diff options
Diffstat (limited to 'src/lib/rw_lock.c')
-rw-r--r-- | src/lib/rw_lock.c | 127 |
1 files changed, 0 insertions, 127 deletions
diff --git a/src/lib/rw_lock.c b/src/lib/rw_lock.c deleted file mode 100644 index ba285694..00000000 --- a/src/lib/rw_lock.c +++ /dev/null @@ -1,127 +0,0 @@ -/* - * Ouroboros - Copyright (C) 2016 - * - * Read/Write locks - * - * Dimitri Staessens <dimitri.staessens@intec.ugent.be> - * - * 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 2 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, write to the Free Software - * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. - */ - -#include <ouroboros/rw_lock.h> - -int rw_lock_init(rw_lock_t * lock) -{ - if (lock == NULL) - return -1; - - pthread_mutex_init(&lock->lock, NULL); - pthread_mutex_init(&lock->i_lock, NULL); - lock->i = 0; - - return 0; -} - -void rw_lock_destroy(rw_lock_t * lock) -{ - if (lock == NULL) - return; - - pthread_mutex_destroy(&lock->lock); - pthread_mutex_destroy(&lock->i_lock); - lock->i = -1; -} - -int rw_lock_rdlock(rw_lock_t * lock) -{ - int ret = 0; - - if (lock == NULL) - return -1; - - pthread_mutex_lock(&lock->i_lock); - - if (lock->i < 0) { - pthread_mutex_unlock(&lock->i_lock); - return -1; - } - - if (lock->i == 0) - ret = pthread_mutex_lock(&lock->lock); - - ++(lock->i); - - pthread_mutex_unlock(&lock->i_lock); - - return ret; -} - -int rw_lock_wrlock(rw_lock_t * lock) -{ - int ret = 0; - - if (lock == NULL) - return -1; - - pthread_mutex_lock(&lock->i_lock); - - if (lock->i < 0) { - pthread_mutex_unlock(&lock->i_lock); - return -1; - } - - pthread_mutex_unlock(&lock->i_lock); - - while (1) { - pthread_mutex_lock(&lock->i_lock); - - if (lock->i == 0) { - ++(lock->i); - ret = pthread_mutex_lock(&lock->lock); - pthread_mutex_unlock(&lock->i_lock); - break; - } - - pthread_mutex_unlock(&lock->i_lock); - - sched_yield(); - } - - return ret; -} - -int rw_lock_unlock(rw_lock_t * lock) -{ - int ret = 0; - - if (lock == NULL) - return -1; - - pthread_mutex_lock(&lock->i_lock); - - if (lock->i < 0) { - pthread_mutex_unlock(&lock->i_lock); - return -1; - } - - --(lock->i); - - if (lock->i == 0) - ret = pthread_mutex_unlock(&lock->lock); - - pthread_mutex_unlock(&lock->i_lock); - - return ret; -} |