blob: 4b26acf758586f5a275f75013958278d9a26f885 [file] [log] [blame]
// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include <type_traits>
// Include NSObject.h directly because Foundation.h pulls in many dependencies.
// (Approx 100k lines of code versus 1.5k for NSObject.h). scoped_nsobject gets
// singled out because it is most typically included from other header files.
#import <Foundation/NSObject.h>
#include "base/compiler_specific.h"
#include "base/mac/scoped_typeref.h"
@class NSAutoreleasePool;
namespace base {
// scoped_nsobject<> is patterned after std::unique_ptr<>, but maintains
// ownership of an NSObject subclass object. Style deviations here are solely
// for compatibility with std::unique_ptr<>'s interface, with which everyone is
// already familiar.
// scoped_nsobject<> takes ownership of an object (in the constructor or in
// reset()) by taking over the caller's existing ownership claim. The caller
// must own the object it gives to scoped_nsobject<>, and relinquishes an
// ownership claim to that object. scoped_nsobject<> does not call -retain,
// callers have to call this manually if appropriate.
// scoped_nsprotocol<> has the same behavior as scoped_nsobject, but can be used
// with protocols.
// scoped_nsobject<> is not to be used for NSAutoreleasePools. For
// NSAutoreleasePools use ScopedNSAutoreleasePool from
// scoped_nsautorelease_pool.h instead.
// We check for bad uses of scoped_nsobject and NSAutoreleasePool at compile
// time with a template specialization (see below).
namespace internal {
template <typename NST>
struct ScopedNSProtocolTraits {
static NST InvalidValue() { return nil; }
static NST Retain(NST nst) { return [nst retain]; }
static void Release(NST nst) { [nst release]; }
} // namespace internal
template <typename NST>
class scoped_nsprotocol
: public ScopedTypeRef<NST, internal::ScopedNSProtocolTraits<NST>> {
using ScopedTypeRef<NST,
// Shift reference to the autorelease pool to be released later.
NST autorelease() { return [this->release() autorelease]; }
// Free functions
template <class C>
void swap(scoped_nsprotocol<C>& p1, scoped_nsprotocol<C>& p2) {
template <class C>
bool operator==(C p1, const scoped_nsprotocol<C>& p2) {
return p1 == p2.get();
template <class C>
bool operator!=(C p1, const scoped_nsprotocol<C>& p2) {
return p1 != p2.get();
template <typename NST>
class scoped_nsobject : public scoped_nsprotocol<NST*> {
using scoped_nsprotocol<NST*>::scoped_nsprotocol;
static_assert(std::is_same<NST, NSAutoreleasePool>::value == false,
"Use ScopedNSAutoreleasePool instead");
// Specialization to make scoped_nsobject<id> work.
class scoped_nsobject<id> : public scoped_nsprotocol<id> {
using scoped_nsprotocol<id>::scoped_nsprotocol;
} // namespace base