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2 -- --
3 -- GNAT RUN-TIME COMPONENTS --
4 -- --
5 -- S Y S T E M . M E M O R Y _ C O P Y --
6 -- --
7 -- S p e c --
8 -- --
9 -- Copyright (C) 2001-2005 Free Software Foundation, Inc. --
10 -- --
11 -- This specification is derived from the Ada Reference Manual for use with --
12 -- GNAT. The copyright notice above, and the license provisions that follow --
13 -- apply solely to the contents of the part following the private keyword. --
14 -- --
15 -- GNAT is free software; you can redistribute it and/or modify it under --
16 -- terms of the GNU General Public License as published by the Free Soft- --
17 -- ware Foundation; either version 2, or (at your option) any later ver- --
18 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
19 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
20 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
21 -- for more details. You should have received a copy of the GNU General --
22 -- Public License distributed with GNAT; see file COPYING. If not, write --
23 -- to the Free Software Foundation, 51 Franklin Street, Fifth Floor, --
24 -- Boston, MA 02110-1301, USA. --
25 -- --
26 -- As a special exception, if other files instantiate generics from this --
27 -- unit, or you link this unit with other files to produce an executable, --
28 -- this unit does not by itself cause the resulting executable to be --
29 -- covered by the GNU General Public License. This exception does not --
30 -- however invalidate any other reasons why the executable file might be --
31 -- covered by the GNU Public License. --
32 -- --
33 -- GNAT was originally developed by the GNAT team at New York University. --
34 -- Extensive contributions were provided by Ada Core Technologies Inc. --
35 -- --
36 ------------------------------------------------------------------------------
38 -- This package provides general block copy mechanisms analogous to those
39 -- provided by the C routines memcpy and memmove allowing for copies with
40 -- and without possible overlap of the operands.
42 -- The idea is to allow a configurable run-time to provide this capability
43 -- for use by the compiler without dragging in C-run time routines.
45 with System.CRTL;
46 -- The above with is contrary to the intent ???
48 package System.Memory_Copy is
49 pragma Preelaborate;
51 procedure memcpy (S1 : Address; S2 : Address; N : System.CRTL.size_t)
52 renames System.CRTL.memcpy;
53 -- Copies N storage units from area starting at S2 to area starting
54 -- at S1 without any check for buffer overflow. The memory areas
55 -- must not overlap, or the result of this call is undefined.
57 procedure memmove (S1 : Address; S2 : Address; N : System.CRTL.size_t)
58 renames System.CRTL.memmove;
59 -- Copies N storage units from area starting at S2 to area starting
60 -- at S1 without any check for buffer overflow. The difference between
61 -- this memmove and memcpy is that with memmove, the storage areas may
62 -- overlap (forwards or backwards) and the result is correct (i.e. it
63 -- is as if S2 is first moved to a temporary area, and then this area
64 -- is copied to S1 in a separate step).
66 -- In the standard library, these are just interfaced to the C routines.
67 -- But in the HI-E (high integrity version) they may be reprogrammed to
68 -- meet certification requirements (and marked High_Integrity).
70 -- Note that in high integrity mode these routines are by default not
71 -- available, and the HI-E compiler will as a result generate implicit
72 -- loops (which will violate the restriction No_Implicit_Loops).
74 end System.Memory_Copy;