Implement properly the dispose patternw where possible

svn path=/trunk/mcs/; revision=81575

2 files changed, 24 insertions, 7 deletions

diff --git a/mcs/class/Mono.Cairo/Mono.Cairo/FontFace.cs b/mcs/class/Mono.Cairo/Mono.Cairo/FontFace.cs
index 684bf0f80e7..a7adbd9339a 100644
--- a/mcs/class/Mono.Cairo/Mono.Cairo/FontFace.cs
+++ b/mcs/class/Mono.Cairo/Mono.Cairo/FontFace.cs
@@ -54,11 +54,18 @@ namespace Cairo
 			// font_face here, the programmer must do this with IDisposable.Dispose
 
 			Console.Error.WriteLine ("Programmer forgot to call Dispose on the FontFace");
+			Dispose (false);
 		}
 
 		void IDisposable.Dispose ()
 		{
-			NativeMethods.cairo_font_face_destroy (handle);
+			Dispose (true);
+		}
+
+		protected virtual void Dispose (bool disposing)
+		{
+			if (disposing)
+				NativeMethods.cairo_font_face_destroy (handle);
 			handle = IntPtr.Zero;
 			GC.SuppressFinalize (this);
 		}
diff --git a/mcs/class/Mono.Cairo/Mono.Cairo/Pattern.cs b/mcs/class/Mono.Cairo/Mono.Cairo/Pattern.cs
index a4ee9daa533..80a180ee332 100644
--- a/mcs/class/Mono.Cairo/Mono.Cairo/Pattern.cs
+++ b/mcs/class/Mono.Cairo/Mono.Cairo/Pattern.cs
@@ -76,9 +76,6 @@ namespace Cairo {
 
 		~Pattern ()
 		{
-			lock (patterns){
-				patterns.Remove (this);
-			}
 		}
 		
                 [Obsolete ("Use the SurfacePattern constructor")]
@@ -92,14 +89,27 @@ namespace Cairo {
                         NativeMethods.cairo_pattern_reference (pattern);
                 }
 
-		public void Dispose ()
+		void IDisposable.Dispose ()
+		{
+			Dispose (true);
+		}
+
+		protected virtual void Dispose (bool disposing)
 		{
-			Destroy ();
+			if (disposing)
+				Destroy ();
+			GC.SuppressFinalize (this);
 		}
 		
                 public void Destroy ()
                 {
-                        NativeMethods.cairo_pattern_destroy (pattern);
+			if (pattern != IntPtr.Zero){
+				NativeMethods.cairo_pattern_destroy (pattern);
+				pattern = IntPtr.Zero;
+			}
+			lock (patterns){
+				patterns.Remove (this);
+			}
                 }
 		
 		public Status Status