Mojo interfaces needed for switching audio rendering stream creation and closing from IPC to Mojo

content/browser/media/audio_output_impl.cc

+// Copyright 2015 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 "content/browser/media/audio_output_impl.h"
+
+#include <utility>
+
+#include "base/bind.h"
+#include "base/bind_helpers.h"
+#include "base/files/file.h"
+#include "base/logging.h"
+#include "base/memory/weak_ptr.h"
+#include "base/strings/string_number_conversions.h"
+#include "content/browser/media/webrtc/webrtc_internals.h"
+#include "content/public/browser/browser_thread.h"
+#include "content/public/browser/browser_thread.h"
+#include "content/public/browser/render_process_host.h"
+#include "content/public/common/child_process_host.h"
+#include "mojo/public/cpp/system/handle.h"
+
+namespace {
+
+media::AudioParameters convert(
+    const content::mojom::AudioOutputStreamParametersPtr& input) {
+  media::AudioParameters output(
+      static_cast<media::AudioParameters::Format>(input->format_),
+      static_cast<media::ChannelLayout>(input->channel_layout_),
+      input->sample_rate_, input->bits_per_sample_, input->frames_per_buffer_);
+  output.set_channels(input->channels_);
+  output.set_effects(input->effects_);
+  return output;
+}
+
+}  // namespace
+
+namespace content {
+
+AudioOutputStreamImpl::AudioOutputStreamImpl(
+    mojo::InterfaceRequest<AudioOutputStream> request,
+    int stream_id,
+    AudioRendererHost::AudioEntry* entry,
+    AudioRendererHost* audio_renderer_host)
+    : binding_(this, std::move(request)),
+      stream_id_(stream_id),
+      entry_(entry),

[Henrik Grunell, 2016/04/19 15:36:08]

Seems like the entry isn't used? Also, the renderer host already keeps track of
the entries by stream id so it should only be necessary to know about the
renderer host in this class.

[rchtara, 2016/04/21 09:10:17]

Done.

+      audio_renderer_host_(audio_renderer_host) {
+}
+
+void AudioOutputStreamImpl::Close() {
+  audio_renderer_host_->OnCloseStream(stream_id_);
+}
+
+AudioOutputStreamImpl::~AudioOutputStreamImpl() {
+}
+
+AudioOutputImpl::AudioOutputImpl(mojom::AudioOutputRequest request)
+    : binding_(this) {
+  BrowserThread::PostTask(
+      BrowserThread::IO, FROM_HERE,
+      base::Bind(&AudioOutputImpl::InitMojo, base::Unretained(this),

[Henrik Grunell, 2016/04/19 15:36:08]

How is base::Unretained safe here?

[rchtara, 2016/04/21 10:15:23]

Done.

+                 base::Passed(&request)));
+}
+
+AudioOutputImpl::~AudioOutputImpl() {
+}
+
+void AudioOutputImpl::CreateStream(int stream_id,
+                                   int render_frame_id,
+                                   mojom::AudioOutputStreamParametersPtr params,
+                                   const CreateStreamCallback& callback) {
+  mojom::AudioOutputStreamPtr stream;
+  media::AudioParameters audio_params = convert(params);
+
+  audio_renderer_host_->OnCreateStream(stream_id, render_frame_id, audio_params,

[Henrik Grunell, 2016/04/19 15:36:08]

I think you should remove "On" from OnCreateStream - it's an IPC style. (Unless
that's also a common mojo style.)

[rchtara, 2016/04/21 09:10:17]

Done.

+                                       callback);
+}
+
+mojom::AudioOutputStreamPtr* AudioOutputImpl::StreamFactory(
+    int stream_id,
+    AudioRendererHost::AudioEntry* entry,
+    AudioRendererHost* audio_renderer_host) {
+  mojom::AudioOutputStreamPtr* stream = new mojom::AudioOutputStreamPtr();
+  AudioOutputStreamImpl* stream_ptr(new AudioOutputStreamImpl(
+      mojo::GetProxy(stream), stream_id, entry, audio_renderer_host));
+  entry->set_stream_ptr(stream_ptr);
+  stream_impls[stream_id] = make_scoped_ptr(stream_ptr);
+  return stream;
+}
+
+void AudioOutputImpl::InitMojo(mojo::InterfaceRequest<AudioOutput> request) {
+  binding_.Bind(std::move(request));
+  binding_.set_connection_error_handler(base::Bind(
+      base::Bind(&AudioOutputImpl::OnDisconnect, base::Unretained(this)),
+      base::Unretained(this)));
+}
+
+void AudioOutputImpl::OnDisconnect(AudioOutputImpl* impl) {
+  DLOG(ERROR) << "Mojo client connection error";
+}
+
+}  // namespace content