note description: "[ Accessor to an object with copy semantics. Useful to manipulate fields of an object, or an expanded field of an object without causing any copying. ]" implementation_details: "[ The GC might be moving objects, some of the routines are actually builtin. ]" date: "$Date$" revision: "$Revision$" class REFLECTED_COPY_SEMANTICS_OBJECT inherit REFLECTED_OBJECT REFLECTOR_CONSTANTS create {REFLECTED_OBJECT} make, make_special create {REFLECTED_COPY_SEMANTICS_OBJECT} make_recursive feature {NONE} -- Initialization make (a_enclosing_object: REFLECTED_OBJECT; i: INTEGER) -- Setup a proxy to copy semantics field located at the `i'-th field of `a_enclosing_object'. require i_th_field_is_expanded: a_enclosing_object.is_copy_semantics_field (i) do referring_object := a_enclosing_object referring_physical_offset := a_enclosing_object.field_offset (i) physical_offset := 0 dynamic_type := {ISE_RUNTIME}.dynamic_type_at_offset (object_address, 0) ensure enclosing_object_set: referring_object = a_enclosing_object end make_special (a_enclosing_object: REFLECTED_OBJECT; i: INTEGER) -- Setup a proxy to copy semantics item located at the `i'-th position of special represented by `a_enclosing_object'. require a_enclosing_object_is_special: a_enclosing_object.is_special a_enclosing_object_is_special_reference: a_enclosing_object.is_special_of_reference valid_index: attached {ABSTRACT_SPECIAL} a_enclosing_object.object as l_spec and then l_spec.valid_index (i) i_th_field_is_expanded: a_enclosing_object.is_special_copy_semantics_item (i) do referring_object := a_enclosing_object referring_physical_offset := i * {PLATFORM}.pointer_bytes physical_offset := 0 dynamic_type := {ISE_RUNTIME}.dynamic_type_at_offset (object_address, 0) ensure enclosing_object_set: referring_object = a_enclosing_object end make_recursive (a_enclosing_object: REFLECTED_COPY_SEMANTICS_OBJECT; i: INTEGER) -- Setup a proxy to copy semantics field located at the `i'-th field of `a_enclosing_object'. require i_th_field_is_expanded: a_enclosing_object.is_copy_semantics_field (i) or a_enclosing_object.is_field_statically_expanded (i) do if a_enclosing_object.is_field_statically_expanded (i) then -- Field is expanded. referring_object := a_enclosing_object.referring_object referring_physical_offset := a_enclosing_object.referring_physical_offset physical_offset := a_enclosing_object.physical_offset + a_enclosing_object.field_offset (i) dynamic_type := {ISE_RUNTIME}.dynamic_type_at_offset (object_address, 0) else referring_object := a_enclosing_object referring_physical_offset := a_enclosing_object.field_offset (i) physical_offset := 0 dynamic_type := {ISE_RUNTIME}.dynamic_type_at_offset (object_address, 0) end end feature -- Access object: ANY -- note compiler: no_gc do Result := {ISE_RUNTIME}.reference_field_at (physical_offset, referring_object.object_address, referring_physical_offset) if Result = Void then check object_exists: False then end end end physical_offset: INTEGER -- Actual offset of `object' in `referring_object + referring_physical_offset'. copy_semantics_field (i: INTEGER): REFLECTED_COPY_SEMANTICS_OBJECT -- do create Result.make_recursive (Current, i) end expanded_field (i: INTEGER): REFLECTED_COPY_SEMANTICS_OBJECT -- do create Result.make_recursive (Current, i) end feature {REFLECTED_OBJECT} -- Access object_address: POINTER -- note compiler: no_gc do Result := {ISE_RUNTIME}.raw_reference_field_at (physical_offset, referring_object.object_address, referring_physical_offset) end feature {REFLECTED_COPY_SEMANTICS_OBJECT} -- Access referring_object: REFLECTED_OBJECT -- Enclosing object containing `object' or a reference to `object. referring_physical_offset: INTEGER -- Actual offset in bytes of `object' in `referring_object'. ;note copyright: "Copyright (c) 1984-2020, Eiffel Software and others" license: "Eiffel Forum License v2 (see http://www.eiffel.com/licensing/forum.txt)" source: "[ Eiffel Software 5949 Hollister Ave., Goleta, CA 93117 USA Telephone 805-685-1006, Fax 805-685-6869 Website http://www.eiffel.com Customer support http://support.eiffel.com ]" end