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/* C11 threads timed mutex tests.
Copyright (C) 2018-2021 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 <threads.h>
#include <stdio.h>
#include <unistd.h>
#include <support/check.h>
/* Shared mutex between child and parent. */
static mtx_t mutex;
/* Shared counter to check possible race conditions. */
static char shrd_counter;
/* Maximum amount of time waiting for mutex. */
static struct timespec wait_time;
/* Function to choose an action to do, depending on mtx_timedlock
return value. */
static inline void
choose_action (int action, char* thread_name)
{
switch (action)
{
case thrd_success:
++shrd_counter;
if (mtx_unlock (&mutex) != thrd_success)
FAIL_EXIT1 ("mtx_unlock failed");
break;
case thrd_timedout:
break;
case thrd_error:
FAIL_EXIT1 ("%s lock error", thread_name);
break;
}
}
static int
child_add (void *arg)
{
char child_name[] = "child";
/* Try to lock mutex. */
choose_action (mtx_timedlock (&mutex, &wait_time), child_name);
thrd_exit (thrd_success);
}
static int
do_test (void)
{
thrd_t id;
char parent_name[] = "parent";
if (mtx_init (&mutex, mtx_timed) != thrd_success)
FAIL_EXIT1 ("mtx_init failed");
if (clock_gettime (CLOCK_REALTIME, &wait_time) != 0)
FAIL_EXIT1 ("clock_gettime failed");
/* Tiny amount of time, to assure that if any thread finds it busy.
It will receive thrd_timedout. */
wait_time.tv_nsec += 1;
if (wait_time.tv_nsec == 1000 * 1000 * 1000)
{
wait_time.tv_sec += 1;
wait_time.tv_nsec = 0;
}
if (thrd_create (&id, child_add, NULL) != thrd_success)
FAIL_EXIT1 ("thrd_create failed");
choose_action (mtx_timedlock (&mutex, &wait_time), parent_name);
if (thrd_join (id, NULL) != thrd_success)
FAIL_EXIT1 ("thrd_join failed");
if (shrd_counter != 2 && shrd_counter != 1)
FAIL_EXIT1 ("shrd_counter != {1,2} (%d)", shrd_counter);
mtx_destroy (&mutex);
return 0;
}
#include <support/test-driver.c>
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