1 /* $NetBSD: dosfs.h,v 1.8 2015/01/02 06:21:28 mlelstv Exp $ */ 2 3 /* 4 * Copyright (C) 1995, 1996, 1997 Wolfgang Solfrank 5 * Copyright (c) 1995 Martin Husemann 6 * Some structure declaration borrowed from Paul Popelka 7 * (paulp@uts.amdahl.com), see sys/fs/msdosfs/ for reference. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR 19 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 20 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 21 * IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY DIRECT, INDIRECT, 22 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 23 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 25 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 27 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 28 */ 29 30 #ifndef DOSFS_H 31 #define DOSFS_H 32 33 #define DOSBOOTBLOCKSIZE 512 34 35 typedef u_int32_t cl_t; /* type holding a cluster number */ 36 37 /* 38 * architecture independent description of all the info stored in a 39 * FAT boot block. 40 */ 41 struct bootblock { 42 u_int BytesPerSec; /* bytes per sector */ 43 u_int SecPerClust; /* sectors per cluster */ 44 u_int ResSectors; /* number of reserved sectors */ 45 u_int FATs; /* number of FATs */ 46 u_int RootDirEnts; /* number of root directory entries */ 47 u_int Media; /* media descriptor */ 48 u_int FATsmall; /* number of sectors per FAT */ 49 u_int SecPerTrack; /* sectors per track */ 50 u_int Heads; /* number of heads */ 51 u_int32_t Sectors; /* total number of sectors */ 52 u_int32_t HiddenSecs; /* # of hidden sectors */ 53 u_int32_t HugeSectors; /* # of sectors if bpbSectors == 0 */ 54 u_int FSInfo; /* FSInfo sector */ 55 u_int Backup; /* Backup of Bootblocks */ 56 cl_t RootCl; /* Start of Root Directory */ 57 cl_t FSFree; /* Number of free clusters acc. FSInfo */ 58 cl_t FSNext; /* Next free cluster acc. FSInfo */ 59 60 /* and some more calculated values */ 61 u_int flags; /* some flags: */ 62 #define FAT32 1 /* this is a FAT32 filesystem */ 63 /* 64 * Maybe, we should separate out 65 * various parts of FAT32? XXX 66 */ 67 int ValidFat; /* valid fat if FAT32 non-mirrored */ 68 cl_t ClustMask; /* mask for entries in FAT */ 69 cl_t NumClusters; /* # of entries in a FAT */ 70 u_int32_t NumSectors; /* how many sectors are there */ 71 u_int32_t FATsecs; /* how many sectors are in FAT */ 72 u_int32_t NumFatEntries; /* how many entries really are there */ 73 u_int FirstCluster; /* at what sector is Cluster CLUST_FIRST */ 74 u_int ClusterSize; /* Cluster size in bytes */ 75 76 /* Now some statistics: */ 77 u_int NumFiles; /* # of plain files */ 78 u_int NumFree; /* # of free clusters */ 79 u_int NumBad; /* # of bad clusters */ 80 }; 81 82 struct fatEntry { 83 cl_t next; /* pointer to next cluster */ 84 cl_t head; /* pointer to start of chain */ 85 u_int32_t length; /* number of clusters on chain */ 86 int flags; /* see below */ 87 }; 88 89 #define CLUST_FREE 0 /* 0 means cluster is free */ 90 #define CLUST_FIRST 2 /* 2 is the minimum valid cluster number */ 91 #define CLUST_RSRVD 0xfffffff6 /* start of reserved clusters */ 92 #define CLUST_BAD 0xfffffff7 /* a cluster with a defect */ 93 #define CLUST_EOFS 0xfffffff8 /* start of EOF indicators */ 94 #define CLUST_EOF 0xffffffff /* standard value for last cluster */ 95 96 /* 97 * Masks for cluster values 98 */ 99 #define CLUST12_MASK 0xfff 100 #define CLUST16_MASK 0xffff 101 #define CLUST32_MASK 0xfffffff 102 103 #define FAT_USED 1 /* This fat chain is used in a file */ 104 105 #define DOSLONGNAMELEN 256 /* long name maximal length */ 106 #define LRFIRST 0x40 /* first long name record */ 107 #define LRNOMASK 0x1f /* mask to extract long record 108 * sequence number */ 109 110 /* 111 * Architecture independent description of a directory entry 112 */ 113 struct dosDirEntry { 114 struct dosDirEntry 115 *parent, /* previous tree level */ 116 *next, /* next brother */ 117 *child; /* if this is a directory */ 118 char name[8+1+3+1]; /* alias name first part */ 119 char lname[DOSLONGNAMELEN]; /* real name */ 120 uint flags; /* attributes */ 121 cl_t head; /* cluster no */ 122 u_int32_t size; /* filesize in bytes */ 123 uint fsckflags; /* flags during fsck */ 124 }; 125 /* Flags in fsckflags: */ 126 #define DIREMPTY 1 127 #define DIREMPWARN 2 128 129 /* 130 * TODO-list of unread directories 131 */ 132 struct dirTodoNode { 133 struct dosDirEntry *dir; 134 struct dirTodoNode *next; 135 }; 136 137 #endif 138