/*
* Cppcheck - A tool for static C/C++ code analysis
* Copyright (C) 2007-2019 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 .
*/
//---------------------------------------------------------------------------
#ifndef astutilsH
#define astutilsH
//---------------------------------------------------------------------------
#include
#include
#include
#include "errorlogger.h"
#include "utils.h"
class Library;
class Settings;
class Scope;
class Token;
class Variable;
enum class ChildrenToVisit {
none,
op1,
op2,
op1_and_op2,
done // found what we looked for, don't visit any more children
};
/**
* Visit AST nodes recursively. The order is not "well defined"
*/
void visitAstNodes(const Token *ast, std::function visitor);
std::vector astFlatten(const Token* tok, const char* op);
/** Is expression a 'signed char' if no promotion is used */
bool astIsSignedChar(const Token *tok);
/** Is expression a 'char' if no promotion is used? */
bool astIsUnknownSignChar(const Token *tok);
/** Is expression of integral type? */
bool astIsIntegral(const Token *tok, bool unknown);
/** Is expression of floating point type? */
bool astIsFloat(const Token *tok, bool unknown);
/** Is expression of boolean type? */
bool astIsBool(const Token *tok);
bool astIsPointer(const Token *tok);
bool astIsIterator(const Token *tok);
bool astIsContainer(const Token *tok);
/**
* Get canonical type of expression. const/static/etc are not included and neither *&.
* For example:
* Expression type Return
* std::string std::string
* int * int
* static const int int
* std::vector std::vector
*/
std::string astCanonicalType(const Token *expr);
/** Is given syntax tree a variable comparison against value */
const Token * astIsVariableComparison(const Token *tok, const std::string &comp, const std::string &rhs, const Token **vartok=nullptr);
const Token * nextAfterAstRightmostLeaf(const Token * tok);
Token* astParentSkipParens(Token* tok);
const Token* astParentSkipParens(const Token* tok);
bool precedes(const Token * tok1, const Token * tok2);
bool isSameExpression(bool cpp, bool macro, const Token *tok1, const Token *tok2, const Library& library, bool pure, bool followVar, ErrorPath* errors=nullptr);
bool isEqualKnownValue(const Token * const tok1, const Token * const tok2);
bool isDifferentKnownValues(const Token * const tok1, const Token * const tok2);
/**
* Are two conditions opposite
* @param isNot do you want to know if cond1 is !cond2 or if cond1 and cond2 are non-overlapping. true: cond1==!cond2 false: cond1==true => cond2==false
* @param cpp c++ file
* @param cond1 condition1
* @param cond2 condition2
* @param library files data
* @param pure boolean
*/
bool isOppositeCond(bool isNot, bool cpp, const Token * const cond1, const Token * const cond2, const Library& library, bool pure, bool followVar, ErrorPath* errors=nullptr);
bool isOppositeExpression(bool cpp, const Token * const tok1, const Token * const tok2, const Library& library, bool pure, bool followVar, ErrorPath* errors=nullptr);
bool isConstExpression(const Token *tok, const Library& library, bool pure, bool cpp);
bool isWithoutSideEffects(bool cpp, const Token* tok);
bool isUniqueExpression(const Token* tok);
/** Is scope a return scope (scope will unconditionally return) */
bool isReturnScope(const Token *endToken, const Settings * settings = nullptr, bool functionScope=false);
/** Is variable changed by function call?
* In case the answer of the question is inconclusive, e.g. because the function declaration is not known
* the return value is false and the output parameter inconclusive is set to true
*
* @param tok ast tree
* @param varid Variable Id
* @param settings program settings
* @param inconclusive pointer to output variable which indicates that the answer of the question is inconclusive
*/
bool isVariableChangedByFunctionCall(const Token *tok, nonneg int varid, const Settings *settings, bool *inconclusive);
/** Is variable changed by function call?
* In case the answer of the question is inconclusive, e.g. because the function declaration is not known
* the return value is false and the output parameter inconclusive is set to true
*
* @param tok token of variable in function call
* @param settings program settings
* @param inconclusive pointer to output variable which indicates that the answer of the question is inconclusive
*/
bool isVariableChangedByFunctionCall(const Token *tok, const Settings *settings, bool *inconclusive);
/** Is variable changed in block of code? */
bool isVariableChanged(const Token *start, const Token *end, const nonneg int varid, bool globalvar, const Settings *settings, bool cpp, int depth = 20);
bool isVariableChanged(const Token *tok, const Settings *settings, bool cpp, int depth = 20);
bool isVariableChanged(const Variable * var, const Settings *settings, bool cpp, int depth = 20);
const Token* findVariableChanged(const Token *start, const Token *end, const nonneg int varid, bool globalvar, const Settings *settings, bool cpp, int depth = 20);
Token* findVariableChanged(Token *start, const Token *end, const nonneg int varid, bool globalvar, const Settings *settings, bool cpp, int depth = 20);
bool isAliased(const Variable *var);
/** Determines the number of arguments - if token is a function call or macro
* @param start token which is supposed to be the function/macro name.
* \return Number of arguments
*/
int numberOfArguments(const Token *start);
/**
* Get arguments (AST)
*/
std::vector getArguments(const Token *ftok);
const Token *findLambdaStartToken(const Token *last);
/**
* find lambda function end token
* \param first The [ token
* \return nullptr or the }
*/
const Token *findLambdaEndToken(const Token *first);
bool isLikelyStream(bool cpp, const Token *stream);
/**
* do we see a likely write of rhs through overloaded operator
* s >> x;
* a & x;
*/
bool isLikelyStreamRead(bool cpp, const Token *op);
bool isCPPCast(const Token* tok);
bool isConstVarExpression(const Token *tok);
const Variable *getLHSVariable(const Token *tok);
struct PathAnalysis {
enum class Progress {
Continue,
Break
};
PathAnalysis(const Token* start, const Library& library)
: start(start), library(&library)
{}
const Token * start;
const Library * library;
struct Info {
const Token* tok;
ErrorPath errorPath;
bool known;
};
void forward(const std::function& f) const;
template
void forwardAll(F f) {
forward([&](const Info& info) {
f(info);
return Progress::Continue;
});
}
template
Info forwardFind(Predicate pred) {
Info result{};
forward([&](const Info& info) {
if (pred(info)) {
result = info;
return Progress::Break;
}
return Progress::Continue;
});
return result;
}
private:
Progress forwardRecursive(const Token* tok, Info info, const std::function& f) const;
Progress forwardRange(const Token* startToken, const Token* endToken, Info info, const std::function& f) const;
static const Scope* findOuterScope(const Scope * scope);
static std::pair checkCond(const Token * tok, bool& known);
};
/**
* @brief Returns true if there is a path between the two tokens
*
* @param start Starting point of the path
* @param dest The path destination
* @param errorPath Adds the path traversal to the errorPath
*/
bool reaches(const Token * start, const Token * dest, const Library& library, ErrorPath* errorPath);
/**
* Forward data flow analysis for checks
* - unused value
* - redundant assignment
* - valueflow analysis
*/
class FwdAnalysis {
public:
FwdAnalysis(bool cpp, const Library &library) : mCpp(cpp), mLibrary(library), mWhat(What::Reassign), mValueFlowKnown(true) {}
bool hasOperand(const Token *tok, const Token *lhs) const;
/**
* Check if "expr" is reassigned. The "expr" can be a tree (x.y[12]).
* @param expr Symbolic expression to perform forward analysis for
* @param startToken First token in forward analysis
* @param endToken Last token in forward analysis
* @return Token where expr is reassigned. If it's not reassigned then nullptr is returned.
*/
const Token *reassign(const Token *expr, const Token *startToken, const Token *endToken);
/**
* Check if "expr" is used. The "expr" can be a tree (x.y[12]).
* @param expr Symbolic expression to perform forward analysis for
* @param startToken First token in forward analysis
* @param endToken Last token in forward analysis
* @return true if expr is used.
*/
bool unusedValue(const Token *expr, const Token *startToken, const Token *endToken);
struct KnownAndToken {
bool known;
const Token *token;
};
std::vector valueFlow(const Token *expr, const Token *startToken, const Token *endToken);
/** Is there some possible alias for given expression */
bool possiblyAliased(const Token *expr, const Token *startToken) const;
static bool isNullOperand(const Token *expr);
private:
static bool isEscapedAlias(const Token* expr);
/** Result of forward analysis */
struct Result {
enum class Type { NONE, READ, WRITE, BREAK, RETURN, BAILOUT } type;
explicit Result(Type type) : type(type), token(nullptr) {}
Result(Type type, const Token *token) : type(type), token(token) {}
const Token *token;
};
struct Result check(const Token *expr, const Token *startToken, const Token *endToken);
struct Result checkRecursive(const Token *expr, const Token *startToken, const Token *endToken, const std::set &exprVarIds, bool local, bool inInnerClass);
// Is expression a l-value global data?
bool isGlobalData(const Token *expr) const;
const bool mCpp;
const Library &mLibrary;
enum class What { Reassign, UnusedValue, ValueFlow } mWhat;
std::vector mValueFlow;
bool mValueFlowKnown;
};
#endif // astutilsH