Finish plumbing MojoVideoDecoder.

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 91d0b9bf8b479dff3c424076f24f208fd43ff4a1..f2724aab9680e0feb9d4eacd3f4fd5137b043dec 100644
--- a/media/mojo/services/mojo_audio_decoder_service.cc
+++ b/media/mojo/services/mojo_audio_decoder_service.cc
@@ -14,20 +14,6 @@
 
 namespace media {
 
-static mojom::AudioDecoder::DecodeStatus ConvertDecodeStatus(
-    media::DecodeStatus status) {
-  switch (status) {
-    case media::DecodeStatus::OK:
-      return mojom::AudioDecoder::DecodeStatus::OK;
-    case media::DecodeStatus::ABORTED:
-      return mojom::AudioDecoder::DecodeStatus::ABORTED;
-    case media::DecodeStatus::DECODE_ERROR:
-      return mojom::AudioDecoder::DecodeStatus::DECODE_ERROR;
-  }
-  NOTREACHED();
-  return mojom::AudioDecoder::DecodeStatus::DECODE_ERROR;
-}
-
 MojoAudioDecoderService::MojoAudioDecoderService(
     base::WeakPtr<MojoCdmServiceContext> mojo_cdm_service_context,
     std::unique_ptr<media::AudioDecoder> decoder,
@@ -95,7 +81,7 @@ void MojoAudioDecoderService::Decode(mojom::DecoderBufferPtr buffer,
   scoped_refptr<DecoderBuffer> media_buffer =
       ReadDecoderBuffer(std::move(buffer));
   if (!media_buffer) {
-    callback.Run(ConvertDecodeStatus(media::DecodeStatus::DECODE_ERROR));
+    callback.Run(mojom::DecodeStatus::DECODE_ERROR);
     return;
   }
 
@@ -127,7 +113,7 @@ void MojoAudioDecoderService::OnInitialized(const InitializeCallback& callback,
 void MojoAudioDecoderService::OnDecodeStatus(const DecodeCallback& callback,
                                              media::DecodeStatus status) {
   DVLOG(3) << __FUNCTION__ << " status:" << status;
-  callback.Run(ConvertDecodeStatus(status));
+  callback.Run(static_cast<mojom::DecodeStatus>(status));
 }
 
 void MojoAudioDecoderService::OnResetDone(const ResetCallback& callback) {
@@ -152,28 +138,29 @@ scoped_refptr<DecoderBuffer> MojoAudioDecoderService::ReadDecoderBuffer(
     return media_buffer;
 
   // Wait for the data to become available in the DataPipe.
+  MojoResult result;
   MojoHandleSignalsState state;
-  CHECK_EQ(MOJO_RESULT_OK,
-           MojoWait(consumer_handle_.get().value(), MOJO_HANDLE_SIGNAL_READABLE,
-                    MOJO_DEADLINE_INDEFINITE, &state));
-
+  result = MojoWait(consumer_handle_.get().value(), MOJO_HANDLE_SIGNAL_READABLE,
+                    MOJO_DEADLINE_INDEFINITE, &state);
+  if (result != MOJO_RESULT_OK ||
+      !(state.satisfied_signals & MOJO_HANDLE_SIGNAL_READABLE)) {
+    return nullptr;
+  }
   if (state.satisfied_signals & MOJO_HANDLE_SIGNAL_PEER_CLOSED) {
     DVLOG(1) << __FUNCTION__ << ": Peer closed the data pipe";
-    return scoped_refptr<DecoderBuffer>();
+    return nullptr;
   }
 
-  CHECK_EQ(MOJO_HANDLE_SIGNAL_READABLE,
-           state.satisfied_signals & MOJO_HANDLE_SIGNAL_READABLE);
-
   // Read the inner data for the DecoderBuffer from our DataPipe.
-  uint32_t bytes_to_read =
-      base::checked_cast<uint32_t>(media_buffer->data_size());
-  DCHECK_GT(bytes_to_read, 0u);
-  uint32_t bytes_read = bytes_to_read;
-  CHECK_EQ(ReadDataRaw(consumer_handle_.get(), media_buffer->writable_data(),
-                       &bytes_read, MOJO_READ_DATA_FLAG_ALL_OR_NONE),
-           MOJO_RESULT_OK);
-  CHECK_EQ(bytes_to_read, bytes_read);
+  uint32_t data_size = buffer->data_size;
+  if (data_size != media_buffer->data_size())

[Tima Vaisburd, 2016/05/18 00:32:16]

Drive-by: how can they be different?

[sandersd (OOO until July 31), 2016/05/18 00:49:29]

They can't (assuming size_t is of higher integer rank than uint32_t), but I
didn't want to have to trust that path when reasoning about this code.

[sandersd (OOO until July 31), 2016/05/18 00:50:42]

*same or higher

[dcheng, 2016/05/20 21:18:22]

I'd suggest DCHECK() or static_assert in the TypeConverter, this makes it look
like a legitimate runtime condition that needs to be handled.

[sandersd (OOO until July 31), 2016/05/20 22:27:14]

Converted to a CHECK() (in MojoVideoDecoderService; MojoAudioDecoderService was
updated in https://codereview.chromium.org/1982883003/)

+    return nullptr;
+
+  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)
+    return nullptr;
 
   return media_buffer;
 }