1 | /* $NetBSD: ext2fs_dir.h,v 1.22 2016/08/07 01:47:11 kre 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 <sys/dirent.h> |
71 | #include <ufs/ext2fs/ext2fs_dinode.h> |
72 | |
73 | /* |
74 | * Theoretically, directories can be more than 2Gb in length, however, in |
75 | * practice this seems unlikely. So, we define the type doff_t as a 32-bit |
76 | * quantity to keep down the cost of doing lookup on a 32-bit machine. |
77 | */ |
78 | #define doff_t int32_t |
79 | #define EXT2FS_MAXDIRSIZE INT32_MAX |
80 | |
81 | /* |
82 | * A directory consists of some number of blocks of e2fs_bsize bytes. |
83 | * |
84 | * Each block contains some number of directory entry |
85 | * structures, which are of variable length. Each directory entry has |
86 | * a struct direct at the front of it, containing its inode number, |
87 | * the length of the entry, and the length of the name contained in |
88 | * the entry. These are followed by the name padded to a 4 byte boundary |
89 | * with null bytes. All names are guaranteed null terminated. |
90 | * The maximum length of a name in a directory is EXT2FS_MAXNAMLEN. |
91 | * |
92 | * The macro EXT2FS_DIRSIZ(fmt, dp) gives the amount of space required to |
93 | * represent a directory entry. Free space in a directory is represented by |
94 | * entries which have dp->e2d_reclen > DIRSIZ(fmt, dp). All d2fs_bsize bytes |
95 | * in a directory block are claimed by the directory entries. This |
96 | * usually results in the last entry in a directory having a large |
97 | * dp->e2d_reclen. When entries are deleted from a directory, the |
98 | * space is returned to the previous entry in the same directory |
99 | * block by increasing its dp->e2d_reclen. If the first entry of |
100 | * a directory block is free, then its dp->e2d_ino is set to 0. |
101 | * Entries other than the first in a directory do not normally have |
102 | * dp->e2d_ino set to 0. |
103 | * Ext2 rev 0 has a 16 bits e2d_namlen. For Ext2 vev 1 this has been split |
104 | * into a 8 bits e2d_namlen and 8 bits e2d_type (looks like ffs, isnt't it ? :) |
105 | * It's safe to use this for rev 0 as well because all ext2 are little-endian. |
106 | */ |
107 | |
108 | #define EXT2FS_MAXNAMLEN 255 |
109 | |
110 | struct ext2fs_direct { |
111 | uint32_t e2d_ino; /* inode number of entry */ |
112 | uint16_t e2d_reclen; /* length of this record */ |
113 | uint8_t e2d_namlen; /* length of string in d_name */ |
114 | uint8_t e2d_type; /* file type */ |
115 | char e2d_name[EXT2FS_MAXNAMLEN];/* name with length<=EXT2FS_MAXNAMLEN */ |
116 | }; |
117 | |
118 | enum ext2fs_slotstatus { |
119 | NONE, |
120 | COMPACT, |
121 | FOUND |
122 | }; |
123 | |
124 | struct ext2fs_searchslot { |
125 | enum ext2fs_slotstatus slotstatus; |
126 | doff_t slotoffset; /* offset of area with free space */ |
127 | int slotsize; /* size of area at slotoffset */ |
128 | int slotfreespace; /* amount of space free in slot */ |
129 | int slotneeded; /* sizeof the entry we are seeking */ |
130 | }; |
131 | |
132 | /* Ext2 directory file types (not the same as FFS. Sigh.) */ |
133 | #define EXT2_FT_UNKNOWN 0 |
134 | #define EXT2_FT_REG_FILE 1 |
135 | #define EXT2_FT_DIR 2 |
136 | #define EXT2_FT_CHRDEV 3 |
137 | #define EXT2_FT_BLKDEV 4 |
138 | #define EXT2_FT_FIFO 5 |
139 | #define EXT2_FT_SOCK 6 |
140 | #define EXT2_FT_SYMLINK 7 |
141 | |
142 | #define EXT2_FT_MAX 8 |
143 | |
144 | #define E2IFTODT(mode) (((mode) & 0170000) >> 12) |
145 | |
146 | static __inline uint8_t inot2ext2dt(uint16_t) __unused; |
147 | static __inline uint8_t |
148 | inot2ext2dt(uint16_t type) |
149 | { |
150 | |
151 | switch (type) { |
152 | case E2IFTODT(EXT2_IFIFO): |
153 | return EXT2_FT_FIFO; |
154 | case E2IFTODT(EXT2_IFCHR): |
155 | return EXT2_FT_CHRDEV; |
156 | case E2IFTODT(EXT2_IFDIR): |
157 | return EXT2_FT_DIR; |
158 | case E2IFTODT(EXT2_IFBLK): |
159 | return EXT2_FT_BLKDEV; |
160 | case E2IFTODT(EXT2_IFREG): |
161 | return EXT2_FT_REG_FILE; |
162 | case E2IFTODT(EXT2_IFLNK): |
163 | return EXT2_FT_SYMLINK; |
164 | case E2IFTODT(EXT2_IFSOCK): |
165 | return EXT2_FT_SOCK; |
166 | default: |
167 | return 0; |
168 | } |
169 | } |
170 | |
171 | static __inline uint8_t ext2dt2dt(uint8_t) __unused; |
172 | static __inline uint8_t |
173 | ext2dt2dt(uint8_t type) |
174 | { |
175 | switch (type) { |
176 | case EXT2_FT_REG_FILE: |
177 | return DT_FIFO; |
178 | case EXT2_FT_DIR: |
179 | return DT_DIR; |
180 | case EXT2_FT_CHRDEV: |
181 | return DT_CHR; |
182 | case EXT2_FT_BLKDEV: |
183 | return DT_BLK; |
184 | case EXT2_FT_FIFO: |
185 | return DT_FIFO; |
186 | case EXT2_FT_SOCK: |
187 | return DT_SOCK; |
188 | case EXT2_FT_SYMLINK: |
189 | return DT_LNK; |
190 | default: |
191 | return DT_UNKNOWN; |
192 | } |
193 | } |
194 | |
195 | /* |
196 | * The EXT2FS_DIRSIZ macro gives the minimum record length which will hold |
197 | * the directory entryfor a name len "len" (without the terminating null byte). |
198 | * This requires the amount of space in struct direct |
199 | * without the d_name field, plus enough space for the name without a |
200 | * terminating null byte, rounded up to a 4 byte boundary. |
201 | */ |
202 | #define EXT2FS_DIRSIZ(len) roundup2(8 + len, 4) |
203 | |
204 | /* |
205 | * Template for manipulating directories. Should use struct direct's, |
206 | * but the name field is EXT2FS_MAXNAMLEN - 1, and this just won't do. |
207 | */ |
208 | struct ext2fs_dirtemplate { |
209 | uint32_t dot_ino; |
210 | int16_t dot_reclen; |
211 | uint8_t dot_namlen; |
212 | uint8_t dot_type; |
213 | char dot_name[4]; /* must be multiple of 4 */ |
214 | uint32_t dotdot_ino; |
215 | int16_t dotdot_reclen; |
216 | uint8_t dotdot_namlen; |
217 | uint8_t dotdot_type; |
218 | char dotdot_name[4]; /* ditto */ |
219 | }; |
220 | |
221 | /* |
222 | * EXT2_DIR_PAD defines the directory entries boundaries |
223 | * |
224 | * NOTE: It must be a multiple of 4 |
225 | */ |
226 | #define EXT2_DIR_PAD 4 |
227 | #define EXT2_DIR_ROUND (EXT2_DIR_PAD - 1) |
228 | #define EXT2_DIR_REC_LEN(namelen) \ |
229 | (((namelen) + 8 + EXT2_DIR_ROUND) & ~EXT2_DIR_ROUND) |
230 | |
231 | #endif /* !_UFS_EXT2FS_EXT2FS_DIR_H_ */ |
232 | |