lisp/textmodes/dns-mode.el

   1 ;;; dns-mode.el --- a mode for viewing/editing Domain Name System master files
   2
   3 ;; Copyright (C) 2000-2001, 2004-2013 Free Software Foundation, Inc.
   4
   5 ;; Author: Simon Josefsson <simon@josefsson.org>
   6 ;; Keywords: DNS master zone file SOA comm
   7
   8 ;; This file is part of GNU Emacs.
   9
  10 ;; GNU Emacs is free software: you can redistribute it and/or modify
  11 ;; it under the terms of the GNU General Public License as published by
  12 ;; the Free Software Foundation, either version 3 of the License, or
  13 ;; (at your option) any later version.
  14
  15 ;; GNU Emacs is distributed in the hope that it will be useful,
  16 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  17 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18 ;; GNU General Public License for more details.
  19
  20 ;; You should have received a copy of the GNU General Public License
  21 ;; along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.
  22
  23 ;;; Commentary:
  24
  25 ;; Use M-x dns-mode RET to invoke in master files.
  26 ;;
  27 ;; C-c C-s  Increment SOA serial.
  28 ;;          Understands YYYYMMDDNN, Unix time, and serial number formats,
  29 ;;          and complains if it fail to find SOA serial.
  30
  31 ;;; References:
  32
  33 ;; RFC 1034, "DOMAIN NAMES - CONCEPTS AND FACILITIES", P. Mockapetris.
  34 ;; RFC 1035, "DOMAIN NAMES - IMPLEMENTATION AND SPECIFICATION", P. Mockapetris.
  35
  36 ;;; Release history:
  37
  38 ;; 2004-09-11  Posted on gnu.emacs.sources.
  39 ;; 2004-09-13  Ported to XEmacs.
  40 ;; 2004-09-14  Installed in Emacs CVS.
  41
  42 ;;; Code:
  43
  44 (defgroup dns-mode nil
  45   "DNS master file mode configuration."
  46   :group 'data)
  47
  48 (defconst dns-mode-classes '("IN" "CS" "CH" "HS")
  49   "List of strings with known DNS classes.")
  50
  51 (defconst dns-mode-types '("A" "NS" "MD" "MF" "CNAME" "SOA" "MB" "MG" "MR"
  52                            "NULL" "WKS" "PTR" "HINFO" "MINFO" "MX" "TXT"
  53                            "RP" "AFSDB" "X25" "ISDN" "RT" "NSAP" "NSAP"
  54                            "SIG" "KEY" "PX" "GPOS" "AAAA" "LOC" "NXT"
  55                            "EID" "NIMLOC" "SRV" "ATMA" "NAPTR" "KX" "CERT"
  56                            "A6" "DNAME" "SINK" "OPT" "APL" "DS" "SSHFP"
  57                            "RRSIG" "NSEC" "DNSKEY" "UINFO" "UID" "GID"
  58                            "UNSPEC" "TKEY" "TSIG" "IXFR" "AXFR" "MAILB"
  59                            "MAILA")
  60   "List of strings with known DNS types.")
  61
  62 ;; Font lock.
  63
  64 (defvar dns-mode-control-entity-face 'font-lock-keyword-face
  65   "Name of face used for control entities, e.g. $ORIGIN.")
  66
  67 (defvar dns-mode-bad-control-entity-face 'font-lock-warning-face
  68   "Name of face used for non-standard control entities, e.g. $FOO.")
  69
  70 (defvar dns-mode-type-face 'font-lock-type-face
  71   "Name of face used for DNS types, e.g., SOA.")
  72
  73 (defvar dns-mode-class-face 'font-lock-constant-face
  74   "Name of face used for DNS classes, e.g., IN.")
  75
  76 (defcustom dns-mode-font-lock-keywords
  77   `(("^$ORIGIN" 0 ,dns-mode-control-entity-face)
  78     ("^$INCLUDE" 0 ,dns-mode-control-entity-face)
  79     ("^$[a-z0-9A-Z]+" 0 ,dns-mode-bad-control-entity-face)
  80     (,(regexp-opt dns-mode-classes) 0 ,dns-mode-class-face)
  81     (,(regexp-opt dns-mode-types) 0 ,dns-mode-type-face))
  82   "Font lock keywords used to highlight text in DNS master file mode."
  83   :type 'sexp
  84   :group 'dns-mode)
  85
  86 (defcustom dns-mode-soa-auto-increment-serial t
  87   "Whether to increment the SOA serial number automatically.
  88
  89 If this variable is t, the serial number is incremented upon each save of
  90 the file.  If it is `ask', Emacs asks for confirmation whether it should
  91 increment the serial upon saving.  If nil, serials must be incremented
  92 manually with \\[dns-mode-soa-increment-serial]."
  93   :type '(choice (const :tag "Always" t)
  94                  (const :tag "Ask" ask)
  95                  (const :tag "Never" nil))
  96   :group 'dns-mode)
  97
  98 ;; Syntax table.
  99
 100 (defvar dns-mode-syntax-table
 101   (let ((table (make-syntax-table)))
 102     (modify-syntax-entry ?\; "<   " table)
 103     (modify-syntax-entry ?\n ">   " table)
 104     table)
 105   "Syntax table in use in DNS master file buffers.")
 106
 107 ;; Keymap.
 108
 109 (defvar dns-mode-map
 110   (let ((map (make-sparse-keymap)))
 111     (define-key map "\C-c\C-s" 'dns-mode-soa-increment-serial)
 112     map)
 113   "Keymap for DNS master file mode.")
 114
 115 ;; Menu.
 116
 117 (defvar dns-mode-menu nil
 118   "Menubar used in DNS master file mode.")
 119
 120 (easy-menu-define dns-mode-menu dns-mode-map
 121   "DNS Menu."
 122   '("DNS"
 123     ["Increment SOA serial" dns-mode-soa-increment-serial t]))
 124
 125 ;; Mode.
 126
 127 ;;;###autoload
 128 (define-derived-mode dns-mode text-mode "DNS"
 129   "Major mode for viewing and editing DNS master files.
 130 This mode is inherited from text mode.  It add syntax
 131 highlighting, and some commands for handling DNS master files.
 132 Its keymap inherits from `text-mode' and it has the same
 133 variables for customizing indentation.  It has its own abbrev
 134 table and its own syntax table.
 135
 136 Turning on DNS mode runs `dns-mode-hook'."
 137   (set (make-local-variable 'comment-start) ";")
 138   (set (make-local-variable 'comment-end) "")
 139   (set (make-local-variable 'comment-start-skip) ";+ *")
 140   (unless (featurep 'xemacs)
 141     (set (make-local-variable 'font-lock-defaults)
 142          '(dns-mode-font-lock-keywords nil nil ((?_ . "w")))))
 143   (add-hook 'before-save-hook 'dns-mode-soa-maybe-increment-serial
 144             nil t)
 145   (easy-menu-add dns-mode-menu dns-mode-map))
 146
 147 ;;;###autoload (defalias 'zone-mode 'dns-mode)
 148
 149 ;; Tools.
 150
 151 ;;;###autoload
 152 (defun dns-mode-soa-increment-serial ()
 153   "Locate SOA record and increment the serial field."
 154   (interactive)
 155   (save-excursion
 156     (goto-char (point-min))
 157     (unless (re-search-forward
 158              (concat "^\\(\\(\\([^ \t]+[ \t]+\\)?[^ \t]+"
 159                      "[ \t]+\\)?[^ \t]+[ \t]+\\)?SOA") nil t)
 160       (error "Cannot locate SOA record"))
 161     (if (re-search-forward (concat "\\<\\("
 162                                    ;; year
 163                                    "\\(198\\|199\\|20[0-9]\\)[0-9]"
 164                                    ;; month
 165                                    "\\(0[0-9]\\|10\\|11\\|12\\)"
 166                                    ;; day
 167                                    "\\([012][0-9]\\|30\\|31\\)"
 168                                    ;; counter
 169                                    "\\([0-9]\\{1,3\\}\\)"
 170                                    "\\)\\>")
 171                            nil t)
 172         ;; YYYYMMDDIII format, one to three I's.
 173         (let* ((serial (match-string 1))
 174                (counterstr (match-string 5))
 175                (counter (string-to-number counterstr))
 176                (now (format-time-string "%Y%m%d"))
 177                (nowandoldserial (concat now counterstr)))
 178           (if (string< serial nowandoldserial)
 179               (let ((new (format "%s00" now)))
 180                 (replace-match new nil nil nil 1)
 181                 (message "Replaced old serial %s with %s" serial new))
 182             (if (string= serial nowandoldserial)
 183                 (let ((new (format (format "%%s%%0%dd" (length counterstr))
 184                                    now (1+ counter))))
 185                   (replace-match new nil nil nil 1)
 186                   (message "Replaced old serial %s with %s" serial new))
 187               (error "Current SOA serial is in the future"))))
 188       (if (re-search-forward "\\<\\([0-9]\\{9,10\\}\\)\\>" nil t)
 189           ;; Unix time
 190           (let* ((serial (match-string 1))
 191                  (new (format-time-string "%s")))
 192             (if (not (string< serial new))
 193                 (error "Current SOA serial is in the future")
 194               (replace-match new nil nil nil 1)
 195               (message "Replaced old serial %s with %s" serial new)))
 196         (if (re-search-forward "\\<\\([0-9]+\\)\\>" nil t)
 197             ;; Just any serial number.
 198             (let* ((serial (match-string 1))
 199                    (new (format "%d" (1+ (string-to-number serial)))))
 200               (replace-match new nil nil nil 1)
 201               (message "Replaced old serial %s with %s" serial new))
 202           (error "Cannot locate serial number in SOA record"))))))
 203
 204 (defun dns-mode-soa-maybe-increment-serial ()
 205   "Increment SOA serial if needed.
 206
 207 This function is run from `before-save-hook'."
 208   (when (and (buffer-modified-p)
 209              dns-mode-soa-auto-increment-serial
 210              (or (eq dns-mode-soa-auto-increment-serial t)
 211                  (y-or-n-p "Increment SOA serial? ")))
 212     ;; If `dns-mode-soa-increment-serial' signals an error saving will
 213     ;; fail but that probably means that the serial should be fixed to
 214     ;; comply with the RFC anyway! -rfr
 215     (progn (dns-mode-soa-increment-serial)
 216            ;; We return nil in case this is used in write-contents-functions.
 217            nil)))
 218
 219 (provide 'dns-mode)
 220
 221 ;;; dns-mode.el ends here