gl/hard-locale.c

   1 /* hard-locale.c -- Determine whether a locale is hard.
   2
   3    Copyright (C) 1997-1999, 2002-2004, 2006-2007, 2009-2024 Free Software
   4    Foundation, Inc.
   5
   6    This file is free software: you can redistribute it and/or modify
   7    it under the terms of the GNU Lesser General Public License as
   8    published by the Free Software Foundation; either version 2.1 of the
   9    License, or (at your option) any later version.
  10
  11    This file is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU Lesser General Public License for more details.
  15
  16    You should have received a copy of the GNU Lesser General Public License
  17    along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
  18
  19 #include <config.h>
  20
  21 #include "hard-locale.h"
  22
  23 #include <locale.h>
  24 #include <stdlib.h>
  25 #include <string.h>
  26
  27 bool
  28 hard_locale (int category)
  29 {
  30   char locale[SETLOCALE_NULL_MAX];
  31
  32   if (setlocale_null_r (category, locale, sizeof (locale)))
  33     return false;
  34
  35   if (!(strcmp (locale, "C") == 0 || strcmp (locale, "POSIX") == 0))
  36     return true;
  37
  38 #if defined __ANDROID__
  39   /* On Android 5.0 or newer, it is possible to set a locale that has the same
  40      name as the "C" locale but in fact uses UTF-8 encoding.  Cf. test case 2 in
  41      <https://lists.gnu.org/archive/html/bug-gnulib/2023-01/msg00141.html>.  */
  42   if (MB_CUR_MAX > 1)
  43     return true;
  44 #endif
  45
  46   return false;
  47 }