// 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 MEDIA_AUDIO_AUDIO_INPUT_IPC_H_
#define MEDIA_AUDIO_AUDIO_INPUT_IPC_H_
#include "base/memory/shared_memory.h"
#include "base/sync_socket.h"
#include "media/audio/audio_parameters.h"
#include "media/base/media_export.h"
namespace media {
// Contains IPC notifications for the state of the server side
// (AudioInputController) audio state changes and when an AudioInputController
// has been created. Implemented by AudioInputDevice.
class MEDIA_EXPORT AudioInputIPCDelegate {
public:
// Valid states for the input stream.
enum State {
kRecording,
kStopped,
kError
};
// Called when an AudioInputController has been created.
// The shared memory |handle| points to a memory section that's used to
// transfer data between the AudioInputDevice and AudioInputController
// objects. The implementation of OnStreamCreated takes ownership.
// The |socket_handle| is used by the AudioInputController to signal
// notifications that more data is available and can optionally provide
// parameter changes back. The AudioInputDevice must read from this socket
// and process the shared memory whenever data is read from the socket.
virtual void OnStreamCreated(base::SharedMemoryHandle handle,
base::SyncSocket::Handle socket_handle,
int length,
int total_segments) = 0;
// Called when state of an audio stream has changed.
virtual void OnStateChanged(State state) = 0;
// Called when the input stream volume has changed.
virtual void OnVolume(double volume) = 0;
// Called when the AudioInputIPC object is going away and/or when the
// IPC channel has been closed and no more IPC requests can be made.
// Implementations should delete their owned AudioInputIPC instance
// immediately.
virtual void OnIPCClosed() = 0;
protected:
virtual ~AudioInputIPCDelegate();
};
// Provides IPC functionality for an AudioInputIPCDelegate (e.g., an
// AudioInputDevice). The implementation should asynchronously deliver the
// messages to an AudioInputController object (or create one in the case of
// CreateStream()), that may live in a separate process.
class MEDIA_EXPORT AudioInputIPC {
public:
virtual ~AudioInputIPC();
// Sends a request to create an AudioInputController object in the peer
// process, and configures it to use the specified audio |params|. The
// |total_segments| indidates number of equal-lengthed segments in the shared
// memory buffer. Once the stream has been created, the implementation will
// notify |delegate| by calling OnStreamCreated().
virtual void CreateStream(AudioInputIPCDelegate* delegate,
int session_id,
const AudioParameters& params,
bool automatic_gain_control,
uint32 total_segments) = 0;
// Corresponds to a call to AudioInputController::Record() on the server side.
virtual void RecordStream() = 0;
// Sets the volume of the audio stream.
virtual void SetVolume(double volume) = 0;
// Closes the audio stream, which should shut down the corresponding
// AudioInputController in the peer process.
virtual void CloseStream() = 0;
};
} // namespace media
#endif // MEDIA_AUDIO_AUDIO_INPUT_IPC_H_