1 // Copyright (c) 2008 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef BASE_FOUNDATION_UTILS_MAC_H_ 6 #define BASE_FOUNDATION_UTILS_MAC_H_ 7 8 #include <CoreFoundation/CoreFoundation.h> 9 #import <Foundation/Foundation.h> 10 11 // CFTypeRefToNSObjectAutorelease transfers ownership of a Core Foundation 12 // object (one derived from CFTypeRef) to the Foundation memory management 13 // system. In a traditional managed-memory environment, cf_object is 14 // autoreleased and returned as an NSObject. In a garbage-collected 15 // environment, cf_object is marked as eligible for garbage collection. 16 // 17 // This function should only be used to convert a concrete CFTypeRef type to 18 // its equivalent "toll-free bridged" NSObject subclass, for example, 19 // converting a CFStringRef to NSString. 20 // 21 // By calling this function, callers relinquish any ownership claim to 22 // cf_object. In a managed-memory environment, the object's ownership will be 23 // managed by the innermost NSAutoreleasePool, so after this function returns, 24 // callers should not assume that cf_object is valid any longer than the 25 // returned NSObject. 26 static inline id CFTypeRefToNSObjectAutorelease(CFTypeRef cf_object) { 27 // When GC is on, NSMakeCollectable marks cf_object for GC and autorelease 28 // is a no-op. 29 // 30 // In the traditional GC-less environment, NSMakeCollectable is a no-op, 31 // and cf_object is autoreleased, balancing out the caller's ownership claim. 32 // 33 // NSMakeCollectable returns nil when used on a NULL object. 34 return [NSMakeCollectable(cf_object) autorelease]; 35 } 36 37 #endif // BASE_FOUNDATION_UTILS_MAC_H_ 38
