142 lines
4.9 KiB
C++
142 lines
4.9 KiB
C++
/*
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* Cppcheck - A tool for static C/C++ code analysis
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* Copyright (C) 2007-2017 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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//---------------------------------------------------------------------------
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#ifndef checknullpointerH
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#define checknullpointerH
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//---------------------------------------------------------------------------
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#include "check.h"
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#include "config.h"
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#include "valueflow.h"
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#include <list>
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#include <string>
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class ErrorLogger;
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class Library;
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class Settings;
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class Token;
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class Tokenizer;
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/// @addtogroup Checks
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/// @{
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/** @brief check for null pointer dereferencing */
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class CPPCHECKLIB CheckNullPointer : public Check {
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public:
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/** @brief This constructor is used when registering the CheckNullPointer */
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CheckNullPointer() : Check(myName()) {
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}
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/** @brief This constructor is used when running checks. */
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CheckNullPointer(const Tokenizer *tokenizer, const Settings *settings, ErrorLogger *errorLogger)
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: Check(myName(), tokenizer, settings, errorLogger) {
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}
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/** @brief Run checks against the normal token list */
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void runChecks(const Tokenizer *tokenizer, const Settings *settings, ErrorLogger *errorLogger) override {
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CheckNullPointer checkNullPointer(tokenizer, settings, errorLogger);
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checkNullPointer.nullPointer();
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checkNullPointer.arithmetic();
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}
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/** @brief Run checks against the simplified token list */
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void runSimplifiedChecks(const Tokenizer *tokenizer, const Settings *settings, ErrorLogger *errorLogger) override {
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CheckNullPointer checkNullPointer(tokenizer, settings, errorLogger);
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checkNullPointer.nullConstantDereference();
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}
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/**
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* @brief parse a function call and extract information about variable usage
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* @param tok first token
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* @param var variables that the function read / write.
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* @param library --library files data
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*/
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static void parseFunctionCall(const Token &tok,
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std::list<const Token *> &var,
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const Library *library);
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/**
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* Is there a pointer dereference? Everything that should result in
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* a nullpointer dereference error message will result in a true
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* return value. If it's unknown if the pointer is dereferenced false
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* is returned.
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* @param tok token for the pointer
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* @param unknown it is not known if there is a pointer dereference (could be reported as a debug message)
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* @return true => there is a dereference
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*/
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static bool isPointerDeRef(const Token *tok, bool &unknown);
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/** @brief possible null pointer dereference */
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void nullPointer();
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/** @brief dereferencing null constant (after Tokenizer::simplifyKnownVariables) */
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void nullConstantDereference();
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void nullPointerError(const Token *tok) {
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ValueFlow::Value v(0);
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v.setKnown();
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nullPointerError(tok, "", &v, false);
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}
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void nullPointerError(const Token *tok, const std::string &varname, const ValueFlow::Value* value, bool inconclusive);
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private:
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/** Get error messages. Used by --errorlist */
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void getErrorMessages(ErrorLogger *errorLogger, const Settings *settings) const override {
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CheckNullPointer c(nullptr, settings, errorLogger);
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c.nullPointerError(nullptr, "pointer", nullptr, false);
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c.arithmeticError(nullptr, nullptr);
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}
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/** Name of check */
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static std::string myName() {
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return "Null pointer";
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}
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/** class info in WIKI format. Used by --doc */
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std::string classInfo() const override {
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return "Null pointers\n"
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"- null pointer dereferencing\n"
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"- undefined null pointer arithmetic\n";
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}
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/**
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* @brief Does one part of the check for nullPointer().
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* looping through items in a linked list in a inner loop..
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*/
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void nullPointerLinkedList();
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/**
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* @brief Does one part of the check for nullPointer().
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* Dereferencing a pointer and then checking if it's NULL..
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*/
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void nullPointerByDeRefAndChec();
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/** undefined null pointer arithmetic */
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void arithmetic();
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void arithmeticError(const Token *tok, const ValueFlow::Value *value);
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};
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/// @}
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//---------------------------------------------------------------------------
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#endif // checknullpointerH
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