xref: /freebsd/lib/libstdthreads/mtx.c (revision 2008043f386721d58158e37e0d7e50df8095942d)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2011 Ed Schouten <ed@FreeBSD.org>
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 #include <sys/cdefs.h>
30 #include <errno.h>
31 #include <pthread.h>
32 
33 #include "threads.h"
34 
35 void
36 mtx_destroy(mtx_t *mtx)
37 {
38 
39 	(void)pthread_mutex_destroy(mtx);
40 }
41 
42 int
43 mtx_init(mtx_t *mtx, int type)
44 {
45 	pthread_mutexattr_t attr;
46 	int mt;
47 
48 	switch (type) {
49 	case mtx_plain:
50 	case mtx_timed:
51 		mt = PTHREAD_MUTEX_NORMAL;
52 		break;
53 	case mtx_plain | mtx_recursive:
54 	case mtx_timed | mtx_recursive:
55 		mt = PTHREAD_MUTEX_RECURSIVE;
56 		break;
57 	default:
58 		return (thrd_error);
59 	}
60 
61 	if (pthread_mutexattr_init(&attr) != 0)
62 		return (thrd_error);
63 	if (pthread_mutexattr_settype(&attr, mt) != 0)
64 		return (thrd_error);
65 	if (pthread_mutex_init(mtx, &attr) != 0)
66 		return (thrd_error);
67 	return (thrd_success);
68 }
69 
70 int
71 mtx_lock(mtx_t *mtx)
72 {
73 
74 	if (pthread_mutex_lock(mtx) != 0)
75 		return (thrd_error);
76 	return (thrd_success);
77 }
78 
79 int
80 mtx_timedlock(mtx_t *restrict mtx, const struct timespec *restrict ts)
81 {
82 
83 	switch (pthread_mutex_timedlock(mtx, ts)) {
84 	case 0:
85 		return (thrd_success);
86 	case ETIMEDOUT:
87 		return (thrd_timedout);
88 	default:
89 		return (thrd_error);
90 	}
91 }
92 
93 int
94 mtx_trylock(mtx_t *mtx)
95 {
96 
97 	switch (pthread_mutex_trylock(mtx)) {
98 	case 0:
99 		return (thrd_success);
100 	case EBUSY:
101 		return (thrd_busy);
102 	default:
103 		return (thrd_error);
104 	}
105 }
106 
107 int
108 mtx_unlock(mtx_t *mtx)
109 {
110 
111 	if (pthread_mutex_unlock(mtx) != 0)
112 		return (thrd_error);
113 	return (thrd_success);
114 }
115