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/*
* Mach Operating System
* Copyright (c) 1991,1990 Carnegie Mellon University
* All Rights Reserved.
*
* Permission to use, copy, modify and distribute this software and its
* documentation is hereby granted, provided that both the copyright
* notice and this permission notice appear in all copies of the
* software, derivative works or modified versions, and any portions
* thereof, and that both notices appear in supporting documentation.
*
* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
* ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
*
* Carnegie Mellon requests users of this software to return to
*
* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
* School of Computer Science
* Carnegie Mellon University
* Pittsburgh PA 15213-3890
*
* any improvements or extensions that they make and grant Carnegie Mellon
* the rights to redistribute these changes.
*/
/*
* Copyright (c) 1982, 1986, 1989 The Regents of the University of California.
* All rights reserved.
*
* Redistribution and use in source and binary forms are permitted
* provided that the above copyright notice and this paragraph are
* duplicated in all such forms and that any documentation,
* advertising materials, and other materials related to such
* distribution and use acknowledge that the software was developed
* by the University of California, Berkeley. The name of the
* University may not be used to endorse or promote products derived
* from this software without specific prior written permission.
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*
* @(#)dir.h 7.6 (Berkeley) 5/9/89
*/
#ifndef _BOOT_UFS_DIR_H_
#define _BOOT_UFS_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
{
unsigned int d_ino; /* inode number of entry */
unsigned short d_reclen; /* length of this record */
unsigned 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.
*/
#undef DIRSIZ
#define DIRSIZ(dp) \
((sizeof (struct direct) - (MAXNAMLEN+1)) + (((dp)->d_namlen+1 + 3) &~ 3))
#ifdef KERNEL
/*
* Template for manipulating directories.
* Should use struct direct's, but the name field
* is MAXNAMLEN - 1, and this just won't do.
*/
struct dirtemplate
{
unsigned int dot_ino;
short dot_reclen;
short dot_namlen;
char dot_name[4]; /* must be multiple of 4 */
unsigned int dotdot_ino;
short dotdot_reclen;
short dotdot_namlen;
char dotdot_name[4]; /* ditto */
};
#endif
/*
* The following information should be obtained from <dirent.h>
* and is provided solely (and temporarily) for backward compatibility.
*/
#ifndef KERNEL
#define d_fileno d_ino /* compatibility with POSIX */
#ifndef DEV_BSIZE
#define DEV_BSIZE 512
#endif
/*
* Definitions for library routines operating on directories.
*/
typedef struct _dirdesc
{
int dd_fd;
int dd_loc;
int dd_size;
char dd_buf[DIRBLKSIZ];
}
DIR;
#define dirfd(dirp) ((dirp)->dd_fd)
#ifndef NULL
#define NULL 0
#endif
#endif /* not KERNEL */
#endif /* _BOOT_UFS_DIR_H_ */
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