sysdeps/posix/gai_strerror.c

   1 /* Copyright (C) 1997-2016 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Philip Blundell <pjb27@cam.ac.uk>, 1997.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 #include <libintl.h>
  20 #include <netdb.h>
  21 #include <stdint.h>
  22 #include <stdio.h>
  23
  24
  25 #define MSGSTRFIELD(line) MSGSTRFIELD1 (line)
  26 #define MSGSTRFIELD1(line) str##line
  27 static const union msgstr_t
  28 {
  29   struct
  30   {
  31 #define _S(n, s) char MSGSTRFIELD(__LINE__)[sizeof (s)];
  32 #include "gai_strerror-strs.h"
  33 #undef _S
  34   };
  35   char str[0];
  36 } msgstr =
  37   {
  38     {
  39 #define _S(n, s) s,
  40 #include "gai_strerror-strs.h"
  41 #undef _S
  42     }
  43   };
  44 static const struct
  45 {
  46   int16_t code;
  47   uint16_t idx;
  48 } msgidx[] =
  49   {
  50 #define _S(n, s) { n, offsetof (union msgstr_t, MSGSTRFIELD (__LINE__)) },
  51 #include "gai_strerror-strs.h"
  52 #undef _S
  53   };
  54
  55
  56 const char *
  57 gai_strerror (int code)
  58 {
  59   const char *result = "Unknown error";
  60   for (size_t i = 0; i < sizeof (msgidx) / sizeof (msgidx[0]); ++i)
  61     if (msgidx[i].code == code)
  62       {
  63         result = msgstr.str + msgidx[i].idx;
  64         break;
  65       }
  66
  67   return _(result);
  68 }
  69 libc_hidden_def (gai_strerror)