chromeos/audio/cras_audio_handler.cc

   1 // Copyright (c) 2013 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 "chromeos/audio/cras_audio_handler.h"
   6
   7 #include <algorithm>
   8 #include <cmath>
   9
  10 #include "base/bind.h"
  11 #include "base/bind_helpers.h"
  12 #include "base/logging.h"
  13 #include "chromeos/audio/audio_devices_pref_handler.h"
  14 #include "chromeos/audio/audio_devices_pref_handler_stub.h"
  15 #include "chromeos/dbus/dbus_thread_manager.h"
  16
  17 using std::max;
  18 using std::min;
  19
  20 namespace chromeos {
  21
  22 namespace {
  23
  24 // Default value for unmuting, as a percent in the range [0, 100].
  25 // Used when sound is unmuted, but volume was less than kMuteThresholdPercent.
  26 const int kDefaultUnmuteVolumePercent = 4;
  27
  28 // Volume value which should be considered as muted in range [0, 100].
  29 const int kMuteThresholdPercent = 1;
  30
  31 static CrasAudioHandler* g_cras_audio_handler = NULL;
  32
  33 bool IsSameAudioDevice(const AudioDevice& a, const AudioDevice& b) {
  34   return a.id == b.id && a.is_input == b.is_input && a.type == b.type
  35       && a.device_name == b.device_name;
  36 }
  37
  38 }  // namespace
  39
  40 CrasAudioHandler::AudioObserver::AudioObserver() {
  41 }
  42
  43 CrasAudioHandler::AudioObserver::~AudioObserver() {
  44 }
  45
  46 void CrasAudioHandler::AudioObserver::OnOutputVolumeChanged() {
  47 }
  48
  49 void CrasAudioHandler::AudioObserver::OnInputGainChanged() {
  50 }
  51
  52 void CrasAudioHandler::AudioObserver::OnOutputMuteChanged() {
  53 }
  54
  55 void CrasAudioHandler::AudioObserver::OnInputMuteChanged() {
  56 }
  57
  58 void CrasAudioHandler::AudioObserver::OnAudioNodesChanged() {
  59 }
  60
  61 void CrasAudioHandler::AudioObserver::OnActiveOutputNodeChanged() {
  62 }
  63
  64 void CrasAudioHandler::AudioObserver::OnActiveInputNodeChanged() {
  65 }
  66
  67 // static
  68 void CrasAudioHandler::Initialize(
  69     scoped_refptr<AudioDevicesPrefHandler> audio_pref_handler) {
  70   CHECK(!g_cras_audio_handler);
  71   g_cras_audio_handler = new CrasAudioHandler(audio_pref_handler);
  72 }
  73
  74 // static
  75 void CrasAudioHandler::InitializeForTesting() {
  76   CHECK(!g_cras_audio_handler);
  77   CrasAudioHandler::Initialize(new AudioDevicesPrefHandlerStub());
  78 }
  79
  80 // static
  81 void CrasAudioHandler::Shutdown() {
  82   CHECK(g_cras_audio_handler);
  83   delete g_cras_audio_handler;
  84   g_cras_audio_handler = NULL;
  85 }
  86
  87 // static
  88 bool CrasAudioHandler::IsInitialized() {
  89   return g_cras_audio_handler != NULL;
  90 }
  91
  92 // static
  93 CrasAudioHandler* CrasAudioHandler::Get() {
  94   CHECK(g_cras_audio_handler)
  95       << "CrasAudioHandler::Get() called before Initialize().";
  96   return g_cras_audio_handler;
  97 }
  98
  99 void CrasAudioHandler::AddAudioObserver(AudioObserver* observer) {
 100   observers_.AddObserver(observer);
 101 }
 102
 103 void CrasAudioHandler::RemoveAudioObserver(AudioObserver* observer) {
 104   observers_.RemoveObserver(observer);
 105 }
 106
 107 bool CrasAudioHandler::IsOutputMuted() {
 108   return output_mute_on_;
 109 }
 110
 111 bool CrasAudioHandler::IsOutputMutedForDevice(uint64 device_id) {
 112   const AudioDevice* device = GetDeviceFromId(device_id);
 113   if (!device)
 114     return false;
 115   DCHECK(!device->is_input);
 116   return audio_pref_handler_->GetMuteValue(*device);
 117 }
 118
 119 bool CrasAudioHandler::IsOutputVolumeBelowDefaultMuteLvel() {
 120   return output_volume_ <= kMuteThresholdPercent;
 121 }
 122
 123 bool CrasAudioHandler::IsInputMuted() {
 124   return input_mute_on_;
 125 }
 126
 127 bool CrasAudioHandler::IsInputMutedForDevice(uint64 device_id) {
 128   const AudioDevice* device = GetDeviceFromId(device_id);
 129   if (!device)
 130     return false;
 131   DCHECK(device->is_input);
 132   // We don't record input mute state for each device in the prefs,
 133   // for any non-active input device, we assume mute is off.
 134   if (device->id == active_input_node_id_)
 135     return input_mute_on_;
 136   return false;
 137 }
 138
 139 int CrasAudioHandler::GetOutputDefaultVolumeMuteThreshold() {
 140   return kMuteThresholdPercent;
 141 }
 142
 143 int CrasAudioHandler::GetOutputVolumePercent() {
 144   return output_volume_;
 145 }
 146
 147 int CrasAudioHandler::GetOutputVolumePercentForDevice(uint64 device_id) {
 148   if (device_id == active_output_node_id_) {
 149     return output_volume_;
 150   } else {
 151     const AudioDevice* device = GetDeviceFromId(device_id);
 152     return static_cast<int>(audio_pref_handler_->GetOutputVolumeValue(device));
 153   }
 154 }
 155
 156 int CrasAudioHandler::GetInputGainPercent() {
 157   return input_gain_;
 158 }
 159
 160 int CrasAudioHandler::GetInputGainPercentForDevice(uint64 device_id) {
 161   if (device_id == active_input_node_id_) {
 162     return input_gain_;
 163   } else {
 164     const AudioDevice* device = GetDeviceFromId(device_id);
 165     return static_cast<int>(audio_pref_handler_->GetInputGainValue(device));
 166   }
 167 }
 168
 169 uint64 CrasAudioHandler::GetActiveOutputNode() const {
 170   return active_output_node_id_;
 171 }
 172
 173 uint64 CrasAudioHandler::GetActiveInputNode() const {
 174   return active_input_node_id_;
 175 }
 176
 177 void CrasAudioHandler::GetAudioDevices(AudioDeviceList* device_list) const {
 178   device_list->clear();
 179   for (AudioDeviceMap::const_iterator it = audio_devices_.begin();
 180        it != audio_devices_.end(); ++it)
 181     device_list->push_back(it->second);
 182 }
 183
 184 bool CrasAudioHandler::GetActiveOutputDevice(AudioDevice* device) const {
 185   const AudioDevice* active_device = GetDeviceFromId(active_output_node_id_);
 186   if (!active_device || !device)
 187     return false;
 188   *device = *active_device;
 189   return true;
 190 }
 191
 192 bool CrasAudioHandler::has_alternative_input() const {
 193   return has_alternative_input_;
 194 }
 195
 196 bool CrasAudioHandler::has_alternative_output() const {
 197   return has_alternative_output_;
 198 }
 199
 200 void CrasAudioHandler::SetOutputVolumePercent(int volume_percent) {
 201   volume_percent = min(max(volume_percent, 0), 100);
 202   if (volume_percent <= kMuteThresholdPercent)
 203     volume_percent = 0;
 204   output_volume_ = volume_percent;
 205
 206   if (const AudioDevice* device = GetDeviceFromId(active_output_node_id_))
 207     audio_pref_handler_->SetVolumeGainValue(*device, output_volume_);
 208
 209   SetOutputNodeVolume(active_output_node_id_, output_volume_);
 210   FOR_EACH_OBSERVER(AudioObserver, observers_, OnOutputVolumeChanged());
 211 }
 212
 213 // TODO: Rename the 'Percent' to something more meaningful.
 214 void CrasAudioHandler::SetInputGainPercent(int gain_percent) {
 215   // NOTE: We do not sanitize input gain values since the range is completely
 216   // dependent on the device.
 217   input_gain_ = gain_percent;
 218
 219   if (const AudioDevice* device = GetDeviceFromId(active_input_node_id_))
 220     audio_pref_handler_->SetVolumeGainValue(*device, input_gain_);
 221
 222   SetInputNodeGain(active_input_node_id_, input_gain_);
 223   FOR_EACH_OBSERVER(AudioObserver, observers_, OnInputGainChanged());
 224 }
 225
 226 void CrasAudioHandler::AdjustOutputVolumeByPercent(int adjust_by_percent) {
 227   SetOutputVolumePercent(output_volume_ + adjust_by_percent);
 228 }
 229
 230 void CrasAudioHandler::SetOutputMute(bool mute_on) {
 231   if (!SetOutputMuteInternal(mute_on))
 232     return;
 233
 234   if (const AudioDevice* device = GetDeviceFromId(active_output_node_id_)) {
 235     DCHECK(!device->is_input);
 236     audio_pref_handler_->SetMuteValue(*device, output_mute_on_);
 237   }
 238
 239   FOR_EACH_OBSERVER(AudioObserver, observers_, OnOutputMuteChanged());
 240 }
 241
 242 void CrasAudioHandler::AdjustOutputVolumeToAudibleLevel() {
 243   if (output_volume_ <= kMuteThresholdPercent) {
 244     // Avoid the situation when sound has been unmuted, but the volume
 245     // is set to a very low value, so user still can't hear any sound.
 246     SetOutputVolumePercent(kDefaultUnmuteVolumePercent);
 247   }
 248 }
 249
 250 void CrasAudioHandler::SetInputMute(bool mute_on) {
 251   if (!SetInputMuteInternal(mute_on))
 252     return;
 253
 254   FOR_EACH_OBSERVER(AudioObserver, observers_, OnInputMuteChanged());
 255 }
 256
 257 void CrasAudioHandler::SetActiveOutputNode(uint64 node_id) {
 258   chromeos::DBusThreadManager::Get()->GetCrasAudioClient()->
 259       SetActiveOutputNode(node_id);
 260   FOR_EACH_OBSERVER(AudioObserver, observers_, OnActiveOutputNodeChanged());
 261 }
 262
 263 void CrasAudioHandler::SetActiveInputNode(uint64 node_id) {
 264   chromeos::DBusThreadManager::Get()->GetCrasAudioClient()->
 265       SetActiveInputNode(node_id);
 266   FOR_EACH_OBSERVER(AudioObserver, observers_, OnActiveInputNodeChanged());
 267 }
 268
 269 void CrasAudioHandler::SetVolumeGainPercentForDevice(uint64 device_id,
 270                                                      int value) {
 271   if (device_id == active_output_node_id_) {
 272     SetOutputVolumePercent(value);
 273     return;
 274   } else if (device_id == active_input_node_id_) {
 275     SetInputGainPercent(value);
 276     return;
 277   }
 278
 279   if (const AudioDevice* device = GetDeviceFromId(device_id)) {
 280     if (!device->is_input) {
 281       value = min(max(value, 0), 100);
 282       if (value <= kMuteThresholdPercent)
 283         value = 0;
 284     }
 285     audio_pref_handler_->SetVolumeGainValue(*device, value);
 286   }
 287 }
 288
 289 void CrasAudioHandler::SetMuteForDevice(uint64 device_id, bool mute_on) {
 290   if (device_id == active_output_node_id_) {
 291     SetOutputMute(mute_on);
 292     return;
 293   } else if (device_id == active_input_node_id_) {
 294     VLOG(1) << "SetMuteForDevice sets active input device id="
 295             << "0x" << std::hex << device_id << " mute=" << mute_on;
 296     SetInputMute(mute_on);
 297     return;
 298   }
 299
 300   const AudioDevice* device = GetDeviceFromId(device_id);
 301   // Input device's mute state is not recorded in the pref. crbug.com/365050.
 302   if (device && !device->is_input)
 303     audio_pref_handler_->SetMuteValue(*device, mute_on);
 304 }
 305
 306 void CrasAudioHandler::LogErrors() {
 307   log_errors_ = true;
 308 }
 309
 310 CrasAudioHandler::CrasAudioHandler(
 311     scoped_refptr<AudioDevicesPrefHandler> audio_pref_handler)
 312     : audio_pref_handler_(audio_pref_handler),
 313       weak_ptr_factory_(this),
 314       output_mute_on_(false),
 315       input_mute_on_(false),
 316       output_volume_(0),
 317       input_gain_(0),
 318       active_output_node_id_(0),
 319       active_input_node_id_(0),
 320       has_alternative_input_(false),
 321       has_alternative_output_(false),
 322       output_mute_locked_(false),
 323       input_mute_locked_(false),
 324       log_errors_(false) {
 325   if (!audio_pref_handler.get())
 326     return;
 327   // If the DBusThreadManager or the CrasAudioClient aren't available, there
 328   // isn't much we can do. This should only happen when running tests.
 329   if (!chromeos::DBusThreadManager::IsInitialized() ||
 330       !chromeos::DBusThreadManager::Get() ||
 331       !chromeos::DBusThreadManager::Get()->GetCrasAudioClient())
 332     return;
 333   chromeos::DBusThreadManager::Get()->GetCrasAudioClient()->AddObserver(this);
 334   audio_pref_handler_->AddAudioPrefObserver(this);
 335   if (chromeos::DBusThreadManager::Get()->GetSessionManagerClient()) {
 336     chromeos::DBusThreadManager::Get()->GetSessionManagerClient()->
 337         AddObserver(this);
 338   }
 339   InitializeAudioState();
 340 }
 341
 342 CrasAudioHandler::~CrasAudioHandler() {
 343   if (!chromeos::DBusThreadManager::IsInitialized() ||
 344       !chromeos::DBusThreadManager::Get() ||
 345       !chromeos::DBusThreadManager::Get()->GetCrasAudioClient())
 346     return;
 347   chromeos::DBusThreadManager::Get()->GetCrasAudioClient()->
 348       RemoveObserver(this);
 349   chromeos::DBusThreadManager::Get()->GetSessionManagerClient()->
 350       RemoveObserver(this);
 351   if (audio_pref_handler_.get())
 352     audio_pref_handler_->RemoveAudioPrefObserver(this);
 353   audio_pref_handler_ = NULL;
 354 }
 355
 356 void CrasAudioHandler::AudioClientRestarted() {
 357   // Make sure the logging is enabled in case cras server
 358   // restarts after crashing.
 359   LogErrors();
 360   InitializeAudioState();
 361 }
 362
 363 void CrasAudioHandler::NodesChanged() {
 364   // Refresh audio nodes data.
 365   GetNodes();
 366 }
 367
 368 void CrasAudioHandler::ActiveOutputNodeChanged(uint64 node_id) {
 369   if (active_output_node_id_ == node_id)
 370     return;
 371
 372   // Active audio output device should always be changed by chrome.
 373   // During system boot, cras may change active input to unknown device 0x1,
 374   // we don't need to log it, since it is not an valid device.
 375   if (GetDeviceFromId(node_id)) {
 376     LOG_IF(WARNING, log_errors_)
 377         << "Active output node changed unexpectedly by system node_id="
 378         << "0x" << std::hex << node_id;
 379   }
 380 }
 381
 382 void CrasAudioHandler::ActiveInputNodeChanged(uint64 node_id) {
 383   if (active_input_node_id_ == node_id)
 384     return;
 385
 386   // Active audio input device should always be changed by chrome.
 387   // During system boot, cras may change active input to unknown device 0x2,
 388   // we don't need to log it, since it is not an valid device.
 389   if (GetDeviceFromId(node_id)) {
 390     LOG_IF(WARNING, log_errors_)
 391         << "Active input node changed unexpectedly by system node_id="
 392         << "0x" << std::hex << node_id;
 393   }
 394 }
 395
 396 void CrasAudioHandler::OnAudioPolicyPrefChanged() {
 397   ApplyAudioPolicy();
 398 }
 399
 400 void CrasAudioHandler::EmitLoginPromptVisibleCalled() {
 401   // Enable logging after cras server is started, which will be after
 402   // EmitLoginPromptVisible.
 403   LogErrors();
 404 }
 405
 406 const AudioDevice* CrasAudioHandler::GetDeviceFromId(uint64 device_id) const {
 407   AudioDeviceMap::const_iterator it = audio_devices_.find(device_id);
 408   if (it == audio_devices_.end())
 409     return NULL;
 410
 411   return &(it->second);
 412 }
 413
 414 void CrasAudioHandler::SetupAudioInputState() {
 415   // Set the initial audio state to the ones read from audio prefs.
 416   const AudioDevice* device = GetDeviceFromId(active_input_node_id_);
 417   if (!device) {
 418     LOG_IF(ERROR, log_errors_)
 419         << "Can't set up audio state for unknown input device id ="
 420         << "0x" << std::hex << active_input_node_id_;
 421     return;
 422   }
 423   input_gain_ = audio_pref_handler_->GetInputGainValue(device);
 424   VLOG(1) << "SetupAudioInputState for active device id="
 425           << "0x" << std::hex << device->id << " mute=" << input_mute_on_;
 426   SetInputMuteInternal(input_mute_on_);
 427   // TODO(rkc,jennyz): Set input gain once we decide on how to store
 428   // the gain values since the range and step are both device specific.
 429 }
 430
 431 void CrasAudioHandler::SetupAudioOutputState() {
 432   const AudioDevice* device = GetDeviceFromId(active_output_node_id_);
 433   if (!device) {
 434     LOG_IF(ERROR, log_errors_)
 435         << "Can't set up audio state for unknown output device id ="
 436         << "0x" << std::hex << active_output_node_id_;
 437     return;
 438   }
 439   DCHECK(!device->is_input);
 440   output_mute_on_ = audio_pref_handler_->GetMuteValue(*device);
 441   output_volume_ = audio_pref_handler_->GetOutputVolumeValue(device);
 442
 443   SetOutputMuteInternal(output_mute_on_);
 444   SetOutputNodeVolume(active_output_node_id_, output_volume_);
 445 }
 446
 447 void CrasAudioHandler::InitializeAudioState() {
 448   ApplyAudioPolicy();
 449   GetNodes();
 450 }
 451
 452 void CrasAudioHandler::ApplyAudioPolicy() {
 453   output_mute_locked_ = false;
 454   if (!audio_pref_handler_->GetAudioOutputAllowedValue()) {
 455     // Mute the device, but do not update the preference.
 456     SetOutputMuteInternal(true);
 457     output_mute_locked_ = true;
 458   } else {
 459     // Restore the mute state.
 460     const AudioDevice* device = GetDeviceFromId(active_output_node_id_);
 461     if (device)
 462       SetOutputMuteInternal(audio_pref_handler_->GetMuteValue(*device));
 463   }
 464
 465   input_mute_locked_ = false;
 466   if (audio_pref_handler_->GetAudioCaptureAllowedValue()) {
 467     VLOG(1) << "Audio input allowed by policy, sets input id="
 468             << "0x" << std::hex << active_input_node_id_ << " mute=false";
 469     SetInputMuteInternal(false);
 470   } else {
 471     VLOG(0) << "Audio input NOT allowed by policy, sets input id="
 472             << "0x" << std::hex << active_input_node_id_ << " mute=true";
 473     SetInputMuteInternal(true);
 474     input_mute_locked_ = true;
 475   }
 476 }
 477
 478 void CrasAudioHandler::SetOutputNodeVolume(uint64 node_id, int volume) {
 479   chromeos::DBusThreadManager::Get()->GetCrasAudioClient()->
 480       SetOutputNodeVolume(node_id, volume);
 481 }
 482
 483 bool  CrasAudioHandler::SetOutputMuteInternal(bool mute_on) {
 484   if (output_mute_locked_)
 485     return false;
 486
 487   output_mute_on_ = mute_on;
 488   chromeos::DBusThreadManager::Get()->GetCrasAudioClient()->
 489       SetOutputUserMute(mute_on);
 490   return true;
 491 }
 492
 493 void CrasAudioHandler::SetInputNodeGain(uint64 node_id, int gain) {
 494   chromeos::DBusThreadManager::Get()->GetCrasAudioClient()->
 495       SetInputNodeGain(node_id, gain);
 496 }
 497
 498 bool CrasAudioHandler::SetInputMuteInternal(bool mute_on) {
 499   if (input_mute_locked_)
 500     return false;
 501
 502   VLOG(1) << "SetInputMuteInternal sets active input device id="
 503           << "0x" << std::hex << active_input_node_id_ << " mute=" << mute_on;
 504   input_mute_on_ = mute_on;
 505   chromeos::DBusThreadManager::Get()->GetCrasAudioClient()->
 506       SetInputMute(mute_on);
 507   return true;
 508 }
 509
 510 void CrasAudioHandler::GetNodes() {
 511   chromeos::DBusThreadManager::Get()->GetCrasAudioClient()->GetNodes(
 512       base::Bind(&CrasAudioHandler::HandleGetNodes,
 513                  weak_ptr_factory_.GetWeakPtr()),
 514       base::Bind(&CrasAudioHandler::HandleGetNodesError,
 515                  weak_ptr_factory_.GetWeakPtr()));
 516 }
 517
 518 bool CrasAudioHandler::ChangeActiveDevice(const AudioDevice& new_active_device,
 519                                           uint64* current_active_node_id) {
 520   // If the device we want to switch to is already the current active device,
 521   // do nothing.
 522   if (new_active_device.active &&
 523       new_active_device.id == *current_active_node_id) {
 524     return false;
 525   }
 526
 527   // Reset all other input or output devices' active status. The active audio
 528   // device from the previous user session can be remembered by cras, but not
 529   // in chrome. see crbug.com/273271.
 530   for (AudioDeviceMap::iterator it = audio_devices_.begin();
 531        it != audio_devices_.end(); ++it) {
 532     if (it->second.is_input == new_active_device.is_input &&
 533         it->second.id != new_active_device.id)
 534       it->second.active = false;
 535   }
 536
 537   // Set the current active input/output device to the new_active_device.
 538   *current_active_node_id = new_active_device.id;
 539   audio_devices_[*current_active_node_id].active = true;
 540   return true;
 541 }
 542
 543 bool CrasAudioHandler::NonActiveDeviceUnplugged(
 544     size_t old_devices_size,
 545     size_t new_devices_size,
 546     uint64 current_active_node) {
 547   return (new_devices_size < old_devices_size &&
 548           GetDeviceFromId(current_active_node));
 549 }
 550
 551 void CrasAudioHandler::SwitchToDevice(const AudioDevice& device) {
 552   if (device.is_input) {
 553     if (!ChangeActiveDevice(device, &active_input_node_id_))
 554       return;
 555     SetupAudioInputState();
 556     SetActiveInputNode(active_input_node_id_);
 557   } else {
 558     if (!ChangeActiveDevice(device, &active_output_node_id_))
 559       return;
 560     SetupAudioOutputState();
 561     SetActiveOutputNode(active_output_node_id_);
 562   }
 563 }
 564
 565 bool CrasAudioHandler::HasDeviceChange(const AudioNodeList& new_nodes,
 566                                        bool is_input) {
 567   size_t num_old_devices = 0;
 568   size_t num_new_devices = 0;
 569   for (AudioDeviceMap::const_iterator it = audio_devices_.begin();
 570        it != audio_devices_.end(); ++it) {
 571     if (is_input == it->second.is_input)
 572       ++num_old_devices;
 573   }
 574
 575   for (AudioNodeList::const_iterator it = new_nodes.begin();
 576        it != new_nodes.end(); ++it) {
 577     if (is_input == it->is_input) {
 578       ++num_new_devices;
 579       // Look to see if the new device not in the old device list.
 580       AudioDevice device(*it);
 581       if (FoundNewDevice(device))
 582         return true;
 583     }
 584   }
 585   return num_old_devices != num_new_devices;
 586 }
 587
 588 bool CrasAudioHandler::FoundNewDevice(const AudioDevice& device) {
 589   const AudioDevice* device_found = GetDeviceFromId(device.id);
 590   if (!device_found)
 591     return true;
 592
 593   if (!IsSameAudioDevice(device, *device_found)) {
 594     LOG(WARNING) << "Different Audio devices with same id:"
 595         << " new device: " << device.ToString()
 596         << " old device: " << device_found->ToString();
 597     return true;
 598   }
 599   return false;
 600 }
 601
 602 // Sanitize the audio node data. When a device is plugged in or unplugged, there
 603 // should be only one NodesChanged signal from cras. However, we've observed
 604 // the case that multiple NodesChanged signals being sent from cras. After the
 605 // first NodesChanged being processed, chrome sets the active node properly.
 606 // However, the NodesChanged received after the first one, can return stale
 607 // nodes data in GetNodes call, the staled nodes data does not reflect the
 608 // latest active node state. Since active audio node should only be set by
 609 // chrome, the inconsistent data from cras could be the result of stale data
 610 // described above and sanitized.
 611 AudioDevice CrasAudioHandler::GetSanitizedAudioDevice(const AudioNode& node) {
 612   AudioDevice device(node);
 613   if (device.is_input) {
 614     if (device.active && device.id != active_input_node_id_) {
 615       LOG(WARNING) << "Stale audio device data, should not be active: "
 616           << " device = " << device.ToString()
 617           << " current active input node id = 0x" << std::hex
 618           << active_input_node_id_;
 619       device.active = false;
 620     } else if (device.id == active_input_node_id_ && !device.active) {
 621       LOG(WARNING) << "Stale audio device data, should be active:"
 622           << " device = " << device.ToString()
 623           << " current active input node id = 0x" << std::hex
 624           << active_input_node_id_;
 625       device.active = true;
 626     }
 627   } else {
 628     if (device.active && device.id != active_output_node_id_) {
 629       LOG(WARNING) << "Stale audio device data, should not be active: "
 630           << " device = " << device.ToString()
 631           << " current active output node id = 0x" << std::hex
 632           << active_output_node_id_;
 633       device.active = false;
 634     } else if (device.id == active_output_node_id_ && !device.active) {
 635       LOG(WARNING) << "Stale audio device data, should be active:"
 636           << " device = " << device.ToString()
 637           << " current active output node id = 0x" << std::hex
 638           << active_output_node_id_;
 639       device.active = true;
 640     }
 641   }
 642   return device;
 643 }
 644
 645 void CrasAudioHandler::UpdateDevicesAndSwitchActive(
 646     const AudioNodeList& nodes) {
 647   size_t old_audio_devices_size = audio_devices_.size();
 648   bool output_devices_changed = HasDeviceChange(nodes, false);
 649   bool input_devices_changed = HasDeviceChange(nodes, true);
 650   audio_devices_.clear();
 651   has_alternative_input_ = false;
 652   has_alternative_output_ = false;
 653
 654   while (!input_devices_pq_.empty())
 655     input_devices_pq_.pop();
 656   while (!output_devices_pq_.empty())
 657     output_devices_pq_.pop();
 658
 659   for (size_t i = 0; i < nodes.size(); ++i) {
 660     AudioDevice device = GetSanitizedAudioDevice(nodes[i]);
 661     audio_devices_[device.id] = device;
 662
 663     if (!has_alternative_input_ &&
 664         device.is_input &&
 665         device.type != AUDIO_TYPE_INTERNAL_MIC) {
 666       has_alternative_input_ = true;
 667     } else if (!has_alternative_output_ &&
 668                !device.is_input &&
 669                device.type != AUDIO_TYPE_INTERNAL_SPEAKER) {
 670       has_alternative_output_ = true;
 671     }
 672
 673     if (device.is_input)
 674       input_devices_pq_.push(device);
 675     else
 676       output_devices_pq_.push(device);
 677   }
 678
 679   // If audio nodes change is caused by unplugging some non-active audio
 680   // devices, the previously set active audio device will stay active.
 681   // Otherwise, switch to a new active audio device according to their priority.
 682   if (input_devices_changed &&
 683       !NonActiveDeviceUnplugged(old_audio_devices_size,
 684                                 audio_devices_.size(),
 685                                 active_input_node_id_) &&
 686       !input_devices_pq_.empty())
 687     SwitchToDevice(input_devices_pq_.top());
 688   if (output_devices_changed &&
 689       !NonActiveDeviceUnplugged(old_audio_devices_size,
 690                                 audio_devices_.size(),
 691                                 active_output_node_id_) &&
 692       !output_devices_pq_.empty()) {
 693     SwitchToDevice(output_devices_pq_.top());
 694   }
 695 }
 696
 697 void CrasAudioHandler::HandleGetNodes(const chromeos::AudioNodeList& node_list,
 698                                       bool success) {
 699   if (!success) {
 700     LOG_IF(ERROR, log_errors_) << "Failed to retrieve audio nodes data";
 701     return;
 702   }
 703
 704   UpdateDevicesAndSwitchActive(node_list);
 705   FOR_EACH_OBSERVER(AudioObserver, observers_, OnAudioNodesChanged());
 706 }
 707
 708 void CrasAudioHandler::HandleGetNodesError(const std::string& error_name,
 709                                            const std::string& error_msg) {
 710   LOG_IF(ERROR, log_errors_) << "Failed to call GetNodes: "
 711       << error_name  << ": " << error_msg;
 712 }
 713 }  // namespace chromeos