#region Copyright notice and license | |
// Protocol Buffers - Google's data interchange format | |
// Copyright 2008 Google Inc. All rights reserved. | |
// https://developers.google.com/protocol-buffers/ | |
// | |
// Redistribution and use in source and binary forms, with or without | |
// modification, are permitted provided that the following conditions are | |
// met: | |
// | |
// * Redistributions of source code must retain the above copyright | |
// notice, this list of conditions and the following disclaimer. | |
// * Redistributions in binary form must reproduce the above | |
// copyright notice, this list of conditions and the following disclaimer | |
// in the documentation and/or other materials provided with the | |
// distribution. | |
// * Neither the name of Google Inc. nor the names of its | |
// contributors may be used to endorse or promote products derived from | |
// this software without specific prior written permission. | |
// | |
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS | |
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT | |
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR | |
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT | |
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, | |
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT | |
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, | |
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY | |
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT | |
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE | |
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. | |
#endregion | |
using System; | |
using Google.Protobuf.Reflection; | |
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 | |
{ | |
#region Fixed sizes. | |
// TODO(jonskeet): Move these somewhere else. They're messy. Consider making FieldType a smarter kind of enum | |
internal const int Fixed32Size = 4; | |
internal const int Fixed64Size = 8; | |
internal const int SFixed32Size = 4; | |
internal const int SFixed64Size = 8; | |
internal const int FloatSize = 4; | |
internal const int DoubleSize = 8; | |
internal const int BoolSize = 1; | |
#endregion | |
public enum WireType : uint | |
{ | |
Varint = 0, | |
Fixed64 = 1, | |
LengthDelimited = 2, | |
StartGroup = 3, | |
EndGroup = 4, | |
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); | |
} | |
public static bool IsEndGroupTag(uint tag) | |
{ | |
return (WireType) (tag & TagTypeMask) == WireType.EndGroup; | |
} | |
/// <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; | |
} | |
public static uint MakeTag(FieldDescriptor field) | |
{ | |
return MakeTag(field.FieldNumber, GetWireType(field)); | |
} | |
/// <summary> | |
/// Returns the wire type for the given field descriptor. This differs | |
/// from GetWireType(FieldType) for packed repeated fields. | |
/// </summary> | |
internal static WireType GetWireType(FieldDescriptor descriptor) | |
{ | |
return descriptor.IsPacked ? WireType.LengthDelimited : GetWireType(descriptor.FieldType); | |
} | |
/// <summary> | |
/// Converts a field type to its wire type. Done with a switch for the sake | |
/// of speed - this is significantly faster than a dictionary lookup. | |
/// </summary> | |
public static WireType GetWireType(FieldType fieldType) | |
{ | |
switch (fieldType) | |
{ | |
case FieldType.Double: | |
return WireType.Fixed64; | |
case FieldType.Float: | |
return WireType.Fixed32; | |
case FieldType.Int64: | |
case FieldType.UInt64: | |
case FieldType.Int32: | |
return WireType.Varint; | |
case FieldType.Fixed64: | |
return WireType.Fixed64; | |
case FieldType.Fixed32: | |
return WireType.Fixed32; | |
case FieldType.Bool: | |
return WireType.Varint; | |
case FieldType.String: | |
return WireType.LengthDelimited; | |
case FieldType.Group: | |
return WireType.StartGroup; | |
case FieldType.Message: | |
case FieldType.Bytes: | |
return WireType.LengthDelimited; | |
case FieldType.UInt32: | |
return WireType.Varint; | |
case FieldType.SFixed32: | |
return WireType.Fixed32; | |
case FieldType.SFixed64: | |
return WireType.Fixed64; | |
case FieldType.SInt32: | |
case FieldType.SInt64: | |
case FieldType.Enum: | |
return WireType.Varint; | |
default: | |
throw new ArgumentOutOfRangeException("fieldType", "No such field type"); | |
} | |
} | |
} | |
} |