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1/*
2 * Copyright (c) 2000-2002 Apple Computer, Inc. All rights reserved.
3 *
4 * @APPLE_LICENSE_HEADER_START@
5 *
6 * The contents of this file constitute Original Code as defined in and
7 * are subject to the Apple Public Source License Version 1.1 (the
8 * "License"). You may not use this file except in compliance with the
9 * License. Please obtain a copy of the License at
10 * http://www.apple.com/publicsource and read it before using this file.
11 *
12 * This Original Code and all software distributed under the License are
13 * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
14 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
15 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
16 * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the
17 * License for the specific language governing rights and limitations
18 * under the License.
19 *
20 * @APPLE_LICENSE_HEADER_END@
21 */
22/* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */
23/*
24 * Copyright (c) 1991, 1993
25 * The Regents of the University of California. All rights reserved.
26 *
27 * This code is derived from software contributed to Berkeley by
28 * Scooter Morris at Genentech Inc.
29 *
30 * Redistribution and use in source and binary forms, with or without
31 * modification, are permitted provided that the following conditions
32 * are met:
33 * 1. Redistributions of source code must retain the above copyright
34 * notice, this list of conditions and the following disclaimer.
35 * 2. Redistributions in binary form must reproduce the above copyright
36 * notice, this list of conditions and the following disclaimer in the
37 * documentation and/or other materials provided with the distribution.
38 * 3. All advertising materials mentioning features or use of this software
39 * must display the following acknowledgement:
40 * This product includes software developed by the University of
41 * California, Berkeley and its contributors.
42 * 4. Neither the name of the University nor the names of its contributors
43 * may be used to endorse or promote products derived from this software
44 * without specific prior written permission.
45 *
46 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
47 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
48 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
49 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
50 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
51 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
52 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
53 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
54 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
55 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
56 * SUCH DAMAGE.
57 *
58 * @(#)lockf.h 8.2 (Berkeley) 10/26/94
59 */
60#ifndef _UFS_LOCKF_H_
61#define _UFS_LOCKF_H_
62
63#include <sys/appleapiopts.h>
64
65#ifdef __APPLE_API_PRIVATE
66/*
67 * The lockf structure is a kernel structure which contains the information
68 * associated with a byte range lock. The lockf structures are linked into
69 * the specinfo structure. Locks are sorted by the starting byte of the lock for
70 * efficiency.
71 */
72TAILQ_HEAD(locklist, lockf);
73
74struct specinfo;
75struct lockf {
76 short lf_flags; /* Semantics: F_POSIX, F_FLOCK, F_WAIT */
77 short lf_type; /* Lock type: F_RDLCK, F_WRLCK */
78 off_t lf_start; /* Byte # of the start of the lock */
79 off_t lf_end; /* Byte # of the end of the lock (-1=EOF) */
80 caddr_t lf_id; /* Id of the resource holding the lock */
81 struct specinfo *lf_specinfo; /* Back pointer to the specinfo */
82 struct lockf *lf_next; /* Pointer to the next lock on this info */
83 struct locklist lf_blkhd; /* List of requests blocked on this lock */
84 TAILQ_ENTRY(lockf) lf_block;/* A request waiting for a lock */
85};
86
87/* Maximum length of sleep chains to traverse to try and detect deadlock. */
88#define MAXDEPTH 50
89
90__BEGIN_DECLS
91void spec_lf_addblock __P((struct lockf *, struct lockf *));
92int spec_lf_clearlock __P((struct lockf *));
93int spec_lf_findoverlap __P((struct lockf *,
94 struct lockf *, int, struct lockf ***, struct lockf **));
95struct lockf *
96 spec_lf_getblock __P((struct lockf *));
97int spec_lf_getlock __P((struct lockf *, struct flock *));
98int spec_lf_setlock __P((struct lockf *));
99void spec_lf_split __P((struct lockf *, struct lockf *));
100void spec_lf_wakelock __P((struct lockf *));
101__END_DECLS
102
103#ifdef LOCKF_DEBUG
104extern int lockf_debug;
105
106__BEGIN_DECLS
107void spec_lf_print __P((char *, struct lockf *));
108void spec_lf_printlist __P((char *, struct lockf *));
109__END_DECLS
110#endif
111
112#endif /* __APPLE_API_PRIVATE */
113#endif /* ! _UFS_LOCKF_H_ */
114