1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
5 -- GNAT.SOCKETS.THIN.SOCKET_ERROR_MESSAGE --
9 -- Copyright (C) 2007-2009, AdaCore --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. --
18 -- As a special exception under Section 7 of GPL version 3, you are granted --
19 -- additional permissions described in the GCC Runtime Library Exception, --
20 -- version 3.1, as published by the Free Software Foundation. --
22 -- You should have received a copy of the GNU General Public License and --
23 -- a copy of the GCC Runtime Library Exception along with this program; --
24 -- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see --
25 -- <http://www.gnu.org/licenses/>. --
27 -- GNAT was originally developed by the GNAT team at New York University. --
28 -- Extensive contributions were provided by Ada Core Technologies Inc. --
30 ------------------------------------------------------------------------------
32 -- This is the default implementation of this unit, using the standard C
33 -- library's strerror(3) function. It is used on all platforms except Windows,
34 -- since on that platform socket errno values are distinct from the system
35 -- ones: there is a specific variant of this function in g-socthi-mingw.adb.
37 with Ada.Unchecked_Conversion;
40 separate (GNAT.Sockets.Thin)
41 function Socket_Error_Message
42 (Errno : Integer) return C.Strings.chars_ptr
44 use type Interfaces.C.Strings.chars_ptr;
46 pragma Warnings (Off);
47 function To_Chars_Ptr is
48 new Ada.Unchecked_Conversion
49 (System.Address, Interfaces.C.Strings.chars_ptr);
50 -- On VMS, the compiler warns because System.Address is 64 bits, but
51 -- chars_ptr is 32 bits. It should be safe, though, because strerror
52 -- will return a 32-bit pointer.
55 C_Msg : C.Strings.chars_ptr;
58 C_Msg := To_Chars_Ptr (System.CRTL.strerror (Errno));
59 if C_Msg = C.Strings.Null_Ptr then
60 return Unknown_System_Error;
64 end Socket_Error_Message;