www/chromium: add SNDIO option

PR:		220230
Submitted by:	tobik

1 files changed, 108 insertions, 0 deletions

diff --git a/www/chromium/files/sndio_input.h b/www/chromium/files/sndio_input.h
new file mode 100644
index 000000000000..b354f66fd55a
--- /dev/null
+++ b/www/chromium/files/sndio_input.h
@@ -0,0 +1,108 @@
+// 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_