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 */ 38 39 #ifndef _UFS_UFS_DIR_H_ 40 #define _UFS_UFS_DIR_H_ 41 42 /* 43 * Theoretically, directories can be more than 2Gb in length, however, in 44 * practice this seems unlikely. So, we define the type doff_t as a 32-bit 45 * quantity to keep down the cost of doing lookup on a 32-bit machine. 46 */ 47 #define doff_t int32_t 48 #define MAXDIRSIZE (0x7fffffff) 49 50 /* 51 * A directory consists of some number of blocks of DIRBLKSIZ 52 * bytes, where DIRBLKSIZ is chosen such that it can be transferred 53 * to disk in a single atomic operation (e.g. 512 bytes on most machines). 54 * 55 * Each DIRBLKSIZ byte block contains some number of directory entry 56 * structures, which are of variable length. Each directory entry has 57 * a struct direct at the front of it, containing its inode number, 58 * the length of the entry, and the length of the name contained in 59 * the entry. These are followed by the name padded to a 4 byte boundary 60 * with null bytes. All names are guaranteed null terminated. 61 * The maximum length of a name in a directory is UFS_MAXNAMLEN. 62 * 63 * The macro DIRSIZ(fmt, dp) gives the amount of space required to represent 64 * a directory entry. Free space in a directory is represented by 65 * entries which have dp->d_reclen > DIRSIZ(fmt, dp). All DIRBLKSIZ bytes 66 * in a directory block are claimed by the directory entries. This 67 * usually results in the last entry in a directory having a large 68 * dp->d_reclen. When entries are deleted from a directory, the 69 * space is returned to the previous entry in the same directory 70 * block by increasing its dp->d_reclen. If the first entry of 71 * a directory block is free, then its dp->d_ino is set to 0. 72 * Entries other than the first in a directory do not normally have 73 * dp->d_ino set to 0. 74 */ 75 #define DIRBLKSIZ DEV_BSIZE 76 #define UFS_MAXNAMLEN 255 77 78 struct direct { 79 uint32_t d_ino; /* inode number of entry */ 80 uint16_t d_reclen; /* length of this record */ 81 uint8_t d_type; /* file type, see below */ 82 uint8_t d_namlen; /* length of string in d_name */ 83 char d_name[UFS_MAXNAMLEN + 1]; 84 /* name with length <= UFS_MAXNAMLEN */ 85 }; 86 87 /* 88 * File types 89 */ 90 #define DT_UNKNOWN 0 91 #define DT_FIFO 1 92 #define DT_CHR 2 93 #define DT_DIR 4 94 #define DT_BLK 6 95 #define DT_REG 8 96 #define DT_LNK 10 97 #define DT_SOCK 12 98 #define DT_WHT 14 99 100 /* 101 * Convert between stat structure types and directory types. 102 */ 103 #define IFTODT(mode) (((mode) & 0170000) >> 12) 104 #define DTTOIF(dirtype) ((dirtype) << 12) 105 106 /* 107 * The DIRSIZ macro gives the minimum record length which will hold 108 * the directory entry. This requires the amount of space in struct direct 109 * without the d_name field, plus enough space for the name with a terminating 110 * null byte (dp->d_namlen + 1), rounded up to a 4 byte boundary. 111 */ 112 #define DIR_ROUNDUP 4 /* Directory name roundup size */ 113 #define DIRECTSIZ(namlen) \ 114 (roundup2(__offsetof(struct direct, d_name) + (namlen) + 1, DIR_ROUNDUP)) 115 #if (BYTE_ORDER == LITTLE_ENDIAN) 116 #define DIRSIZ(oldfmt, dp) \ 117 ((oldfmt) ? DIRECTSIZ((dp)->d_type) : DIRECTSIZ((dp)->d_namlen)) 118 #else 119 #define DIRSIZ(oldfmt, dp) \ 120 DIRECTSIZ((dp)->d_namlen) 121 #endif 122 #define OLDDIRFMT 1 123 #define NEWDIRFMT 0 124 125 /* 126 * Template for manipulating directories. Should use struct direct's, 127 * but the name field is UFS_MAXNAMLEN - 1, and this just won't do. 128 */ 129 struct dirtemplate { 130 uint32_t dot_ino; 131 int16_t dot_reclen; 132 uint8_t dot_type; 133 uint8_t dot_namlen; 134 char dot_name[4]; /* must be multiple of 4 */ 135 uint32_t dotdot_ino; 136 int16_t dotdot_reclen; 137 uint8_t dotdot_type; 138 uint8_t dotdot_namlen; 139 char dotdot_name[4]; /* ditto */ 140 }; 141 142 /* 143 * This is the old format of directories, sanz type element. 144 */ 145 struct odirtemplate { 146 uint32_t dot_ino; 147 int16_t dot_reclen; 148 uint16_t dot_namlen; 149 char dot_name[4]; /* must be multiple of 4 */ 150 uint32_t dotdot_ino; 151 int16_t dotdot_reclen; 152 uint16_t dotdot_namlen; 153 char dotdot_name[4]; /* ditto */ 154 }; 155 #endif /* !_DIR_H_ */ 156