nptl/pthread_mutexattr_setprotocol.c


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/* Change priority protocol setting in pthread_mutexattr_t.
   Copyright (C) 2006-2020 Free Software Foundation, Inc.
   This file is part of the GNU C Library.
   Contributed by Jakub Jelinek <jakub@redhat.com>, 2006.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public
   License along with the GNU C Library; if not, see
   <https://www.gnu.org/licenses/>.  */

#include <errno.h>
#include <pthreadP.h>


int
pthread_mutexattr_setprotocol (pthread_mutexattr_t *attr, int protocol)
{
  if (protocol != PTHREAD_PRIO_NONE
      && protocol != PTHREAD_PRIO_INHERIT
      && __builtin_expect (protocol != PTHREAD_PRIO_PROTECT, 0))
    return EINVAL;

  struct pthread_mutexattr *iattr = (struct pthread_mutexattr *) attr;

  iattr->mutexkind = ((iattr->mutexkind & ~PTHREAD_MUTEXATTR_PROTOCOL_MASK)
		      | (protocol << PTHREAD_MUTEXATTR_PROTOCOL_SHIFT));

  return 0;
}