1 | //===- CocoaConventions.h - Special handling of Cocoa conventions -*- C++ -*--// |
2 | // |
3 | // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
4 | // See https://llvm.org/LICENSE.txt for license information. |
5 | // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
6 | // |
7 | //===----------------------------------------------------------------------===// |
8 | // |
9 | // This file implements cocoa naming convention analysis. |
10 | // |
11 | //===----------------------------------------------------------------------===// |
12 | |
13 | #include "clang/Analysis/DomainSpecific/CocoaConventions.h" |
14 | #include "clang/AST/Decl.h" |
15 | #include "clang/AST/DeclObjC.h" |
16 | #include "clang/AST/Type.h" |
17 | #include "clang/Basic/CharInfo.h" |
18 | #include "llvm/Support/ErrorHandling.h" |
19 | |
20 | using namespace clang; |
21 | using namespace ento; |
22 | |
23 | bool cocoa::isRefType(QualType RetTy, StringRef Prefix, |
24 | StringRef Name) { |
25 | // Recursively walk the typedef stack, allowing typedefs of reference types. |
26 | while (const TypedefType *TD = RetTy->getAs<TypedefType>()) { |
27 | StringRef TDName = TD->getDecl()->getIdentifier()->getName(); |
28 | if (TDName.starts_with(Prefix) && TDName.ends_with(Suffix: "Ref" )) |
29 | return true; |
30 | // XPC unfortunately uses CF-style function names, but aren't CF types. |
31 | if (TDName.starts_with(Prefix: "xpc_" )) |
32 | return false; |
33 | RetTy = TD->getDecl()->getUnderlyingType(); |
34 | } |
35 | |
36 | if (Name.empty()) |
37 | return false; |
38 | |
39 | // Is the type void*? |
40 | const PointerType* PT = RetTy->castAs<PointerType>(); |
41 | if (!PT || !PT->getPointeeType().getUnqualifiedType()->isVoidType()) |
42 | return false; |
43 | |
44 | // Does the name start with the prefix? |
45 | return Name.starts_with(Prefix); |
46 | } |
47 | |
48 | /// Returns true when the passed-in type is a CF-style reference-counted |
49 | /// type from the DiskArbitration framework. |
50 | static bool isDiskArbitrationAPIRefType(QualType T) { |
51 | return cocoa::isRefType(RetTy: T, Prefix: "DADisk" ) || |
52 | cocoa::isRefType(RetTy: T, Prefix: "DADissenter" ) || |
53 | cocoa::isRefType(RetTy: T, Prefix: "DASessionRef" ); |
54 | } |
55 | |
56 | bool coreFoundation::isCFObjectRef(QualType T) { |
57 | return cocoa::isRefType(RetTy: T, Prefix: "CF" ) || // Core Foundation. |
58 | cocoa::isRefType(RetTy: T, Prefix: "CG" ) || // Core Graphics. |
59 | cocoa::isRefType(RetTy: T, Prefix: "CM" ) || // Core Media. |
60 | isDiskArbitrationAPIRefType(T); |
61 | } |
62 | |
63 | |
64 | bool cocoa::isCocoaObjectRef(QualType Ty) { |
65 | if (!Ty->isObjCObjectPointerType()) |
66 | return false; |
67 | |
68 | const ObjCObjectPointerType *PT = Ty->getAs<ObjCObjectPointerType>(); |
69 | |
70 | // Can be true for objects with the 'NSObject' attribute. |
71 | if (!PT) |
72 | return true; |
73 | |
74 | // We assume that id<..>, id, Class, and Class<..> all represent tracked |
75 | // objects. |
76 | if (PT->isObjCIdType() || PT->isObjCQualifiedIdType() || |
77 | PT->isObjCClassType() || PT->isObjCQualifiedClassType()) |
78 | return true; |
79 | |
80 | // Does the interface subclass NSObject? |
81 | // FIXME: We can memoize here if this gets too expensive. |
82 | const ObjCInterfaceDecl *ID = PT->getInterfaceDecl(); |
83 | |
84 | // Assume that anything declared with a forward declaration and no |
85 | // @interface subclasses NSObject. |
86 | if (!ID->hasDefinition()) |
87 | return true; |
88 | |
89 | for ( ; ID ; ID = ID->getSuperClass()) |
90 | if (ID->getIdentifier()->getName() == "NSObject" ) |
91 | return true; |
92 | |
93 | return false; |
94 | } |
95 | |
96 | bool coreFoundation::followsCreateRule(const FunctionDecl *fn) { |
97 | // For now, *just* base this on the function name, not on anything else. |
98 | |
99 | const IdentifierInfo *ident = fn->getIdentifier(); |
100 | if (!ident) return false; |
101 | StringRef functionName = ident->getName(); |
102 | |
103 | StringRef::iterator it = functionName.begin(); |
104 | StringRef::iterator start = it; |
105 | StringRef::iterator endI = functionName.end(); |
106 | |
107 | while (true) { |
108 | // Scan for the start of 'create' or 'copy'. |
109 | for ( ; it != endI ; ++it) { |
110 | // Search for the first character. It can either be 'C' or 'c'. |
111 | char ch = *it; |
112 | if (ch == 'C' || ch == 'c') { |
113 | // Make sure this isn't something like 'recreate' or 'Scopy'. |
114 | if (ch == 'c' && it != start && isLetter(c: *(it - 1))) |
115 | continue; |
116 | |
117 | ++it; |
118 | break; |
119 | } |
120 | } |
121 | |
122 | // Did we hit the end of the string? If so, we didn't find a match. |
123 | if (it == endI) |
124 | return false; |
125 | |
126 | // Scan for *lowercase* 'reate' or 'opy', followed by no lowercase |
127 | // character. |
128 | StringRef suffix = functionName.substr(Start: it - start); |
129 | if (suffix.starts_with(Prefix: "reate" )) { |
130 | it += 5; |
131 | } else if (suffix.starts_with(Prefix: "opy" )) { |
132 | it += 3; |
133 | } else { |
134 | // Keep scanning. |
135 | continue; |
136 | } |
137 | |
138 | if (it == endI || !isLowercase(c: *it)) |
139 | return true; |
140 | |
141 | // If we matched a lowercase character, it isn't the end of the |
142 | // word. Keep scanning. |
143 | } |
144 | } |
145 | |