CocoaConventions.cpp revision 221345 
1//===- CocoaConventions.h - Special handling of Cocoa conventions -*- 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
11//
12//===----------------------------------------------------------------------===//
13
14#include "clang/Analysis/DomainSpecific/CocoaConventions.h"
15#include "clang/AST/Type.h"
16#include "clang/AST/Decl.h"
17#include "clang/AST/DeclObjC.h"
18#include "llvm/ADT/StringExtras.h"
19#include "llvm/Support/ErrorHandling.h"
20
21using namespace clang;
22using namespace ento;
23
24using llvm::StringRef;
25
26// The "fundamental rule" for naming conventions of methods:
27//  (url broken into two lines)
28//  http://developer.apple.com/documentation/Cocoa/Conceptual/
29//     MemoryMgmt/Tasks/MemoryManagementRules.html
30//
31// "You take ownership of an object if you create it using a method whose name
32//  begins with "alloc" or "new" or contains "copy" (for example, alloc,
33//  newObject, or mutableCopy), or if you send it a retain message. You are
34//  responsible for relinquishing ownership of objects you own using release
35//  or autorelease. Any other time you receive an object, you must
36//  not release it."
37//
38
39cocoa::NamingConvention cocoa::deriveNamingConvention(Selector S) {
40  switch (S.getMethodFamily()) {
41  case OMF_None:
42  case OMF_autorelease:
43  case OMF_dealloc:
44  case OMF_release:
45  case OMF_retain:
46  case OMF_retainCount:
47    return NoConvention;
48
49  case OMF_init:
50    return InitRule;
51
52  case OMF_alloc:
53  case OMF_copy:
54  case OMF_mutableCopy:
55  case OMF_new:
56    return CreateRule;
57  }
58  llvm_unreachable("unexpected naming convention");
59  return NoConvention;
60}
61
62bool cocoa::isRefType(QualType RetTy, llvm::StringRef Prefix,
63                      llvm::StringRef Name) {
64  // Recursively walk the typedef stack, allowing typedefs of reference types.
65  while (const TypedefType *TD = dyn_cast<TypedefType>(RetTy.getTypePtr())) {
66    llvm::StringRef TDName = TD->getDecl()->getIdentifier()->getName();
67    if (TDName.startswith(Prefix) && TDName.endswith("Ref"))
68      return true;
69
70    RetTy = TD->getDecl()->getUnderlyingType();
71  }
72
73  if (Name.empty())
74    return false;
75
76  // Is the type void*?
77  const PointerType* PT = RetTy->getAs<PointerType>();
78  if (!(PT->getPointeeType().getUnqualifiedType()->isVoidType()))
79    return false;
80
81  // Does the name start with the prefix?
82  return Name.startswith(Prefix);
83}
84
85bool cocoa::isCFObjectRef(QualType T) {
86  return isRefType(T, "CF") || // Core Foundation.
87         isRefType(T, "CG") || // Core Graphics.
88         isRefType(T, "DADisk") || // Disk Arbitration API.
89         isRefType(T, "DADissenter") ||
90         isRefType(T, "DASessionRef");
91}
92
93
94bool cocoa::isCocoaObjectRef(QualType Ty) {
95  if (!Ty->isObjCObjectPointerType())
96    return false;
97
98  const ObjCObjectPointerType *PT = Ty->getAs<ObjCObjectPointerType>();
99
100  // Can be true for objects with the 'NSObject' attribute.
101  if (!PT)
102    return true;
103
104  // We assume that id<..>, id, Class, and Class<..> all represent tracked
105  // objects.
106  if (PT->isObjCIdType() || PT->isObjCQualifiedIdType() ||
107      PT->isObjCClassType() || PT->isObjCQualifiedClassType())
108    return true;
109
110  // Does the interface subclass NSObject?
111  // FIXME: We can memoize here if this gets too expensive.
112  const ObjCInterfaceDecl *ID = PT->getInterfaceDecl();
113
114  // Assume that anything declared with a forward declaration and no
115  // @interface subclasses NSObject.
116  if (ID->isForwardDecl())
117    return true;
118
119  for ( ; ID ; ID = ID->getSuperClass())
120    if (ID->getIdentifier()->getName() == "NSObject")
121      return true;
122
123  return false;
124}
125