libpthread/nptl/pthread_mutexattr_setrobust.c

   1 /* Copyright (C) 2005, 2010 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Ulrich Drepper <drepper@redhat.com>, 2005.
   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    <http://www.gnu.org/licenses/>.  */
  18
  19 #include <errno.h>
  20 #include <pthreadP.h>
  21
  22
  23 int
  24 pthread_mutexattr_setrobust (
  25      pthread_mutexattr_t *attr,
  26      int robustness)
  27 {
  28   if (robustness != PTHREAD_MUTEX_STALLED_NP
  29       && __builtin_expect (robustness != PTHREAD_MUTEX_ROBUST_NP, 0))
  30     return EINVAL;
  31
  32   struct pthread_mutexattr *iattr = (struct pthread_mutexattr *) attr;
  33
  34   /* We use bit 30 to signal whether the mutex is going to be
  35      robust or not.  */
  36   if (robustness == PTHREAD_MUTEX_STALLED_NP)
  37     iattr->mutexkind &= ~PTHREAD_MUTEXATTR_FLAG_ROBUST;
  38   else
  39     iattr->mutexkind |= PTHREAD_MUTEXATTR_FLAG_ROBUST;
  40
  41   return 0;
  42 }
  43 weak_alias (pthread_mutexattr_setrobust, pthread_mutexattr_setrobust_np)