NSAutoreleasePoolChecker.cpp revision 45d9b4e44154939b91d6b8f63e7756feaca547f2 
1//=- NSAutoreleasePoolChecker.cpp --------------------------------*- C++ -*-==//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10//  This file defines a NSAutoreleasePoolChecker, a small checker that warns
11//  about subpar uses of NSAutoreleasePool.  Note that while the check itself
12//  (in it's current form) could be written as a flow-insensitive check, in
13//  can be potentially enhanced in the future with flow-sensitive information.
14//  It is also a good example of the CheckerVisitor interface.
15//
16//===----------------------------------------------------------------------===//
17
18#include "ClangSACheckers.h"
19#include "clang/StaticAnalyzer/Core/CheckerV2.h"
20#include "clang/StaticAnalyzer/Core/CheckerManager.h"
21#include "clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h"
22#include "clang/StaticAnalyzer/Core/BugReporter/BugReporter.h"
23#include "clang/StaticAnalyzer/Core/PathSensitive/ExprEngine.h"
24#include "clang/AST/DeclObjC.h"
25#include "clang/AST/Decl.h"
26
27using namespace clang;
28using namespace ento;
29
30namespace {
31class NSAutoreleasePoolChecker
32  : public CheckerV2<check::PreObjCMessage> {
33
34  mutable Selector releaseS;
35
36public:
37  void checkPreObjCMessage(ObjCMessage msg, CheckerContext &C) const;
38};
39
40} // end anonymous namespace
41
42void NSAutoreleasePoolChecker::checkPreObjCMessage(ObjCMessage msg,
43                                                   CheckerContext &C) const {
44
45  const Expr *receiver = msg.getInstanceReceiver();
46  if (!receiver)
47    return;
48
49  // FIXME: Enhance with value-tracking information instead of consulting
50  // the type of the expression.
51  const ObjCObjectPointerType* PT =
52    receiver->getType()->getAs<ObjCObjectPointerType>();
53
54  if (!PT)
55    return;
56  const ObjCInterfaceDecl* OD = PT->getInterfaceDecl();
57  if (!OD)
58    return;
59  if (!OD->getIdentifier()->getName().equals("NSAutoreleasePool"))
60    return;
61
62  if (releaseS.isNull())
63    releaseS = GetNullarySelector("release", C.getASTContext());
64  // Sending 'release' message?
65  if (msg.getSelector() != releaseS)
66    return;
67
68  SourceRange R = msg.getSourceRange();
69
70  C.getBugReporter().EmitBasicReport("Use -drain instead of -release",
71    "API Upgrade (Apple)",
72    "Use -drain instead of -release when using NSAutoreleasePool "
73    "and garbage collection", R.getBegin(), &R, 1);
74}
75
76void ento::registerNSAutoreleasePoolChecker(CheckerManager &mgr) {
77  if (mgr.getLangOptions().getGCMode() != LangOptions::NonGC)
78    mgr.registerChecker<NSAutoreleasePoolChecker>();
79}
80