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/* Tests for pthread_barrier_* functions.
Copyright (C) 2000 Free Software Foundation, Inc.
Contributed by Kaz Kylheku <kaz@ashi.footprints.net>, 2000.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 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
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If not,
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#include <errno.h>
#include <error.h>
#include <stdio.h>
#include <stdlib.h>
#include <pthread.h>
#define NUM_THREADS 10
#define NUM_ITERS 500
static void *thread (void *);
static pthread_barrier_t barrier;
int
main (void)
{
pthread_t th;
int i;
if (pthread_barrier_init (&barrier, NULL, NUM_THREADS + 1) != 0)
error (EXIT_FAILURE, 0, "cannot initialize barrier");
for (i = 0; i < NUM_THREADS; i++)
{
if (pthread_create (&th, NULL, thread, NULL) != 0)
error (EXIT_FAILURE, 0, "cannot create thread");
}
(void) thread (NULL);
/* notreached */
return 0;
}
static void *
thread (void *arg)
{
int i;
pthread_t self = pthread_self ();
static pthread_t last_serial_thread;
static int linecount; /* protected by flockfile(stdout) */
for (i = 0; i < NUM_ITERS; i++)
{
switch (pthread_barrier_wait (&barrier))
{
case 0:
flockfile (stdout);
printf ("%04d: non-serial thread %lu\n", ++linecount,
(unsigned long) self);
funlockfile (stdout);
break;
case PTHREAD_BARRIER_SERIAL_THREAD:
flockfile (stdout);
printf ("%04d: serial thread %lu\n", ++linecount,
(unsigned long) self);
funlockfile (stdout);
last_serial_thread = self;
break;
default:
/* Huh? */
error (EXIT_FAILURE, 0, "unexpected return value from barrier wait");
}
}
if (pthread_equal (self, last_serial_thread))
{
flockfile (stdout);
printf ("%04d: last serial thread %lu terminating process\n",
++linecount, (unsigned long) self);
funlockfile (stdout);
exit (0);
}
pthread_exit(NULL);
}
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