Add Stop() to AudioDecoder.

media/filters/audio_renderer_impl.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/filters/audio_renderer_impl.h"
 
 #include <math.h>
 
 #include <algorithm>
 
@@ skipping 144 matching lines @@
   ResetDecoder();
 }
 
 void AudioRendererImpl::ResetDecoder() {
   DCHECK(task_runner_->BelongsToCurrentThread());
   decoder_->Reset(BindToCurrentLoop(
       base::Bind(&AudioRendererImpl::ResetDecoderDone, weak_this_)));
 }
 
 void AudioRendererImpl::ResetDecoderDone() {
-  base::AutoLock auto_lock(lock_);
   if (state_ == kStopped)

[DaleCurtis, 2014/01/09 01:24:49]

State must be checked under lock; it can be changed on the audio thread. See the
comment on |lock_| for which variables must only be accessed under lock.

Just the callback should be run outside of lock.  Also it'd be helpful if this
method had a DCHECK(task_runnner_->BelongsToCurrentThread());  Ditto for
StopDecoderDone().

     return;
 
   DCHECK_EQ(state_, kPaused);
   DCHECK(!flush_cb_.is_null());
 
-  audio_time_buffered_ = kNoTimestamp();
-  current_time_ = kNoTimestamp();
-  received_end_of_stream_ = false;
-  rendered_end_of_stream_ = false;
-  preroll_aborted_ = false;
+  {
+    base::AutoLock auto_lock(lock_);
+    audio_time_buffered_ = kNoTimestamp();
+    current_time_ = kNoTimestamp();
+    received_end_of_stream_ = false;
+    rendered_end_of_stream_ = false;
+    preroll_aborted_ = false;
 
-  earliest_end_time_ = now_cb_.Run();
-  splicer_->Reset();
-  algorithm_->FlushBuffers();
+    earliest_end_time_ = now_cb_.Run();
+    splicer_->Reset();
+    algorithm_->FlushBuffers();
+  }
 
   base::ResetAndReturn(&flush_cb_).Run();
 }
 
+void AudioRendererImpl::StopDecoderDone() {
+  if (state_ == kStopped)
+    return;
+
+  DCHECK(!stop_cb_.is_null());
+  DCHECK(init_cb_.is_null());
+
+  {
+    base::AutoLock auto_lock(lock_);
+    ChangeState_Locked(kStopped);
+    algorithm_.reset();
+    init_cb_.Reset();
+    underflow_cb_.Reset();
+    time_cb_.Reset();
+    flush_cb_.Reset();
+  }
+
+  base::ResetAndReturn(&stop_cb_).Run();
+}
+
 void AudioRendererImpl::Stop(const base::Closure& callback) {
   DCHECK(task_runner_->BelongsToCurrentThread());
   DCHECK(!callback.is_null());
 
   // TODO(scherkus): Consider invalidating |weak_factory_| and replacing
   // task-running guards that check |state_| with DCHECK().
 
   if (sink_) {
     sink_->Stop();
     sink_ = NULL;
   }
 
-  {
-    base::AutoLock auto_lock(lock_);
-    ChangeState_Locked(kStopped);
-    algorithm_.reset(NULL);
-    init_cb_.Reset();
-    underflow_cb_.Reset();
-    time_cb_.Reset();
-    flush_cb_.Reset();
+  stop_cb_ = callback;
+
+  if (decoder_) {
+    DCHECK(task_runner_->BelongsToCurrentThread());
+    decoder_->Stop(BindToCurrentLoop(
+        base::Bind(&AudioRendererImpl::StopDecoderDone, weak_this_)));
+    return;
   }
 
-  callback.Run();
+  StopDecoderDone();
 }
 
 void AudioRendererImpl::Preroll(base::TimeDelta time,
                                 const PipelineStatusCB& cb) {
   DCHECK(task_runner_->BelongsToCurrentThread());
 
   base::AutoLock auto_lock(lock_);
   DCHECK(!sink_playing_);
   DCHECK_EQ(state_, kPaused);
   DCHECK(!pending_read_) << "Pending read must complete before seeking";
@@ skipping 482 matching lines @@
   }
 }
 
 void AudioRendererImpl::ChangeState_Locked(State new_state) {
   DVLOG(1) << __FUNCTION__ << " : " << state_ << " -> " << new_state;
   lock_.AssertAcquired();
   state_ = new_state;
 }
 
 }  // namespace media