nptl/pthread_barrier_init.c

   1 /* Copyright (C) 2002-2022 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, see
  16    <https://www.gnu.org/licenses/>.  */
  17
  18 #include <errno.h>
  19 #include "pthreadP.h"
  20 #include <futex-internal.h>
  21 #include <kernel-features.h>
  22 #include <shlib-compat.h>
  23
  24 static const struct pthread_barrierattr default_barrierattr =
  25   {
  26     .pshared = PTHREAD_PROCESS_PRIVATE
  27   };
  28
  29
  30 int
  31 ___pthread_barrier_init (pthread_barrier_t *barrier,
  32                         const pthread_barrierattr_t *attr, unsigned int count)
  33 {
  34   ASSERT_TYPE_SIZE (pthread_barrier_t, __SIZEOF_PTHREAD_BARRIER_T);
  35   ASSERT_PTHREAD_INTERNAL_SIZE (pthread_barrier_t,
  36                                 struct pthread_barrier);
  37
  38   struct pthread_barrier *ibarrier;
  39
  40   /* XXX EINVAL is not specified by POSIX as a possible error code for COUNT
  41      being too large.  See pthread_barrier_wait for the reason for the
  42      comparison with BARRIER_IN_THRESHOLD.  */
  43   if (__glibc_unlikely (count == 0 || count >= BARRIER_IN_THRESHOLD))
  44     return EINVAL;
  45
  46   const struct pthread_barrierattr *iattr
  47     = (attr != NULL
  48        ? (struct pthread_barrierattr *) attr
  49        : &default_barrierattr);
  50
  51   ibarrier = (struct pthread_barrier *) barrier;
  52
  53   /* Initialize the individual fields.  */
  54   ibarrier->in = 0;
  55   ibarrier->out = 0;
  56   ibarrier->count = count;
  57   ibarrier->current_round = 0;
  58   ibarrier->shared = (iattr->pshared == PTHREAD_PROCESS_PRIVATE
  59                       ? FUTEX_PRIVATE : FUTEX_SHARED);
  60
  61   return 0;
  62 }
  63 versioned_symbol (libc, ___pthread_barrier_init, pthread_barrier_init,
  64                   GLIBC_2_34);
  65 libc_hidden_ver (___pthread_barrier_init, __pthread_barrier_init)
  66 #ifndef SHARED
  67 strong_alias (___pthread_barrier_init, __pthread_barrier_init)
  68 #endif
  69
  70 #if OTHER_SHLIB_COMPAT (libpthread, GLIBC_2_2, GLIBC_2_34)
  71 compat_symbol (libpthread, ___pthread_barrier_init, pthread_barrier_init,
  72                GLIBC_2_2);
  73 #endif