Add MessageLoop::AssertIdle(). Use in ChromeOS audio threads.

chrome/browser/chromeos/audio_mixer_alsa.cc

 // Copyright (c) 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 "chrome/browser/chromeos/audio_mixer_alsa.h"
 
 #include <alsa/asoundlib.h>
 
 #include "base/logging.h"
+#include "base/message_loop.h"
 #include "base/task.h"
 #include "base/threading/thread_restrictions.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/browser_thread.h"
 #include "chrome/browser/prefs/pref_service.h"
 #include "chrome/common/pref_names.h"
 
 namespace chromeos {
 
 // Connect to the ALSA mixer using their simple element API.  Init is performed
 // asynchronously on the worker thread.
 //
 // To get a wider range and finer control over volume levels, first the Master
 // level is set, then if the PCM element exists, the total level is refined by
 // adjusting that as well.  If the PCM element has more volume steps, it allows
 // for finer granularity in the total volume.
 
 typedef long alsa_long_t;  // 'long' is required for ALSA API calls.
 
 namespace {
 
-const char* kMasterVolume = "Master";
-const char* kPCMVolume = "PCM";
+const char kMasterVolume[] = "Master";
+const char kPCMVolume[] = "PCM";
 const double kDefaultMinVolume = -90.0;
 const double kDefaultMaxVolume = 0.0;
 const double kPrefVolumeInvalid = -999.0;
 const int kPrefMuteOff = 0;
 const int kPrefMuteOn = 1;
 const int kPrefMuteInvalid = 2;
 
 }  // namespace
 
 AudioMixerAlsa::AudioMixerAlsa()
     : min_volume_(kDefaultMinVolume),
       max_volume_(kDefaultMaxVolume),
       save_volume_(0),
       mixer_state_(UNINITIALIZED),
       alsa_mixer_(NULL),
       elem_master_(NULL),
       elem_pcm_(NULL) {
 }
 
 AudioMixerAlsa::~AudioMixerAlsa() {
   FreeAlsaMixer();
   if (thread_ != NULL) {
     // A ScopedAllowIO object is required to join the thread when calling Stop.
     // The worker thread should be idle at this time.
     // See http://crosbug.com/11110 for discussion.
     base::ThreadRestrictions::ScopedAllowIO allow_io_for_thread_join;
+    thread_->message_loop()->AssertIdle();
 
     thread_->Stop();
     thread_.reset();
   }
 }
 
 void AudioMixerAlsa::Init(InitDoneCallback* callback) {
   DCHECK(callback);
   if (!InitThread()) {
     callback->Run(false);
@@ skipping 368 matching lines @@
 
 void AudioMixerAlsa::SetElementMuted_Locked(snd_mixer_elem_t* elem, bool mute) {
   int enabled = mute ? 0 : 1;
   snd_mixer_selem_set_playback_switch_all(elem, enabled);
 
   VLOG(1) << "Set playback switch " << snd_mixer_selem_get_name(elem)
           << " to " << enabled;
 }
 
 }  // namespace chromeos
-