1 fd04aace 2003-11-23 devnull #include <u.h>
 2 fd04aace 2003-11-23 devnull #include <libc.h>
 3 fd04aace 2003-11-23 devnull #include "9proc.h"
 4 fd04aace 2003-11-23 devnull 
 5 fd04aace 2003-11-23 devnull static Lock rendlock;
 6 fd04aace 2003-11-23 devnull static Uproc *rendhash[RENDHASH];
 7 fd04aace 2003-11-23 devnull 
 8 fd04aace 2003-11-23 devnull ulong
 9 fd04aace 2003-11-23 devnull rendezvous(ulong tag, ulong val)
10 fd04aace 2003-11-23 devnull {
11 fd04aace 2003-11-23 devnull 	char c;
12 fd04aace 2003-11-23 devnull 	ulong ret;
13 fd04aace 2003-11-23 devnull 	Uproc *t, *self, **l;
14 fd04aace 2003-11-23 devnull 
15 fd04aace 2003-11-23 devnull 	self = _p9uproc();
16 fd04aace 2003-11-23 devnull 	lock(&rendlock);
17 fd04aace 2003-11-23 devnull 	l = &rendhash[tag%RENDHASH];
18 fd04aace 2003-11-23 devnull 	for(t=*l; t; l=&t->rendhash, t=*l){
19 fd04aace 2003-11-23 devnull 		if(t->rendtag==tag){
20 fd04aace 2003-11-23 devnull 			*l = t->rendhash;
21 fd04aace 2003-11-23 devnull 			ret = t->rendval;
22 fd04aace 2003-11-23 devnull 			t->rendval = val;
23 fd04aace 2003-11-23 devnull 			t->rendtag++;
24 fd04aace 2003-11-23 devnull 			c = 0;
25 fd04aace 2003-11-23 devnull 			unlock(&rendlock);
26 fd04aace 2003-11-23 devnull 			write(t->pipe[1], &c, 1);
27 fd04aace 2003-11-23 devnull 			return ret;
28 fd04aace 2003-11-23 devnull 		}
29 fd04aace 2003-11-23 devnull 	}
30 fd04aace 2003-11-23 devnull 
31 fd04aace 2003-11-23 devnull 	/* Going to sleep here. */
32 fd04aace 2003-11-23 devnull 	t = self;
33 fd04aace 2003-11-23 devnull 	t->rendtag = tag;
34 fd04aace 2003-11-23 devnull 	t->rendval = val;
35 fd04aace 2003-11-23 devnull 	t->rendhash = *l;
36 fd04aace 2003-11-23 devnull 	*l = t;
37 fd04aace 2003-11-23 devnull 	unlock(&rendlock);
38 fd04aace 2003-11-23 devnull 	do
39 fd04aace 2003-11-23 devnull 		read(t->pipe[0], &c, 1);
40 fd04aace 2003-11-23 devnull 	while(t->rendtag == tag);
41 fd04aace 2003-11-23 devnull 	return t->rendval;
42 fd04aace 2003-11-23 devnull }