xref: /illumos-gate/usr/src/cmd/nscd/nscd_wait.c (revision c16fc6609d9aa72229802524dc1d8c4ead6e9d2a)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 #pragma ident	"%Z%%M%	%I%	%E% SMI"
27 
28 /*
29  * routines to wait and wake up a client waiting on a list for a
30  * name service request
31  */
32 #include "cache.h"
33 
34 int
35 nscd_wait(waiter_t *wchan,  mutex_t *lock, uint8_t *key)
36 {
37 	waiter_t mywait;
38 	(void) cond_init(&(mywait.w_waitcv), USYNC_THREAD, 0);
39 	mywait.w_key = key;
40 	mywait.w_next = wchan->w_next;
41 	mywait.w_prev = wchan;
42 	if (mywait.w_next)
43 		mywait.w_next->w_prev = &mywait;
44 	wchan->w_next = &mywait;
45 
46 	while (*key & ST_PENDING)
47 		(void) cond_wait(&(mywait.w_waitcv), lock);
48 	if (mywait.w_prev)
49 		mywait.w_prev->w_next = mywait.w_next;
50 	if (mywait.w_next)
51 		mywait.w_next->w_prev = mywait.w_prev;
52 	return (0);
53 }
54 
55 int
56 nscd_signal(waiter_t *wchan, uint8_t *key)
57 {
58 	int c = 0;
59 	waiter_t *tmp = wchan->w_next;
60 
61 	while (tmp) {
62 		if (tmp->w_key == key) {
63 			(void) cond_signal(&(tmp->w_waitcv));
64 			c++;
65 		}
66 		tmp = tmp->w_next;
67 	}
68 
69 	return (c);
70 }
71