intl/textdomain.c

   1 /* Implementation of the textdomain(3) function.
   2    Copyright (C) 1995-1998, 2000, 2001 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 "libgnuintl.h"
  40 #endif
  41 #include "gettextP.h"
  42
  43 #ifdef _LIBC
  44 /* We have to handle multi-threaded applications.  */
  45 # include <bits/libc-lock.h>
  46 #else
  47 /* Provide dummy implementation if this is outside glibc.  */
  48 # define __libc_rwlock_define(CLASS, NAME)
  49 # define __libc_rwlock_wrlock(NAME)
  50 # define __libc_rwlock_unlock(NAME)
  51 #endif
  52
  53 /* The internal variables in the standalone libintl.a must have different
  54    names than the internal variables in GNU libc, otherwise programs
  55    using libintl.a cannot be linked statically.  */
  56 #if !defined _LIBC
  57 # define _nl_default_default_domain _nl_default_default_domain__
  58 # define _nl_current_default_domain _nl_current_default_domain__
  59 #endif
  60
  61 /* @@ end of prolog @@ */
  62
  63 /* Name of the default text domain.  */
  64 extern const char _nl_default_default_domain[];
  65
  66 /* Default text domain in which entries for gettext(3) are to be found.  */
  67 extern const char *_nl_current_default_domain;
  68
  69
  70 /* Names for the libintl functions are a problem.  They must not clash
  71    with existing names and they should follow ANSI C.  But this source
  72    code is also used in GNU C Library where the names have a __
  73    prefix.  So we have to make a difference here.  */
  74 #ifdef _LIBC
  75 # define TEXTDOMAIN __textdomain
  76 # ifndef strdup
  77 #  define strdup(str) __strdup (str)
  78 # endif
  79 #else
  80 # define TEXTDOMAIN textdomain__
  81 #endif
  82
  83 /* Lock variable to protect the global data in the gettext implementation.  */
  84 __libc_rwlock_define (extern, _nl_state_lock)
  85
  86 /* Set the current default message catalog to DOMAINNAME.
  87    If DOMAINNAME is null, return the current default.
  88    If DOMAINNAME is "", reset to the default of "messages".  */
  89 char *
  90 TEXTDOMAIN (domainname)
  91      const char *domainname;
  92 {
  93   char *new_domain;
  94   char *old_domain;
  95
  96   /* A NULL pointer requests the current setting.  */
  97   if (domainname == NULL)
  98     return (char *) _nl_current_default_domain;
  99
 100   __libc_rwlock_wrlock (_nl_state_lock);
 101
 102   old_domain = (char *) _nl_current_default_domain;
 103
 104   /* If domain name is the null string set to default domain "messages".  */
 105   if (domainname[0] == '\0'
 106       || strcmp (domainname, _nl_default_default_domain) == 0)
 107     {
 108       _nl_current_default_domain = _nl_default_default_domain;
 109       new_domain = (char *) _nl_current_default_domain;
 110     }
 111   else if (strcmp (domainname, old_domain) == 0)
 112     /* This can happen and people will use it to signal that some
 113        environment variable changed.  */
 114     new_domain = old_domain;
 115   else
 116     {
 117       /* If the following malloc fails `_nl_current_default_domain'
 118          will be NULL.  This value will be returned and so signals we
 119          are out of core.  */
 120 #if defined _LIBC || defined HAVE_STRDUP
 121       new_domain = strdup (domainname);
 122 #else
 123       size_t len = strlen (domainname) + 1;
 124       new_domain = (char *) malloc (len);
 125       if (new_domain != NULL)
 126         memcpy (new_domain, domainname, len);
 127 #endif
 128
 129       if (new_domain != NULL)
 130         _nl_current_default_domain = new_domain;
 131     }
 132
 133   /* We use this possibility to signal a change of the loaded catalogs
 134      since this is most likely the case and there is no other easy we
 135      to do it.  Do it only when the call was successful.  */
 136   if (new_domain != NULL)
 137     {
 138       ++_nl_msg_cat_cntr;
 139
 140       if (old_domain != new_domain && old_domain != _nl_default_default_domain)
 141         free (old_domain);
 142     }
 143
 144   __libc_rwlock_unlock (_nl_state_lock);
 145
 146   return new_domain;
 147 }
 148
 149 #ifdef _LIBC
 150 /* Alias for function name in GNU C Library.  */
 151 weak_alias (__textdomain, textdomain);
 152 #endif