Remove the IPC to request DemuxerConfigs when config changes

media/base/android/media_decoder_job.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/base/android/media_decoder_job.h"
 
 #include "base/bind.h"
 #include "base/callback_helpers.h"
 #include "base/debug/trace_event.h"
 #include "base/message_loop/message_loop_proxy.h"
@@ skipping 84 matching lines @@
   if (HasData()) {
     DVLOG(1) << __FUNCTION__ << " : using previously received data";
     ui_task_runner_->PostTask(FROM_HERE, prefetch_cb);
     return;
   }
 
   DVLOG(1) << __FUNCTION__ << " : requesting data";
   RequestData(prefetch_cb);
 }
 
-bool MediaDecoderJob::Decode(
+DemuxerConfigs* MediaDecoderJob::Decode(
     base::TimeTicks start_time_ticks,
     base::TimeDelta start_presentation_timestamp,
     const DecoderCallback& callback) {
   DCHECK(decode_cb_.is_null());
   DCHECK(on_data_received_cb_.is_null());
   DCHECK(ui_task_runner_->BelongsToCurrentThread());
 
   decode_cb_ = callback;
 
   if (!HasData()) {
     RequestData(base::Bind(&MediaDecoderJob::DecodeCurrentAccessUnit,
                            base::Unretained(this),
                            start_time_ticks,
                            start_presentation_timestamp));
-    return true;
+    return NULL;
   }
 
   if (DemuxerStream::kConfigChanged == CurrentAccessUnit().status) {
     // Clear received data because we need to handle a config change.
     decode_cb_.Reset();
-    ClearData();
-    return false;
+    size_t index = CurrentReceivedDataChunkIndex();
+    return &(received_data_[index].demuxer_configs[0]);

[wolenetz, 2014/05/05 22:06:55]

Before returning, please protect against [0] which could exceed the bounds of an
empty demuxer_configs vector; add something like:
CHECK_EQ(1, received_data_[index].demuxer_configs.size());

I'm also concerned about the unspoken lifetime of the returned pointer. ISTM
that returning a scoped_ptr to a copy of our MDJ-owned configs would be less
fragile and less tightly bound.

[qinmin, 2014/05/06 18:05:26]

Changed this function to return a new pointer and asked the caller to own it.

On 2014/05/05 22:06:55, wolenetz wrote:

   }
 
   DecodeCurrentAccessUnit(start_time_ticks, start_presentation_timestamp);
-  return true;
+  return NULL;
 }
 
 void MediaDecoderJob::StopDecode() {
   DCHECK(ui_task_runner_->BelongsToCurrentThread());
   DCHECK(is_decoding());
   stop_decode_pending_ = true;
 }
 
 void MediaDecoderJob::Flush() {
   DCHECK(decode_cb_.is_null());
@@ skipping 313 matching lines @@
   };
 
   stop_decode_pending_ = false;
   base::ResetAndReturn(&decode_cb_).Run(
       status, current_presentation_timestamp, max_presentation_timestamp);
 }
 
 const AccessUnit& MediaDecoderJob::CurrentAccessUnit() const {
   DCHECK(ui_task_runner_->BelongsToCurrentThread());
   DCHECK(HasData());
-  int index = NoAccessUnitsRemainingInChunk(true) ?
+  size_t index = CurrentReceivedDataChunkIndex();
+  return received_data_[index].access_units[access_unit_index_[index]];
+}
+
+size_t MediaDecoderJob::CurrentReceivedDataChunkIndex() const {
+  return NoAccessUnitsRemainingInChunk(true) ?
       inactive_demuxer_data_index() : current_demuxer_data_index_;
-  return received_data_[index].access_units[access_unit_index_[index]];
 }
 
 bool MediaDecoderJob::NoAccessUnitsRemainingInChunk(
     bool is_active_chunk) const {
   DCHECK(ui_task_runner_->BelongsToCurrentThread());
   size_t index = is_active_chunk ? current_demuxer_data_index_ :
       inactive_demuxer_data_index();
   return received_data_[index].access_units.size() <= access_unit_index_[index];
 }
 
@@ skipping 25 matching lines @@
 }
 
 void MediaDecoderJob::InitializeReceivedData() {
   for (size_t i = 0; i < 2; ++i) {
     received_data_[i] = DemuxerData();
     access_unit_index_[i] = 0;
   }
 }
 
 }  // namespace media