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 11 namespace 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. 25 class BASE_EXPORT SingleThreadTaskRunner : public SequencedTaskRunner { 26 public: 27 // A more explicit alias to RunsTasksInCurrentSequence(). BelongsToCurrentThread()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