freebsd-src/sys/msdosfs/bootsect.h
1995-10-31 20:54:33 +00:00

71 lines
2.3 KiB
C

/* $Id: bootsect.h,v 1.2 1995/05/30 08:07:29 rgrimes Exp $ */
/* $NetBSD: bootsect.h,v 1.4 1994/06/29 06:35:28 cgd Exp $ */
/*
* Written by Paul Popelka (paulp@uts.amdahl.com)
*
* You can do anything you want with this software, just don't say you wrote
* it, and don't remove this notice.
*
* This software is provided "as is".
*
* The author supplies this software to be publicly redistributed on the
* understanding that the author is not responsible for the correct
* functioning of this software in any circumstances and is not liable for
* any damages caused by this software.
*
* October 1992
*/
/*
* Format of a boot sector. This is the first sector on a DOS floppy disk
* or the fist sector of a partition on a hard disk. But, it is not the
* first sector of a partitioned hard disk.
*/
struct bootsector33 {
u_char bsJump[3]; /* jump instruction E9xxxx or EBxx90 */
char bsOemName[8]; /* OEM name and version */
char bsBPB[19]; /* BIOS parameter block */
char bsDriveNumber; /* drive number (0x80) */
char bsBootCode[479]; /* pad so structure is 512 bytes long */
u_short bsBootSectSig;
#define BOOTSIG 0xaa55
};
struct bootsector50 {
u_char bsJump[3]; /* jump instruction E9xxxx or EBxx90 */
char bsOemName[8]; /* OEM name and version */
char bsBPB[25]; /* BIOS parameter block */
char bsDriveNumber; /* drive number (0x80) */
char bsReserved1; /* reserved */
char bsBootSignature; /* extended boot signature (0x29) */
#define EXBOOTSIG 0x29
char bsVolumeID[4]; /* volume ID number */
char bsVolumeLabel[11]; /* volume label */
char bsFileSysType[8]; /* file system type (FAT12 or FAT16) */
char bsBootCode[448]; /* pad so structure is 512 bytes long */
u_short bsBootSectSig;
#define BOOTSIG 0xaa55
};
union bootsector {
struct bootsector33 bs33;
struct bootsector50 bs50;
};
/*
* Shorthand for fields in the bpb.
*/
#define bsBytesPerSec bsBPB.bpbBytesPerSec
#define bsSectPerClust bsBPB.bpbSectPerClust
#define bsResSectors bsBPB.bpbResSectors
#define bsFATS bsBPB.bpbFATS
#define bsRootDirEnts bsBPB.bpbRootDirEnts
#define bsSectors bsBPB.bpbSectors
#define bsMedia bsBPB.bpbMedia
#define bsFATsecs bsBPB.bpbFATsecs
#define bsSectPerTrack bsBPB.bpbSectPerTrack
#define bsHeads bsBPB.bpbHeads
#define bsHiddenSecs bsBPB.bpbHiddenSecs
#define bsHugeSectors bsBPB.bpbHugeSectors