add a writable ``appbufsz'' field to the sa_par structure, containing

the program-part of the buffer size, ie the part that is subject to
underruns. Useful for apps like cdio(1) that don't have their own
rings, or to apps that have a minimum ring size constraint. Setting
the ``bufsz'' parameter becomes deprecated.
ok jakemsr

12 files changed, 107 insertions, 78 deletions

diff --git a/lib/libsndio/aucat.c b/lib/libsndio/aucat.c
index d3add816a06..2f373c8815f 100644
--- a/lib/libsndio/aucat.c
+++ b/lib/libsndio/aucat.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: aucat.c,v 1.4 2008/11/17 07:04:13 ratchov Exp $	*/
+/*	$OpenBSD: aucat.c,v 1.5 2008/12/17 07:19:27 ratchov Exp $	*/
 /*
  * Copyright (c) 2008 Alexandre Ratchov <alex@caoua.org>
  *
@@ -326,7 +326,7 @@ aucat_setpar(struct sio_hdl *sh, struct sio_par *par)
 	hdl->wmsg.u.par.le = par->le;
 	hdl->wmsg.u.par.msb = par->msb;
 	hdl->wmsg.u.par.rate = par->rate;
-	hdl->wmsg.u.par.bufsz = par->bufsz;
+	hdl->wmsg.u.par.appbufsz = par->appbufsz;
 	hdl->wmsg.u.par.xrun = par->xrun;
 	hdl->wmsg.u.par.mode = hdl->sa.mode;
 	if (hdl->sa.mode & SIO_REC)
@@ -364,6 +364,7 @@ aucat_getpar(struct sio_hdl *sh, struct sio_par *par)
 	par->msb = hdl->rmsg.u.par.msb;
 	par->rate = hdl->rmsg.u.par.rate;
 	par->bufsz = hdl->rmsg.u.par.bufsz;
+	par->appbufsz = hdl->rmsg.u.par.appbufsz;
 	par->xrun = hdl->rmsg.u.par.xrun;
 	par->round = hdl->rmsg.u.par.round;
 	if (hdl->sa.mode & SIO_PLAY)
diff --git a/lib/libsndio/shlib_version b/lib/libsndio/shlib_version
index 3f0196ebf4a..83a67c373cc 100644
--- a/lib/libsndio/shlib_version
+++ b/lib/libsndio/shlib_version
@@ -1,2 +1,2 @@
 major=3
-minor=1
+minor=2
diff --git a/lib/libsndio/sio_open.3 b/lib/libsndio/sio_open.3
index c194efa58d6..df0c0edf603 100644
--- a/lib/libsndio/sio_open.3
+++ b/lib/libsndio/sio_open.3
@@ -1,4 +1,4 @@
-.\" $OpenBSD: sio_open.3,v 1.8 2008/11/17 07:49:48 jmc Exp $
+.\" $OpenBSD: sio_open.3,v 1.9 2008/12/17 07:19:27 ratchov Exp $
 .\"
 .\" Copyright (c) 2007 Alexandre Ratchov <alex@caoua.org>
 .\"
@@ -14,7 +14,7 @@
 .\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 .\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 .\"
-.Dd $Mdocdate: November 17 2008 $
+.Dd $Mdocdate: December 17 2008 $
 .Dt SIO_OPEN 3
 .Os
 .Sh NAME
@@ -149,27 +149,28 @@ handle.
 Audio streams always use linear interleaved encoding.
 The set of parameters of the stream that can be controlled
 is given by the following structure:
-.Bd -literal -offset -indent
+.Bd -literal
 struct sio_par {
-	unsigned bits;	/* bits per sample */
-	unsigned bps;	/* bytes per sample */
-	unsigned sig;	/* 1 = signed, 0 = unsigned */
-	unsigned le;	/* 1 = LE, 0 = BE byte order */
-	unsigned msb;	/* 1 = MSB, 0 = LSB aligned */
-	unsigned rchan;	/* number channels for recording */
-	unsigned pchan;	/* number channels for playback */
-	unsigned rate;	/* frames per second */
-	unsigned bufsz;	/* frames in the stream buffer */
-	unsigned round;	/* optimal buffer size divisor */
+	unsigned bits;		/* bits per sample */
+	unsigned bps;		/* bytes per sample */
+	unsigned sig;		/* 1 = signed, 0 = unsigned */
+	unsigned le;		/* 1 = LE, 0 = BE byte order */
+	unsigned msb;		/* 1 = MSB, 0 = LSB aligned */
+	unsigned rchan;		/* number channels for recording */
+	unsigned pchan;		/* number channels for playback */
+	unsigned rate;		/* frames per second */
+	unsigned appbufsz;	/* minimum buffer size without xruns */
+	unsigned bufsz;		/* end-to-end buffer size (read-only) */
+	unsigned round;		/* optimal buffer size divisor */
 #define SIO_IGNORE	0	/* pause during xrun */
-#define SIO_SYNC		1	/* resync after xrun */
+#define SIO_SYNC	1	/* resync after xrun */
 #define SIO_ERROR	2	/* terminate on xrun */
-	unsigned xrun;	/* what to do on overrun/underrun */
+	unsigned xrun;		/* what to do on overrun/underrun */
 };
 .Ed
 .Pp
 The parameters are as follows:
-.Bl -tag -width "round"
+.Bl -tag -width "appbufsz"
 .It Va bits
 Number of bits per sample: must be between 1 and 32.
 .It Va bps
@@ -202,8 +203,19 @@ mode was selected.
 .It Va rate
 The sampling frequency in Hz.
 .It Va bufsz
-The number of frames that will be buffered for both
-play and record directions.
+The maximum number of frames that may be buffered.
+This parameter takes into accout any buffers, and
+can be used for latency calculations.
+This parameter is read-only.
+.It Va appbufsz
+Size of the buffer in frames the application must maintain non empty
+(on the play end) or non full (on the record end) by calling
+.Fn sio_write
+or
+.Fn sio_read
+fast enough to avoid overrun or underrun conditions.
+The audio subsystem may use additionnal buffering, thus this
+parameter cannot be used for latency calculations
 .It Va round
 Optimal number of frames that the application buffers
 should be a multiple of, to get best performance.
@@ -578,7 +590,7 @@ for this.
 .Ss Handling buffer overruns and underruns
 When the application cannot accept recorded data fast enough,
 the record buffer (of size
-.Va bufsz )
+.Va appbufsz )
 might overrun; in this case recorded data is lost.
 Similarly if the application cannot provide data to play
 fast enough, the play buffer underruns and silence is played
diff --git a/lib/libsndio/sndio.c b/lib/libsndio/sndio.c
index cccc38905ee..a849f4bf7d0 100644
--- a/lib/libsndio/sndio.c
+++ b/lib/libsndio/sndio.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: sndio.c,v 1.7 2008/11/20 16:31:26 ratchov Exp $	*/
+/*	$OpenBSD: sndio.c,v 1.8 2008/12/17 07:19:27 ratchov Exp $	*/
 /*
  * Copyright (c) 2008 Alexandre Ratchov <alex@caoua.org>
  *
@@ -266,8 +266,12 @@ sio_setpar(struct sio_hdl *hdl, struct sio_par *par)
 		hdl->eof = 1;
 		return 0;
 	}
-	if (par->rate != (unsigned)~0 && par->bufsz == (unsigned)~0)
-		par->bufsz = par->rate * 200 / 1000;
+	if (par->bufsz != (unsigned)~0) {
+		fprintf(stderr, "sio_setpar: setting bufsz is deprecated\n");
+		par->appbufsz = par->bufsz;
+	}
+	if (par->rate != (unsigned)~0 && par->appbufsz == (unsigned)~0)
+		par->appbufsz = par->rate * 200 / 1000;
 	return hdl->ops->setpar(hdl, par);
 }
 
diff --git a/lib/libsndio/sndio.h b/lib/libsndio/sndio.h
index ec0afaa468d..1b3dddbb4b6 100644
--- a/lib/libsndio/sndio.h
+++ b/lib/libsndio/sndio.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: sndio.h,v 1.3 2008/11/11 19:39:35 ratchov Exp $	*/
+/*	$OpenBSD: sndio.h,v 1.4 2008/12/17 07:19:27 ratchov Exp $	*/
 /*
  * Copyright (c) 2008 Alexandre Ratchov <alex@caoua.org>
  *
@@ -28,29 +28,30 @@ struct sio_hdl;
  * parameters of a full-duplex stream
  */
 struct sio_par {
-	unsigned bits;	/* bits per sample */
-	unsigned bps;	/* bytes per sample */
-	unsigned sig;	/* 1 = signed, 0 = unsigned */
-	unsigned le;	/* 1 = LE, 0 = BE byte order */
-	unsigned msb;	/* 1 = MSB, 0 = LSB aligned */
-	unsigned rchan;	/* number channels for recording direction */
-	unsigned pchan;	/* number channels for playback direction */
-	unsigned rate;	/* frames per second */
-	unsigned bufsz;	/* minimum buffer size */
+	unsigned bits;		/* bits per sample */
+	unsigned bps;		/* bytes per sample */
+	unsigned sig;		/* 1 = signed, 0 = unsigned */
+	unsigned le;		/* 1 = LE, 0 = BE byte order */
+	unsigned msb;		/* 1 = MSB, 0 = LSB aligned */
+	unsigned rchan;		/* number channels for recording direction */
+	unsigned pchan;		/* number channels for playback direction */
+	unsigned rate;		/* frames per second */
+	unsigned bufsz;		/* end-to-end buffer size */
 #define SIO_IGNORE	0	/* pause during xrun */
-#define SIO_SYNC		1	/* resync after xrun */
+#define SIO_SYNC	1	/* resync after xrun */
 #define SIO_ERROR	2	/* terminate on xrun */
-	unsigned xrun;	/* what to do on overruns/underruns */
-	unsigned round;	/* optimal bufsz divisor */
-	int __pad[4];	/* for future use */
-	int __magic;	/* for internal/debug purposes only */
+	unsigned xrun;		/* what to do on overruns/underruns */
+	unsigned round;		/* optimal bufsz divisor */
+	unsigned appbufsz;	/* minimum buffer size */
+	int __pad[3];		/* for future use */
+	int __magic;		/* for internal/debug purposes only */
 };
 
 /*
  * capabilities of a stream
  */
 struct sio_cap {
-#define SIO_NENC		8
+#define SIO_NENC	8
 #define SIO_NCHAN	8
 #define SIO_NRATE	16
 #define SIO_NCONF	4
@@ -79,8 +80,8 @@ struct sio_cap {
 /*
  * mode bitmap
  */
-#define SIO_PLAY 1
-#define SIO_REC	2
+#define SIO_PLAY	1
+#define SIO_REC		2
 
 /*
  * maximum size of the encording string (the longest possible
diff --git a/lib/libsndio/sun.c b/lib/libsndio/sun.c
index 5b4db13842b..14dbbe14400 100644
--- a/lib/libsndio/sun.c
+++ b/lib/libsndio/sun.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: sun.c,v 1.7 2008/11/20 16:31:26 ratchov Exp $	*/
+/*	$OpenBSD: sun.c,v 1.8 2008/12/17 07:19:27 ratchov Exp $	*/
 /*
  * Copyright (c) 2008 Alexandre Ratchov <alex@caoua.org>
  *
@@ -494,7 +494,7 @@ sio_open_sun(char *path, unsigned mode, int nbio)
 	par.rate = 48000;
 	par.sig = 1;
 	par.bits = 16;
-	par.bufsz = 1200;
+	par.appbufsz = 1200;
 	if (!sio_setpar(&hdl->sa, &par))
 		goto bad_close;
 	return (struct sio_hdl *)hdl;
@@ -639,7 +639,7 @@ sun_setpar(struct sio_hdl *sh, struct sio_par *par)
 	 * if block size and buffer size are not both set then
 	 * set the blocksize to half the buffer size
 	 */ 
-	bufsz = par->bufsz;
+	bufsz = par->appbufsz;
 	round = par->round;
 	if (bufsz != (unsigned)~0) {
 		if (round == (unsigned)~0)
@@ -751,7 +751,8 @@ sun_getpar(struct sio_hdl *sh, struct sio_par *par)
 	par->round = (hdl->sa.mode & SIO_REC) ?
 	    aui.record.block_size / (par->bps * par->rchan) :
 	    aui.play.block_size / (par->bps * par->pchan);
-	par->bufsz = aui.hiwat * par->round;
+	par->appbufsz = aui.hiwat * par->round;
+	par->bufsz = par->appbufsz;
 	return 1;
 }
 
diff --git a/regress/lib/libsndio/fd/fd.c b/regress/lib/libsndio/fd/fd.c
index 9a76946bc55..d25f32acdc2 100644
--- a/regress/lib/libsndio/fd/fd.c
+++ b/regress/lib/libsndio/fd/fd.c
@@ -228,7 +228,7 @@ main(int argc, char **argv) {
 			playpath = optarg;
 			break;
 		case 'b':
-			if (sscanf(optarg, "%u", &par.bufsz) != 1) {
+			if (sscanf(optarg, "%u", &par.appbufsz) != 1) {
 				fprintf(stderr, "%s: bad buf size\n", optarg);
 				exit(1);
 			}
diff --git a/regress/lib/libsndio/play/play.c b/regress/lib/libsndio/play/play.c
index a3b28b42ba3..6d85508da42 100644
--- a/regress/lib/libsndio/play/play.c
+++ b/regress/lib/libsndio/play/play.c
@@ -69,7 +69,7 @@ main(int argc, char **argv) {
 			}
 			break;
 		case 'b':
-			if (sscanf(optarg, "%u", &par.bufsz) != 1) {
+			if (sscanf(optarg, "%u", &par.appbufsz) != 1) {
 				fprintf(stderr, "%s: bad buf size\n", optarg);
 				exit(1);
 			}
diff --git a/regress/lib/libsndio/rec/rec.c b/regress/lib/libsndio/rec/rec.c
index e7d737e8d37..f5c908077dc 100644
--- a/regress/lib/libsndio/rec/rec.c
+++ b/regress/lib/libsndio/rec/rec.c
@@ -44,7 +44,6 @@ main(int argc, char **argv) {
 	par.bits = 16;
 	par.rchan = 2;
 	par.rate = 44100;
-	par.bufsz = 0x10000;
 
 	while ((ch = getopt(argc, argv, "r:c:e:b:x:")) != -1) {
 		switch(ch) {
diff --git a/usr.bin/aucat/amsg.h b/usr.bin/aucat/amsg.h
index 56116c9ee2e..ee8da901165 100644
--- a/usr.bin/aucat/amsg.h
+++ b/usr.bin/aucat/amsg.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: amsg.h,v 1.2 2008/11/11 19:21:20 ratchov Exp $	*/
+/*	$OpenBSD: amsg.h,v 1.3 2008/12/17 07:19:27 ratchov Exp $	*/
 /*
  * Copyright (c) 2008 Alexandre Ratchov <alex@caoua.org>
  *
@@ -55,13 +55,14 @@ struct amsg {
 			uint16_t pchan;		/* play channels */
 			uint16_t rchan;		/* record channels */
 			uint32_t rate;		/* frames per second */
-			uint32_t bufsz;		/* buffered frames */
+			uint32_t bufsz;		/* total buffered frames */
 			uint32_t round;
-			uint32_t _reserved[2];	/* for future use */
+			uint32_t appbufsz;	/* client side bufsz */
+			uint32_t _reserved[1];	/* for future use */
 		} par;
 		struct amsg_cap {
 			uint32_t rate;		/* native rate */
-			uint32_t rate_div;	/* divisor of emul. rates */
+			uint32_t _reserved2[1];	/* for future use */
 			uint16_t rchan;		/* native rec channels */
 			uint16_t pchan;		/* native play channels */
 			uint8_t bits;		/* native bits per sample */
diff --git a/usr.bin/aucat/safile.c b/usr.bin/aucat/safile.c
index 775d451a6aa..f4987e7e29d 100644
--- a/usr.bin/aucat/safile.c
+++ b/usr.bin/aucat/safile.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: safile.c,v 1.5 2008/12/07 17:10:41 ratchov Exp $	*/
+/*	$OpenBSD: safile.c,v 1.6 2008/12/17 07:19:27 ratchov Exp $	*/
 /*
  * Copyright (c) 2008 Alexandre Ratchov <alex@caoua.org>
  *
@@ -125,7 +125,7 @@ safile_new(struct fileops *ops, char *path,
 	}
 	if (opar)
 		par.pchan = opar->cmax - opar->cmin + 1;
-	par.bufsz = *bufsz;
+	par.appbufsz = *bufsz;
 	par.round = *round;
 	if (!sio_setpar(hdl, &par))
 		return 0;
diff --git a/usr.bin/aucat/sock.c b/usr.bin/aucat/sock.c
index a924bc89e01..8b86f31ce5a 100644
--- a/usr.bin/aucat/sock.c
+++ b/usr.bin/aucat/sock.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: sock.c,v 1.9 2008/12/07 17:10:41 ratchov Exp $	*/
+/*	$OpenBSD: sock.c,v 1.10 2008/12/17 07:19:27 ratchov Exp $	*/
 /*
  * Copyright (c) 2008 Alexandre Ratchov <alex@caoua.org>
  *
@@ -280,7 +280,7 @@ sock_new(struct fileops *ops, int fd, char *name,
 		f->mode |= AMSG_PLAY;
 	}
 	f->xrun = AMSG_IGNORE;
-	f->bufsz = 2 * dev_bufsz;
+	f->bufsz = dev_bufsz;
 	f->round = dev_round;
 	f->odelta = f->idelta = 0;
 	f->maxweight = maxweight;
@@ -325,23 +325,19 @@ void
 sock_allocbuf(struct sock *f)
 {
 	struct abuf *rbuf = NULL, *wbuf = NULL;
-	unsigned nfr = 0;
 
 	if (f->mode & AMSG_PLAY) {
-		nfr = f->bufsz - dev_bufsz * f->rpar.rate / dev_rate;
-		rbuf = abuf_new(nfr, &f->rpar);
+		rbuf = abuf_new(f->bufsz, &f->rpar);
 		aproc_setout(f->pipe.file.rproc, rbuf);
 		f->odelta = 0;
 	}
 	if (f->mode & AMSG_REC) {
-		nfr = f->bufsz - dev_bufsz * f->wpar.rate / dev_rate;
-		wbuf = abuf_new(nfr, &f->wpar);
+		wbuf = abuf_new(f->bufsz, &f->wpar);
 		aproc_setin(f->pipe.file.wproc, wbuf);
 		f->idelta = 0;
 	}
 
-	DPRINTF("sock_allocbuf: %p, using %u/%u frames buffer\n",
-	    f, nfr, f->bufsz);
+	DPRINTF("sock_allocbuf: %p, using %u frames buffer\n", f, f->bufsz);
 
 	f->pstate = SOCK_START;
 	if (!(f->mode & AMSG_PLAY))
@@ -634,8 +630,10 @@ sock_setpar(struct sock *f)
 			p->rate = RATE_MAX;
 		f->round = dev_roundof(p->rate);
 		f->rpar.rate = f->wpar.rate = p->rate;
-		if (!AMSG_ISSET(p->bufsz))
-			p->bufsz = 2 * dev_bufsz / dev_round * f->round;
+		if (!AMSG_ISSET(p->appbufsz)) {
+			p->appbufsz = dev_bufsz / dev_round * f->round;
+			DPRINTF("sock_setpar: appbufsz -> %u\n", p->appbufsz);
+		}
 		DPRINTF("sock_setpar: rate -> %u, round -> %u\n",
 		    p->rate, f->round);
 	}
@@ -650,18 +648,29 @@ sock_setpar(struct sock *f)
 		DPRINTF("sock_setpar: xrun -> %u\n", f->xrun);
 	}
 	if (AMSG_ISSET(p->bufsz)) {
+		/*
+		 * XXX: bufsz will become read-only, but for now
+		 *      allow old library to properly work
+		 */
+		DPRINTF("sock_setpar: bufsz: %u\n", p->bufsz);
+		min = (dev_bufsz / dev_round) * f->round;
+		if (p->bufsz < min)
+			p->bufsz = min;
+		p->appbufsz = p->bufsz - min;
+	}
+	if (AMSG_ISSET(p->appbufsz)) {
 		rate = (f->mode & AMSG_PLAY) ? f->rpar.rate : f->wpar.rate;
-		min = (3 * (dev_bufsz / dev_round) + 1) / 2;
-		max = (dev_bufsz + rate + dev_round - 1) / dev_round;
+		min = 1;
+		max = 1 + rate / dev_round;
 		min *= f->round;
 		max *= f->round;
-		p->bufsz += f->round - 1;
-		p->bufsz -= p->bufsz % f->round;
-		if (p->bufsz < min)
-			p->bufsz = min;
-		if (p->bufsz > max)
-			p->bufsz = max;
-		f->bufsz = p->bufsz;
+		p->appbufsz += f->round - 1;
+		p->appbufsz -= p->appbufsz % f->round;
+		if (p->appbufsz < min)
+			p->appbufsz = min;
+		if (p->appbufsz > max)
+			p->appbufsz = max;
+		f->bufsz = p->appbufsz;
 		DPRINTF("sock_setpar: bufsz -> %u\n", f->bufsz);
 	}
 #ifdef DEBUG
@@ -764,7 +773,9 @@ sock_execmsg(struct sock *f)
 		m->u.par.rate = f->rpar.rate;
 		m->u.par.rchan = f->wpar.cmax - f->wpar.cmin + 1;
 		m->u.par.pchan = f->rpar.cmax - f->rpar.cmin + 1;
-		m->u.par.bufsz = f->bufsz;
+		m->u.par.appbufsz = f->bufsz;
+		m->u.par.bufsz = 
+		    f->bufsz + (dev_bufsz / dev_round) * f->round;
 		m->u.par.round = f->round;
 		f->rstate = SOCK_RRET;
 		f->rtodo = sizeof(struct amsg);
@@ -779,7 +790,6 @@ sock_execmsg(struct sock *f)
 		AMSG_INIT(m);
 		m->cmd = AMSG_GETCAP;
 		m->u.cap.rate = dev_rate;
-		m->u.cap.rate_div = dev_rate;
 		m->u.cap.pchan = dev_mix ?
 		    (f->templ_rpar.cmax - f->templ_rpar.cmin + 1) : 0;
 		m->u.cap.rchan = dev_sub ?