trying to rewrite h2

h2/lib2/h3-mm.adb

@@ -0,0 +1,56 @@
+with Ada.Unchecked_Deallocation;
+
+package body H3.MM is
+	procedure Create (R: in out Ref_Counted) is
+	begin
+		Finalize (R);
+		R.Data := new Ref_Counted_Record;
+		--R.Data.Ref_Count := 1;
+		System.Atomic_Counters.Initialize (R.Data.Ref_Count); -- initialize to 1
+	end Create;
+ 
+	procedure Create (R: in out Ref_Counted; V: in Item_Type) is
+	begin
+		Create (R);
+		R.Data.Item := V;
+	end Create;
+
+	function Get_Item_Pointer (R: in out Ref_Counted) return Item_Pointer is
+	begin
+		if R.Data /= null then
+			return R.Data.Item'Access;
+		else
+			return null;
+		end if;
+	end Get_Item_Pointer;
+
+	function Is_Shared (R: in Ref_Counted) return Standard.Boolean is
+	begin
+		return R.Data /= null and then not System.Atomic_Counters.Is_One(R.Data.Ref_Count);
+	end Is_Shared;
+
+	procedure Initialize (R: in out Ref_Counted) is
+	begin
+		R.Data := null;
+	end Initialize;
+
+	procedure Adjust (R: in out Ref_Counted) is
+	begin
+		if R.Data /= null then
+			--R.Data.Ref_Count := R.Data.Ref_Count + 1;
+			System.Atomic_Counters.Increment (R.Data.Ref_Count);
+		end if;
+	end Adjust;
+
+	procedure Finalize (R: in out Ref_Counted) is
+		procedure Dealloc is new Ada.Unchecked_Deallocation(Ref_Counted_Record, Ref_Counted_Pointer);
+	begin
+		if R.Data /= null then	
+			if System.Atomic_Counters.Decrement(R.Data.Ref_Count) then
+				-- The reference count reached 0
+				Dealloc (R.Data); 
+				-- R.DAta must be null here
+			end if;
+		end if;
+	end Finalize;
+end H3.MM;