Pass task runners to AudioManager constructor.

media/audio/pulse/audio_manager_pulse.cc

 // Copyright 2013 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/audio_manager_pulse.h"
 
 #include "base/command_line.h"
 #include "base/environment.h"
 #include "base/files/file_path.h"
 #include "base/logging.h"
@@ skipping 29 matching lines @@
 static const int kMaximumOutputBufferSize = 8192;
 
 // Default input buffer size.
 static const int kDefaultInputBufferSize = 1024;
 
 #if defined(DLOPEN_PULSEAUDIO)
 static const base::FilePath::CharType kPulseLib[] =
     FILE_PATH_LITERAL("libpulse.so.0");
 #endif
 
-// static
-AudioManager* AudioManagerPulse::Create(AudioLogFactory* audio_log_factory) {
-  scoped_ptr<AudioManagerPulse> ret(new AudioManagerPulse(audio_log_factory));
-  if (ret->Init())
-    return ret.release();
-
-  DVLOG(1) << "PulseAudio is not available on the OS";
-  return NULL;
-}
-
-AudioManagerPulse::AudioManagerPulse(AudioLogFactory* audio_log_factory)
-    : AudioManagerBase(audio_log_factory),
+AudioManagerPulse::AudioManagerPulse(
+    scoped_refptr<base::SingleThreadTaskRunner> task_runner,
+    scoped_refptr<base::SingleThreadTaskRunner> worker_task_runner,
+    AudioLogFactory* audio_log_factory)
+    : AudioManagerBase(std::move(task_runner),
+                       std::move(worker_task_runner),
+                       audio_log_factory),
       input_mainloop_(NULL),
       input_context_(NULL),
       devices_(NULL),
       native_input_sample_rate_(0) {
   SetMaxOutputStreamsAllowed(kMaxOutputStreams);
 }
 
 AudioManagerPulse::~AudioManagerPulse() {
   Shutdown();
 
   // The Pulse objects are the last things to be destroyed since Shutdown()
   // needs them.
   DestroyPulse();

[alokp, 2016/04/05 23:57:40]

I think we need to Shutdown AudioManagerBase, which releases all output stream
dispatchers before we can destroy pulse.

[DaleCurtis, 2016/04/06 01:22:29]

Can we just post a task to a static DestroyPulse method on the current thread?

[alokp, 2016/04/06 02:03:44]

Yup.. thats exactly what I am doing..

 }
 
+bool AudioManagerPulse::Init() {
+  DCHECK(!input_mainloop_);
+
+#if defined(DLOPEN_PULSEAUDIO)
+  StubPathMap paths;
+
+  // Check if the pulse library is avialbale.
+  paths[kModulePulse].push_back(kPulseLib);
+  if (!InitializeStubs(paths)) {
+    VLOG(1) << "Failed on loading the Pulse library and symbols";
+    return false;
+  }
+#endif  // defined(DLOPEN_PULSEAUDIO)
+
+  // Create a mainloop API and connect to the default server.
+  // The mainloop is the internal asynchronous API event loop.
+  input_mainloop_ = pa_threaded_mainloop_new();
+  if (!input_mainloop_)
+    return false;
+
+  // Start the threaded mainloop.
+  if (pa_threaded_mainloop_start(input_mainloop_))
+    return false;
+
+  // Lock the event loop object, effectively blocking the event loop thread
+  // from processing events. This is necessary.
+  AutoPulseLock auto_lock(input_mainloop_);
+
+  pa_mainloop_api* pa_mainloop_api =
+      pa_threaded_mainloop_get_api(input_mainloop_);
+  input_context_ = pa_context_new(pa_mainloop_api, "Chrome input");
+  if (!input_context_)
+    return false;
+
+  pa_context_set_state_callback(input_context_, &pulse::ContextStateCallback,
+                                input_mainloop_);
+  if (pa_context_connect(input_context_, NULL, PA_CONTEXT_NOAUTOSPAWN, NULL)) {
+    VLOG(1) << "Failed to connect to the context.  Error: "
+            << pa_strerror(pa_context_errno(input_context_));
+    return false;
+  }
+
+  // Wait until |input_context_| is ready.  pa_threaded_mainloop_wait() must be
+  // called after pa_context_get_state() in case the context is already ready,
+  // otherwise pa_threaded_mainloop_wait() will hang indefinitely.
+  while (true) {
+    pa_context_state_t context_state = pa_context_get_state(input_context_);
+    if (!PA_CONTEXT_IS_GOOD(context_state))
+      return false;
+    if (context_state == PA_CONTEXT_READY)
+      break;
+    pa_threaded_mainloop_wait(input_mainloop_);
+  }
+
+  return true;
+}
+
 // Implementation of AudioManager.
 bool AudioManagerPulse::HasAudioOutputDevices() {
   AudioDeviceNames devices;
   GetAudioOutputDeviceNames(&devices);
   return !devices.empty();
 }
 
 bool AudioManagerPulse::HasAudioInputDevices() {
   AudioDeviceNames devices;
   GetAudioInputDeviceNames(&devices);
@@ skipping 123 matching lines @@
   DCHECK(input_mainloop_);
   DCHECK(input_context_);
   AutoPulseLock auto_lock(input_mainloop_);
   pa_operation* operation = pa_context_get_server_info(
       input_context_, SampleRateInfoCallback, this);
   WaitForOperationCompletion(input_mainloop_, operation);
 
   return native_input_sample_rate_;
 }
 
-bool AudioManagerPulse::Init() {
-  DCHECK(!input_mainloop_);
-
-#if defined(DLOPEN_PULSEAUDIO)
-  StubPathMap paths;
-
-  // Check if the pulse library is avialbale.
-  paths[kModulePulse].push_back(kPulseLib);
-  if (!InitializeStubs(paths)) {
-    VLOG(1) << "Failed on loading the Pulse library and symbols";
-    return false;
-  }
-#endif  // defined(DLOPEN_PULSEAUDIO)
-
-  // Create a mainloop API and connect to the default server.
-  // The mainloop is the internal asynchronous API event loop.
-  input_mainloop_ = pa_threaded_mainloop_new();
-  if (!input_mainloop_)
-    return false;
-
-  // Start the threaded mainloop.
-  if (pa_threaded_mainloop_start(input_mainloop_))
-    return false;
-
-  // Lock the event loop object, effectively blocking the event loop thread
-  // from processing events. This is necessary.
-  AutoPulseLock auto_lock(input_mainloop_);
-
-  pa_mainloop_api* pa_mainloop_api =
-      pa_threaded_mainloop_get_api(input_mainloop_);
-  input_context_ = pa_context_new(pa_mainloop_api, "Chrome input");
-  if (!input_context_)
-    return false;
-
-  pa_context_set_state_callback(input_context_, &pulse::ContextStateCallback,
-                                input_mainloop_);
-  if (pa_context_connect(input_context_, NULL, PA_CONTEXT_NOAUTOSPAWN, NULL)) {
-    VLOG(1) << "Failed to connect to the context.  Error: "
-            << pa_strerror(pa_context_errno(input_context_));
-    return false;
-  }
-
-  // Wait until |input_context_| is ready.  pa_threaded_mainloop_wait() must be
-  // called after pa_context_get_state() in case the context is already ready,
-  // otherwise pa_threaded_mainloop_wait() will hang indefinitely.
-  while (true) {
-    pa_context_state_t context_state = pa_context_get_state(input_context_);
-    if (!PA_CONTEXT_IS_GOOD(context_state))
-      return false;
-    if (context_state == PA_CONTEXT_READY)
-      break;
-    pa_threaded_mainloop_wait(input_mainloop_);
-  }
-
-  return true;
-}
-
 void AudioManagerPulse::DestroyPulse() {
   if (!input_mainloop_) {
     DCHECK(!input_context_);
     return;
   }
 
   {
     AutoPulseLock auto_lock(input_mainloop_);
     if (input_context_) {
       // Clear our state callback.
@@ skipping 45 matching lines @@
 void AudioManagerPulse::SampleRateInfoCallback(pa_context* context,
                                                const pa_server_info* info,
                                                void* user_data) {
   AudioManagerPulse* manager = reinterpret_cast<AudioManagerPulse*>(user_data);
 
   manager->native_input_sample_rate_ = info->sample_spec.rate;
   pa_threaded_mainloop_signal(manager->input_mainloop_, 0);
 }
 
 }  // namespace media