Reland 153623004: Remove the unified IO code on the browser

content/browser/renderer_host/media/audio_sync_reader.h

 // Copyright (c) 2012 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.
 
 #ifndef CONTENT_BROWSER_RENDERER_HOST_MEDIA_AUDIO_SYNC_READER_H_
 #define CONTENT_BROWSER_RENDERER_HOST_MEDIA_AUDIO_SYNC_READER_H_
 
 #include "base/file_descriptor_posix.h"
 #include "base/process/process.h"
 #include "base/sync_socket.h"
 #include "base/synchronization/lock.h"
 #include "base/time/time.h"
 #include "media/audio/audio_output_controller.h"
 #include "media/base/audio_bus.h"
 
 namespace base {
 class SharedMemory;
 }
 
 namespace content {
 
 // A AudioOutputController::SyncReader implementation using SyncSocket. This
 // is used by AudioOutputController to provide a low latency data source for
 // transmitting audio packets between the browser process and the renderer
 // process.
 class AudioSyncReader : public media::AudioOutputController::SyncReader {
  public:
   AudioSyncReader(base::SharedMemory* shared_memory,
-                  const media::AudioParameters& params,
-                  int input_channels);
+                  const media::AudioParameters& params);
 
   virtual ~AudioSyncReader();
 
   // media::AudioOutputController::SyncReader implementations.
   virtual void UpdatePendingBytes(uint32 bytes) OVERRIDE;
   virtual void Read(const media::AudioBus* source,
                     media::AudioBus* dest) OVERRIDE;
   virtual void Close() OVERRIDE;
 
   bool Init();
   bool PrepareForeignSocketHandle(base::ProcessHandle process_handle,
 #if defined(OS_WIN)
                                   base::SyncSocket::Handle* foreign_handle);
 #else
                                   base::FileDescriptor* foreign_handle);
 #endif
 
  private:
   // Blocks until data is ready for reading or a timeout expires.  Returns false
   // if an error or timeout occurs.
   bool WaitUntilDataIsReady();
 
   const base::SharedMemory* const shared_memory_;
 
-  // Number of input channels for synchronized I/O.
-  const int input_channels_;
-
   // Mutes all incoming samples. This is used to prevent audible sound
   // during automated testing.
   const bool mute_audio_;
 
   // Socket for transmitting audio data.
   scoped_ptr<base::CancelableSyncSocket> socket_;
 
   // Socket to be used by the renderer. The reference is released after
   // PrepareForeignSocketHandle() is called and ran successfully.
   scoped_ptr<base::CancelableSyncSocket> foreign_socket_;
 
   // Shared memory wrapper used for transferring audio data to Read() callers.
   scoped_ptr<media::AudioBus> output_bus_;
 
-  // Shared memory wrapper used for transferring audio data from Read() callers.
-  scoped_ptr<media::AudioBus> input_bus_;
-
   // Maximum amount of audio data which can be transferred in one Read() call.
   const int packet_size_;
 
   // Track the number of times the renderer missed its real-time deadline and
   // report a UMA stat during destruction.
   size_t renderer_callback_count_;
   size_t renderer_missed_callback_count_;
 
   // The maximum amount of time to wait for data from the renderer.  Calculated
   // from the parameters given at construction.
   const base::TimeDelta maximum_wait_time_;
 
   // The index of the audio buffer we're expecting to be sent from the renderer;
   // used to block with timeout for audio data.
   uint32 buffer_index_;
 
   DISALLOW_COPY_AND_ASSIGN(AudioSyncReader);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_MEDIA_AUDIO_SYNC_READER_H_