Terminate mixer description dump with a MIXSYNC message. Fix

server-side "desc" temporary buffer size.

libsndio/amsg.h

@@ -57,6 +57,7 @@ struct amsg {
 #define AMSG_AUTH	12	/* send authentication cookie */
 #define AMSG_MIXSUB	13	/* ondesc/onctl subscription */
 #define AMSG_MIXSET	14	/* set mixer control value */
+#define AMSG_MIXSYNC	15	/* end of mixer description */
 	uint32_t cmd;
 	uint32_t __pad;
 	union {

libsndio/siomix_aucat.c

@@ -96,7 +96,6 @@ siomix_aucat_rdata(struct siomix_aucat_hdl *hdl)
 		}
 		hdl->buf_wpos = 0;
 	}
-	hdl->dump_wait = 0;
 	return 1;
 }
 
@@ -120,6 +119,11 @@ siomix_aucat_runmsg(struct siomix_aucat_hdl *hdl)
 		    ntohs(hdl->aucat.rmsg.u.mixset.addr),
 		    ntohs(hdl->aucat.rmsg.u.mixset.val));
 		break;
+	case AMSG_MIXSYNC:
+		DPRINTF("siomix_aucat_runmsg: got MIXSYNC\n");
+		hdl->dump_wait = 0;
+		_siomix_ondesc_cb(&hdl->siomix, NULL, 0);
+		break;
 	default:
 		DPRINTF("sio_aucat_runmsg: unhandled message %u\n",
 		    hdl->aucat.rmsg.cmd);

sndiod/sock.c

@@ -33,6 +33,8 @@
 #include "utils.h"
 #include "bsd-compat.h"
 
+#define SOCK_CTLDESC_SIZE	3	/* number of entries in s->ctldesc */
+
 void sock_log(struct sock *);
 void sock_close(struct sock *);
 void sock_slot_fill(void *);
@@ -874,7 +876,7 @@ sock_hello(struct sock *f)
 			}
 			return 0;
 		}
-		f->ctldesc = xmalloc(dev_nctl(f->ctlslot->dev) *
+		f->ctldesc = xmalloc(SOCK_CTLDESC_SIZE *
 		    sizeof(struct amsg_mix_desc));
 		f->ctlops = 0;
 		return 1;
@@ -1272,6 +1274,7 @@ sock_execmsg(struct sock *f)
 				}
 			}
 			f->ctlops |= SOCK_CTLDESC;
+			f->ctlsyncpending = 1;
 		} else
 			f->ctlops &= ~SOCK_CTLDESC;
 		if (m->u.mixsub.val) {
@@ -1543,12 +1546,22 @@ sock_buildmsg(struct sock *f)
 		return 1;
 	}
 
+	/*
+	 * XXX: add a flag indicating if there are changes
+	 * in controls not seen by this client, rather
+	 * than walking through the full list of control
+	 * searching for the {desc,val}_mask bits
+	 */
 	if (f->ctlslot && (f->ctlops & SOCK_CTLDESC)) {
 		desc = f->ctldesc;
 		mask = f->ctlslot->mask;
+		size = 0;
 		for (c = f->ctlslot->dev->ctl_list; c != NULL; c = c->next) {
 			if ((c->desc_mask & mask) == 0)
 				continue;
+			if (size == SOCK_CTLDESC_SIZE *
+				sizeof(struct amsg_mix_desc))
+				break;
 			c->desc_mask &= ~mask;
 			c->val_mask &= ~mask;
 			strlcpy(desc->chan0.str, c->chan0.str,
@@ -1561,10 +1574,10 @@ sock_buildmsg(struct sock *f)
 			strlcpy(desc->func, c->func, AMSG_MIX_NAMEMAX);
 			desc->addr = htons(c->addr);
 			desc->curval = htons(c->curval);
+			size += sizeof(struct amsg_mix_desc);
 			desc++;
 		}
-		if (desc != f->ctldesc) {
-			size = (char *)desc - (char *)f->ctldesc;
+		if (size > 0) {
 			AMSG_INIT(&f->wmsg);
 			f->wmsg.cmd = htonl(AMSG_DATA);
 			f->wmsg.u.data.size = htonl(size);
@@ -1600,6 +1613,19 @@ sock_buildmsg(struct sock *f)
 			return 1;
 		}
 	}
+	if (f->ctlslot && f->ctlsyncpending) {
+		f->ctlsyncpending = 0;
+		f->wmsg.cmd = htonl(AMSG_MIXSYNC);
+		f->wtodo = sizeof(struct amsg);
+		f->wstate = SOCK_WMSG;
+#ifdef DEBUG
+		if (log_level >= 3) {
+			sock_log(f);
+			log_puts(": building mixer MIXSYNC message\n");
+		}
+#endif
+		return 1;
+	}
 #ifdef DEBUG
 	if (log_level >= 4) {
 		sock_log(f);

sndiod/sock.h

@@ -50,7 +50,7 @@ struct sock {
 #define SOCK_START	3		/* filling play buffers */
 #define SOCK_STOP	4		/* draining rec buffers */
 	unsigned int pstate;		/* one of the above */
-	int tickpending;		/* tick waiting to be transmitted */	
+	int tickpending;		/* tick waiting to be transmitted */
 	int fillpending;		/* flowctl waiting to be transmitted */
 	int stoppending;		/* last STOP ack to be sent */
 	unsigned int walign;		/* align written data to this */
@@ -61,10 +61,11 @@ struct sock {
 	struct midi *midi;		/* midi endpoint */
 	struct port *port;		/* midi port */
 	struct ctlslot *ctlslot;
-	struct amsg_mix_desc *ctldesc;
+	struct amsg_mix_desc *ctldesc;	/* temporary buffer */
 #define SOCK_CTLDESC	1		/* dump desc and send changes */
 #define SOCK_CTLVAL	2		/* send value changes */
-	unsigned int ctlops;
+	unsigned int ctlops;		/* bitmap of above */
+	int ctlsyncpending;		/* mixsync waiting to be transmitted */
 };
 
 struct sock *sock_new(int fd);