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/* Copyright (C) 2004-2022 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 <errno.h>
#include <limits.h>
#include <fcntl.h>
#include <pthread.h>
#include <stdbool.h>
#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
pthread_cond_t cv = PTHREAD_COND_INITIALIZER;
pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER;
bool exiting;
int fd, spins, nn;
enum { count = 8 }; /* Number of worker threads. */
void *
tf (void *id)
{
pthread_mutex_lock (&lock);
if ((long) id == 0)
{
while (!exiting)
{
if ((spins++ % 1000) == 0)
write (fd, ".", 1);
pthread_mutex_unlock (&lock);
pthread_mutex_lock (&lock);
int njobs = rand () % (count + 1);
nn = njobs;
if ((rand () % 30) == 0)
pthread_cond_broadcast (&cv);
else
while (njobs--)
pthread_cond_signal (&cv);
}
pthread_cond_broadcast (&cv);
}
else
{
while (!exiting)
{
while (!nn && !exiting)
pthread_cond_wait (&cv, &lock);
--nn;
pthread_mutex_unlock (&lock);
pthread_mutex_lock (&lock);
}
}
pthread_mutex_unlock (&lock);
return NULL;
}
int
do_test (void)
{
fd = open ("/dev/null", O_WRONLY);
if (fd < 0)
{
printf ("couldn't open /dev/null, %m\n");
return 1;
}
pthread_t th[count + 1];
pthread_attr_t attr;
int i, ret, sz;
pthread_attr_init (&attr);
sz = sysconf (_SC_PAGESIZE);
#ifdef PTHREAD_STACK_MIN
if (sz < PTHREAD_STACK_MIN)
sz = PTHREAD_STACK_MIN;
#endif
pthread_attr_setstacksize (&attr, sz);
for (i = 0; i <= count; ++i)
if ((ret = pthread_create (&th[i], &attr, tf, (void *) (long) i)) != 0)
{
errno = ret;
printf ("pthread_create %d failed: %m\n", i);
return 1;
}
struct timespec ts = { .tv_sec = 20, .tv_nsec = 0 };
while (nanosleep (&ts, &ts) != 0);
pthread_mutex_lock (&lock);
exiting = true;
pthread_mutex_unlock (&lock);
for (i = 0; i < count; ++i)
pthread_join (th[i], NULL);
close (fd);
return 0;
}
#define TEST_FUNCTION do_test ()
#define TIMEOUT 40
#include "../test-skeleton.c"
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