intl/textdomain.c

   1 /* Implementation of the textdomain(3) function.
   2    Copyright (C) 1995-1998, 2000, 2001, 2002 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, write to the Free
  17    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  18    02111-1307 USA.  */
  19
  20 #ifdef HAVE_CONFIG_H
  21 # include <config.h>
  22 #endif
  23
  24 #include <stdlib.h>
  25 #include <string.h>
  26
  27 #ifdef _LIBC
  28 # include <libintl.h>
  29 #else
  30 # include "libgnuintl.h"
  31 #endif
  32 #include "gettextP.h"
  33
  34 #ifdef _LIBC
  35 /* We have to handle multi-threaded applications.  */
  36 # include <bits/libc-lock.h>
  37 #else
  38 /* Provide dummy implementation if this is outside glibc.  */
  39 # define __libc_rwlock_define(CLASS, NAME)
  40 # define __libc_rwlock_wrlock(NAME)
  41 # define __libc_rwlock_unlock(NAME)
  42 #endif
  43
  44 /* The internal variables in the standalone libintl.a must have different
  45    names than the internal variables in GNU libc, otherwise programs
  46    using libintl.a cannot be linked statically.  */
  47 #if !defined _LIBC
  48 # define _nl_default_default_domain libintl_nl_default_default_domain
  49 # define _nl_current_default_domain libintl_nl_current_default_domain
  50 #endif
  51
  52 /* @@ end of prolog @@ */
  53
  54 /* Name of the default text domain.  */
  55 extern const char _nl_default_default_domain[] attribute_hidden;
  56
  57 /* Default text domain in which entries for gettext(3) are to be found.  */
  58 extern const char *_nl_current_default_domain attribute_hidden;
  59
  60
  61 /* Names for the libintl functions are a problem.  They must not clash
  62    with existing names and they should follow ANSI C.  But this source
  63    code is also used in GNU C Library where the names have a __
  64    prefix.  So we have to make a difference here.  */
  65 #ifdef _LIBC
  66 # define TEXTDOMAIN __textdomain
  67 # ifndef strdup
  68 #  define strdup(str) __strdup (str)
  69 # endif
  70 #else
  71 # define TEXTDOMAIN libintl_textdomain
  72 #endif
  73
  74 /* Lock variable to protect the global data in the gettext implementation.  */
  75 __libc_rwlock_define (extern, _nl_state_lock attribute_hidden)
  76
  77 /* Set the current default message catalog to DOMAINNAME.
  78    If DOMAINNAME is null, return the current default.
  79    If DOMAINNAME is "", reset to the default of "messages".  */
  80 char *
  81 TEXTDOMAIN (domainname)
  82      const char *domainname;
  83 {
  84   char *new_domain;
  85   char *old_domain;
  86
  87   /* A NULL pointer requests the current setting.  */
  88   if (domainname == NULL)
  89     return (char *) _nl_current_default_domain;
  90
  91   __libc_rwlock_wrlock (_nl_state_lock);
  92
  93   old_domain = (char *) _nl_current_default_domain;
  94
  95   /* If domain name is the null string set to default domain "messages".  */
  96   if (domainname[0] == '\0'
  97       || strcmp (domainname, _nl_default_default_domain) == 0)
  98     {
  99       _nl_current_default_domain = _nl_default_default_domain;
 100       new_domain = (char *) _nl_current_default_domain;
 101     }
 102   else if (strcmp (domainname, old_domain) == 0)
 103     /* This can happen and people will use it to signal that some
 104        environment variable changed.  */
 105     new_domain = old_domain;
 106   else
 107     {
 108       /* If the following malloc fails `_nl_current_default_domain'
 109          will be NULL.  This value will be returned and so signals we
 110          are out of core.  */
 111 #if defined _LIBC || defined HAVE_STRDUP
 112       new_domain = strdup (domainname);
 113 #else
 114       size_t len = strlen (domainname) + 1;
 115       new_domain = (char *) malloc (len);
 116       if (new_domain != NULL)
 117         memcpy (new_domain, domainname, len);
 118 #endif
 119
 120       if (new_domain != NULL)
 121         _nl_current_default_domain = new_domain;
 122     }
 123
 124   /* We use this possibility to signal a change of the loaded catalogs
 125      since this is most likely the case and there is no other easy we
 126      to do it.  Do it only when the call was successful.  */
 127   if (new_domain != NULL)
 128     {
 129       ++_nl_msg_cat_cntr;
 130
 131       if (old_domain != new_domain && old_domain != _nl_default_default_domain)
 132         free (old_domain);
 133     }
 134
 135   __libc_rwlock_unlock (_nl_state_lock);
 136
 137   return new_domain;
 138 }
 139
 140 #ifdef _LIBC
 141 /* Alias for function name in GNU C Library.  */
 142 weak_alias (__textdomain, textdomain);
 143 #endif