FreeBSD/Linux Kernel Cross Reference
sys/ufs/ufs/dir.h
1 /* $NetBSD: dir.h,v 1.17 2003/08/07 16:34:42 agc Exp $ */
2
3 /*
4 * Copyright (c) 1982, 1986, 1989, 1993
5 * The Regents of the University of California. All rights reserved.
6 * (c) UNIX System Laboratories, Inc.
7 * All or some portions of this file are derived from material licensed
8 * to the University of California by American Telephone and Telegraph
9 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
10 * the permission of UNIX System Laboratories, Inc.
11 *
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
14 * are met:
15 * 1. Redistributions of source code must retain the above copyright
16 * notice, this list of conditions and the following disclaimer.
17 * 2. Redistributions in binary form must reproduce the above copyright
18 * notice, this list of conditions and the following disclaimer in the
19 * documentation and/or other materials provided with the distribution.
20 * 3. Neither the name of the University nor the names of its contributors
21 * may be used to endorse or promote products derived from this software
22 * without specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * SUCH DAMAGE.
35 *
36 * @(#)dir.h 8.5 (Berkeley) 4/27/95
37 */
38
39 #ifndef _UFS_UFS_DIR_H_
40 #define _UFS_UFS_DIR_H_
41
42 /*
43 * Theoretically, directories can be more than 2Gb in length, however, in
44 * practice this seems unlikely. So, we define the type doff_t as a 32-bit
45 * quantity to keep down the cost of doing lookup on a 32-bit machine.
46 */
47 #define doff_t int32_t
48 #define MAXDIRSIZE (0x7fffffff)
49
50 /*
51 * A directory consists of some number of blocks of DIRBLKSIZ
52 * bytes, where DIRBLKSIZ is chosen such that it can be transferred
53 * to disk in a single atomic operation (e.g. 512 bytes on most machines).
54 *
55 * Each DIRBLKSIZ byte block contains some number of directory entry
56 * structures, which are of variable length. Each directory entry has
57 * a struct direct at the front of it, containing its inode number,
58 * the length of the entry, and the length of the name contained in
59 * the entry. These are followed by the name padded to a 4 byte boundary.
60 * All names are guaranteed null terminated.
61 * The maximum length of a name in a directory is MAXNAMLEN.
62 *
63 * The macro DIRSIZ(fmt, dp) gives the amount of space required to represent
64 * a directory entry. Free space in a directory is represented by
65 * entries which have dp->d_reclen > DIRSIZ(fmt, dp). All DIRBLKSIZ bytes
66 * in a directory block are claimed by the directory entries. This
67 * usually results in the last entry in a directory having a large
68 * dp->d_reclen. When entries are deleted from a directory, the
69 * space is returned to the previous entry in the same directory
70 * block by increasing its dp->d_reclen. If the first entry of
71 * a directory block is free, then its dp->d_ino is set to 0.
72 * Entries other than the first in a directory do not normally have
73 * dp->d_ino set to 0.
74 */
75 #undef DIRBLKSIZ
76 #define DIRBLKSIZ DEV_BSIZE
77 #undef MAXNAMLEN
78 #define MAXNAMLEN 255
79 #define APPLEUFS_DIRBLKSIZ 1024
80
81 struct direct {
82 u_int32_t d_ino; /* inode number of entry */
83 u_int16_t d_reclen; /* length of this record */
84 u_int8_t d_type; /* file type, see below */
85 u_int8_t d_namlen; /* length of string in d_name */
86 char d_name[MAXNAMLEN + 1];/* name with length <= MAXNAMLEN */
87 };
88
89 /*
90 * File types
91 */
92 #define DT_UNKNOWN 0
93 #define DT_FIFO 1
94 #define DT_CHR 2
95 #define DT_DIR 4
96 #define DT_BLK 6
97 #define DT_REG 8
98 #define DT_LNK 10
99 #define DT_SOCK 12
100 #define DT_WHT 14
101
102 /*
103 * Convert between stat structure types and directory types.
104 */
105 #define IFTODT(mode) (((mode) & 0170000) >> 12)
106 #define DTTOIF(dirtype) ((dirtype) << 12)
107
108 /*
109 * The DIRSIZ macro gives the minimum record length which will hold
110 * the directory entry. This requires the amount of space in struct direct
111 * without the d_name field, plus enough space for the name with a terminating
112 * null byte (dp->d_namlen+1), rounded up to a 4 byte boundary.
113 */
114 #define DIRECTSIZ(namlen) \
115 ((sizeof(struct direct) - (MAXNAMLEN+1)) + (((namlen)+1 + 3) &~ 3))
116
117 #if (BYTE_ORDER == LITTLE_ENDIAN)
118 #define DIRSIZ(oldfmt, dp, needswap) \
119 (((oldfmt) && !(needswap)) ? \
120 DIRECTSIZ((dp)->d_type) : DIRECTSIZ((dp)->d_namlen))
121 #else
122 #define DIRSIZ(oldfmt, dp, needswap) \
123 (((oldfmt) && (needswap)) ? \
124 DIRECTSIZ((dp)->d_type) : DIRECTSIZ((dp)->d_namlen))
125 #endif
126
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 */
134 struct dirtemplate {
135 u_int32_t dot_ino;
136 int16_t dot_reclen;
137 u_int8_t dot_type;
138 u_int8_t dot_namlen;
139 char dot_name[4]; /* must be multiple of 4 */
140 u_int32_t dotdot_ino;
141 int16_t dotdot_reclen;
142 u_int8_t dotdot_type;
143 u_int8_t dotdot_namlen;
144 char dotdot_name[4]; /* ditto */
145 };
146
147 /*
148 * This is the old format of directories, sanz type element.
149 */
150 struct odirtemplate {
151 u_int32_t dot_ino;
152 int16_t dot_reclen;
153 u_int16_t dot_namlen;
154 char dot_name[4]; /* must be multiple of 4 */
155 u_int32_t dotdot_ino;
156 int16_t dotdot_reclen;
157 u_int16_t dotdot_namlen;
158 char dotdot_name[4]; /* ditto */
159 };
160 #endif /* !_UFS_UFS_DIR_H_ */
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