Initial commit - WPinternals 2.6

DiscUtils/BuilderSparseStreamExtent.cs

@@ -0,0 +1,74 @@
+//
+// Copyright (c) 2008-2011, Kenneth Bell
+//
+// Permission is hereby granted, free of charge, to any person obtaining a
+// copy of this software and associated documentation files (the "Software"),
+// to deal in the Software without restriction, including without limitation
+// the rights to use, copy, modify, merge, publish, distribute, sublicense,
+// and/or sell copies of the Software, and to permit persons to whom the
+// Software is furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+// DEALINGS IN THE SOFTWARE.
+//
+
+namespace DiscUtils
+{
+    using System;
+    using System.Collections.Generic;
+    using System.Text;
+
+    internal class BuilderSparseStreamExtent : BuilderExtent
+    {
+        private SparseStream _stream;
+        private Ownership _ownership;
+
+        public BuilderSparseStreamExtent(long start, SparseStream stream)
+            : this(start, stream, Ownership.None)
+        {
+        }
+
+        public BuilderSparseStreamExtent(long start, SparseStream stream, Ownership ownership)
+            : base(start, stream.Length)
+        {
+            _stream = stream;
+            _ownership = ownership;
+        }
+
+        public override IEnumerable<StreamExtent> StreamExtents
+        {
+            get { return StreamExtent.Offset(_stream.Extents, Start); }
+        }
+
+        public override void Dispose()
+        {
+            if (_stream != null && _ownership == Ownership.Dispose)
+            {
+                _stream.Dispose();
+                _stream = null;
+            }
+        }
+
+        internal override void PrepareForRead()
+        {
+        }
+
+        internal override int Read(long diskOffset, byte[] block, int offset, int count)
+        {
+            _stream.Position = diskOffset - Start;
+            return _stream.Read(block, offset, count);
+        }
+
+        internal override void DisposeReadState()
+        {
+        }
+    }
+}