/* * Copyright (c) 1982, 1986, 1989 The Regents of the University of California. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the University of * California, Berkeley and its contributors. * 4. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * from: @(#)dir.h 7.10 (Berkeley) 3/25/91 * $Id: dir.h,v 1.2 1993/10/16 18:17:37 rgrimes Exp $ */ #ifndef _DIR_H_ #define _DIR_H_ /* * A directory consists of some number of blocks of DIRBLKSIZ * bytes, where DIRBLKSIZ is chosen such that it can be transferred * to disk in a single atomic operation (e.g. 512 bytes on most machines). * * Each DIRBLKSIZ byte block contains some number of directory entry * structures, which are of variable length. Each directory entry has * a struct direct at the front of it, containing its inode number, * the length of the entry, and the length of the name contained in * the entry. These are followed by the name padded to a 4 byte boundary * with null bytes. All names are guaranteed null terminated. * The maximum length of a name in a directory is MAXNAMLEN. * * The macro DIRSIZ(dp) gives the amount of space required to represent * a directory entry. Free space in a directory is represented by * entries which have dp->d_reclen > DIRSIZ(dp). All DIRBLKSIZ bytes * in a directory block are claimed by the directory entries. This * usually results in the last entry in a directory having a large * dp->d_reclen. When entries are deleted from a directory, the * space is returned to the previous entry in the same directory * block by increasing its dp->d_reclen. If the first entry of * a directory block is free, then its dp->d_ino is set to 0. * Entries other than the first in a directory do not normally have * dp->d_ino set to 0. */ #define DIRBLKSIZ DEV_BSIZE #define MAXNAMLEN 255 struct direct { u_long d_ino; /* inode number of entry */ u_short d_reclen; /* length of this record */ u_short d_namlen; /* length of string in d_name */ char d_name[MAXNAMLEN + 1]; /* name with length <= MAXNAMLEN */ }; /* * The DIRSIZ macro gives the minimum record length which will hold * the directory entry. This requires the amount of space in struct direct * without the d_name field, plus enough space for the name with a terminating * null byte (dp->d_namlen+1), rounded up to a 4 byte boundary. */ #define DIRSIZ(dp) \ ((sizeof (struct direct) - (MAXNAMLEN+1)) + (((dp)->d_namlen+1 + 3) &~ 3)) /* * Template for manipulating directories. * Should use struct direct's, but the name field * is MAXNAMLEN - 1, and this just won't do. */ struct dirtemplate { u_long dot_ino; short dot_reclen; short dot_namlen; char dot_name[4]; /* must be multiple of 4 */ u_long dotdot_ino; short dotdot_reclen; short dotdot_namlen; char dotdot_name[4]; /* ditto */ }; #endif /* !_DIR_H_ */