fix listen on /net.alt

Reference: /n/atom/patch/applied2013/xlistennetalt
Date: Sun Nov 17 04:06:44 CET 2013
Signed-off-by: quanstro@quanstro.net

--- /sys/src/cmd/aux/xlisten.c	Sun Nov 17 04:06:39 2013
+++ /sys/src/cmd/aux/xlisten.c	Sun Nov 17 04:06:40 2013
@@ -59,7 +59,8 @@
 	uvlong	length;
 
 	Ldir	*largs;
-	char	*ds;		/* dial string */
+	char	*es;		/* exec string */
+	char	*ds;		/* dial string (dial string plus netdir) */
 	char	*proto;
 
 	int	mark;
@@ -253,11 +254,11 @@
 	for(fd = 3; fd < 20; fd++)
 		close(fd);
 	if(Breakexec)
-		snprint(path, sizeof path, "x%s/%s", l->largs->srv, l->ds);	/* broken on purpose */
+		snprint(path, sizeof path, "x%s/%s", l->largs->srv, l->es);	/* broken on purpose */
 	else
-		snprint(path, sizeof path, "%s/%s", l->largs->srv, l->ds);
-	procexecl(l->pidchan, path, l->ds, l->largs->srv, l->proto, i->cdir, nil);
-	llog("%s: exec fails: %r", l->ds);
+		snprint(path, sizeof path, "%s/%s", l->largs->srv, l->es);
+	procexecl(l->pidchan, path, l->es, l->largs->srv, l->proto, i->cdir, nil);
+	llog("%s: exec fails: %r", path);
 
 	/* we can't reject this because we closed the channel already */
 	threadexits("exec: %r");
@@ -276,7 +277,7 @@
 	i = recvp(l->incalls);
 	if(i == nil)
 		return -1;
-	print("%s: recvp %d\n", l->ds, i->slot);
+	print("%s: recvp slot %d\n", l->ds, i->slot);
 	i->pid = Unset;
 
 redux:
@@ -397,6 +398,7 @@
 freeserver(Listen *l)
 {
 	cleanserver(l);
+	free(l->es);
 	free(l->ds);
 	free(l->proto);
 	free(l);
@@ -475,14 +477,15 @@
 			del = 1;
 
 		for(xx = head; x = *xx; xx = &x->next)
-			if(strcmp(x->ds, d[i].name) == 0)
+			if(strcmp(x->es, d[i].name) == 0)
 				break;
 		if(x != nil)
 			x->mark = del;
 		if(x == nil && !del){
 			x = *xx = malloc(sizeof *x);
 			memset(x, 0, sizeof *x);
-			x->ds = strdup(d[i].name);
+			x->es = strdup(d[i].name);
+			x->ds = smprint("%s/%s", l->netdir, d[i].name);
 			x->proto = strdup(d[i].name);
 			if((s = strchr(x->proto, '!')) != nil)
 				*s = 0;