Exemplo n.º 1
0
        /// <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
            }
        }