/* Implementation of the textdomain(3) function.

   Copyright (C) 1995-2018 Free Software Foundation, Inc.

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

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

   the Free Software Foundation; either version 2.1 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 Lesser General Public License for more details.

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

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

#ifdef HAVE_CONFIG_H

# include <config.h>

#endif

#include <stdlib.h>

#include <string.h>

#include "gettextP.h"

#ifdef _LIBC

# include <libintl.h>

#else

# include "libgnuintl.h"

#endif

/* Handle multi-threaded applications.  */

#ifdef _LIBC

# include <libc-lock.h>

# define gl_rwlock_define __libc_rwlock_define

# define gl_rwlock_wrlock __libc_rwlock_wrlock

# define gl_rwlock_unlock __libc_rwlock_unlock

#else

# include "lock.h"

#endif

/* @@ end of prolog @@ */

/* Names for the libintl functions are a problem.  They must not clash

   with existing names and they should follow ANSI C.  But this source

   code is also used in GNU C Library where the names have a __

   prefix.  So we have to make a difference here.  */

#ifdef _LIBC

# define TEXTDOMAIN __textdomain

# ifndef strdup

#  define strdup(str) __strdup (str)

# endif

#else

# define TEXTDOMAIN libintl_textdomain

#endif

/* Lock variable to protect the global data in the gettext implementation.  */

gl_rwlock_define (extern, _nl_state_lock attribute_hidden)

/* Set the current default message catalog to DOMAINNAME.

   If DOMAINNAME is null, return the current default.

   If DOMAINNAME is "", reset to the default of "messages".  */

char *

TEXTDOMAIN (const char *domainname)

{

  char *new_domain;

  char *old_domain;

  /* A NULL pointer requests the current setting.  */

  if (domainname == NULL)

    return (char *) _nl_current_default_domain;

  gl_rwlock_wrlock (_nl_state_lock);

  old_domain = (char *) _nl_current_default_domain;

  /* If domain name is the null string set to default domain "messages".  */

  if (domainname[0] == '\0'

      || strcmp (domainname, _nl_default_default_domain) == 0)

    {

      _nl_current_default_domain = _nl_default_default_domain;

      new_domain = (char *) _nl_current_default_domain;

    }

  else if (strcmp (domainname, old_domain) == 0)

    /* This can happen and people will use it to signal that some

       environment variable changed.  */

    new_domain = old_domain;

  else

    {

      /* If the following malloc fails `_nl_current_default_domain'

	 will be NULL.  This value will be returned and so signals we

	 are out of core.  */

#if defined _LIBC || defined HAVE_STRDUP

      new_domain = strdup (domainname);

#else

      size_t len = strlen (domainname) + 1;

      new_domain = (char *) malloc (len);

      if (new_domain != NULL)

	memcpy (new_domain, domainname, len);

#endif

      if (new_domain != NULL)

	_nl_current_default_domain = new_domain;

    }

  /* We use this possibility to signal a change of the loaded catalogs

     since this is most likely the case and there is no other easy we

     to do it.  Do it only when the call was successful.  */

  if (new_domain != NULL)

    {

      ++_nl_msg_cat_cntr;

      if (old_domain != new_domain && old_domain != _nl_default_default_domain)

	free (old_domain);

    }

  gl_rwlock_unlock (_nl_state_lock);

  return new_domain;

}

#ifdef _LIBC

/* Alias for function name in GNU C Library.  */

weak_alias (__textdomain, textdomain);

#endif