432 lines
15 KiB
C
432 lines
15 KiB
C
/*
|
|
Copyright (C) 2004-2006 Jean-Marc Valin
|
|
Copyright (C) 2006 Commonwealth Scientific and Industrial Research
|
|
Organisation (CSIRO) Australia
|
|
|
|
Redistribution and use in source and binary forms, with or without
|
|
modification, are permitted provided that the following conditions are
|
|
met:
|
|
|
|
1. Redistributions of source code must retain the above copyright notice,
|
|
this list of conditions and the following disclaimer.
|
|
|
|
2. Redistributions in binary form must reproduce the above copyright
|
|
notice, this list of conditions and the following disclaimer in the
|
|
documentation and/or other materials provided with the distribution.
|
|
|
|
3. The name of the author may not be used to endorse or promote products
|
|
derived from this software without specific prior written permission.
|
|
|
|
THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
|
|
IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
|
|
OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
|
|
DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
|
|
INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
|
|
(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
|
|
SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
|
|
STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
|
|
ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
|
|
POSSIBILITY OF SUCH DAMAGE.
|
|
*/
|
|
|
|
#include "alsa_device.h"
|
|
#include <stdlib.h>
|
|
#include <alsa/asoundlib.h>
|
|
|
|
struct AlsaDevice_ {
|
|
char *device_name;
|
|
int channels;
|
|
int period;
|
|
snd_pcm_t *capture_handle;
|
|
snd_pcm_t *playback_handle;
|
|
int readN, writeN;
|
|
struct pollfd *read_fd, *write_fd;
|
|
};
|
|
|
|
AlsaDevice *alsa_device_open(char *device_name, unsigned int rate, int channels, int period)
|
|
{
|
|
int dir;
|
|
int err;
|
|
snd_pcm_hw_params_t *hw_params;
|
|
snd_pcm_sw_params_t *sw_params;
|
|
snd_pcm_uframes_t period_size = period;
|
|
snd_pcm_uframes_t buffer_size = 2*period;
|
|
static snd_output_t *jcd_out;
|
|
AlsaDevice *dev = malloc(sizeof(*dev));
|
|
if (!dev)
|
|
return NULL;
|
|
dev->device_name = malloc(1+strlen(device_name));
|
|
if (!dev->device_name)
|
|
{
|
|
free(dev);
|
|
return NULL;
|
|
}
|
|
strcpy(dev->device_name, device_name);
|
|
dev->channels = channels;
|
|
dev->period = period;
|
|
err = snd_output_stdio_attach(&jcd_out, stdout, 0);
|
|
|
|
if ((err = snd_pcm_open (&dev->capture_handle, dev->device_name, SND_PCM_STREAM_CAPTURE, 0)) < 0) {
|
|
fprintf (stderr, "cannot open audio device %s (%s)\n",
|
|
dev->device_name,
|
|
snd_strerror (err));
|
|
assert(0);
|
|
}
|
|
|
|
if ((err = snd_pcm_hw_params_malloc (&hw_params)) < 0) {
|
|
fprintf (stderr, "cannot allocate hardware parameter structure (%s)\n",
|
|
snd_strerror (err));
|
|
assert(0);
|
|
}
|
|
|
|
if ((err = snd_pcm_hw_params_any (dev->capture_handle, hw_params)) < 0) {
|
|
fprintf (stderr, "cannot initialize hardware parameter structure (%s)\n",
|
|
snd_strerror (err));
|
|
assert(0);
|
|
}
|
|
|
|
if ((err = snd_pcm_hw_params_set_access (dev->capture_handle, hw_params, SND_PCM_ACCESS_RW_INTERLEAVED)) < 0) {
|
|
fprintf (stderr, "cannot set access type (%s)\n",
|
|
snd_strerror (err));
|
|
assert(0);
|
|
}
|
|
|
|
if ((err = snd_pcm_hw_params_set_format (dev->capture_handle, hw_params, SND_PCM_FORMAT_S16_LE)) < 0) {
|
|
fprintf (stderr, "cannot set sample format (%s)\n",
|
|
snd_strerror (err));
|
|
assert(0);
|
|
}
|
|
|
|
if ((err = snd_pcm_hw_params_set_rate_near (dev->capture_handle, hw_params, &rate, 0)) < 0) {
|
|
fprintf (stderr, "cannot set sample rate (%s)\n",
|
|
snd_strerror (err));
|
|
assert(0);
|
|
}
|
|
/*fprintf (stderr, "rate = %d\n", rate);*/
|
|
|
|
if ((err = snd_pcm_hw_params_set_channels (dev->capture_handle, hw_params, channels)) < 0) {
|
|
fprintf (stderr, "cannot set channel count (%s)\n",
|
|
snd_strerror (err));
|
|
assert(0);
|
|
}
|
|
|
|
period_size = period;
|
|
dir = 0;
|
|
if ((err = snd_pcm_hw_params_set_period_size_near (dev->capture_handle, hw_params, &period_size, &dir)) < 0) {
|
|
fprintf (stderr, "cannot set period size (%s)\n",
|
|
snd_strerror (err));
|
|
assert(0);
|
|
}
|
|
|
|
if ((err = snd_pcm_hw_params_set_periods (dev->capture_handle, hw_params, 2, 0)) < 0) {
|
|
fprintf (stderr, "cannot set number of periods (%s)\n",
|
|
snd_strerror (err));
|
|
assert(0);
|
|
}
|
|
|
|
buffer_size = period_size * 2;
|
|
dir=0;
|
|
if ((err = snd_pcm_hw_params_set_buffer_size_near (dev->capture_handle, hw_params, &buffer_size)) < 0) {
|
|
fprintf (stderr, "cannot set buffer time (%s)\n",
|
|
snd_strerror (err));
|
|
assert(0);
|
|
}
|
|
|
|
if ((err = snd_pcm_hw_params (dev->capture_handle, hw_params)) < 0) {
|
|
fprintf (stderr, "cannot set capture parameters (%s)\n",
|
|
snd_strerror (err));
|
|
assert(0);
|
|
}
|
|
/*snd_pcm_dump_setup(dev->capture_handle, jcd_out);*/
|
|
snd_pcm_hw_params_free (hw_params);
|
|
|
|
if ((err = snd_pcm_sw_params_malloc (&sw_params)) < 0) {
|
|
fprintf (stderr, "cannot allocate software parameters structure (%s)\n",
|
|
snd_strerror (err));
|
|
assert(0);
|
|
}
|
|
if ((err = snd_pcm_sw_params_current (dev->capture_handle, sw_params)) < 0) {
|
|
fprintf (stderr, "cannot initialize software parameters structure (%s)\n",
|
|
snd_strerror (err));
|
|
assert(0);
|
|
}
|
|
if ((err = snd_pcm_sw_params_set_avail_min (dev->capture_handle, sw_params, period)) < 0) {
|
|
fprintf (stderr, "cannot set minimum available count (%s)\n",
|
|
snd_strerror (err));
|
|
assert(0);
|
|
}
|
|
if ((err = snd_pcm_sw_params (dev->capture_handle, sw_params)) < 0) {
|
|
fprintf (stderr, "cannot set software parameters (%s)\n",
|
|
snd_strerror (err));
|
|
assert(0);
|
|
}
|
|
|
|
|
|
if ((err = snd_pcm_open (&dev->playback_handle, dev->device_name, SND_PCM_STREAM_PLAYBACK, 0)) < 0) {
|
|
fprintf (stderr, "cannot open audio device %s (%s)\n",
|
|
dev->device_name,
|
|
snd_strerror (err));
|
|
assert(0);
|
|
}
|
|
|
|
if ((err = snd_pcm_hw_params_malloc (&hw_params)) < 0) {
|
|
fprintf (stderr, "cannot allocate hardware parameter structure (%s)\n",
|
|
snd_strerror (err));
|
|
assert(0);
|
|
}
|
|
|
|
if ((err = snd_pcm_hw_params_any (dev->playback_handle, hw_params)) < 0) {
|
|
fprintf (stderr, "cannot initialize hardware parameter structure (%s)\n",
|
|
snd_strerror (err));
|
|
assert(0);
|
|
}
|
|
|
|
if ((err = snd_pcm_hw_params_set_access (dev->playback_handle, hw_params, SND_PCM_ACCESS_RW_INTERLEAVED)) < 0) {
|
|
fprintf (stderr, "cannot set access type (%s)\n",
|
|
snd_strerror (err));
|
|
assert(0);
|
|
}
|
|
|
|
if ((err = snd_pcm_hw_params_set_format (dev->playback_handle, hw_params, SND_PCM_FORMAT_S16_LE)) < 0) {
|
|
fprintf (stderr, "cannot set sample format (%s)\n",
|
|
snd_strerror (err));
|
|
assert(0);
|
|
}
|
|
|
|
if ((err = snd_pcm_hw_params_set_rate_near (dev->playback_handle, hw_params, &rate, 0)) < 0) {
|
|
fprintf (stderr, "cannot set sample rate (%s)\n",
|
|
snd_strerror (err));
|
|
assert(0);
|
|
}
|
|
/*fprintf (stderr, "rate = %d\n", rate);*/
|
|
|
|
if ((err = snd_pcm_hw_params_set_channels (dev->playback_handle, hw_params, channels)) < 0) {
|
|
fprintf (stderr, "cannot set channel count (%s)\n",
|
|
snd_strerror (err));
|
|
assert(0);
|
|
}
|
|
|
|
period_size = period;
|
|
dir = 0;
|
|
if ((err = snd_pcm_hw_params_set_period_size_near (dev->playback_handle, hw_params, &period_size, &dir)) < 0) {
|
|
fprintf (stderr, "cannot set period size (%s)\n",
|
|
snd_strerror (err));
|
|
assert(0);
|
|
}
|
|
if ((err = snd_pcm_hw_params_set_periods (dev->playback_handle, hw_params, 2, 0)) < 0) {
|
|
fprintf (stderr, "cannot set number of periods (%s)\n",
|
|
snd_strerror (err));
|
|
assert(0);
|
|
}
|
|
buffer_size = period_size * 2;
|
|
dir=0;
|
|
if ((err = snd_pcm_hw_params_set_buffer_size_near (dev->playback_handle, hw_params, &buffer_size)) < 0) {
|
|
fprintf (stderr, "cannot set buffer time (%s)\n",
|
|
snd_strerror (err));
|
|
assert(0);
|
|
}
|
|
|
|
|
|
if ((err = snd_pcm_hw_params (dev->playback_handle, hw_params)) < 0) {
|
|
fprintf (stderr, "cannot set playback parameters (%s)\n",
|
|
snd_strerror (err));
|
|
assert(0);
|
|
}
|
|
|
|
/*snd_pcm_dump_setup(dev->playback_handle, jcd_out);*/
|
|
snd_pcm_hw_params_free (hw_params);
|
|
|
|
|
|
if ((err = snd_pcm_sw_params_malloc (&sw_params)) < 0) {
|
|
fprintf (stderr, "cannot allocate software parameters structure (%s)\n",
|
|
snd_strerror (err));
|
|
assert(0);
|
|
}
|
|
if ((err = snd_pcm_sw_params_current (dev->playback_handle, sw_params)) < 0) {
|
|
fprintf (stderr, "cannot initialize software parameters structure (%s)\n",
|
|
snd_strerror (err));
|
|
assert(0);
|
|
}
|
|
if ((err = snd_pcm_sw_params_set_avail_min (dev->playback_handle, sw_params, period)) < 0) {
|
|
fprintf (stderr, "cannot set minimum available count (%s)\n",
|
|
snd_strerror (err));
|
|
assert(0);
|
|
}
|
|
if ((err = snd_pcm_sw_params_set_start_threshold (dev->playback_handle, sw_params, period)) < 0) {
|
|
fprintf (stderr, "cannot set start mode (%s)\n",
|
|
snd_strerror (err));
|
|
assert(0);
|
|
}
|
|
if ((err = snd_pcm_sw_params (dev->playback_handle, sw_params)) < 0) {
|
|
fprintf (stderr, "cannot set software parameters (%s)\n",
|
|
snd_strerror (err));
|
|
assert(0);
|
|
}
|
|
|
|
|
|
snd_pcm_link(dev->capture_handle, dev->playback_handle);
|
|
if ((err = snd_pcm_prepare (dev->capture_handle)) < 0) {
|
|
fprintf (stderr, "cannot prepare audio interface for use (%s)\n",
|
|
snd_strerror (err));
|
|
assert(0);
|
|
}
|
|
if ((err = snd_pcm_prepare (dev->playback_handle)) < 0) {
|
|
fprintf (stderr, "cannot prepare audio interface for use (%s)\n",
|
|
snd_strerror (err));
|
|
assert(0);
|
|
}
|
|
|
|
dev->readN = snd_pcm_poll_descriptors_count(dev->capture_handle);
|
|
dev->writeN = snd_pcm_poll_descriptors_count(dev->playback_handle);
|
|
|
|
dev->read_fd = malloc(dev->readN*sizeof(*dev->read_fd));
|
|
/*printf ("descriptors: %d %d\n", dev->readN, dev->writeN);*/
|
|
if (snd_pcm_poll_descriptors(dev->capture_handle, dev->read_fd, dev->readN) != dev->readN)
|
|
{
|
|
fprintf (stderr, "cannot obtain capture file descriptors (%s)\n",
|
|
snd_strerror (err));
|
|
assert(0);
|
|
}
|
|
|
|
dev->write_fd = malloc(dev->writeN*sizeof(*dev->read_fd));
|
|
if (snd_pcm_poll_descriptors(dev->playback_handle, dev->write_fd, dev->writeN) != dev->writeN)
|
|
{
|
|
fprintf (stderr, "cannot obtain playback file descriptors (%s)\n",
|
|
snd_strerror (err));
|
|
assert(0);
|
|
}
|
|
return dev;
|
|
}
|
|
|
|
void alsa_device_close(AlsaDevice *dev)
|
|
{
|
|
snd_pcm_close(dev->capture_handle);
|
|
snd_pcm_close(dev->playback_handle);
|
|
free(dev->device_name);
|
|
free(dev);
|
|
}
|
|
|
|
int alsa_device_read(AlsaDevice *dev, short *pcm, int len)
|
|
{
|
|
int err;
|
|
/*fprintf (stderr, "-");*/
|
|
if ((err = snd_pcm_readi (dev->capture_handle, pcm, len)) != len)
|
|
{
|
|
if (err<0)
|
|
{
|
|
//fprintf(stderr, "error %d, EPIPE = %d\n", err, EPIPE);
|
|
if (err == -EPIPE)
|
|
{
|
|
fprintf (stderr, "An overrun has occured, reseting capture\n");
|
|
} else
|
|
{
|
|
fprintf (stderr, "read from audio interface failed (%s)\n",
|
|
snd_strerror (err));
|
|
}
|
|
if ((err = snd_pcm_prepare (dev->capture_handle)) < 0)
|
|
{
|
|
fprintf (stderr, "cannot prepare audio interface for use (%s)\n",
|
|
snd_strerror (err));
|
|
}
|
|
if ((err = snd_pcm_start (dev->capture_handle)) < 0)
|
|
{
|
|
fprintf (stderr, "cannot prepare audio interface for use (%s)\n",
|
|
snd_strerror (err));
|
|
}
|
|
/*alsa_device_read(dev,pcm,len);*/
|
|
} else {
|
|
fprintf (stderr, "Couldn't read as many samples as I wanted (%d instead of %d)\n", err, len);
|
|
}
|
|
return 1;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
int alsa_device_write(AlsaDevice *dev, const short *pcm, int len)
|
|
{
|
|
int err;
|
|
/*fprintf (stderr, "+");*/
|
|
if ((err = snd_pcm_writei (dev->playback_handle, pcm, len)) != len)
|
|
{
|
|
if (err<0)
|
|
{
|
|
if (err == -EPIPE)
|
|
{
|
|
fprintf (stderr, "An underrun has occured, reseting playback, len=%d\n", len);
|
|
} else
|
|
{
|
|
fprintf (stderr, "write to audio interface failed (%s)\n",
|
|
snd_strerror (err));
|
|
}
|
|
if ((err = snd_pcm_prepare (dev->playback_handle)) < 0)
|
|
{
|
|
fprintf (stderr, "cannot prepare audio interface for use (%s)\n",
|
|
snd_strerror (err));
|
|
}
|
|
} else {
|
|
fprintf (stderr, "Couldn't write as many samples as I wanted (%d instead of %d)\n", err, len);
|
|
}
|
|
/*alsa_device_write(dev,pcm,len);*/
|
|
return 1;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
int alsa_device_capture_ready(AlsaDevice *dev, struct pollfd *pfds, unsigned int nfds)
|
|
{
|
|
unsigned short revents=0;
|
|
int err;
|
|
if ((err = snd_pcm_poll_descriptors_revents(dev->capture_handle, pfds, dev->readN, &revents)) < 0)
|
|
{
|
|
//cerr << "error in snd_pcm_poll_descriptors_revents for capture: " << snd_strerror (err) << endl;
|
|
//FIXME: This is a kludge
|
|
fprintf (stderr, "error in alsa_device_capture_ready: %s\n", snd_strerror (err));
|
|
return pfds[0].revents & POLLIN;
|
|
}
|
|
//cerr << (revents & POLLERR) << endl;
|
|
return revents & POLLIN;
|
|
}
|
|
|
|
int alsa_device_playback_ready(AlsaDevice *dev, struct pollfd *pfds, unsigned int nfds)
|
|
{
|
|
unsigned short revents=0;
|
|
int err;
|
|
if ((err = snd_pcm_poll_descriptors_revents(dev->playback_handle, pfds+dev->readN, dev->writeN, &revents)) < 0)
|
|
{
|
|
//cerr << "error in snd_pcm_poll_descriptors_revents for playback: " << snd_strerror (err) << endl;
|
|
//FIXME: This is a kludge
|
|
fprintf (stderr, "error in alsa_device_playback_ready: %s\n", snd_strerror (err));
|
|
return pfds[1].revents & POLLOUT;
|
|
}
|
|
//cerr << (revents & POLLERR) << endl;
|
|
return revents & POLLOUT;
|
|
}
|
|
|
|
void alsa_device_start(AlsaDevice *dev)
|
|
{
|
|
int i;
|
|
short pcm[dev->period*dev->channels];
|
|
for (i=0;i<dev->period*dev->channels;i++)
|
|
pcm[i] = 0;
|
|
alsa_device_write(dev, pcm, dev->period);
|
|
alsa_device_write(dev, pcm, dev->period);
|
|
snd_pcm_start(dev->capture_handle);
|
|
snd_pcm_start(dev->playback_handle);
|
|
}
|
|
|
|
int alsa_device_nfds(AlsaDevice *dev)
|
|
{
|
|
return dev->writeN+dev->readN;
|
|
}
|
|
|
|
void alsa_device_getfds(AlsaDevice *dev, struct pollfd *pfds, unsigned int nfds)
|
|
{
|
|
int i;
|
|
assert (nfds >= dev->writeN+dev->readN);
|
|
for (i=0;i<dev->readN;i++)
|
|
pfds[i] = dev->read_fd[i];
|
|
for (i=0;i<dev->writeN;i++)
|
|
pfds[i+dev->readN] = dev->write_fd[i];
|
|
}
|