path: root/src/Utils.h

/*
   This file is part of the clazy static checker.

  Copyright (C) 2015 Klarälvdalens Datakonsult AB, a KDAB Group company, info@kdab.com
  Author: Sérgio Martins <sergio.martins@kdab.com>

  Copyright (C) 2015-2016 Sergio Martins <smartins@kde.org>

  This library is free software; you can redistribute it and/or
  modify it under the terms of the GNU Library General Public
  License as published by the Free Software Foundation; either
  version 2 of the License, or (at your option) any later version.

  This library 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
  Library General Public License for more details.

  You should have received a copy of the GNU Library General Public License
  along with this library; see the file COPYING.LIB.  If not, write to
  the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  Boston, MA 02110-1301, USA.
*/

#ifndef MOREWARNINGS_UTILS_H
#define MOREWARNINGS_UTILS_H

#include "clazy_export.h"
#include "SourceCompatibilityHelpers.h"

#include <clang/Basic/SourceManager.h>
#include <clang/AST/DeclCXX.h>
#include <clang/AST/Expr.h>
#include <clang/AST/ExprCXX.h>
#include <clang/AST/Stmt.h>
#include <clang/AST/DeclTemplate.h>

#include <string>
#include <vector>
#include <map>

// TODO: this is a dumping ground, most of these functions should be moved to the other *Utils classes

namespace clang {
    class CXXNamedCastExpr;
    class CXXRecordDecl;
    class CXXMemberCallExpr;
    class CXXConstructExpr;
    class CompilerInstance;
    class ClassTemplateSpecializationDecl;
    class Decl;
    class ParentMap;
    class SourceManager;
    class Stmt;
    class SourceLocation;
    class ExprWithCleanups;
    class ValueDecl;
    class ConditionalOperator;
    class CXXMethodDecl;
    class BinaryOperator;
}

struct StmtBodyRange;

namespace Utils {
    /// Returns true if the class has at least one constexpr ctor
    CLAZYLIB_EXPORT bool hasConstexprCtor(clang::CXXRecordDecl *decl);

    /// Returns the type we're casting *from*
    CLAZYLIB_EXPORT clang::CXXRecordDecl * namedCastInnerDecl(clang::CXXNamedCastExpr *staticOrDynamicCast);

    /// Returns the type we're casting *to*
    CLAZYLIB_EXPORT clang::CXXRecordDecl * namedCastOuterDecl(clang::CXXNamedCastExpr *staticOrDynamicCast);

    /// Returns the class declaration from a variable declaration
    // So, if the var decl is "Foo f"; it returns the declaration of Foo
    CLAZYLIB_EXPORT clang::CXXRecordDecl * recordFromVarDecl(clang::Decl *);

    /// Returns the template specialization from a variable declaration
    // So, if the var decl is "QList<Foo> f;", returns the template specialization QList<Foo>
    CLAZYLIB_EXPORT clang::ClassTemplateSpecializationDecl * templateSpecializationFromVarDecl(clang::Decl *);

    /// Returns true if all the child member function calls are const functions.
    CLAZYLIB_EXPORT bool allChildrenMemberCallsConst(clang::Stmt *stm);

    /// Returns true if at least a UnaryOperator, BinaryOperator or non-const function call is found
    CLAZYLIB_EXPORT bool childsHaveSideEffects(clang::Stmt *stm);

    /// Receives a member call, such as "list.reserve()" and returns the declaration of the variable list
    // such as "QList<F> list"
    CLAZYLIB_EXPORT clang::ValueDecl * valueDeclForMemberCall(clang::CXXMemberCallExpr *);

    /// Receives an operator call, such as "list << fooo" and returns the declaration of the variable list
    // such as "QList<F> list"
    CLAZYLIB_EXPORT clang::ValueDecl * valueDeclForOperatorCall(clang::CXXOperatorCallExpr *);

    // overload
    CLAZYLIB_EXPORT clang::ValueDecl * valueDeclForCallExpr(clang::CallExpr *);

    // Returns true of this value decl is a member variable of a class or struct
    // returns null if not
    CLAZYLIB_EXPORT clang::CXXRecordDecl* isMemberVariable(clang::ValueDecl *);

    // Returns true if a body of statements contains a non const member call on object declared by varDecl
    // For example:
    // Foo foo; // this is the varDecl
    // while (bar) { foo.setValue(); // non-const call }
    CLAZYLIB_EXPORT bool containsNonConstMemberCall(clang::ParentMap *map, clang::Stmt *body, const clang::VarDecl *varDecl);

    // Returns true if there's an assignment to varDecl in body
    // Example: our_var = something_else
    CLAZYLIB_EXPORT bool isAssignedTo(clang::Stmt *body, const clang::VarDecl *varDecl);

    // Returns true if a body of statements contains a function call that takes our variable (varDecl)
    // By ref or pointer
    CLAZYLIB_EXPORT bool isPassedToFunction(const StmtBodyRange &bodyRange, const clang::VarDecl *varDecl,
                                            bool byRefOrPtrOnly);

    // Returns true if we take the address of varDecl, such as: &foo
    CLAZYLIB_EXPORT bool addressIsTaken(const clang::CompilerInstance &ci, clang::Stmt *body,
                                        const clang::ValueDecl *valDecl);

    // QString::fromLatin1("foo")    -> true
    // QString::fromLatin1("foo", 1) -> false
    CLAZYLIB_EXPORT bool callHasDefaultArguments(clang::CallExpr *expr);

    // If there's a child of type StringLiteral, returns true
    // if allowEmpty is false, "" will be ignored
    CLAZYLIB_EXPORT bool containsStringLiteral(clang::Stmt *, bool allowEmpty = true, int depth = -1);

    CLAZYLIB_EXPORT bool isInsideOperatorCall(clang::ParentMap *map, clang::Stmt *s,
                                              const std::vector<llvm::StringRef> &anyOf);

    CLAZYLIB_EXPORT bool insideCTORCall(clang::ParentMap *map, clang::Stmt *s,
                                        const std::vector<llvm::StringRef> &anyOf);

    // returns true if the ternary operator has two string literal arguments, such as:
    // foo ? "bar" : "baz"
    CLAZYLIB_EXPORT bool ternaryOperatorIsOfStringLiteral(clang::ConditionalOperator*);

    CLAZYLIB_EXPORT bool isAssignOperator(clang::CXXOperatorCallExpr *op,
                                          llvm::StringRef className,
                                          llvm::StringRef argumentType, const clang::LangOptions &lo);

    CLAZYLIB_EXPORT bool isImplicitCastTo(clang::Stmt *, const std::string &);

    CLAZYLIB_EXPORT bool presumedLocationsEqual(const clang::PresumedLoc &l1, const clang::PresumedLoc &l2);


    // Returns the list of methods with name methodName that the class/struct record contains
    CLAZYLIB_EXPORT std::vector<clang::CXXMethodDecl*> methodsFromString(const clang::CXXRecordDecl *record,
                                                                         const std::string &methodName);

    // Returns the most derived class. (CXXMemberCallExpr::getRecordDecl() return the first base class with the method)
    // The returned callee is the name of the variable on which the member call was made:
    // o1->foo() => "o1"
    // foo() => "this"
    CLAZYLIB_EXPORT const clang::CXXRecordDecl* recordForMemberCall(clang::CXXMemberCallExpr *call,
                                                                    std::string &implicitCallee);

    CLAZYLIB_EXPORT bool isAscii(clang::StringLiteral *lt);

    // Checks if Statement s inside an operator* call
    CLAZYLIB_EXPORT bool isInDerefExpression(clang::Stmt *s, clang::ParentMap *map);

    // For a a chain called expression like foo().bar().baz() returns a list of calls
    // {baz(), bar(), foo()}

    // the parameter lastCallExpr to pass would be baz()
    // No need to specify the other callexprs, they are children of the first one, since the AST looks like:
    // - baz
    // -- bar
    // --- foo
    CLAZYLIB_EXPORT std::vector<clang::CallExpr *> callListForChain(clang::CallExpr *lastCallExpr);

    // Returns the first base class
    CLAZYLIB_EXPORT clang::CXXRecordDecl * rootBaseClass(clang::CXXRecordDecl *derived);

    // Returns the copy ctor for this class
    CLAZYLIB_EXPORT clang::CXXConstructorDecl *copyCtor(clang::CXXRecordDecl *);

    // Returns the copy-assignment operator for this class
    CLAZYLIB_EXPORT clang::CXXMethodDecl *copyAssign(clang::CXXRecordDecl *);

    CLAZYLIB_EXPORT bool hasMember(clang::CXXRecordDecl *record, const std::string &memberTypeName);

    /**
     * Returns true if record is a shared pointer (boost, Qt or stl only).
     */
    CLAZYLIB_EXPORT bool isSharedPointer(clang::CXXRecordDecl *record);

    /**
     * Returns true if varDecl is initialized externally.
     * Example:
     *     QList<Foo> list = getList(); // true
     *     QList<int> list = list2;     // true
     *     QList<int> list = {1, 2, 3}; // false
     *     QList<int> list;             // false
     */
    CLAZYLIB_EXPORT bool isInitializedExternally(clang::VarDecl *varDecl);

    /**
     * Returns true if declStmt refers to varDecl
     */
    CLAZYLIB_EXPORT bool referencesVarDecl(clang::DeclStmt *declStmt, clang::VarDecl *varDecl);

    /**
     * Returns true if the body of a function is empty.
     * Returns false if either function or it's body are null.
     */
    CLAZYLIB_EXPORT bool functionHasEmptyBody(clang::FunctionDecl *func);

    /**
     * If stm is an UnaryOperator or BinaryOperator that writes to the variable it returns the expression
     * that represents the variable (Usually a MemberExpr or DeclRefExpr for local variables).
     *
     * Otherwise returns nullptr.
     *
     * The operators that write to the variable are operator=, operator+=, operator++, etc.
     */
    CLAZYLIB_EXPORT clang::Expr* isWriteOperator(clang::Stmt *stm);

    /**
     * Gets the UserDefinedLiteral of type @p type which is somewhere in the ast of @p stm.
     * Returns nullptr if there's no such UserDefinedLiteral.
     */
    CLAZYLIB_EXPORT clang::UserDefinedLiteral* userDefinedLiteral(clang::Stmt *stm, const std::string &type,
                                                                  const clang::LangOptions &lo);

    /**
     * Returns the function parameters fom @p func
     * This should be used instead of calling FunctionDecl::params() since it changed signature in
     * clang 3.9.
     */
    CLAZYLIB_EXPORT
#if LLVM_VERSION_MAJOR == 3 && LLVM_VERSION_MINOR <= 8
    clang::FunctionDecl::param_range
#else
    clang::ArrayRef<clang::ParmVarDecl *>
#endif
    functionParameters(clang::FunctionDecl *func);


    /**
     * For the given ctor, and ctor param, returns the ctor member initializers that used that param.
     * Example:
     * MyCtor(int a, int b) : c(a), d(b) {}
     * auto result = Utils::ctorInitializer(MyCtor, b); // Result is the statement "d(b)"
     */
    CLAZYLIB_EXPORT std::vector<clang::CXXCtorInitializer*> ctorInitializer(clang::CXXConstructorDecl *ctor,
                                                                            clang::ParmVarDecl *param);

   /**
    * Returns true if a ctor initializer contains a std::move()
    * Example
    * MyCtor(Foo a) : c(move(a)) {} // Would return true for this init list
    */
    CLAZYLIB_EXPORT bool ctorInitializerContainsMove(clang::CXXCtorInitializer*);

    // Overload that recieves a vector and returns true if any ctor initializer contains a move()
    CLAZYLIB_EXPORT bool ctorInitializerContainsMove(const std::vector<clang::CXXCtorInitializer*> &);

    /**
     * Returns the filename for the source location loc
     */
    CLAZYLIB_EXPORT std::string filenameForLoc(clang::SourceLocation loc, const clang::SourceManager &sm);

    /**
     * Returns the location after the lexer token that is at loc.
     * For example:
     *     emit sig();
     * If loc refers to the location of 'emit', then this function will return the source location if
     * the sig() call.
     */
    CLAZYLIB_EXPORT clang::SourceLocation locForNextToken(clang::SourceLocation loc,
                                                          const clang::SourceManager &sm,
                                                          const clang::LangOptions &lo);

    inline bool isMainFile(const clang::SourceManager &sm, clang::SourceLocation loc)
    {
        if (loc.isMacroID())
            loc = sm.getExpansionLoc(loc);

        return sm.isInFileID(loc, sm.getMainFileID());
    }

    /**
     * Returns true if the string literal contains escaped bytes, such as \x12, \123, \u00F6.
     */
    bool literalContainsEscapedBytes(clang::StringLiteral *lt, const clang::SourceManager &sm, const clang::LangOptions &lo);

    /**
     * Returns true if this method overrides one from the base class
     */
    inline bool methodOverrides(clang::CXXMethodDecl *method)
    {
        return method && method->isVirtual() && method->size_overridden_methods() > 0;
    }
}

#endif