media/audio/pulse/pulse_util.h

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef MEDIA_AUDIO_PULSE_PULSE_UTIL_H_
   6 #define MEDIA_AUDIO_PULSE_PULSE_UTIL_H_
   7
   8 #include <pulse/pulseaudio.h>
   9
  10 #include "base/basictypes.h"
  11 #include "media/audio/audio_device_name.h"
  12 #include "media/base/channel_layout.h"
  13
  14 namespace media {
  15
  16 class AudioParameters;
  17
  18 namespace pulse {
  19
  20 // A helper class that acquires pa_threaded_mainloop_lock() while in scope.
  21 class AutoPulseLock {
  22  public:
  23   explicit AutoPulseLock(pa_threaded_mainloop* pa_mainloop)
  24       : pa_mainloop_(pa_mainloop) {
  25     pa_threaded_mainloop_lock(pa_mainloop_);
  26   }
  27
  28   ~AutoPulseLock() {
  29     pa_threaded_mainloop_unlock(pa_mainloop_);
  30   }
  31
  32  private:
  33   pa_threaded_mainloop* pa_mainloop_;
  34   DISALLOW_COPY_AND_ASSIGN(AutoPulseLock);
  35 };
  36
  37 // Triggers pa_threaded_mainloop_signal() to avoid deadlocks.
  38 void StreamSuccessCallback(pa_stream* s, int error, void* mainloop);
  39 void ContextStateCallback(pa_context* context, void* mainloop);
  40
  41 pa_sample_format_t BitsToPASampleFormat(int bits_per_sample);
  42
  43 pa_channel_map ChannelLayoutToPAChannelMap(ChannelLayout channel_layout);
  44
  45 void WaitForOperationCompletion(pa_threaded_mainloop* mainloop,
  46                                 pa_operation* operation);
  47
  48 int GetHardwareLatencyInBytes(pa_stream* stream,
  49                               int sample_rate,
  50                               int bytes_per_frame);
  51
  52 // Create a recording stream for the threaded mainloop, return true if success,
  53 // otherwise false. |mainloop| and |context| have to be from a valid Pulse
  54 // threaded mainloop and the handle of the created stream will be returned by
  55 // |stream|.
  56 bool CreateInputStream(pa_threaded_mainloop* mainloop,
  57                        pa_context* context,
  58                        pa_stream** stream,
  59                        const AudioParameters& params,
  60                        const std::string& device_id,
  61                        pa_stream_notify_cb_t stream_callback,
  62                        void* user_data);
  63
  64 // Create a playback stream for the threaded mainloop, return true if success,
  65 // otherwise false. This function will create a new Pulse threaded mainloop,
  66 // and the handles of the mainloop, context and stream will be returned by
  67 // |mainloop|, |context| and |stream|.
  68 bool CreateOutputStream(pa_threaded_mainloop** mainloop,
  69                         pa_context** context,
  70                         pa_stream** stream,
  71                         const AudioParameters& params,
  72                         const std::string& device_id,
  73                         const std::string& app_name,
  74                         pa_stream_notify_cb_t stream_callback,
  75                         pa_stream_request_cb_t write_callback,
  76                         void* user_data);
  77
  78 }  // namespace pulse
  79
  80 }  // namespace media
  81
  82 #endif  // MEDIA_AUDIO_PULSE_PULSE_UTIL_H_