xref: /freebsd/include/semaphore.h (revision a812392203d7c4c3f0db9d8a0f3391374c49c71f)
1 /*
2  * Copyright (c) 2010 David Xu <davidxu@freebsd.org>
3  *
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice unmodified, this list of conditions, and the following
11  *    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 ``AS IS'' AND ANY EXPRESS OR
17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26  *
27  * $FreeBSD$
28  */
29 
30 /* semaphore.h: POSIX 1003.1b semaphores */
31 
32 #ifndef _SEMAPHORE_H_
33 #define _SEMAPHORE_H_
34 
35 #include <sys/cdefs.h>
36 #include <sys/_types.h>
37 #include <sys/_umtx.h>
38 
39 struct _sem {
40 	__uint32_t	_magic;
41 	struct _usem2	_kern;
42 	__uint32_t	_padding;	/* Preserve structure size */
43 };
44 
45 typedef	struct _sem	sem_t;
46 
47 #define	SEM_FAILED	((sem_t *)0)
48 #define	SEM_VALUE_MAX	__INT_MAX
49 
50 struct timespec;
51 
52 __BEGIN_DECLS
53 int	 sem_close(sem_t *);
54 int	 sem_destroy(sem_t *);
55 int	 sem_getvalue(sem_t * __restrict, int * __restrict);
56 int	 sem_init(sem_t *, int, unsigned int);
57 sem_t	*sem_open(const char *, int, ...);
58 int	 sem_post(sem_t *);
59 int	 sem_timedwait(sem_t * __restrict, const struct timespec * __restrict);
60 int	 sem_trywait(sem_t *);
61 int	 sem_unlink(const char *);
62 int	 sem_wait(sem_t *);
63 __END_DECLS
64 
65 #endif /* !_SEMAPHORE_H_ */
66