usr/src/lib/libc/port/threads/pthr_rwlock.c

   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 #include "lint.h"
  28 #include "thr_uberdata.h"
  29
  30 /*
  31  * UNIX98
  32  * pthread_rwlockattr_init: allocates the mutex attribute object and
  33  * initializes it with the default values.
  34  */
  35 int
  36 pthread_rwlockattr_init(pthread_rwlockattr_t *attr)
  37 {
  38         rwlattr_t *ap;
  39
  40         if ((ap = lmalloc(sizeof (rwlattr_t))) == NULL)
  41                 return (ENOMEM);
  42         ap->pshared = PTHREAD_PROCESS_PRIVATE;
  43         attr->__pthread_rwlockattrp = ap;
  44         return (0);
  45 }
  46
  47 /*
  48  * UNIX98
  49  * pthread_rwlockattr_destroy: frees the rwlock attribute object and
  50  * invalidates it with NULL value.
  51  */
  52 int
  53 pthread_rwlockattr_destroy(pthread_rwlockattr_t *attr)
  54 {
  55         if (attr == NULL || attr->__pthread_rwlockattrp == NULL)
  56                 return (EINVAL);
  57         lfree(attr->__pthread_rwlockattrp, sizeof (rwlattr_t));
  58         attr->__pthread_rwlockattrp = NULL;
  59         return (0);
  60 }
  61
  62 /*
  63  * UNIX98
  64  * pthread_rwlockattr_setpshared: sets the shared attr to PRIVATE or SHARED.
  65  */
  66 int
  67 pthread_rwlockattr_setpshared(pthread_rwlockattr_t *attr, int pshared)
  68 {
  69         rwlattr_t *ap;
  70
  71         if (attr != NULL && (ap = attr->__pthread_rwlockattrp) != NULL &&
  72             (pshared == PTHREAD_PROCESS_PRIVATE ||
  73             pshared == PTHREAD_PROCESS_SHARED)) {
  74                 ap->pshared = pshared;
  75                 return (0);
  76         }
  77         return (EINVAL);
  78 }
  79
  80 /*
  81  * UNIX98
  82  * pthread_rwlockattr_getpshared: gets the shared attr.
  83  */
  84 int
  85 pthread_rwlockattr_getpshared(const pthread_rwlockattr_t *attr, int *pshared)
  86 {
  87         rwlattr_t *ap;
  88
  89         if (attr != NULL && (ap = attr->__pthread_rwlockattrp) != NULL &&
  90             pshared != NULL) {
  91                 *pshared = ap->pshared;
  92                 return (0);
  93         }
  94         return (EINVAL);
  95 }
  96
  97 /*
  98  * UNIX98
  99  * pthread_rwlock_init: Initializes the rwlock object. It copies the
 100  * pshared attr into type argument and calls rwlock_init().
 101  */
 102 int
 103 pthread_rwlock_init(pthread_rwlock_t *_RESTRICT_KYWD rwlock,
 104     const pthread_rwlockattr_t *_RESTRICT_KYWD attr)
 105 {
 106         rwlattr_t *ap;
 107         int type;
 108
 109         if (attr == NULL)
 110                 type = PTHREAD_PROCESS_PRIVATE;
 111         else if ((ap = attr->__pthread_rwlockattrp) != NULL)
 112                 type = ap->pshared;
 113         else
 114                 return (EINVAL);
 115
 116         return (rwlock_init((rwlock_t *)rwlock, type, NULL));
 117 }