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_SINGLE_THREAD_TASK_RUNNER_H_
6#define BASE_SINGLE_THREAD_TASK_RUNNER_H_
7
8#include "base/base_export.h"
9#include "base/sequenced_task_runner.h"
10
11namespace base {
12
13// A SingleThreadTaskRunner is a SequencedTaskRunner with one more
14// guarantee; namely, that all tasks are run on a single dedicated
15// thread. Most use cases require only a SequencedTaskRunner, unless
16// there is a specific need to run tasks on only a single thread.
17//
18// SingleThreadTaskRunner implementations might:
19// - Post tasks to an existing thread's MessageLoop (see
20// MessageLoop::task_runner()).
21// - Create their own worker thread and MessageLoop to post tasks to.
22// - Add tasks to a FIFO and signal to a non-MessageLoop thread for them to
23// be processed. This allows TaskRunner-oriented code run on threads
24// running other kinds of message loop, e.g. Jingle threads.
25class BASE_EXPORT SingleThreadTaskRunner : public SequencedTaskRunner {
26 public:
27 // A more explicit alias to RunsTasksInCurrentSequence().
28 bool BelongsToCurrentThread() const { return RunsTasksInCurrentSequence(); }
29
30 protected:
31 ~SingleThreadTaskRunner() override = default;
32};
33
34} // namespace base
35
36#endif // BASE_SINGLE_THREAD_TASK_RUNNER_H_
37