nptl/old_pthread_cond_wait.c

   1 /* Copyright (C) 2002, 2003, 2007 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, write to the Free
  17    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  18    02111-1307 USA.  */
  19
  20 #include <errno.h>
  21 #include <stdlib.h>
  22 #include "pthreadP.h"
  23 #include <atomic.h>
  24 #include <shlib-compat.h>
  25
  26
  27 #if SHLIB_COMPAT(libpthread, GLIBC_2_0, GLIBC_2_3_2)
  28 int
  29 __pthread_cond_wait_2_0 (cond, mutex)
  30      pthread_cond_2_0_t *cond;
  31      pthread_mutex_t *mutex;
  32 {
  33   if (cond->cond == NULL)
  34     {
  35       pthread_cond_t *newcond;
  36
  37 #if LLL_LOCK_INITIALIZER == 0
  38       newcond = (pthread_cond_t *) calloc (sizeof (pthread_cond_t), 1);
  39       if (newcond == NULL)
  40         return ENOMEM;
  41 #else
  42       newcond = (pthread_cond_t *) malloc (sizeof (pthread_cond_t));
  43       if (newcond == NULL)
  44         return ENOMEM;
  45
  46       /* Initialize the condvar.  */
  47       (void) pthread_cond_init (newcond, NULL);
  48 #endif
  49
  50       if (atomic_compare_and_exchange_bool_acq (&cond->cond, newcond, NULL))
  51         /* Somebody else just initialized the condvar.  */
  52         free (newcond);
  53     }
  54
  55   return __pthread_cond_wait (cond->cond, mutex);
  56 }
  57 compat_symbol (libpthread, __pthread_cond_wait_2_0, pthread_cond_wait,
  58                GLIBC_2_0);
  59 #endif