xref: /dragonfly/sbin/fsck_msdosfs/dosfs.h (revision b40e316c)
1 /*
2  * Copyright (C) 1995, 1996, 1997 Wolfgang Solfrank
3  * Copyright (c) 1995 Martin Husemann
4  * Some structure declaration borrowed from Paul Popelka
5  * (paulp@uts.amdahl.com), see /sys/msdosfs/ for reference.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *	This product includes software developed by Martin Husemann
18  *	and Wolfgang Solfrank.
19  * 4. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR
24  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
25  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
26  * IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY DIRECT, INDIRECT,
27  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
28  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
29  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
30  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
31  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
32  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33  *	$NetBSD: dosfs.h,v 1.4 1997/01/03 14:32:48 ws Exp $
34  * $FreeBSD: src/sbin/fsck_msdosfs/dosfs.h,v 1.1.2.1 2001/08/01 05:47:56 obrien Exp $
35  * $DragonFly: src/sbin/fsck_msdosfs/dosfs.h,v 1.2 2003/06/17 04:27:32 dillon Exp $
36  */
37 
38 #ifndef DOSFS_H
39 #define DOSFS_H
40 
41 #define DOSBOOTBLOCKSIZE 512
42 
43 typedef	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  */
49 struct 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 
90 struct 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  */
121 struct 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  */
140 struct dirTodoNode {
141 	struct dosDirEntry *dir;
142 	struct dirTodoNode *next;
143 };
144 
145 #endif
146