From 26142a99ca6e5646257271be1a02e2afbe3070a8 Mon Sep 17 00:00:00 2001
From: Mike Kestner <mkestner@gmail.com>
Date: Thu, 4 Oct 2001 23:27:19 +0000
Subject: [PATCH] 2001-10-04  Mike Kestner <mkestner@speakeasy.net>

	* glib/SimpleSignal.cs : Reworked to parallel SimpleEvent.

svn path=/trunk/gtk-sharp/; revision=1084
---
 ChangeLog            |  4 ++
 glib/SimpleSignal.cs | 97 ++++++++++++++++++++++++++++++--------------
 2 files changed, 70 insertions(+), 31 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index c36ff9a65..3ea9d025e 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+2001-10-04  Mike Kestner <mkestner@speakeasy.net>
+
+	* glib/SimpleSignal.cs : Reworked to parallel SimpleEvent.
+
 2001-10-04  Mike Kestner <mkestner@speakeasy.net>
 
 	* gtk/Widget.cs : Implemented all the bool, string, and int props.
diff --git a/glib/SimpleSignal.cs b/glib/SimpleSignal.cs
index 4d8dbc375..d4083ca68 100644
--- a/glib/SimpleSignal.cs
+++ b/glib/SimpleSignal.cs
@@ -7,6 +7,7 @@
 
 namespace GLib {
 	using System;
+	using System.Collections;
 	using System.Runtime.InteropServices;
 	using GLib;
 
@@ -19,7 +20,7 @@ namespace GLib {
 	///	specific data.
 	/// </remarks>
 
-	public delegate void SimpleDelegate (IntPtr obj, String name);
+	public delegate void SimpleDelegate (IntPtr obj, int key);
 
 	/// <summary>
 	///	SimpleSignal Class
@@ -31,47 +32,81 @@ namespace GLib {
 
 	public class SimpleSignal {
 
-		private static int _RefCount = 0;
+		// A counter used to produce unique keys for instances.
+		private static int _NextKey = 0;
+
+		// Hashtable containing refs to all current instances.
+		private static Hashtable _Instances = new Hashtable ();
+
+		// locals to create and pin the shared delegate.
 		private static SimpleDelegate _Delegate;
 		private static GCHandle _GCHandle;
 
-		private static void SimpleCallback(IntPtr obj, String name)
+		// Shared delegate that relays events to registered handlers.
+		private static void SimpleCallback(IntPtr obj, int inst_key)
 		{
-			Object o = Object.GetObject(obj);
-			EventHandler eh = (EventHandler) o.Events[name];
-			if (eh != null)
-			{
-				eh(o, EventArgs.Empty);
-			}
+			if (!_Instances.Contains (inst_key))
+				throw new Exception ("Unexpected signal key");
+
+			SimpleSignal ss = (SimpleSignal) _Instances [inst_key];
+			EventArgs args = new EventArgs ();
+			ss._handler (ss._obj, args);
 		}
 
-		public static SimpleDelegate Delegate
-		{
-			get
-			{
-				if (_Delegate == null)
-				{
-					_Delegate = new SimpleDelegate(SimpleCallback);
+		// private instance members
+		private GLib.Object _obj;
+		private EventHandler _handler;
+		private int _key;
 
-/* FIXME: Can't do this until a layout attribute is defined for SimpleCallback
- * apparently, since this throws an ArgumentException:Type does not have a 
- * layout attribute.
- *
- *					_GCHandle = GCHandle.Alloc (_Delegate, GCHandleType.Pinned);
- */
-				}
-				_RefCount++;
-				return _Delegate;
+		/// <summary>
+		///	SimpleSignal Constructor
+		/// </summary>
+		///
+		/// <remarks>
+		///	Registers a new event handler for a specified signal.
+		///	A connection to the raw object signal is made which
+		///	causes any events which occur to be relayed to the
+		///	event handler.
+		/// </remarks>
+
+		[DllImport ("gobject-1.3.dll", CharSet=CharSet.Ansi,
+			    CallingConvention=CallingConvention.Cdecl)]
+		static extern void g_signal_connect_data (
+						IntPtr obj, IntPtr name, 
+						SimpleDelegate cb,
+						int key, IntPtr p, int flags);
+
+		public SimpleSignal (GLib.Object obj, IntPtr raw,
+				     String name, EventHandler eh)
+		{
+			if (_Delegate == null) {
+				_Delegate = new SimpleDelegate(SimpleCallback);
+
+				/* FIXME: need layout attribute for 
+				 * SimpleCallback to avoid an exception.
+ 				 * _GCHandle = GCHandle.Alloc (
+				 *	_Delegate, GCHandleType.Pinned);
+ 				 */
 			}
+
+			_key = _NextKey++;
+			_obj = obj;
+			_handler = eh;
+			_Instances [_key] = this;
+
+			g_signal_connect_data (
+				raw, Marshal.StringToHGlobalAnsi (name),
+				_Delegate, _key, new IntPtr (0), 0);
 		}
 
-		public static void Unref()
+		// Destructor needed to release references from the instance
+		// table and unpin the delegate if no refs remain.
+		~SimpleSignal ()
 		{
-			_RefCount--;
-			if (_RefCount < 1)
-			{
-				_RefCount = 0;
-				_GCHandle.Free();
+			_Instances.Remove (_key);
+
+			if (_Instances.Count == 0) {
+				// FIXME: when pin works _GCHandle.Free();
 				_Delegate = null;
 			}
 		}