lisp/progmodes/autoconf.el

   1 ;;; autoconf.el --- mode for editing Autoconf configure.ac files
   2
   3 ;; Copyright (C) 2000-2017 Free Software Foundation, Inc.
   4
   5 ;; Author: Dave Love <fx@gnu.org>
   6 ;; Keywords: languages
   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 ;; Provides fairly minimal font-lock, imenu and indentation support
  26 ;; for editing configure.ac files.  Only Autoconf syntax is processed.
  27 ;; There is no attempt to deal with shell text -- probably that will
  28 ;; always lose.
  29
  30 ;; This is specialized for configure.ac files.  It doesn't inherit the
  31 ;; general M4 stuff from M4 mode.
  32
  33 ;; There is also an autoconf-mode.el in existence.  That appears to be
  34 ;; for editing the Autoconf M4 source, rather than configure.ac files.
  35
  36 ;;; Code:
  37
  38 (defvar autoconf-mode-map (make-sparse-keymap))
  39
  40 (defvar autoconf-mode-hook nil
  41   "Hook run by `autoconf-mode'.")
  42
  43 (defconst autoconf-definition-regexp
  44   "A\\(?:H_TEMPLATE\\|C_\\(?:SUBST\\|DEFINE\\(?:_UNQUOTED\\)?\\)\\)(\\[*\\(\\(?:\\sw\\|\\s_\\)+\\)\\]*")
  45
  46 (defvar autoconf-font-lock-keywords
  47   `(("\\_<A[CHMS]_\\(?:\\sw\\|\\s_\\)+" . font-lock-keyword-face)
  48     (,autoconf-definition-regexp
  49      1 font-lock-function-name-face)
  50     ;; Are any other M4 keywords really appropriate for configure.ac,
  51     ;; given that we do `dnl'?
  52     ("changequote" . font-lock-keyword-face)))
  53
  54 (defvar autoconf-mode-syntax-table
  55   (let ((table (make-syntax-table)))
  56     (modify-syntax-entry ?\" "." table)
  57     (modify-syntax-entry ?\n ">" table)
  58     (modify-syntax-entry ?# "<" table)
  59     table))
  60
  61 (defvar autoconf-imenu-generic-expression
  62   (list (list nil autoconf-definition-regexp 1)))
  63
  64 ;; It's not clear how best to implement this.
  65 (defun autoconf-current-defun-function ()
  66   "Function to use for `add-log-current-defun-function' in Autoconf mode.
  67 This version looks back for an AC_DEFINE or AC_SUBST.  It will stop
  68 searching backwards at another AC_... command."
  69   (save-excursion
  70     (skip-syntax-forward "w_" (line-end-position))
  71     (if (re-search-backward autoconf-definition-regexp
  72                             (save-excursion (beginning-of-defun) (point))
  73                             t)
  74         (match-string-no-properties 1))))
  75
  76 ;;;###autoload
  77 (define-derived-mode autoconf-mode prog-mode "Autoconf"
  78   "Major mode for editing Autoconf configure.ac files."
  79   (setq-local parens-require-spaces nil) ; for M4 arg lists
  80   (setq-local defun-prompt-regexp "^[ \t]*A[CM]_\\(\\sw\\|\\s_\\)+")
  81   (setq-local comment-start "dnl ")
  82   ;; We want to avoid matching "dnl" in other text.
  83   (setq-local comment-start-skip "\\(?:\\(\\W\\|^\\)dnl\\|#\\) +")
  84   (setq-local syntax-propertize-function
  85               (syntax-propertize-rules ("\\<dnl\\>" (0 "<"))))
  86   (setq-local font-lock-defaults
  87               `(autoconf-font-lock-keywords nil nil))
  88   (setq-local imenu-generic-expression autoconf-imenu-generic-expression)
  89   (setq-local indent-line-function #'indent-relative)
  90   (setq-local add-log-current-defun-function
  91               #'autoconf-current-defun-function))
  92
  93 (provide 'autoconf-mode)
  94 (provide 'autoconf)
  95
  96 ;;; autoconf.el ends here