1 files changed, 92 insertions, 0 deletions
diff --git a/csharp/src/ProtocolBuffers/ByteArray.cs b/csharp/src/ProtocolBuffers/ByteArray.cs
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+++ b/csharp/src/ProtocolBuffers/ByteArray.cs
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+#region Copyright notice and license
+
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// http://github.com/jskeet/dotnet-protobufs/
+// Original C++/Java/Python code:
+// http://code.google.com/p/protobuf/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#endregion
+
+using System;
+
+namespace Google.ProtocolBuffers
+{
+    /// <summary>
+    /// Provides a utility routine to copy small arrays much more quickly than Buffer.BlockCopy
+    /// </summary>
+    internal static class ByteArray
+    {
+        /// <summary>
+        /// The threshold above which you should use Buffer.BlockCopy rather than ByteArray.Copy
+        /// </summary>
+        private const int CopyThreshold = 12;
+
+        /// <summary>
+        /// Determines which copy routine to use based on the number of bytes to be copied.
+        /// </summary>
+        public static void Copy(byte[] src, int srcOffset, byte[] dst, int dstOffset, int count)
+        {
+            if (count > CopyThreshold)
+            {
+                Buffer.BlockCopy(src, srcOffset, dst, dstOffset, count);
+            }
+            else
+            {
+                ByteCopy(src, srcOffset, dst, dstOffset, count);
+            }
+        }
+
+        /// <summary>
+        /// Copy the bytes provided with a for loop, faster when there are only a few bytes to copy
+        /// </summary>
+        public static void ByteCopy(byte[] src, int srcOffset, byte[] dst, int dstOffset, int count)
+        {
+            int stop = srcOffset + count;
+            for (int i = srcOffset; i < stop; i++)
+            {
+                dst[dstOffset++] = src[i];
+            }
+        }
+
+        /// <summary>
+        /// Reverses the order of bytes in the array
+        /// </summary>
+        public static void Reverse(byte[] bytes)
+        {
+            byte temp;
+            for (int first = 0, last = bytes.Length - 1; first < last; first++, last--)
+            {
+                temp = bytes[first];
+                bytes[first] = bytes[last];
+                bytes[last] = temp;
+            }
+        }
+    }
+}
+\ No newline at end of file