shithub: jacksense

ref: b8559f471b8904b3033ca397e9582ae74da7056f
dir: /jacksense.c/

#include <u.h>
#include <libc.h>
#include <bio.h>

static void
usage(void)
{
	fprint(2, "usage: %s [-h hp_safe_volume] [-s sp_safe_volume]\n", argv0);
	exits("usage");
}

void
main(int argc, char **argv)
{
	int hp, sp, cmd, ctl, vol, lastvol, newvol;
	int hpsafevol, spsafevol;
	u32int x, y[4], has, had;
	Biobuf *b;
	char *s, *a[16], tmp[32];

	hpsafevol = 65;
	spsafevol = 70;
	ARGBEGIN{
	case 'h':
		hpsafevol = atoi(EARGF(usage()));
		break;
	case 's':
		spsafevol = atoi(EARGF(usage()));
		break;
	default:
		usage();
	}ARGEND

	if((cmd = open("/dev/hdacmd", ORDWR)) < 0)
		sysfatal("%r");
	if((ctl = open("/dev/audioctl", OWRITE)) < 0)
		sysfatal("%r");
	if((vol = open("/dev/volume", ORDWR)) < 0)
		sysfatal("%r");
	if((b = Bopen("/dev/audiostat", OREAD)) == nil)
		sysfatal("%r");
	sp = -1;
	hp = -1;
	while((sp < 0 || hp < 0) && (s = Brdline(b, '\n')) != nil){
		s[Blinelen(b)-1] = 0;
		if(tokenize(s, a, nelem(a)) < 8)
			continue;
		if(strcmp(a[0], "pin") != 0 || strcmp(a[2], "out") != 0)
			continue;
		if(strcmp(a[3], "jack") == 0 && strcmp(a[6], "hpout") == 0)
			hp = atoi(a[1]);
		if(strcmp(a[3], "fix") == 0 && strcmp(a[6], "speaker") == 0)
			sp = atoi(a[1]);
	}
	if(sp < 0 || hp < 0){
		fprint(2, "couldn't detect pins\n");
		exits("pins");
	}

	x = 0x0f0900 | (hp<<4)<<16 | (hp>>4)<<24;
	had = -1;
	lastvol = (spsafevol < hpsafevol ? spsafevol : hpsafevol)*2/3;
	for(;;){
		if(write(cmd, &x, 4) != 4 || read(cmd, y, sizeof(y)) < 4)
			sysfatal("failed");
		has = y[0] & (1<<31);
		if(has != had){
			newvol = lastvol;
			if(pread(vol, tmp, sizeof(tmp)-1, 0) > 0 && strncmp(tmp, "master ", 7) == 0)
				lastvol = atoi(tmp+7);
			if(had == ~0)
				newvol = lastvol;

			/* SAVE MY EARS, OK? THANKS */
			if(has && newvol > hpsafevol)
				newvol = hpsafevol;
			else if(!has && newvol > spsafevol)
				newvol = spsafevol;

			fprint(ctl, "pin %d\n", has ? hp : sp);
			fprint(vol, "%d\n", newvol);
		}
		had = has;
		sleep(300);
	}
}