1 ;;;; -*- Mode: Lisp; Syntax: ANSI-Common-Lisp; Indent-tabs-mode: NIL -*-
3 ;;; nameservers.lisp --- Nameservers management.
5 ;;; Copyright (C) 2006-2007, Stelian Ionescu <sionescu@common-lisp.net>
7 ;;; This code is free software; you can redistribute it and/or
8 ;;; modify it under the terms of the version 2.1 of
9 ;;; the GNU Lesser General Public License as published by
10 ;;; the Free Software Foundation, as clarified by the
11 ;;; preamble found here:
12 ;;; http://opensource.franz.com/preamble.html
14 ;;; This program is distributed in the hope that it will be useful,
15 ;;; but WITHOUT ANY WARRANTY; without even the implied warranty of
16 ;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 ;;; GNU General Public License for more details.
19 ;;; You should have received a copy of the GNU Lesser General
20 ;;; Public License along with this library; if not, write to the
21 ;;; Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
22 ;;; Boston, MA 02110-1301, USA
24 (in-package :net.sockets
)
26 (defvar *resolv.conf-file
* "/etc/resolv.conf")
28 (defvar *dns-nameservers
* nil
29 "List of the DNS nameservers to use.")
31 (defvar *dns-domain
* nil
32 "The current machine's domain.")
34 (defvar *dns-search-domain
* nil
35 "A domain name to be appended to the name to be searched when
36 the latter does not contain dots.")
38 (defvar *resolvconf-lock
* (bt:make-lock
"/etc/resolv.conf lock"))
40 ;;; Only parses NAMESERVER, DOMAIN and SEARCH directives, for now.
41 (defun parse-/etc
/resolv.conf
(file)
42 (let (nameservers domain search-domain
)
43 (flet ((parse-one-line (tokens)
44 (when (< (length tokens
) 2) (error 'parse-error
))
45 (destructuring-bind (option value
&rest more-values
) tokens
46 (switch (option :test
#'string-equal
)
47 ("nameserver" (ignore-parse-errors
48 (push (ensure-address value
)
50 ("domain" (setf domain value
))
51 ("search" (setf search-domain
(cons value more-values
)))))))
52 (iterate ((tokens (serialize-etc-file file
)))
53 (ignore-errors (parse-one-line tokens
)))
54 (values (nreverse nameservers
) domain search-domain
))))
56 (defun update-dns-parameters (file)
57 (multiple-value-bind (ns domain search
)
58 (parse-/etc
/resolv.conf file
)
59 (setf *dns-nameservers
* (or ns
+ipv4-loopback
+)
60 ;; everything after the first dot
61 *dns-domain
* (cdr (split-sequence #\. domain
:count
2))
62 *dns-search-domain
* search
)))
64 (defvar *resolv.conf-monitor
*
65 (make-instance 'file-monitor
66 :file
*resolv.conf-file
*
67 :update-fn
'update-dns-parameters
68 :lock
*resolvconf-lock
*))