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#include "dos.h" /* AN000 */
#include "fdisk.h" /* AN000 */
#include "extern.h" /* AN000 */
#include "subtype.h" /* AN000 */
#include "fdiskmsg.h" /* AN000 */
#include "string.h"
#include "stdio.h"
#include "stdlib.h"
/* int printf(char *, ...); */
/* */
char get_disk_info()
BEGIN
unsigned char i;
/* Initialize values */
number_of_drives = uc(0); /* AC000 */
for (i=uc(0); i < uc(2); i++) /* AC000 */
BEGIN
total_disk[i] = u(0); /* AC000 */
total_mbytes[i] = f(0); /* AC000 */
max_sector[i] = uc(0); /* AC000 */
max_head[0] = u(0); /* AC004 */
END
/* See how many drives there are */
if (get_drive_parameters(uc(0x80))) /* AC000 */
BEGIN
/* Get the drive parameters for all drives */
for (i = uc(0); i < number_of_drives;i++) /* AC000 */
BEGIN
if (get_drive_parameters(uc(0x80)+i)) /* AC000 */
BEGIN
/* Save drive parameters */
max_sector[i] = ((unsigned char)(regs.h.cl & 0x3F));
max_head[i] = ((unsigned)(regs.h.dh +1)); /* AC004 */
#if IBMCOPYRIGHT
total_disk[i] = ((((unsigned)(regs.h.cl & 0xC0 )) & 0x00C0) << 2)+ ((unsigned)regs.h.ch) +1;
#else
total_disk[i] = ((((unsigned)(regs.h.cl & 0xc0)) << 2) | regs.h.ch) + 1;
#endif
total_mbytes[i] = cylinders_to_mbytes(total_disk[i],i); /* AN004 */
END
else
BEGIN
good_disk[i] = FALSE;
return(FALSE);
END
END
return(TRUE);
END
else
/* No drives present */
BEGIN
no_fatal_error = FALSE;
return(FALSE);
END
END
/* */
char write_boot_record(cylinder,which_disk)
unsigned cylinder;
unsigned char which_disk;
BEGIN
char i;
char j;
char far *buffer_pointer = boot_record;
/* Setup read, always on a cylinder boundary */
regs.h.ah = uc(WRITE_DISK); /* AC000 */
regs.h.al = uc(1); /* AC000 */
regs.h.dh = uc(0); /* AC000 */
regs.h.cl = uc(0x01); /* AC000 */
/* Specify the disk */
regs.h.dl = which_disk + 0x80;
/* Need to scramble CX so that sectors and cyl's are in INT 13 format */
if (cylinder > u(255)) /* AC000 */
BEGIN
regs.h.cl = regs.h.cl | ((unsigned char)((cylinder /256) << 6));
END
regs.h.ch = (unsigned char)(cylinder & 0xFF);
/* Point at the place to read the boot record */
regs.x.bx = FP_OFF(buffer_pointer);
segregs.es = FP_SEG(buffer_pointer);
/* write the boot record */
DiskIo(®s,®s,&segregs); /* AC000 */
/* Check for error reading it */
if ((regs.x.cflag & 1) != u(1)) /* AC000 */
BEGIN
return(TRUE);
END
else
BEGIN
/* Tell user there was an error */
clear_screen(u(0),u(0),u(24),u(79)); /* AC000 */
display(error_2);
no_fatal_error = FALSE;
return(FALSE);
END
END
/* */
unsigned verify_tracks(pointer,type)
char pointer;
char type;
BEGIN
unsigned i;
unsigned location;
unsigned sectors_per_fat;
unsigned cur_cyl;
unsigned verify_cyl;
unsigned num_tracks;
unsigned long total_sectors;
char golden_tracks;
char retry;
unsigned char cur_head; /* AC004 */
char far *buffer_pointer = boot_record;
char head;
for (i=u(0); i< u(BYTES_PER_SECTOR);i++) /* AC000 */
BEGIN
/* Put something other then 0's so that unformatted FAT looks full */
boot_record[i] = uc(0xF6); /* AC000 */
END
/* Get the start cylinder for the sweep */
cur_cyl = free_space[pointer].start;
/* Also keep track of what it is */
verify_cyl = cur_cyl;
/* Initialize the start head -assume 0*/
cur_head = uc(0); /* AC004 */
if ((type == c(PRIMARY)) && (cur_cyl == u(0))) /* AC000 */
BEGIN
/* It's head 1 - NOTE: This is convience for PC-DOS because it is */
/* always this way - This may have to be beefed up for IFS */
cur_head = uc(1); /* AC004 */
END
/* Now go figure out the number of golden sectors needed. Use the */
/* allocation equation in the fixed disk section of DOS Tech Ref. */
/* */
/* TS = Free cyl's * sector/track * track/cyl */
/* RS = 1 */
/* D = 512 */
/* BPD = 32 */
/* BPS = BYTES_PER_SECTOR */
/* CF = 2 */
/* SPF = Solve */
/* SPC = 4 or 8 */
/* BPC = 1.5 or 2 */
/* */
/* Golden Sectors = RS + 2(SPF) + BPD(D) + (DOSFILES) */
/* ������ if bootable */
/* BPS */
total_sectors = ((unsigned long)free_space[pointer].space) * max_head[cur_disk] * max_sector[cur_disk];
/* Chop off one track if it starts on head 1 */
if (cur_head == uc(1)) /* AC004 */
BEGIN
total_sectors = total_sectors - max_sector[cur_disk];
END
/* See if 12 or 16 bit fat */
if (total_sectors > (unsigned long)FAT16_SIZE)
BEGIN
/* 16 bit */
sectors_per_fat = ((unsigned)((total_sectors -33)/(2 + ((BYTES_PER_SECTOR *4)/2))));
END
else
BEGIN
/* 12 bit */
sectors_per_fat = ((unsigned)((total_sectors -33)/(2 + ((BYTES_PER_SECTOR *8)/1.5))));
END
/* Round up one just to handle any rounding errors */
sectors_per_fat++;
/* Now see how many tracks */
num_tracks = (sectors_per_fat*2) + 33;
/* If primary and drive 0, add in enough for system files */
if ((type == c(PRIMARY)) && (cur_disk == c(0))) /* AC000 */
BEGIN
num_tracks = num_tracks + SYSTEM_FILE_SECTORS;
END
#if IBMCOPYRIGHT
/* Now convert to tracks */
num_tracks = num_tracks/max_sector[cur_disk];
/* Handle upward rounding */
if (num_tracks%max_sector[cur_disk] != u(0)) /* AC000 */
BEGIN
num_tracks++;
END
#else
/* Handle upward rounding */ /* The problem with the IBM code is */
if (num_tracks%max_sector[cur_disk] != u(0)) /* that if num_tracks is < max_sector[cur_disk] */
BEGIN /* the num_tracks becomes 0 due to the integer */
num_tracks = num_tracks + max_sector[cur_disk]; /* division and num_tracks will not be inc'd . */
END /* This section of code overcomes that. */
/* Now convert to tracks */
num_tracks = num_tracks/max_sector[cur_disk];
#endif
golden_tracks = FALSE;
while (!golden_tracks)
BEGIN
for (i = u(0);i < num_tracks; i++) /* AC000 */
BEGIN
retry = c(0); /* AC000 */
do
BEGIN
retry++;
/* Specify the operation */
regs.h.ah = uc(WRITE_DISK); /* AC000 */
/* Specify number of sectors */
regs.h.al = ((unsigned char)max_sector[cur_disk]);
/* Specify the start sectors */
regs.h.cl = uc(1); /* AC000 */
/* Need to scramble CX so that sectors and cyl's are in INT 13 format */
if (cur_cyl > u(255)) /* AC000 */
BEGIN
regs.h.cl = regs.h.cl | ((unsigned char)((cur_cyl/256) << 6));
END
regs.h.ch = ((unsigned char)cur_cyl) & 0xFF;
/* Specify the disk */
regs.h.dl = ((unsigned char)cur_disk) + 0x80;
/* Specify the head */
regs.h.dh = cur_head; /* AC004 */
/* Point at the place to write */
regs.x.bx = FP_OFF(buffer_pointer);
segregs.es = FP_SEG(buffer_pointer);
/* write the track */
DiskIo(®s,®s,&segregs); /* AC000 */
END
while (((regs.x.cflag & 1) == u(1)) && (retry != c(5))); /* AC000 */
/* See if we had a good read */
if ((regs.x.cflag & 1) != u(1)) /* AC000 */
BEGIN
golden_tracks = TRUE;
/* Get the next head */
cur_head++;
if (cur_head == (uc(max_head[cur_disk] -1))) /* AC004 */
BEGIN
/* Up to the next cylinder */
cur_head = uc(0); /* AC004 */
cur_cyl++;
/* Check to see if we've reached the end of the free_space*/
if (cur_cyl > free_space[pointer].end)
BEGIN
/* It is, so return with the cyl offset equal to the freespace */
return(free_space[pointer].space);
END
END
END
else
BEGIN
/* Get out of the for loop, with a false flag */
golden_tracks = FALSE;
/* Bump up to the next cylinder boundary */
cur_cyl++;
cur_head = uc(0); /* AC004 */
/* Save the new verify start point */
verify_cyl = cur_cyl;
break;
END
END /* for num_tracks */
END /* while !golden_tracks */
/* All done, return the offset from original cyl to the new one */
return(verify_cyl - free_space[pointer].start);
END
/* */
char get_drive_parameters(drive)
unsigned char drive;
BEGIN
/* See how many drives there are */
regs.h.ah = uc(DISK_INFO); /* AC000 */
regs.h.dl = drive;
DiskIo(®s,®s,&segregs); /* AC000 */
/* See if any drives exist */
if ((regs.h.dl == uc(0)) || ((regs.x.cflag & 1) == u(1))) /* AC000 */
BEGIN
display(error_1);
return(FALSE);
END
else
BEGIN
/* Save the number of drives */
number_of_drives = regs.h.dl;
return(TRUE);
END
END
/* */
char read_boot_record(cylinder,which_disk,which_head,which_sector) /* AC000 */
unsigned cylinder;
unsigned char which_disk;
unsigned char which_head; /* AN000 */
unsigned char which_sector; /* AN000 */
BEGIN
char far *buffer_pointer = boot_record;
/* Setup read, always on a cylinder boundary */
regs.h.ah = uc(READ_DISK); /* AC000 */
regs.h.al = uc(1); /* AC000 */
regs.h.dh = which_head; /* AC000 */
regs.h.cl = which_sector; /* AC000 */
/* Specify the disk */
regs.h.dl = which_disk + 0x80;
/* Need to scramble CX so that sectors and cyl's are in INT 13 format */
if (cylinder > u(255)) /* AC000 */
BEGIN
regs.h.cl = regs.h.cl | ((char)((cylinder /256) << 6));
END
regs.h.ch = (unsigned char)(cylinder & 0xFF);
/* Point at the place to write the boot record */
regs.x.bx = FP_OFF(buffer_pointer);
segregs.es = FP_SEG(buffer_pointer);
/* read in the boot record */
DiskIo(®s,®s,&segregs); /* AC000 */
/* Check for error reading it */
if ((regs.x.cflag & 1) != u(1)) /* AC000 */
BEGIN
return(TRUE);
END
else
BEGIN
/* Tell user there was an error */
good_disk[which_disk] = FALSE;
clear_screen(u(0),u(0),u(24),u(79)); /* AC000 */
return(FALSE);
END
END
/* */
void DiskIo(InRegs,OutRegs,SegRegs)
union REGS *InRegs;
union REGS *OutRegs;
struct SREGS *SegRegs;
BEGIN
char *WritePtr;
#ifdef DEBUG
switch(InRegs->h.ah)
{
case 0:
case 1:
case 2:
case 4:
case 8:
case 15:
case 16:
int86x((int)DISK,InRegs,OutRegs,SegRegs); /* AC000 */
break;
default:
WritePtr = getenv("WRITE");
if (strcmpi(WritePtr,"ON") != 0)
BEGIN
printf("\nDisallowing Disk I/O Request\n");
printf("AX:%04X BX:%04X CX:%04X DX:%04X ES:%04X\n",
InRegs->x.ax,InRegs->x.bx,InRegs->x.cx,InRegs->x.dx,SegRegs->es);
OutRegs->h.ah = (unsigned char) 0;
OutRegs->x.cflag = (unsigned) 0;
END
else int86x((int)DISK,InRegs,OutRegs,SegRegs);
break;
}
#else
int86x((int)DISK,InRegs,OutRegs,SegRegs); /* AC000 */
#endif
return;
END
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