media/audio/audio_output_dispatcher_impl.cc

   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 #include "media/audio/audio_output_dispatcher_impl.h"
   6
   7 #include <algorithm>
   8
   9 #include "base/bind.h"
  10 #include "base/compiler_specific.h"
  11 #include "base/single_thread_task_runner.h"
  12 #include "base/time/time.h"
  13 #include "media/audio/audio_io.h"
  14 #include "media/audio/audio_output_proxy.h"
  15
  16 namespace media {
  17
  18 AudioOutputDispatcherImpl::AudioOutputDispatcherImpl(
  19     AudioManager* audio_manager,
  20     const AudioParameters& params,
  21     const std::string& output_device_id,
  22     const base::TimeDelta& close_delay)
  23     : AudioOutputDispatcher(audio_manager,
  24                             params,
  25                             output_device_id),
  26       idle_proxies_(0),
  27       close_timer_(FROM_HERE,
  28                    close_delay,
  29                    this,
  30                    &AudioOutputDispatcherImpl::CloseAllIdleStreams),
  31       audio_log_(
  32           audio_manager->CreateAudioLog(AudioLogFactory::AUDIO_OUTPUT_STREAM)),
  33       audio_stream_id_(0) {}
  34
  35 AudioOutputDispatcherImpl::~AudioOutputDispatcherImpl() {
  36   DCHECK_EQ(idle_proxies_, 0u);
  37   DCHECK(proxy_to_physical_map_.empty());
  38   DCHECK(idle_streams_.empty());
  39 }
  40
  41 bool AudioOutputDispatcherImpl::OpenStream() {
  42   DCHECK(task_runner_->BelongsToCurrentThread());
  43
  44   // Ensure that there is at least one open stream.
  45   if (idle_streams_.empty() && !CreateAndOpenStream())
  46     return false;
  47
  48   ++idle_proxies_;
  49   close_timer_.Reset();
  50   return true;
  51 }
  52
  53 bool AudioOutputDispatcherImpl::StartStream(
  54     AudioOutputStream::AudioSourceCallback* callback,
  55     AudioOutputProxy* stream_proxy) {
  56   DCHECK(task_runner_->BelongsToCurrentThread());
  57   DCHECK(proxy_to_physical_map_.find(stream_proxy) ==
  58          proxy_to_physical_map_.end());
  59
  60   if (idle_streams_.empty() && !CreateAndOpenStream())
  61     return false;
  62
  63   AudioOutputStream* physical_stream = idle_streams_.back();
  64   idle_streams_.pop_back();
  65
  66   DCHECK_GT(idle_proxies_, 0u);
  67   --idle_proxies_;
  68
  69   double volume = 0;
  70   stream_proxy->GetVolume(&volume);
  71   physical_stream->SetVolume(volume);
  72   const int stream_id = audio_stream_ids_[physical_stream];
  73   audio_log_->OnSetVolume(stream_id, volume);
  74   physical_stream->Start(callback);
  75   audio_log_->OnStarted(stream_id);
  76   proxy_to_physical_map_[stream_proxy] = physical_stream;
  77
  78   close_timer_.Reset();
  79   return true;
  80 }
  81
  82 void AudioOutputDispatcherImpl::StopStream(AudioOutputProxy* stream_proxy) {
  83   DCHECK(task_runner_->BelongsToCurrentThread());
  84
  85   AudioStreamMap::iterator it = proxy_to_physical_map_.find(stream_proxy);
  86   DCHECK(it != proxy_to_physical_map_.end());
  87   AudioOutputStream* physical_stream = it->second;
  88   proxy_to_physical_map_.erase(it);
  89
  90   physical_stream->Stop();
  91   audio_log_->OnStopped(audio_stream_ids_[physical_stream]);
  92   ++idle_proxies_;
  93   idle_streams_.push_back(physical_stream);
  94
  95   close_timer_.Reset();
  96 }
  97
  98 void AudioOutputDispatcherImpl::StreamVolumeSet(AudioOutputProxy* stream_proxy,
  99                                                 double volume) {
 100   DCHECK(task_runner_->BelongsToCurrentThread());
 101   AudioStreamMap::iterator it = proxy_to_physical_map_.find(stream_proxy);
 102   if (it != proxy_to_physical_map_.end()) {
 103     AudioOutputStream* physical_stream = it->second;
 104     physical_stream->SetVolume(volume);
 105     audio_log_->OnSetVolume(audio_stream_ids_[physical_stream], volume);
 106   }
 107 }
 108
 109 void AudioOutputDispatcherImpl::CloseStream(AudioOutputProxy* stream_proxy) {
 110   DCHECK(task_runner_->BelongsToCurrentThread());
 111
 112   DCHECK_GT(idle_proxies_, 0u);
 113   --idle_proxies_;
 114
 115   // Leave at least a single stream running until the close timer fires to help
 116   // cycle time when streams are opened and closed repeatedly.
 117   CloseIdleStreams(std::max(idle_proxies_, static_cast<size_t>(1)));
 118   close_timer_.Reset();
 119 }
 120
 121 void AudioOutputDispatcherImpl::Shutdown() {
 122   DCHECK(task_runner_->BelongsToCurrentThread());
 123
 124   // Close all idle streams immediately.  The |close_timer_| will handle
 125   // invalidating any outstanding tasks upon its destruction.
 126   CloseAllIdleStreams();
 127
 128   // No AudioOutputProxy objects should hold a reference to us when we get
 129   // to this stage.
 130   DCHECK(HasOneRef()) << "Only the AudioManager should hold a reference";
 131 }
 132
 133 bool AudioOutputDispatcherImpl::HasOutputProxies() const {
 134   return idle_proxies_ || !proxy_to_physical_map_.empty();
 135 }
 136
 137 bool AudioOutputDispatcherImpl::CreateAndOpenStream() {
 138   DCHECK(task_runner_->BelongsToCurrentThread());
 139   AudioOutputStream* stream = audio_manager_->MakeAudioOutputStream(
 140       params_, device_id_);
 141   if (!stream)
 142     return false;
 143
 144   if (!stream->Open()) {
 145     stream->Close();
 146     return false;
 147   }
 148
 149   const int stream_id = audio_stream_id_++;
 150   audio_stream_ids_[stream] = stream_id;
 151   audio_log_->OnCreated(
 152       stream_id, params_, device_id_);
 153
 154   idle_streams_.push_back(stream);
 155   return true;
 156 }
 157
 158 void AudioOutputDispatcherImpl::CloseAllIdleStreams() {
 159   DCHECK(task_runner_->BelongsToCurrentThread());
 160   CloseIdleStreams(0);
 161 }
 162
 163 void AudioOutputDispatcherImpl::CloseIdleStreams(size_t keep_alive) {
 164   DCHECK(task_runner_->BelongsToCurrentThread());
 165   if (idle_streams_.size() <= keep_alive)
 166     return;
 167   for (size_t i = keep_alive; i < idle_streams_.size(); ++i) {
 168     AudioOutputStream* stream = idle_streams_[i];
 169     stream->Close();
 170
 171     AudioStreamIDMap::iterator it = audio_stream_ids_.find(stream);
 172     DCHECK(it != audio_stream_ids_.end());
 173     audio_log_->OnClosed(it->second);
 174     audio_stream_ids_.erase(it);
 175   }
 176   idle_streams_.erase(idle_streams_.begin() + keep_alive, idle_streams_.end());
 177 }
 178
 179 }  // namespace media