1 /* $OpenBSD: lock.h,v 1.27 2016/06/19 11:54:33 natano Exp $ */ 2 3 /* 4 * Copyright (c) 1995 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code contains ideas from software contributed to Berkeley by 8 * Avadis Tevanian, Jr., Michael Wayne Young, and the Mach Operating 9 * System project at Carnegie-Mellon University. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 * 35 * @(#)lock.h 8.12 (Berkeley) 5/19/95 36 */ 37 38 #ifndef _LOCK_H_ 39 #define _LOCK_H_ 40 41 #include <sys/rwlock.h> 42 43 #define LK_EXCLUSIVE RW_WRITE /* exclusive lock */ 44 #define LK_SHARED RW_READ /* shared lock */ 45 #define LK_TYPE_MASK (RW_WRITE|RW_READ) /* type of lock sought */ 46 #define LK_NOWAIT RW_NOSLEEP /* do not sleep to await lock */ 47 #define LK_RECURSEFAIL RW_RECURSEFAIL /* fail if recursive exclusive lock */ 48 #define LK_EXCLOTHER RW_WRITE_OTHER /* exclusive lock held by some other thread */ 49 #define LK_RWFLAGS (RW_WRITE|RW_READ|RW_NOSLEEP|RW_RECURSEFAIL|RW_WRITE_OTHER) 50 51 /* LK_ specific */ 52 #define LK_DRAIN 0x1000UL /* wait for all lock activity to end */ 53 #define LK_RETRY 0x2000UL /* vn_lock: retry until locked */ 54 55 #endif /* !_LOCK_H_ */ 56