intl/textdomain.c

   1 /* Implementation of the textdomain(3) function.
   2    Copyright (C) 1995, 1996, 1997, 1998, 2000 Free Software Foundation, Inc.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Library General Public License as
   6    published by the Free Software Foundation; either version 2 of the
   7    License, or (at your option) any later version.
   8
   9    The GNU C Library 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 the GNU C Library; see the file COPYING.LIB.  If not,
  16    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  17    Boston, MA 02111-1307, USA.  */
  18
  19 #ifdef HAVE_CONFIG_H
  20 # include <config.h>
  21 #endif
  22
  23 #if defined STDC_HEADERS || defined _LIBC
  24 # include <stdlib.h>
  25 #endif
  26
  27 #if defined STDC_HEADERS || defined HAVE_STRING_H || defined _LIBC
  28 # include <string.h>
  29 #else
  30 # include <strings.h>
  31 # ifndef memcpy
  32 #  define memcpy(Dst, Src, Num) (bcopy (Src, Dst, Num), (Dst))
  33 # endif
  34 #endif
  35
  36 #ifdef _LIBC
  37 # include <libintl.h>
  38 #else
  39 # include "libgettext.h"
  40 #endif
  41 #include "gettext.h"
  42 #include "gettextP.h"
  43
  44 #ifdef _LIBC
  45 /* We have to handle multi-threaded applications.  */
  46 # include <bits/libc-lock.h>
  47 #else
  48 /* Provide dummy implementation if this is outside glibc.  */
  49 # define __libc_rwlock_define(CLASS, NAME)
  50 # define __libc_rwlock_wrlock(NAME)
  51 # define __libc_rwlock_unlock(NAME)
  52 #endif
  53
  54 /* The internal variables in the standalone libintl.a must have different
  55    names than the internal variables in GNU libc, otherwise programs
  56    using libintl.a cannot be linked statically.  */
  57 #if !defined _LIBC
  58 # define _nl_default_default_domain _nl_default_default_domain__
  59 # define _nl_current_default_domain _nl_current_default_domain__
  60 #endif
  61
  62 /* @@ end of prolog @@ */
  63
  64 /* Name of the default text domain.  */
  65 extern const char _nl_default_default_domain[];
  66
  67 /* Default text domain in which entries for gettext(3) are to be found.  */
  68 extern const char *_nl_current_default_domain;
  69
  70
  71 /* Names for the libintl functions are a problem.  They must not clash
  72    with existing names and they should follow ANSI C.  But this source
  73    code is also used in GNU C Library where the names have a __
  74    prefix.  So we have to make a difference here.  */
  75 #ifdef _LIBC
  76 # define TEXTDOMAIN __textdomain
  77 # ifndef strdup
  78 #  define strdup(str) __strdup (str)
  79 # endif
  80 #else
  81 # define TEXTDOMAIN textdomain__
  82 #endif
  83
  84 /* Lock variable to protect the global data in the gettext implementation.  */
  85 __libc_rwlock_define (extern, _nl_state_lock)
  86
  87 /* Set the current default message catalog to DOMAINNAME.
  88    If DOMAINNAME is null, return the current default.
  89    If DOMAINNAME is "", reset to the default of "messages".  */
  90 char *
  91 TEXTDOMAIN (domainname)
  92      const char *domainname;
  93 {
  94   char *new_domain;
  95   char *old_domain;
  96
  97   /* A NULL pointer requests the current setting.  */
  98   if (domainname == NULL)
  99     return (char *) _nl_current_default_domain;
 100
 101   __libc_rwlock_wrlock (_nl_state_lock);
 102
 103   old_domain = (char *) _nl_current_default_domain;
 104
 105   /* If domain name is the null string set to default domain "messages".  */
 106   if (domainname[0] == '\0'
 107       || strcmp (domainname, _nl_default_default_domain) == 0)
 108     {
 109       _nl_current_default_domain = _nl_default_default_domain;
 110       new_domain = (char *) _nl_current_default_domain;
 111     }
 112   else if (strcmp (domainname, old_domain) == 0)
 113     /* This can happen and people will use it to signal that some
 114        environment variable changed.  */
 115     new_domain = old_domain;
 116   else
 117     {
 118       /* If the following malloc fails `_nl_current_default_domain'
 119          will be NULL.  This value will be returned and so signals we
 120          are out of core.  */
 121 #if defined _LIBC || defined HAVE_STRDUP
 122       new_domain = strdup (domainname);
 123 #else
 124       size_t len = strlen (domainname) + 1;
 125       new_domain = (char *) malloc (len);
 126       if (new_domain != NULL)
 127         memcpy (new_domain, domainname, len);
 128 #endif
 129
 130       if (new_domain != NULL)
 131         _nl_current_default_domain = new_domain;
 132     }
 133
 134   /* We use this possibility to signal a change of the loaded catalogs
 135      since this is most likely the case and there is no other easy we
 136      to do it.  Do it only when the call was successful.  */
 137   if (new_domain != NULL)
 138     {
 139       ++_nl_msg_cat_cntr;
 140
 141       if (old_domain != new_domain && old_domain != _nl_default_default_domain)
 142         free (old_domain);
 143     }
 144
 145   __libc_rwlock_unlock (_nl_state_lock);
 146
 147   return new_domain;
 148 }
 149
 150 #ifdef _LIBC
 151 /* Alias for function name in GNU C Library.  */
 152 weak_alias (__textdomain, textdomain);
 153 #endif