Блокирование и доступ к флешке

type
  TDiskGeometry = packed record
    Cylinders: Int64;           // количество цилидров
    MediaType: DWORD;           // тип носителя
    TracksPerCylinder: DWORD;   // дорожек на цилиндре
    SectorsPerTrack: DWORD;     // секторов на дорожке
    BytesPerSector: DWORD;      // байт в секторе
  end;
  TPartitionTableEntry = packed record
    BootIndicator: Byte;          // $80, если активный (загрузочный) раздел
    StartingHead: Byte;
    StartingCylAndSect: Word;
    SystemIndicator: Byte;
    EndingHead: Byte;
    EndingCylAndSect: Word;
    StartingSector: DWORD;        // начальный сектор
    NumberOfSects: DWORD;         // количество секторов
  end;
  TPartitionTable = packed array [0..3] of TPartitionTableEntry;
  PDriveInfo = ^TDriveInfo;
  TDriveInfo = record
    PartitionTable: TPartitionTable;
    LogicalDrives: array [0..3] of PDriveInfo;
  end;
  TPhysicalDrives = array of TDriveInfo;
 
const
  PartitionTableOffset = $1be;
  ExtendedPartitions = [5,$f];
 
  IOCTL_DISK_GET_DRIVE_GEOMETRY = $70000;
 
function ReadSectorsNT(DriveNumber: Byte; StartingSector, SectorCount: DWORD;
  Buffer: Pointer): DWORD;
var
  hFile: THandle;
  br,TmpLo,TmpHi: DWORD;
begin
  Result := 0;
  hFile := CreateFile(PChar('\\.\PhysicalDrive'+IntToStr(DriveNumber)),
    GENERIC_READ,FILE_SHARE_READ,nil,OPEN_EXISTING,FILE_ATTRIBUTE_NORMAL,0);
  if hFile = INVALID_HANDLE_VALUE then Exit;
  TmpLo := __Mul(StartingSector,
    PhysicalDrives[DriveNumber].DiskGeometry.BytesPerSector,TmpHi);
  if SetFilePointer(hFile,TmpLo,@TmpHi,FILE_BEGIN) = TmpLo then
  begin
    SectorCount := SectorCount*PhysicalDrives[DriveNumber].DiskGeometry.BytesPerSector;
    if not ReadFile(hFile,Buffer^,SectorCount,br,nil) then Exit;
    Result := br;
  end;
  CloseHandle(hFile);
 
end;
 
 
procedure InitializeIO;
begin
 if WIN32PLATFORM <> VER_PLATFORM_WIN32_NT then
  begin
    CurDir := GetCurrentDir;
    SetLength(MyName,MAX_PATH);
    GetModuleFileName(hInstance,PChar(MyName),MAX_PATH);
    SetCurrentDir(ExtractFileDir(MyName));
    RawIoLib := LoadLibrary('RAWIO32.BIN');
    SetCurrentDir(CurDir);
    Finalize(MyName);
    EI13GetDriveParameters := GetProcAddress(RawIoLib,'EI13GetDriveParameters');
    EI13ReadSector := GetProcAddress(RawIoLib,'EI13ReadSector');
    EI13WriteSector := GetProcAddress(RawIoLib,'EI13WriteSector');
    ReadSectors := ReadSectors9x;
    WriteSectors := WriteSectors9x;
  end else
  begin
    ReadSectors := ReadSectorsNT;
    WriteSectors := WriteSectorsNT;
  end;
  GetDrivesInfo(PhysicalDrives);
end;
 
 
function __Mul(a,b: DWORD; var HiDWORD: DWORD): DWORD; // Result = LoDWORD
asm
  mul edx
  mov [ecx],edx
end;
 
 
function WriteSectors(DriveNumber: Byte; StartingSector, SectorCount: DWORD;
  Buffer: Pointer; BytesPerSector: DWORD = 512): DWORD;
var
  hFile: THandle;
  bw,TmpLo,TmpHi: DWORD;
begin
  Result := 0;
  hFile := CreateFile(PChar('\\.\PhysicalDrive'+IntToStr(DriveNumber)),
    GENERIC_WRITE,FILE_SHARE_READ,nil,OPEN_EXISTING,FILE_ATTRIBUTE_NORMAL,0);
  if hFile = INVALID_HANDLE_VALUE then Exit;
  TmpLo := __Mul(StartingSector,BytesPerSector,TmpHi);
  if SetFilePointer(hFile,TmpLo,@TmpHi,FILE_BEGIN) = TmpLo then
  begin
    SectorCount := SectorCount*BytesPerSector;
    if not WriteFile(hFile,Buffer^,SectorCount,bw,nil) then Exit;
    Result := bw;
  end;
  CloseHandle(hFile);
end;