summaryrefslogtreecommitdiff
path: root/sys/ufs/ext2fs/ext2fs_dir.h
blob: ae73124ee95b22300a257c962fdf838096b0db5e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
/*	$OpenBSD: ext2fs_dir.h,v 1.4 2000/04/26 23:24:40 jasoni 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_int8_t e2d_namlen;		/* length of string in d_name */
	u_int8_t e2d_type;		/* file type */
	char	  e2d_name[EXT2FS_MAXNAMLEN];/* name with length <= EXT2FS_MAXNAMLEN */
};

/* Ext2 directory file types (not the same as FFS. Sigh. */
#define EXT2_FT_UNKNOWN         0
#define EXT2_FT_REG_FILE        1 
#define EXT2_FT_DIR             2
#define EXT2_FT_CHRDEV          3
#define EXT2_FT_BLKDEV          4
#define EXT2_FT_FIFO            5
#define EXT2_FT_SOCK            6
#define EXT2_FT_SYMLINK         7
#define EXT2_FT_MAX             8

#define E2IFTODT(mode)    (((mode) & 0170000) >> 12)

static __inline__ u_int8_t inot2ext2dt __P((u_int16_t))
    __attribute__((__unused__));
static __inline__ u_int8_t
inot2ext2dt(type)
	u_int16_t type;
{
	switch(type) {
	case E2IFTODT(EXT2_IFIFO):
		return EXT2_FT_FIFO;
	case E2IFTODT(EXT2_IFCHR):
		return EXT2_FT_CHRDEV;
	case E2IFTODT(EXT2_IFDIR):
		return EXT2_FT_DIR;
	case E2IFTODT(EXT2_IFBLK):
		return EXT2_FT_BLKDEV;
	case E2IFTODT(EXT2_IFREG):
		return EXT2_FT_REG_FILE;
	case E2IFTODT(EXT2_IFLNK):
		return EXT2_FT_SYMLINK;
	case E2IFTODT(EXT2_IFSOCK):
		return EXT2_FT_SOCK;
	default:
		return 0;
	}
}

/*
 * 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_int8_t	dot_namlen;
	u_int8_t	dot_type;
	char		dot_name[4];	/* must be multiple of 4 */
	u_int32_t	dotdot_ino;
	int16_t		dotdot_reclen;
	u_int8_t	dotdot_namlen;
	u_int8_t	dotdot_type;
	char		dotdot_name[4];	/* ditto */
};

#endif /* !_EXT2FS_DIR_H_ */