media/audio/alsa/alsa_wrapper.h

   1 // Copyright 2013 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 // AlsaWrapper is a simple stateless class that wraps the alsa library commands
   6 // we want to use.  It's purpose is to allow injection of a mock so that the
   7 // higher level code is testable.
   8
   9 #ifndef MEDIA_AUDIO_ALSA_ALSA_WRAPPER_H_
  10 #define MEDIA_AUDIO_ALSA_ALSA_WRAPPER_H_
  11
  12 #include <alsa/asoundlib.h>
  13
  14 #include "base/basictypes.h"
  15 #include "media/base/media_export.h"
  16
  17 namespace media {
  18
  19 class MEDIA_EXPORT AlsaWrapper {
  20  public:
  21   AlsaWrapper();
  22   virtual ~AlsaWrapper();
  23
  24   virtual int DeviceNameHint(int card, const char* iface, void*** hints);
  25   virtual char* DeviceNameGetHint(const void* hint, const char* id);
  26   virtual int DeviceNameFreeHint(void** hints);
  27   virtual int CardNext(int* rcard);
  28
  29   virtual int PcmOpen(snd_pcm_t** handle, const char* name,
  30                       snd_pcm_stream_t stream, int mode);
  31   virtual int PcmClose(snd_pcm_t* handle);
  32   virtual int PcmPrepare(snd_pcm_t* handle);
  33   virtual int PcmDrop(snd_pcm_t* handle);
  34   virtual int PcmDelay(snd_pcm_t* handle, snd_pcm_sframes_t* delay);
  35   virtual snd_pcm_sframes_t PcmWritei(snd_pcm_t* handle,
  36                                       const void* buffer,
  37                                       snd_pcm_uframes_t size);
  38   virtual snd_pcm_sframes_t PcmReadi(snd_pcm_t* handle,
  39                                      void* buffer,
  40                                      snd_pcm_uframes_t size);
  41   virtual int PcmRecover(snd_pcm_t* handle, int err, int silent);
  42   virtual int PcmSetParams(snd_pcm_t* handle, snd_pcm_format_t format,
  43                            snd_pcm_access_t access, unsigned int channels,
  44                            unsigned int rate, int soft_resample,
  45                            unsigned int latency);
  46   virtual int PcmGetParams(snd_pcm_t* handle, snd_pcm_uframes_t* buffer_size,
  47                            snd_pcm_uframes_t* period_size);
  48   virtual const char* PcmName(snd_pcm_t* handle);
  49   virtual snd_pcm_sframes_t PcmAvailUpdate(snd_pcm_t* handle);
  50   virtual snd_pcm_state_t PcmState(snd_pcm_t* handle);
  51   virtual int PcmStart(snd_pcm_t* handle);
  52
  53   virtual int MixerOpen(snd_mixer_t** mixer, int mode);
  54   virtual int MixerAttach(snd_mixer_t* mixer, const char* name);
  55   virtual int MixerElementRegister(snd_mixer_t* mixer,
  56                                    struct snd_mixer_selem_regopt* options,
  57                                    snd_mixer_class_t** classp);
  58   virtual void MixerFree(snd_mixer_t* mixer);
  59   virtual int MixerDetach(snd_mixer_t* mixer, const char* name);
  60   virtual int MixerClose(snd_mixer_t* mixer);
  61   virtual int MixerLoad(snd_mixer_t* mixer);
  62   virtual snd_mixer_elem_t* MixerFirstElem(snd_mixer_t* mixer);
  63   virtual snd_mixer_elem_t* MixerNextElem(snd_mixer_elem_t* elem);
  64   virtual int MixerSelemIsActive(snd_mixer_elem_t* elem);
  65   virtual const char* MixerSelemName(snd_mixer_elem_t* elem);
  66   virtual int MixerSelemSetCaptureVolumeAll(snd_mixer_elem_t* elem, long value);
  67   virtual int MixerSelemGetCaptureVolume(snd_mixer_elem_t* elem,
  68                                          snd_mixer_selem_channel_id_t channel,
  69                                          long* value);
  70   virtual int MixerSelemHasCaptureVolume(snd_mixer_elem_t* elem);
  71   virtual int MixerSelemGetCaptureVolumeRange(snd_mixer_elem_t* elem,
  72                                               long* min, long* max);
  73
  74   virtual const char* StrError(int errnum);
  75
  76  private:
  77   int ConfigureHwParams(snd_pcm_t* handle, snd_pcm_hw_params_t* hw_params,
  78                         snd_pcm_format_t format, snd_pcm_access_t access,
  79                         unsigned int channels, unsigned int rate,
  80                         int soft_resample, unsigned int latency);
  81   DISALLOW_COPY_AND_ASSIGN(AlsaWrapper);
  82 };
  83
  84 }  // namespace media
  85
  86 #endif  // MEDIA_AUDIO_ALSA_ALSA_WRAPPER_H_