generator: added conversion for byref structs

The pointer from native is stored inside of a class which
wraps the structure. Fields can be accessed by marshalling
from and to the pointer. glib: Value.Update does now invoke
a private Update() method which is needed to update the new
structures.

generator/FieldBase.cs

@@ -40,7 +40,7 @@ namespace GtkSharp.Generation {
 			return true;
 		}
 
-		protected virtual bool Readable {
+		internal virtual bool Readable {
 			get {
 				if (Parser.GetVersion (elem.OwnerDocument.DocumentElement) <= 2)
 					return elem.GetAttribute ("readable") != "false";
@@ -48,7 +48,7 @@ namespace GtkSharp.Generation {
 			}
 		}
 
-		protected virtual bool Writable {
+		internal virtual bool Writable {
 			get {
 				if (Parser.GetVersion (elem.OwnerDocument.DocumentElement) <= 2)
 					return elem.GetAttribute ("writeable") != "false";
@@ -58,7 +58,7 @@ namespace GtkSharp.Generation {
 
 		protected abstract string DefaultAccess { get; }
 
-		protected string Access {
+		internal string Access {
 			get {
 				return elem.HasAttribute ("access") ? elem.GetAttribute ("access") : DefaultAccess;
 			}

generator/Makefile.am

@@ -43,6 +43,7 @@ sources = 				\
 	MethodBase.cs			\
 	MethodBody.cs			\
 	Method.cs			\
+	NativeStructGen.cs		\
 	ObjectField.cs			\
 	ObjectBase.cs			\
 	ObjectGen.cs			\

generator/NativeStructGen.cs

@@ -0,0 +1,232 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Text;
+using System.Text.RegularExpressions;
+using System.Xml;
+
+namespace GtkSharp.Generation
+{
+	public class NativeStructGen : HandleBase
+	{
+		IList<StructField> fields = new List<StructField> ();
+		bool need_read_native = false;
+		string native_struct_name;
+
+		public NativeStructGen (XmlElement ns, XmlElement elem) : base (ns, elem)
+		{
+			native_struct_name = Name + "Impl";
+
+			foreach (XmlNode node in elem.ChildNodes) {
+
+				if (!(node is XmlElement)) continue;
+				XmlElement member = (XmlElement) node;
+
+				switch (node.Name) {
+				case "field":
+					fields.Add (new StructField (member, this));
+					break;
+
+				default:
+					if (!IsNodeNameHandled (node.Name))
+						Console.WriteLine ("Unexpected node " + node.Name + " in " + CName);
+					break;
+				}
+			}
+		}
+
+		public override string MarshalType {
+			get {
+				return "IntPtr";
+			}
+		}
+
+		public override string AssignToName {
+			get { return "Handle"; }
+		}
+
+		public override string CallByName ()
+		{
+			return "Handle";
+		}
+
+		public override string CallByName (string var)
+		{
+			return String.Format ("{0} == null ? IntPtr.Zero : {0}.{1}", var, "Handle");
+		}
+
+		public override string FromNative (string var, bool owned)
+		{
+			return "new " + QualifiedName + "( " + var + " )";
+		}
+
+		public override void Generate (GenerationInfo gen_info)
+		{
+			bool need_close = false;
+			if (gen_info.Writer == null) {
+				gen_info.Writer = gen_info.OpenStream (Name);
+				need_close = true;
+			}
+
+			StreamWriter sw = gen_info.Writer;
+			
+			sw.WriteLine ("namespace " + NS + " {");
+			sw.WriteLine ();
+			sw.WriteLine ("\tusing System;");
+			sw.WriteLine ("\tusing System.Collections;");
+			sw.WriteLine ("\tusing System.Collections.Generic;");
+			sw.WriteLine ("\tusing System.Runtime.InteropServices;");
+			sw.WriteLine ();
+
+			sw.WriteLine ("#region Autogenerated code");
+			if (IsDeprecated)
+				sw.WriteLine ("\t[Obsolete]");
+			string access = IsInternal ? "internal" : "public";
+			sw.WriteLine ("\t" + access + " partial class {0} : IEquatable<{0}> {{", Name);
+			sw.WriteLine ();
+
+			need_read_native = false;
+			GenNativeStruct (gen_info);
+			GenUpdate (gen_info);
+			GenFields (gen_info);
+			sw.WriteLine ();
+			GenCtors (gen_info);
+			GenMethods (gen_info, null, this);
+			if (need_read_native)
+				GenUpdate (gen_info);
+			GenEqualsAndHash (sw);
+
+			if (!need_close)
+				return;
+
+			sw.WriteLine ("#endregion");
+
+			sw.WriteLine ("\t}");
+			sw.WriteLine ("}");
+			sw.Close ();
+			gen_info.Writer = null;
+		}
+
+		private void GenNativeStruct (GenerationInfo gen_info)
+		{
+			StreamWriter sw = gen_info.Writer;
+
+			sw.WriteLine ("\t\t[StructLayout(LayoutKind.Sequential)]");
+			sw.WriteLine ("\t\tprivate struct {0} {{", native_struct_name);
+			foreach (StructField field in fields) {
+				field.Generate (gen_info, "\t\t\t");
+			}
+			sw.WriteLine ("\t\t}");
+			sw.WriteLine ();
+		}
+
+		private void GenUpdate (GenerationInfo gen_info)
+		{
+			StreamWriter sw = gen_info.Writer;
+
+			sw.WriteLine ("\t\tprivate void Update ()", QualifiedName);
+			sw.WriteLine ("\t\t{");
+			sw.WriteLine ("\t\t\tthis.managed_struct = ({0})Marshal.PtrToStructure (this.Handle, typeof({0}));", native_struct_name);
+			sw.WriteLine ("\t\t}");
+			sw.WriteLine ();
+		}
+
+		protected override void GenCtors (GenerationInfo gen_info)
+		{
+			StreamWriter sw = gen_info.Writer;
+
+			sw.WriteLine ("\t\tpublic {0} (IntPtr raw)", Name);
+			sw.WriteLine ("\t\t{");
+			sw.WriteLine ("\t\t\tthis.Handle = raw;");
+			sw.WriteLine ("\t\t}");
+			sw.WriteLine ();
+
+			base.GenCtors (gen_info);
+		}
+
+		protected new void GenFields (GenerationInfo gen_info)
+		{
+			StreamWriter sw = gen_info.Writer;
+			sw.WriteLine ("\t\tprivate IntPtr Raw;");
+			sw.WriteLine ("\t\tpublic IntPtr Handle {");
+			sw.WriteLine ("\t\t\tget { return Raw; }");
+			sw.WriteLine ("\t\t\tset { Raw = value; Update ();}");
+			sw.WriteLine ("\t\t}");
+			sw.WriteLine ("\t\tprivate {0} managed_struct;", native_struct_name);
+			sw.WriteLine ();
+			foreach (StructField field in fields) {
+				if (!field.Visible)
+					continue;
+				sw.WriteLine ("\t\tpublic {0} {1} {{", SymbolTable.Table.GetCSType (field.CType), field.StudlyName);
+				sw.WriteLine ("\t\t\tget {{ Update(); return {0}.{1}; }}", "managed_struct", field.StudlyName);
+				if (!(SymbolTable.Table [field.CType] is CallbackGen))
+					sw.WriteLine ("\t\t\tset {{ Update(); {0}.{1} = value;  Marshal.StructureToPtr({0}, this.Handle, false); }}" , "managed_struct", field.StudlyName);
+				sw.WriteLine ("\t\t}");
+			}
+		}
+
+		protected void GenEqualsAndHash (StreamWriter sw)
+		{
+			int bitfields = 0;
+			bool need_field = true;
+			StringBuilder hashcode = new StringBuilder ();
+			StringBuilder equals = new StringBuilder ();
+
+			sw.WriteLine ("\t\tpublic bool Equals ({0} other)", Name);
+			sw.WriteLine ("\t\t{");
+			hashcode.Append ("this.GetType().FullName.GetHashCode()");
+			equals.Append ("true");
+
+			foreach (StructField field in fields) {
+				if (field.IsPadding || !field.Visible)
+					continue;
+				if (field.IsBitfield) {
+					if (need_field) {
+						equals.Append (" && _bitfield");
+						equals.Append (bitfields);
+						equals.Append (".Equals (other._bitfield");
+						equals.Append (bitfields);
+						equals.Append (")");
+						hashcode.Append (" ^ ");
+						hashcode.Append ("_bitfield");
+						hashcode.Append (bitfields++);
+						hashcode.Append (".GetHashCode ()");
+						need_field = false;
+					}
+				} else {
+					need_field = true;
+					equals.Append (" && ");
+					equals.Append (field.EqualityName);
+					equals.Append (".Equals (other.");
+					equals.Append (field.EqualityName);
+					equals.Append (")");
+					hashcode.Append (" ^ ");
+					hashcode.Append (field.EqualityName);
+					hashcode.Append (".GetHashCode ()");
+				}
+			}
+			sw.WriteLine ("\t\t\treturn {0};", equals.ToString ());
+			sw.WriteLine ("\t\t}");
+			sw.WriteLine ();
+			sw.WriteLine ("\t\tpublic override bool Equals (object other)");
+			sw.WriteLine ("\t\t{");
+			sw.WriteLine ("\t\t\treturn other is {0} && Equals (({0}) other);", Name);
+			sw.WriteLine ("\t\t}");
+			sw.WriteLine ();
+			if (Elem.GetAttribute ("nohash") == "true")
+				return;
+			sw.WriteLine ("\t\tpublic override int GetHashCode ()");
+			sw.WriteLine ("\t\t{");
+			sw.WriteLine ("\t\t\treturn {0};", hashcode.ToString ());
+			sw.WriteLine ("\t\t}");
+			sw.WriteLine ();
+
+		}
+
+		public override void Prepare (StreamWriter sw, string indent)
+		{
+			sw.WriteLine (indent + "Update ();");
+		}
+	}
+}
+

generator/ObjectField.cs

@@ -32,7 +32,7 @@ namespace GtkSharp.Generation {
 				ctype = "const-" + CType;
 		}
 
-		protected override bool Writable {
+		internal override bool Writable {
 			get {
 				return elem.GetAttributeAsBoolean ("writeable");
 			}

generator/Parser.cs

@@ -140,6 +140,7 @@ namespace GtkSharp.Generation {
 					continue;
 
 				bool is_opaque = elem.GetAttributeAsBoolean ("opaque");
+				bool is_native_struct = elem.GetAttributeAsBoolean ("native");
 
 				switch (def.Name) {
 				case "alias":
@@ -177,6 +178,8 @@ namespace GtkSharp.Generation {
 				case "struct":
 					if (is_opaque) {
 						result.Add (new OpaqueGen (ns, elem));
+					} else if (is_native_struct) {
+						result.Add (new NativeStructGen (ns, elem));
 					} else {
 						result.Add (new StructGen (ns, elem));
 					}

generator/StructField.cs

@@ -70,6 +70,13 @@ namespace GtkSharp.Generation {
 			}
 		}
 
+		bool visible = false;
+		internal bool Visible {
+			get {
+				return visible;
+			}
+		}
+
 		public string EqualityName {
 			get {
 				SymbolTable table = SymbolTable.Table;
@@ -127,6 +134,8 @@ namespace GtkSharp.Generation {
 			if (Hidden)
 				return;
 
+			visible = Access != "private";
+
 			StreamWriter sw = gen_info.Writer;
 			SymbolTable table = SymbolTable.Table;
 
@@ -158,6 +167,7 @@ namespace GtkSharp.Generation {
 				}
 			} else if (IsPointer && CSType != "string") {
 				// FIXME: probably some fields here which should be visible.
+				visible = false;
 				sw.WriteLine (indent + "private {0} {1};", CSType, Name);
 			} else {
 				sw.WriteLine (indent + "{0} {1} {2};", Access, CSType, Access == "public" ? StudlyName : Name);

generator/generator.csproj

@@ -93,6 +93,7 @@
     <Compile Include="Options.cs" />
     <Compile Include="Constant.cs" />
     <Compile Include="UnionGen.cs" />
+    <Compile Include="NativeStructGen.cs" />
   </ItemGroup>
   <ItemGroup>
     <None Include="DESIGN" />

glib/Value.cs

@@ -421,10 +421,14 @@ namespace GLib {
 				return (GLib.Opaque) this;
 
 			MethodInfo mi = t.GetMethod ("New", BindingFlags.Static | BindingFlags.Public | BindingFlags.FlattenHierarchy);
-			if (mi == null)
-				return Marshal.PtrToStructure (boxed_ptr, t);
-			else
+			if (mi != null)
 				return mi.Invoke (null, new object[] {boxed_ptr});
+
+			ConstructorInfo ci = t.GetConstructor (new Type[] { typeof(IntPtr) });
+			if (ci != null)
+				return ci.Invoke (new object[] { boxed_ptr });
+
+			return Marshal.PtrToStructure (boxed_ptr, t);
 		}
 
 		public object Val
@@ -548,8 +552,15 @@ namespace GLib {
 
 		internal void Update (object val)
 		{
-			if (GType.Is (type, GType.Boxed) && !(val is IWrapper))
-				Marshal.StructureToPtr (val, g_value_get_boxed (ref this), false);
+			Type t = GType.LookupType (type);
+			if (GType.Is (type, GType.Boxed) && !(val is IWrapper)) {
+				MethodInfo mi = val.GetType ().GetMethod ("Update", BindingFlags.NonPublic | BindingFlags.Instance);
+				IntPtr boxed_ptr = g_value_get_boxed (ref this);
+				if (mi == null)
+					Marshal.StructureToPtr (val, boxed_ptr, false);
+				else
+					mi.Invoke (val, null);
+			}
 		}
 
 		bool HoldsFlags {