gnu/dist/grep/intl/textdomain.c

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