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 2007 Sun Microsystems, Inc. All rights reserved.
23 * Use is subject to license terms.
24 */
25
26 /*
27 * routines to wait and wake up a client waiting on a list for a
28 * name service request
29 */
30 #include "cache.h"
31
32 int
nscd_wait(nsc_ctx_t * ctx,nsc_db_t * nscdb,nsc_entry_t * entry)33 nscd_wait(nsc_ctx_t *ctx, nsc_db_t *nscdb, nsc_entry_t *entry)
34 {
35 waiter_t mywait;
36 waiter_t *wchan = &nscdb->db_wait;
37
38 (void) cond_init(&(mywait.w_waitcv), USYNC_THREAD, 0);
39 mywait.w_key = entry;
40 mywait.w_signaled = 0;
41 mywait.w_next = wchan->w_next;
42 mywait.w_prev = wchan;
43 if (mywait.w_next)
44 mywait.w_next->w_prev = &mywait;
45 wchan->w_next = &mywait;
46
47 (void) mutex_lock(&ctx->stats_mutex);
48 ctx->stats.wait_count++;
49 (void) mutex_unlock(&ctx->stats_mutex);
50
51 while (!mywait.w_signaled)
52 (void) cond_wait(&(mywait.w_waitcv), &nscdb->db_mutex);
53 if (mywait.w_prev)
54 mywait.w_prev->w_next = mywait.w_next;
55 if (mywait.w_next)
56 mywait.w_next->w_prev = mywait.w_prev;
57 return (0);
58 }
59
60 int
nscd_signal(nsc_ctx_t * ctx,nsc_db_t * nscdb,nsc_entry_t * entry)61 nscd_signal(nsc_ctx_t *ctx, nsc_db_t *nscdb, nsc_entry_t *entry)
62 {
63 int c = 0;
64 waiter_t *wchan = &nscdb->db_wait;
65 waiter_t *tmp = wchan->w_next;
66
67 while (tmp) {
68 if (tmp->w_key == entry) {
69 (void) cond_signal(&(tmp->w_waitcv));
70 tmp->w_signaled = 1;
71
72 (void) mutex_lock(&ctx->stats_mutex);
73 ctx->stats.wait_count--;
74 (void) mutex_unlock(&ctx->stats_mutex);
75 c++;
76 }
77 tmp = tmp->w_next;
78 }
79
80 return (c);
81 }
82