1 #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 33 namespace Google.Protobuf 34 { 35 /// <summary> 36 /// This class is used internally by the Protocol Buffer Library and generated 37 /// message implementations. It is public only for the sake of those generated 38 /// messages. Others should not use this class directly. 39 /// <para> 40 /// This class contains constants and helper functions useful for dealing with 41 /// the Protocol Buffer wire format. 42 /// </para> 43 /// </summary> 44 public static class WireFormat 45 { 46 /// <summary> 47 /// Wire types within protobuf encoding. 48 /// </summary> 49 public enum WireType : uint 50 { 51 /// <summary> 52 /// Variable-length integer. 53 /// </summary> 54 Varint = 0, 55 /// <summary> 56 /// A fixed-length 64-bit value. 57 /// </summary> 58 Fixed64 = 1, 59 /// <summary> 60 /// A length-delimited value, i.e. a length followed by that many bytes of data. 61 /// </summary> 62 LengthDelimited = 2, 63 /// <summary> 64 /// A "start group" value 65 /// </summary> 66 StartGroup = 3, 67 /// <summary> 68 /// An "end group" value 69 /// </summary> 70 EndGroup = 4, 71 /// <summary> 72 /// A fixed-length 32-bit value. 73 /// </summary> 74 Fixed32 = 5 75 } 76 77 private const int TagTypeBits = 3; 78 private const uint TagTypeMask = (1 << TagTypeBits) - 1; 79 80 /// <summary> 81 /// Given a tag value, determines the wire type (lower 3 bits). 82 /// </summary> GetTagWireType(uint tag)83 public static WireType GetTagWireType(uint tag) 84 { 85 return (WireType) (tag & TagTypeMask); 86 } 87 88 /// <summary> 89 /// Given a tag value, determines the field number (the upper 29 bits). 90 /// </summary> GetTagFieldNumber(uint tag)91 public static int GetTagFieldNumber(uint tag) 92 { 93 return (int) tag >> TagTypeBits; 94 } 95 96 /// <summary> 97 /// Makes a tag value given a field number and wire type. 98 /// </summary> MakeTag(int fieldNumber, WireType wireType)99 public static uint MakeTag(int fieldNumber, WireType wireType) 100 { 101 return (uint) (fieldNumber << TagTypeBits) | (uint) wireType; 102 } 103 } 104 }