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/* Copyright (C) 2004-2021 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Jakub Jelinek <jakub@redhat.com>, 2004.
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 <pthread.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#define N 10
#define ROUNDS 1000
static pthread_cond_t cond = PTHREAD_COND_INITIALIZER;
static pthread_cond_t cond2 = PTHREAD_COND_INITIALIZER;
static pthread_mutex_t mut = PTHREAD_MUTEX_INITIALIZER;
static pthread_barrier_t b;
static int count;
static void *
tf (void *p)
{
int i;
for (i = 0; i < ROUNDS; ++i)
{
pthread_mutex_lock (&mut);
if (++count == N)
pthread_cond_signal (&cond2);
#ifdef TIMED
struct timeval tv;
gettimeofday (&tv, NULL);
struct timespec ts;
/* Wait three seconds. */
ts.tv_sec = tv.tv_sec + 3;
ts.tv_nsec = tv.tv_usec * 1000;
pthread_cond_timedwait (&cond, &mut, &ts);
#else
pthread_cond_wait (&cond, &mut);
#endif
pthread_mutex_unlock (&mut);
int err = pthread_barrier_wait (&b);
if (err != 0 && err != PTHREAD_BARRIER_SERIAL_THREAD)
{
puts ("child: barrier_wait failed");
exit (1);
}
err = pthread_barrier_wait (&b);
if (err != 0 && err != PTHREAD_BARRIER_SERIAL_THREAD)
{
puts ("child: barrier_wait failed");
exit (1);
}
}
return NULL;
}
static int
do_test (void)
{
if (pthread_barrier_init (&b, NULL, N + 1) != 0)
{
puts ("barrier_init failed");
return 1;
}
pthread_mutex_lock (&mut);
int i, j, err;
pthread_t th[N];
for (i = 0; i < N; ++i)
if ((err = pthread_create (&th[i], NULL, tf, NULL)) != 0)
{
printf ("cannot create thread %d: %s\n", i, strerror (err));
return 1;
}
for (i = 0; i < ROUNDS; ++i)
{
/* Make sure we discard spurious wake-ups. */
do
pthread_cond_wait (&cond2, &mut);
while (count != N);
if (i & 1)
pthread_mutex_unlock (&mut);
if (i & 2)
pthread_cond_broadcast (&cond);
else if (i & 4)
for (j = 0; j < N; ++j)
pthread_cond_signal (&cond);
else
{
for (j = 0; j < (i / 8) % N; ++j)
pthread_cond_signal (&cond);
pthread_cond_broadcast (&cond);
}
if ((i & 1) == 0)
pthread_mutex_unlock (&mut);
err = pthread_cond_destroy (&cond);
if (err)
{
printf ("pthread_cond_destroy failed: %s\n", strerror (err));
return 1;
}
/* Now clobber the cond variable which has been successfully
destroyed above. */
memset (&cond, (char) i, sizeof (cond));
err = pthread_barrier_wait (&b);
if (err != 0 && err != PTHREAD_BARRIER_SERIAL_THREAD)
{
puts ("parent: barrier_wait failed");
return 1;
}
pthread_mutex_lock (&mut);
err = pthread_barrier_wait (&b);
if (err != 0 && err != PTHREAD_BARRIER_SERIAL_THREAD)
{
puts ("parent: barrier_wait failed");
return 1;
}
count = 0;
err = pthread_cond_init (&cond, NULL);
if (err)
{
printf ("pthread_cond_init failed: %s\n", strerror (err));
return 1;
}
}
for (i = 0; i < N; ++i)
if ((err = pthread_join (th[i], NULL)) != 0)
{
printf ("failed to join thread %d: %s\n", i, strerror (err));
return 1;
}
puts ("done");
return 0;
}
#define TEST_FUNCTION do_test ()
#include "../test-skeleton.c"
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