Practic 01

// Practic1Lab1.cpp : Defines the entry point for the console application.
//

#include "stdafx.h"
// ossp01.cpp : This file contains the 'main' function. Program execution begins and ends there.
//

#include "pch.h"
struct BPB {
    WORD sectorSize;
    BYTE clusterSize;
    WORD reservedSectors;
    BYTE fatCount;
    WORD rootSize;
    WORD totalSectors;
    BYTE media;
    WORD fatSize;
    WORD sectors;
    WORD heads;
    WORD hiddenLow;
    WORD hiddenHigh;
    BYTE largeTotalSectors[4];
};

struct bootRecord {
    BYTE jmpCommand[3];
    BYTE vendorName[8];
    BPB extendedBlock;
    BYTE drivePhysicalNumber;
    BYTE rezerved;
    BYTE symbolBrackets;
    BYTE volumeSerialNumber[4];
    BYTE volumeLabel[11];
    BYTE identifierFAT[8];
    BYTE bootCode[450];
} boot;

typedef struct root_Entries
{
    BYTE short_FileName[11];
    BYTE fileAttributes;
    BYTE reserved;
    BYTE createTime_ms;
    WORD createTime;
    WORD createDate;
    WORD accessedDate;
    WORD clusterNumber_High;
    WORD modifiedTime;
    WORD modifiedDate;
    WORD firstClusterAddress_FAT12;
    DWORD sizeofFile;
} root;

void ScanBootSector();
void ScanRoot();
void ScanFat();

WORD FAT[2880];
BYTE Buffer[512 * 9];
WORD* Val;
HANDLE hDisk;

int main()
{
    hDisk = CreateFile(TEXT("C:\\Tmp\\Dos6.22.img"),    // drive to open
        GENERIC_READ,                     // Access mode
        FILE_SHARE_READ,                  // Share Mode
        NULL,                             // Security Descriptor
        OPEN_EXISTING,                    // How to create
        0,                                // File attributes
        NULL);                            // Handle to template
    if (hDisk != NULL)
    {
        ScanBootSector();
        ScanRoot();
        ScanFat();
        int cluster = 2619;
        int count = 1;
        while (FAT[cluster] != 0xfff)
        {
            printf("%6x\t", FAT[cluster]);
            cluster = FAT[cluster];
            count++;
        }
        printf("\n%d", count);
    }
    CloseHandle(hDisk);

    return 0;
}

void ScanFat() {
    DWORD dwBytesRead;
    WORD fatElement;
    int j = 0;
    SetFilePointer(hDisk, 512, NULL, FILE_BEGIN);
    ReadFile(hDisk, Buffer, 512 * 9, &dwBytesRead, NULL);
    if (Buffer[0] != boot.extendedBlock.media) {
        printf("Error 1 \n");
        return;
    }
    //FAT table entries are packed so that two cluster entries occupy three bytes with the following general format :
    //yz Zx XY
    //  where
    //  xyz is the one pointer entry and
    //  XYZ is the second pointer entry.
    //  E.g., bytes :
    //  2d e0 02
    //  refer to clusters 0x02d (45) and 0x02e (46)

    for (int i = 0, j = 0; i < 512 * 9; i += 3, j += 2) {
        FAT[j] = (Buffer[i] + (Buffer[i + 1] << 8)) & 0x0FFF;
        FAT[j+1] = (Buffer[i + 1] + (Buffer[i + 2] << 8)) >> 4;
    }
}

void ScanRoot() {
    DWORD dwFilePointer;
    DWORD dwBytesRead;
    root stRoot;
    BYTE byteRoot[512];
    memset(&byteRoot, 0, 512);
    dwFilePointer = SetFilePointer(hDisk, (512 * 19), NULL, FILE_BEGIN);
    if (dwFilePointer == INVALID_SET_FILE_POINTER && GetLastError() != NO_ERROR)
    {
        // Deal with failure
        // . . .

    } // End of error handler
    int iSector = 19;
    BOOL bNoEntry = FALSE;
    // Iterate through root directory sectors
    do
    {
        if (!ReadFile(hDisk, byteRoot, 512, &dwBytesRead, NULL))
        {
            printf("Error in Reading Root Entry.\n");
        }
        else
        {
            BYTE *pByteRoot = byteRoot;
            // Iterate through 32 byte entries
            for (int i = 0; i < (512 / 32); i++)
            {
                ZeroMemory(&stRoot, 32);
                memcpy(&stRoot, pByteRoot, 32);

                // No entry beyond this used.
                if (stRoot.short_FileName[0] == 0x00)
                {
                    // Stop iteration
                    bNoEntry = TRUE;
                    break;
                }
                else
                {
                    // This if loops checks for file deletion
                    // status
                    if (stRoot.short_FileName[0] == 0xE5)
                    {
                        printf("First character of file after deletion :0x%x\n",
                            stRoot.short_FileName[0]);
                        printf("File status: Deleted.\n");
                    }


                    puts("File Name            :");
                    for (size_t idx = 0; idx < 8; idx++)
                    {
                        putchar(stRoot.short_FileName[idx]);
                    }
                    putchar('\n');
                    if (stRoot.fileAttributes & 0x01)
                        printf("File Attribute       : Read Only File\n");
                    if (stRoot.fileAttributes & 0x02)
                        printf("File Attribute    : Hidden File\n");
                    if (stRoot.fileAttributes & 0x04)
                        printf("File Attribute    : System File\n");
                    if (stRoot.fileAttributes & 0x08)
                        printf("File Attribute    : Volume Label\n");
                    if (stRoot.fileAttributes & 0x0f)
                        printf("File Attribute    : Long File Name\n");
                    if (stRoot.fileAttributes & 0x10)
                        printf("File Attribute    : Directory\n");
                    if (stRoot.fileAttributes & 0x20)
                        printf("File Attribute    : Archive\n");

                    WORD nYear = (stRoot.createDate >> 9);
                    WORD nMonth = (stRoot.createDate << 7);
                    nMonth = nMonth >> 12;
                    WORD nDay = (stRoot.createDate << 11);
                    nDay = nDay >> 11;

                    //printf("Create Date    : %d/%d/%d\n", nDay, nMonth, (nYear + 1980));

                    nYear = (stRoot.modifiedDate >> 9);
                    nMonth = (stRoot.modifiedDate << 7);
                    nMonth = nMonth >> 12;
                    nDay = (stRoot.modifiedDate << 11);
                    nDay = nDay >> 11;

                    printf("Modification Date    : %d/%d/%d\n", nDay, nMonth, (nYear + 1980));

                    nYear = (stRoot.accessedDate >> 9);
                    nMonth = (stRoot.accessedDate << 7);
                    nMonth = nMonth >> 12;
                    nDay = (stRoot.accessedDate << 11);
                    nDay = nDay >> 11;

                    //printf("Accessed Date        : %d/%d/%d\n", nDay, nMonth, (nYear + 1980));

                    printf("Start Cluster Address: %d\n",
                        stRoot.firstClusterAddress_FAT12);
                    printf("File Size            : %d bytes\n",
                        stRoot.sizeofFile);
                    pByteRoot += 32;
                }    // End of else
            }

            if (bNoEntry)
                break;
            else
            {
                iSector += 1;
            }
        }
    } while (iSector <= 33);

}

void ScanBootSector()
{

    DWORD dwBytesRead;
    char str[128];
    unsigned short num1, num2;
    bool check;

    check = ReadFile(hDisk, (void *)&boot, sizeof(bootRecord), &dwBytesRead, NULL);
    if (!check) {
        printf("Error %d", GetLastError());
    }
    strncpy_s(str, (char *)boot.vendorName, 8);
    str[8] = '\0';
    printf("Vendor Name: %s\n", str);

    if (boot.drivePhysicalNumber >= 0x80)
        puts("Hard disk");
    else
        puts("Floppy disk");
    if (boot.symbolBrackets == '(')
        puts("Extended block present.");
    else
        puts("Extended block absent.");
    memcpy(&num1, boot.volumeSerialNumber, 2);
    memcpy(&num2, boot.volumeSerialNumber + 2, 2);
    printf("Serial num=%X-%X\n", num1, num2);

    strncpy_s(str, (char *)boot.volumeLabel, 11);
    str[11] = '\0';
    printf("Label: %s\n", str);

    strncpy_s(str, (char *)boot.identifierFAT, 8);
    str[8] = '\0';
    printf("Ident FAT: %s\n", str);

    //printf("%d", sizeof(struct param_bios));
    /*printf("Byte in sector = %d\n", boot.extendedBlock.sectorSize);
    printf("Sector in cluster = %d\n", boot.extendedBlock.clusterSize);
    printf("Reserved sector = %d\n", boot.extendedBlock.reservedSectors);
    printf("FAT Count = %d\n", boot.extendedBlock.fatCount);
    printf("root size = %d\n", boot.extendedBlock.rootSize);
    printf("Total sector = %d\n", boot.extendedBlock.totalSectors);
    printf("Media = %d\n", boot.extendedBlock.media);
    printf("Fat size = %d\n", boot.extendedBlock.fatSize);
    printf("Sectors = %d\n", boot.extendedBlock.sectors);
    printf("Heads = %d\n", boot.extendedBlock.heads);
    printf("hidden Low = %d\n", boot.extendedBlock.hiddenLow);
    printf("hidden High  = %d\n", boot.extendedBlock.hiddenHigh);
    printf("largeTotal Sectors = %d\n", boot.extendedBlock.largeTotalSectors[4]);*/

}