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