Refactor image classes and split them to smaller files.

DiscImageChef.DiscImages/Partimage/Helpers.cs

@@ -0,0 +1,44 @@
+// /***************************************************************************
+// The Disc Image Chef
+// ----------------------------------------------------------------------------
+//
+// Filename       : Helpers.cs
+// Author(s)      : Natalia Portillo <claunia@claunia.com>
+//
+// Component      : Disk image plugins.
+//
+// --[ Description ] ----------------------------------------------------------
+//
+//     Contains helpers for partimage disk images.
+//
+// --[ License ] --------------------------------------------------------------
+//
+//     This library is free software; you can redistribute it and/or modify
+//     it under the terms of the GNU Lesser General Public License as
+//     published by the Free Software Foundation; either version 2.1 of the
+//     License, or (at your option) any later version.
+//
+//     This library is distributed in the hope that it will be useful, but
+//     WITHOUT ANY WARRANTY; without even the implied warranty of
+//     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+//     Lesser General Public License for more details.
+//
+//     You should have received a copy of the GNU Lesser General Public
+//     License along with this library; if not, see <http://www.gnu.org/licenses/>.
+//
+// ----------------------------------------------------------------------------
+// Copyright © 2011-2018 Natalia Portillo
+// ****************************************************************************/
+
+namespace DiscImageChef.DiscImages
+{
+    public partial class Partimage
+    {
+        ulong BlockOffset(ulong sectorAddress)
+        {
+            extents.GetStart(sectorAddress, out ulong extentStart);
+            extentsOff.TryGetValue(extentStart, out ulong extentStartingOffset);
+            return extentStartingOffset + (sectorAddress - extentStart);
+        }
+    }
+}