15821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// Copyright (c) 2012 The Chromium Authors. All rights reserved. 25821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// Use of this source code is governed by a BSD-style license that can be 35821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// found in the LICENSE file. 45821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 55d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles)#include "media/audio/scoped_task_runner_observer.h" 65821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 75821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#include "base/bind.h" 85821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#include "base/synchronization/waitable_event.h" 95821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 105821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)namespace media { 115821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 125d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles)ScopedTaskRunnerObserver::ScopedTaskRunnerObserver( 135d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) const scoped_refptr<base::SingleThreadTaskRunner>& task_runner) 145d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) : task_runner_(task_runner) { 155821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) ObserveLoopDestruction(true, NULL); 165821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 175821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 185d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles)ScopedTaskRunnerObserver::~ScopedTaskRunnerObserver() { 195821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) ObserveLoopDestruction(false, NULL); 205821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 215821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 225d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles)void ScopedTaskRunnerObserver::ObserveLoopDestruction( 235d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) bool enable, 245d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) base::WaitableEvent* done) { 255821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // Note: |done| may be NULL. 265d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) if (task_runner_->BelongsToCurrentThread()) { 27c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) base::MessageLoop* loop = base::MessageLoop::current(); 285821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if (enable) { 295821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) loop->AddDestructionObserver(this); 305821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } else { 315821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) loop->RemoveDestructionObserver(this); 325821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 335821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } else { 345821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) base::WaitableEvent event(false, false); 355d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) if (task_runner_->PostTask(FROM_HERE, 365d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) base::Bind(&ScopedTaskRunnerObserver::ObserveLoopDestruction, 375821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) base::Unretained(this), enable, &event))) { 385821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) event.Wait(); 395821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } else { 405821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // The message loop's thread has already terminated, so no need to wait. 415821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 425821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 435821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 445821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if (done) 455821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) done->Signal(); 465821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 475821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 485821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} // namespace media. 49