, "%var%")) { bool isPublic(derived->str() == "public"); // What kind of inheritance is it.. public|protected|private if (Token::Match(derived, "public|protected|private")) derived = derived->next(); // Name of base class.. const std::string baseName = derived->strAt(0); // Update derived so it's ready for the next loop. do { if (derived->str() == "{") break; if (derived->str() == ",") { derived = derived->next(); break; } derived = derived->next(); } while (derived); // If not public inheritance, skip checking of this base class.. if (! isPublic) continue; // Find the destructor declaration for the base class. const Token *base = Token::findmatch(_tokenizer->tokens(), (std::string("%any% ~ ") + baseName + " (").c_str()); while (base && base->str() == "::") base = Token::findmatch(base->next(), (std::string("%any% ~ ") + baseName + " (").c_str()); const Token *reverseTok = base; while (Token::Match(base, "%var%") && base->str() != "virtual") base = base->previous(); // Check that there is a destructor.. if (! base) { // Is the class declaration available? base = Token::findmatch(_tokenizer->tokens(), (std::string("class ") + baseName + " {").c_str()); if (base) { virtualDestructorError(base, baseName, derivedClass->str()); } continue; } // There is a destructor. Check that it's virtual.. else if (base->str() == "virtual") continue; // TODO: This is just a temporary fix, better solution is needed. // Skip situations where base class has base classes of its own, because // some of the base classes might have virtual destructor. // Proper solution is to check all of the base classes. If base class is not // found or if one of the base classes has virtual destructor, error should not // be printed. See TODO test case "virtualDestructorInherited" if (!Token::findmatch(_tokenizer->tokens(), (std::string("class ") + baseName + " {").c_str())) continue; // Make sure that the destructor is public (protected or private // would not compile if inheritance is used in a way that would // cause the bug we are trying to find here.) int indent = 0; while (reverseTok) { if (reverseTok->str() == "public:") { virtualDestructorError(base, baseName, derivedClass->str()); break; } else if (reverseTok->str() == "protected:" || reverseTok->str() == "private:") { // No bug, protected/private destructor is allowed break; } else if (reverseTok->str() == "{") { indent++; if (indent >= 1) { // We have found the start of the class without any sign // of "public :" so we can assume that the destructor is not // public and there is no bug in the code we are checking. break; } } else if (reverseTok->str() == "}") indent--; reverseTok = reverseTok->previous(); } } } } //--------------------------------------------------------------------------- void CheckClass::thisSubtractionError(const Token *tok) { reportError(tok, Severity::style, "thisSubtraction", "Suspicious pointer subtraction"); } void CheckClass::thisSubtraction() { if (!_settings->_checkCodingStyle) return; const Token *tok = _tokenizer->tokens(); for (;;) { tok = Token::findmatch(tok, "this - %var%"); if (!tok) break; if (!Token::simpleMatch(tok->previous(), "*")) thisSubtractionError(tok); tok = tok->next(); } } //--------------------------------------------------------------------------- struct NestInfo { std::string className; const Token * classEnd; int levelEnd; }; // Can a function be const? void CheckClass::checkConst() { if (!_settings->_checkCodingStyle) return; std::vector nestInfo; int level = 0; Var *varlist = 0; for (const Token *tok = _tokenizer->tokens(); tok; tok = tok->next()) { if (tok->str() == "{" && !nestInfo.empty()) level++; else if (tok->str() == "}" && !nestInfo.empty()) { level--; if (level == nestInfo.back().levelEnd) nestInfo.pop_back(); } else if (Token::Match(tok, "class|struct %var% {")) { const Token *classTok = tok; // get class name.. std::string classname(tok->strAt(1)); // goto initial {' while (tok && tok->str() != "{") tok = tok->next(); if (!tok) break; const Token *classEnd = tok->link(); NestInfo info; info.className = classname; info.classEnd = classEnd; info.levelEnd = level++; nestInfo.push_back(info); // Delete the varlist.. while (varlist) { Var *nextvar = varlist->next; delete varlist; varlist = nextvar; } // Get class variables... varlist = getVarList(classTok, true, classTok->str() == "struct"); // parse in this class definition to see if there are any simple getter functions for (const Token *tok2 = tok->next(); tok2; tok2 = tok2->next()) { if (tok2->str() == "{") tok2 = tok2->link(); else if (tok2->str() == "}") break; // start of statement? if (!Token::Match(tok2->previous(), "[;{}]")) continue; // skip private: public: etc if (tok2->isName() && tok2->str().find(":") != std::string::npos) { if (tok2->next()->str() == "}") continue; tok2 = tok2->next(); } // static functions can't be const // virtual functions may be non-const for a reason if (Token::Match(tok2, "static|virtual")) continue; // don't warn for unknown types.. // LPVOID, HDC, etc if (tok2->isName()) { bool allupper = true; const std::string s(tok2->str()); for (std::string::size_type pos = 0; pos < s.size(); ++pos) { unsigned char ch = s[pos]; if (!(ch == '_' || (ch >= 'A' && ch <= 'Z'))) { allupper = false; break; } } if (allupper) continue; } // member function? if (isMemberFunc(tok2)) { // goto function name.. while (tok2->next()->str() != "(") tok2 = tok2->next(); // get function name const std::string functionName((tok2->isName() ? "" : "operator") + tok2->str()); // skip constructor if (functionName == classname) continue; // goto the ')' tok2 = tok2->next()->link(); if (!tok2) break; // is this a non-const function that is implemented inline? if (Token::simpleMatch(tok2, ") {")) { const Token *paramEnd = tok2; // if nothing non-const was found. write error.. if (checkConstFunc(classname, varlist, paramEnd)) { for (int i = nestInfo.size() - 2; i >= 0; i--) classname = std::string(nestInfo[i].className + "::" + classname); checkConstError(tok2, classname, functionName); } } else if (Token::simpleMatch(tok2, ") ;")) // not inline { for (int i = nestInfo.size() - 1; i >= 0; i--) { const Token *found = nestInfo[i].classEnd; std::string pattern(functionName + " ("); int namespaceLevel = 0; for (int j = nestInfo.size() - 1; j >= i; j--, namespaceLevel++) pattern = std::string(nestInfo[j].className + " :: " + pattern); while ((found = Token::findmatch(found->next(), pattern.c_str())) != NULL) { const Token *paramEnd = found->tokAt(1 + (2 * namespaceLevel))->link(); if (!paramEnd) break; if (paramEnd->next()->str() != "{") break; if (sameFunc(namespaceLevel, tok2, paramEnd)) { // if nothing non-const was found. write error.. if (checkConstFunc(classname, varlist, paramEnd)) { for (int k = nestInfo.size() - 2; k >= 0; k--) classname = std::string(nestInfo[k].className + "::" + classname); checkConstError2(found, tok2, classname, functionName); } } } } } } } } } // Delete the varlist.. while (varlist) { Var *nextvar = varlist->next; delete varlist; varlist = nextvar; } } bool CheckClass::sameFunc(int nest, const Token *firstEnd, const Token *secondEnd) { // check return type (search backwards until previous statement) const Token * firstStart = firstEnd->link()->tokAt(-2); const Token * secondStart = secondEnd->link()->tokAt((-2 * nest) - 2); bool firstDone = false; bool secondDone = false; while (true) { firstDone = false; secondDone = false; if (!firstStart || Token::Match(firstStart, ";|}|{|public:|protected:|private:")) firstDone = true; if (!secondStart || Token::Match(secondStart, ";|}|{|public:|protected:|private:")) secondDone = true; if (firstDone != secondDone) return false; // both done and match if (firstDone) break; if (secondStart->str() != firstStart->str()) return false; firstStart = firstStart->previous(); secondStart = secondStart->previous(); } // check parameter types (names can be different or missing) firstStart = firstEnd->link()->next(); secondStart = secondEnd->link()->next(); while (true) { firstDone = false; secondDone = false; bool again = true; while (again) { again = false; if (firstStart == firstEnd) firstDone = true; if (secondStart == secondEnd) secondDone = true; // possible difference in number of parameters if (firstDone != secondDone) { // check for missing names if (firstDone) { if (secondStart->varId() != 0) again = true; } else { if (firstStart->varId() != 0) again = true; } if (!again) return false; } // both done and match if (firstDone && !again) return true; if (firstStart->varId() != 0) { // skip variable name firstStart = firstStart->next(); again = true; } if (secondStart->varId() != 0) { // skip variable name secondStart = secondStart->next(); again = true; } } if (firstStart->str() != secondStart->str()) return false; // retry after skipped variable names if (!again) { firstStart = firstStart->next(); secondStart = secondStart->next(); } } return true; } // A const member function can return either a copy of or // a const reference or pointer to something. // Is this a member function with these signatures: // type var ( returns a copy of something // const type var ( returns a const copy of something // const type & var ( returns a const reference to something // const type * var ( returns a const pointer to something // type operator any ( returns a copy of something // const type operator any ( returns a const copy of something // const type & operator any ( returns a const reference to something // const type * operator any ( returns a const pointer to something // Type can be anything from a standard type to a complex template. bool CheckClass::isMemberFunc(const Token *tok) { bool isConst = false; if (tok->str() == "const") { isConst = true; tok = tok->next(); } if (Token::Match(tok, "%type%")) { tok = tok->next(); if (Token::Match(tok, "%var% (")) return true; else if (Token::Match(tok, "operator %any% (")) return true; while (Token::Match(tok, ":: %type%")) tok = tok->tokAt(2); // template with parameter(s)? if (Token::Match(tok, "< %type%")) { unsigned int level = 1; tok = tok->tokAt(2); while (tok) { if (tok->str() == "<") level++; else if (tok->str() == ">") { level--; if (level == 0) { tok = tok->next(); break; } } // check for templates returning pointers or references else if (Token::Match(tok, "*|&")) { int back = -2; if (tok->strAt(back) == "::") back -= 2; if (tok->strAt(back) != "const") { if (!isConst) return false; } } tok = tok->next(); } } // template with default type else if (Token::Match(tok, "< >")) tok = tok->tokAt(2); // operator something else if (Token::Match(tok, "operator %any% (")) return true; if (isConst) { while (Token::Match(tok, "*|&")) { tok = tok->next(); if (tok->str() == "const") tok = tok->next(); } } if (Token::Match(tok, "%var% (")) return true; } return false; } bool CheckClass::isMemberVar(const std::string &classname, const Var *varlist, const Token *tok) { while (tok->previous() && !Token::Match(tok->previous(), "}|{|;|public:|protected:|private:|return|:|?")) { if (Token::Match(tok->previous(), "* this")) return true; tok = tok->previous(); } if (tok->str() == "this") return true; if (Token::Match(tok, "( * %var% ) [")) tok = tok->tokAt(2); // ignore class namespace if (tok->str() == classname && tok->next()->str() == "::") tok = tok->tokAt(2); for (const Var *var = varlist; var; var = var->next) { if (var->name == tok->str()) { return !var->isMutable; } } return false; } bool CheckClass::checkConstFunc(const std::string &classname, const Var *varlist, const Token *tok) { // if the function doesn't have any assignment nor function call, // it can be a const function.. unsigned int indentlevel = 0; bool isconst = true; for (const Token *tok1 = tok; tok1; tok1 = tok1->next()) { if (tok1->str() == "{") ++indentlevel; else if (tok1->str() == "}") { if (indentlevel <= 1) break; --indentlevel; } // assignment.. = += |= .. else if (tok1->str() == "=" || (tok1->str().find("=") == 1 && tok1->str().find_first_of("") == std::string::npos)) { if (isMemberVar(classname, varlist, tok1->previous())) { isconst = false; break; } } // streaming: << else if (tok1->str() == "<<" && isMemberVar(classname, varlist, tok1->previous())) { isconst = false; break; } // increment/decrement (member variable?).. else if (Token::Match(tok1, "++|--")) { isconst = false; break; } // function call.. else if (tok1->str() != "return" && Token::Match(tok1, "%var% (") && tok1->str() != "c_str") { isconst = false; break; } // delete.. else if (tok1->str() == "delete") { isconst = false; break; } } return isconst; } void CheckClass::checkConstError(const Token *tok, const std::string &classname, const std::string &funcname) { reportError(tok, Severity::style, "functionConst", "The function '" + classname + "::" + funcname + "' can be const"); } void CheckClass::checkConstError2(const Token *tok1, const Token *tok2, const std::string &classname, const std::string &funcname) { std::list toks; toks.push_back(tok1); toks.push_back(tok2); reportError(toks, Severity::style, "functionConst", "The function '" + classname + "::" + funcname + "' can be const"); } void CheckClass::noConstructorError(const Token *tok, const std::string &classname, bool isStruct) { reportError(tok, Severity::style, "noConstructor", "The " + std::string(isStruct ? "struct" : "class") + " '" + classname + "' has no constructor. Member variables not initialized."); } void CheckClass::uninitVarError(const Token *tok, const std::string &classname, const std::string &varname) { reportError(tok, Severity::style, "uninitVar", "Member variable not initialized in the constructor '" + classname + "::" + varname + "'"); } void CheckClass::operatorEqVarError(const Token *tok, const std::string &classname, const std::string &varname) { reportError(tok, Severity::style, "operatorEqVarError", "Member variable '" + classname + "::" + varname + "' is not assigned a value in '" + classname + "::operator=" + "'"); } void CheckClass::unusedPrivateFunctionError(const Token *tok, const std::string &classname, const std::string &funcname) { reportError(tok, Severity::style, "unusedPrivateFunction", "Unused private function '" + classname + "::" + funcname + "'"); } void CheckClass::memsetClassError(const Token *tok, const std::string &memfunc) { reportError(tok, Severity::error, "memsetClass", "Using '" + memfunc + "' on class"); } void CheckClass::memsetStructError(const Token *tok, const std::string &memfunc, const std::string &classname) { reportError(tok, Severity::error, "memsetStruct", "Using '" + memfunc + "' on struct that contains a 'std::" + classname + "'"); } void CheckClass::operatorEqReturnError(const Token *tok) { reportError(tok, Severity::style, "operatorEq", "'operator=' should return something"); } void CheckClass::virtualDestructorError(const Token *tok, const std::string &Base, const std::string &Derived) { reportError(tok, Severity::error, "virtualDestructor", "Class " + Base + " which is inherited by class " + Derived + " does not have a virtual destructor"); } void CheckClass::operatorEqRetRefThisError(const Token *tok) { reportError(tok, Severity::style, "operatorEqRetRefThis", "'operator=' should return reference to self"); } void CheckClass::operatorEqToSelfError(const Token *tok) { reportError(tok, Severity::style, "operatorEqToSelf", "'operator=' should check for assignment to self"); }