conterm/kern/devaudio-sun.c

269 lines
4.7 KiB
C

/*
* Sun
*/
#include <sys/ioctl.h>
#include <sys/audio.h>
#include "u.h"
#include "lib.h"
#include "dat.h"
#include "fns.h"
#include "error.h"
#include "devaudio.h"
enum
{
Channels = 2,
Rate = 44100,
Bits = 16,
};
static char* afn = 0;
static char* cfn = 0;
static int afd = -1;
static int cfd = -1;
static int speed = Rate;
static int needswap = -1;
static void
audiodevinit(void)
{
uchar *p;
ushort leorder;
if ((afn = getenv("AUDIODEV")) == nil)
afn = "/dev/audio";
cfn = (char*)malloc(strlen(afn) + 3 + 1);
if(cfn == nil)
panic("out of memory");
strcpy(cfn, afn);
strcat(cfn, "ctl");
/*
* Plan 9 /dev/audio is always little endian;
* solaris /dev/audio seems to expect native byte order,
* so on big endian machine (like sparc) we have to swap.
*/
leorder = (ushort) 0x0100;
p = (uchar*)&leorder;
if (p[0] == 0 && p[1] == 1) {
/* little-endian: nothing to do */
needswap = 0;
} else {
/* big-endian: translate Plan 9 little-endian */
needswap = 1;
}
}
/* maybe this should return -1 instead of sysfatal */
void
audiodevopen(void)
{
audio_info_t info;
struct audio_device ad;
if (afn == nil || cfn == nil)
audiodevinit();
if((afd = open(afn, O_WRONLY)) < 0)
goto err;
if(cfd < 0 && (cfd = open(cfn, O_RDWR)) < 0)
goto err;
AUDIO_INITINFO(&info);
info.play.precision = Bits;
info.play.channels = Channels;
info.play.sample_rate = speed;
info.play.encoding = AUDIO_ENCODING_LINEAR;
if(ioctl(afd, AUDIO_SETINFO, &info) < 0)
goto err;
return;
err:
if(afd >= 0)
close(afd);
afd = -1;
if(cfd >= 0)
close(cfd);
cfd = -1;
oserror();
}
void
audiodevclose(void)
{
if(afd >= 0)
close(afd);
if(cfd >= 0)
close(cfd);
afd = -1;
cfd = -1;
}
static double
fromsun(double val, double min, double max)
{
return (val-min) / (max-min);
}
static double
tosun(double val, double min, double max)
{
return val*(max-min) + min;
}
static void
setvolbal(double left, double right)
{
audio_info_t info;
double vol, bal;
if (left < 0 || right < 0) {
/* should not happen */
return;
} else if (left == right) {
vol = tosun(left/100.0, AUDIO_MIN_GAIN, AUDIO_MAX_GAIN);
bal = AUDIO_MID_BALANCE;
} else if (left < right) {
vol = tosun(right/100.0, AUDIO_MIN_GAIN, AUDIO_MAX_GAIN);
bal = tosun(1.0 - left/right, AUDIO_MID_BALANCE, AUDIO_RIGHT_BALANCE);
} else if (right < left) {
vol = tosun(left/100.0, AUDIO_MIN_GAIN, AUDIO_MAX_GAIN);
bal = tosun(1.0 - right/left, AUDIO_MID_BALANCE, AUDIO_LEFT_BALANCE);
}
AUDIO_INITINFO(&info);
info.play.gain = (long)(vol+0.5);
info.play.balance = (long)(bal+0.5);
if(ioctl(cfd, AUDIO_SETINFO, &info) < 0)
oserror();
}
static void
getvolbal(int *left, int *right)
{
audio_info_t info;
double gain, bal, vol, l, r;
AUDIO_INITINFO(&info);
if (ioctl(cfd, AUDIO_GETINFO, &info) < 0)
oserror();
gain = info.play.gain;
bal = info.play.balance;
vol = fromsun(gain, AUDIO_MIN_GAIN, AUDIO_MAX_GAIN) * 100.0;
if (bal == AUDIO_MID_BALANCE) {
l = r = vol;
} else if (bal < AUDIO_MID_BALANCE) {
l = vol;
r = vol * (1.0 - fromsun(bal, AUDIO_MID_BALANCE, AUDIO_LEFT_BALANCE));
} else {
r = vol;
l = vol * (1.0 - fromsun(bal, AUDIO_MID_BALANCE, AUDIO_RIGHT_BALANCE));
}
*left = (long)(l+0.5);
*right = (long)(r+0.5);
return;
}
void
audiodevsetvol(int what, int left, int right)
{
audio_info_t info;
ulong x;
int l, r;
if (afn == nil || cfn == nil)
audiodevinit();
if(cfd < 0 && (cfd = open(cfn, O_RDWR)) < 0) {
cfd = -1;
oserror();
}
if(what == Vspeed){
x = left;
AUDIO_INITINFO(&info);
info.play.sample_rate = x;
if(ioctl(cfd, AUDIO_SETINFO, &info) < 0)
oserror();
speed = x;
return;
}
if(what == Vaudio){
getvolbal(&l, &r);
if (left < 0)
setvolbal(l, right);
else if (right < 0)
setvolbal(left, r);
else
setvolbal(left, right);
return;
}
}
void
audiodevgetvol(int what, int *left, int *right)
{
audio_info_t info;
if (afn == nil || cfn == nil)
audiodevinit();
if(cfd < 0 && (cfd = open(cfn, O_RDWR)) < 0) {
cfd = -1;
oserror();
}
switch(what) {
case Vspeed:
*left = *right = speed;
break;
case Vaudio:
getvolbal(left, right);
break;
case Vtreb:
case Vbass:
*left = *right = 50;
break;
default:
*left = *right = 0;
}
}
static uchar *buf = 0;
static int nbuf = 0;
int
audiodevwrite(void *v, int n)
{
int i, m, tot;
uchar *p;
if (needswap) {
if (nbuf < n) {
buf = (uchar*)erealloc(buf, n);
if(buf == nil)
panic("out of memory");
nbuf = n;
}
p = (uchar*)v;
for(i=0; i+1<n; i+=2) {
buf[i] = p[i+1];
buf[i+1] = p[i];
}
p = buf;
} else
p = (uchar*)v;
for(tot=0; tot<n; tot+=m)
if((m = write(afd, p+tot, n-tot)) <= 0)
oserror();
return tot;
}
int
audiodevread(void *v, int n)
{
error("no reading");
return -1;
}