/// <summary>
/// Sector refers to physical disk blocks, we can only read complete blocks
/// </summary>
public byte[] ReadSectorsUnbuffered(long sectorIndex, int sectorCount)
{
bool releaseHandle;
SafeFileHandle handle = VolumeHandlePool.ObtainHandle(m_volumeGuid, FileAccess.Read, ShareMode.ReadWrite, out releaseHandle);
if (!handle.IsInvalid)
{
FileStreamEx stream = new FileStreamEx(handle, FileAccess.Read);
byte[] buffer = new byte[m_bytesPerSector * sectorCount];
try
{
stream.Seek(sectorIndex * m_bytesPerSector, SeekOrigin.Begin);
stream.Read(buffer, 0, m_bytesPerSector * sectorCount);
}
finally
{
stream.Close(releaseHandle);
if (releaseHandle)
{
VolumeHandlePool.ReleaseHandle(m_volumeGuid);
}
}
return(buffer);
}
else
{
// we always release invalid handle
VolumeHandlePool.ReleaseHandle(m_volumeGuid);
// get error code and throw
int errorCode = Marshal.GetLastWin32Error();
string message = String.Format("Can't read sector {0} from volume {1}, Win32 Error: {2}", sectorIndex, m_volumeGuid, errorCode);
throw new IOException(message);
}
}
/// <summary>
/// Sector refers to physical disk blocks, we can only read complete blocks
/// </summary>
public byte[] ReadSectorsUnbuffered(long sectorIndex, int sectorCount)
{
bool releaseHandle;
SafeFileHandle handle = PhysicalDiskHandlePool.ObtainHandle(m_physicalDiskIndex, FileAccess.Read, ShareMode.ReadWrite, out releaseHandle);
if (!handle.IsInvalid)
{
FileStreamEx stream = new FileStreamEx(handle, FileAccess.Read);
byte[] buffer = new byte[m_bytesPerSector * sectorCount];
try
{
stream.Seek(sectorIndex * m_bytesPerSector, SeekOrigin.Begin);
stream.Read(buffer, 0, m_bytesPerSector * sectorCount);
}
finally
{
stream.Close(releaseHandle);
if (releaseHandle)
{
PhysicalDiskHandlePool.ReleaseHandle(m_physicalDiskIndex);
}
}
return(buffer);
}
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 read sector {0} from disk {1}.", sectorIndex, m_physicalDiskIndex);
IOExceptionHelper.ThrowIOError(errorCode, message);
return(null); // this line will not be reached
}
}
public void WriteSectorsUnbuffered(long sectorIndex, byte[] data)
{
if (data.Length % m_bytesPerSector > 0)
{
throw new IOException("Cannot write partial sectors");
}
if (IsReadOnly)
{
throw new UnauthorizedAccessException("Attempted to perform write on a readonly disk");
}
bool releaseHandle;
SafeFileHandle handle = PhysicalDiskHandlePool.ObtainHandle(m_physicalDiskIndex, FileAccess.ReadWrite, ShareMode.Read, out releaseHandle);
if (!handle.IsInvalid)
{
FileStreamEx stream = new FileStreamEx(handle, FileAccess.Write);
try
{
stream.Seek(sectorIndex * m_bytesPerSector, SeekOrigin.Begin);
stream.Write(data, 0, data.Length);
stream.Flush();
}
finally
{
stream.Close(releaseHandle);
if (releaseHandle)
{
PhysicalDiskHandlePool.ReleaseHandle(m_physicalDiskIndex);
}
}
}
else
{
// we always release invalid handle
PhysicalDiskHandlePool.ReleaseHandle(m_physicalDiskIndex);
// get error code and throw
int errorCode = Marshal.GetLastWin32Error();
string message = String.Format("Can't write to sector {0} of disk {1}", sectorIndex, m_physicalDiskIndex);
FileStreamEx.ThrowIOError(errorCode, message);
}
}
public void WriteSectorsUnbuffered(long sectorIndex, byte[] data)
{
if (data.Length % m_bytesPerSector > 0)
{
throw new IOException("Cannot write partial sectors");
}
if (!m_isReadOnly)
{
bool releaseHandle;
SafeFileHandle handle = VolumeHandlePool.ObtainHandle(m_volumeGuid, FileAccess.ReadWrite, ShareMode.None, out releaseHandle);
if (!handle.IsInvalid)
{
FileStreamEx stream = new FileStreamEx(handle, FileAccess.Write);
try
{
stream.Seek(sectorIndex * m_bytesPerSector, SeekOrigin.Begin);
stream.Write(data, 0, data.Length);
stream.Flush();
}
finally
{
stream.Close(releaseHandle);
if (releaseHandle)
{
VolumeHandlePool.ReleaseHandle(m_volumeGuid);
}
}
}
else
{
// we always release invalid handle
VolumeHandlePool.ReleaseHandle(m_volumeGuid);
// get error code and throw
int errorCode = Marshal.GetLastWin32Error();
string message = String.Format("Can't write to sector {0} of volume {1}, Win32 errorCode: {2}", sectorIndex, m_volumeGuid, errorCode);
throw new IOException(message);
}
}
}