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games/opl3: fix choking on high tempo streams

also remove bullshit concurrency and locks, what was i thinking

--- a/sys/src/games/opl3/opl3m.c

+++ b/sys/src/games/opl3/opl3m.c

@@ -8,6 +8,8 @@

 enum{

 	OPLrate = 49716,	/* 14318180Hz master clock / 288 */

+	Devrate = 44100,

+	Srate = Devrate / 100,

 };

 void

@@ -22,10 +24,8 @@

 {

 	int rate, stream, n, r, v, fd, pfd[2];

 	uchar sb[64*1024], u[5];

-	double f;

-	vlong dt, T;

+	double s, f, dt, T;

 	Biobuf *bi;

-	QLock slock;

 	fd = 0;

 	stream = 0;

@@ -73,15 +73,13 @@

 			sysfatal("rfork: %r");

 		case 0:

 			for(;;){

-				qlock(&slock);

-				n = OPLrate / 1e3;

-				T += n * (1e9 / OPLrate);

+				n = Srate;

+				s = 1e9 * n / OPLrate;

+				T += s;

+				dt = floor((T - nsec()) / 1e6);

 				n *= 4;

 				opl3out(sb, n);

-				n = write(pfd[1], sb, n);

-				dt = (T - nsec()) / 1e6;

-				qunlock(&slock);

-				if(n <= 0)

+				if(write(pfd[1], sb, n) != n)

 					break;

 				if(dt > 0)

 					sleep(dt);

@@ -92,18 +90,18 @@

 		r = u[1] << 8 | u[0];

 		v = u[2];

 		opl3wr(r, v);

+		if(stream)

+			continue;

 		dt += (u[4] << 8 | u[3]) * f;

-		qlock(&slock);

 		while((n = dt) > 0){

 			if(n > sizeof sb / 4)

 				n = sizeof sb / 4;

 			dt -= n;

-			T += n * (1e9 / OPLrate);

+			T += n * 1e9 / OPLrate;

 			n *= 4;

 			opl3out(sb, n);

 			write(pfd[1], sb, n);

 		}

-		qunlock(&slock);

 	}

 	if(n < 0)

 		sysfatal("read: %r");