dosfs.h revision 1.5 
1/*	$OpenBSD: dosfs.h,v 1.5 1998/01/11 20:40:31 provos Exp $	*/
2/*	$NetBSD: dosfs.h,v 1.5 1997/10/17 11:19:41 ws Exp $	*/
3
4/*
5 * Copyright (C) 1995, 1996, 1997 Wolfgang Solfrank
6 * Copyright (c) 1995 Martin Husemann
7 * Some structure declaration borrowed from Paul Popelka
8 * (paulp@uts.amdahl.com), see /sys/msdosfs/ for reference.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 * 3. All advertising materials mentioning features or use of this software
19 *    must display the following acknowledgement:
20 *	This product includes software developed by Martin Husemann
21 *	and Wolfgang Solfrank.
22 * 4. Neither the name of the University nor the names of its contributors
23 *    may be used to endorse or promote products derived from this software
24 *    without specific prior written permission.
25 *
26 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR
27 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
28 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
29 * IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY DIRECT, INDIRECT,
30 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
31 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
32 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
33 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
34 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
35 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
36 */
37
38#ifndef DOSFS_H
39#define DOSFS_H
40
41#define DOSBOOTBLOCKSIZE 512
42
43typedef	u_int32_t	cl_t;	/* type holding a cluster number */
44
45/*
46 * architecture independent description of all the info stored in a
47 * FAT boot block.
48 */
49struct bootblock {
50	u_int	BytesPerSec;		/* bytes per sector */
51	u_int	SecPerClust;		/* sectors per cluster */
52	u_int	ResSectors;		/* number of reserved sectors */
53	u_int	FATs;			/* number of FATs */
54	u_int	RootDirEnts;		/* number of root directory entries */
55	u_int	Media;			/* media descriptor */
56	u_int	FATsmall;		/* number of sectors per FAT */
57	u_int	SecPerTrack;		/* sectors per track */
58	u_int	Heads;			/* number of heads */
59	u_int32_t Sectors;		/* total number of sectors */
60	u_int32_t HiddenSecs;		/* # of hidden sectors */
61	u_int32_t HugeSectors;		/* # of sectors if bpbSectors == 0 */
62	u_int	FSInfo;			/* FSInfo sector */
63	u_int	Backup;			/* Backup of Bootblocks */
64	cl_t	RootCl;			/* Start of Root Directory */
65	cl_t	FSFree;			/* Number of free clusters acc. FSInfo */
66	cl_t	FSNext;			/* Next free cluster acc. FSInfo */
67
68	/* and some more calculated values */
69	u_int	flags;			/* some flags: */
70#define	FAT32		1		/* this is a FAT32 filesystem */
71					/*
72					 * Maybe, we should separate out
73					 * various parts of FAT32?	XXX
74					 */
75	int	ValidFat;		/* valid fat if FAT32 non-mirrored */
76	cl_t	ClustMask;		/* mask for entries in FAT */
77	cl_t	NumClusters;		/* # of entries in a FAT */
78	u_int32_t NumSectors;		/* how many sectors are there */
79	u_int32_t FATsecs;		/* how many sectors are in FAT */
80	u_int32_t NumFatEntries;	/* how many entries really are there */
81	u_int	ClusterOffset;		/* at what sector would sector 0 start */
82	u_int	ClusterSize;		/* Cluster size in bytes */
83
84	/* Now some statistics: */
85	u_int	NumFiles;		/* # of plain files */
86	u_int	NumFree;		/* # of free clusters */
87	u_int	NumBad;			/* # of bad clusters */
88};
89
90struct fatEntry {
91	cl_t	next;			/* pointer to next cluster */
92	cl_t	head;			/* pointer to start of chain */
93	u_int32_t length;		/* number of clusters on chain */
94	int	flags;			/* see below */
95};
96
97#define	CLUST_FREE	0		/* 0 means cluster is free */
98#define	CLUST_FIRST	2		/* 2 is the minimum valid cluster number */
99#define	CLUST_RSRVD	0xfffffff6	/* start of reserved clusters */
100#define	CLUST_BAD	0xfffffff7	/* a cluster with a defect */
101#define	CLUST_EOFS	0xfffffff8	/* start of EOF indicators */
102#define	CLUST_EOF	0xffffffff	/* standard value for last cluster */
103
104/*
105 * Masks for cluster values
106 */
107#define	CLUST12_MASK	0xfff
108#define	CLUST16_MASK	0xffff
109#define	CLUST32_MASK	0xfffffff
110
111#define	FAT_USED	1		/* This fat chain is used in a file */
112
113#define	DOSLONGNAMELEN	256		/* long name maximal length */
114#define LRFIRST		0x40		/* first long name record */
115#define	LRNOMASK	0x1f		/* mask to extract long record
116					 * sequence number */
117
118/*
119 * Architecture independent description of a directory entry
120 */
121struct dosDirEntry {
122	struct dosDirEntry
123		*parent,		/* previous tree level */
124		*next,			/* next brother */
125		*child;			/* if this is a directory */
126	char name[8+1+3+1];		/* alias name first part */
127	char lname[DOSLONGNAMELEN];	/* real name */
128	uint flags;			/* attributes */
129	cl_t head;			/* cluster no */
130	u_int32_t size;			/* filesize in bytes */
131	uint fsckflags;			/* flags during fsck */
132};
133/* Flags in fsckflags: */
134#define	DIREMPTY	1
135#define	DIREMPWARN	2
136
137/*
138 *  TODO-list of unread directories
139 */
140struct dirTodoNode {
141	struct dosDirEntry *dir;
142	struct dirTodoNode *next;
143};
144
145#endif
146