Implement AudioOutputProxy.

media/audio/audio_output_proxy.cc

+// Copyright (c) 2010 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/audio/audio_output_proxy.h"
+
+#include "base/logging.h"
+#include "base/message_loop.h"
+#include "base/task.h"
+#include "media/audio/audio_manager.h"
+#include "media/audio/audio_output_dispatcher.h"
+
+AudioOutputProxy::AudioOutputProxy(AudioOutputDispatcher* dispatcher)
+    : dispatcher_(dispatcher),
+      state_(kCreated),
+      physical_stream_(NULL),
+      volume_(1.0) {
+  DCHECK_EQ(MessageLoop::current(), dispatcher_->message_loop());
+}
+
+AudioOutputProxy::~AudioOutputProxy() {
+  DCHECK_EQ(MessageLoop::current(), dispatcher_->message_loop());
+  DCHECK(state_ == kCreated || state_ == kClosed);
+  DCHECK(!physical_stream_);
+}
+
+bool AudioOutputProxy::Open() {
+  DCHECK_EQ(MessageLoop::current(), dispatcher_->message_loop());
+  DCHECK_EQ(state_, kCreated);
+
+  if (!dispatcher_->StreamOpened()) {
+    state_ = kError;
+    return false;
+  }
+
+  state_ = kOpened;
+  return true;
+}
+
+void AudioOutputProxy::Start(AudioSourceCallback* callback) {
+  DCHECK_EQ(MessageLoop::current(), dispatcher_->message_loop());
+  DCHECK(physical_stream_ == NULL);
+  DCHECK_EQ(state_, kOpened);
+
+  physical_stream_= dispatcher_->StreamStarted();
+  if (!physical_stream_) {
+    state_ = kError;
+    callback->OnError(this, 0);
+    return;
+  }
+
+  physical_stream_->SetVolume(volume_);
+  physical_stream_->Start(callback);
+  state_ = kPlaying;
+}
+
+void AudioOutputProxy::Stop() {
+  DCHECK_EQ(MessageLoop::current(), dispatcher_->message_loop());
+  if (state_ != kPlaying)
+    return;
+
+  DCHECK(physical_stream_);
+  physical_stream_->Stop();
+  dispatcher_->StreamStopped(physical_stream_);
+  physical_stream_ = NULL;
+  state_ = kOpened;
+}
+
+void AudioOutputProxy::SetVolume(double volume) {
+  DCHECK_EQ(MessageLoop::current(), dispatcher_->message_loop());
+  volume_ = volume;
+  if (physical_stream_) {
+    physical_stream_->SetVolume(volume);
+  }
+}
+
+void AudioOutputProxy::GetVolume(double* volume) {
+  DCHECK_EQ(MessageLoop::current(), dispatcher_->message_loop());
+  *volume = volume_;
+}
+
+void AudioOutputProxy::Close() {
+  DCHECK_EQ(MessageLoop::current(), dispatcher_->message_loop());
+  DCHECK(state_ == kCreated || state_ == kError || state_ == kOpened);
+  DCHECK(!physical_stream_);
+
+  if (state_ != kCreated) {
+    dispatcher_->StreamClosed();
+  }
+  dispatcher_->message_loop()->DeleteSoon(FROM_HERE, this);
+  state_ = kClosed;
+}