NetBSD/sys/pcfs/bpb.h
cgd 5cc382fc66 add support for PCFS, the MSDOS filesystem.
written by Paul Popelka (paulp@uts.amdahl.com) (patch 129)

invoke w/"options PCFS" in kernel config file.
1993-04-09 19:37:49 +00:00

112 lines
3.8 KiB
C

/*
* 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: /cvsroot/src/sys/pcfs/Attic/bpb.h,v 1.1 1993/04/09 19:37:53 cgd Exp $
*
*/
/*
* BIOS Parameter Block (BPB) for DOS 3.3
*/
struct bpb33 {
u_short bpbBytesPerSec; /* bytes per sector */
u_char bpbSecPerClust; /* sectors per cluster */
u_short bpbResSectors; /* number of reserved sectors */
u_char bpbFATs; /* number of FATs */
u_short bpbRootDirEnts; /* number of root directory entries */
u_short bpbSectors; /* total number of sectors */
u_char bpbMedia; /* media descriptor */
u_short bpbFATsecs; /* number of sectors per FAT */
u_short bpbSecPerTrack; /* sectors per track */
u_short bpbHeads; /* number of heads */
u_short bpbHiddenSecs; /* number of hidden sectors */
};
/*
* BPB for DOS 5.0
* The difference is bpbHiddenSecs is a short for DOS 3.3,
* and bpbHugeSectors is not in the 3.3 bpb.
*/
struct bpb50 {
u_short bpbBytesPerSec; /* bytes per sector */
u_char bpbSecPerClust; /* sectors per cluster */
u_short bpbResSectors; /* number of reserved sectors */
u_char bpbFATs; /* number of FATs */
u_short bpbRootDirEnts; /* number of root directory entries */
u_short bpbSectors; /* total number of sectors */
u_char bpbMedia; /* media descriptor */
u_short bpbFATsecs; /* number of sectors per FAT */
u_short bpbSecPerTrack; /* sectors per track */
u_short bpbHeads; /* number of heads */
u_long bpbHiddenSecs; /* number of hidden sectors */
u_long bpbHugeSectors; /* number of sectrs if bpbSectors == 0 */
};
/*
* The following structures represent how the bpb's look
* on disk. shorts and longs are just character arrays
* of the appropriate length. This is because the compiler
* forces shorts and longs to align on word or halfword
* boundaries.
*/
#include <machine/endian.h>
#if BYTE_ORDER == LITTLE_ENDIAN
#define getushort(x) *((u_short *)(x))
#define getulong(x) *((u_long *)(x))
#define putushort(p, v) (*((u_short *)(p)) = (v))
#define putulong(p, v) (*((u_long *)(p)) = (v))
#else
#endif
/*
* BIOS Parameter Block (BPB) for DOS 3.3
*/
struct byte_bpb33 {
char bpbBytesPerSec[2]; /* bytes per sector */
char bpbSecPerClust; /* sectors per cluster */
char bpbResSectors[2]; /* number of reserved sectors */
char bpbFATs; /* number of FATs */
char bpbRootDirEnts[2]; /* number of root directory entries */
char bpbSectors[2]; /* total number of sectors */
char bpbMedia; /* media descriptor */
char bpbFATsecs[2]; /* number of sectors per FAT */
char bpbSecPerTrack[2]; /* sectors per track */
char bpbHeads[2]; /* number of heads */
char bpbHiddenSecs[2]; /* number of hidden sectors */
};
/*
* BPB for DOS 5.0
* The difference is bpbHiddenSecs is a short for DOS 3.3,
* and bpbHugeSectors is not in the 3.3 bpb.
*/
struct byte_bpb50 {
char bpbBytesPerSec[2]; /* bytes per sector */
char bpbSecPerClust; /* sectors per cluster */
char bpbResSectors[2]; /* number of reserved sectors */
char bpbFATs; /* number of FATs */
char bpbRootDirEnts[2]; /* number of root directory entries */
char bpbSectors[2]; /* total number of sectors */
char bpbMedia; /* media descriptor */
char bpbFATsecs[2]; /* number of sectors per FAT */
char bpbSecPerTrack[2]; /* sectors per track */
char bpbHeads[2]; /* number of heads */
char bpbHiddenSecs[4]; /* number of hidden sectors */
char bpbHugeSectors[4]; /* number of sectrs if bpbSectors == 0 */
};