Added the XmlFormatWriter/Reader
diff --git a/src/ProtocolBuffers/Serialization/XmlFormatReader.cs b/src/ProtocolBuffers/Serialization/XmlFormatReader.cs
new file mode 100644
index 0000000..671490e
--- /dev/null
+++ b/src/ProtocolBuffers/Serialization/XmlFormatReader.cs
@@ -0,0 +1,222 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Xml;
+using Google.ProtocolBuffers.Descriptors;
+
+namespace Google.ProtocolBuffers.Serialization
+{
+ /// <summary>
+ /// Parses a proto buffer from an XML document or fragment. .NET 3.5 users may also
+ /// use this class to process Json by setting the options to support Json and providing
+ /// an XmlReader obtained from <see cref="System.Runtime.Serialization.Json.JsonReaderWriterFactory"/>.
+ /// </summary>
+ public class XmlFormatReader : AbstractTextReader
+ {
+ public const string DefaultRootElementName = XmlFormatWriter.DefaultRootElementName;
+ private readonly XmlReader _input;
+ private string _rootElementName;
+
+ static XmlReaderSettings DefaultSettings
+ {
+ get { return new XmlReaderSettings() { CheckCharacters=false, IgnoreComments=true, IgnoreProcessingInstructions = true }; }
+ }
+
+ /// <summary>
+ /// Constructs the XmlFormatReader using the stream provided as the xml
+ /// </summary>
+ public XmlFormatReader(Stream input) : this(XmlReader.Create(input, DefaultSettings)) { }
+ /// <summary>
+ /// Constructs the XmlFormatReader using the string provided as the xml to be read
+ /// </summary>
+ public XmlFormatReader(String input) : this(XmlReader.Create(new StringReader(input))) { }
+ /// <summary>
+ /// Constructs the XmlFormatReader using the xml in the TextReader
+ /// </summary>
+ public XmlFormatReader(TextReader input) : this(XmlReader.Create(input)) { }
+ /// <summary>
+ /// Constructs the XmlFormatReader with the XmlReader
+ /// </summary>
+ public XmlFormatReader(XmlReader input) : this(input, XmlReaderOptions.None) { }
+ /// <summary>
+ /// Constructs the XmlFormatReader with the XmlReader and options
+ /// </summary>
+ public XmlFormatReader(XmlReader input, XmlReaderOptions options)
+ {
+ _input = input;
+ _rootElementName = DefaultRootElementName;
+ Options = options;
+ }
+
+ /// <summary>
+ /// Gets or sets the options to use when reading the xml
+ /// </summary>
+ public XmlReaderOptions Options { get; set; }
+
+ /// <summary>
+ /// Gets or sets the default element name to use when using the Merge<TBuilder>()
+ /// </summary>
+ public string RootElementName
+ {
+ get { return _rootElementName; }
+ set { ThrowHelper.ThrowIfNull(value, "RootElementName"); _rootElementName = value; }
+ }
+
+ private XmlFormatReader CloneWith(XmlReader rdr)
+ {
+ return new XmlFormatReader(rdr, Options);
+ }
+ private void NextElement()
+ {
+ while (!_input.IsStartElement() && _input.Read())
+ continue;
+ }
+ private static void Assert(bool cond)
+ {
+ if (!cond) throw new FormatException();
+ }
+
+ /// <summary>
+ /// Merge the provided builder as an element named <see cref="RootElementName"/> in the current context
+ /// </summary>
+ public override TBuilder Merge<TBuilder>(TBuilder builder, ExtensionRegistry registry)
+ { return Merge(_rootElementName, builder, registry); }
+
+ /// <summary>
+ /// Merge the provided builder as an element of the current context
+ /// </summary>
+ public TBuilder Merge<TBuilder>(string element, TBuilder builder) where TBuilder : IBuilderLite
+ { return Merge(element, builder, ExtensionRegistry.Empty); }
+
+ /// <summary>
+ /// Merge the provided builder as an element of the current context
+ /// </summary>
+ public TBuilder Merge<TBuilder>(string element, TBuilder builder, ExtensionRegistry registry) where TBuilder : IBuilderLite
+ {
+ string field;
+ Assert(PeekNext(out field) && field == element);
+ ReadMessage(builder, registry);
+ return builder;
+ }
+
+ /// <summary>
+ /// Peeks at the next field in the input stream and returns what information is available.
+ /// </summary>
+ /// <remarks>
+ /// This may be called multiple times without actually reading the field. Only after the field
+ /// is either read, or skipped, should PeekNext return a different value.
+ /// </remarks>
+ protected override bool PeekNext(out string field)
+ {
+ NextElement();
+ if(_input.IsStartElement())
+ {
+ field = _input.LocalName;
+ return true;
+ }
+ field = null;
+ return false;
+ }
+
+ /// <summary>
+ /// Causes the reader to skip past this field
+ /// </summary>
+ protected override void Skip()
+ {
+ if (_input.IsStartElement())
+ {
+ if (!_input.IsEmptyElement)
+ {
+ int depth = _input.Depth;
+ while (_input.Depth >= depth && _input.NodeType != XmlNodeType.EndElement)
+ Assert(_input.Read());
+ }
+ _input.Read();
+ }
+ }
+
+ /// <summary>
+ /// returns true if it was able to read a single value into the value reference. The value
+ /// stored may be of type System.String, System.Int32, or an IEnumLite from the IEnumLiteMap.
+ /// </summary>
+ protected override bool ReadEnum(ref object value)
+ {
+ int number;
+ string temp;
+ if (null != (temp = _input.GetAttribute("value")) && int.TryParse(temp, out number))
+ {
+ Skip();
+ value = number;
+ return true;
+ }
+ return base.ReadEnum(ref value);
+ }
+
+ /// <summary>
+ /// Returns true if it was able to read a String from the input
+ /// </summary>
+ protected override bool ReadAsText(ref string value, Type type)
+ {
+ Assert(_input.NodeType == XmlNodeType.Element);
+ value = _input.ReadElementContentAsString();
+
+ return true;
+ }
+
+ /// <summary>
+ /// Merges the input stream into the provided IBuilderLite
+ /// </summary>
+ protected override bool ReadMessage(IBuilderLite builder, ExtensionRegistry registry)
+ {
+ Assert(_input.IsStartElement());
+
+ if (!_input.IsEmptyElement)
+ {
+ int depth = _input.Depth;
+ XmlReader child = _input.ReadSubtree();
+ while (!child.IsStartElement() && child.Read())
+ continue;
+ child.Read();
+ builder.WeakMergeFrom(CloneWith(child), registry);
+ Assert(depth == _input.Depth && _input.NodeType == XmlNodeType.EndElement);
+ }
+ _input.Read();
+ return true;
+ }
+
+ private IEnumerable<string> NonNestedArrayItems(string field)
+ {
+ return base.ForeachArrayItem(field);
+ }
+
+ /// <summary>
+ /// Cursors through the array elements and stops at the end of the array
+ /// </summary>
+ protected override IEnumerable<string> ForeachArrayItem(string field)
+ {
+ bool isNested = (Options & XmlReaderOptions.ReadNestedArrays) != 0;
+
+ if (!isNested)
+ {
+ foreach (string item in NonNestedArrayItems(field))
+ yield return item;
+ yield break;
+ }
+ if (!_input.IsEmptyElement)
+ {
+ int depth = _input.Depth;
+ XmlReader child = _input.ReadSubtree();
+
+ while (!child.IsStartElement() && child.Read())
+ continue;
+ child.Read();
+
+ foreach (string item in CloneWith(child).NonNestedArrayItems("item"))
+ yield return item;
+ Assert(depth == _input.Depth && _input.NodeType == XmlNodeType.EndElement);
+ }
+ _input.Read();
+ yield break;
+ }
+ }
+}