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mirror.cpp
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mirror.cpp
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/*
// Program: Mirror
// Written By: Brian E. Reifsnyder
// Version: 0.2
// Copyright: 1999 under the terms of the GNU GPL
*/
#define NAME "Mirror"
#define VERSION "0.2"
/*
/////////////////////////////////////////////////////////////////////////////
// INCLUDES
/////////////////////////////////////////////////////////////////////////////
*/
#include <bios.h>
#include <dos.h>
#include <string.h>
#include <stdio.h>
#include <stdlib.h>
/*
/////////////////////////////////////////////////////////////////////////////
// DEFINES
/////////////////////////////////////////////////////////////////////////////
*/
#define TRUE 1
#define FALSE 0
#define NULL 0
#define PERCENTAGE 1
#define PRIMARY 0
#define EXTENDED 1
#define HARD 0
#define FLOPPY 1
#define FAT12 0
#define FAT16 1
#define FAT32 2
#define FIND 1
#define CREATE 2
#define FORCE 5
/*
/////////////////////////////////////////////////////////////////////////////
// GLOBAL VARIABLES
/////////////////////////////////////////////////////////////////////////////
*/
unsigned char *sector_buffer;
/* Physical Drive Parameters */
int physical_drive;
int logical_drive;
unsigned long logical_sector_offset;
long total_cylinders;
long total_heads;
long total_sectors;
long floppy_drive_type;
int drive_type;
int media_descriptor;
/* Logical drive information */
int bad_boot_sector=FALSE;
unsigned long sectors_per_cluster;
long sectors_per_fat;
long sectors_in_root_dir;
int type_of_fat;
unsigned long number_of_logical_sectors_on_drive;
long number_of_root_directory_entries;
/* Extracted cylinder & sector from partition table */
unsigned long g_cylinder;
unsigned long g_sector;
/* Partition Information */
int numeric_partition_type[24];
unsigned long starting_cylinder[24];
unsigned long starting_head[24];
unsigned long starting_sector[24];
unsigned long ending_cylinder[24];
unsigned long ending_head[24];
unsigned long ending_sector[24];
int relative_sectors_1[24];
int relative_sectors_2[24];
int relative_sectors_3[24];
int relative_sectors_4[24];
int partition_size_1[24];
int partition_size_2[24];
int partition_size_3[24];
int partition_size_4[24];
unsigned long partition_size[24];
int number_of_partitions;
unsigned long partition_table_cylinders[8][24];
unsigned int partition_table_heads[8][24];
unsigned int partition_table_sectors[8][24];
int partition_table_number_of_partitions[8];
int hard_drive_index;
int hard_disk_installed[8];
int store_partition_table_flag=FALSE;
/* "Logical Drive to Format" translation information */
int physical_drive_number;
unsigned long partition_starting_cylinder;
unsigned long partition_starting_head;
unsigned long partition_starting_sector;
unsigned long partition_ending_cylinder;
unsigned long partition_ending_head;
unsigned long partition_ending_sector;
unsigned long drive_maximum_cylinders;
unsigned long drive_maximum_heads;
unsigned long drive_maximum_sectors;
unsigned long total_logical_sectors;
unsigned long total_physical_sectors;
int number_of_sectors_per_cluster;
int partition_on_hard_disk;
/* Translated values from "void Convert_Logical_To_Physical" */
unsigned long translated_head;
unsigned long translated_cylinder;
unsigned long translated_sector;
/* Misc variables */
unsigned long integer1;
unsigned long integer2;
unsigned long integer3;
unsigned long integer4;
unsigned long beginning_of_mirror_image;
/* Buffers */
unsigned char *mirror_map;
unsigned char *mirror_buffer;
/*
/////////////////////////////////////////////////////////////////////////////
// PROTOTYPES
/////////////////////////////////////////////////////////////////////////////
*/
unsigned long Decimal_Number(unsigned long hex1, unsigned long hex2, unsigned long hex3, unsigned long hex4);
void Allocate_Buffers();
void Clear_Sector_Buffer();
void Convert_Huge_To_Integers(unsigned long number);
void Convert_Logical_To_Physical(unsigned long sector);
void Deallocate_Buffers();
void Display_Help_Screen();
void Display_Invalid_Combination();
void Extract_Cylinder_and_Sector(unsigned long hex1, unsigned long hex2);
void Get_Drive_Parameters();
void Get_Physical_Floppy_Drive_Parameters();
void Get_Physical_Hard_Drive_Parameters();
void Read_Boot_Sector();
void Read_Partition_Table();
void Read_Physical_Sector(int drive, int head, long cyl, int sector);
void Read_Sector(unsigned long sector);
void Reset_Drive();
void Save_File_System();
void Save_Partition_Tables();
void Write_Physical_Sector(int drive, int head, long cyl, int sector);
void Write_Sector(unsigned long sector);
/*
/////////////////////////////////////////////////////////////////////////////
// FUNCTIONS
/////////////////////////////////////////////////////////////////////////////
*/
/* Allocate Buffers */
void Allocate_Buffers()
{
mirror_buffer=(unsigned char *)malloc(32768);
mirror_map=(unsigned char *)malloc(5121);
sector_buffer=(unsigned char *)malloc(512);
if( (mirror_buffer==NULL) || (mirror_map==NULL) || (sector_buffer==NULL) )
{
printf("\nBuffer Allocation Failure...Program Terminated.\n");
Deallocate_Buffers();
exit(1);
}
}
/* Clear Sector Buffer */
void Clear_Sector_Buffer()
{
long loop=0;
do
{
sector_buffer[loop]=0;
loop++;
}while(loop<512);
}
/* Convert a logical sector to a physical drive location */
void Convert_Logical_To_Physical(unsigned long sector)
{
unsigned long remaining;
if(drive_type==HARD) sector=sector+logical_sector_offset;
translated_cylinder=sector/(total_sectors*(total_heads+1));
remaining=sector % (total_sectors*(total_heads+1));
translated_head=remaining/(total_sectors);
translated_sector=remaining % (total_sectors);
translated_sector++;
}
/* Convert Hexidecimal Number to a Decimal Number */
unsigned long Decimal_Number(unsigned long hex1, unsigned long hex2, unsigned long hex3, unsigned long hex4)
{
return((hex1) + (hex2*256) + (hex3*65536) + (hex4*16777216));
}
/* Convert Huge number into 4 LMB integer values */
void Convert_Huge_To_Integers(unsigned long number)
{
unsigned long temp=number;
unsigned long mask=0x000000ff;
integer1=temp & mask;
temp=number;
mask=0x0000ff00;
integer2=(temp & mask) >> 8;
temp=number;
mask=0x00ff0000;
integer3=(temp & mask) >> 16;
temp=number;
mask=0xff000000;
integer4=(temp & mask) >> 24;
}
void Deallocate_Buffers()
{
free(mirror_map);
free(sector_buffer);
free(mirror_buffer);
}
/* Extract Cylinder & Sector */
void Extract_Cylinder_and_Sector(unsigned long hex1, unsigned long hex2)
{
unsigned long cylinder_and_sector = ( (256*hex2) + hex1 );
g_sector = cylinder_and_sector % 64;
g_cylinder = ( ( (cylinder_and_sector*4) & 768) + (cylinder_and_sector /256) );
}
/* Help Routine */
void Display_Help_Screen()
{
printf("\n%6s Version %s\n\n",NAME,VERSION);
printf("Syntax:\n\n");
printf("MIRROR [drive:]\n");
printf("MIRROR [/PARTN]\n");
printf("\n");
printf(" drive: Saves UNFORMAT information to drive#.\n");
printf(" /PARTN Saves the partition tables to a:partnsav.fil for future\n");
printf(" recovery via UNFORMAT /PARTN.\n");
printf("\n\n\n\n\n");
}
void Display_Invalid_Combination()
{
printf("\nInvalid combination of options...please consult documentation.\n");
printf("Operation Terminated.\n");
Deallocate_Buffers();
exit(4);
}
/* Get Drive Parameters */
/* The physical drive parameters are necessary to allow this program */
/* to bypass the DOS interrupts. */
void Get_Drive_Parameters()
{
int drives_found_flag;
int increment_heads=FALSE;
int logical_drive_found=FALSE;
int partition_number_of_logical_drive;
int pointer=0;
int possible_logical_drive;
int possible_physical_hard_disk;
int sub_pointer=0;
int result;
/* Brief partition table variables */
long partition_type_table[8][26];
long maximum_partition_assigned[8];
if(drive_type==FLOPPY)
{
physical_drive=logical_drive;
Get_Physical_Floppy_Drive_Parameters();
partition_starting_cylinder=0;
partition_starting_head=0;
partition_starting_sector=1;
partition_ending_cylinder=total_cylinders;
partition_ending_head=total_heads;
partition_ending_sector=total_sectors;
drive_maximum_cylinders=total_cylinders;
drive_maximum_heads=total_heads;
drive_maximum_sectors=total_sectors;
total_logical_sectors=(total_cylinders+1)*(total_heads+1)*total_sectors;
total_physical_sectors=total_logical_sectors;
number_of_sectors_per_cluster=1;
}
else
{
/* Get availability of physical hard drives and */
/* assemble a brief partition table. */
/* Initialize partition_type_table */
pointer=0;
do
{
partition_type_table[0][pointer]=0;
partition_type_table[1][pointer]=0;
partition_type_table[2][pointer]=0;
partition_type_table[3][pointer]=0;
partition_type_table[4][pointer]=0;
partition_type_table[5][pointer]=0;
partition_type_table[6][pointer]=0;
partition_type_table[7][pointer]=0;
pointer++;
}while(pointer<=26);
/* Initialize maximum_partition_assigned */
maximum_partition_assigned[0]=0;
maximum_partition_assigned[1]=0;
maximum_partition_assigned[2]=0;
maximum_partition_assigned[3]=0;
maximum_partition_assigned[4]=0;
maximum_partition_assigned[5]=0;
maximum_partition_assigned[6]=0;
maximum_partition_assigned[7]=0;
pointer=128;
drives_found_flag=FALSE;
do
{
result=biosdisk(2, pointer, 0, 0, 1, 1, sector_buffer);
if(result==0)
{
drives_found_flag=TRUE;
hard_disk_installed[pointer-128]=TRUE;
physical_drive=pointer;
Read_Partition_Table();
sub_pointer=0;
do
{
partition_type_table[pointer-128][sub_pointer]=numeric_partition_type[sub_pointer];
sub_pointer++;
}while(sub_pointer<=number_of_partitions);
maximum_partition_assigned[pointer-128]=number_of_partitions;
}
else hard_disk_installed[pointer-128]=FALSE;
pointer++;
}while(pointer<136);
/* If there aren't any physical hard drives available, exit program */
if(drives_found_flag==FALSE)
{
printf("\nNo hard disks found...operation terminated.\n");
Deallocate_Buffers();
exit(4);
}
/* Determine on which physical hard drive the logical drive is */
/* and on which partition it is located. */
/* Check on primary partitions */
possible_logical_drive=1;
possible_physical_hard_disk=128;
do
{
if(hard_disk_installed[possible_physical_hard_disk-128]==TRUE)
{
pointer=0;
do
{
if( (partition_type_table[possible_physical_hard_disk-128][pointer]==0x01) || (partition_type_table[possible_physical_hard_disk-128][pointer]==0x04) || (partition_type_table[possible_physical_hard_disk-128][pointer]==0x06) )
{
possible_logical_drive++;
if(logical_drive==possible_logical_drive)
{
physical_drive=possible_physical_hard_disk;
partition_number_of_logical_drive=pointer;
logical_drive_found=TRUE;
}
}
pointer++;
}while(pointer<4);
}
possible_physical_hard_disk++;
}while(possible_physical_hard_disk<136);
/* Check on extended partitions */
possible_physical_hard_disk=128;
if(logical_drive_found==FALSE)
{
do
{
if( (hard_disk_installed[possible_physical_hard_disk-128]==TRUE) && (maximum_partition_assigned[possible_physical_hard_disk-128]>=4) )
{
pointer=4;
do
{
if( (partition_type_table[possible_physical_hard_disk-128][pointer]==0x01) || (partition_type_table[possible_physical_hard_disk-128][pointer]==0x04) || (partition_type_table[possible_physical_hard_disk-128][pointer]==0x06) )
{
possible_logical_drive++;
if(logical_drive==possible_logical_drive)
{
physical_drive=possible_physical_hard_disk;
partition_number_of_logical_drive=pointer;
increment_heads=TRUE;
logical_drive_found=TRUE;
}
}
pointer++;
}while(pointer<=maximum_partition_assigned[possible_physical_hard_disk-128]);
}
possible_physical_hard_disk++;
}while(possible_physical_hard_disk<136);
}
/* Get a full partition table listing for that drive */
if(logical_drive_found==TRUE)
{
Get_Physical_Hard_Drive_Parameters();
Read_Partition_Table();
}
else
{
printf("\nDrive letter entered is out of range...operation terminated.\n");
Deallocate_Buffers();
exit(4);
}
/* Load physical partition information */
partition_starting_cylinder=starting_cylinder[partition_number_of_logical_drive];
partition_starting_head=starting_head[partition_number_of_logical_drive];
partition_starting_sector=starting_sector[partition_number_of_logical_drive];
partition_ending_cylinder=ending_cylinder[partition_number_of_logical_drive];
partition_ending_head=ending_head[partition_number_of_logical_drive];
partition_ending_sector=ending_sector[partition_number_of_logical_drive];
drive_maximum_cylinders=ending_cylinder[partition_number_of_logical_drive];
drive_maximum_heads=total_heads;
drive_maximum_sectors=total_sectors;
total_logical_sectors=((partition_ending_cylinder-partition_starting_cylinder)+1)*(total_heads+1)*total_sectors;
total_physical_sectors=total_logical_sectors;
logical_sector_offset=((partition_starting_cylinder)*(total_heads+1)*(total_sectors));
if(logical_sector_offset==0) logical_sector_offset=(partition_starting_head)*(total_sectors);
if(increment_heads==TRUE) logical_sector_offset=logical_sector_offset+total_sectors;
/* Compute cluster size */
unsigned long size=(total_logical_sectors*512)/1000000;
/* Sectors per cluster conversion table */
if (size<=32767) number_of_sectors_per_cluster=64;
if (size<=16383) number_of_sectors_per_cluster=32;
if (size<=8191) number_of_sectors_per_cluster=16;
/* May be illegal cluster sizes
if (size<=256) number_of_sectors_per_cluster=8;
if (size<=128) number_of_sectors_per_cluster=4;
*/
}
}
/* Get Physical Floppy Drive Parameters */
void Get_Physical_Floppy_Drive_Parameters()
{
asm{
mov ah, 0x08
mov dl, BYTE PTR physical_drive
int 0x013
mov BYTE PTR total_sectors, cl
mov BYTE PTR total_cylinders, ch
mov BYTE PTR total_heads, dh
mov BYTE PTR floppy_drive_type, bl
}
}
/* Get Physical Hard Drive Parameters */
void Get_Physical_Hard_Drive_Parameters()
{
asm{
mov ah, 0x08
mov dl, BYTE PTR physical_drive
int 0x13
mov bl,cl
and bl,00111111B
mov BYTE PTR total_sectors, bl
mov bl,cl
mov cl,ch
shr bl,1
shr bl,1
shr bl,1
shr bl,1
shr bl,1
shr bl,1
mov ch,bl
mov WORD PTR total_cylinders, cx
mov BYTE PTR total_heads, dh
}
}
/* Read Boot Sector /////////////////// */
void Read_Boot_Sector()
{
long fat_16_total_sectors;
long fat_12_total_sectors;
Read_Sector(0);
sectors_per_fat = sector_buffer[22];
fat_16_total_sectors=Decimal_Number(sector_buffer[32],sector_buffer[33],sector_buffer[34],sector_buffer[35]);
fat_12_total_sectors=Decimal_Number(sector_buffer[19],sector_buffer[20],0,0);
number_of_root_directory_entries=Decimal_Number(sector_buffer[17],sector_buffer[18],0,0);
if(fat_16_total_sectors==0)
{
type_of_fat=FAT12;
number_of_logical_sectors_on_drive=fat_12_total_sectors;
}
else
{
type_of_fat=FAT16;
number_of_logical_sectors_on_drive=fat_16_total_sectors;
}
if( (fat_12_total_sectors>0) && (fat_16_total_sectors>0) ) bad_boot_sector=TRUE;
sectors_per_cluster=Decimal_Number(sector_buffer[13],0,0,0);
}
/* Read Partition Table */
void Read_Partition_Table()
{
long index=0x1be;
int exiting_primary=TRUE;
int extended=FALSE;
int partition_designation=PRIMARY;
int pointer=0;
int record_extended_info_flag=FALSE;
int done_flag=FALSE;
int store_partition_counter=0;
unsigned long extended_cylinder;
unsigned long extended_head;
unsigned long extended_sector;
Read_Physical_Sector(physical_drive,0,0,1);
if(store_partition_table_flag==TRUE)
{
partition_table_cylinders[hard_drive_index][store_partition_counter]=0;
partition_table_heads[hard_drive_index][store_partition_counter]=0;
partition_table_sectors[hard_drive_index][store_partition_counter]=1;
partition_table_number_of_partitions[hard_drive_index]=store_partition_counter;
store_partition_counter++;
}
do{
if(pointer==4) partition_designation=EXTENDED;
if((pointer>=4) && (extended==TRUE))
{
Read_Physical_Sector(physical_drive,extended_head,extended_cylinder,extended_sector);
if(store_partition_table_flag==TRUE)
{
partition_table_cylinders[hard_drive_index][store_partition_counter]=extended_cylinder;
partition_table_heads[hard_drive_index][store_partition_counter]=extended_head;
partition_table_sectors[hard_drive_index][store_partition_counter]=extended_sector;
partition_table_number_of_partitions[hard_drive_index]=store_partition_counter;
store_partition_counter++;
}
extended=FALSE;
index=0x1be;
if(exiting_primary==FALSE)
{
pointer--;
}
else
{
exiting_primary=FALSE;
}
}
/* Determine Partition Type */
numeric_partition_type[pointer]=sector_buffer[index+4];
if(sector_buffer[index+4]==0x00)
{
if(partition_designation==EXTENDED)
{
number_of_partitions=pointer;
done_flag=TRUE;
}
}
if(sector_buffer[index+4]==0x05)
{
extended=TRUE;
record_extended_info_flag=TRUE;
}
starting_head[pointer] = sector_buffer[index+1];
ending_head[pointer] = sector_buffer[index+5];
partition_size[pointer]=Decimal_Number(sector_buffer[index+12],sector_buffer[index+13],sector_buffer[index+14],sector_buffer[index+15])/2000;
Extract_Cylinder_and_Sector(sector_buffer[index+2],sector_buffer[index+3]);
starting_cylinder[pointer]=g_cylinder;
starting_sector[pointer]=g_sector;
if((extended==TRUE) && (record_extended_info_flag==TRUE))
{
extended_cylinder=starting_cylinder[pointer];
extended_head=starting_head[pointer];
extended_sector=starting_sector[pointer];
record_extended_info_flag=FALSE;
}
Extract_Cylinder_and_Sector(sector_buffer[index+6],sector_buffer[index+7]);
ending_cylinder[pointer]=g_cylinder;
ending_sector[pointer]=g_sector;
partition_size_1[pointer]=sector_buffer[index+12];
partition_size_2[pointer]=sector_buffer[index+13];
partition_size_3[pointer]=sector_buffer[index+14];
partition_size_4[pointer]=sector_buffer[index+15];
relative_sectors_1[pointer]=sector_buffer[index+8];
relative_sectors_2[pointer]=sector_buffer[index+9];
relative_sectors_3[pointer]=sector_buffer[index+10];
relative_sectors_4[pointer]=sector_buffer[index+11];
pointer++;
number_of_partitions=pointer-1;
if((extended==FALSE) && (pointer==4))
{
number_of_partitions=4;
done_flag=TRUE;
}
index=index + 16;
} while(done_flag==FALSE);
}
/* Read Physical Sector */
void Read_Physical_Sector(int drive, int head, long cyl, int sector)
{
int result;
result=biosdisk(2, drive, head, cyl, sector, 1, sector_buffer);
if (result!=0)
{
printf("\nRead error...operation terminated.\n");
Deallocate_Buffers();
exit(4);
}
}
/* Read Sector From Disk */
void Read_Sector(unsigned long sector)
{
Convert_Logical_To_Physical(sector);
Read_Physical_Sector(physical_drive,translated_head,translated_cylinder,translated_sector);
}
/* Reset drive controller */
void Reset_Drive()
{
asm{
mov ah,0
mov dl,BYTE PTR physical_drive
int 0x13
mov ah,0
mov dl,BYTE PTR physical_drive
int 0x13
}
}
/* Save the old file system for possible recovery with unformat */
void Save_File_System()
{
int end_of_root_directory_flag;
long loop=512;
unsigned long pointer=0;
unsigned long offset_from_end=5;
unsigned long destination_sector;
unsigned long source_sector;
unsigned long mirror_beginning;
unsigned long mirror_map_beginning;
unsigned long mirror_map_size;
unsigned long mirror_size;
unsigned long number_of_bytes_in_mirror_map;
unsigned long beginning_of_fat;
unsigned long beginning_of_root_directory;
unsigned long end_of_fat;
unsigned long end_of_root_directory;
unsigned long cluster;
unsigned long remainder;
unsigned long fat_table_1_start_sector;
unsigned long fat_table_2_start_sector;
unsigned long total_clusters;
unsigned long fat_table_offset_sector;
unsigned int sector_flag[] = {
'A','M','S','E','S','L','I','F','V','A','S',
'R','O','R','I','M','E','S','A','E','P'};
unsigned int mirror_map_header[] = {
':','\\','M','I','R','R','O','R','.','F','I','L'};
if(drive_type==HARD) offset_from_end=20;
/* Get the boot sector, compute the FAT size, compute the root dir size,*/
/* and get the end of the logical drive. */
Read_Boot_Sector();
printf("\n\nSaving UNFORMAT information...\n");
/* Compute the beginning sector of the mirror map and the size of */
/* the mirror image. */
mirror_size=1+sectors_per_fat+66;
mirror_map_size=(mirror_size/64)+2;
mirror_beginning=(number_of_logical_sectors_on_drive-mirror_size)-offset_from_end;
mirror_map_beginning=mirror_beginning-mirror_map_size;
/* Compute the locations of the first FAT and the root directory */
beginning_of_fat=1;
end_of_fat=beginning_of_fat+sectors_per_fat-1;
beginning_of_root_directory=(beginning_of_fat+sectors_per_fat-1)*2;
end_of_root_directory=beginning_of_root_directory+(number_of_root_directory_entries/32);
/* Reserve space in FAT tables so that the */
/* mirror image is never overwritten */
fat_table_1_start_sector=1;
fat_table_2_start_sector=fat_table_1_start_sector+sectors_per_fat;
cluster=mirror_map_beginning/sectors_per_cluster;
total_clusters=number_of_logical_sectors_on_drive/sectors_per_cluster;
/* FAT16 has 256 entries per sector */
/* FAT12 has 384 entries per sector */
do
{
if(type_of_fat==FAT12)
{
printf("\nFAT 12 file systems are not supported at this time.\n");
Deallocate_Buffers();
exit(6);
}
if(type_of_fat==FAT16)
{
fat_table_offset_sector=(cluster+2)/256;
remainder=((cluster+2) % 256);
Read_Sector(fat_table_offset_sector+fat_table_1_start_sector);
sector_buffer[(remainder*2)]=0xff;
sector_buffer[(remainder*2)+1]=0xf6;
Write_Sector(fat_table_offset_sector+fat_table_1_start_sector);
Write_Sector(fat_table_offset_sector+fat_table_2_start_sector);
}
if(type_of_fat==FAT32)
{
printf("\nFAT 32 file systems are not supported at this time.\n");
Deallocate_Buffers();
exit(6);
}
printf("%u\n",cluster);
cluster++;
}while(cluster<=total_clusters);
/* Clear the last sectors of a hard disk */
/* to ensure that UNFORMAT does not get confused. */
pointer=mirror_map_beginning;
Clear_Sector_Buffer();
do
{
Write_Sector(pointer);
pointer++;
}while(pointer<number_of_logical_sectors_on_drive);
/* Write the mirror map pointer to the last sectors of the logical drive. */
Clear_Sector_Buffer();
Convert_Huge_To_Integers(mirror_map_beginning);
sector_buffer[0]=integer1;
sector_buffer[1]=integer2;
sector_buffer[2]=integer3;
sector_buffer[3]=integer4;
pointer=4;
do /* Add pointer sector flag */
{
sector_buffer[pointer]=sector_flag[pointer-4];
pointer++;
}while(pointer<=24);
Write_Sector(number_of_logical_sectors_on_drive-offset_from_end);
/* Create the mirror map and copy the file system to the mirror. */
Clear_Sector_Buffer();
pointer=0;
do /* Clear mirror_map buffer */
{
mirror_map[pointer]=0;
pointer++;
}while(pointer<=5120);
mirror_map[0]=logical_drive+65;
pointer=1;
do /* Add mirror map header */
{
mirror_map[pointer]=mirror_map_header[pointer-1];
pointer++;
}while(pointer<=12);
/* Main mirror map creation */
/* and copying loop. */
pointer=84;
source_sector=0;
destination_sector=mirror_beginning;
end_of_root_directory_flag=FALSE;
number_of_bytes_in_mirror_map=0;
do
{
if( (source_sector!=0) && (source_sector<beginning_of_fat) ) source_sector=beginning_of_fat;
if( (source_sector>end_of_fat) && (source_sector<beginning_of_root_directory) ) source_sector=beginning_of_root_directory;
/* Copy mirror image one sector at a time */
Read_Sector(source_sector);
Write_Sector(destination_sector);
/* Enter mapping information into mirror map buffer */
Convert_Huge_To_Integers(source_sector);
mirror_map[pointer+0]=integer1;
mirror_map[pointer+1]=integer2;
mirror_map[pointer+2]=integer3;
mirror_map[pointer+3]=integer4;
Convert_Huge_To_Integers(destination_sector);
mirror_map[pointer+4]=integer1;
mirror_map[pointer+5]=integer2;
mirror_map[pointer+6]=integer3;
mirror_map[pointer+7]=integer4;
source_sector++;
destination_sector++;
pointer=pointer+8;
number_of_bytes_in_mirror_map=pointer;
if(source_sector>end_of_root_directory) end_of_root_directory_flag=TRUE;
}while(end_of_root_directory_flag==FALSE);
/* Write trailer in mirror map */
mirror_map[pointer+0]=0;
mirror_map[pointer+1]=0;
mirror_map[pointer+2]=0;
mirror_map[pointer+3]=0;
/* Write the mirror map onto the disk. */
pointer=0;
destination_sector=mirror_map_beginning;
do
{
loop=0;
do /* Load the sector buffer */
{
sector_buffer[loop]=mirror_map[pointer+loop];
loop++;
}while(loop<512);
Write_Sector(destination_sector); /* Write the mirror map */
/* sector. */
destination_sector++;
pointer=pointer+512;
}while(pointer < number_of_bytes_in_mirror_map);
}
/* Save the partition tables to a floppy disk */
void Save_Partition_Tables()
{
/*
Map of the PARTNSAV.FIL for FreeDOS:
(I do not plan on using an MS-DOS compatible file.)