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/*-
* 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.
* 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
* $FreeBSD$
*/
#ifndef _UFS_UFS_DIR_H_
#define _UFS_UFS_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 MAXDIRSIZE (0x7fffffff)
/*
* 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
struct direct {
u_int32_t d_ino; /* inode number of entry */
u_int16_t d_reclen; /* length of this record */
u_int8_t d_type; /* file type, see below */
u_int8_t d_namlen; /* length of string in d_name */
char d_name[MAXNAMLEN + 1];/* name with length <= MAXNAMLEN */
};
/*
* File types
*/
#define DT_UNKNOWN 0
#define DT_FIFO 1
#define DT_CHR 2
#define DT_DIR 4
#define DT_BLK 6
#define DT_REG 8
#define DT_LNK 10
#define DT_SOCK 12
#define DT_WHT 14
/*
* Convert between stat structure types and directory types.
*/
#define IFTODT(mode) (((mode) & 0170000) >> 12)
#define DTTOIF(dirtype) ((dirtype) << 12)
/*
* 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 DIR_ROUNDUP 4 /* Directory name roundup size */
#define DIRECTSIZ(namlen) \
(roundup2(__offsetof(struct direct, d_name) + (namlen) + 1, DIR_ROUNDUP))
#if (BYTE_ORDER == LITTLE_ENDIAN)
#define DIRSIZ(oldfmt, dp) \
((oldfmt) ? DIRECTSIZ((dp)->d_type) : DIRECTSIZ((dp)->d_namlen))
#else
#define DIRSIZ(oldfmt, dp) \
DIRECTSIZ((dp)->d_namlen)
#endif
#define OLDDIRFMT 1
#define NEWDIRFMT 0
/*
* 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_int32_t dot_ino;
int16_t dot_reclen;
u_int8_t dot_type;
u_int8_t dot_namlen;
char dot_name[4]; /* must be multiple of 4 */
u_int32_t dotdot_ino;
int16_t dotdot_reclen;
u_int8_t dotdot_type;
u_int8_t dotdot_namlen;
char dotdot_name[4]; /* ditto */
};
/*
* This is the old format of directories, sanz type element.
*/
struct odirtemplate {
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 /* !_DIR_H_ */
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