1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
|
//
// BufferedReadStream.cs
//
// Author:
// Martin Baulig <mabaul@microsoft.com>
//
// Copyright (c) 2018 Xamarin Inc. (http://www.xamarin.com)
//
// 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.
using System;
using System.IO;
using System.Threading;
using System.Threading.Tasks;
namespace System.Net
{
class BufferedReadStream : WebReadStream
{
readonly BufferOffsetSize readBuffer;
public BufferedReadStream (WebOperation operation, Stream innerStream,
BufferOffsetSize readBuffer)
: base (operation, innerStream)
{
this.readBuffer = readBuffer;
}
protected override async Task<int> ProcessReadAsync (
byte[] buffer, int offset, int size,
CancellationToken cancellationToken)
{
cancellationToken.ThrowIfCancellationRequested ();
var remaining = readBuffer?.Size ?? 0;
if (remaining > 0) {
int copy = (remaining > size) ? size : remaining;
Buffer.BlockCopy (readBuffer.Buffer, readBuffer.Offset, buffer, offset, copy);
readBuffer.Offset += copy;
readBuffer.Size -= copy;
offset += copy;
size -= copy;
return copy;
}
if (InnerStream == null)
return 0;
return await InnerStream.ReadAsync (
buffer, offset, size, cancellationToken).ConfigureAwait (false);
}
internal bool TryReadFromBuffer (byte[] buffer, int offset, int size, out int result)
{
var remaining = readBuffer?.Size ?? 0;
if (remaining <= 0) {
result = 0;
return InnerStream == null;
}
int copy = (remaining > size) ? size : remaining;
Buffer.BlockCopy (readBuffer.Buffer, readBuffer.Offset, buffer, offset, copy);
readBuffer.Offset += copy;
readBuffer.Size -= copy;
offset += copy;
size -= copy;
result = copy;
return true;
}
}
}
|
