| ------------------------------------------------------------------------------ |
| -- -- |
| -- 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) 2001-2023, 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; |
