hard-locale.c

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

   Copyright (C) 1997, 1998, 1999, 2002, 2003 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 2, 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, write to the Free Software Foundation,
   Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */

#if HAVE_CONFIG_H
# include <config.h>
#endif

#include "hard-locale.h"

#if HAVE_LOCALE_H
# include <locale.h>
#endif

#include <stdlib.h>
#include <string.h>

/* Return nonzero if the current CATEGORY locale is hard, i.e. if you
   can't get away with assuming traditional C or POSIX behavior.  */
int
hard_locale (int category)
{
#if ! HAVE_SETLOCALE
  return 0;
#else

  int hard = 1;
  char const *p = setlocale (category, 0);

  if (p)
    {
# if defined __GLIBC__ && 2 <= __GLIBC__
      if (strcmp (p, "C") == 0 || strcmp (p, "POSIX") == 0)
	hard = 0;
# else
      char *locale = malloc (strlen (p) + 1);
      if (locale)
	{
	  strcpy (locale, p);

	  /* 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 = 0;

	  /* Restore the caller's locale.  */
	  setlocale (category, locale);
	  free (locale);
	}
# endif
    }

  return hard;

#endif
}