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
#region Copyright notice and license
// Protocol Buffers - Google's data interchange format
// Copyright 2008 Google Inc. All rights reserved.
//
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file or at
// https://developers.google.com/open-source/licenses/bsd
#endregion
namespace Google.Protobuf
{
/// <summary>
/// This class is used internally by the Protocol Buffer Library and generated
/// message implementations. It is public only for the sake of those generated
/// messages. Others should not use this class directly.
/// <para>
/// This class contains constants and helper functions useful for dealing with
/// the Protocol Buffer wire format.
/// </para>
/// </summary>
public static class WireFormat
{
/// <summary>
/// Wire types within protobuf encoding.
/// </summary>
public enum WireType : uint
{
/// <summary>
/// Variable-length integer.
/// </summary>
Varint = 0,
/// <summary>
/// A fixed-length 64-bit value.
/// </summary>
Fixed64 = 1,
/// <summary>
/// A length-delimited value, i.e. a length followed by that many bytes of data.
/// </summary>
LengthDelimited = 2,
/// <summary>
/// A "start group" value
/// </summary>
StartGroup = 3,
/// <summary>
/// An "end group" value
/// </summary>
EndGroup = 4,
/// <summary>
/// A fixed-length 32-bit value.
/// </summary>
Fixed32 = 5
}
private const int TagTypeBits = 3;
private const uint TagTypeMask = (1 << TagTypeBits) - 1;
/// <summary>
/// Given a tag value, determines the wire type (lower 3 bits).
/// </summary>
public static WireType GetTagWireType(uint tag)
{
return (WireType) (tag & TagTypeMask);
}
/// <summary>
/// Given a tag value, determines the field number (the upper 29 bits).
/// </summary>
public static int GetTagFieldNumber(uint tag)
{
return (int) (tag >> TagTypeBits);
}
/// <summary>
/// Makes a tag value given a field number and wire type.
/// </summary>
public static uint MakeTag(int fieldNumber, WireType wireType)
{
return (uint) (fieldNumber << TagTypeBits) | (uint) wireType;
}
}
}