media: scaffolding and plumbing for MojoRenderer{Impl, Service}

media/mojo/services/mojo_renderer_service.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 "media/mojo/services/mojo_renderer_service.h"
+
+#include "base/bind.h"
+#include "base/memory/scoped_vector.h"
+#include "media/base/audio_decoder.h"
+#include "media/base/audio_renderer.h"
+#include "media/base/audio_renderer_sink.h"
+#include "media/base/decryptor.h"
+#include "media/filters/audio_renderer_impl.h"
+#include "media/mojo/services/mojo_demuxer_stream_adapter.h"
+#include "mojo/public/c/system/main.h"
+#include "mojo/public/cpp/application/application_connection.h"
+#include "mojo/public/cpp/application/application_delegate.h"
+#include "mojo/public/cpp/application/application_runner_chromium.h"
+#include "mojo/public/cpp/application/interface_factory_impl.h"
+
+namespace {
+
+// TODO(tim): We should use |connection|  passed to the MojoRendererService

[scherkus (not reviewing), 2014/09/09 20:35:33]

remove extra space before passed

[tim (not reviewing), 2014/09/10 23:08:31]

Done.

+// to connect to a MojoAudioRendererSink implementation that we would wrap in
+// media::AudioRendererSink and pass that to the AudioRendererImpl below.
+class DummyAudioRendererSink : public media::AudioRendererSink {

[scherkus (not reviewing), 2014/09/09 20:35:33]

you might be able to use media::NullAudioSink here instead

[tim (not reviewing), 2014/09/10 23:08:30]

Ah thanks!

+ virtual void Initialize(const media::AudioParameters& params,
+                          RenderCallback* callback) OVERRIDE {}
+  virtual void Start() OVERRIDE {}
+  virtual void Stop() OVERRIDE {}
+  virtual void Pause() OVERRIDE {}
+  virtual void Play() OVERRIDE {}
+  virtual bool SetVolume(double volume) OVERRIDE {
+    return true;
+  }
+ protected:
+  virtual ~DummyAudioRendererSink() {}
+};
+
+}  // namespace
+
+namespace media {
+
+class MojoRendererApplication
+    : public mojo::ApplicationDelegate,
+      public mojo::InterfaceFactory<mojo::MediaRenderer> {
+ public:
+  // mojo::ApplicationDelegate implementation.
+  virtual bool ConfigureIncomingConnection(
+      mojo::ApplicationConnection* connection) OVERRIDE {
+    connection->AddService(this);
+    return true;
+  }
+
+  // mojo::InterfaceFactory<mojo::MediaRenderer> implementation.
+  virtual void Create(
+      mojo::ApplicationConnection* connection,
+      mojo::InterfaceRequest<mojo::MediaRenderer> request) OVERRIDE {
+    mojo::BindToRequest(new MojoRendererService(connection), &request);
+  }
+};
+
+MojoRendererService::MojoRendererService(
+    mojo::ApplicationConnection* connection)
+    : hardware_config_(media::AudioParameters(), media::AudioParameters()),

[scherkus (not reviewing), 2014/09/09 20:35:33]

remove media:: here and everywhere else

[tim (not reviewing), 2014/09/10 23:08:30]

Done.

+      weak_factory_(this),
+      weak_this_(weak_factory_.GetWeakPtr()) {
+  audio_renderer_.reset(new media::AudioRendererImpl(
+      base::MessageLoop::current()->task_runner(),
+      new DummyAudioRendererSink(),
+      // TODO(tim): Figure out how to select decoders.
+      ScopedVector<media::AudioDecoder>(),
+      // TODO(tim): Not needed for now?
+      media::SetDecryptorReadyCB(),
+      hardware_config_));
+}
+
+MojoRendererService::~MojoRendererService() {}
+
+void MojoRendererService::Initialize(
+      mojo::DemuxerStreamPtr stream,
+      const mojo::Callback<void()>& callback) {
+  DCHECK(client());
+  stream_.reset(new MojoDemuxerStreamAdapter(stream.Pass(),
+      base::Bind(&MojoRendererService::OnStreamReady, weak_this_)));
+  init_cb_ = callback;;

[scherkus (not reviewing), 2014/09/09 20:35:33]

remove extra ;

[tim (not reviewing), 2014/09/10 23:08:30]

Done.

+}
+
+void MojoRendererService::Flush(const mojo::Callback<void()>& callback) {
+  NOTIMPLEMENTED();
+}
+
+void MojoRendererService::StartPlayingFrom(int64_t time_delta_usec) {
+  NOTIMPLEMENTED();
+}
+
+void MojoRendererService::SetPlaybackRate(float playback_rate) {
+  NOTIMPLEMENTED();
+}
+
+void MojoRendererService::SetVolume(float volume) {
+  NOTIMPLEMENTED();
+}
+
+void MojoRendererService::OnStreamReady() {
+  audio_renderer_->Initialize(
+      stream_.get(),
+      base::Bind(&MojoRendererService::OnAudioRendererInitializeDone,
+          weak_this_),
+      base::Bind(&MojoRendererService::OnUpdateStatistics, weak_this_),
+      base::Bind(&MojoRendererService::OnAudioTimeUpdate, weak_this_),
+      base::Bind(&MojoRendererService::OnBufferingStateChanged, weak_this_),
+      base::Bind(&MojoRendererService::OnAudioRendererEnded, weak_this_),
+      base::Bind(&MojoRendererService::OnError, weak_this_));
+}
+
+void MojoRendererService::OnAudioRendererInitializeDone(
+    media::PipelineStatus status) {
+  if (status != media::PIPELINE_OK) {
+    audio_renderer_.reset();
+    client()->OnError();
+  }
+  init_cb_.Run();
+}
+
+void MojoRendererService::OnUpdateStatistics(const PipelineStatistics& stats) {
+  NOTIMPLEMENTED();
+}
+
+void MojoRendererService::OnAudioTimeUpdate(base::TimeDelta time,
+                                            base::TimeDelta max_time) {
+  client()->OnTimeUpdate(time.InMilliseconds(), max_time.InMilliseconds());

[xhwang, 2014/09/10 00:00:52]

InMicroseconds?

[tim (not reviewing), 2014/09/10 23:08:30]

Uh oh.  Aaaaand here's why it's useful to have a time type :/

+}
+
+void MojoRendererService::OnBufferingStateChanged(
+    media::BufferingState new_buffering_state) {
+  client()->OnBufferingStateChange(
+      static_cast<mojo::BufferingState>(new_buffering_state));
+}
+
+void MojoRendererService::OnAudioRendererEnded() {
+  client()->OnEnded();
+}
+
+void MojoRendererService::OnError(PipelineStatus error) {
+  client()->OnError();

[xhwang, 2014/09/10 00:00:52]

Pass |error| in OnError()?

[tim (not reviewing), 2014/09/10 23:08:30]

In the last CL I thought you proposed that the renderer-side only needed to know
whether or not there was an error, so we didn't mojo-ify PipelineStatus and
plumb it through the MediaRendererClient mojom.

We can do that now if you like?

+}
+
+}  // namespace media
+
+MojoResult MojoMain(MojoHandle shell_handle) {

[scherkus (not reviewing), 2014/09/09 20:35:33]

does MojoMain() belong here?

[tim (not reviewing), 2014/09/10 23:08:30]

It typically goes wherever the ApplicationDelegate is.  We could add a separate
mojo_renderer_application_main.cc file that just declares an ApplicationDelegate
instance and defines the MojoMain, but pretty often for most of the (basic)
example apps that only vend one service you'll see it be a part of the service
implementation file instead of an extra .cc.  

It's up to you guys.

+  mojo::ApplicationRunnerChromium runner(new media::MojoRendererApplication);
+  return runner.Run(shell_handle);
+}