1// Copyright (c) 2012 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_MESSAGE_LOOP_MESSAGE_LOOP_PROXY_H_
6#define BASE_MESSAGE_LOOP_MESSAGE_LOOP_PROXY_H_
7
8#include "base/base_export.h"
9#include "base/compiler_specific.h"
10#include "base/memory/ref_counted.h"
11#include "base/single_thread_task_runner.h"
12
13namespace base {
14
15// This class provides a thread-safe refcounted interface to the Post* methods
16// of a message loop. This class can outlive the target message loop.
17// MessageLoopProxy objects are constructed automatically for all MessageLoops.
18// So, to access them, you can use any of the following:
19//   Thread::message_loop_proxy()
20//   MessageLoop::current()->message_loop_proxy()
21//   MessageLoopProxy::current()
22//
23// TODO(akalin): Now that we have the *TaskRunner interfaces, we can
24// merge this with MessageLoopProxyImpl.
25class BASE_EXPORT MessageLoopProxy : public SingleThreadTaskRunner {
26 public:
27  // Gets the MessageLoopProxy for the current message loop, creating one if
28  // needed.
29  static scoped_refptr<MessageLoopProxy> current();
30
31 protected:
32  MessageLoopProxy();
33  virtual ~MessageLoopProxy();
34};
35
36}  // namespace base
37
38#endif  // BASE_MESSAGE_LOOP_MESSAGE_LOOP_PROXY_H_
39