blob: 3465cc67b40fc4333e31c79408240d9d3c24d0cd [file] [log] [blame]
James Newton-King79f5bad2020-06-24 16:02:13 +12001#region Copyright notice and license
2// Protocol Buffers - Google's data interchange format
3// Copyright 2008 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
33using System;
34using System.IO;
35using System.Threading;
36using System.Threading.Tasks;
37
38namespace Google.Protobuf
39{
40 /// <summary>
41 /// SecuritySafeCritical attribute can not be placed on types with async methods.
42 /// This class has ByteString's async methods so it can be marked with SecuritySafeCritical.
43 /// </summary>
44 internal static class ByteStringAsync
45 {
46#if !NET35
47 internal static async Task<ByteString> FromStreamAsyncCore(Stream stream, CancellationToken cancellationToken)
48 {
49 int capacity = stream.CanSeek ? checked((int)(stream.Length - stream.Position)) : 0;
50 var memoryStream = new MemoryStream(capacity);
51 // We have to specify the buffer size here, as there's no overload accepting the cancellation token
52 // alone. But it's documented to use 81920 by default if not specified.
53 await stream.CopyToAsync(memoryStream, 81920, cancellationToken);
James Newton-Kinge7949192020-11-18 22:54:06 +130054#if NETSTANDARD1_1
James Newton-King79f5bad2020-06-24 16:02:13 +120055 byte[] bytes = memoryStream.ToArray();
56#else
57 // Avoid an extra copy if we can.
58 byte[] bytes = memoryStream.Length == memoryStream.Capacity ? memoryStream.GetBuffer() : memoryStream.ToArray();
59#endif
60 return ByteString.AttachBytes(bytes);
61 }
62#endif
63 }
64}