1/* $NetBSD: callback.h,v 1.3 2007/07/09 21:11:32 ad Exp $ */
2
3/*-
4 * Copyright (c)2006 YAMAMOTO Takashi,
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29#ifndef _SYS_CALLBACK_H_
30#define _SYS_CALLBACK_H_
31
32#include <sys/queue.h>
33#include <sys/mutex.h>
34#include <sys/condvar.h>
35
36struct callback_entry {
37 TAILQ_ENTRY(callback_entry) ce_q;
38 int (*ce_func)(struct callback_entry *, void *, void *);
39 void *ce_obj;
40};
41
42struct callback_head {
43 kmutex_t ch_lock;
44 kcondvar_t ch_cv;
45 TAILQ_HEAD(, callback_entry) ch_q;
46 struct callback_entry *ch_next;
47 int ch_nentries;
48 int ch_running;
49 int ch_flags;
50};
51
52/* return values of ce_func */
53#define CALLBACK_CHAIN_CONTINUE 0
54#define CALLBACK_CHAIN_ABORT 1
55
56int callback_run_roundrobin(struct callback_head *, void *);
57void callback_register(struct callback_head *, struct callback_entry *,
58 void *, int (*)(struct callback_entry *, void *, void *));
59void callback_unregister(struct callback_head *, struct callback_entry *);
60void callback_head_init(struct callback_head *, int);
61void callback_head_destroy(struct callback_head *);
62
63#endif /* !_SYS_CALLBACK_H_ */
64