1 /* 2 * Copyright (c) 1982, 1986, 1989, 1993 3 * The Regents of the University of California. All rights reserved. 4 * (c) UNIX System Laboratories, Inc. 5 * All or some portions of this file are derived from material licensed 6 * to the University of California by American Telephone and Telegraph 7 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 8 * the permission of UNIX System Laboratories, Inc. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the University of 21 * California, Berkeley and its contributors. 22 * 4. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 * 38 * @(#)dir.h 8.2 (Berkeley) 1/21/94 39 * $FreeBSD: src/sys/ufs/ufs/dir.h,v 1.9 1999/08/28 00:52:27 peter Exp $ 40 */ 41 42 #ifndef _UFS_UFS_DIR_H_ 43 #define _UFS_UFS_DIR_H_ 44 45 /* 46 * Theoretically, directories can be more than 2Gb in length, however, in 47 * practice this seems unlikely. So, we define the type doff_t as a 32-bit 48 * quantity to keep down the cost of doing lookup on a 32-bit machine. 49 */ 50 #define doff_t int32_t 51 #define MAXDIRSIZE (0x7fffffff) 52 53 /* 54 * A directory consists of some number of blocks of DIRBLKSIZ 55 * bytes, where DIRBLKSIZ is chosen such that it can be transferred 56 * to disk in a single atomic operation (e.g. 512 bytes on most machines). 57 * 58 * Each DIRBLKSIZ byte block contains some number of directory entry 59 * structures, which are of variable length. Each directory entry has 60 * a struct direct at the front of it, containing its inode number, 61 * the length of the entry, and the length of the name contained in 62 * the entry. These are followed by the name padded to a 4 byte boundary 63 * with null bytes. All names are guaranteed null terminated. 64 * The maximum length of a name in a directory is MAXNAMLEN. 65 * 66 * The macro DIRSIZ(fmt, dp) gives the amount of space required to represent 67 * a directory entry. Free space in a directory is represented by 68 * entries which have dp->d_reclen > DIRSIZ(fmt, dp). All DIRBLKSIZ bytes 69 * in a directory block are claimed by the directory entries. This 70 * usually results in the last entry in a directory having a large 71 * dp->d_reclen. When entries are deleted from a directory, the 72 * space is returned to the previous entry in the same directory 73 * block by increasing its dp->d_reclen. If the first entry of 74 * a directory block is free, then its dp->d_ino is set to 0. 75 * Entries other than the first in a directory do not normally have 76 * dp->d_ino set to 0. 77 */ 78 #define DIRBLKSIZ DEV_BSIZE 79 #define MAXNAMLEN 255 80 81 struct direct { 82 u_int32_t d_ino; /* inode number of entry */ 83 u_int16_t d_reclen; /* length of this record */ 84 u_int8_t d_type; /* file type, see below */ 85 u_int8_t d_namlen; /* length of string in d_name */ 86 char d_name[MAXNAMLEN + 1];/* name with length <= MAXNAMLEN */ 87 }; 88 89 /* 90 * File types 91 */ 92 #define DT_UNKNOWN 0 93 #define DT_FIFO 1 94 #define DT_CHR 2 95 #define DT_DIR 4 96 #define DT_BLK 6 97 #define DT_REG 8 98 #define DT_LNK 10 99 #define DT_SOCK 12 100 #define DT_WHT 14 101 102 /* 103 * Convert between stat structure types and directory types. 104 */ 105 #define IFTODT(mode) (((mode) & 0170000) >> 12) 106 #define DTTOIF(dirtype) ((dirtype) << 12) 107 108 /* 109 * The DIRSIZ macro gives the minimum record length which will hold 110 * the directory entry. This requires the amount of space in struct direct 111 * without the d_name field, plus enough space for the name with a terminating 112 * null byte (dp->d_namlen+1), rounded up to a 4 byte boundary. 113 * 114 * 115 */ 116 #define DIRECTSIZ(namlen) \ 117 (((int)&((struct direct *)0)->d_name + \ 118 ((namlen)+1)*sizeof(((struct direct *)0)->d_name[0]) + 3) & ~3) 119 #if (BYTE_ORDER == LITTLE_ENDIAN) 120 #define DIRSIZ(oldfmt, dp) \ 121 ((oldfmt) ? DIRECTSIZ((dp)->d_type) : DIRECTSIZ((dp)->d_namlen)) 122 #else 123 #define DIRSIZ(oldfmt, dp) \ 124 DIRECTSIZ((dp)->d_namlen) 125 #endif 126 #define OLDDIRFMT 1 127 #define NEWDIRFMT 0 128 129 /* 130 * Template for manipulating directories. Should use struct direct's, 131 * but the name field is MAXNAMLEN - 1, and this just won't do. 132 */ 133 struct dirtemplate { 134 u_int32_t dot_ino; 135 int16_t dot_reclen; 136 u_int8_t dot_type; 137 u_int8_t dot_namlen; 138 char dot_name[4]; /* must be multiple of 4 */ 139 u_int32_t dotdot_ino; 140 int16_t dotdot_reclen; 141 u_int8_t dotdot_type; 142 u_int8_t dotdot_namlen; 143 char dotdot_name[4]; /* ditto */ 144 }; 145 146 /* 147 * This is the old format of directories, sanz type element. 148 */ 149 struct odirtemplate { 150 u_int32_t dot_ino; 151 int16_t dot_reclen; 152 u_int16_t dot_namlen; 153 char dot_name[4]; /* must be multiple of 4 */ 154 u_int32_t dotdot_ino; 155 int16_t dotdot_reclen; 156 u_int16_t dotdot_namlen; 157 char dotdot_name[4]; /* ditto */ 158 }; 159 #endif /* !_DIR_H_ */ 160