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/* Test for Pthreads/mutexes.
Copyright (C) 2000, 2001, 2002 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Kurt Garloff <garloff@suse.de>, 2000.
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; 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 <pthread.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
static void *thread_start (void *ptr) __attribute__ ((__noreturn__));
struct thr_ctrl
{
pthread_mutex_t mutex;
pthread_cond_t cond;
int retval;
};
static void
dump_mut (pthread_mutex_t * mut)
{
size_t i;
for (i = 0; i < sizeof (*mut); i++)
printf (" %02x", *((unsigned char *) mut + i));
printf ("\n");
};
/* Helper, the opposite of pthread_cond_wait (cond, mut). */
static void
pthr_cond_signal_mutex (pthread_cond_t * cond, pthread_mutex_t * mut)
{
int err;
err = pthread_mutex_lock (mut);
if (err)
printf ("mutex_lock : %s\n", strerror (err));
err = pthread_cond_signal (cond);
if (err)
printf ("cond_signal : %s\n", strerror (err));
err = pthread_mutex_unlock (mut);
if (err)
printf ("mutex_unlock: %s\n", strerror (err));
}
static void *
thread_start (void *ptr)
{
struct thr_ctrl *tc = ptr;
/* Do initialization. */
/* ... */
/* Signal that we are ready. */
pthr_cond_signal_mutex (&tc->cond, &tc->mutex);
sleep (2);
pthr_cond_signal_mutex (&tc->cond, &tc->mutex);
tc->retval = 0;
pthread_exit (&tc->retval);
}
int
main (void)
{
struct thr_ctrl threadctrl;
pthread_t thread;
int err;
int *res = &threadctrl.retval;
pthread_mutexattr_t mutattr;
pthread_mutexattr_init (&mutattr);
pthread_mutex_init (&threadctrl.mutex, &mutattr);
pthread_cond_init (&threadctrl.cond, NULL);
err = pthread_mutex_lock (&threadctrl.mutex);
if (err)
printf ("mutex_lock : %s\n", strerror (err));
dump_mut (&threadctrl.mutex);
pthread_create (&thread, NULL, thread_start, &threadctrl);
/* Wait until it's ready. */
err = pthread_cond_wait (&threadctrl.cond, &threadctrl.mutex);
if (err)
printf ("cond_wait : %s\n", strerror (err));
/* Now, we should have acquired the mutex again! */
dump_mut (&threadctrl.mutex);
sleep (1);
dump_mut (&threadctrl.mutex);
err = pthread_cond_wait (&threadctrl.cond, &threadctrl.mutex);
if (err)
{
printf ("cond_wait : %s\n", strerror (err));
printf ("ERROR\n");
abort ();
};
dump_mut (&threadctrl.mutex);
pthread_join (thread, (void **) &res);
printf ("OK\n");
return 0;
}
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