media/audio/audio_manager_base.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_manager_base.h"
   6
   7 #include "base/bind.h"
   8 #include "base/bind_helpers.h"
   9 #include "base/command_line.h"
  10 #include "base/message_loop/message_loop_proxy.h"
  11 #include "base/strings/string_number_conversions.h"
  12 #include "base/threading/thread.h"
  13 #include "build/build_config.h"
  14 #include "media/audio/audio_output_dispatcher_impl.h"
  15 #include "media/audio/audio_output_proxy.h"
  16 #include "media/audio/audio_output_resampler.h"
  17 #include "media/audio/fake_audio_input_stream.h"
  18 #include "media/audio/fake_audio_output_stream.h"
  19 #include "media/base/media_switches.h"
  20
  21 namespace media {
  22
  23 static const int kStreamCloseDelaySeconds = 5;
  24
  25 // Default maximum number of output streams that can be open simultaneously
  26 // for all platforms.
  27 static const int kDefaultMaxOutputStreams = 16;
  28
  29 // Default maximum number of input streams that can be open simultaneously
  30 // for all platforms.
  31 static const int kDefaultMaxInputStreams = 16;
  32
  33 static const int kMaxInputChannels = 2;
  34
  35 const char AudioManagerBase::kDefaultDeviceName[] = "Default";
  36 const char AudioManagerBase::kDefaultDeviceId[] = "default";
  37 const char AudioManagerBase::kLoopbackInputDeviceId[] = "loopback";
  38
  39 struct AudioManagerBase::DispatcherParams {
  40   DispatcherParams(const AudioParameters& input,
  41                    const AudioParameters& output,
  42                    const std::string& output_device_id,
  43                    const std::string& input_device_id)
  44       : input_params(input),
  45         output_params(output),
  46         input_device_id(input_device_id),
  47         output_device_id(output_device_id) {}
  48   ~DispatcherParams() {}
  49
  50   const AudioParameters input_params;
  51   const AudioParameters output_params;
  52   const std::string input_device_id;
  53   const std::string output_device_id;
  54   scoped_refptr<AudioOutputDispatcher> dispatcher;
  55
  56  private:
  57   DISALLOW_COPY_AND_ASSIGN(DispatcherParams);
  58 };
  59
  60 class AudioManagerBase::CompareByParams {
  61  public:
  62   explicit CompareByParams(const DispatcherParams* dispatcher)
  63       : dispatcher_(dispatcher) {}
  64   bool operator()(DispatcherParams* dispatcher_in) const {
  65     // We will reuse the existing dispatcher when:
  66     // 1) Unified IO is not used, input_params and output_params of the
  67     //    existing dispatcher are the same as the requested dispatcher.
  68     // 2) Unified IO is used, input_params, output_params and input_device_id
  69     //    of the existing dispatcher are the same as the request dispatcher.
  70     return (dispatcher_->input_params == dispatcher_in->input_params &&
  71             dispatcher_->output_params == dispatcher_in->output_params &&
  72             dispatcher_->output_device_id == dispatcher_in->output_device_id &&
  73             (!dispatcher_->input_params.input_channels() ||
  74              dispatcher_->input_device_id == dispatcher_in->input_device_id));
  75   }
  76
  77  private:
  78   const DispatcherParams* dispatcher_;
  79 };
  80
  81 AudioManagerBase::AudioManagerBase()
  82     : max_num_output_streams_(kDefaultMaxOutputStreams),
  83       max_num_input_streams_(kDefaultMaxInputStreams),
  84       num_output_streams_(0),
  85       num_input_streams_(0),
  86       // TODO(dalecurtis): Switch this to an ObserverListThreadSafe, so we don't
  87       // block the UI thread when swapping devices.
  88       output_listeners_(
  89           ObserverList<AudioDeviceListener>::NOTIFY_EXISTING_ONLY),
  90       audio_thread_(new base::Thread("AudioThread")) {
  91 #if defined(OS_WIN)
  92   audio_thread_->init_com_with_mta(true);
  93 #elif defined(OS_MACOSX)
  94   // CoreAudio calls must occur on the main thread of the process, which in our
  95   // case is sadly the browser UI thread.  Failure to execute calls on the right
  96   // thread leads to crashes and odd behavior.  See http://crbug.com/158170.
  97   // TODO(dalecurtis): We should require the message loop to be passed in.
  98   const CommandLine* cmd_line = CommandLine::ForCurrentProcess();
  99   if (!cmd_line->HasSwitch(switches::kDisableMainThreadAudio) &&
 100       base::MessageLoopProxy::current().get() &&
 101       base::MessageLoop::current()->IsType(base::MessageLoop::TYPE_UI)) {
 102     message_loop_ = base::MessageLoopProxy::current();
 103     return;
 104   }
 105 #endif
 106
 107   CHECK(audio_thread_->Start());
 108   message_loop_ = audio_thread_->message_loop_proxy();
 109 }
 110
 111 AudioManagerBase::~AudioManagerBase() {
 112   // The platform specific AudioManager implementation must have already
 113   // stopped the audio thread. Otherwise, we may destroy audio streams before
 114   // stopping the thread, resulting an unexpected behavior.
 115   // This way we make sure activities of the audio streams are all stopped
 116   // before we destroy them.
 117   CHECK(!audio_thread_.get());
 118   // All the output streams should have been deleted.
 119   DCHECK_EQ(0, num_output_streams_);
 120   // All the input streams should have been deleted.
 121   DCHECK_EQ(0, num_input_streams_);
 122 }
 123
 124 string16 AudioManagerBase::GetAudioInputDeviceModel() {
 125   return string16();
 126 }
 127
 128 scoped_refptr<base::MessageLoopProxy> AudioManagerBase::GetMessageLoop() {
 129   return message_loop_;
 130 }
 131
 132 scoped_refptr<base::MessageLoopProxy> AudioManagerBase::GetWorkerLoop() {
 133   // Lazily start the worker thread.
 134   if (!audio_thread_->IsRunning())
 135     CHECK(audio_thread_->Start());
 136
 137   return audio_thread_->message_loop_proxy();
 138 }
 139
 140 AudioOutputStream* AudioManagerBase::MakeAudioOutputStream(
 141     const AudioParameters& params,
 142     const std::string& device_id,
 143     const std::string& input_device_id) {
 144   // TODO(miu): Fix ~50 call points across several unit test modules to call
 145   // this method on the audio thread, then uncomment the following:
 146   // DCHECK(message_loop_->BelongsToCurrentThread());
 147
 148   if (!params.IsValid()) {
 149     DLOG(ERROR) << "Audio parameters are invalid";
 150     return NULL;
 151   }
 152
 153   // Limit the number of audio streams opened. This is to prevent using
 154   // excessive resources for a large number of audio streams. More
 155   // importantly it prevents instability on certain systems.
 156   // See bug: http://crbug.com/30242.
 157   if (num_output_streams_ >= max_num_output_streams_) {
 158     DLOG(ERROR) << "Number of opened output audio streams "
 159                 << num_output_streams_
 160                 << " exceed the max allowed number "
 161                 << max_num_output_streams_;
 162     return NULL;
 163   }
 164
 165   AudioOutputStream* stream;
 166   switch (params.format()) {
 167     case AudioParameters::AUDIO_PCM_LINEAR:
 168       DCHECK(device_id.empty())
 169           << "AUDIO_PCM_LINEAR supports only the default device.";
 170       stream = MakeLinearOutputStream(params);
 171       break;
 172     case AudioParameters::AUDIO_PCM_LOW_LATENCY:
 173       stream = MakeLowLatencyOutputStream(params, device_id, input_device_id);
 174       break;
 175     case AudioParameters::AUDIO_FAKE:
 176       stream = FakeAudioOutputStream::MakeFakeStream(this, params);
 177       break;
 178     default:
 179       stream = NULL;
 180       break;
 181   }
 182
 183   if (stream) {
 184     ++num_output_streams_;
 185   }
 186
 187   return stream;
 188 }
 189
 190 AudioInputStream* AudioManagerBase::MakeAudioInputStream(
 191     const AudioParameters& params,
 192     const std::string& device_id) {
 193   // TODO(miu): Fix ~20 call points across several unit test modules to call
 194   // this method on the audio thread, then uncomment the following:
 195   // DCHECK(message_loop_->BelongsToCurrentThread());
 196
 197   if (!params.IsValid() || (params.channels() > kMaxInputChannels) ||
 198       device_id.empty()) {
 199     DLOG(ERROR) << "Audio parameters are invalid for device " << device_id;
 200     return NULL;
 201   }
 202
 203   if (num_input_streams_ >= max_num_input_streams_) {
 204     DLOG(ERROR) << "Number of opened input audio streams "
 205                 << num_input_streams_
 206                 << " exceed the max allowed number " << max_num_input_streams_;
 207     return NULL;
 208   }
 209
 210   AudioInputStream* stream;
 211   switch (params.format()) {
 212     case AudioParameters::AUDIO_PCM_LINEAR:
 213       stream = MakeLinearInputStream(params, device_id);
 214       break;
 215     case AudioParameters::AUDIO_PCM_LOW_LATENCY:
 216       stream = MakeLowLatencyInputStream(params, device_id);
 217       break;
 218     case AudioParameters::AUDIO_FAKE:
 219       stream = FakeAudioInputStream::MakeFakeStream(this, params);
 220       break;
 221     default:
 222       stream = NULL;
 223       break;
 224   }
 225
 226   if (stream) {
 227     ++num_input_streams_;
 228   }
 229
 230   return stream;
 231 }
 232
 233 AudioOutputStream* AudioManagerBase::MakeAudioOutputStreamProxy(
 234     const AudioParameters& params,
 235     const std::string& device_id,
 236     const std::string& input_device_id) {
 237   DCHECK(message_loop_->BelongsToCurrentThread());
 238
 239   // If the caller supplied an empty device id to select the default device,
 240   // we fetch the actual device id of the default device so that the lookup
 241   // will find the correct device regardless of whether it was opened as
 242   // "default" or via the specific id.
 243   // NOTE: Implementations that don't yet support opening non-default output
 244   // devices may return an empty string from GetDefaultOutputDeviceID().
 245   std::string output_device_id = device_id.empty() ?
 246       GetDefaultOutputDeviceID() : device_id;
 247
 248   // If we're not using AudioOutputResampler our output parameters are the same
 249   // as our input parameters.
 250   AudioParameters output_params = params;
 251   if (params.format() == AudioParameters::AUDIO_PCM_LOW_LATENCY) {
 252     output_params =
 253         GetPreferredOutputStreamParameters(output_device_id, params);
 254
 255     // Ensure we only pass on valid output parameters.
 256     if (!output_params.IsValid()) {
 257       // We've received invalid audio output parameters, so switch to a mock
 258       // output device based on the input parameters.  This may happen if the OS
 259       // provided us junk values for the hardware configuration.
 260       LOG(ERROR) << "Invalid audio output parameters received; using fake "
 261                  << "audio path. Channels: " << output_params.channels() << ", "
 262                  << "Sample Rate: " << output_params.sample_rate() << ", "
 263                  << "Bits Per Sample: " << output_params.bits_per_sample()
 264                  << ", Frames Per Buffer: "
 265                  << output_params.frames_per_buffer();
 266
 267       // Tell the AudioManager to create a fake output device.
 268       output_params = AudioParameters(
 269           AudioParameters::AUDIO_FAKE, params.channel_layout(),
 270           params.sample_rate(), params.bits_per_sample(),
 271           params.frames_per_buffer());
 272     }
 273   }
 274
 275   DispatcherParams* dispatcher_params =
 276       new DispatcherParams(params, output_params, output_device_id,
 277           input_device_id);
 278
 279   AudioOutputDispatchers::iterator it =
 280       std::find_if(output_dispatchers_.begin(), output_dispatchers_.end(),
 281                    CompareByParams(dispatcher_params));
 282   if (it != output_dispatchers_.end()) {
 283     delete dispatcher_params;
 284     return new AudioOutputProxy((*it)->dispatcher.get());
 285   }
 286
 287   const base::TimeDelta kCloseDelay =
 288       base::TimeDelta::FromSeconds(kStreamCloseDelaySeconds);
 289   scoped_refptr<AudioOutputDispatcher> dispatcher;
 290   if (output_params.format() != AudioParameters::AUDIO_FAKE) {
 291     dispatcher = new AudioOutputResampler(this, params, output_params,
 292                                           output_device_id, input_device_id,
 293                                           kCloseDelay);
 294   } else {
 295     dispatcher = new AudioOutputDispatcherImpl(this, output_params,
 296                                                output_device_id,
 297                                                input_device_id, kCloseDelay);
 298   }
 299
 300   dispatcher_params->dispatcher = dispatcher;
 301   output_dispatchers_.push_back(dispatcher_params);
 302   return new AudioOutputProxy(dispatcher.get());
 303 }
 304
 305 void AudioManagerBase::ShowAudioInputSettings() {
 306 }
 307
 308 void AudioManagerBase::GetAudioInputDeviceNames(
 309     AudioDeviceNames* device_names) {
 310 }
 311
 312 void AudioManagerBase::GetAudioOutputDeviceNames(
 313     AudioDeviceNames* device_names) {
 314 }
 315
 316 void AudioManagerBase::ReleaseOutputStream(AudioOutputStream* stream) {
 317   DCHECK(stream);
 318   // TODO(xians) : Have a clearer destruction path for the AudioOutputStream.
 319   // For example, pass the ownership to AudioManager so it can delete the
 320   // streams.
 321   --num_output_streams_;
 322   delete stream;
 323 }
 324
 325 void AudioManagerBase::ReleaseInputStream(AudioInputStream* stream) {
 326   DCHECK(stream);
 327   // TODO(xians) : Have a clearer destruction path for the AudioInputStream.
 328   --num_input_streams_;
 329   delete stream;
 330 }
 331
 332 void AudioManagerBase::Shutdown() {
 333   // To avoid running into deadlocks while we stop the thread, shut it down
 334   // via a local variable while not holding the audio thread lock.
 335   scoped_ptr<base::Thread> audio_thread;
 336   {
 337     base::AutoLock lock(audio_thread_lock_);
 338     audio_thread_.swap(audio_thread);
 339   }
 340
 341   if (!audio_thread)
 342     return;
 343
 344   // Only true when we're sharing the UI message loop with the browser.  The UI
 345   // loop is no longer running at this time and browser destruction is imminent.
 346   if (message_loop_->BelongsToCurrentThread()) {
 347     ShutdownOnAudioThread();
 348   } else {
 349     message_loop_->PostTask(FROM_HERE, base::Bind(
 350         &AudioManagerBase::ShutdownOnAudioThread, base::Unretained(this)));
 351   }
 352
 353   // Stop() will wait for any posted messages to be processed first.
 354   audio_thread->Stop();
 355 }
 356
 357 void AudioManagerBase::ShutdownOnAudioThread() {
 358   // This should always be running on the audio thread, but since we've cleared
 359   // the audio_thread_ member pointer when we get here, we can't verify exactly
 360   // what thread we're running on.  The method is not public though and only
 361   // called from one place, so we'll leave it at that.
 362   AudioOutputDispatchers::iterator it = output_dispatchers_.begin();
 363   for (; it != output_dispatchers_.end(); ++it) {
 364     scoped_refptr<AudioOutputDispatcher>& dispatcher = (*it)->dispatcher;
 365     if (dispatcher.get()) {
 366       dispatcher->Shutdown();
 367       // All AudioOutputProxies must have been freed before Shutdown is called.
 368       // If they still exist, things will go bad.  They have direct pointers to
 369       // both physical audio stream objects that belong to the dispatcher as
 370       // well as the message loop of the audio thread that will soon go away.
 371       // So, better crash now than later.
 372       DCHECK(dispatcher->HasOneRef()) << "AudioOutputProxies are still alive";
 373       dispatcher = NULL;
 374     }
 375   }
 376
 377   output_dispatchers_.clear();
 378 }
 379
 380 void AudioManagerBase::AddOutputDeviceChangeListener(
 381     AudioDeviceListener* listener) {
 382   DCHECK(message_loop_->BelongsToCurrentThread());
 383   output_listeners_.AddObserver(listener);
 384 }
 385
 386 void AudioManagerBase::RemoveOutputDeviceChangeListener(
 387     AudioDeviceListener* listener) {
 388   DCHECK(message_loop_->BelongsToCurrentThread());
 389   output_listeners_.RemoveObserver(listener);
 390 }
 391
 392 void AudioManagerBase::NotifyAllOutputDeviceChangeListeners() {
 393   DCHECK(message_loop_->BelongsToCurrentThread());
 394   DVLOG(1) << "Firing OnDeviceChange() notifications.";
 395   FOR_EACH_OBSERVER(AudioDeviceListener, output_listeners_, OnDeviceChange());
 396 }
 397
 398 AudioParameters AudioManagerBase::GetDefaultOutputStreamParameters() {
 399   return GetPreferredOutputStreamParameters(GetDefaultOutputDeviceID(),
 400       AudioParameters());
 401 }
 402
 403 AudioParameters AudioManagerBase::GetOutputStreamParameters(
 404     const std::string& device_id) {
 405   return GetPreferredOutputStreamParameters(device_id,
 406       AudioParameters());
 407 }
 408
 409 AudioParameters AudioManagerBase::GetInputStreamParameters(
 410     const std::string& device_id) {
 411   NOTREACHED();
 412   return AudioParameters();
 413 }
 414
 415 std::string AudioManagerBase::GetAssociatedOutputDeviceID(
 416     const std::string& input_device_id) {
 417   NOTIMPLEMENTED();
 418   return "";
 419 }
 420
 421 std::string AudioManagerBase::GetDefaultOutputDeviceID() {
 422   NOTIMPLEMENTED();
 423   return "";
 424 }
 425
 426 int AudioManagerBase::GetUserBufferSize() {
 427   const CommandLine* cmd_line = CommandLine::ForCurrentProcess();
 428   int buffer_size = 0;
 429   std::string buffer_size_str(cmd_line->GetSwitchValueASCII(
 430       switches::kAudioBufferSize));
 431   if (base::StringToInt(buffer_size_str, &buffer_size) && buffer_size > 0)
 432     return buffer_size;
 433
 434   return 0;
 435 }
 436
 437 }  // namespace media