1#region Copyright notice and license
2// Protocol Buffers - Google's data interchange format
3// Copyright 2015 Google Inc.  All rights reserved.
4// https://developers.google.com/protocol-buffers/
5//
6// Redistribution and use in source and binary forms, with or without
7// modification, are permitted provided that the following conditions are
8// met:
9//
10//     * Redistributions of source code must retain the above copyright
11// notice, this list of conditions and the following disclaimer.
12//     * Redistributions in binary form must reproduce the above
13// copyright notice, this list of conditions and the following disclaimer
14// in the documentation and/or other materials provided with the
15// distribution.
16//     * Neither the name of Google Inc. nor the names of its
17// contributors may be used to endorse or promote products derived from
18// this software without specific prior written permission.
19//
20// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
21// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
23// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
24// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
25// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
26// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
27// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
28// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
29// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
30// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31#endregion
32
33#if NET35
34using System;
35using System.IO;
36
37namespace Google.Protobuf.Compatibility
38{
39    /// <summary>
40    /// Extension methods for <see cref="Stream"/> in order to provide
41    /// backwards compatibility with .NET 3.5
42    /// </summary>
43    public static class StreamExtensions
44    {
45        // 81920 seems to be the default buffer size used in .NET 4.5.1
46        private const int BUFFER_SIZE = 81920;
47
48        /// <summary>
49        /// Write the contents of the current stream to the destination stream
50        /// </summary>
51        public static void CopyTo(this Stream source, Stream destination)
52        {
53            if (destination == null)
54            {
55                throw new ArgumentNullException(nameof(destination));
56            }
57
58            byte[] buffer = new byte[BUFFER_SIZE];
59            int numBytesRead;
60            while ((numBytesRead = source.Read(buffer, 0, buffer.Length)) > 0) {
61                destination.Write(buffer, 0, numBytesRead);
62            }
63        }
64    }
65}
66#endif
67