From 3cf5031291eaa530d2cb74a29f8fbed084387f25 Mon Sep 17 00:00:00 2001
From: David du Colombier <0intro@gmail.com>
Date: Sat, 28 Mar 1998 00:00:00 +0000
Subject: [PATCH] Plan 9 from Bell Labs 1998-03-28

---
 ip/ip.h    |  1 +
 ip/ipaux.c |  2 +-
 ip/ipmux.c | 60 +++++++++++++++++++++++++++++++-----------------------
 port/qio.c | 30 ++++++++++++++++++---------
 4 files changed, 57 insertions(+), 36 deletions(-)

diff --git a/ip/ip.h b/ip/ip.h
index 950a2d30c95fc92862ac5259150971589422a72a..103c218fd6afd60e650c1a65e7550cc7f0321c47 100644
--- a/ip/ip.h
+++ b/ip/ip.h
@@ -411,6 +411,7 @@ struct Cmdbuf
 extern int	myetheraddr(uchar*, char*);
 extern ulong	parseip(uchar*, char*);
 extern ulong	parseipmask(uchar*, char*);
+extern char*	v4parseip(uchar*, char*);
 extern void	maskip(uchar *from, uchar *mask, uchar *to);
 extern int	parsemac(uchar *to, char *from, int len);
 extern uchar*	defmask(uchar*);
diff --git a/ip/ipaux.c b/ip/ipaux.c
index 7dd0f65fc8a4ee6c80a02f62b5fa35b6f5550847..ce9b66046138eaac60fd136caf9d2a68529671d6 100644
--- a/ip/ipaux.c
+++ b/ip/ipaux.c
@@ -210,7 +210,7 @@ common:
 
 #define CLASS(p) ((*(uchar*)(p))>>6)
 
-static char*
+extern char*
 v4parseip(uchar *to, char *from)
 {
 	int i;
diff --git a/ip/ipmux.c b/ip/ipmux.c
index a44881cc076c5d2112fdd5ce0985f66a0481383e..b3b5d54555f64ae37263fc0d2ec24d883e6441bd 100644
--- a/ip/ipmux.c
+++ b/ip/ipmux.c
@@ -61,7 +61,7 @@ struct Ipmux
 	Ipmux	*no;
 	uchar	type;
 	uchar	len;		/* length in bytes of item to compare */
-	ushort	off;		/* offset of comparison */
+	short	off;		/* offset of comparison */
 	int	n;		/* number of items val points to */
 	uchar	*val;
 	uchar	*mask;
@@ -78,6 +78,8 @@ struct Ipmuxrock
 	Ipmux	*chain;
 };
 
+static int	ipmuxsprint(Ipmux*, int, char*, int);
+
 static char*
 skipwhite(char *p)
 {
@@ -111,25 +113,25 @@ parseop(char **pp)
 	p = skipwhite(p);
 	if(strncmp(p, "dst", 3) == 0){
 		type = Tdst;
-		off = ((ulong)(ipoff->dst)) - IPHDR;
+		off = (ulong)(ipoff->dst);
 		len = IPv4addrlen;
 		p += 3;
 	}
 	else if(strncmp(p, "src", 3) == 0){
 		type = Tsrc;
-		off = ((ulong)(ipoff->src)) - IPHDR;
+		off = (ulong)(ipoff->src);
 		len = IPv4addrlen;
 		p += 3;
 	}
 	else if(strncmp(p, "ifc", 3) == 0){
 		type = Tifc;
-		off = -IPv4addrlen - IPHDR;
+		off = -IPv4addrlen;
 		len = IPv4addrlen;
 		p += 3;
 	}
 	else if(strncmp(p, "proto", 5) == 0){
 		type = Tproto;
-		off = ((ulong)&(ipoff->proto)) - IPHDR;
+		off = (ulong)&(ipoff->proto);
 		len = 1;
 		p += 5;
 	}
@@ -158,7 +160,7 @@ parseop(char **pp)
 			return nil;
 		p++;
 		len = end - off + 1;
-		off += ((ulong)(ipoff->data)) - IPHDR;
+		off += (ulong)(ipoff->data);
 	}
 	else 
 		return nil;
@@ -232,7 +234,7 @@ parsemux(char *p)
 		case Tdst:
 		case Tifc:
 			f->mask = smalloc(f->len);
-			parseipmask(f->mask, mask);
+			v4parseip(f->mask, mask);
 			break;
 		case Tdata:
 			f->mask = smalloc(f->len);
@@ -257,7 +259,7 @@ parsemux(char *p)
 		case Tsrc:
 		case Tdst:
 		case Tifc:
-			parseip(v, vals[n]);
+			v4parseip(v, vals[n]);
 			break;
 		case Tproto:
 		case Tdata:
@@ -538,8 +540,10 @@ ipmuxconnect(Conv *c, char **argv, int argc)
 static int
 ipmuxstate(Conv *c, char *state, int n)
 {
-	USED(c);
-	return snprint(state, n, "%s", "Datagram");
+	Ipmuxrock *r;
+	
+	r = (Ipmuxrock*)(c->ptcl);
+	return ipmuxsprint(r->chain, 0, state, n);
 }
 
 static void
@@ -579,6 +583,7 @@ ipmuxclose(Conv *c)
 	ipmuxremove(&(c->p->priv), r->chain);
 	wunlock(f);
 	ipmuxtreefree(r->chain);
+	r->chain = nil;
 
 	unlock(c);
 }
@@ -612,13 +617,12 @@ ipmuxiput(Proto *p, uchar *ia, Block *bp)
 		goto nomatch;
 
 	/* make interface address part of packet */
-	h = bp->rp - IPHDR - IPv4addrlen;
-	if(h < bp->base){
-		bp = padblock(bp, IPHDR + IPv4addrlen);
-		h = bp->rp;
-		bp->rp += IPHDR + IPv4addrlen;
+	if(bp->rp - bp->base < IPv4addrlen){
+		bp = padblock(bp, IPv4addrlen);
+		bp->rp += IPv4addrlen;
 	}
-	memmove(h, ia+IPv4off, IPv4addrlen);
+	h = bp->rp;
+	memmove(h-IPv4addrlen, ia+IPv4off, IPv4addrlen);
 	len = BLEN(bp);
 
 	/* run the v4 filter (needs optimizing) */
@@ -635,29 +639,29 @@ ipmuxiput(Proto *p, uchar *ia, Block *bp)
 			m = mux->mask;
 			hp = h + mux->off;
 			for(ve = v + mux->len; v < ve; v++){
-				if((*hp++ & *m++) != *v++)
+				if((*hp++ & *m++) != *v)
 					break;
 			}
 			if(v == ve){
 				if(mux->conv != nil)
 					c = mux->conv;
 				mux = mux->yes;
-				break;
+				goto match;
 			}
 		}
-		if(v == e)
-			mux = mux->no;
+		mux = mux->no;
+match:;
 	}
 	runlock(f);
 
 	if(c != nil){
-		bp->rp -= IPHDR;
 		if(bp->next){
 			bp = concatblock(bp);
 			if(bp == 0)
 				panic("ilpullup");
 		}
 		qpass(c->rq, bp);
+		return;
 	}
 
 nomatch:
@@ -675,20 +679,26 @@ static int
 ipmuxsprint(Ipmux *mux, int level, char *buf, int len)
 {
 	int i, j, n;
+	uchar *v;
 
 	n = 0;
-	if(mux == nil)
-		return n;
 	for(i = 0; i < level; i++)
 		n += snprint(buf+n, len-n, " ");
-	n += snprint(buf+n, len-n, "h[%d:%d] & ", mux->off, mux->off+mux->len-1);
+	if(mux == nil){
+		n += snprint(buf+n, len-n, "\n");
+		return n;
+	}
+	n += snprint(buf+n, len-n, "h[%d:%d]&", mux->off, mux->off+mux->len-1);
 	for(i = 0; i < mux->len; i++)
 		n += snprint(buf+n, len - n, "%2.2ux", mux->mask[i]);
+	n += snprint(buf+n, len-n, "=");
+	v = mux->val;
 	for(j = 0; j < mux->n; j++){
 		for(i = 0; i < mux->len; i++)
-			n += snprint(buf+n, len - n, "%2.2ux", mux->mask[i]);
+			n += snprint(buf+n, len - n, "%2.2ux", *v++);
 		n += snprint(buf+n, len-n, "|");
 	}
+	n += snprint(buf+n, len-n, "\n");
 	level++;
 	n += ipmuxsprint(mux->no, level, buf+n, len-n);
 	n += ipmuxsprint(mux->yes, level, buf+n, len-n);
diff --git a/port/qio.c b/port/qio.c
index 7d1ad976785792aabd0f51336b62c9fe5a9b26e2..96774f2d1c89bfe1199aa409e432936d1ad55176 100644
--- a/port/qio.c
+++ b/port/qio.c
@@ -766,12 +766,14 @@ qopen(int limit, int msg, void (*kick)(void*), void *arg)
 	if(q == 0)
 		return 0;
 
+	ilock(q);
 	q->limit = q->inilim = limit;
 	q->kick = kick;
 	q->arg = arg;
 	q->state = msg ? Qmsg : 0;
 	q->state |= Qstarve;
 	q->eof = 0;
+	iunlock(q);
 
 	return q;
 }
@@ -911,30 +913,36 @@ qbwrite(Queue *q, Block *b)
 	dowakeup = 0;
 	n = BLEN(b);
 
+	qlock(&q->wlock);
 	if(waserror()){
 		qunlock(&q->wlock);
 		nexterror();
 	}
-	qlock(&q->wlock);
 
 	/* flow control */
-	while(!qnotfull(q)){
+	for(;;){
+		ilock(q);
+
+		if(q->state & Qclosed){
+			iunlock(q);
+			freeb(b);
+			error(q->err);
+		}
+
+		if(q->len < q->limit)
+			break;
+
 		if(q->noblock){
+			iunlock(q);
 			freeb(b);
 			qunlock(&q->wlock);
 			poperror();
 			return n;
 		}
-		q->state |= Qflow;
-		sleep(&q->wr, qnotfull, q);
-	}
-
-	ilock(q);
 
-	if(q->state & Qclosed){
+		q->state |= Qflow;
 		iunlock(q);
-		freeb(b);
-		error(q->err);
+		sleep(&q->wr, qnotfull, q);
 	}
 
 	if(q->bfirst)
@@ -1120,10 +1128,12 @@ qhangup(Queue *q, char *msg)
 void
 qreopen(Queue *q)
 {
+	ilock(q);
 	q->state &= ~Qclosed;
 	q->state |= Qstarve;
 	q->eof = 0;
 	q->limit = q->inilim;
+	iunlock(q);
 }
 
 /*