nptl/pthread_mutexattr_setpshared.c

   1 /* Copyright (C) 2002-2020 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 <errno.h>
  20 #include <pthreadP.h>
  21 #include <futex-internal.h>
  22
  23
  24 int
  25 pthread_mutexattr_setpshared (pthread_mutexattr_t *attr, int pshared)
  26 {
  27   struct pthread_mutexattr *iattr;
  28
  29   int err = futex_supports_pshared (pshared);
  30   if (err != 0)
  31     return err;
  32
  33   iattr = (struct pthread_mutexattr *) attr;
  34
  35   if (pshared == PTHREAD_PROCESS_PRIVATE)
  36     iattr->mutexkind &= ~PTHREAD_MUTEXATTR_FLAG_PSHARED;
  37   else
  38     iattr->mutexkind |= PTHREAD_MUTEXATTR_FLAG_PSHARED;
  39
  40   return 0;
  41 }