Let default device in PulseAudio be the system default device

media/audio/pulse/pulse_input.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "media/audio/pulse/pulse_input.h"
 
 #include <stdint.h>
 
 #include "base/logging.h"
 #include "media/audio/pulse/audio_manager_pulse.h"
@@ skipping 33 matching lines @@
 
 PulseAudioInputStream::~PulseAudioInputStream() {
   // All internal structures should already have been freed in Close(),
   // which calls AudioManagerPulse::Release which deletes this object.
   DCHECK(!handle_);
 }
 
 bool PulseAudioInputStream::Open() {
   DCHECK(thread_checker_.CalledOnValidThread());
   AutoPulseLock auto_lock(pa_mainloop_);
+  std::string device_name_to_use = device_name_;
+  if (device_name_ == AudioManagerBase::kDefaultDeviceId) {
+    GetSystemDefaultInputDevice();
+    device_name_to_use = default_system_device_name_;
+  }
+
   if (!pulse::CreateInputStream(pa_mainloop_, pa_context_, &handle_, params_,
-                                device_name_, &StreamNotifyCallback, this)) {
+                                device_name_to_use, &StreamNotifyCallback,
+                                this)) {
     return false;
   }
 
   DCHECK(handle_);
 
   return true;
 }
 
 void PulseAudioInputStream::Start(AudioInputCallback* callback) {
   DCHECK(thread_checker_.CalledOnValidThread());
@@ skipping 195 matching lines @@
       reinterpret_cast<PulseAudioInputStream*>(user_data);
 
   if (s && stream->callback_ &&
       pa_stream_get_state(s) == PA_STREAM_FAILED) {
     stream->callback_->OnError(stream);
   }
 
   pa_threaded_mainloop_signal(stream->pa_mainloop_, 0);
 }
 
+// static, used by pa_context_get_server_info.
+void PulseAudioInputStream::GetSystemDefaultInputDeviceCallback(
+    pa_context* context,
+    const pa_server_info* info,
+    void* user_data) {
+  media::PulseAudioInputStream* stream =
+      static_cast<media::PulseAudioInputStream*>(user_data);
+  stream->default_system_device_name_ = info->default_source_name;
+  pa_threaded_mainloop_signal(stream->pa_mainloop_, 0);
+}
+
+void PulseAudioInputStream::GetSystemDefaultInputDevice() {
+  DCHECK(pa_mainloop_);
+  DCHECK(pa_context_);
+  pa_operation* operation = pa_context_get_server_info(
+      pa_context_, PulseAudioInputStream::GetSystemDefaultInputDeviceCallback,
+      this);
+  WaitForOperationCompletion(pa_mainloop_, operation);
+}
+
 void PulseAudioInputStream::ReadData() {
   uint32_t hardware_delay = pulse::GetHardwareLatencyInBytes(
       handle_, params_.sample_rate(), params_.GetBytesPerFrame());
 
   // Update the AGC volume level once every second. Note that,
   // |volume| is also updated each time SetVolume() is called
   // through IPC by the render-side AGC.
   // We disregard the |normalized_volume| from GetAgcVolume()
   // and use the value calculated by |volume_|.
   double normalized_volume = 0.0;
@@ skipping 45 matching lines @@
     return false;
 
   size_t index = pa_stream_get_device_index(handle_);
   pa_operation* operation =
       pa_context_get_source_info_by_index(pa_context_, index, callback, this);
   WaitForOperationCompletion(pa_mainloop_, operation);
   return true;
 }
 
 }  // namespace media