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/* $OpenBSD: ext2fs_dir.h,v 1.3 1997/06/12 21:09:32 downsj Exp $ */
/* $NetBSD: ext2fs_dir.h,v 1.1 1997/06/11 09:33:50 bouyer Exp $ */
/*
* Copyright (c) 1997 Manuel Bouyer.
* Copyright (c) 1982, 1986, 1989, 1993
* The Regents of the University of California. All rights reserved.
* (c) UNIX System Laboratories, Inc.
* All or some portions of this file are derived from material licensed
* to the University of California by American Telephone and Telegraph
* Co. or Unix System Laboratories, Inc. and are reproduced herein with
* the permission of UNIX System Laboratories, Inc.
*
* 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.
*
* @(#)dir.h 8.4 (Berkeley) 8/10/94
* Modified for ext2fs by Manuel Bouyer.
*/
#ifndef _EXT2FS_DIR_H_
#define _EXT2FS_DIR_H_
/*
* Theoretically, directories can be more than 2Gb in length, however, in
* practice this seems unlikely. So, we define the type doff_t as a 32-bit
* quantity to keep down the cost of doing lookup on a 32-bit machine.
*/
#define doff_t int32_t
#define EXT2FS_MAXDIRSIZE (0x7fffffff)
/*
* A directory consists of some number of blocks of e2fs_bsize bytes.
*
* Each 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 EXT2FS_MAXNAMLEN.
*
* The macro EXT2FS_DIRSIZ(fmt, dp) gives the amount of space required to
* represent a directory entry. Free space in a directory is represented by
* entries which have dp->e2d_reclen > DIRSIZ(fmt, dp). All d2fs_bsize 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->e2d_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->e2d_reclen. If the first entry of
* a directory block is free, then its dp->e2d_ino is set to 0.
* Entries other than the first in a directory do not normally have
* dp->e2d_ino set to 0.
*/
#define EXT2FS_MAXNAMLEN 255
struct ext2fs_direct {
u_int32_t e2d_ino; /* inode number of entry */
u_int16_t e2d_reclen; /* length of this record */
u_int16_t e2d_namlen; /* length of string in d_name */
char e2d_name[EXT2FS_MAXNAMLEN];/* name with length <= EXT2FS_MAXNAMLEN */
};
/*
* The EXT2FS_DIRSIZ macro gives the minimum record length which will hold
* the directory entryfor a name len "len" (without the terminating null byte).
* This requires the amount of space in struct direct
* without the d_name field, plus enough space for the name without a
* terminating null byte, rounded up to a 4 byte boundary.
*/
#define EXT2FS_DIRSIZ(len) \
(( 8 + len + 3) &~ 3)
/*
* Template for manipulating directories. Should use struct direct's,
* but the name field is EXT2FS_MAXNAMLEN - 1, and this just won't do.
*/
struct ext2fs_dirtemplate {
u_int32_t dot_ino;
int16_t dot_reclen;
u_int16_t dot_namlen;
char dot_name[4]; /* must be multiple of 4 */
u_int32_t dotdot_ino;
int16_t dotdot_reclen;
u_int16_t dotdot_namlen;
char dotdot_name[4]; /* ditto */
};
#endif /* !_EXT2FS_DIR_H_ */
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