lisp/progmodes/asm-mode.el

   1 ;;; asm-mode.el --- mode for editing assembler code
   2
   3 ;; Author: Eric S. Raymond <esr@snark.thyrsus.com>
   4 ;; Last-Modified: 14 Jul 1992
   5 ;; Keywords: tools, languages
   6
   7 ;;      @(#)asm-mode.el 1.6
   8
   9 ;; Copyright (C) 1991 Free Software Foundation, Inc.
  10
  11 ;; This file is part of GNU Emacs.
  12
  13 ;; GNU Emacs is free software; you can redistribute it and/or modify
  14 ;; it under the terms of the GNU General Public License as published by
  15 ;; the Free Software Foundation; either version 1, or (at your option)
  16 ;; any later version.
  17
  18 ;; GNU Emacs is distributed in the hope that it will be useful,
  19 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  20 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  21 ;; GNU General Public License for more details.
  22
  23 ;; You should have received a copy of the GNU General Public License
  24 ;; along with GNU Emacs; see the file COPYING.  If not, write to
  25 ;; the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
  26
  27 ;;; Commentary:
  28
  29 ;; This mode was written by Eric S. Raymond <esr@snark.thyrsus.com>,
  30 ;; inspired by an earlier asm-mode by Martin Neitzel.
  31
  32 ;; This minor mode is based on text mode.  It defines a private abbrev table
  33 ;; that can be used to save abbrevs for assembler mnemonics.  It binds just
  34 ;; five keys:
  35 ;;
  36 ;;      TAB             tab to next tab stop
  37 ;;      :               outdent preceding label, tab to tab stop
  38 ;;      ;               place or move comment
  39 ;;      C-j, C-m        newline and tab to tab stop
  40 ;;
  41 ;; Code is indented to the first tab stop level.
  42 ;; The ; key inserts copies of the value of asm-comment-char at an
  43 ;; appropriate spot.
  44
  45 ;; This mode runs two hooks:
  46 ;;   1) An asm-set-comment-hook before the part of the initialization
  47 ;; depending on asm-comment-char, and
  48 ;;   2) an asm-mode-hook at the end of initialization.
  49
  50 ;;; Code:
  51
  52 (defvar asm-comment-char ?;
  53   "*The comment-start character assumed by asm-mode.")
  54
  55 (defvar asm-mode-syntax-table nil
  56   "Syntax table used while in asm mode.")
  57
  58 (defvar asm-mode-abbrev-table nil
  59   "Abbrev table used while in asm mode.")
  60 (define-abbrev-table 'asm-mode-abbrev-table ())
  61
  62 (defvar asm-mode-map nil
  63   "Keymap for asm-mode")
  64
  65 (if asm-mode-map
  66     nil
  67   (setq asm-mode-map (make-sparse-keymap))
  68   (define-key asm-mode-map ";"          'asm-comment)
  69   (define-key asm-mode-map ":"          'asm-colon)
  70   (define-key asm-mode-map "\C-i"       'tab-to-tab-stop)
  71   (define-key asm-mode-map "\C-j"       'asm-newline)
  72   (define-key asm-mode-map "\C-m"       'asm-newline)
  73   )
  74
  75 (defvar asm-code-level-empty-comment-pattern nil)
  76 (defvar asm-flush-left-empty-comment-pattern nil)
  77 (defvar asm-inline-empty-comment-pattern nil)
  78
  79 ;;;###autoload
  80 (defun asm-mode ()
  81   "Major mode for editing typical assembler code.
  82 Features a private asm-mode-abbrev-table and the following bindings:
  83
  84 \\[asm-colon]\toutdent a preceding label, tab to next tab stop.
  85 \\[tab-to-tab-stop]\ttab to next tab stop.
  86 \\[asm-newline]\tnewline, then tab to next tab stop.
  87 \\[asm-comment]\tsmart placement of assembler comments.
  88
  89 The character used for making comments is set by the variable
  90 asm-comment-char (which defaults to ?;).  You may want to set this
  91 appropriately for the assembler on your machine in defaults.el.
  92
  93 Alternatively, you may set this variable in asm-set-comment-hook, which is
  94 called near the beginning of mode initialization.
  95
  96 Turning on asm-mode calls the value of the variable asm-mode-hook,
  97 if that value is non-nil, at the end of initialization.
  98
  99 Special commands:\\{asm-mode-map}
 100 "
 101   (interactive)
 102   (kill-all-local-variables)
 103   (use-local-map asm-mode-map)
 104   (setq mode-name "Assembler")
 105   (setq major-mode 'asm-mode)
 106   (setq local-abbrev-table asm-mode-abbrev-table)
 107   (make-local-variable 'asm-mode-syntax-table)
 108   (setq asm-mode-syntax-table (make-syntax-table))
 109   (set-syntax-table asm-mode-syntax-table)
 110   (run-hooks 'asm-mode-set-comment-hook)
 111   (modify-syntax-entry  asm-comment-char
 112                         "<" asm-mode-syntax-table)
 113   (modify-syntax-entry  ?\n
 114                          ">" asm-mode-syntax-table)
 115   (let ((cs (regexp-quote (char-to-string asm-comment-char))))
 116     (make-local-variable 'comment-start)
 117     (setq comment-start (concat cs " "))
 118     (make-local-variable 'comment-start-skip)
 119     (setq comment-start-skip (concat cs "+[ \t]*"))
 120     (setq asm-inline-empty-comment-pattern (concat "^.+" cs "+ *$"))
 121     (setq asm-code-level-empty-comment-pattern (concat "^[\t ]+" cs cs " *$"))
 122     (setq asm-flush-left-empty-comment-pattern (concat "^" cs cs cs " *$"))
 123     )
 124   (make-local-variable 'comment-end)
 125   (setq comment-end "")
 126   (make-local-variable 'comment-column)
 127   (setq comment-column 32)
 128   (auto-fill-mode 1)
 129   (setq fill-prefix "\t")
 130   (run-hooks 'asm-mode-hook)
 131   )
 132
 133 \f
 134 (defun asm-colon ()
 135   "Insert a colon; if it follows a label, delete the label's indentation."
 136   (interactive)
 137   (save-excursion
 138     (beginning-of-line)
 139     (if (looking-at "[ \t]+\\(\\sw\\|\\s_\\)+$")
 140         (delete-horizontal-space)))
 141   (insert ":")
 142   (tab-to-tab-stop)
 143   )
 144
 145 (defun asm-newline ()
 146   "Insert LFD + fill-prefix, to bring us back to code-indent level."
 147   (interactive)
 148   (if (eolp) (delete-horizontal-space))
 149   (insert "\n")
 150   (tab-to-tab-stop)
 151   )
 152
 153 (defun asm-line-matches (pattern &optional withcomment)
 154   (save-excursion
 155     (beginning-of-line)
 156     (looking-at pattern)))
 157
 158 (defun asm-pop-comment-level ()
 159   ;; Delete an empty comment ending current line.  Then set up for a new one,
 160   ;; on the current line if it was all comment, otherwise above it
 161   (end-of-line)
 162   (delete-horizontal-space)
 163   (while (= (preceding-char) asm-comment-char)
 164     (delete-backward-char 1))
 165   (delete-horizontal-space)
 166   (if (bolp)
 167       nil
 168     (beginning-of-line)
 169     (open-line 1))
 170   )
 171
 172
 173 (defun asm-comment ()
 174   "Convert an empty comment to a `larger' kind, or start a new one.
 175 These are the known comment classes:
 176
 177    1 -- comment to the right of the code (at the comment-column)
 178    2 -- comment on its own line, indented like code
 179    3 -- comment on its own line, beginning at the left-most column.
 180
 181 Suggested usage:  while writing your code, trigger asm-comment
 182 repeatedly until you are satisfied with the kind of comment."
 183   (interactive)
 184   (cond
 185
 186    ;; Blank line?  Then start comment at code indent level.
 187    ((asm-line-matches "^[ \t]*$")
 188     (delete-horizontal-space)
 189     (tab-to-tab-stop)
 190     (insert asm-comment-char comment-start))
 191
 192    ;; Nonblank line with no comment chars in it?
 193    ;; Then start a comment at the current comment column
 194    ((asm-line-matches (format "^[^%c]+$" asm-comment-char))
 195     (indent-for-comment))
 196
 197    ;; Flush-left comment present?  Just insert character.
 198    ((asm-line-matches asm-flush-left-empty-comment-pattern)
 199     (insert asm-comment-char))
 200
 201    ;; Empty code-level comment already present?
 202    ;; Then start flush-left comment, on line above if this one is nonempty.
 203    ((asm-line-matches asm-code-level-empty-comment-pattern)
 204     (asm-pop-comment-level)
 205     (insert asm-comment-char asm-comment-char comment-start))
 206
 207    ;; Empty comment ends line?
 208    ;; Then make code-level comment, on line above if this one is nonempty.
 209    ((asm-line-matches asm-inline-empty-comment-pattern)
 210     (asm-pop-comment-level)
 211     (tab-to-tab-stop)
 212     (insert asm-comment-char comment-start))
 213
 214    ;; If all else fails, insert character
 215    (t
 216     (insert asm-comment-char))
 217
 218    )
 219   (end-of-line))
 220
 221 ;;; asm-mode.el ends here