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/* this file is a part of amp software, (C) tomislav uzelac 1996,1997
Origional code by: tomislav uzelac
Modified by:
* Dan Nelson - BSD mods.
* Andrew Richards - moved code from audio.c and added mixer support etc
* Martin Vogt
*/
/* Support for Linux and BSD sound devices */
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/ioctl.h>
#include <fcntl.h>
#include <unistd.h>
#include <stdio.h>
#include "audioIO.h"
#include <stdlib.h>
#include <stdio.h>
//
// Why all these different system cannot make a standard where this
// soundcard.h file is ?
//
#if defined(HAVE_SYS_SOUNDCARD_H)
#undef AUSIZ
#undef HAVE_SYS_SOUNDCARD_H
#include <sys/soundcard.h>
#elif defined(HAVE_MACHINE_SOUNDCARD_H)
#undef AUSIZ
#include <machine/soundcard.h>
#elif defined(__NetBSD__)
#undef AUSIZ
#include <soundcard.h>
#else
// fallback:
#include <linux/soundcard.h>
#endif
/* optimal fragment size */
int AUSIZ = 0;
// declare these static to effectively isolate the audio device
static int audio_fd;
static int mixer_fd;
static int volumeIoctl;
int audioConstruct() {
audio_fd=-1;
mixer_fd=-1;
return true;
}
void audioDestruct() {
}
/*
should open the audio device, perform any special initialization
*/
int audioOpen() {
audio_fd = open ("/dev/dsp", O_WRONLY, 0);
if (audio_fd < 0) {
perror("Unable to open the audio");
}
// Ok here something important if your programm forks:
if (audio_fd > 0) {
if (fcntl(audio_fd,F_SETFD,true) < 0) {
perror("fcntl socket");exit(1);
}
}
return (audio_fd > 0);
}
inline void audioFlush() {
if (ioctl(audio_fd, SNDCTL_DSP_RESET, 0) == -1)
perror("Unable to reset audio device\n");
}
/*
should close the audio device and perform any special shutdown
*/
void audioClose() {
audioFlush();
if (close(audio_fd) < 0) {
perror("error close audiodevice:");
}
}
void audioInit(int sampleSize,int frequency, int stereo, int sign, int big) {
if( sign == 0 )
{
fprintf(stderr,
"%s, %d: expecting signed audio data, "
"initialized unsigned (ignored)\n",
__FILE__, __LINE__ );
}
if( big != 0 )
{
fprintf(stderr,
"%s, %d: expecting little endian audio data, "
"initialized big endian (ignored)\n",
__FILE__, __LINE__ );
}
int play_format=AFMT_S16_LE;
if (sampleSize == 8) {
play_format=AFMT_S8;
}
ioctl(audio_fd,SNDCTL_DSP_RESET,NULL);
if (ioctl(audio_fd, SNDCTL_DSP_SETFMT,&play_format) < 0) {
perror("Unable to set required audio format\n");
}
/* Set 1 or 2 channels */
stereo=(stereo ? 1 : 0);
if (ioctl(audio_fd, SNDCTL_DSP_STEREO, &stereo) < 0) {
perror("Unable to set stereo/mono\n");
exit(0);
}
/* Set the output frequency */
if (ioctl(audio_fd, SNDCTL_DSP_SPEED, &frequency) < 0) {
perror("Unable to set frequency");
exit(0);
}
if (ioctl(audio_fd, SNDCTL_DSP_GETBLKSIZE, &AUSIZ) == -1) {
perror("Unable to get fragment size\n");
exit(0);
}
}
int getAudioBufferSize() {
struct audio_buf_info buf_info;
int buf=1024*65;
if (ioctl(audio_fd,SNDCTL_DSP_GETOSPACE,&buf_info) == -1) {
perror("ioctl getAudioBufferSize using default");
} else {
buf=buf_info.bytes;
}
return buf;
}
int mixerOpen() {
int supportedMixers;
if ((mixer_fd=open("/dev/mixer",O_RDWR)) == -1) {
perror("Unable to open mixer device");
}
// Ok here something important if your programm forks:
if (mixer_fd > 0) {
if (fcntl(mixer_fd,F_SETFD,true) < 0) {
perror("fcntl socket");exit(1);
}
}
if (ioctl(mixer_fd, SOUND_MIXER_READ_DEVMASK, &supportedMixers) == -1){
perror("Unable to get mixer info assuming master volume");
volumeIoctl=SOUND_MIXER_WRITE_VOLUME;
} else {
if ((supportedMixers & SOUND_MASK_PCM) != 0)
volumeIoctl=SOUND_MIXER_WRITE_PCM;
else
volumeIoctl=0;
}
return (mixer_fd > 0);
}
void mixerClose() {
if (mixer_fd != -1) {
close(mixer_fd);
}
}
/*
only code this if your system can change the volume while
playing
*/
void mixerSetVolume(int leftVolume,int rightVolume) {
int volume;
volume=leftVolume+(rightVolume<<8);
if ((mixer_fd != -1) && (volumeIoctl!=0)) {
if (ioctl(mixer_fd, volumeIoctl, &volume) < 0) {
perror("Unable to set sound volume");
}
}
}
int audioWrite(char *buffer, int count) {
return(write(audio_fd,buffer,count));
}
int getAudioFd() {
return(audio_fd);
}
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