2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
4 * Copyright (C) 2001 Jason Evans <jasone@freebsd.org>. All rights reserved.
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
9 * 1. Redistributions of source code must retain the above copyright
10 * notice(s), this list of conditions and the following disclaimer as
11 * the first lines of this file unmodified other than the possible
12 * addition of one or more copyright notices.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice(s), this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
17 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER(S) ``AS IS'' AND ANY
18 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
19 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
20 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) BE LIABLE FOR ANY
21 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
22 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
23 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
24 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
35 #include <sys/queue.h>
36 #include <sys/_lock.h>
37 #include <sys/_mutex.h>
38 #include <sys/condvar.h>
41 struct mtx sema_mtx; /* General protection lock. */
42 struct cv sema_cv; /* Waiters. */
43 int sema_waiters; /* Number of waiters. */
44 int sema_value; /* Semaphore value. */
48 void sema_init(struct sema *sema, int value, const char *description);
49 void sema_destroy(struct sema *sema);
50 void _sema_post(struct sema *sema, const char *file, int line);
51 void _sema_wait(struct sema *sema, const char *file, int line);
52 int _sema_timedwait(struct sema *sema, int timo, const char *file, int
54 int _sema_trywait(struct sema *sema, const char *file, int line);
55 int sema_value(struct sema *sema);
57 #define sema_post(sema) _sema_post((sema), LOCK_FILE, LOCK_LINE)
58 #define sema_wait(sema) _sema_wait((sema), LOCK_FILE, LOCK_LINE)
59 #define sema_timedwait(sema, timo) \
60 _sema_timedwait((sema), (timo), LOCK_FILE, LOCK_LINE)
61 #define sema_trywait(sema) _sema_trywait((sema), LOCK_FILE, LOCK_LINE)
64 #endif /* _SYS_SEMA_H_ */