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."
 160
 161   ;; I consider neither a hyphen nor an underscore to be a word
 162   ;; boundary for the purpose of syntax highlighting.
 163   (concat "[^_-]\\<\\(" regexp "\\)\\>[^_-]")
 164   )
 165
 166
 167 (defun regexp-alt-raw(element-list)
 168   "Takes a list of elements, and returns the string '\\(element1\\|element2...\\)'"
 169
 170   ;; This is necessary since regexp-opt does not accept regular
 171   ;; expressions as arguments. We use regexp-opt when we can, of
 172   ;; course.
 173
 174   (let ((regexp "\\("))
 175     (mapcar (lambda(elem)
 176               (setq regexp (concat regexp "\\(" elem "\\)" "\\|")))
 177             element-list)
 178     (concat (substring regexp 0 -2) ; Cut the last "\\|"
 179             "\\)")
 180     )
 181   )
 182
 183
 184
 185 ;; Syntax Highlighting Patterns
 186
 187 (defconst nagios-comments
 188   (eval-when-compile
 189     (regexp-alt-raw
 190      '("#+.*"
 191        ";+.*")))
 192   )
 193
 194
 195 (defconst nagios-directives
 196   (eval-when-compile
 197     (regexp-opt
 198      '("active_checks_enabled" "address" "alias" "check_command"
 199        "check_freshness" "check_interval" "check_period" "checks_enabled"
 200        "command_line" "command_name" "contact_groups" "contact_name"
 201        "contactgroup_name" "dependent_host_name"
 202        "dependent_service_description" "email" "event_handler"
 203        "event_handler_enabled" "execution_failure_criteria"
 204        "failure_prediction_enabled" "first_notification"
 205        "flap_detection_enabled" "freshness_threshold" "friday"
 206        "high_flap_threshold" "host_name" "host_notification_commands"
 207        "host_notification_options" "host_notification_period"
 208        "hostgroup_name" "hostgroups" "is_volatile" "last_notification"
 209        "low_flap_threshold" "max_check_attempts"
 210        "members" "monday" "normal_check_interval"
 211        "notification_failure_criteria"
 212        "notification_interval" "notification_options"
 213        "notification_period" "notifications_enabled"
 214        "obsess_over_service" "pager" "parallelize_check"
 215        "parents" "passive_checks_enabled"
 216        "process_perf_data" "retain_nonstatus_information"
 217        "retain_status_information" "retry_check_interval"
 218        "retry_interval" "saturday" "service_description"
 219        "service_notification_commands"
 220        "service_notification_options"
 221        "service_notification_period" "stalking_options"
 222        "sunday" "thursday" "timeperiod_name" "tuesday" "wednesday") t))
 223   )
 224
 225
 226
 227 (defconst nagios-macros
 228   (eval-when-compile
 229     (regexp-alt-raw
 230      '("\\$CONTACT\\(NAME\\|ALIAS\\|EMAIL\\|PAGER\\)\\$"
 231        "\\$HOST\\(NAME\\|ALIAS\\|ADDRESS\\|STATE\\)\\$"
 232        "\\$\\(ARG\\|USER\\)\\([1-9]\\|[1-2][0-9]\\|3[0-2]\\)\\$"
 233        "\\$SERVICE\\(DESC\\|STATE\\)\\$"
 234        "\\$\\(OUTPUT\\|PERFDATA\\|EXECUTIONTIME\\|LATENCY\\)\\$"
 235        "\\$NOTIFICATION\\(TYPE\\|NUMBER\\)\\$"
 236        "\\$\\(\\(SHORT\\)?DATETIME\\|DATE\\|TIME\\|TIMET\\)\\$"
 237        "\\$\\(LASTSTATECHANGE\\|STATETYPE\\)\\$"
 238        "\\$ADMIN\\(EMAIL\\|PAGER\\)\\$"
 239        "\\$\\(SERVICE\\|HOST\\)ATTEMPT\\$")))
 240   )
 241
 242
 243
 244 (defconst nagios-definitions
 245   (eval-when-compile
 246     (regexp-alt-raw
 247      '("define +\\(host\\|service\\|timeperiod\\|contact\\|command\\)"
 248        "define +\\(host\\|contact\\)group"
 249        "define +\\(service\\|host\\)dependency"
 250        "define +\\(service\\|host\\|hostgroup\\)escalation")))
 251   )
 252
 253
 254
 255 (defconst nagios-special
 256   (eval-when-compile
 257     (regexp-opt
 258      '("name" "register" "use") t))
 259   )
 260
 261
 262
 263 ;; The One True Font Locking Variable
 264
 265 (defvar nagios-font-lock-keywords
 266   (list
 267
 268    ;; This first bit of ugliness allows us to override any
 269    ;; other font-locking with the comment font.
 270    (cons nagios-comments '(0 font-lock-comment-delimiter-face t))
 271
 272    ;; The rest just map regular expressions to font faces.
 273    (cons (regexp-word nagios-directives) font-lock-variable-name-face)
 274    (cons (regexp-word nagios-macros) font-lock-constant-face)
 275    (cons (regexp-word nagios-definitions) font-lock-function-name-face)
 276    (cons (regexp-word nagios-special) font-lock-keyword-face))
 277
 278   "Rules for highlighting Nagios configuration files."
 279   )
 280
 281
 282
 283 ;; Main Mode Function
 284
 285 (defun nagios-mode()
 286   "Major mode for editing Nagios configuration files."
 287
 288   (interactive)
 289
 290   ;; Initializing. This is actually important to cover
 291   ;; up some Emacs stupidity. Font locking won't occur
 292   ;; without it.
 293   (kill-all-local-variables)
 294
 295   ;; Set up indentation handling using the functions
 296   ;; defined earlier.
 297   (make-local-variable 'indent-line-function)
 298   (setq indent-line-function 'nagios-indent-line)
 299
 300   ;; Configure font locking. Set the defaults to something
 301   ;; sensible, defined earlier.
 302   (make-local-variable 'font-lock-defaults)
 303   (setq font-lock-defaults '(nagios-font-lock-keywords nil t))
 304
 305   ;; Keyboard Mapping
 306   (use-local-map nagios-mode-map)
 307
 308   ;; Rock and roll.
 309   (setq mode-name "nagios"
 310         major-mode 'nagios-mode)
 311
 312   ;; I don't /think/ I need to define this before attempting
 313   ;; to run it. Users can define it if they want.
 314   (run-hooks 'nagios-mode-hook)
 315   )
 316
 317
 318 (provide 'nagios-mode)