ext2fs_dir.h revision 1.17 1 /* $NetBSD: ext2fs_dir.h,v 1.17 2009/09/12 14:59:59 tsutsui 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 8.4 (Berkeley) 8/10/94
37 * Modified for ext2fs by Manuel Bouyer.
38 */
39
40 /*
41 * Copyright (c) 1997 Manuel Bouyer.
42 *
43 * Redistribution and use in source and binary forms, with or without
44 * modification, are permitted provided that the following conditions
45 * are met:
46 * 1. Redistributions of source code must retain the above copyright
47 * notice, this list of conditions and the following disclaimer.
48 * 2. Redistributions in binary form must reproduce the above copyright
49 * notice, this list of conditions and the following disclaimer in the
50 * documentation and/or other materials provided with the distribution.
51 * 3. All advertising materials mentioning features or use of this software
52 * must display the following acknowledgement:
53 * This product includes software developed by Manuel Bouyer.
54 * 4. The name of the author may not be used to endorse or promote products
55 * derived from this software without specific prior written permission.
56 *
57 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
58 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
59 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
60 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
61 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
62 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
63 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
64 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
65 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
66 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
67 *
68 * @(#)dir.h 8.4 (Berkeley) 8/10/94
69 * Modified for ext2fs by Manuel Bouyer.
70 */
71
72 #ifndef _UFS_EXT2FS_EXT2FS_DIR_H_
73 #define _UFS_EXT2FS_EXT2FS_DIR_H_
74
75 /*
76 * Theoretically, directories can be more than 2Gb in length, however, in
77 * practice this seems unlikely. So, we define the type doff_t as a 32-bit
78 * quantity to keep down the cost of doing lookup on a 32-bit machine.
79 */
80 #define doff_t int32_t
81 #define EXT2FS_MAXDIRSIZE INT32_MAX
82
83 /*
84 * A directory consists of some number of blocks of e2fs_bsize bytes.
85 *
86 * Each block contains some number of directory entry
87 * structures, which are of variable length. Each directory entry has
88 * a struct direct at the front of it, containing its inode number,
89 * the length of the entry, and the length of the name contained in
90 * the entry. These are followed by the name padded to a 4 byte boundary
91 * with null bytes. All names are guaranteed null terminated.
92 * The maximum length of a name in a directory is EXT2FS_MAXNAMLEN.
93 *
94 * The macro EXT2FS_DIRSIZ(fmt, dp) gives the amount of space required to
95 * represent a directory entry. Free space in a directory is represented by
96 * entries which have dp->e2d_reclen > DIRSIZ(fmt, dp). All d2fs_bsize bytes
97 * in a directory block are claimed by the directory entries. This
98 * usually results in the last entry in a directory having a large
99 * dp->e2d_reclen. When entries are deleted from a directory, the
100 * space is returned to the previous entry in the same directory
101 * block by increasing its dp->e2d_reclen. If the first entry of
102 * a directory block is free, then its dp->e2d_ino is set to 0.
103 * Entries other than the first in a directory do not normally have
104 * dp->e2d_ino set to 0.
105 * Ext2 rev 0 has a 16 bits e2d_namlen. For Ext2 vev 1 this has been split
106 * into a 8 bits e2d_namlen and 8 bits e2d_type (looks like ffs, isnt't it ? :)
107 * It's safe to use this for rev 0 as well because all ext2 are little-endian.
108 */
109
110 #define EXT2FS_MAXNAMLEN 255
111
112 struct ext2fs_direct {
113 uint32_t e2d_ino; /* inode number of entry */
114 uint16_t e2d_reclen; /* length of this record */
115 uint8_t e2d_namlen; /* length of string in d_name */
116 uint8_t e2d_type; /* file type */
117 char e2d_name[EXT2FS_MAXNAMLEN];/* name with length<=EXT2FS_MAXNAMLEN */
118 };
119
120 /* Ext2 directory file types (not the same as FFS. Sigh.) */
121 #define EXT2_FT_UNKNOWN 0
122 #define EXT2_FT_REG_FILE 1
123 #define EXT2_FT_DIR 2
124 #define EXT2_FT_CHRDEV 3
125 #define EXT2_FT_BLKDEV 4
126 #define EXT2_FT_FIFO 5
127 #define EXT2_FT_SOCK 6
128 #define EXT2_FT_SYMLINK 7
129
130 #define EXT2_FT_MAX 8
131
132 #define E2IFTODT(mode) (((mode) & 0170000) >> 12)
133
134 static __inline uint8_t inot2ext2dt(uint16_t) __unused;
135 static __inline uint8_t
136 inot2ext2dt(uint16_t type)
137 {
138
139 switch (type) {
140 case E2IFTODT(EXT2_IFIFO):
141 return EXT2_FT_FIFO;
142 case E2IFTODT(EXT2_IFCHR):
143 return EXT2_FT_CHRDEV;
144 case E2IFTODT(EXT2_IFDIR):
145 return EXT2_FT_DIR;
146 case E2IFTODT(EXT2_IFBLK):
147 return EXT2_FT_BLKDEV;
148 case E2IFTODT(EXT2_IFREG):
149 return EXT2_FT_REG_FILE;
150 case E2IFTODT(EXT2_IFLNK):
151 return EXT2_FT_SYMLINK;
152 case E2IFTODT(EXT2_IFSOCK):
153 return EXT2_FT_SOCK;
154 default:
155 return 0;
156 }
157 }
158
159 /*
160 * The EXT2FS_DIRSIZ macro gives the minimum record length which will hold
161 * the directory entryfor a name len "len" (without the terminating null byte).
162 * This requires the amount of space in struct direct
163 * without the d_name field, plus enough space for the name without a
164 * terminating null byte, rounded up to a 4 byte boundary.
165 */
166 #define EXT2FS_DIRSIZ(len) roundup2(8 + len, 4)
167
168 /*
169 * Template for manipulating directories. Should use struct direct's,
170 * but the name field is EXT2FS_MAXNAMLEN - 1, and this just won't do.
171 */
172 struct ext2fs_dirtemplate {
173 uint32_t dot_ino;
174 int16_t dot_reclen;
175 uint8_t dot_namlen;
176 uint8_t dot_type;
177 char dot_name[4]; /* must be multiple of 4 */
178 uint32_t dotdot_ino;
179 int16_t dotdot_reclen;
180 uint8_t dotdot_namlen;
181 uint8_t dotdot_type;
182 char dotdot_name[4]; /* ditto */
183 };
184
185 #endif /* !_UFS_EXT2FS_EXT2FS_DIR_H_ */
186