Share one thread between all AudioOutputControllers instead of creating one per stream.

media/audio/win/audio_manager_win.cc

 // Copyright (c) 2006-2010 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/audio_io.h"
 
 #include <windows.h>
 #include <mmsystem.h>
 
-#include "base/at_exit.h"
 #include "base/basictypes.h"
 #include "media/audio/fake_audio_input_stream.h"
 #include "media/audio/fake_audio_output_stream.h"
 #include "media/audio/win/audio_manager_win.h"
 #include "media/audio/win/wavein_input_win.h"
 #include "media/audio/win/waveout_output_win.h"
 
 namespace {
 
 // The next 3 constants are some sensible limits to prevent integer overflow
@@ skipping 14 matching lines @@
 
 const int kMaxInputChannels = 2;
 const int kMaxSamplesPerPacket = kMaxSampleRate;
 // We use 3 buffers for recording audio so that if a recording callback takes
 // some time to return we won't lose audio. More buffers while recording are
 // ok because they don't introduce any delay in recording, unlike in playback
 // where you first need to fill in that number of buffers before starting to
 // play.
 const int kNumInputBuffers = 3;
 
-AudioManagerWin* g_audio_manager = NULL;
-
 }  // namespace.
 
 bool AudioManagerWin::HasAudioOutputDevices() {
   return (::waveOutGetNumDevs() != 0);
 }
 
 bool AudioManagerWin::HasAudioInputDevices() {
   return (::waveInGetNumDevs() != 0);
 }
 
@@ skipping 61 matching lines @@
 
 void AudioManagerWin::MuteAll() {
 }
 
 void AudioManagerWin::UnMuteAll() {
 }
 
 AudioManagerWin::~AudioManagerWin() {
 }
 
-void DestroyAudioManagerWin(void* param) {
-  delete g_audio_manager;
-  g_audio_manager = NULL;
+// static
+AudioManager* AudioManager::CreateAudioManager() {
+  return new AudioManagerWin();
 }
-
-AudioManager* AudioManager::GetAudioManager() {
-  if (!g_audio_manager) {
-    g_audio_manager = new AudioManagerWin();
-    base::AtExitManager::RegisterCallback(&DestroyAudioManagerWin, NULL);
-  }
-  return g_audio_manager;
-}