kernel/hdr/dcb.h

93 lines
4.6 KiB
C

/****************************************************************/
/* */
/* dcb.h */
/* */
/* DOS Device Control Block Structure */
/* */
/* November 20, 1991 */
/* */
/* Copyright (c) 1995 */
/* Pasquale J. Villani */
/* All Rights Reserved */
/* */
/* This file is part of DOS-C. */
/* */
/* DOS-C is free software; you can redistribute it and/or */
/* modify it under the terms of the GNU General Public License */
/* as published by the Free Software Foundation; either version */
/* 2, or (at your option) any later version. */
/* */
/* DOS-C is distributed in the hope that it will be useful, but */
/* WITHOUT ANY WARRANTY; without even the implied warranty of */
/* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See */
/* the GNU General Public License for more details. */
/* */
/* You should have received a copy of the GNU General Public */
/* License along with DOS-C; see the file COPYING. If not, */
/* write to the Free Software Foundation, 675 Mass Ave, */
/* Cambridge, MA 02139, USA. */
/****************************************************************/
#ifdef MAIN
#ifdef VERSION_STRINGS
static BYTE *clock_hRcsId =
"$Id: dcb.h 485 2002-12-09 00:17:15Z bartoldeman $";
#endif
#endif
/* Internal drive parameter block */
struct dpb {
BYTE dpb_unit; /* unit for error reporting */
BYTE dpb_subunit; /* the sub-unit for driver */
UWORD dpb_secsize; /* sector size */
UBYTE dpb_clsmask; /* mask (sectors/cluster-1) */
UBYTE dpb_shftcnt; /* log base 2 of cluster size */
UWORD dpb_fatstrt; /* FAT start sector */
UBYTE dpb_fats; /* # of FAT copies */
UWORD dpb_dirents; /* # of dir entries */
UWORD dpb_data; /* start of data area */
UWORD dpb_size; /* # of clusters+1 on media */
UWORD dpb_fatsize; /* # of sectors / FAT */
UWORD dpb_dirstrt; /* start sec. of root dir */
struct dhdr FAR * /* pointer to device header */
dpb_device;
UBYTE dpb_mdb; /* media descr. byte */
BYTE dpb_flags; /* -1 = force MEDIA CHK */
struct dpb FAR * /* next dpb in chain */
dpb_next; /* -1 = end */
UWORD dpb_cluster; /* cluster # of first free */
/* -1 if not known */
#ifndef WITHFAT32
UWORD dpb_nfreeclst; /* number of free clusters */
/* -1 if not known */
#else
union {
struct {
UWORD dpb_nfreeclst_lo;
UWORD dpb_nfreeclst_hi;
} dpb_nfreeclst_st;
ULONG _dpb_xnfreeclst; /* number of free clusters */
/* -1 if not known */
} dpb_nfreeclst_un;
#define dpb_nfreeclst dpb_nfreeclst_un.dpb_nfreeclst_st.dpb_nfreeclst_lo
#define dpb_xnfreeclst dpb_nfreeclst_un._dpb_xnfreeclst
UWORD dpb_xflags; /* extended flags, see bpb */
UWORD dpb_xfsinfosec; /* FS info sector number, */
/* 0xFFFF if unknown */
UWORD dpb_xbackupsec; /* backup boot sector number */
/* 0xFFFF if unknown */
ULONG dpb_xdata;
ULONG dpb_xsize; /* # of clusters+1 on media */
ULONG dpb_xfatsize; /* # of sectors / FAT */
ULONG dpb_xrootclst; /* starting cluster of root dir */
ULONG dpb_xcluster; /* cluster # of first free */
/* -1 if not known */
#endif
};
#define UNKNCLUSTER 0x0000 /* see RBIL INT 21/AH=52 entry */
#define XUNKNCLSTFREE 0xffffffffl /* unknown for DOS */
#define UNKNCLSTFREE 0xffff /* unknown for DOS */