kernel/ufs: Use __offsetof() instead of offsetof() (unbreaks buildworld).
[dragonfly.git] / sys / vfs / ufs / dir.h
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f719c866 1/*-
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2 * Copyright (c) 1982, 1986, 1989, 1993
3 * The Regents of the University of California. All rights reserved.
4 * (c) UNIX System Laboratories, Inc.
5 * All or some portions of this file are derived from material licensed
6 * to the University of California by American Telephone and Telegraph
7 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
8 * the permission of UNIX System Laboratories, Inc.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. All advertising materials mentioning features or use of this software
19 * must display the following acknowledgement:
20 * This product includes software developed by the University of
21 * California, Berkeley and its contributors.
22 * 4. Neither the name of the University nor the names of its contributors
23 * may be used to endorse or promote products derived from this software
24 * without specific prior written permission.
25 *
26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 * SUCH DAMAGE.
37 *
38 * @(#)dir.h 8.2 (Berkeley) 1/21/94
39 * $FreeBSD: src/sys/ufs/ufs/dir.h,v 1.9 1999/08/28 00:52:27 peter Exp $
50e58362 40 * $DragonFly: src/sys/vfs/ufs/dir.h,v 1.4 2006/04/03 02:02:37 dillon Exp $
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41 */
42
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43#ifndef _VFS_UFS_DIR_H_
44#define _VFS_UFS_DIR_H_
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45
46/*
47 * Theoretically, directories can be more than 2Gb in length, however, in
48 * practice this seems unlikely. So, we define the type doff_t as a 32-bit
49 * quantity to keep down the cost of doing lookup on a 32-bit machine.
50 */
51#define doff_t int32_t
52#define MAXDIRSIZE (0x7fffffff)
53
54/*
55 * A directory consists of some number of blocks of DIRBLKSIZ
56 * bytes, where DIRBLKSIZ is chosen such that it can be transferred
57 * to disk in a single atomic operation (e.g. 512 bytes on most machines).
58 *
59 * Each DIRBLKSIZ byte block contains some number of directory entry
60 * structures, which are of variable length. Each directory entry has
61 * a struct direct at the front of it, containing its inode number,
62 * the length of the entry, and the length of the name contained in
63 * the entry. These are followed by the name padded to a 4 byte boundary
64 * with null bytes. All names are guaranteed null terminated.
65 * The maximum length of a name in a directory is MAXNAMLEN.
66 *
67 * The macro DIRSIZ(fmt, dp) gives the amount of space required to represent
68 * a directory entry. Free space in a directory is represented by
69 * entries which have dp->d_reclen > DIRSIZ(fmt, dp). All DIRBLKSIZ bytes
70 * in a directory block are claimed by the directory entries. This
71 * usually results in the last entry in a directory having a large
72 * dp->d_reclen. When entries are deleted from a directory, the
73 * space is returned to the previous entry in the same directory
74 * block by increasing its dp->d_reclen. If the first entry of
75 * a directory block is free, then its dp->d_ino is set to 0.
76 * Entries other than the first in a directory do not normally have
77 * dp->d_ino set to 0.
78 */
79#define DIRBLKSIZ DEV_BSIZE
80#define MAXNAMLEN 255
81
82struct direct {
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83 uint32_t d_ino; /* inode number of entry */
84 uint16_t d_reclen; /* length of this record */
85 uint8_t d_type; /* file type, see below */
86 uint8_t d_namlen; /* length of string in d_name */
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87 char d_name[MAXNAMLEN + 1];/* name with length <= MAXNAMLEN */
88};
89
90/*
91 * File types
92 */
93#define DT_UNKNOWN 0
94#define DT_FIFO 1
95#define DT_CHR 2
96#define DT_DIR 4
97#define DT_BLK 6
98#define DT_REG 8
99#define DT_LNK 10
100#define DT_SOCK 12
101#define DT_WHT 14
102
103/*
104 * Convert between stat structure types and directory types.
105 */
106#define IFTODT(mode) (((mode) & 0170000) >> 12)
107#define DTTOIF(dirtype) ((dirtype) << 12)
108
109/*
110 * The DIRSIZ macro gives the minimum record length which will hold
111 * the directory entry. This requires the amount of space in struct direct
112 * without the d_name field, plus enough space for the name with a terminating
113 * null byte (dp->d_namlen+1), rounded up to a 4 byte boundary.
114 *
115 *
116 */
117#define DIRECTSIZ(namlen) \
4c33c46d 118 ((__offsetof(struct direct, d_name) + \
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119 ((namlen)+1)*sizeof(((struct direct *)0)->d_name[0]) + 3) & ~3)
120#if (BYTE_ORDER == LITTLE_ENDIAN)
121#define DIRSIZ(oldfmt, dp) \
122 ((oldfmt) ? DIRECTSIZ((dp)->d_type) : DIRECTSIZ((dp)->d_namlen))
123#else
124#define DIRSIZ(oldfmt, dp) \
125 DIRECTSIZ((dp)->d_namlen)
126#endif
127#define OLDDIRFMT 1
128#define NEWDIRFMT 0
129
130/*
131 * Template for manipulating directories. Should use struct direct's,
132 * but the name field is MAXNAMLEN - 1, and this just won't do.
133 */
134struct dirtemplate {
f719c866 135 uint32_t dot_ino;
984263bc 136 int16_t dot_reclen;
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137 uint8_t dot_type;
138 uint8_t dot_namlen;
984263bc 139 char dot_name[4]; /* must be multiple of 4 */
f719c866 140 uint32_t dotdot_ino;
984263bc 141 int16_t dotdot_reclen;
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142 uint8_t dotdot_type;
143 uint8_t dotdot_namlen;
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144 char dotdot_name[4]; /* ditto */
145};
146
147/*
148 * This is the old format of directories, sanz type element.
149 */
150struct odirtemplate {
f719c866 151 uint32_t dot_ino;
984263bc 152 int16_t dot_reclen;
f719c866 153 uint16_t dot_namlen;
984263bc 154 char dot_name[4]; /* must be multiple of 4 */
f719c866 155 uint32_t dotdot_ino;
984263bc 156 int16_t dotdot_reclen;
f719c866 157 uint16_t dotdot_namlen;
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158 char dotdot_name[4]; /* ditto */
159};
50e58362 160#endif /* !_VFS_UFS_DIR_H_ */