media: Add MojoDecoderBuffer{Reader|Writer}

media/mojo/services/mojo_audio_decoder_service.cc

Index: media/mojo/services/mojo_audio_decoder_service.cc
diff --git a/media/mojo/services/mojo_audio_decoder_service.cc b/media/mojo/services/mojo_audio_decoder_service.cc
index 3de0b40b6e1cf02bcaaf5af1b61a61aa04c67463..9b7a6f1bac008e4af8f16cb6832e28f5755b6dc9 100644
--- a/media/mojo/services/mojo_audio_decoder_service.cc
+++ b/media/mojo/services/mojo_audio_decoder_service.cc
@@ -10,6 +10,7 @@
 #include "media/base/cdm_context.h"
 #include "media/base/media_keys.h"
 #include "media/mojo/common/media_type_converters.h"
+#include "media/mojo/common/mojo_decoder_buffer_converter.h"
 #include "media/mojo/services/mojo_cdm_service_context.h"
 
 namespace media {
@@ -71,7 +72,9 @@ void MojoAudioDecoderService::Initialize(mojom::AudioDecoderClientPtr client,
 void MojoAudioDecoderService::SetDataSource(
     mojo::ScopedDataPipeConsumerHandle receive_pipe) {
   DVLOG(1) << __FUNCTION__;
-  consumer_handle_ = std::move(receive_pipe);
+
+  mojo_decoder_buffer_reader_.reset(
+      new MojoDecoderBufferReader(std::move(receive_pipe)));
 }
 
 void MojoAudioDecoderService::Decode(mojom::DecoderBufferPtr buffer,
@@ -79,7 +82,7 @@ void MojoAudioDecoderService::Decode(mojom::DecoderBufferPtr buffer,
   DVLOG(3) << __FUNCTION__;
 
   scoped_refptr<DecoderBuffer> media_buffer =
-      ReadDecoderBuffer(std::move(buffer));
+      mojo_decoder_buffer_reader_->ReadDecoderBuffer(buffer);
   if (!media_buffer) {
     callback.Run(mojom::DecodeStatus::DECODE_ERROR);
     return;
@@ -129,39 +132,4 @@ void MojoAudioDecoderService::OnAudioBufferReady(
   client_->OnBufferDecoded(mojom::AudioBuffer::From(audio_buffer));
 }
 
-scoped_refptr<DecoderBuffer> MojoAudioDecoderService::ReadDecoderBuffer(
-    mojom::DecoderBufferPtr buffer) {
-  scoped_refptr<DecoderBuffer> media_buffer(
-      buffer.To<scoped_refptr<DecoderBuffer>>());
-
-  if (media_buffer->end_of_stream())
-    return media_buffer;
-
-  // Wait for the data to become available in the DataPipe.
-  MojoHandleSignalsState state;
-  MojoResult result =
-      MojoWait(consumer_handle_.get().value(), MOJO_HANDLE_SIGNAL_READABLE,
-               MOJO_DEADLINE_INDEFINITE, &state);
-
-  if (result != MOJO_RESULT_OK) {
-    DVLOG(1) << __FUNCTION__ << ": Peer closed the data pipe";
-    return nullptr;
-  }
-
-  // Read the inner data for the DecoderBuffer from our DataPipe.
-  uint32_t data_size = static_cast<uint32_t>(media_buffer->data_size());
-  DCHECK_EQ(data_size, buffer->data_size);
-  DCHECK_GT(data_size, 0u);
-
-  uint32_t bytes_read = data_size;
-  result = ReadDataRaw(consumer_handle_.get(), media_buffer->writable_data(),
-                       &bytes_read, MOJO_READ_DATA_FLAG_ALL_OR_NONE);
-  if (result != MOJO_RESULT_OK || bytes_read != data_size) {
-    DVLOG(1) << __FUNCTION__ << ": reading from pipe failed";
-    return nullptr;
-  }
-
-  return media_buffer;
-}
-
 }  // namespace media