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/* Copyright (C) 2002-2025 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/>. */
#include <error.h>
#include <pthread.h>
#include <stdio.h>
#include <stdlib.h>
static pthread_mutex_t mut = PTHREAD_MUTEX_INITIALIZER;
static pthread_cond_t cond = PTHREAD_COND_INITIALIZER;
static pthread_barrier_t bar;
static void *
tf (void *a)
{
int i = (long int) a;
int err;
printf ("child %d: lock\n", i);
err = pthread_mutex_lock (&mut);
if (err != 0)
error (EXIT_FAILURE, err, "locking in child failed");
printf ("child %d: sync\n", i);
int e = pthread_barrier_wait (&bar);
if (e != 0 && e != PTHREAD_BARRIER_SERIAL_THREAD)
{
puts ("child: barrier_wait failed");
exit (1);
}
printf ("child %d: wait\n", i);
err = pthread_cond_wait (&cond, &mut);
if (err != 0)
error (EXIT_FAILURE, err, "child %d: failed to wait", i);
printf ("child %d: woken up\n", i);
err = pthread_mutex_unlock (&mut);
if (err != 0)
error (EXIT_FAILURE, err, "child %d: unlock[2] failed", i);
printf ("child %d: done\n", i);
return NULL;
}
#define N 10
static int
do_test (void)
{
pthread_t th[N];
int i;
int err;
printf ("&cond = %p\n&mut = %p\n", &cond, &mut);
if (pthread_barrier_init (&bar, NULL, 2) != 0)
{
puts ("barrier_init failed");
exit (1);
}
pthread_attr_t at;
if (pthread_attr_init (&at) != 0)
{
puts ("attr_init failed");
return 1;
}
if (pthread_attr_setstacksize (&at, 1 * 1024 * 1024) != 0)
{
puts ("attr_setstacksize failed");
return 1;
}
for (i = 0; i < N; ++i)
{
printf ("create thread %d\n", i);
err = pthread_create (&th[i], &at, tf, (void *) (long int) i);
if (err != 0)
error (EXIT_FAILURE, err, "cannot create thread %d", i);
printf ("wait for child %d\n", i);
/* Wait for the child to start up and get the mutex for the
conditional variable. */
int e = pthread_barrier_wait (&bar);
if (e != 0 && e != PTHREAD_BARRIER_SERIAL_THREAD)
{
puts ("barrier_wait failed");
exit (1);
}
}
if (pthread_attr_destroy (&at) != 0)
{
puts ("attr_destroy failed");
return 1;
}
puts ("get lock ourselves");
err = pthread_mutex_lock (&mut);
if (err != 0)
error (EXIT_FAILURE, err, "mut locking failed");
puts ("broadcast");
/* Wake up all threads. */
err = pthread_cond_broadcast (&cond);
if (err != 0)
error (EXIT_FAILURE, err, "parent: broadcast failed");
err = pthread_mutex_unlock (&mut);
if (err != 0)
error (EXIT_FAILURE, err, "mut unlocking failed");
/* Join all threads. */
for (i = 0; i < N; ++i)
{
printf ("join thread %d\n", i);
err = pthread_join (th[i], NULL);
if (err != 0)
error (EXIT_FAILURE, err, "join of child %d failed", i);
}
puts ("done");
return 0;
}
#define TEST_FUNCTION do_test ()
#include "../test-skeleton.c"
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