1 /* rwlock type.  Generic version.
2    Copyright (C) 2002-2022 Free Software Foundation, Inc.
3    This file is part of the GNU C Library.
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 #ifndef _BITS_TYPES_STRUCT___PTHREAD_RWLOCK_H
20 #define _BITS_TYPES_STRUCT___PTHREAD_RWLOCK_H
21 
22 #include <bits/types/__pthread_spinlock_t.h>
23 
24 /* User visible part of a rwlock.  If __held is not held and readers
25    is 0, then the lock is unlocked.  If __held is held and readers is
26    0, then the lock is held by a writer.  If __held is held and
27    readers is greater than 0, then the lock is held by READERS
28    readers.  */
29 struct __pthread_rwlock
30 {
31   __pthread_spinlock_t __held;
32   __pthread_spinlock_t __lock;
33   int __readers;
34   struct __pthread *__readerqueue;
35   struct __pthread *__writerqueue;
36   struct __pthread_rwlockattr *__attr;
37   void *__data;
38 };
39 
40 /* Initializer for a rwlock.  */
41 #define __PTHREAD_RWLOCK_INITIALIZER \
42     { __PTHREAD_SPIN_LOCK_INITIALIZER, __PTHREAD_SPIN_LOCK_INITIALIZER, 0, 0, 0, 0, 0 }
43 
44 
45 #endif /* bits/types/struct___pthread_rwlock.h */
46