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/*
*
* Copyright (C) 2009 Christian Gmeiner
*
* This program 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.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
*/
#include <string>
using namespace std;
#include "dxr3audio-alsa.h"
#include "dxr3configdata.h"
void cAudioAlsa::openDevice()
{
if (open)
return;
// generate alsa card name
int card = cDxr3ConfigData::Instance().GetDxr3Card();
string cardname = "EM8300";
if (card > 0) {
cardname.append("_" + card);
}
string device = "default:CARD=" + cardname;
dsyslog("[dxr3-audio-alsa] opening device %s", device.c_str());
int err = snd_pcm_open(&handle, device.c_str(), SND_PCM_STREAM_PLAYBACK, 0);
if (err < 0) {
esyslog("[dxr3-audio-alsa] Playback open error: %s", snd_strerror(err));
exit(1);
}
open = true;
}
void cAudioAlsa::releaseDevice()
{
if (!open)
return;
if (handle) {
snd_pcm_drain(handle);
snd_pcm_close(handle);
handle = NULL;
}
open = false;
}
void cAudioAlsa::setup(const SampleContext& ctx)
{
// look if ctx is different
if (curContext.channels == ctx.channels && curContext.samplerate == ctx.samplerate) {
return;
}
dsyslog("[dxr3-audio-alsa] changing samplerate to %d (old %d) ", ctx.samplerate, curContext.samplerate);
dsyslog("[dxr3-audio-alsa] changing num of channels to %d (old %d)", ctx.channels, curContext.channels);
snd_pcm_hw_params_t* alsa_hwparams;
snd_pcm_hw_params_alloca(&alsa_hwparams);
int err = snd_pcm_hw_params_any(handle, alsa_hwparams);
if (err < 0) {
esyslog("[dxr3-audio-alsa] Broken config for this PCM: no configurations available");
exit(1);
}
// set access type
err = snd_pcm_hw_params_set_access(handle, alsa_hwparams, SND_PCM_ACCESS_RW_INTERLEAVED);
if (err < 0) {
esyslog("[dxr3-audio-alsa] Unable to set access type: %s", snd_strerror(err));
}
// set format
err = snd_pcm_hw_params_set_format(handle, alsa_hwparams, SND_PCM_FORMAT_S16_LE);
if (err < 0) {
esyslog("[dxr3-audio-alsa] Unable to set format: %s", snd_strerror(err));
}
// set channels
err = snd_pcm_hw_params_set_channels(handle, alsa_hwparams, ctx.channels);
if (err < 0) {
esyslog("[dxr3-audio-alsa] Unable to set channels %d: %s", ctx.channels, snd_strerror(err));
}
// set samplerate
err = snd_pcm_hw_params_set_rate_near(handle, alsa_hwparams, (unsigned int *)&ctx.samplerate, NULL);
if (err < 0) {
esyslog("[dxr3-audio-alsa] Unable to set samplerate %d: %s", ctx.samplerate, snd_strerror(err));
}
if (snd_pcm_state(handle) == SND_PCM_STATE_RUNNING) {
if ((err = snd_pcm_drain(handle)) < 0) {
esyslog("[dxr3-audio-alsa] Cannot drain (%s); will try to set parameters anyway\n", snd_strerror(err));
}
}
// set hardware pararmeters
err = snd_pcm_hw_params(handle, alsa_hwparams);
if (err < 0) {
esyslog("[dxr3-audio-alsa] Unable to set hw pararmeters: %s", snd_strerror(err));
}
// prepare for playback
err = snd_pcm_prepare(handle);
if (err < 0) {
esyslog("[dxr3-audio-alsa] Cannot prepare audio interface for use: %s", snd_strerror(err));
}
curContext.channels = ctx.channels;
curContext.samplerate = ctx.samplerate;
bytesFrame = snd_pcm_format_physical_width(SND_PCM_FORMAT_S16_LE) / 8;
bytesFrame *= curContext.channels;
}
void cAudioAlsa::write(uchar* data, size_t size)
{
snd_pcm_uframes_t frames = size / bytesFrame;
if (frames == 0) {
dsyslog("[dxr3-audio-alsa] no frames");
return;
}
uchar *output_samples = data;
snd_pcm_sframes_t res = 0;
while (frames > 0) {
res = snd_pcm_writei(handle, output_samples, frames);
if (res == -EAGAIN) {
snd_pcm_wait(handle, 500);
} else if (res == -EINTR) {
// nothing to do
res = 0;
} else if (res == -EPIPE) {
Xrun();
} else if (res == -ESTRPIPE) {
// suspend
dsyslog("[dxr3-audio-alsa] pcm in suspend");
while ((res = snd_pcm_resume(handle)) == -EAGAIN) {
sleep(1);
}
}
if (res > 0) {
output_samples += res * bytesFrame;
frames -= res;
}
}
}
void cAudioAlsa::setAudioMode(AudioMode mode)
{
}
void cAudioAlsa::Xrun()
{
int res;
snd_pcm_status_alloca(&status);
dsyslog("[dxr3-audio-alsa] Xrun");
res = snd_pcm_status(handle, status);
if (res < 0) {
esyslog("[dxr3-audio-alsa]: Xrun status error: %s FATAL exiting", snd_strerror(res));
exit(EXIT_FAILURE);
}
if (snd_pcm_status_get_state(status) == SND_PCM_STATE_XRUN) {
res = snd_pcm_prepare(handle);
if (res < 0) {
esyslog("[dxr3-audio-alsa]: Xrun prepare error: %s FATAL exiting", snd_strerror(res));
exit(EXIT_FAILURE);
}
return; // ok, data should be accepted again
}
esyslog("[dxr3-audio-alsa]: read/write error FATAL exiting");
exit(-1);
}
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