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/* Test barriers.
Copyright (C) 2000-2019 Free Software Foundation, Inc.
This file is part of the GNU C Library.
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, see
<https://www.gnu.org/licenses/>. */
#define _GNU_SOURCE
#include <pthread.h>
#include <stdio.h>
#include <error.h>
#include <assert.h>
#include <errno.h>
#define THREADS 500
#define WAITS 3
void *
dowait (void *arg)
{
pthread_barrier_t *barrier = arg;
int ret;
ret = pthread_barrier_wait (barrier);
printf ("%d ", pthread_self ());
return (void *) ret;
}
int
main (int argc, char **argv)
{
pthread_barrierattr_t attr;
pthread_barrier_t barrier;
int i, j;
error_t err;
pthread_t tid[THREADS];
int havesyncs;
err = pthread_barrierattr_init (&attr);
if (err)
error (1, err, "pthread_barrierattr_init");
err = pthread_barrierattr_getpshared (&attr, &i);
if (err)
error (1, err, "pthread_barrierattr_getpshared");
assert (i == PTHREAD_PROCESS_PRIVATE || i == PTHREAD_PROCESS_SHARED);
err = pthread_barrierattr_setpshared (&attr, PTHREAD_PROCESS_PRIVATE);
if (err)
error (1, err, "pthread_barrierattr_setpshared");
err = pthread_barrier_init (&barrier, &attr, THREADS + 1);
if (err)
error (1, err, "pthread_barrier_init");
for (j = 0; j < WAITS; j++)
{
for (i = 0; i < THREADS; i++)
{
err = pthread_create (&tid[i], 0, dowait, &barrier);
if (err)
error (1, err, "pthread_create (%d)", i);
}
printf ("Manager will now call pthread_barrier_wait.\n");
havesyncs
= pthread_barrier_wait (&barrier) == PTHREAD_BARRIER_SERIAL_THREAD
? 1 : 0;
for (i = THREADS - 1; i >= 0; i--)
{
void *ret;
err = pthread_join (tid[i], &ret);
if (err)
error (1, err, "pthread_join");
switch ((int) ret)
{
case 0:
break;
case PTHREAD_BARRIER_SERIAL_THREAD:
havesyncs++;
break;
default:
assert (!"Unknown value returned from pthread_barrier_wait.");
break;
}
}
printf ("\n");
assert (havesyncs == 1);
}
return 0;
}
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