1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 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 8.2 (Berkeley) 1/21/94 37 * $FreeBSD$ 38 */ 39 40 #ifndef _UFS_UFS_DIR_H_ 41 #define _UFS_UFS_DIR_H_ 42 43 /* 44 * Theoretically, directories can be more than 2Gb in length, however, in 45 * practice this seems unlikely. So, we define the type doff_t as a 32-bit 46 * quantity to keep down the cost of doing lookup on a 32-bit machine. 47 */ 48 #define doff_t int32_t 49 #define MAXDIRSIZE (0x7fffffff) 50 51 /* 52 * A directory consists of some number of blocks of DIRBLKSIZ 53 * bytes, where DIRBLKSIZ is chosen such that it can be transferred 54 * to disk in a single atomic operation (e.g. 512 bytes on most machines). 55 * 56 * Each DIRBLKSIZ byte block contains some number of directory entry 57 * structures, which are of variable length. Each directory entry has 58 * a struct direct at the front of it, containing its inode number, 59 * the length of the entry, and the length of the name contained in 60 * the entry. These are followed by the name padded to a 4 byte boundary 61 * with null bytes. All names are guaranteed null terminated. 62 * The maximum length of a name in a directory is UFS_MAXNAMLEN. 63 * 64 * The macro DIRSIZ(fmt, dp) gives the amount of space required to represent 65 * a directory entry. Free space in a directory is represented by 66 * entries which have dp->d_reclen > DIRSIZ(fmt, dp). All DIRBLKSIZ bytes 67 * in a directory block are claimed by the directory entries. This 68 * usually results in the last entry in a directory having a large 69 * dp->d_reclen. When entries are deleted from a directory, the 70 * space is returned to the previous entry in the same directory 71 * block by increasing its dp->d_reclen. If the first entry of 72 * a directory block is free, then its dp->d_ino is set to 0. 73 * Entries other than the first in a directory do not normally have 74 * dp->d_ino set to 0. 75 */ 76 #define DIRBLKSIZ DEV_BSIZE 77 #define UFS_MAXNAMLEN 255 78 79 struct direct { 80 u_int32_t d_ino; /* inode number of entry */ 81 u_int16_t d_reclen; /* length of this record */ 82 u_int8_t d_type; /* file type, see below */ 83 u_int8_t d_namlen; /* length of string in d_name */ 84 char d_name[UFS_MAXNAMLEN + 1]; 85 /* name with length <= UFS_MAXNAMLEN */ 86 }; 87 88 /* 89 * File types 90 */ 91 #define DT_UNKNOWN 0 92 #define DT_FIFO 1 93 #define DT_CHR 2 94 #define DT_DIR 4 95 #define DT_BLK 6 96 #define DT_REG 8 97 #define DT_LNK 10 98 #define DT_SOCK 12 99 #define DT_WHT 14 100 101 /* 102 * Convert between stat structure types and directory types. 103 */ 104 #define IFTODT(mode) (((mode) & 0170000) >> 12) 105 #define DTTOIF(dirtype) ((dirtype) << 12) 106 107 /* 108 * The DIRSIZ macro gives the minimum record length which will hold 109 * the directory entry. This requires the amount of space in struct direct 110 * without the d_name field, plus enough space for the name with a terminating 111 * null byte (dp->d_namlen + 1), rounded up to a 4 byte boundary. 112 */ 113 #define DIR_ROUNDUP 4 /* Directory name roundup size */ 114 #define DIRECTSIZ(namlen) \ 115 (roundup2(__offsetof(struct direct, d_name) + (namlen) + 1, DIR_ROUNDUP)) 116 #if (BYTE_ORDER == LITTLE_ENDIAN) 117 #define DIRSIZ(oldfmt, dp) \ 118 ((oldfmt) ? DIRECTSIZ((dp)->d_type) : DIRECTSIZ((dp)->d_namlen)) 119 #else 120 #define DIRSIZ(oldfmt, dp) \ 121 DIRECTSIZ((dp)->d_namlen) 122 #endif 123 #define OLDDIRFMT 1 124 #define NEWDIRFMT 0 125 126 /* 127 * Template for manipulating directories. Should use struct direct's, 128 * but the name field is UFS_MAXNAMLEN - 1, and this just won't do. 129 */ 130 struct dirtemplate { 131 u_int32_t dot_ino; 132 int16_t dot_reclen; 133 u_int8_t dot_type; 134 u_int8_t dot_namlen; 135 char dot_name[4]; /* must be multiple of 4 */ 136 u_int32_t dotdot_ino; 137 int16_t dotdot_reclen; 138 u_int8_t dotdot_type; 139 u_int8_t dotdot_namlen; 140 char dotdot_name[4]; /* ditto */ 141 }; 142 143 /* 144 * This is the old format of directories, sanz type element. 145 */ 146 struct odirtemplate { 147 u_int32_t dot_ino; 148 int16_t dot_reclen; 149 u_int16_t dot_namlen; 150 char dot_name[4]; /* must be multiple of 4 */ 151 u_int32_t dotdot_ino; 152 int16_t dotdot_reclen; 153 u_int16_t dotdot_namlen; 154 char dotdot_name[4]; /* ditto */ 155 }; 156 #endif /* !_DIR_H_ */ 157