#region Copyright notice and license
// Protocol Buffers - Google's data interchange format
// Copyright 2008 Google Inc. All rights reserved.
// http://github.com/jskeet/dotnet-protobufs/
// Original C++/Java/Python code:
// http://code.google.com/p/protobuf/
//
// 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.Descriptors;
namespace Google.Protobuf
{
///
/// 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.
///
/// This class contains constants and helper functions useful for dealing with
/// the Protocol Buffer wire format.
///
///
public static class WireFormat
{
#region Fixed sizes.
// TODO(jonskeet): Move these somewhere else. They're messy. Consider making FieldType a smarter kind of enum
public const int Fixed32Size = 4;
public const int Fixed64Size = 8;
public const int SFixed32Size = 4;
public const int SFixed64Size = 8;
public const int FloatSize = 4;
public const int DoubleSize = 8;
public const int BoolSize = 1;
#endregion
public enum WireType : uint
{
Varint = 0,
Fixed64 = 1,
LengthDelimited = 2,
StartGroup = 3,
EndGroup = 4,
Fixed32 = 5
}
internal static class MessageSetField
{
internal const int Item = 1;
internal const int TypeID = 2;
internal const int Message = 3;
}
internal static class MessageSetTag
{
internal static readonly uint ItemStart = MakeTag(MessageSetField.Item, WireType.StartGroup);
internal static readonly uint ItemEnd = MakeTag(MessageSetField.Item, WireType.EndGroup);
internal static readonly uint TypeID = MakeTag(MessageSetField.TypeID, WireType.Varint);
internal static readonly uint Message = MakeTag(MessageSetField.Message, WireType.LengthDelimited);
}
private const int TagTypeBits = 3;
private const uint TagTypeMask = (1 << TagTypeBits) - 1;
///
/// Given a tag value, determines the wire type (lower 3 bits).
///
public static WireType GetTagWireType(uint tag)
{
return (WireType) (tag & TagTypeMask);
}
public static bool IsEndGroupTag(uint tag)
{
return (WireType) (tag & TagTypeMask) == WireType.EndGroup;
}
///
/// Given a tag value, determines the field number (the upper 29 bits).
///
public static int GetTagFieldNumber(uint tag)
{
return (int) tag >> TagTypeBits;
}
///
/// Makes a tag value given a field number and wire type.
///
public static uint MakeTag(int fieldNumber, WireType wireType)
{
return (uint) (fieldNumber << TagTypeBits) | (uint) wireType;
}
#if !LITE
public static uint MakeTag(FieldDescriptor field)
{
return MakeTag(field.FieldNumber, GetWireType(field));
}
///
/// Returns the wire type for the given field descriptor. This differs
/// from GetWireType(FieldType) for packed repeated fields.
///
internal static WireType GetWireType(FieldDescriptor descriptor)
{
return descriptor.IsPacked ? WireType.LengthDelimited : GetWireType(descriptor.FieldType);
}
#endif
///
/// 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.
///
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("No such field type");
}
}
}
}