/*
FIPS - the First nondestructive Interactive Partition Splitting program
Module disk_io.cpp
RCS - Header:
$Header: c:/daten/fips/source/main/RCS/disk_io.cpp 1.4 1995/01/19 00:00:51 schaefer Exp schaefer $
Copyright (C) 1993 Arno Schaefer
This program 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 of the License, or
(at your option) any later version.
This program 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 this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
Report problems and direct all questions to:
[email protected]
*/
#include "disk_io.h"
#include <dos.h>
#include <bios.h>
#define DISK_INT 0x13
#define RESET_DISK 0
#define READ_SECTOR 2
#define WRITE_SECTOR 3
#define VERIFY_SECTOR 4
#define GET_DRIVE_PARAMS 8
#define GET_DISK_TYPE 0x15
/* ----------------------------------------------------------------------- */
/* Bios call to get the number of drives attached */
/* ----------------------------------------------------------------------- */
int get_no_of_drives (void)
{
union REGS regs;
regs.h.ah = GET_DRIVE_PARAMS;
regs.h.dl = 0x80;
int86 (DISK_INT, ®s, ®s);
if (regs.h.ah != 0) return (1); // will be checked again
return (regs.h.dl);
}
/* ----------------------------------------------------------------------- */
/* Calculates physical sector number (Head, Cylinder, Sector). */
/* Log_sector is absolute logical sector number (0 = master boot record). */
/* ----------------------------------------------------------------------- */
physical_sector_no::physical_sector_no
(
dword logical_sector,
const drive_geometry &geometry
)
{
cylinder =
logical_sector
/ (geometry.heads * geometry.sectors);
head =
(
logical_sector
- (cylinder * geometry.heads * geometry.sectors)
)
/ geometry.sectors;
sector =
logical_sector
- (cylinder * geometry.heads * geometry.sectors)
- (head * geometry.sectors)
+ 1;
}
/* ----------------------------------------------------------------------- */
/* Bios call get_drive_geometry, returns error status in var errorcode */
/* ----------------------------------------------------------------------- */
void physical_drive::get_geometry (void)
{
union REGS regs;
regs.h.ah = GET_DRIVE_PARAMS;
regs.h.dl = number;
int86 (DISK_INT, ®s, ®s);
if ((errorcode = regs.h.ah) != 0) return;
geometry.heads = (dword) regs.h.dh + 1;
geometry.sectors = (dword) regs.h.cl & 0x3f;
geometry.cylinders =
(
(dword) regs.h.ch
| (((dword) regs.h.cl << 2) & 0x300)
) + 1;
}
/* ----------------------------------------------------------------------- */
/* Bios call reset_drive, returns error status in var errorcode */
/* ----------------------------------------------------------------------- */
void physical_drive::reset (void)
{
union REGS regs;
regs.h.ah = RESET_DISK;
regs.h.dl = number;
int86 (DISK_INT, ®s, ®s);
errorcode = regs.h.ah;
}
/* ----------------------------------------------------------------------- */
/* Initialization physical_drive, requires drive number. */
/* Calls get_drive_geometry, errorcode contains return status */
/* ----------------------------------------------------------------------- */
physical_drive::physical_drive (int number)
{
physical_drive::number = number;
get_geometry ();
};
/* ----------------------------------------------------------------------- */
/* Initialization physical_drive with physical_drive object */
/* ----------------------------------------------------------------------- */
physical_drive::physical_drive (physical_drive &pd)
{
number = pd.number;
errorcode = pd.errorcode;
geometry = pd.geometry;
}
/* ----------------------------------------------------------------------- */
/* Assignment operator for physical drive */
/* ----------------------------------------------------------------------- */
void physical_drive::operator= (physical_drive &pd)
{
number = pd.number;
errorcode = pd.errorcode;
geometry = pd.geometry;
}
/* ----------------------------------------------------------------------- */
/* Read sector */
/* ----------------------------------------------------------------------- */
int physical_drive::read_sector (struct sector *sector, dword sector_number)
{
physical_sector_no p (sector_number, geometry);
boolean done = false;
for (int i=0; i<3; i++)
{
if (biosdisk
(
READ_SECTOR,
number,
p.head,
p.cylinder,
p.sector,
1,
sector->data
) == 0)
{
done=true;
break;
}
reset ();
}
if (!done) return (-1);
return 0;
}
/* ----------------------------------------------------------------------- */
/* Write sector with verify */
/* ----------------------------------------------------------------------- */
int physical_drive::write_sector (struct sector *sector, dword sector_number)
{
physical_sector_no p (sector_number,geometry);
boolean done = false;
for (int i=0; i<3; i++)
{
if (biosdisk
(
WRITE_SECTOR,
number,
p.head,
p.cylinder,
p.sector,
1,
sector->data
) == 0)
{
done=true;
break;
}
reset ();
}
if (!done) return (-1);
if (biosdisk
(
VERIFY_SECTOR,
number,
p.head,
p.cylinder,
p.sector,
1,
sector->data
) != 0) return (-1);
return 0;
}
/* ----------------------------------------------------------------------- */
/* Bios call get_disk_type - returns 0 if drive not present. */
/* Valid drive numbers: 0 - 255, result: 1 - floppy without disk change */
/* detection, 2 - floppy with disk change detection, 3 - harddisk */
/* ----------------------------------------------------------------------- */
int get_disk_type (int drive_number)
{
union REGS regs;
regs.h.ah = GET_DISK_TYPE;
regs.h.dl = drive_number;
int86 (DISK_INT, ®s, ®s);
if (regs.x.cflag) return 0;
return (regs.h.ah); // disk type
}
