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/* $NetBSD: bpb.h,v 1.5 1995/07/24 06:37:15 leo 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
*/
/*
* BIOS Parameter Block (BPB) for DOS 3.3
*/
struct bpb33 {
u_int16_t bpbBytesPerSec; /* bytes per sector */
u_int8_t bpbSecPerClust; /* sectors per cluster */
u_int16_t bpbResSectors; /* number of reserved sectors */
u_int8_t bpbFATs; /* number of FATs */
u_int16_t bpbRootDirEnts; /* number of root directory entries */
u_int16_t bpbSectors; /* total number of sectors */
u_int8_t bpbMedia; /* media descriptor */
u_int16_t bpbFATsecs; /* number of sectors per FAT */
u_int16_t bpbSecPerTrack; /* sectors per track */
u_int16_t bpbHeads; /* number of heads */
u_int16_t 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_int16_t bpbBytesPerSec; /* bytes per sector */
u_int8_t bpbSecPerClust; /* sectors per cluster */
u_int16_t bpbResSectors; /* number of reserved sectors */
u_int8_t bpbFATs; /* number of FATs */
u_int16_t bpbRootDirEnts; /* number of root directory entries */
u_int16_t bpbSectors; /* total number of sectors */
u_int8_t bpbMedia; /* media descriptor */
u_int16_t bpbFATsecs; /* number of sectors per FAT */
u_int16_t bpbSecPerTrack; /* sectors per track */
u_int16_t bpbHeads; /* number of heads */
u_int32_t bpbHiddenSecs; /* # of hidden sectors */
u_int32_t bpbHugeSectors; /* # of sectors if bpbSectors == 0 */
};
#ifdef atari
/*
* BPB for gemdos filesystems. Atari leaves the obsolete stuff undefined.
* Currently there is no need for a separate BPB structure.
*/
#if 0
struct bpb_a {
u_int16_t bpbBytesPerSec; /* bytes per sector */
u_int8_t bpbSecPerClust; /* sectors per cluster */
u_int16_t bpbResSectors; /* number of reserved sectors */
u_int8_t bpbFATs; /* number of FATs */
u_int16_t bpbRootDirEnts; /* number of root directory entries */
u_int16_t bpbSectors; /* total number of sectors */
u_int8_t bpbUseless1; /* meaningless on gemdos fs */
u_int16_t bpbFATsecs; /* number of sectors per FAT */
u_int16_t bpbUseless2; /* meaningless for harddisk fs */
u_int16_t bpbUseless3; /* meaningless for harddisk fs */
u_int16_t bpbHiddenSecs; /* the TOS-BIOS ignores this */
};
#endif
#endif /* atari */
/*
* 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.
*
* XXX The little-endian code here assumes that the processor can access
* 16-bit and 32-bit quantities on byte boundaries. If this is not true,
* use the macros for the big-endian case.
*/
#include <machine/endian.h>
#if (BYTE_ORDER == LITTLE_ENDIAN) && defined(UNALIGNED_ACCESS)
#define getushort(x) *((u_int16_t *)(x))
#define getulong(x) *((u_int32_t *)(x))
#define putushort(p, v) (*((u_int16_t *)(p)) = (v))
#define putulong(p, v) (*((u_int32_t *)(p)) = (v))
#else
#define getushort(x) (((u_int8_t *)(x))[0] + (((u_int8_t *)(x))[1] << 8))
#define getulong(x) (((u_int8_t *)(x))[0] + (((u_int8_t *)(x))[1] << 8) \
+ (((u_int8_t *)(x))[2] << 16) \
+ (((u_int8_t *)(x))[3] << 24))
#define putushort(p, v) (((u_int8_t *)(p))[0] = (v), \
((u_int8_t *)(p))[1] = (v) >> 8)
#define putulong(p, v) (((u_int8_t *)(p))[0] = (v), \
((u_int8_t *)(p))[1] = (v) >> 8, \
((u_int8_t *)(p))[2] = (v) >> 16,\
((u_int8_t *)(p))[3] = (v) >> 24)
#endif
/*
* BIOS Parameter Block (BPB) for DOS 3.3
*/
struct byte_bpb33 {
int8_t bpbBytesPerSec[2]; /* bytes per sector */
int8_t bpbSecPerClust; /* sectors per cluster */
int8_t bpbResSectors[2]; /* number of reserved sectors */
int8_t bpbFATs; /* number of FATs */
int8_t bpbRootDirEnts[2]; /* number of root directory entries */
int8_t bpbSectors[2]; /* total number of sectors */
int8_t bpbMedia; /* media descriptor */
int8_t bpbFATsecs[2]; /* number of sectors per FAT */
int8_t bpbSecPerTrack[2]; /* sectors per track */
int8_t bpbHeads[2]; /* number of heads */
int8_t 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 {
int8_t bpbBytesPerSec[2]; /* bytes per sector */
int8_t bpbSecPerClust; /* sectors per cluster */
int8_t bpbResSectors[2]; /* number of reserved sectors */
int8_t bpbFATs; /* number of FATs */
int8_t bpbRootDirEnts[2]; /* number of root directory entries */
int8_t bpbSectors[2]; /* total number of sectors */
int8_t bpbMedia; /* media descriptor */
int8_t bpbFATsecs[2]; /* number of sectors per FAT */
int8_t bpbSecPerTrack[2]; /* sectors per track */
int8_t bpbHeads[2]; /* number of heads */
int8_t bpbHiddenSecs[4]; /* number of hidden sectors */
int8_t bpbHugeSectors[4]; /* # of sectors if bpbSectors == 0 */
};
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