generator: fixed optional array parameters

generator/Signature.cs

@@ -149,7 +149,10 @@ namespace GtkSharp.Generation {
 
 				result [i] = p.PassAs != "" ? p.PassAs + " " : "";
 				if (p.IsOptional && p.PassAs == String.Empty) {
-					result [i++] += p.Generatable.DefaultValue;
+					if (p.IsArray)
+						result [i++] += "null";
+					else
+						result [i++] += p.Generatable.DefaultValue;
 				}
 				else
 					result [i++] += p.Name;

generator/StructField.cs

@@ -58,6 +58,10 @@ namespace GtkSharp.Generation {
 			}
 		}
 
+		bool IsNullTermArray {
+			get { return elem.GetAttributeAsBoolean ("null_term_array"); }
+		}
+
 		public new string CSType {
 			get {
 				string type = base.CSType;
@@ -143,9 +147,21 @@ namespace GtkSharp.Generation {
 			string wrapped_name = SymbolTable.Table.MangleName (CName);
 			IGeneratable gen = table [CType];
 
-			if (IsArray) {
+			if (IsArray && !IsNullTermArray) {
 				sw.WriteLine (indent + "[MarshalAs (UnmanagedType.ByValArray, SizeConst=" + ArrayLength + ")]");
 				sw.WriteLine (indent + "{0} {1} {2};", Access, CSType, StudlyName);
+			} else if (IsArray && IsNullTermArray) {
+				sw.WriteLine (indent + "private {0} {1};", "IntPtr", StudlyName+ "Ptr");
+				if ((Readable || Writable) && Access == "public") {
+					sw.WriteLine (indent + "public {0} {1} {{", CSType, StudlyName);
+					if (Readable)
+						sw.WriteLine (indent + "\tget {{ return GLib.Marshaller.StructArrayFromNullTerminatedIntPtr<{0}> ({1}); }}",
+						              base.CSType, StudlyName + "Ptr");
+					if (Writable)
+						sw.WriteLine (indent + "\tset {{ {0} = GLib.Marshaller.StructArrayToNullTerminatedStructArrayIntPtr<{1}> (value); }}",
+						              StudlyName + "Ptr", base.CSType);
+					sw.WriteLine (indent + "}");
+				}
 			} else if (IsBitfield) {
 				base.Generate (gen_info, indent);
 			} else if (gen is IAccessor) {

glib/Marshaller.cs

@@ -463,6 +463,39 @@ namespace GLib {
 
 			return result;
 		}
+
+		public static T[] StructArrayFromNullTerminatedIntPtr<T> (IntPtr array)
+		{
+			var res = new List<T> ();
+			IntPtr current = array;
+			T currentStruct = default(T);
+
+			while (current != IntPtr.Zero) {
+				Marshal.PtrToStructure (current, currentStruct);
+				res.Add (currentStruct);
+				current = (IntPtr) ((long)current + Marshal.SizeOf (typeof (T)));
+			}
+
+			return res.ToArray ();
+		}
+
+		public static IntPtr StructArrayToNullTerminatedStructArrayIntPtr<T> (T[] InputArray)
+		{
+			int intPtrSize = Marshal.SizeOf (typeof (IntPtr));
+			IntPtr mem = Marshal.AllocHGlobal ((InputArray.Length + 1) * intPtrSize);
+
+			for (int i = 0; i < InputArray.Length; i++) {
+				IntPtr structPtr = Marshal.AllocHGlobal (Marshal.SizeOf (typeof (T)));
+				Marshal.StructureToPtr (InputArray[i], structPtr, false);
+				// jump to next pointer
+				Marshal.WriteIntPtr (mem, structPtr);
+				mem = (IntPtr) ((long)mem + intPtrSize);
+			}
+			// null terminate
+			Marshal.WriteIntPtr (mem, IntPtr.Zero);
+
+			return mem;
+		}
 	}
 }