path: root/src/device.cc

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set et sw=2 ts=2: */
/***************************************************************************
 *            device.cc
 *
 *  Wed Sep 24 08:54:47 CEST 2014
 *  Copyright 2014 Bent Bisballe Nyeng
 *  deva@aasimon.org
 ****************************************************************************/

/*
 *  This file is part of LibAudioIO.
 *
 *  LibAudioIO is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU Lesser General Public
 *  License as published by the Free Software Foundation; either
 *  version 2.1 of the License, or (at your option) any later version.
 *  
 *  LibAudioIO is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 *  Lesser General Public License for more details.
 *  
 *  You should have received a copy of the GNU Lesser General Public
 *  License along with LibAudioIO; if not, write to the Free Software
 *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */
#include "device.h"

Device::Device(std::string device)
{
  card = device;
}

Device::~Device()
{
}

std::vector<std::string> Device::mixerNames()
{
  std::vector<std::string> mlist;

	int err;
	snd_mixer_t *handle;
	snd_mixer_selem_id_t *sid;
	snd_mixer_elem_t *elem;
	snd_mixer_selem_id_alloca(&sid);
	
	if((err = snd_mixer_open(&handle, 0)) < 0) {
		printf("Mixer %s open error: %s", card.c_str(), snd_strerror(err));
		return mlist;
	}

	if((err = snd_mixer_attach(handle, card.c_str())) < 0) {
		printf("Mixer attach %s error: %s", card.c_str(), snd_strerror(err));
		snd_mixer_close(handle);
		return mlist;
	}

	if((err = snd_mixer_selem_register(handle, NULL, NULL)) < 0) {
		printf("Mixer register error: %s", snd_strerror(err));
		snd_mixer_close(handle);
		return mlist;
	}
	err = snd_mixer_load(handle);
	if (err < 0) {
		printf("Mixer %s load error: %s", card.c_str(), snd_strerror(err));
		snd_mixer_close(handle);
		return mlist;
	}
	for(elem = snd_mixer_first_elem(handle);
      elem;
      elem = snd_mixer_elem_next(elem)) {
		snd_mixer_selem_get_id(elem, sid);
		if(snd_mixer_selem_is_active(elem) == 0) continue;

    char cname[256];
    snprintf(cname, sizeof(cname), "'%s',%i",
             snd_mixer_selem_id_get_name(sid),
             snd_mixer_selem_id_get_index(sid));

    mlist.push_back(cname);
	}

	snd_mixer_close(handle);

  return mlist;
}

Mixer *Device::getMixer(std::string name)
{
	int err;
	snd_mixer_t *handle;
	snd_mixer_selem_id_t *sid;
	snd_mixer_elem_t *elem;
	snd_mixer_selem_id_alloca(&sid);
	
	if((err = snd_mixer_open(&handle, 0)) < 0) {
		printf("Mixer %s open error: %s", card.c_str(), snd_strerror(err));
		return NULL;
	}

	if((err = snd_mixer_attach(handle, card.c_str())) < 0) {
		printf("Mixer attach %s error: %s", card.c_str(), snd_strerror(err));
		snd_mixer_close(handle);
		return NULL;
	}

	if((err = snd_mixer_selem_register(handle, NULL, NULL)) < 0) {
		printf("Mixer register error: %s", snd_strerror(err));
		snd_mixer_close(handle);
		return NULL;
	}
	err = snd_mixer_load(handle);
	if (err < 0) {
		printf("Mixer %s load error: %s", card.c_str(), snd_strerror(err));
		snd_mixer_close(handle);
		return NULL;
	}
	for(elem = snd_mixer_first_elem(handle);
      elem;
      elem = snd_mixer_elem_next(elem)) {
		snd_mixer_selem_get_id(elem, sid);
		if(snd_mixer_selem_is_active(elem) == 0) continue;

    char cname[256];
    snprintf(cname, sizeof(cname), "'%s',%i",
             snd_mixer_selem_id_get_name(sid),
             snd_mixer_selem_id_get_index(sid));

    if(std::string(cname) == name) {
      // NOTE: The Mixer object takes ownership of 'handle' which closed in
      // its destructor.
      return new Mixer(handle, elem);
    }
	}

	snd_mixer_close(handle);

  printf("Mixer element \"%s\" not found.\n", name.c_str());

  return NULL;
}

static int pcm_init(snd_pcm_t *handle, unsigned int *samplerate,
                    unsigned int channels, snd_pcm_uframes_t *frames)
{
  int err;
  snd_pcm_hw_params_t *params;

  // Allocate a hardware parameters object.
  snd_pcm_hw_params_alloca(&params);

  // Fill it in with default values.
  err = snd_pcm_hw_params_any(handle, params);
  if(err) {
    printf("snd_pcm_hw_params_any: %s, %d\n", snd_strerror(err), err);
    return 1;
  }

  // Interleaved mode
  err = snd_pcm_hw_params_set_access(handle, params,
                                     SND_PCM_ACCESS_RW_INTERLEAVED);
  if(err) {
    printf("snd_pcm_hw_params_set_access: %s, %d\n", snd_strerror(err), err);
    return 1;
  }

  // Signed 16-bit little-endian format
  err = snd_pcm_hw_params_set_format(handle, params, SND_PCM_FORMAT_S16_LE);
  if(err) {
    printf("snd_pcm_hw_params_set_format: %s, %d\n", snd_strerror(err), err);
    return 1;
  }

  // Set channels (stereo/mono)
  err = snd_pcm_hw_params_set_channels(handle, params, channels);
  if(err) {
    printf("snd_pcm_hw_params_set_channels: %s, %d\n", snd_strerror(err), err);
    return 1;
  }

  // dir: -1 := exact or first below
  //       0 := exact (error if not?)
  //       1 := exact or first above
  int dir = 1;

  // Set sampling rate
  err = snd_pcm_hw_params_set_rate_near(handle, params, samplerate, &dir);
  if(err) {
    printf("snd_pcm_hw_params_set_rate_near: %s, %d\n", snd_strerror(err), err);
    return 1;
  }

  // printf("Actual samplerate: %d\n", samplerate);

  err = snd_pcm_hw_params_set_period_size_near(handle, params, frames, &dir);
  if(err) {
    printf("snd_pcm_hw_params_set_period_size_near: %s, %d\n",
           snd_strerror(err), err);
    return 1;
  }

  // printf("Actual buffersize: %d\n", (int)frames);
 
  // Write the parameters to the driver
  err = snd_pcm_hw_params(handle, params);
  if(err) {
    printf("snd_pcm_hw_params: %s, %d\n",
           snd_strerror(err), err);
    return 1;
  }

  return 0;
}

Source *Device::getSource(std::string name, unsigned int samplerate,
                          unsigned int channels)
{
  int open_mode = 0;
  //open_mode |= SND_PCM_NONBLOCK;
  //open_mode |= SND_PCM_NO_AUTO_RESAMPLE;
  //open_mode |= SND_PCM_NO_AUTO_CHANNELS;
  //open_mode |= SND_PCM_NO_AUTO_FORMAT;
  //open_mode |= SND_PCM_NO_SOFTVOL;

	int err;
  snd_pcm_t *handle;

  // Open PCM device for recording (capture).
  err = snd_pcm_open(&handle, name.c_str(), SND_PCM_STREAM_CAPTURE,
                     open_mode);
  if(err) {
    printf("snd_pcm_open: %s, %d\n", snd_strerror(err), err);
    return NULL;
  }

  snd_pcm_uframes_t frames = 512;
  if(pcm_init(handle, &samplerate, channels, &frames)) return NULL;

  return new Source(handle, samplerate, channels, frames);
}

Sink *Device::getSink(std::string name, unsigned int samplerate,
                      unsigned int channels)
{
  int open_mode = 0;
  //open_mode |= SND_PCM_NONBLOCK;
  //open_mode |= SND_PCM_NO_AUTO_RESAMPLE;
  //open_mode |= SND_PCM_NO_AUTO_CHANNELS;
  //open_mode |= SND_PCM_NO_AUTO_FORMAT;
  //open_mode |= SND_PCM_NO_SOFTVOL;

	int err;
  snd_pcm_t *handle;

  // Open PCM device for recording (capture).
  err = snd_pcm_open(&handle, name.c_str(), SND_PCM_STREAM_PLAYBACK,
                     open_mode);
  if(err) {
    printf("snd_pcm_open: %s, %d\n", snd_strerror(err), err);
    return NULL;
  }
  
  snd_pcm_uframes_t frames = 2048;
  if(pcm_init(handle, &samplerate, channels, &frames)) return NULL;

  return new Sink(handle, samplerate, channels, frames);
}