nptl/pthread_rwlock_init.c

   1 /* Copyright (C) 2002 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, write to the Free
  17    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  18    02111-1307 USA.  */
  19
  20 #include "pthreadP.h"
  21
  22
  23 static const struct pthread_rwlockattr default_attr =
  24   {
  25     .lockkind = PTHREAD_RWLOCK_DEFAULT_NP,
  26     .pshared = PTHREAD_PROCESS_PRIVATE
  27   };
  28
  29
  30 int
  31 __pthread_rwlock_init (rwlock, attr)
  32      pthread_rwlock_t *rwlock;
  33      const pthread_rwlockattr_t *attr;
  34 {
  35   const struct pthread_rwlockattr *iattr;
  36
  37   iattr = ((const struct pthread_rwlockattr *) attr) ?: &default_attr;
  38
  39   rwlock->__data.__lock = 0;
  40   rwlock->__data.__flags
  41     = iattr->lockkind == PTHREAD_RWLOCK_PREFER_WRITER_NONRECURSIVE_NP;
  42   rwlock->__data.__nr_readers = 0;
  43   rwlock->__data.__writer = 0;
  44   rwlock->__data.__readers_wakeup = 0;
  45   rwlock->__data.__writer_wakeup = 0;
  46   rwlock->__data.__nr_readers_queued = 0;
  47   rwlock->__data.__nr_writers_queued = 0;
  48
  49   return 0;
  50 }
  51 strong_alias (__pthread_rwlock_init, pthread_rwlock_init)