nagios-mode.el

   1 ;;
   2 ;; nagios-mode, an Emacs mode for Nagios <http://www.nagios.org/>
   3 ;; configuration files.
   4 ;;
   5 ;; Copyright Michael Orlitzky
   6 ;;
   7 ;; http://michael.orlitzky.com/
   8 ;;
   9 ;; This program is free software: you can redistribute it and/or modify
  10 ;; it under the terms of the GNU General Public License as published by
  11 ;; the Free Software Foundation, either version 3 of the License, or
  12 ;; (at your option) any later version.
  13 ;;
  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.
  18 ;;
  19 ;; http://www.fsf.org/licensing/licenses/gpl.html
  20 ;;
  21
  22 (require 'font-lock)
  23 (require 'regexp-opt)
  24
  25
  26 ;; Custom Variables
  27
  28 (defcustom nagios-indent-level 2
  29   "Number of spaces in one indentation (tab)."
  30   :type 'integer :group 'nagios
  31   )
  32
  33
  34
  35 ;; Indentation Voodoo
  36
  37 (defun nagios-indent-line(&optional flag)
  38   "Indents a line, taking nesting into account."
  39   (nagios-indent-to (nagios-calculate-indent))
  40   )
  41
  42
  43
  44 (defun nagios-indent-to(indent-column)
  45   "Indent the current line to column indent-column."
  46   (setq pos (point))
  47   (beginning-of-line)
  48   (setq bol (point))
  49   (setq pos-offset (- pos bol))
  50
  51   (setq first-char-offset
  52         (skip-chars-forward " \t"))
  53
  54   (setq first-char-pos
  55         (+ bol first-char-offset))
  56
  57   (kill-region bol first-char-pos)
  58
  59   (beginning-of-line)
  60
  61   (setq pos-change (- indent-column first-char-offset))
  62   (setq pos-offset (+ pos-offset pos-change))
  63
  64   (if (<= pos-offset indent-column)
  65       (setq pos-offset indent-column))
  66
  67   (while (< 0 indent-column)
  68     (insert " ")
  69     (setq indent-column (- indent-column 1)))
  70
  71   (goto-char (+ bol pos-offset))
  72
  73   )
  74
  75
  76
  77 (defun nagios-in-block()
  78   "Determine if the point is inside of a {} block."
  79
  80   (setq pos (point))
  81
  82   ;; Get the position of the last opening and closing braces, with
  83   ;; respect to the current point
  84   (setq last-opening-brace (re-search-backward "{" nil t))
  85   (goto-char pos)
  86
  87   (setq last-closing-brace (re-search-backward "}" nil t))
  88   (goto-char pos)
  89
  90   ;; If either is nil (not found) just set it to -1, so the comparison
  91   ;; doesn't die.
  92   (if (not last-opening-brace)
  93       (setq last-opening-brace -1))
  94
  95   (if (not last-closing-brace)
  96       (setq last-closing-brace -1))
  97
  98   ;; If the last brace seen in the buffer is an opening brace, we're
  99   ;; in a block. Otherwise, we aren't.
 100   (if (>= last-closing-brace last-opening-brace)
 101       nil
 102     t)
 103   )
 104
 105
 106
 107 (defun nagios-calculate-indent()
 108   "Calculate the level of indentation."
 109   ;; We're either inside a block, or we aren't.
 110
 111   (setq indent 0)
 112
 113   (if (nagios-in-block)
 114       (setq indent nagios-indent-level))
 115
 116   (setq pos (point))
 117   (end-of-line)
 118   (setq eol (point))
 119   (beginning-of-line)
 120   (setq bol (point))
 121
 122   ;; Set the indentation level to 0 if we find either brace on this
 123   ;; line.
 124   (if (re-search-forward "[{}]" eol t)
 125       (setq indent 0))
 126
 127   (goto-char pos)
 128
 129   indent
 130   )
 131
 132
 133
 134 ;; Keymaps
 135
 136 (defun nagios-insert-right-brace-and-indent()
 137   "Insert a '}' character, and indent the line."
 138   (interactive)
 139   (insert "}")
 140   (nagios-indent-line)
 141   )
 142
 143
 144 (defvar nagios-mode-map()
 145   "Keymap used in nagios mode.")
 146
 147 (when (not nagios-mode-map)
 148   (setq nagios-mode-map (make-sparse-keymap))
 149   (define-key nagios-mode-map
 150     (read-kbd-macro "}")
 151     'nagios-insert-right-brace-and-indent)
 152   )
 153
 154
 155
 156 ;; Regular Expression Transformations
 157
 158 (defun regexp-word(regexp)
 159   "Takes a regular expression as an argument, and adds the word boundary condition to the beginning and end of it. Newlines are treated as word boundaries."
 160
 161   ;; This basically joins two expressions in an alternation.
 162   ;; The first allows for a newline followed by our regexp (on
 163   ;; a word boundary), and the second checks for any-non-word
 164   ;; character followed by our regexp.
 165   ;;
 166   ;; I consider neither a hyphen nor an underscore to be a word
 167   ;; boundary for the purpose of syntax highlighting, so I stick
 168   ;; the no-hyphens-or-underscores class on each end of the
 169   ;; expressions.
 170
 171   (concat "\\("
 172           (concat "\\(^\\<\\(" regexp "\\)\\>[^_-]\\)")
 173           "\\|"
 174           (concat "\\([^_-]\\<\\(" regexp "\\)\\>[^_-]\\)")
 175           "\\)")
 176   )
 177
 178
 179 (defun regexp-alt-raw(element-list)
 180   "Takes a list of elements, and returns the string '\\(element1\\|element2...\\)'"
 181
 182   ;; This is necessary since regexp-opt does not accept regular
 183   ;; expressions as arguments. We use regexp-opt when we can, of
 184   ;; course.
 185
 186   (let ((regexp "\\("))
 187     (mapcar (lambda(elem)
 188               (setq regexp (concat regexp "\\(" elem "\\)" "\\|")))
 189             element-list)
 190     (concat (substring regexp 0 -2) ; Cut the last "\\|"
 191             "\\)")
 192     )
 193   )
 194
 195
 196
 197 ;; Syntax Highlighting Patterns
 198
 199 (defconst nagios-comments
 200   (eval-when-compile
 201     (regexp-alt-raw
 202      '("#+.*"
 203        ";+.*")))
 204   )
 205
 206
 207 (defconst nagios-directives
 208   (eval-when-compile
 209     (regexp-opt
 210      '("active_checks_enabled" "address" "alias" "check_command"
 211        "check_freshness" "check_interval" "check_period" "checks_enabled"
 212        "command_line" "command_name" "contact_groups" "contact_name"
 213        "contactgroup_name" "contacts" "dependent_host_name"
 214        "dependent_service_description" "email" "event_handler"
 215        "event_handler_enabled" "execution_failure_criteria"
 216        "failure_prediction_enabled" "first_notification"
 217        "flap_detection_enabled" "freshness_threshold" "friday"
 218        "high_flap_threshold" "host_name" "host_notification_commands"
 219        "host_notification_options" "host_notification_period"
 220        "host_notifications_enabled" "hostgroup_name" "hostgroups"
 221        "is_volatile" "last_notification" "low_flap_threshold"
 222        "max_check_attempts" "members" "monday" "normal_check_interval"
 223        "notes" "notification_failure_criteria"
 224        "notification_interval" "notification_options"
 225        "notification_period" "notifications_enabled"
 226        "obsess_over_service" "pager" "parallelize_check"
 227        "parents" "passive_checks_enabled"
 228        "process_perf_data" "retain_nonstatus_information"
 229        "retain_status_information" "retry_check_interval"
 230        "retry_interval" "saturday" "service_description"
 231        "service_notification_commands" "service_notification_options"
 232        "service_notification_period" "service_notifications_enabled"
 233        "servicegroup_name" "stalking_options"
 234        "sunday" "thursday" "timeperiod_name" "tuesday" "wednesday") t))
 235   )
 236
 237
 238
 239 (defconst nagios-macros
 240   (eval-when-compile
 241     (regexp-alt-raw
 242      '("\\$CONTACT\\(NAME\\|ALIAS\\|EMAIL\\|PAGER\\)\\$"
 243        "\\$HOST\\(NAME\\|ALIAS\\|ADDRESS\\|STATE\\)\\$"
 244        "\\$\\(ARG\\|USER\\)\\([1-9]\\|[1-2][0-9]\\|3[0-2]\\)\\$"
 245        "\\$SERVICE\\(DESC\\|STATE\\)\\$"
 246        "\\$\\(OUTPUT\\|PERFDATA\\|EXECUTIONTIME\\|LATENCY\\)\\$"
 247        "\\$NOTIFICATION\\(TYPE\\|NUMBER\\)\\$"
 248        "\\$\\(\\(SHORT\\)?DATETIME\\|DATE\\|TIME\\|TIMET\\)\\$"
 249        "\\$\\(LASTSTATECHANGE\\|STATETYPE\\)\\$"
 250        "\\$ADMIN\\(EMAIL\\|PAGER\\)\\$"
 251        "\\$\\(SERVICE\\|HOST\\)ATTEMPT\\$")))
 252   )
 253
 254
 255
 256 (defconst nagios-definitions
 257   (eval-when-compile
 258     (regexp-alt-raw
 259      '("define +\\(host\\|service\\|timeperiod\\|contact\\|command\\)"
 260        "define +\\(host\\|contact\\|service\\)group"
 261        "define +\\(service\\|host\\)dependency"
 262        "define +\\(service\\|host\\|hostgroup\\)escalation")))
 263   )
 264
 265
 266
 267 (defconst nagios-special
 268   (eval-when-compile
 269     (regexp-opt
 270      '("name" "register" "use") t))
 271   )
 272
 273
 274
 275 ;; The One True Font Locking Variable
 276
 277 (defvar nagios-font-lock-keywords
 278   (list
 279
 280    ;; This first bit of ugliness allows us to override any
 281    ;; other font-locking with the comment font.
 282    (cons nagios-comments '(0 font-lock-comment-delimiter-face t))
 283
 284    ;; The rest just map regular expressions to font faces.
 285    (cons (regexp-word nagios-directives) font-lock-variable-name-face)
 286    (cons (regexp-word nagios-macros) font-lock-constant-face)
 287    (cons (regexp-word nagios-definitions) font-lock-function-name-face)
 288    (cons (regexp-word nagios-special) font-lock-keyword-face))
 289
 290   "Rules for highlighting Nagios configuration files."
 291   )
 292
 293
 294
 295 ;; Main Mode Function
 296
 297 (defun nagios-mode()
 298   "Major mode for editing Nagios configuration files."
 299
 300   (interactive)
 301
 302   ;; Initializing. This is actually important to cover
 303   ;; up some Emacs stupidity. Font locking won't occur
 304   ;; without it.
 305   (kill-all-local-variables)
 306
 307   ;; Set up indentation handling using the functions
 308   ;; defined earlier.
 309   (make-local-variable 'indent-line-function)
 310   (setq indent-line-function 'nagios-indent-line)
 311
 312   ;; Configure font locking. Set the defaults to something
 313   ;; sensible, defined earlier.
 314   (make-local-variable 'font-lock-defaults)
 315   (setq font-lock-defaults '(nagios-font-lock-keywords nil t))
 316
 317   ;; Keyboard Mapping
 318   (use-local-map nagios-mode-map)
 319
 320   ;; Rock and roll.
 321   (setq mode-name "nagios"
 322         major-mode 'nagios-mode)
 323
 324   ;; I don't /think/ I need to define this before attempting
 325   ;; to run it. Users can define it if they want.
 326   (run-hooks 'nagios-mode-hook)
 327   )
 328
 329
 330 (provide 'nagios-mode)