1 /* $OpenBSD: ext2fs_dir.h,v 1.5 2001/09/18 00:25:59 art Exp $ */ 2 /* $NetBSD: ext2fs_dir.h,v 1.4 2000/01/28 16:00:23 bouyer Exp $ */ 3 4 /* 5 * Copyright (c) 1997 Manuel Bouyer. 6 * Copyright (c) 1982, 1986, 1989, 1993 7 * The Regents of the University of California. All rights reserved. 8 * (c) UNIX System Laboratories, Inc. 9 * All or some portions of this file are derived from material licensed 10 * to the University of California by American Telephone and Telegraph 11 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 12 * the permission of UNIX System Laboratories, Inc. 13 * 14 * Redistribution and use in source and binary forms, with or without 15 * modification, are permitted provided that the following conditions 16 * are met: 17 * 1. Redistributions of source code must retain the above copyright 18 * notice, this list of conditions and the following disclaimer. 19 * 2. Redistributions in binary form must reproduce the above copyright 20 * notice, this list of conditions and the following disclaimer in the 21 * documentation and/or other materials provided with the distribution. 22 * 3. All advertising materials mentioning features or use of this software 23 * must display the following acknowledgement: 24 * This product includes software developed by the University of 25 * California, Berkeley and its contributors. 26 * 4. Neither the name of the University nor the names of its contributors 27 * may be used to endorse or promote products derived from this software 28 * without specific prior written permission. 29 * 30 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 31 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 32 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 33 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 34 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 35 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 36 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 37 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 38 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 39 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 40 * SUCH DAMAGE. 41 * 42 * @(#)dir.h 8.4 (Berkeley) 8/10/94 43 * Modified for ext2fs by Manuel Bouyer. 44 */ 45 46 #ifndef _EXT2FS_DIR_H_ 47 #define _EXT2FS_DIR_H_ 48 49 /* 50 * Theoretically, directories can be more than 2Gb in length, however, in 51 * practice this seems unlikely. So, we define the type doff_t as a 32-bit 52 * quantity to keep down the cost of doing lookup on a 32-bit machine. 53 */ 54 #define doff_t int32_t 55 #define EXT2FS_MAXDIRSIZE (0x7fffffff) 56 57 /* 58 * A directory consists of some number of blocks of e2fs_bsize bytes. 59 * 60 * Each block contains some number of directory entry 61 * structures, which are of variable length. Each directory entry has 62 * a struct direct at the front of it, containing its inode number, 63 * the length of the entry, and the length of the name contained in 64 * the entry. These are followed by the name padded to a 4 byte boundary 65 * with null bytes. All names are guaranteed null terminated. 66 * The maximum length of a name in a directory is EXT2FS_MAXNAMLEN. 67 * 68 * The macro EXT2FS_DIRSIZ(fmt, dp) gives the amount of space required to 69 * represent a directory entry. Free space in a directory is represented by 70 * entries which have dp->e2d_reclen > DIRSIZ(fmt, dp). All d2fs_bsize bytes 71 * in a directory block are claimed by the directory entries. This 72 * usually results in the last entry in a directory having a large 73 * dp->e2d_reclen. When entries are deleted from a directory, the 74 * space is returned to the previous entry in the same directory 75 * block by increasing its dp->e2d_reclen. If the first entry of 76 * a directory block is free, then its dp->e2d_ino is set to 0. 77 * Entries other than the first in a directory do not normally have 78 * dp->e2d_ino set to 0. 79 * Ext2 rev 0 has a 16 bits e2d_namlen. For Ext2 vev 1 this has been split 80 * into a 8 bits e2d_namlen and 8 bits e2d_type (looks like ffs, isnt't it ? :) 81 * It's safe to use this for rev 0 as well because all ext2 are little-endian. 82 */ 83 84 #define EXT2FS_MAXNAMLEN 255 85 86 struct ext2fs_direct { 87 u_int32_t e2d_ino; /* inode number of entry */ 88 u_int16_t e2d_reclen; /* length of this record */ 89 u_int8_t e2d_namlen; /* length of string in d_name */ 90 u_int8_t e2d_type; /* file type */ 91 char e2d_name[EXT2FS_MAXNAMLEN];/* name with length <= EXT2FS_MAXNAMLEN */ 92 }; 93 94 /* Ext2 directory file types (not the same as FFS. Sigh. */ 95 #define EXT2_FT_UNKNOWN 0 96 #define EXT2_FT_REG_FILE 1 97 #define EXT2_FT_DIR 2 98 #define EXT2_FT_CHRDEV 3 99 #define EXT2_FT_BLKDEV 4 100 #define EXT2_FT_FIFO 5 101 #define EXT2_FT_SOCK 6 102 #define EXT2_FT_SYMLINK 7 103 104 #define EXT2_FT_MAX 8 105 106 #define E2IFTODT(mode) (((mode) & 0170000) >> 12) 107 108 static __inline__ u_int8_t inot2ext2dt __P((u_int16_t)) 109 __attribute__((__unused__)); 110 static __inline__ u_int8_t 111 inot2ext2dt(type) 112 u_int16_t type; 113 { 114 switch(type) { 115 case E2IFTODT(EXT2_IFIFO): 116 return EXT2_FT_FIFO; 117 case E2IFTODT(EXT2_IFCHR): 118 return EXT2_FT_CHRDEV; 119 case E2IFTODT(EXT2_IFDIR): 120 return EXT2_FT_DIR; 121 case E2IFTODT(EXT2_IFBLK): 122 return EXT2_FT_BLKDEV; 123 case E2IFTODT(EXT2_IFREG): 124 return EXT2_FT_REG_FILE; 125 case E2IFTODT(EXT2_IFLNK): 126 return EXT2_FT_SYMLINK; 127 case E2IFTODT(EXT2_IFSOCK): 128 return EXT2_FT_SOCK; 129 default: 130 return 0; 131 } 132 } 133 134 /* 135 * The EXT2FS_DIRSIZ macro gives the minimum record length which will hold 136 * the directory entryfor a name len "len" (without the terminating null byte). 137 * This requires the amount of space in struct direct 138 * without the d_name field, plus enough space for the name without a 139 * terminating null byte, rounded up to a 4 byte boundary. 140 */ 141 #define EXT2FS_DIRSIZ(len) \ 142 (( 8 + len + 3) &~ 3) 143 144 /* 145 * Template for manipulating directories. Should use struct direct's, 146 * but the name field is EXT2FS_MAXNAMLEN - 1, and this just won't do. 147 */ 148 struct ext2fs_dirtemplate { 149 u_int32_t dot_ino; 150 int16_t dot_reclen; 151 u_int8_t dot_namlen; 152 u_int8_t dot_type; 153 char dot_name[4]; /* must be multiple of 4 */ 154 u_int32_t dotdot_ino; 155 int16_t dotdot_reclen; 156 u_int8_t dotdot_namlen; 157 u_int8_t dotdot_type; 158 char dotdot_name[4]; /* ditto */ 159 }; 160 161 #endif /* !_EXT2FS_DIR_H_ */ 162