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#pragma once 8 9#include <CoreFoundation/CoreFoundation.h> 10#import <Foundation/Foundation.h> 11 12// CFTypeRefToNSObjectAutorelease transfers ownership of a Core Foundation 13// object (one derived from CFTypeRef) to the Foundation memory management 14// system. In a traditional managed-memory environment, cf_object is 15// autoreleased and returned as an NSObject. In a garbage-collected 16// environment, cf_object is marked as eligible for garbage collection. 17// 18// This function should only be used to convert a concrete CFTypeRef type to 19// its equivalent "toll-free bridged" NSObject subclass, for example, 20// converting a CFStringRef to NSString. 21// 22// By calling this function, callers relinquish any ownership claim to 23// cf_object. In a managed-memory environment, the object's ownership will be 24// managed by the innermost NSAutoreleasePool, so after this function returns, 25// callers should not assume that cf_object is valid any longer than the 26// returned NSObject. 27static inline id CFTypeRefToNSObjectAutorelease(CFTypeRef cf_object) { 28 // When GC is on, NSMakeCollectable marks cf_object for GC and autorelease 29 // is a no-op. 30 // 31 // In the traditional GC-less environment, NSMakeCollectable is a no-op, 32 // and cf_object is autoreleased, balancing out the caller's ownership claim. 33 // 34 // NSMakeCollectable returns nil when used on a NULL object. 35 return [NSMakeCollectable(cf_object) autorelease]; 36} 37 38#endif // BASE_FOUNDATION_UTILS_MAC_H_ 39