1 /* $OpenBSD: rthread_once.c,v 1.2 2017/10/28 21:25:24 guenther Exp $ */ 2 /* 3 * Copyright (c) 2004,2005 Ted Unangst <tedu@openbsd.org> 4 * All Rights Reserved. 5 * 6 * Permission to use, copy, modify, and distribute this software for any 7 * purpose with or without fee is hereby granted, provided that the above 8 * copyright notice and this permission notice appear in all copies. 9 * 10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 14 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 15 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 16 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 17 */ 18 19 #include <pthread.h> 20 #include <stdlib.h> 21 22 static void 23 mutex_unlock(void *arg) 24 { 25 if (pthread_mutex_unlock(arg)) 26 abort(); 27 } 28 29 int 30 pthread_once(pthread_once_t *once_control, void (*init_routine)(void)) 31 { 32 pthread_mutex_lock(&once_control->mutex); 33 if (once_control->state == PTHREAD_NEEDS_INIT) { 34 pthread_cleanup_push(mutex_unlock, &once_control->mutex); 35 init_routine(); 36 pthread_cleanup_pop(0); 37 once_control->state = PTHREAD_DONE_INIT; 38 } 39 pthread_mutex_unlock(&once_control->mutex); 40 41 return (0); 42 } 43