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/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
*
* Copyright (C) 2002 Dave Chapman
*
* oss_sound - a sound driver for Linux (and others?) OSS audio
*
* All files in this archive are subject to the GNU General Public License.
* See the file COPYING in the source tree root for full license agreement.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
#include <stdio.h>
#include <fcntl.h>
#include <linux/soundcard.h>
#include "../common/sound.h"
/* We want to use the "real" open in this file */
#undef open
int init_sound(sound_t* sound) {
sound->fd=open("/dev/dsp", O_WRONLY);
sound->freq=-1;
sound->channels=-1;
if (sound->fd <= 0) {
fprintf(stderr,"Can not open /dev/dsp - simulating sound output\n");
sound->fd=0;
}
}
int config_sound(sound_t* sound, int sound_freq, int channels) {
int format=AFMT_U16_LE;
int setting=0x000C000D; // 12 fragments size 8kb ? WHAT IS THIS?
sound->freq=sound_freq;
sound->channels=channels;
if (sound->fd) {
if (ioctl(sound->fd,SNDCTL_DSP_SETFRAGMENT,&setting)==-1) {
perror("SNDCTL_DSP_SETFRAGMENT");
}
if (ioctl(sound->fd,SNDCTL_DSP_CHANNELS,&channels)==-1) {
perror("SNDCTL_DSP_STEREO");
}
if (channels==0) { fprintf(stderr,"Warning, only mono supported\n"); }
if (ioctl(sound->fd,SNDCTL_DSP_SETFMT,&format)==-1) {
perror("SNDCTL_DSP_SETFMT");
}
if (ioctl(sound->fd,SNDCTL_DSP_SPEED,&sound_freq)==-1) {
perror("SNDCTL_DSP_SPEED");
}
}
}
int output_sound(sound_t* sound,const void* buf, int count) {
unsigned long long t;
if (sound->fd) {
return(write(sound->fd,buf,count));
} else {
t=(unsigned int)(((unsigned int)(1000000/sound->channels)*count)/sound->freq);
// fprintf(stderr,"writing %d bytes at %d frequency - sleeping for %u microseconds\n",count,sound->freq,t);
usleep(t);
return(count);
}
}
void close_sound(sound_t* sound) {
if (sound->fd) close(sound->fd);
sound->fd=-1;
}
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