1 /* 2 * Copyright (C) 2008 The Android Open Source Project 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * * Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * * Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in 12 * the documentation and/or other materials provided with the 13 * distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 16 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 17 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 18 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 19 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 22 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 25 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 #ifndef _SEMAPHORE_H 29 #define _SEMAPHORE_H 30 31 #include <sys/cdefs.h> 32 33 __BEGIN_DECLS 34 35 typedef struct { 36 volatile unsigned int count; 37 } sem_t; 38 39 #define SEM_FAILED NULL 40 41 extern int sem_init(sem_t *sem, int pshared, unsigned int value); 42 43 extern int sem_close(sem_t *); 44 extern int sem_destroy(sem_t *); 45 extern int sem_getvalue(sem_t *, int *); 46 extern int sem_init(sem_t *, int, unsigned int); 47 extern sem_t *sem_open(const char *, int, ...); 48 extern int sem_post(sem_t *); 49 extern int sem_trywait(sem_t *); 50 extern int sem_unlink(const char *); 51 extern int sem_wait(sem_t *); 52 53 struct timespec; 54 extern int sem_timedwait(sem_t *sem, const struct timespec *abs_timeout); 55 56 __END_DECLS 57 58 #endif /* _SEMAPHORE_H */ 59