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/* Test case for hand function calls in multi-threaded program.
Copyright 2008-2017 Free Software Foundation, Inc.
This file is part of GDB.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program 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 General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include <pthread.h>
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <unistd.h>
#ifndef NR_THREADS
#define NR_THREADS 4
#endif
int thread_count;
pthread_mutex_t thread_count_mutex;
pthread_cond_t thread_count_condvar;
void
incr_thread_count (void)
{
pthread_mutex_lock (&thread_count_mutex);
++thread_count;
if (thread_count == NR_THREADS)
pthread_cond_signal (&thread_count_condvar);
pthread_mutex_unlock (&thread_count_mutex);
}
void
cond_wait (pthread_cond_t *cond, pthread_mutex_t *mut)
{
pthread_mutex_lock (mut);
pthread_cond_wait (cond, mut);
pthread_mutex_unlock (mut);
}
void
noreturn (void)
{
pthread_mutex_t mut;
pthread_cond_t cond;
pthread_mutex_init (&mut, NULL);
pthread_cond_init (&cond, NULL);
/* Wait for a condition that will never be signaled, so we effectively
block the thread here. */
cond_wait (&cond, &mut);
}
void *
forever_pthread (void *unused)
{
incr_thread_count ();
noreturn ();
}
void
hand_call (void)
{
}
/* Wait until all threads are running. */
void
wait_all_threads_running (void)
{
pthread_mutex_lock (&thread_count_mutex);
if (thread_count == NR_THREADS)
{
pthread_mutex_unlock (&thread_count_mutex);
return;
}
pthread_cond_wait (&thread_count_condvar, &thread_count_mutex);
if (thread_count == NR_THREADS)
{
pthread_mutex_unlock (&thread_count_mutex);
return;
}
pthread_mutex_unlock (&thread_count_mutex);
printf ("failed waiting for all threads to start\n");
abort ();
}
/* Called when all threads are running.
Easy place for a breakpoint. */
void
all_threads_running (void)
{
}
int
main (void)
{
pthread_t forever[NR_THREADS];
int i;
pthread_mutex_init (&thread_count_mutex, NULL);
pthread_cond_init (&thread_count_condvar, NULL);
for (i = 0; i < NR_THREADS; ++i)
pthread_create (&forever[i], NULL, forever_pthread, NULL);
wait_all_threads_running ();
all_threads_running ();
return 0;
}
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