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- /* Copyright (C) 2005-2022 Free Software Foundation, Inc.
- Contributed by Richard Henderson <rth@redhat.com>.
- This file is part of the GNU Offloading and Multi Processing Library
- (libgomp).
- Libgomp 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, or (at your option)
- any later version.
- Libgomp 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.
- Under Section 7 of GPL version 3, you are granted additional
- permissions described in the GCC Runtime Library Exception, version
- 3.1, as published by the Free Software Foundation.
- You should have received a copy of the GNU General Public License and
- a copy of the GCC Runtime Library Exception along with this program;
- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
- <http://www.gnu.org/licenses/>. */
- /* This is the default POSIX 1003.1b implementation of a semaphore
- synchronization mechanism for libgomp. This type is private to
- the library.
- This is a bit heavy weight for what we need, in that we're not
- interested in sem_wait as a cancelation point, but it's not too
- bad for a default. */
- #include "libgomp.h"
- #ifdef HAVE_BROKEN_POSIX_SEMAPHORES
- #include <stdlib.h>
- void gomp_sem_init (gomp_sem_t *sem, int value)
- {
- int ret;
- ret = pthread_mutex_init (&sem->mutex, NULL);
- if (ret)
- return;
- ret = pthread_cond_init (&sem->cond, NULL);
- if (ret)
- return;
- sem->value = value;
- }
- void gomp_sem_wait (gomp_sem_t *sem)
- {
- int ret;
- ret = pthread_mutex_lock (&sem->mutex);
- if (ret)
- return;
- if (sem->value > 0)
- {
- sem->value--;
- ret = pthread_mutex_unlock (&sem->mutex);
- return;
- }
- while (sem->value <= 0)
- {
- ret = pthread_cond_wait (&sem->cond, &sem->mutex);
- if (ret)
- {
- pthread_mutex_unlock (&sem->mutex);
- return;
- }
- }
- sem->value--;
- ret = pthread_mutex_unlock (&sem->mutex);
- return;
- }
- void gomp_sem_post (gomp_sem_t *sem)
- {
- int ret;
- ret = pthread_mutex_lock (&sem->mutex);
- if (ret)
- return;
- sem->value++;
- ret = pthread_mutex_unlock (&sem->mutex);
- if (ret)
- return;
- ret = pthread_cond_signal (&sem->cond);
- return;
- }
- void gomp_sem_destroy (gomp_sem_t *sem)
- {
- int ret;
- ret = pthread_mutex_destroy (&sem->mutex);
- if (ret)
- return;
- ret = pthread_cond_destroy (&sem->cond);
- return;
- }
- int gomp_sem_getcount (gomp_sem_t *sem)
- {
- int ret, count;
- ret = pthread_mutex_lock (&sem->mutex);
- if (ret)
- return -1;
- count = sem->value;
- ret = pthread_mutex_unlock (&sem->mutex);
- if (ret)
- return -1;
- if (count < 0)
- return -1;
- return count;
- }
- #else /* HAVE_BROKEN_POSIX_SEMAPHORES */
- void
- gomp_sem_wait (gomp_sem_t *sem)
- {
- /* With POSIX, the wait can be canceled by signals. We don't want that.
- It is expected that the return value here is -1 and errno is EINTR. */
- while (sem_wait (sem) != 0)
- continue;
- }
- #endif
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