sys/pcfs/bootsect.h

/*
 *  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
 *
 *      $Header: /usr/src/CVS/sys/pcfs/bootsect.h,v 1.1.2.1 1993/02/07 21:57:06 friedl Exp $
 *
 */

/*
 *  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 {
        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[474];   /* pad so structure is 512 bytes long   */
        u_short bsBootSectSig;
#define BOOTSIG 0xaa55
};

struct bootsector50 {
        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