145 lines · cpp
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-exception6//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 20using namespace clang;21using namespace ento;22 23bool 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("Ref"))29 return true;30 // XPC unfortunately uses CF-style function names, but aren't CF types.31 if (TDName.starts_with("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-counted49/// type from the DiskArbitration framework.50static bool isDiskArbitrationAPIRefType(QualType T) {51 return cocoa::isRefType(T, "DADisk") ||52 cocoa::isRefType(T, "DADissenter") ||53 cocoa::isRefType(T, "DASessionRef");54}55 56bool coreFoundation::isCFObjectRef(QualType T) {57 return cocoa::isRefType(T, "CF") || // Core Foundation.58 cocoa::isRefType(T, "CG") || // Core Graphics.59 cocoa::isRefType(T, "CM") || // Core Media.60 isDiskArbitrationAPIRefType(T);61}62 63 64bool 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 tracked75 // 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 no85 // @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 96bool 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(*(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 lowercase127 // character.128 StringRef suffix = functionName.substr(it - start);129 if (suffix.starts_with("reate")) {130 it += 5;131 } else if (suffix.starts_with("opy")) {132 it += 3;133 } else {134 // Keep scanning.135 continue;136 }137 138 if (it == endI || !isLowercase(*it))139 return true;140 141 // If we matched a lowercase character, it isn't the end of the142 // word. Keep scanning.143 }144}145