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// Copyright 2013 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_SNDIO_SNDIO_INPUT_H_
#define MEDIA_AUDIO_SNDIO_SNDIO_INPUT_H_
#include <stdint.h>
#include <string>
#include <sndio.h>
#include "base/compiler_specific.h"
#include "base/macros.h"
#include "base/memory/weak_ptr.h"
#include "base/time/time.h"
#include "media/audio/agc_audio_stream.h"
#include "media/audio/audio_io.h"
#include "media/audio/audio_device_description.h"
#include "media/base/audio_parameters.h"
namespace media {
class AudioManagerBase;
// call-backs invoked from C libraries, thus requiring C linkage
extern "C" {
// Invoked (on the real-time thread) at each sound card clock tick
void sndio_in_onmove(void *arg, int delta);
// Invoked (on the real-time thread) whenever the volume changes
void sndio_in_onvol(void *arg, unsigned int vol);
// Real-time thread entry point
void *sndio_in_threadstart(void *arg);
}
// Provides an input stream for audio capture based on the SNDIO PCM interface.
// This object is not thread safe and all methods should be invoked in the
// thread that created the object.
class SndioAudioInputStream : public AgcAudioStream<AudioInputStream> {
public:
// Pass this to the constructor if you want to attempt auto-selection
// of the audio recording device.
static const char kAutoSelectDevice[];
// Create a PCM Output stream for the SNDIO device identified by
// |device_name|. If unsure of what to use for |device_name|, use
// |kAutoSelectDevice|.
SndioAudioInputStream(AudioManagerBase* audio_manager,
const std::string& device_name,
const AudioParameters& params);
~SndioAudioInputStream() override;
// Implementation of AudioInputStream.
bool Open() override;
void Start(AudioInputCallback* callback) override;
void Stop() override;
void Close() override;
double GetMaxVolume() override;
void SetVolume(double volume) override;
double GetVolume() override;
bool IsMuted() override;
// C-linkage call-backs are friends to access private data
friend void sndio_in_onmove(void *arg, int delta);
friend void sndio_in_onvol(void *arg, unsigned int vol);
friend void *sndio_in_threadstart(void *arg);
private:
// Logs the error and invokes any registered callbacks.
void HandleError(const char* method, int error);
// Reads one or more buffers of audio from the device, passes on to the
// registered callback and schedules the next read.
void ReadAudio();
// Recovers from any device errors if possible.
bool Recover(int error);
// Non-refcounted pointer back to the audio manager.
// The AudioManager indirectly holds on to stream objects, so we don't
// want circular references. Additionally, stream objects live on the audio
// thread, which is owned by the audio manager and we don't want to addref
// the manager from that thread.
AudioManagerBase* audio_manager_;
std::string device_name_;
AudioParameters params_;
int bytes_per_buffer_;
base::TimeDelta buffer_duration_; // Length of each recorded buffer.
AudioInputCallback* callback_; // Valid during a recording session.
base::TimeTicks next_read_time_; // Scheduled time for next read callback.
struct sio_hdl* device_handle_; // Handle to the SNDIO PCM recording device.
std::unique_ptr<uint8_t[]> audio_buffer_; // Buffer used for reading audio data.
bool read_callback_behind_schedule_;
std::unique_ptr<AudioBus> audio_bus_;
int hw_delay_;
int sndio_rec_bufsize_;
int sndio_rec_bufsz_;
// High priority thread running RealTimeThread()
pthread_t thread_;
DISALLOW_COPY_AND_ASSIGN(SndioAudioInputStream);
};
} // namespace media
#endif // MEDIA_AUDIO_SNDIO_SNDIO_INPUT_H_
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