1 /* $NetBSD: ext2fs_dir.h,v 1.18 2009/10/19 18:41:17 bouyer 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 /* 71 * Theoretically, directories can be more than 2Gb in length, however, in 72 * practice this seems unlikely. So, we define the type doff_t as a 32-bit 73 * quantity to keep down the cost of doing lookup on a 32-bit machine. 74 */ 75 #define doff_t int32_t 76 #define EXT2FS_MAXDIRSIZE INT32_MAX 77 78 /* 79 * A directory consists of some number of blocks of e2fs_bsize bytes. 80 * 81 * Each block contains some number of directory entry 82 * structures, which are of variable length. Each directory entry has 83 * a struct direct at the front of it, containing its inode number, 84 * the length of the entry, and the length of the name contained in 85 * the entry. These are followed by the name padded to a 4 byte boundary 86 * with null bytes. All names are guaranteed null terminated. 87 * The maximum length of a name in a directory is EXT2FS_MAXNAMLEN. 88 * 89 * The macro EXT2FS_DIRSIZ(fmt, dp) gives the amount of space required to 90 * represent a directory entry. Free space in a directory is represented by 91 * entries which have dp->e2d_reclen > DIRSIZ(fmt, dp). All d2fs_bsize bytes 92 * in a directory block are claimed by the directory entries. This 93 * usually results in the last entry in a directory having a large 94 * dp->e2d_reclen. When entries are deleted from a directory, the 95 * space is returned to the previous entry in the same directory 96 * block by increasing its dp->e2d_reclen. If the first entry of 97 * a directory block is free, then its dp->e2d_ino is set to 0. 98 * Entries other than the first in a directory do not normally have 99 * dp->e2d_ino set to 0. 100 * Ext2 rev 0 has a 16 bits e2d_namlen. For Ext2 vev 1 this has been split 101 * into a 8 bits e2d_namlen and 8 bits e2d_type (looks like ffs, isnt't it ? :) 102 * It's safe to use this for rev 0 as well because all ext2 are little-endian. 103 */ 104 105 #define EXT2FS_MAXNAMLEN 255 106 107 struct ext2fs_direct { 108 uint32_t e2d_ino; /* inode number of entry */ 109 uint16_t e2d_reclen; /* length of this record */ 110 uint8_t e2d_namlen; /* length of string in d_name */ 111 uint8_t e2d_type; /* file type */ 112 char e2d_name[EXT2FS_MAXNAMLEN];/* name with length<=EXT2FS_MAXNAMLEN */ 113 }; 114 115 /* Ext2 directory file types (not the same as FFS. Sigh.) */ 116 #define EXT2_FT_UNKNOWN 0 117 #define EXT2_FT_REG_FILE 1 118 #define EXT2_FT_DIR 2 119 #define EXT2_FT_CHRDEV 3 120 #define EXT2_FT_BLKDEV 4 121 #define EXT2_FT_FIFO 5 122 #define EXT2_FT_SOCK 6 123 #define EXT2_FT_SYMLINK 7 124 125 #define EXT2_FT_MAX 8 126 127 #define E2IFTODT(mode) (((mode) & 0170000) >> 12) 128 129 static __inline uint8_t inot2ext2dt(uint16_t) __unused; 130 static __inline uint8_t 131 inot2ext2dt(uint16_t type) 132 { 133 134 switch (type) { 135 case E2IFTODT(EXT2_IFIFO): 136 return EXT2_FT_FIFO; 137 case E2IFTODT(EXT2_IFCHR): 138 return EXT2_FT_CHRDEV; 139 case E2IFTODT(EXT2_IFDIR): 140 return EXT2_FT_DIR; 141 case E2IFTODT(EXT2_IFBLK): 142 return EXT2_FT_BLKDEV; 143 case E2IFTODT(EXT2_IFREG): 144 return EXT2_FT_REG_FILE; 145 case E2IFTODT(EXT2_IFLNK): 146 return EXT2_FT_SYMLINK; 147 case E2IFTODT(EXT2_IFSOCK): 148 return EXT2_FT_SOCK; 149 default: 150 return 0; 151 } 152 } 153 154 /* 155 * The EXT2FS_DIRSIZ macro gives the minimum record length which will hold 156 * the directory entryfor a name len "len" (without the terminating null byte). 157 * This requires the amount of space in struct direct 158 * without the d_name field, plus enough space for the name without a 159 * terminating null byte, rounded up to a 4 byte boundary. 160 */ 161 #define EXT2FS_DIRSIZ(len) roundup2(8 + len, 4) 162 163 /* 164 * Template for manipulating directories. Should use struct direct's, 165 * but the name field is EXT2FS_MAXNAMLEN - 1, and this just won't do. 166 */ 167 struct ext2fs_dirtemplate { 168 uint32_t dot_ino; 169 int16_t dot_reclen; 170 uint8_t dot_namlen; 171 uint8_t dot_type; 172 char dot_name[4]; /* must be multiple of 4 */ 173 uint32_t dotdot_ino; 174 int16_t dotdot_reclen; 175 uint8_t dotdot_namlen; 176 uint8_t dotdot_type; 177 char dotdot_name[4]; /* ditto */ 178 }; 179 180 #endif /* !_UFS_EXT2FS_EXT2FS_DIR_H_ */ 181