xref: /illumos-gate/usr/src/lib/libc/port/threads/pthr_rwlock.c (revision 2983dda76a6d296fdb560c88114fe41caad1b84f)
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 /*
23  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 #include "lint.h"
30 #include "thr_uberdata.h"
31 
32 /*
33  * UNIX98
34  * pthread_rwlockattr_init: allocates the mutex attribute object and
35  * initializes it with the default values.
36  */
37 int
38 pthread_rwlockattr_init(pthread_rwlockattr_t *attr)
39 {
40 	rwlattr_t *ap;
41 
42 	if ((ap = lmalloc(sizeof (rwlattr_t))) == NULL)
43 		return (ENOMEM);
44 	ap->pshared = DEFAULT_TYPE;
45 	attr->__pthread_rwlockattrp = ap;
46 	return (0);
47 }
48 
49 /*
50  * UNIX98
51  * pthread_rwlockattr_destroy: frees the rwlock attribute object and
52  * invalidates it with NULL value.
53  */
54 int
55 pthread_rwlockattr_destroy(pthread_rwlockattr_t *attr)
56 {
57 	if (attr == NULL || attr->__pthread_rwlockattrp == NULL)
58 		return (EINVAL);
59 	lfree(attr->__pthread_rwlockattrp, sizeof (rwlattr_t));
60 	attr->__pthread_rwlockattrp = NULL;
61 	return (0);
62 }
63 
64 /*
65  * UNIX98
66  * pthread_rwlockattr_setpshared: sets the shared attr to PRIVATE or SHARED.
67  */
68 int
69 pthread_rwlockattr_setpshared(pthread_rwlockattr_t *attr, int pshared)
70 {
71 	rwlattr_t *ap;
72 
73 	if (attr != NULL && (ap = attr->__pthread_rwlockattrp) != NULL &&
74 	    (pshared == PTHREAD_PROCESS_PRIVATE ||
75 	    pshared == PTHREAD_PROCESS_SHARED)) {
76 		ap->pshared = pshared;
77 		return (0);
78 	}
79 	return (EINVAL);
80 }
81 
82 /*
83  * UNIX98
84  * pthread_rwlockattr_getpshared: gets the shared attr.
85  */
86 int
87 pthread_rwlockattr_getpshared(const pthread_rwlockattr_t *attr, int *pshared)
88 {
89 	rwlattr_t *ap;
90 
91 	if (attr != NULL && (ap = attr->__pthread_rwlockattrp) != NULL &&
92 	    pshared != NULL) {
93 		*pshared = ap->pshared;
94 		return (0);
95 	}
96 	return (EINVAL);
97 }
98 
99 /*
100  * UNIX98
101  * pthread_rwlock_init: Initializes the rwlock object. It copies the
102  * pshared attr into type argument and calls rwlock_init().
103  */
104 int
105 pthread_rwlock_init(pthread_rwlock_t *_RESTRICT_KYWD rwlock,
106     const pthread_rwlockattr_t *_RESTRICT_KYWD attr)
107 {
108 	rwlattr_t *ap;
109 	int type;
110 
111 	if (attr == NULL)
112 		type = DEFAULT_TYPE;
113 	else if ((ap = attr->__pthread_rwlockattrp) != NULL)
114 		type = ap->pshared;
115 	else
116 		return (EINVAL);
117 
118 	return (rwlock_init((rwlock_t *)rwlock, type, NULL));
119 }
120