1 /* $NetBSD: ext2fs_dir.h,v 1.19 2012/05/09 00:21:18 riastradh 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 *
52 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
53 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
54 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
55 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
56 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
57 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
58 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
59 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
60 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
61 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
62 *
63 * @(#)dir.h 8.4 (Berkeley) 8/10/94
64 * Modified for ext2fs by Manuel Bouyer.
65 */
66
67 #ifndef _UFS_EXT2FS_EXT2FS_DIR_H_
68 #define _UFS_EXT2FS_EXT2FS_DIR_H_
69
70 #include <ufs/ext2fs/ext2fs_dinode.h>
71
72 /*
73 * Theoretically, directories can be more than 2Gb in length, however, in
74 * practice this seems unlikely. So, we define the type doff_t as a 32-bit
75 * quantity to keep down the cost of doing lookup on a 32-bit machine.
76 */
77 #define doff_t int32_t
78 #define EXT2FS_MAXDIRSIZE INT32_MAX
79
80 /*
81 * A directory consists of some number of blocks of e2fs_bsize bytes.
82 *
83 * Each block contains some number of directory entry
84 * structures, which are of variable length. Each directory entry has
85 * a struct direct at the front of it, containing its inode number,
86 * the length of the entry, and the length of the name contained in
87 * the entry. These are followed by the name padded to a 4 byte boundary
88 * with null bytes. All names are guaranteed null terminated.
89 * The maximum length of a name in a directory is EXT2FS_MAXNAMLEN.
90 *
91 * The macro EXT2FS_DIRSIZ(fmt, dp) gives the amount of space required to
92 * represent a directory entry. Free space in a directory is represented by
93 * entries which have dp->e2d_reclen > DIRSIZ(fmt, dp). All d2fs_bsize bytes
94 * in a directory block are claimed by the directory entries. This
95 * usually results in the last entry in a directory having a large
96 * dp->e2d_reclen. When entries are deleted from a directory, the
97 * space is returned to the previous entry in the same directory
98 * block by increasing its dp->e2d_reclen. If the first entry of
99 * a directory block is free, then its dp->e2d_ino is set to 0.
100 * Entries other than the first in a directory do not normally have
101 * dp->e2d_ino set to 0.
102 * Ext2 rev 0 has a 16 bits e2d_namlen. For Ext2 vev 1 this has been split
103 * into a 8 bits e2d_namlen and 8 bits e2d_type (looks like ffs, isnt't it ? :)
104 * It's safe to use this for rev 0 as well because all ext2 are little-endian.
105 */
106
107 #define EXT2FS_MAXNAMLEN 255
108
109 struct ext2fs_direct {
110 uint32_t e2d_ino; /* inode number of entry */
111 uint16_t e2d_reclen; /* length of this record */
112 uint8_t e2d_namlen; /* length of string in d_name */
113 uint8_t e2d_type; /* file type */
114 char e2d_name[EXT2FS_MAXNAMLEN];/* name with length<=EXT2FS_MAXNAMLEN */
115 };
116
117 /* Ext2 directory file types (not the same as FFS. Sigh.) */
118 #define EXT2_FT_UNKNOWN 0
119 #define EXT2_FT_REG_FILE 1
120 #define EXT2_FT_DIR 2
121 #define EXT2_FT_CHRDEV 3
122 #define EXT2_FT_BLKDEV 4
123 #define EXT2_FT_FIFO 5
124 #define EXT2_FT_SOCK 6
125 #define EXT2_FT_SYMLINK 7
126
127 #define EXT2_FT_MAX 8
128
129 #define E2IFTODT(mode) (((mode) & 0170000) >> 12)
130
131 static __inline uint8_t inot2ext2dt(uint16_t) __unused;
132 static __inline uint8_t
inot2ext2dt(uint16_t type)133 inot2ext2dt(uint16_t type)
134 {
135
136 switch (type) {
137 case E2IFTODT(EXT2_IFIFO):
138 return EXT2_FT_FIFO;
139 case E2IFTODT(EXT2_IFCHR):
140 return EXT2_FT_CHRDEV;
141 case E2IFTODT(EXT2_IFDIR):
142 return EXT2_FT_DIR;
143 case E2IFTODT(EXT2_IFBLK):
144 return EXT2_FT_BLKDEV;
145 case E2IFTODT(EXT2_IFREG):
146 return EXT2_FT_REG_FILE;
147 case E2IFTODT(EXT2_IFLNK):
148 return EXT2_FT_SYMLINK;
149 case E2IFTODT(EXT2_IFSOCK):
150 return EXT2_FT_SOCK;
151 default:
152 return 0;
153 }
154 }
155
156 /*
157 * The EXT2FS_DIRSIZ macro gives the minimum record length which will hold
158 * the directory entryfor a name len "len" (without the terminating null byte).
159 * This requires the amount of space in struct direct
160 * without the d_name field, plus enough space for the name without a
161 * terminating null byte, rounded up to a 4 byte boundary.
162 */
163 #define EXT2FS_DIRSIZ(len) roundup2(8 + len, 4)
164
165 /*
166 * Template for manipulating directories. Should use struct direct's,
167 * but the name field is EXT2FS_MAXNAMLEN - 1, and this just won't do.
168 */
169 struct ext2fs_dirtemplate {
170 uint32_t dot_ino;
171 int16_t dot_reclen;
172 uint8_t dot_namlen;
173 uint8_t dot_type;
174 char dot_name[4]; /* must be multiple of 4 */
175 uint32_t dotdot_ino;
176 int16_t dotdot_reclen;
177 uint8_t dotdot_namlen;
178 uint8_t dotdot_type;
179 char dotdot_name[4]; /* ditto */
180 };
181
182 #endif /* !_UFS_EXT2FS_EXT2FS_DIR_H_ */
183