1 /* $NetBSD: bootsect.h,v 1.2 2003/10/06 02:21:47 lukem Exp $ */ 2 3 /* 4 * Written by Paul Popelka (paulp@uts.amdahl.com) 5 * 6 * You can do anything you want with this software, just don't say you wrote 7 * it, and don't remove this notice. 8 * 9 * This software is provided "as is". 10 * 11 * The author supplies this software to be publicly redistributed on the 12 * understanding that the author is not responsible for the correct 13 * functioning of this software in any circumstances and is not liable for 14 * any damages caused by this software. 15 * 16 * October 1992 17 */ 18 19 /* 20 * Format of a boot sector. This is the first sector on a DOS floppy disk 21 * or the fist sector of a partition on a hard disk. But, it is not the 22 * first sector of a partitioned hard disk. 23 */ 24 struct bootsector33 { 25 u_int8_t bsJump[3]; /* jump inst E9xxxx or EBxx90 */ 26 int8_t bsOemName[8]; /* OEM name and version */ 27 int8_t bsBPB[19]; /* BIOS parameter block */ 28 int8_t bsDriveNumber; /* drive number (0x80) */ 29 int8_t bsBootCode[479]; /* pad so struct is 512b */ 30 u_int8_t bsBootSectSig0; 31 u_int8_t bsBootSectSig1; 32 #define BOOTSIG0 0x55 33 #define BOOTSIG1 0xaa 34 }; 35 36 struct extboot { 37 int8_t exDriveNumber; /* drive number (0x80) */ 38 int8_t exReserved1; /* reserved */ 39 int8_t exBootSignature; /* ext. boot signature (0x29) */ 40 #define EXBOOTSIG 0x29 41 int8_t exVolumeID[4]; /* volume ID number */ 42 int8_t exVolumeLabel[11]; /* volume label */ 43 int8_t exFileSysType[8]; /* fs type (FAT12 or FAT16) */ 44 }; 45 46 struct bootsector50 { 47 u_int8_t bsJump[3]; /* jump inst E9xxxx or EBxx90 */ 48 int8_t bsOemName[8]; /* OEM name and version */ 49 int8_t bsBPB[25]; /* BIOS parameter block */ 50 int8_t bsExt[26]; /* Bootsector Extension */ 51 int8_t bsBootCode[448]; /* pad so structure is 512b */ 52 u_int8_t bsBootSectSig0; 53 u_int8_t bsBootSectSig1; 54 #define BOOTSIG0 0x55 55 #define BOOTSIG1 0xaa 56 }; 57 58 struct bootsector710 { 59 u_int8_t bsJump[3]; /* jump inst E9xxxx or EBxx90 */ 60 int8_t bsOEMName[8]; /* OEM name and version */ 61 int8_t bsBPB[53]; /* BIOS parameter block */ 62 int8_t bsExt[26]; /* Bootsector Extension */ 63 int8_t bsBootCode[418]; /* pad so structure is 512b */ 64 u_int8_t bsBootSectSig2; /* 2 & 3 are only defined for FAT32? */ 65 u_int8_t bsBootSectSig3; 66 u_int8_t bsBootSectSig0; 67 u_int8_t bsBootSectSig1; 68 #define BOOTSIG0 0x55 69 #define BOOTSIG1 0xaa 70 #define BOOTSIG2 0 71 #define BOOTSIG3 0 72 }; 73 #ifdef atari 74 /* 75 * The boot sector on a gemdos fs is a little bit different from the msdos fs 76 * format. Currently there is no need to declare a separate structure, the 77 * bootsector33 struct will do. 78 */ 79 #if 0 80 struct bootsec_atari { 81 u_int8_t bsBranch[2]; /* branch inst if auto-boot */ 82 int8_t bsFiller[6]; /* anything or nothing */ 83 int8_t bsSerial[3]; /* serial no. for mediachange */ 84 int8_t bsBPB[19]; /* BIOS parameter block */ 85 int8_t bsBootCode[482]; /* pad so struct is 512b */ 86 }; 87 #endif 88 #endif /* atari */ 89 90 union bootsector { 91 struct bootsector33 bs33; 92 struct bootsector50 bs50; 93 struct bootsector710 bs710; 94 }; 95 96 #if 0 97 /* 98 * Shorthand for fields in the bpb. 99 */ 100 #define bsBytesPerSec bsBPB.bpbBytesPerSec 101 #define bsSectPerClust bsBPB.bpbSectPerClust 102 #define bsResSectors bsBPB.bpbResSectors 103 #define bsFATS bsBPB.bpbFATS 104 #define bsRootDirEnts bsBPB.bpbRootDirEnts 105 #define bsSectors bsBPB.bpbSectors 106 #define bsMedia bsBPB.bpbMedia 107 #define bsFATsecs bsBPB.bpbFATsecs 108 #define bsSectPerTrack bsBPB.bpbSectPerTrack 109 #define bsHeads bsBPB.bpbHeads 110 #define bsHiddenSecs bsBPB.bpbHiddenSecs 111 #define bsHugeSectors bsBPB.bpbHugeSectors 112 #endif 113