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------------------------------------------------------------------------------
-- --
-- GNAT RUN-TIME COMPONENTS --
-- --
-- S Y S T E M . M E M O R Y _ C O P Y --
-- --
-- S p e c --
-- --
-- Copyright (C) 2001-2022, Free Software Foundation, Inc. --
-- --
-- This specification is derived from the Ada Reference Manual for use with --
-- GNAT. The copyright notice above, and the license provisions that follow --
-- apply solely to the contents of the part following the private keyword. --
-- --
-- GNAT is free software; you can redistribute it and/or modify it under --
-- terms of the GNU General Public License as published by the Free Soft- --
-- ware Foundation; either version 3, or (at your option) any later ver- --
-- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
-- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
-- or FITNESS FOR A PARTICULAR PURPOSE. --
-- --
-- As a special exception under Section 7 of GPL version 3, you are granted --
-- additional permissions described in the GCC Runtime Library Exception, --
-- version 3.1, as published by the Free Software Foundation. --
-- --
-- You should have received a copy of the GNU General Public License and --
-- a copy of the GCC Runtime Library Exception along with this program; --
-- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see --
-- <http://www.gnu.org/licenses/>. --
-- --
-- GNAT was originally developed by the GNAT team at New York University. --
-- Extensive contributions were provided by Ada Core Technologies Inc. --
-- --
------------------------------------------------------------------------------
-- This package provides general block copy mechanisms analogous to those
-- provided by the C routines memcpy and memmove allowing for copies with
-- and without possible overlap of the operands.
-- The idea is to allow a configurable run-time to provide this capability
-- for use by the compiler without dragging in C-run time routines.
with System.CRTL;
-- The above with is contrary to the intent ???
package System.Memory_Copy is
pragma Preelaborate;
procedure memcpy (S1 : Address; S2 : Address; N : System.CRTL.size_t)
renames System.CRTL.memcpy;
-- Copies N storage units from area starting at S2 to area starting
-- at S1 without any check for buffer overflow. The memory areas
-- must not overlap, or the result of this call is undefined.
procedure memmove (S1 : Address; S2 : Address; N : System.CRTL.size_t)
renames System.CRTL.memmove;
-- Copies N storage units from area starting at S2 to area starting
-- at S1 without any check for buffer overflow. The difference between
-- this memmove and memcpy is that with memmove, the storage areas may
-- overlap (forwards or backwards) and the result is correct (i.e. it
-- is as if S2 is first moved to a temporary area, and then this area
-- is copied to S1 in a separate step).
-- In the standard library, these are just interfaced to the C routines.
-- But in the HI-E (high integrity version) they may be reprogrammed to
-- meet certification requirements (and marked High_Integrity).
-- Note that in high integrity mode these routines are by default not
-- available, and the HI-E compiler will as a result generate implicit
-- loops (which will violate the restriction No_Implicit_Loops).
end System.Memory_Copy;