First cut at new layout

1 files changed, 122 insertions, 0 deletions

diff --git a/src/ProtocolBuffers/WireFormat.cs b/src/ProtocolBuffers/WireFormat.cs
new file mode 100644
index 00000000..0ea93322
--- /dev/null
+++ b/src/ProtocolBuffers/WireFormat.cs
@@ -0,0 +1,122 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.
+// http://code.google.com/p/protobuf/
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+using System;
+using System.Reflection;
+using Google.ProtocolBuffers.Descriptors;
+using System.Collections.Generic;
+using Google.ProtocolBuffers.Collections;
+namespace Google.ProtocolBuffers {
+  
+  /// <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 {
+    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;
+
+    /// <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.
+    /// TODO(jonskeet): Should we just have a Tag structure?
+    /// </summary>
+    public static uint MakeTag(int fieldNumber, WireType wireType) {
+      return (uint) (fieldNumber << TagTypeBits) | (uint) wireType;
+    }
+
+    /// <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("No such field type");
+      }
+    }
+  }
+}