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/* Copyright (C) 2003, 2004, 2007, 2008 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Martin Schwidefsky <schwidefsky@de.ibm.com>, 2003.
OpenSolaris bits contributed by David Bartley
<dtbartle@csclub.uwaterloo.ca>, 2008.
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, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#include <errno.h>
#include <pthreadP.h>
#include <stdio.h>
#include <not-cancel.h>
/* Wait on barrier. */
int
pthread_barrier_wait (barrier)
pthread_barrier_t *barrier;
{
struct pthread_barrier *ibarrier = (struct pthread_barrier *) barrier;
int errval = __pthread_mutex_lock (&ibarrier->mutex);
if (errval != 0)
return errval;
/* Make sure barrier is not exiting. */
while (ibarrier->flag & BARRIER_EXITING)
{
errval = __cond_reltimedwait_internal ((cond_t *)&ibarrier->cond,
(mutex_t *)&ibarrier->mutex, NULL, 0);
if (errval != EINTR && errval != 0)
{
(void)__pthread_mutex_unlock (&ibarrier->mutex);
return errval;
}
}
/* A thread entered the barrier. */
--ibarrier->left;
if (ibarrier->left == 0)
{
/* Increment the event counter to avoid invalid wake-ups and tell the
current waiters that it is their turn. Also reset the barrier. */
++ibarrier->curr_event;
ibarrier->flag |= BARRIER_EXITING;
/* Wake other threads. */
(void)pthread_cond_broadcast (&ibarrier->cond);
errval = PTHREAD_BARRIER_SERIAL_THREAD;
}
else
{
/* Wait until the current barrier event is done. */
int curr_event = ibarrier->curr_event;
do
{
errval = __cond_reltimedwait_internal ((cond_t *)&ibarrier->cond,
(mutex_t *)&ibarrier->mutex, NULL, 0);
if (errval != EINTR && errval != 0)
{
(void)__pthread_mutex_unlock (&ibarrier->mutex);
return errval;
}
}
while (curr_event == ibarrier->curr_event);
}
/* If we are the last thread notify barrier waiters. */
if (++ibarrier->left == ibarrier->init_count)
{
ibarrier->flag &= ~BARRIER_EXITING;
(void)pthread_cond_broadcast (&ibarrier->cond);
}
(void)__pthread_mutex_unlock (&ibarrier->mutex);
return errval;
}
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