media/audio/alsa/audio_manager_alsa.cc

   1 // Copyright 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 "media/audio/alsa/audio_manager_alsa.h"
   6
   7 #include "base/command_line.h"
   8 #include "base/environment.h"
   9 #include "base/files/file_path.h"
  10 #include "base/logging.h"
  11 #include "base/metrics/histogram.h"
  12 #include "base/nix/xdg_util.h"
  13 #include "base/process/launch.h"
  14 #include "base/stl_util.h"
  15 #include "media/audio/audio_output_dispatcher.h"
  16 #include "media/audio/audio_parameters.h"
  17 #if defined(USE_CRAS)
  18 #include "media/audio/cras/audio_manager_cras.h"
  19 #endif
  20 #include "media/audio/alsa/alsa_input.h"
  21 #include "media/audio/alsa/alsa_output.h"
  22 #include "media/audio/alsa/alsa_wrapper.h"
  23 #if defined(USE_PULSEAUDIO)
  24 #include "media/audio/pulse/audio_manager_pulse.h"
  25 #endif
  26 #include "media/base/channel_layout.h"
  27 #include "media/base/limits.h"
  28 #include "media/base/media_switches.h"
  29
  30 namespace media {
  31
  32 // Maximum number of output streams that can be open simultaneously.
  33 static const int kMaxOutputStreams = 50;
  34
  35 // Default sample rate for input and output streams.
  36 static const int kDefaultSampleRate = 48000;
  37
  38 // Since "default", "pulse" and "dmix" devices are virtual devices mapped to
  39 // real devices, we remove them from the list to avoiding duplicate counting.
  40 // In addition, note that we support no more than 2 channels for recording,
  41 // hence surround devices are not stored in the list.
  42 static const char* kInvalidAudioInputDevices[] = {
  43   "default",
  44   "dmix",
  45   "null",
  46   "pulse",
  47   "surround",
  48 };
  49
  50 // static
  51 void AudioManagerAlsa::ShowLinuxAudioInputSettings() {
  52   scoped_ptr<base::Environment> env(base::Environment::Create());
  53   base::CommandLine command_line(base::CommandLine::NO_PROGRAM);
  54   switch (base::nix::GetDesktopEnvironment(env.get())) {
  55     case base::nix::DESKTOP_ENVIRONMENT_GNOME:
  56       command_line.SetProgram(base::FilePath("gnome-volume-control"));
  57       break;
  58     case base::nix::DESKTOP_ENVIRONMENT_KDE3:
  59     case base::nix::DESKTOP_ENVIRONMENT_KDE4:
  60       command_line.SetProgram(base::FilePath("kmix"));
  61       break;
  62     case base::nix::DESKTOP_ENVIRONMENT_UNITY:
  63       command_line.SetProgram(base::FilePath("gnome-control-center"));
  64       command_line.AppendArg("sound");
  65       command_line.AppendArg("input");
  66       break;
  67     default:
  68       LOG(ERROR) << "Failed to show audio input settings: we don't know "
  69                  << "what command to use for your desktop environment.";
  70       return;
  71   }
  72   base::LaunchProcess(command_line, base::LaunchOptions());
  73 }
  74
  75 // Implementation of AudioManager.
  76 bool AudioManagerAlsa::HasAudioOutputDevices() {
  77   return HasAnyAlsaAudioDevice(kStreamPlayback);
  78 }
  79
  80 bool AudioManagerAlsa::HasAudioInputDevices() {
  81   return HasAnyAlsaAudioDevice(kStreamCapture);
  82 }
  83
  84 AudioManagerAlsa::AudioManagerAlsa(AudioLogFactory* audio_log_factory)
  85     : AudioManagerBase(audio_log_factory),
  86       wrapper_(new AlsaWrapper()) {
  87   SetMaxOutputStreamsAllowed(kMaxOutputStreams);
  88 }
  89
  90 AudioManagerAlsa::~AudioManagerAlsa() {
  91   Shutdown();
  92 }
  93
  94 void AudioManagerAlsa::ShowAudioInputSettings() {
  95   ShowLinuxAudioInputSettings();
  96 }
  97
  98 void AudioManagerAlsa::GetAudioInputDeviceNames(
  99     AudioDeviceNames* device_names) {
 100   DCHECK(device_names->empty());
 101   GetAlsaAudioDevices(kStreamCapture, device_names);
 102 }
 103
 104 void AudioManagerAlsa::GetAudioOutputDeviceNames(
 105     AudioDeviceNames* device_names) {
 106   DCHECK(device_names->empty());
 107   GetAlsaAudioDevices(kStreamPlayback, device_names);
 108 }
 109
 110 AudioParameters AudioManagerAlsa::GetInputStreamParameters(
 111     const std::string& device_id) {
 112   static const int kDefaultInputBufferSize = 1024;
 113
 114   return AudioParameters(
 115       AudioParameters::AUDIO_PCM_LOW_LATENCY, CHANNEL_LAYOUT_STEREO,
 116       kDefaultSampleRate, 16, kDefaultInputBufferSize);
 117 }
 118
 119 void AudioManagerAlsa::GetAlsaAudioDevices(
 120     StreamType type,
 121     media::AudioDeviceNames* device_names) {
 122   // Constants specified by the ALSA API for device hints.
 123   static const char kPcmInterfaceName[] = "pcm";
 124   int card = -1;
 125
 126   // Loop through the sound cards to get ALSA device hints.
 127   while (!wrapper_->CardNext(&card) && card >= 0) {
 128     void** hints = NULL;
 129     int error = wrapper_->DeviceNameHint(card, kPcmInterfaceName, &hints);
 130     if (!error) {
 131       GetAlsaDevicesInfo(type, hints, device_names);
 132
 133       // Destroy the hints now that we're done with it.
 134       wrapper_->DeviceNameFreeHint(hints);
 135     } else {
 136       DLOG(WARNING) << "GetAlsaAudioDevices: unable to get device hints: "
 137                     << wrapper_->StrError(error);
 138     }
 139   }
 140 }
 141
 142 void AudioManagerAlsa::GetAlsaDevicesInfo(
 143     AudioManagerAlsa::StreamType type,
 144     void** hints,
 145     media::AudioDeviceNames* device_names) {
 146   static const char kIoHintName[] = "IOID";
 147   static const char kNameHintName[] = "NAME";
 148   static const char kDescriptionHintName[] = "DESC";
 149
 150   const char* unwanted_device_type = UnwantedDeviceTypeWhenEnumerating(type);
 151
 152   for (void** hint_iter = hints; *hint_iter != NULL; hint_iter++) {
 153     // Only examine devices of the right type.  Valid values are
 154     // "Input", "Output", and NULL which means both input and output.
 155     scoped_ptr<char, base::FreeDeleter> io(wrapper_->DeviceNameGetHint(
 156         *hint_iter, kIoHintName));
 157     if (io != NULL && strcmp(unwanted_device_type, io.get()) == 0)
 158       continue;
 159
 160     // Found a device, prepend the default device since we always want
 161     // it to be on the top of the list for all platforms. And there is
 162     // no duplicate counting here since it is only done if the list is
 163     // still empty.  Note, pulse has exclusively opened the default
 164     // device, so we must open the device via the "default" moniker.
 165     if (device_names->empty()) {
 166       device_names->push_front(media::AudioDeviceName(
 167           AudioManagerBase::kDefaultDeviceName,
 168           AudioManagerBase::kDefaultDeviceId));
 169     }
 170
 171     // Get the unique device name for the device.
 172     scoped_ptr<char, base::FreeDeleter> unique_device_name(
 173         wrapper_->DeviceNameGetHint(*hint_iter, kNameHintName));
 174
 175     // Find out if the device is available.
 176     if (IsAlsaDeviceAvailable(type, unique_device_name.get())) {
 177       // Get the description for the device.
 178       scoped_ptr<char, base::FreeDeleter> desc(wrapper_->DeviceNameGetHint(
 179           *hint_iter, kDescriptionHintName));
 180
 181       media::AudioDeviceName name;
 182       name.unique_id = unique_device_name.get();
 183       if (desc) {
 184         // Use the more user friendly description as name.
 185         // Replace '\n' with '-'.
 186         char* pret = strchr(desc.get(), '\n');
 187         if (pret)
 188           *pret = '-';
 189         name.device_name = desc.get();
 190       } else {
 191         // Virtual devices don't necessarily have descriptions.
 192         // Use their names instead.
 193         name.device_name = unique_device_name.get();
 194       }
 195
 196       // Store the device information.
 197       device_names->push_back(name);
 198     }
 199   }
 200 }
 201
 202 // static
 203 bool AudioManagerAlsa::IsAlsaDeviceAvailable(
 204     AudioManagerAlsa::StreamType type,
 205     const char* device_name) {
 206   if (!device_name)
 207     return false;
 208
 209   // We do prefix matches on the device name to see whether to include
 210   // it or not.
 211   if (type == kStreamCapture) {
 212     // Check if the device is in the list of invalid devices.
 213     for (size_t i = 0; i < arraysize(kInvalidAudioInputDevices); ++i) {
 214       if (strncmp(kInvalidAudioInputDevices[i], device_name,
 215                   strlen(kInvalidAudioInputDevices[i])) == 0)
 216         return false;
 217     }
 218     return true;
 219   } else {
 220     DCHECK_EQ(kStreamPlayback, type);
 221     // We prefer the device type that maps straight to hardware but
 222     // goes through software conversion if needed (e.g. incompatible
 223     // sample rate).
 224     // TODO(joi): Should we prefer "hw" instead?
 225     static const char kDeviceTypeDesired[] = "plughw";
 226     return strncmp(kDeviceTypeDesired,
 227                    device_name,
 228                    arraysize(kDeviceTypeDesired) - 1) == 0;
 229   }
 230 }
 231
 232 // static
 233 const char* AudioManagerAlsa::UnwantedDeviceTypeWhenEnumerating(
 234     AudioManagerAlsa::StreamType wanted_type) {
 235   return wanted_type == kStreamPlayback ? "Input" : "Output";
 236 }
 237
 238 bool AudioManagerAlsa::HasAnyAlsaAudioDevice(
 239     AudioManagerAlsa::StreamType stream) {
 240   static const char kPcmInterfaceName[] = "pcm";
 241   static const char kIoHintName[] = "IOID";
 242   void** hints = NULL;
 243   bool has_device = false;
 244   int card = -1;
 245
 246   // Loop through the sound cards.
 247   // Don't use snd_device_name_hint(-1,..) since there is a access violation
 248   // inside this ALSA API with libasound.so.2.0.0.
 249   while (!wrapper_->CardNext(&card) && (card >= 0) && !has_device) {
 250     int error = wrapper_->DeviceNameHint(card, kPcmInterfaceName, &hints);
 251     if (!error) {
 252       for (void** hint_iter = hints; *hint_iter != NULL; hint_iter++) {
 253         // Only examine devices that are |stream| capable.  Valid values are
 254         // "Input", "Output", and NULL which means both input and output.
 255         scoped_ptr<char, base::FreeDeleter> io(wrapper_->DeviceNameGetHint(
 256             *hint_iter, kIoHintName));
 257         const char* unwanted_type = UnwantedDeviceTypeWhenEnumerating(stream);
 258         if (io != NULL && strcmp(unwanted_type, io.get()) == 0)
 259           continue;  // Wrong type, skip the device.
 260
 261         // Found an input device.
 262         has_device = true;
 263         break;
 264       }
 265
 266       // Destroy the hints now that we're done with it.
 267       wrapper_->DeviceNameFreeHint(hints);
 268       hints = NULL;
 269     } else {
 270       DLOG(WARNING) << "HasAnyAudioDevice: unable to get device hints: "
 271                     << wrapper_->StrError(error);
 272     }
 273   }
 274
 275   return has_device;
 276 }
 277
 278 AudioOutputStream* AudioManagerAlsa::MakeLinearOutputStream(
 279     const AudioParameters& params) {
 280   DCHECK_EQ(AudioParameters::AUDIO_PCM_LINEAR, params.format());
 281   return MakeOutputStream(params);
 282 }
 283
 284 AudioOutputStream* AudioManagerAlsa::MakeLowLatencyOutputStream(
 285     const AudioParameters& params,
 286     const std::string& device_id) {
 287   DLOG_IF(ERROR, !device_id.empty()) << "Not implemented!";
 288   DCHECK_EQ(AudioParameters::AUDIO_PCM_LOW_LATENCY, params.format());
 289   return MakeOutputStream(params);
 290 }
 291
 292 AudioInputStream* AudioManagerAlsa::MakeLinearInputStream(
 293     const AudioParameters& params, const std::string& device_id) {
 294   DCHECK_EQ(AudioParameters::AUDIO_PCM_LINEAR, params.format());
 295   return MakeInputStream(params, device_id);
 296 }
 297
 298 AudioInputStream* AudioManagerAlsa::MakeLowLatencyInputStream(
 299     const AudioParameters& params, const std::string& device_id) {
 300   DCHECK_EQ(AudioParameters::AUDIO_PCM_LOW_LATENCY, params.format());
 301   return MakeInputStream(params, device_id);
 302 }
 303
 304 AudioParameters AudioManagerAlsa::GetPreferredOutputStreamParameters(
 305     const std::string& output_device_id,
 306     const AudioParameters& input_params) {
 307   // TODO(tommi): Support |output_device_id|.
 308   DLOG_IF(ERROR, !output_device_id.empty()) << "Not implemented!";
 309   static const int kDefaultOutputBufferSize = 2048;
 310   ChannelLayout channel_layout = CHANNEL_LAYOUT_STEREO;
 311   int sample_rate = kDefaultSampleRate;
 312   int buffer_size = kDefaultOutputBufferSize;
 313   int bits_per_sample = 16;
 314   if (input_params.IsValid()) {
 315     // Some clients, such as WebRTC, have a more limited use case and work
 316     // acceptably with a smaller buffer size.  The check below allows clients
 317     // which want to try a smaller buffer size on Linux to do so.
 318     // TODO(dalecurtis): This should include bits per channel and channel layout
 319     // eventually.
 320     sample_rate = input_params.sample_rate();
 321     bits_per_sample = input_params.bits_per_sample();
 322     channel_layout = input_params.channel_layout();
 323     buffer_size = std::min(input_params.frames_per_buffer(), buffer_size);
 324   }
 325
 326   int user_buffer_size = GetUserBufferSize();
 327   if (user_buffer_size)
 328     buffer_size = user_buffer_size;
 329
 330   return AudioParameters(
 331       AudioParameters::AUDIO_PCM_LOW_LATENCY, channel_layout,
 332       sample_rate, bits_per_sample, buffer_size, AudioParameters::NO_EFFECTS);
 333 }
 334
 335 AudioOutputStream* AudioManagerAlsa::MakeOutputStream(
 336     const AudioParameters& params) {
 337   std::string device_name = AlsaPcmOutputStream::kAutoSelectDevice;
 338   if (base::CommandLine::ForCurrentProcess()->HasSwitch(
 339           switches::kAlsaOutputDevice)) {
 340     device_name = base::CommandLine::ForCurrentProcess()->GetSwitchValueASCII(
 341         switches::kAlsaOutputDevice);
 342   }
 343   return new AlsaPcmOutputStream(device_name, params, wrapper_.get(), this);
 344 }
 345
 346 AudioInputStream* AudioManagerAlsa::MakeInputStream(
 347     const AudioParameters& params, const std::string& device_id) {
 348   std::string device_name = (device_id == AudioManagerBase::kDefaultDeviceId) ?
 349       AlsaPcmInputStream::kAutoSelectDevice : device_id;
 350   if (base::CommandLine::ForCurrentProcess()->HasSwitch(
 351           switches::kAlsaInputDevice)) {
 352     device_name = base::CommandLine::ForCurrentProcess()->GetSwitchValueASCII(
 353         switches::kAlsaInputDevice);
 354   }
 355
 356   return new AlsaPcmInputStream(this, device_name, params, wrapper_.get());
 357 }
 358
 359 }  // namespace media