llvm/clang/lib/StaticAnalyzer/Checkers/NumberObjectConversionChecker.cpp

//===- NumberObjectConversionChecker.cpp -------------------------*- C++ -*-==//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file defines NumberObjectConversionChecker, which checks for a
// particular common mistake when dealing with numbers represented as objects
// passed around by pointers. Namely, the language allows to reinterpret the
// pointer as a number directly, often without throwing any warnings,
// but in most cases the result of such conversion is clearly unexpected,
// as pointer value, rather than number value represented by the pointee object,
// becomes the result of such operation.
//
// Currently the checker supports the Objective-C NSNumber class,
// and the OSBoolean class found in macOS low-level code; the latter
// can only hold boolean values.
//
// This checker has an option "Pedantic" (boolean), which enables detection of
// more conversion patterns (which are most likely more harmless, and therefore
// are more likely to produce false positives) - disabled by default,
// enabled with `-analyzer-config osx.NumberObjectConversion:Pedantic=true'.
//
//===----------------------------------------------------------------------===//

#include "clang/StaticAnalyzer/Checkers/BuiltinCheckerRegistration.h"
#include "clang/ASTMatchers/ASTMatchFinder.h"
#include "clang/StaticAnalyzer/Core/BugReporter/BugReporter.h"
#include "clang/StaticAnalyzer/Core/BugReporter/BugType.h"
#include "clang/StaticAnalyzer/Core/Checker.h"
#include "clang/StaticAnalyzer/Core/PathSensitive/AnalysisManager.h"
#include "clang/Lex/Lexer.h"
#include "llvm/ADT/APSInt.h"

usingnamespaceclang;
usingnamespaceento;
usingnamespaceast_matchers;

namespace {

class NumberObjectConversionChecker : public Checker<check::ASTCodeBody> { … };

class Callback : public MatchFinder::MatchCallback { … };
} // end of anonymous namespace

void Callback::run(const MatchFinder::MatchResult &Result) { … }

void NumberObjectConversionChecker::checkASTCodeBody(const Decl *D,
                                                     AnalysisManager &AM,
                                                     BugReporter &BR) const { … }

void ento::registerNumberObjectConversionChecker(CheckerManager &Mgr) { … }

bool ento::shouldRegisterNumberObjectConversionChecker(const CheckerManager &mgr) { … }