intl/textdomain.c

   1 /* Implementation of the textdomain(3) function.
   2    Copyright (C) 1995-1998, 2000, 2001 Free Software Foundation, Inc.
   3
   4    This program is free software; you can redistribute it and/or modify
   5    it under the terms of the GNU General Public License as published by
   6    the Free Software Foundation; either version 2, or (at your option)
   7    any later version.
   8
   9    This program is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12    GNU General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License
  15    along with this program; if not, write to the Free Software Foundation,
  16    Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  17
  18 #ifdef HAVE_CONFIG_H
  19 # include <config.h>
  20 #endif
  21
  22 #include <stdlib.h>
  23 #include <string.h>
  24
  25 #ifdef _LIBC
  26 # include <libintl.h>
  27 #else
  28 # include "libgnuintl.h"
  29 #endif
  30 #include "gettextP.h"
  31
  32 #ifdef _LIBC
  33 /* We have to handle multi-threaded applications.  */
  34 # include <bits/libc-lock.h>
  35 #else
  36 /* Provide dummy implementation if this is outside glibc.  */
  37 # define __libc_rwlock_define(CLASS, NAME)
  38 # define __libc_rwlock_wrlock(NAME)
  39 # define __libc_rwlock_unlock(NAME)
  40 #endif
  41
  42 /* The internal variables in the standalone libintl.a must have different
  43    names than the internal variables in GNU libc, otherwise programs
  44    using libintl.a cannot be linked statically.  */
  45 #if !defined _LIBC
  46 # define _nl_default_default_domain _nl_default_default_domain__
  47 # define _nl_current_default_domain _nl_current_default_domain__
  48 #endif
  49
  50 /* @@ end of prolog @@ */
  51
  52 /* Name of the default text domain.  */
  53 extern const char _nl_default_default_domain[];
  54
  55 /* Default text domain in which entries for gettext(3) are to be found.  */
  56 extern const char *_nl_current_default_domain;
  57
  58
  59 /* Names for the libintl functions are a problem.  They must not clash
  60    with existing names and they should follow ANSI C.  But this source
  61    code is also used in GNU C Library where the names have a __
  62    prefix.  So we have to make a difference here.  */
  63 #ifdef _LIBC
  64 # define TEXTDOMAIN __textdomain
  65 # ifndef strdup
  66 #  define strdup(str) __strdup (str)
  67 # endif
  68 #else
  69 # define TEXTDOMAIN textdomain__
  70 #endif
  71
  72 /* Lock variable to protect the global data in the gettext implementation.  */
  73 __libc_rwlock_define (extern, _nl_state_lock)
  74
  75 /* Set the current default message catalog to DOMAINNAME.
  76    If DOMAINNAME is null, return the current default.
  77    If DOMAINNAME is "", reset to the default of "messages".  */
  78 char *
  79 TEXTDOMAIN (domainname)
  80      const char *domainname;
  81 {
  82   char *new_domain;
  83   char *old_domain;
  84
  85   /* A NULL pointer requests the current setting.  */
  86   if (domainname == NULL)
  87     return (char *) _nl_current_default_domain;
  88
  89   __libc_rwlock_wrlock (_nl_state_lock);
  90
  91   old_domain = (char *) _nl_current_default_domain;
  92
  93   /* If domain name is the null string set to default domain "messages".  */
  94   if (domainname[0] == '\0'
  95       || strcmp (domainname, _nl_default_default_domain) == 0)
  96     {
  97       _nl_current_default_domain = _nl_default_default_domain;
  98       new_domain = (char *) _nl_current_default_domain;
  99     }
 100   else if (strcmp (domainname, old_domain) == 0)
 101     /* This can happen and people will use it to signal that some
 102        environment variable changed.  */
 103     new_domain = old_domain;
 104   else
 105     {
 106       /* If the following malloc fails `_nl_current_default_domain'
 107          will be NULL.  This value will be returned and so signals we
 108          are out of core.  */
 109 #if defined _LIBC || defined HAVE_STRDUP
 110       new_domain = strdup (domainname);
 111 #else
 112       size_t len = strlen (domainname) + 1;
 113       new_domain = (char *) malloc (len);
 114       if (new_domain != NULL)
 115         memcpy (new_domain, domainname, len);
 116 #endif
 117
 118       if (new_domain != NULL)
 119         _nl_current_default_domain = new_domain;
 120     }
 121
 122   /* We use this possibility to signal a change of the loaded catalogs
 123      since this is most likely the case and there is no other easy we
 124      to do it.  Do it only when the call was successful.  */
 125   if (new_domain != NULL)
 126     {
 127       ++_nl_msg_cat_cntr;
 128
 129       if (old_domain != new_domain && old_domain != _nl_default_default_domain)
 130         free (old_domain);
 131     }
 132
 133   __libc_rwlock_unlock (_nl_state_lock);
 134
 135   return new_domain;
 136 }
 137
 138 #ifdef _LIBC
 139 /* Alias for function name in GNU C Library.  */
 140 weak_alias (__textdomain, textdomain);
 141 #endif