/* hard-locale.c -- Determine whether a locale is hard.

   Copyright (C) 1997-1999, 2002-2004, 2006-2007, 2009-2018 Free Software

   Foundation, Inc.

   This program is free software: you can redistribute it and/or modify

   it under the terms of the GNU General Public License as published by

   the Free Software Foundation; either version 3 of the License, or

   (at your option) any later version.

   This program is distributed in the hope that it will be useful,

   but WITHOUT ANY WARRANTY; without even the implied warranty of

   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License

   along with this program.  If not, see <https://www.gnu.org/licenses/>.  */

#include <config.h>

#include "hard-locale.h"

#include <locale.h>

#include <stdlib.h>

#include <string.h>

#ifdef __GLIBC__

# define GLIBC_VERSION __GLIBC__

#elif defined __UCLIBC__

# define GLIBC_VERSION 2

#else

# define GLIBC_VERSION 0

#endif

/* Return true if the current CATEGORY locale is hard, i.e. if you

   can't get away with assuming traditional C or POSIX behavior.  */

bool

hard_locale (int category)

{

  bool hard = true;

  char const *p = setlocale (category, NULL);

  if (p)

    {

      if (2 <= GLIBC_VERSION)

        {

          if (strcmp (p, "C") == 0 || strcmp (p, "POSIX") == 0)

            hard = false;

        }

      else

        {

          char *locale = strdup (p);

          if (locale)

            {

              /* Temporarily set the locale to the "C" and "POSIX" locales

                 to find their names, so that we can determine whether one

                 or the other is the caller's locale.  */

              if (((p = setlocale (category, "C"))

                   && strcmp (p, locale) == 0)

                  || ((p = setlocale (category, "POSIX"))

                      && strcmp (p, locale) == 0))

                hard = false;

              /* Restore the caller's locale.  */

              setlocale (category, locale);

              free (locale);

            }

        }

    }

  return hard;

}