CmaMediaPipelineClient to watch media pipeline status

chromecast/media/cma/pipeline/media_pipeline_impl.cc

 // Copyright 2014 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 "chromecast/media/cma/pipeline/media_pipeline_impl.h"
 
 #include "base/bind.h"
 #include "base/callback.h"
 #include "base/callback_helpers.h"
 #include "base/location.h"
@@ skipping 48 matching lines @@
       statistics_rolling_counter_(0),
       weak_factory_(this) {
   CMALOG(kLogControl) << __FUNCTION__;
   weak_this_ = weak_factory_.GetWeakPtr();
   thread_checker_.DetachFromThread();
 }
 
 MediaPipelineImpl::~MediaPipelineImpl() {
   CMALOG(kLogControl) << __FUNCTION__;
   DCHECK(thread_checker_.CalledOnValidThread());
+
+  weak_factory_.InvalidateWeakPtrs();
+
+  // Since av pipeline still need to access device components in their
+  // destructor, it's important to delete them first.
+  video_pipeline_.reset();
+  audio_pipeline_.reset();
+  media_pipeline_backend_.reset();
+  client_.device_components_destroy_cb.Run();

[halliwell, 2015/08/25 00:48:34]

I think you have to check is_null before calling?

[yucliu1, 2015/08/25 00:53:11]

The SetClient requires that all the callbacks can not be null. And there's no
other places reset the callbacks.

[halliwell, 2015/08/25 01:02:49]

You didn't add DCHECKs to SetClient for these new CBs.  And you will find a
variety of other users of media pipeline (e.g. unit tests) need updating to set
the new CBs in their clients.  Given that these other users don't actually need
the CB, you may want to consider allowing it to be null.

[yucliu1, 2015/08/25 04:27:58]

Done.

 }
 
 void MediaPipelineImpl::Initialize(
     LoadType load_type,
     scoped_ptr<MediaPipelineBackend> media_pipeline_backend) {
   CMALOG(kLogControl) << __FUNCTION__;
   DCHECK(thread_checker_.CalledOnValidThread());
   media_pipeline_backend_.reset(media_pipeline_backend.release());
   clock_device_ = media_pipeline_backend_->GetClock();
+  client_.device_components_create_cb.Run();

[halliwell, 2015/08/25 00:48:34]

same here.

[yucliu1, 2015/08/25 04:27:58]

Done.

 
   if (load_type == kLoadTypeURL || load_type == kLoadTypeMediaSource) {
     base::TimeDelta low_threshold(kLowBufferThresholdURL);
     base::TimeDelta high_threshold(kHighBufferThresholdURL);
     if (load_type == kLoadTypeMediaSource) {
       low_threshold = kLowBufferThresholdMediaSource;
       high_threshold = kHighBufferThresholdMediaSource;
     }
     scoped_refptr<BufferingConfig> buffering_config(
         new BufferingConfig(low_threshold, high_threshold));
@@ skipping 280 matching lines @@
 
 void MediaPipelineImpl::OnError(::media::PipelineStatus error) {
   DCHECK(thread_checker_.CalledOnValidThread());
   DCHECK_NE(error, ::media::PIPELINE_OK) << "PIPELINE_OK is not an error!";
   if (!client_.error_cb.is_null())
     client_.error_cb.Run(error);
 }
 
 }  // namespace media
 }  // namespace chromecast