intl/textdomain.c

   1 /* Implementation of the textdomain(3) function.
   2    Copyright (C) 1995-1998, 2000, 2001, 2002 Free Software Foundation, Inc.
   3
   4    This program is free software; you can redistribute it and/or modify it
   5    under the terms of the GNU Library General Public License as published
   6    by 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 GNU
  12    Library General Public License for more details.
  13
  14    You should have received a copy of the GNU Library General Public
  15    License along with this program; if not, write to the Free Software
  16    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
  17    USA.  */
  18
  19 #ifdef HAVE_CONFIG_H
  20 # include <config.h>
  21 #endif
  22
  23 #include <stdlib.h>
  24 #include <string.h>
  25
  26 #ifdef _LIBC
  27 # include <libintl.h>
  28 #else
  29 # include "libgnuintl.h"
  30 #endif
  31 #include "gettextP.h"
  32
  33 #ifdef _LIBC
  34 /* We have to handle multi-threaded applications.  */
  35 # include <bits/libc-lock.h>
  36 #else
  37 /* Provide dummy implementation if this is outside glibc.  */
  38 # define __libc_rwlock_define(CLASS, NAME)
  39 # define __libc_rwlock_wrlock(NAME)
  40 # define __libc_rwlock_unlock(NAME)
  41 #endif
  42
  43 /* The internal variables in the standalone libintl.a must have different
  44    names than the internal variables in GNU libc, otherwise programs
  45    using libintl.a cannot be linked statically.  */
  46 #if !defined _LIBC
  47 # define _nl_default_default_domain libintl_nl_default_default_domain
  48 # define _nl_current_default_domain libintl_nl_current_default_domain
  49 #endif
  50
  51 /* @@ end of prolog @@ */
  52
  53 /* Name of the default text domain.  */
  54 extern const char _nl_default_default_domain[] attribute_hidden;
  55
  56 /* Default text domain in which entries for gettext(3) are to be found.  */
  57 extern const char *_nl_current_default_domain attribute_hidden;
  58
  59
  60 /* Names for the libintl functions are a problem.  They must not clash
  61    with existing names and they should follow ANSI C.  But this source
  62    code is also used in GNU C Library where the names have a __
  63    prefix.  So we have to make a difference here.  */
  64 #ifdef _LIBC
  65 # define TEXTDOMAIN __textdomain
  66 # ifndef strdup
  67 #  define strdup(str) __strdup (str)
  68 # endif
  69 #else
  70 # define TEXTDOMAIN libintl_textdomain
  71 #endif
  72
  73 /* Lock variable to protect the global data in the gettext implementation.  */
  74 __libc_rwlock_define (extern, _nl_state_lock attribute_hidden)
  75
  76 /* Set the current default message catalog to DOMAINNAME.
  77    If DOMAINNAME is null, return the current default.
  78    If DOMAINNAME is "", reset to the default of "messages".  */
  79 char *
  80 TEXTDOMAIN (domainname)
  81      const char *domainname;
  82 {
  83   char *new_domain;
  84   char *old_domain;
  85
  86   /* A NULL pointer requests the current setting.  */
  87   if (domainname == NULL)
  88     return (char *) _nl_current_default_domain;
  89
  90   __libc_rwlock_wrlock (_nl_state_lock);
  91
  92   old_domain = (char *) _nl_current_default_domain;
  93
  94   /* If domain name is the null string set to default domain "messages".  */
  95   if (domainname[0] == '\0'
  96       || strcmp (domainname, _nl_default_default_domain) == 0)
  97     {
  98       _nl_current_default_domain = _nl_default_default_domain;
  99       new_domain = (char *) _nl_current_default_domain;
 100     }
 101   else if (strcmp (domainname, old_domain) == 0)
 102     /* This can happen and people will use it to signal that some
 103        environment variable changed.  */
 104     new_domain = old_domain;
 105   else
 106     {
 107       /* If the following malloc fails `_nl_current_default_domain'
 108          will be NULL.  This value will be returned and so signals we
 109          are out of core.  */
 110 #if defined _LIBC || defined HAVE_STRDUP
 111       new_domain = strdup (domainname);
 112 #else
 113       size_t len = strlen (domainname) + 1;
 114       new_domain = (char *) malloc (len);
 115       if (new_domain != NULL)
 116         memcpy (new_domain, domainname, len);
 117 #endif
 118
 119       if (new_domain != NULL)
 120         _nl_current_default_domain = new_domain;
 121     }
 122
 123   /* We use this possibility to signal a change of the loaded catalogs
 124      since this is most likely the case and there is no other easy we
 125      to do it.  Do it only when the call was successful.  */
 126   if (new_domain != NULL)
 127     {
 128       ++_nl_msg_cat_cntr;
 129
 130       if (old_domain != new_domain && old_domain != _nl_default_default_domain)
 131         free (old_domain);
 132     }
 133
 134   __libc_rwlock_unlock (_nl_state_lock);
 135
 136   return new_domain;
 137 }
 138
 139 #ifdef _LIBC
 140 /* Alias for function name in GNU C Library.  */
 141 weak_alias (__textdomain, textdomain);
 142 #endif