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/* Test program for timedout read/write lock functions.
Copyright (C) 2000-2021 Free Software Foundation, Inc.
Contributed by Ulrich Drepper <drepper@redhat.com>, 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, see <https://www.gnu.org/licenses/>. */
#include <errno.h>
#include <error.h>
#include <pthread.h>
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <unistd.h>
#define NWRITERS 15
#define WRITETRIES 10
#define NREADERS 15
#define READTRIES 15
#define DELAY 1000000
#ifndef KIND
# define KIND PTHREAD_RWLOCK_PREFER_WRITER_NONRECURSIVE_NP
#endif
static pthread_rwlock_t lock;
static void *
writer_thread (void *nr)
{
struct timespec delay;
int n;
delay.tv_sec = 0;
delay.tv_nsec = DELAY;
for (n = 0; n < WRITETRIES; ++n)
{
printf ("writer thread %ld tries again\n", (long int) nr);
if (pthread_rwlock_wrlock (&lock) != 0)
{
puts ("wrlock failed");
exit (1);
}
printf ("writer thread %ld succeeded\n", (long int) nr);
nanosleep (&delay, NULL);
if (pthread_rwlock_unlock (&lock) != 0)
{
puts ("unlock for writer failed");
exit (1);
}
printf ("writer thread %ld released\n", (long int) nr);
}
return NULL;
}
static void *
reader_thread (void *nr)
{
struct timespec delay;
int n;
delay.tv_sec = 0;
delay.tv_nsec = DELAY;
for (n = 0; n < READTRIES; ++n)
{
printf ("reader thread %ld tries again\n", (long int) nr);
if (pthread_rwlock_rdlock (&lock) != 0)
{
puts ("rdlock failed");
exit (1);
}
printf ("reader thread %ld succeeded\n", (long int) nr);
nanosleep (&delay, NULL);
if (pthread_rwlock_unlock (&lock) != 0)
{
puts ("unlock for reader failed");
exit (1);
}
printf ("reader thread %ld released\n", (long int) nr);
}
return NULL;
}
static int
do_test (void)
{
pthread_t thwr[NWRITERS];
pthread_t thrd[NREADERS];
int n;
void *res;
pthread_rwlockattr_t a;
if (pthread_rwlockattr_init (&a) != 0)
{
puts ("rwlockattr_t failed");
exit (1);
}
if (pthread_rwlockattr_setkind_np (&a, KIND) != 0)
{
puts ("rwlockattr_setkind failed");
exit (1);
}
if (pthread_rwlock_init (&lock, &a) != 0)
{
puts ("rwlock_init failed");
exit (1);
}
/* Make standard error the same as standard output. */
dup2 (1, 2);
/* Make sure we see all message, even those on stdout. */
setvbuf (stdout, NULL, _IONBF, 0);
for (n = 0; n < NWRITERS; ++n)
if (pthread_create (&thwr[n], NULL, writer_thread,
(void *) (long int) n) != 0)
{
puts ("writer create failed");
exit (1);
}
for (n = 0; n < NREADERS; ++n)
if (pthread_create (&thrd[n], NULL, reader_thread,
(void *) (long int) n) != 0)
{
puts ("reader create failed");
exit (1);
}
/* Wait for all the threads. */
for (n = 0; n < NWRITERS; ++n)
if (pthread_join (thwr[n], &res) != 0)
{
puts ("writer join failed");
exit (1);
}
for (n = 0; n < NREADERS; ++n)
if (pthread_join (thrd[n], &res) != 0)
{
puts ("reader join failed");
exit (1);
}
return 0;
}
#define TIMEOUT 30
#define TEST_FUNCTION do_test ()
#include "../test-skeleton.c"
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