public static int GetBytesPerSector(SafeFileHandle hDevice)
{
long size;
DISK_GEOMETRY diskGeometry = GetDiskGeometryAndSize(hDevice, out size);
return((int)diskGeometry.BytesPerSector);
}
public static DISK_GEOMETRY GetDiskGeometryAndSize(SafeFileHandle hDevice, out long diskSize)
{
if (Environment.OSVersion.Version >= new Version(5, 1, 0, 0))
{
// XP and upward
DISK_GEOMETRY_EX diskGeometryEx = GetDiskGeometryEx(hDevice);
diskSize = diskGeometryEx.DiskSize;
return(diskGeometryEx.Geometry);
}
else
{
// Windows 2000
DISK_GEOMETRY diskGeometry = GetDiskGeometry(hDevice);
diskSize = GetPartitionSize(hDevice);
return(diskGeometry);
}
}
/// <summary>
/// Supported on Windows 2000
/// </summary>
public static DISK_GEOMETRY GetDiskGeometry(SafeFileHandle hDevice)
{
uint dummy;
DISK_GEOMETRY diskGeometry = new DISK_GEOMETRY();
IntPtr lpOutBuffer = Marshal.AllocHGlobal(Marshal.SizeOf(diskGeometry));
Marshal.StructureToPtr(diskGeometry, lpOutBuffer, false);
bool success = DeviceIoControl(hDevice, IOCTL_DISK_GET_DRIVE_GEOMETRY, IntPtr.Zero, 0,
lpOutBuffer, (uint)Marshal.SizeOf(typeof(DISK_GEOMETRY)), out dummy, IntPtr.Zero);
diskGeometry = (DISK_GEOMETRY)Marshal.PtrToStructure(lpOutBuffer, typeof(DISK_GEOMETRY));
Marshal.FreeHGlobal(lpOutBuffer);
if (!success)
{
throw new IOException("Unable to retrieve disk geometry");
}
return(diskGeometry);
}
private void PopulateDiskInfo()
{
bool releaseHandle;
SafeFileHandle handle = PhysicalDiskHandlePool.ObtainHandle(m_physicalDiskIndex, FileAccess.Read, ShareMode.ReadWrite, out releaseHandle);
if (!handle.IsInvalid)
{
if (!PhysicalDiskControl.IsMediaAccesible(handle))
{
throw new DeviceNotReadyException();
}
DISK_GEOMETRY diskGeometry = PhysicalDiskControl.GetDiskGeometryAndSize(handle, out m_size);
if (releaseHandle)
{
PhysicalDiskHandlePool.ReleaseHandle(m_physicalDiskIndex);
}
m_bytesPerSector = (int)diskGeometry.BytesPerSector;
// CHS:
m_cylinders = diskGeometry.Cylinders;
m_tracksPerCylinder = (int)diskGeometry.TracksPerCylinder;
m_sectorsPerTrack = (int)diskGeometry.SectorsPerTrack;
}
else
{
// we always release invalid handle
PhysicalDiskHandlePool.ReleaseHandle(m_physicalDiskIndex);
// get error code and throw
int errorCode = Marshal.GetLastWin32Error();
string message = String.Format("Failed to access disk {0}.", m_physicalDiskIndex);
if (errorCode == (int)Win32Error.ERROR_FILE_NOT_FOUND)
{
throw new DriveNotFoundException(message);
}
else
{
IOExceptionHelper.ThrowIOError(errorCode, message);
}
}
}