1/* Copyright (C) 2002-2021 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3 Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
4
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
9
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <https://www.gnu.org/licenses/>. */
18
19#include "pthreadP.h"
20#include <string.h>
21#include <pthread-offsets.h>
22
23
24static const struct pthread_rwlockattr default_rwlockattr =
25 {
26 .lockkind = PTHREAD_RWLOCK_DEFAULT_NP,
27 .pshared = PTHREAD_PROCESS_PRIVATE
28 };
29
30
31/* See pthread_rwlock_common.c. */
32int
33__pthread_rwlock_init (pthread_rwlock_t *rwlock,
34 const pthread_rwlockattr_t *attr)
35{
36 ASSERT_TYPE_SIZE (pthread_rwlock_t, __SIZEOF_PTHREAD_RWLOCK_T);
37
38 /* The __flags is the only field where its offset should be checked to
39 avoid ABI breakage with static initializers. */
40 ASSERT_PTHREAD_INTERNAL_OFFSET (pthread_rwlock_t, __data.__flags,
41 __PTHREAD_RWLOCK_FLAGS_OFFSET);
42 ASSERT_PTHREAD_INTERNAL_MEMBER_SIZE (pthread_rwlock_t, __data.__flags,
43 int);
44
45 const struct pthread_rwlockattr *iattr;
46
47 iattr = ((const struct pthread_rwlockattr *) attr) ?: &default_rwlockattr;
48
49 memset (rwlock, '\0', sizeof (*rwlock));
50
51 rwlock->__data.__flags = iattr->lockkind;
52
53 /* The value of __SHARED in a private rwlock must be zero. */
54 rwlock->__data.__shared = (iattr->pshared != PTHREAD_PROCESS_PRIVATE);
55
56 return 0;
57}
58strong_alias (__pthread_rwlock_init, pthread_rwlock_init)
59