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 <gnulib/config.h>
  20 # undef VERSION
  21 # undef PACKAGE_VERSION
  22 # undef PACKAGE_TARNAME
  23 # undef PACKAGE_STRING
  24 # include <config.h>
  25 #endif
  26
  27 #include <stdlib.h>
  28 #include <string.h>
  29
  30 #ifdef _LIBC
  31 # include <libintl.h>
  32 #else
  33 # include "libgnuintl.h"
  34 #endif
  35 #include "gettextP.h"
  36
  37 #ifdef _LIBC
  38 /* We have to handle multi-threaded applications.  */
  39 # include <bits/libc-lock.h>
  40 #else
  41 /* Provide dummy implementation if this is outside glibc.  */
  42 # define __libc_rwlock_define(CLASS, NAME)
  43 # define __libc_rwlock_wrlock(NAME)
  44 # define __libc_rwlock_unlock(NAME)
  45 #endif
  46
  47 /* The internal variables in the standalone libintl.a must have different
  48    names than the internal variables in GNU libc, otherwise programs
  49    using libintl.a cannot be linked statically.  */
  50 #if !defined _LIBC
  51 # define _nl_default_default_domain _nl_default_default_domain__
  52 # define _nl_current_default_domain _nl_current_default_domain__
  53 #endif
  54
  55 /* @@ end of prolog @@ */
  56
  57 /* Name of the default text domain.  */
  58 extern const char _nl_default_default_domain[];
  59
  60 /* Default text domain in which entries for gettext(3) are to be found.  */
  61 extern const char *_nl_current_default_domain;
  62
  63
  64 /* Names for the libintl functions are a problem.  They must not clash
  65    with existing names and they should follow ANSI C.  But this source
  66    code is also used in GNU C Library where the names have a __
  67    prefix.  So we have to make a difference here.  */
  68 #ifdef _LIBC
  69 # define TEXTDOMAIN __textdomain
  70 # ifndef strdup
  71 #  define strdup(str) __strdup (str)
  72 # endif
  73 #else
  74 # define TEXTDOMAIN textdomain__
  75 #endif
  76
  77 /* Lock variable to protect the global data in the gettext implementation.  */
  78 __libc_rwlock_define (extern, _nl_state_lock)
  79
  80 /* Set the current default message catalog to DOMAINNAME.
  81    If DOMAINNAME is null, return the current default.
  82    If DOMAINNAME is "", reset to the default of "messages".  */
  83 char *
  84 TEXTDOMAIN (domainname)
  85      const char *domainname;
  86 {
  87   char *new_domain;
  88   char *old_domain;
  89
  90   /* A NULL pointer requests the current setting.  */
  91   if (domainname == NULL)
  92     return (char *) _nl_current_default_domain;
  93
  94   __libc_rwlock_wrlock (_nl_state_lock);
  95
  96   old_domain = (char *) _nl_current_default_domain;
  97
  98   /* If domain name is the null string set to default domain "messages".  */
  99   if (domainname[0] == '\0'
 100       || strcmp (domainname, _nl_default_default_domain) == 0)
 101     {
 102       _nl_current_default_domain = _nl_default_default_domain;
 103       new_domain = (char *) _nl_current_default_domain;
 104     }
 105   else if (strcmp (domainname, old_domain) == 0)
 106     /* This can happen and people will use it to signal that some
 107        environment variable changed.  */
 108     new_domain = old_domain;
 109   else
 110     {
 111       /* If the following malloc fails `_nl_current_default_domain'
 112          will be NULL.  This value will be returned and so signals we
 113          are out of core.  */
 114 #if defined _LIBC || defined HAVE_STRDUP
 115       new_domain = strdup (domainname);
 116 #else
 117       size_t len = strlen (domainname) + 1;
 118       new_domain = (char *) malloc (len);
 119       if (new_domain != NULL)
 120         memcpy (new_domain, domainname, len);
 121 #endif
 122
 123       if (new_domain != NULL)
 124         _nl_current_default_domain = new_domain;
 125     }
 126
 127   /* We use this possibility to signal a change of the loaded catalogs
 128      since this is most likely the case and there is no other easy we
 129      to do it.  Do it only when the call was successful.  */
 130   if (new_domain != NULL)
 131     {
 132       ++_nl_msg_cat_cntr;
 133
 134       if (old_domain != new_domain && old_domain != _nl_default_default_domain)
 135         free (old_domain);
 136     }
 137
 138   __libc_rwlock_unlock (_nl_state_lock);
 139
 140   return new_domain;
 141 }
 142
 143 #ifdef _LIBC
 144 /* Alias for function name in GNU C Library.  */
 145 weak_alias (__textdomain, textdomain);
 146 #endif