xref: /freebsd/sbin/fsck_msdosfs/dosfs.h (revision 4f29da19bd44f0e99f021510460a81bf754c21d2)
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  * $FreeBSD$
35  */
36 
37 #ifndef DOSFS_H
38 #define DOSFS_H
39 
40 #define DOSBOOTBLOCKSIZE 512
41 
42 typedef	u_int32_t	cl_t;	/* type holding a cluster number */
43 
44 /*
45  * architecture independent description of all the info stored in a
46  * FAT boot block.
47  */
48 struct bootblock {
49 	u_int	BytesPerSec;		/* bytes per sector */
50 	u_int	SecPerClust;		/* sectors per cluster */
51 	u_int	ResSectors;		/* number of reserved sectors */
52 	u_int	FATs;			/* number of FATs */
53 	u_int	RootDirEnts;		/* number of root directory entries */
54 	u_int	Media;			/* media descriptor */
55 	u_int	FATsmall;		/* number of sectors per FAT */
56 	u_int	SecPerTrack;		/* sectors per track */
57 	u_int	Heads;			/* number of heads */
58 	u_int32_t Sectors;		/* total number of sectors */
59 	u_int32_t HiddenSecs;		/* # of hidden sectors */
60 	u_int32_t HugeSectors;		/* # of sectors if bpbSectors == 0 */
61 	u_int	FSInfo;			/* FSInfo sector */
62 	u_int	Backup;			/* Backup of Bootblocks */
63 	cl_t	RootCl;			/* Start of Root Directory */
64 	cl_t	FSFree;			/* Number of free clusters acc. FSInfo */
65 	cl_t	FSNext;			/* Next free cluster acc. FSInfo */
66 
67 	/* and some more calculated values */
68 	u_int	flags;			/* some flags: */
69 #define	FAT32		1		/* this is a FAT32 file system */
70 					/*
71 					 * Maybe, we should separate out
72 					 * various parts of FAT32?	XXX
73 					 */
74 	int	ValidFat;		/* valid fat if FAT32 non-mirrored */
75 	cl_t	ClustMask;		/* mask for entries in FAT */
76 	cl_t	NumClusters;		/* # of entries in a FAT */
77 	u_int32_t NumSectors;		/* how many sectors are there */
78 	u_int32_t FATsecs;		/* how many sectors are in FAT */
79 	u_int32_t NumFatEntries;	/* how many entries really are there */
80 	u_int	ClusterOffset;		/* at what sector would sector 0 start */
81 	u_int	ClusterSize;		/* Cluster size in bytes */
82 
83 	/* Now some statistics: */
84 	u_int	NumFiles;		/* # of plain files */
85 	u_int	NumFree;		/* # of free clusters */
86 	u_int	NumBad;			/* # of bad clusters */
87 };
88 
89 struct fatEntry {
90 	cl_t	next;			/* pointer to next cluster */
91 	cl_t	head;			/* pointer to start of chain */
92 	u_int32_t length;		/* number of clusters on chain */
93 	int	flags;			/* see below */
94 };
95 
96 #define	CLUST_FREE	0		/* 0 means cluster is free */
97 #define	CLUST_FIRST	2		/* 2 is the minimum valid cluster number */
98 #define	CLUST_RSRVD	0xfffffff6	/* start of reserved clusters */
99 #define	CLUST_BAD	0xfffffff7	/* a cluster with a defect */
100 #define	CLUST_EOFS	0xfffffff8	/* start of EOF indicators */
101 #define	CLUST_EOF	0xffffffff	/* standard value for last cluster */
102 
103 /*
104  * Masks for cluster values
105  */
106 #define	CLUST12_MASK	0xfff
107 #define	CLUST16_MASK	0xffff
108 #define	CLUST32_MASK	0xfffffff
109 
110 #define	FAT_USED	1		/* This fat chain is used in a file */
111 
112 #define	DOSLONGNAMELEN	256		/* long name maximal length */
113 #define LRFIRST		0x40		/* first long name record */
114 #define	LRNOMASK	0x1f		/* mask to extract long record
115 					 * sequence number */
116 
117 /*
118  * Architecture independent description of a directory entry
119  */
120 struct dosDirEntry {
121 	struct dosDirEntry
122 		*parent,		/* previous tree level */
123 		*next,			/* next brother */
124 		*child;			/* if this is a directory */
125 	char name[8+1+3+1];		/* alias name first part */
126 	char lname[DOSLONGNAMELEN];	/* real name */
127 	uint flags;			/* attributes */
128 	cl_t head;			/* cluster no */
129 	u_int32_t size;			/* filesize in bytes */
130 	uint fsckflags;			/* flags during fsck */
131 };
132 /* Flags in fsckflags: */
133 #define	DIREMPTY	1
134 #define	DIREMPWARN	2
135 
136 /*
137  *  TODO-list of unread directories
138  */
139 struct dirTodoNode {
140 	struct dosDirEntry *dir;
141 	struct dirTodoNode *next;
142 };
143 
144 #endif
145