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/* Modified from BSD by Michael I. Bushnell for GNU Hurd ufs server. */
/*
* 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 8.2 (Berkeley) 1/21/94
*/
#ifndef _DIR_H_
#define _DIR_H_
#include <endian.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(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->d_reclen > DIRSIZ(fmt, 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
/* Don't call this struct DIRECT because the library defines that
(sometimes) in a possible different way. */
struct directory_entry {
u_long d_ino; /* inode number of entry */
u_short d_reclen; /* length of this record */
u_char d_type; /* file type, see below */
u_char d_namlen; /* length of string in d_name */
char d_name[MAXNAMLEN + 1]; /* name with length <= MAXNAMLEN */
};
/* Return the type from a struct directory_entry, paying attention to whether
this filesystem supports the type extension */
#define DIRECT_TYPE(dp) (direct_symlink_extension ? (dp)->d_type : DT_UNKNOWN)
/* Return the namlen from a struct direct, paying attention to whether
this filesystem supports the type extension */
#if (BYTE_ORDER == LITTLE_ENDIAN)
#define DIRECT_NAMLEN(dp) (direct_symlink_extension || swab_disk \
? (dp)->d_namlen \
: (dp)->(dp)->d_type)
#else
#define DIRECT_NAMLEN(dp) ((dp)->d_namlen)
#endif
/*
* 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.
*/
/* In BSD this macro takes a struct direct. Modified by MIB here to
take the namelen (as computed by strlen). */
#define DIRSIZ(namelen) \
((sizeof (struct directory_entry) - (MAXNAMLEN+1)) + (((namelen)+1 + 3) &~ 3))
#if 0 /* This is the BSD definition */
#if (BYTE_ORDER == LITTLE_ENDIAN)
#define DIRSIZ(oldfmt, dp) \
((oldfmt) ? \
((sizeof (struct direct) - (MAXNAMLEN+1)) + (((dp)->d_type+1 + 3) &~ 3)) : \
((sizeof (struct direct) - (MAXNAMLEN+1)) + (((dp)->d_namlen+1 + 3) &~ 3)))
#else
#define DIRSIZ(oldfmt, dp) \
((sizeof (struct direct) - (MAXNAMLEN+1)) + (((dp)->d_namlen+1 + 3) &~ 3))
#endif
#endif /* 0 */
#define OLDDIRFMT 1
#define NEWDIRFMT 0
#if 0 /* Not used in GNU */
/*
* 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;
u_char dot_type;
u_char dot_namlen;
char dot_name[4]; /* must be multiple of 4 */
u_long dotdot_ino;
short dotdot_reclen;
u_char dotdot_type;
u_char dotdot_namlen;
char dotdot_name[4]; /* ditto */
};
/*
* This is the old format of directories, sanz type element.
*/
struct odirtemplate {
u_long dot_ino;
short dot_reclen;
u_short dot_namlen;
char dot_name[4]; /* must be multiple of 4 */
u_long dotdot_ino;
short dotdot_reclen;
u_short dotdot_namlen;
char dotdot_name[4]; /* ditto */
};
#endif /* 0 */
#endif /* !_DIR_H_ */
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