nptl/sem_init.c

   1 /* Copyright (C) 2002-2014 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    <http://www.gnu.org/licenses/>.  */
  18
  19 #include <errno.h>
  20 #include <semaphore.h>
  21 #include <lowlevellock.h>
  22 #include <shlib-compat.h>
  23 #include "semaphoreP.h"
  24 #include <kernel-features.h>
  25
  26
  27 int
  28 __new_sem_init (sem, pshared, value)
  29      sem_t *sem;
  30      int pshared;
  31      unsigned int value;
  32 {
  33   /* Parameter sanity check.  */
  34   if (__glibc_unlikely (value > SEM_VALUE_MAX))
  35     {
  36       __set_errno (EINVAL);
  37       return -1;
  38     }
  39
  40   /* Map to the internal type.  */
  41   struct new_sem *isem = (struct new_sem *) sem;
  42
  43   /* Use the values the user provided.  */
  44   isem->value = value;
  45 #ifdef __ASSUME_PRIVATE_FUTEX
  46   isem->private = pshared ? 0 : FUTEX_PRIVATE_FLAG;
  47 #else
  48   isem->private = pshared ? 0 : THREAD_GETMEM (THREAD_SELF,
  49                                                header.private_futex);
  50 #endif
  51
  52   isem->nwaiters = 0;
  53
  54   return 0;
  55 }
  56 versioned_symbol (libpthread, __new_sem_init, sem_init, GLIBC_2_1);
  57
  58
  59
  60 #if SHLIB_COMPAT(libpthread, GLIBC_2_0, GLIBC_2_1)
  61 int
  62 attribute_compat_text_section
  63 __old_sem_init (sem, pshared, value)
  64      sem_t *sem;
  65      int pshared;
  66      unsigned int value;
  67 {
  68   /* Parameter sanity check.  */
  69   if (__glibc_unlikely (value > SEM_VALUE_MAX))
  70     {
  71       __set_errno (EINVAL);
  72       return -1;
  73     }
  74
  75   /* Map to the internal type.  */
  76   struct old_sem *isem = (struct old_sem *) sem;
  77
  78   /* Use the value the user provided.  */
  79   isem->value = value;
  80
  81   /* We cannot store the PSHARED attribute.  So we always use the
  82      operations needed for shared semaphores.  */
  83
  84   return 0;
  85 }
  86 compat_symbol (libpthread, __old_sem_init, sem_init, GLIBC_2_0);
  87 #endif