1 ;;; asm-mode.el --- mode for editing assembler code
3 ;; Copyright (C) 1991 Free Software Foundation, Inc.
5 ;; Author: Eric S. Raymond <esr@snark.thyrsus.com>
7 ;; Keywords: tools, languages
9 ;; This file is part of GNU Emacs.
11 ;; GNU Emacs is free software; you can redistribute it and/or modify
12 ;; it under the terms of the GNU General Public License as published by
13 ;; the Free Software Foundation; either version 2, or (at your option)
16 ;; GNU Emacs is distributed in the hope that it will be useful,
17 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
18 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 ;; GNU General Public License for more details.
21 ;; You should have received a copy of the GNU General Public License
22 ;; along with GNU Emacs; see the file COPYING. If not, write to
23 ;; the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
27 ;; This mode was written by Eric S. Raymond <esr@snark.thyrsus.com>,
28 ;; inspired by an earlier asm-mode by Martin Neitzel.
30 ;; This minor mode is based on text mode. It defines a private abbrev table
31 ;; that can be used to save abbrevs for assembler mnemonics. It binds just
34 ;; TAB tab to next tab stop
35 ;; : outdent preceding label, tab to tab stop
36 ;; comment char place or move comment
37 ;; asm-comment-char specifies which character this is;
38 ;; you can use a different character in different
40 ;; C-j, C-m newline and tab to tab stop
42 ;; Code is indented to the first tab stop level.
44 ;; This mode runs two hooks:
45 ;; 1) An asm-mode-set-comment-hook before the part of the initialization
46 ;; depending on asm-comment-char, and
47 ;; 2) an asm-mode-hook at the end of initialization.
51 (defvar asm-comment-char ?;
52 "*The comment-start character assumed by Asm mode.")
54 (defvar asm-mode-syntax-table nil
55 "Syntax table used while in Asm mode.")
57 (defvar asm-mode-abbrev-table nil
58 "Abbrev table used while in Asm mode.")
59 (define-abbrev-table 'asm-mode-abbrev-table ())
61 (defvar asm-mode-map nil
62 "Keymap for Asm mode.")
66 (setq asm-mode-map (make-sparse-keymap))
67 ;; Note that the comment character isn't set up until asm-mode is called.
68 (define-key asm-mode-map ":" 'asm-colon)
69 (define-key asm-mode-map "\C-i" 'tab-to-tab-stop)
70 (define-key asm-mode-map "\C-j" 'asm-newline)
71 (define-key asm-mode-map "\C-m" 'asm-newline)
74 (defconst asm-font-lock-keywords
75 '(("^\\(\\(\\sw\\|\\s_\\)+\\)\\>:?[ \t]*\\(\\sw+\\)?"
76 (1 font-lock-function-name-face) (3 font-lock-keyword-face nil t))
77 ("^\\s +\\(\\(\\sw\\|\\s_\\)+\\)" 1 font-lock-keyword-face))
78 "Additional expressions to highlight in Assembler mode.")
80 (defvar asm-code-level-empty-comment-pattern nil)
81 (defvar asm-flush-left-empty-comment-pattern nil)
82 (defvar asm-inline-empty-comment-pattern nil)
86 "Major mode for editing typical assembler code.
87 Features a private abbrev table and the following bindings:
89 \\[asm-colon]\toutdent a preceding label, tab to next tab stop.
90 \\[tab-to-tab-stop]\ttab to next tab stop.
91 \\[asm-newline]\tnewline, then tab to next tab stop.
92 \\[asm-comment]\tsmart placement of assembler comments.
94 The character used for making comments is set by the variable
95 `asm-comment-char' (which defaults to `?;').
97 Alternatively, you may set this variable in `asm-mode-set-comment-hook',
98 which is called near the beginning of mode initialization.
100 Turning on Asm mode runs the hook `asm-mode-hook' at the end of initialization.
106 (kill-all-local-variables)
107 (setq mode-name "Assembler")
108 (setq major-mode 'asm-mode)
109 (setq local-abbrev-table asm-mode-abbrev-table)
110 (make-local-variable 'font-lock-defaults)
111 (setq font-lock-defaults '(asm-font-lock-keywords))
112 (make-local-variable 'asm-mode-syntax-table)
113 (setq asm-mode-syntax-table (make-syntax-table))
114 (set-syntax-table asm-mode-syntax-table)
116 (run-hooks 'asm-mode-set-comment-hook)
117 ;; Make our own local child of asm-mode-map
118 ;; so we can define our own comment character.
119 (use-local-map (nconc (make-sparse-keymap) asm-mode-map))
120 (local-set-key (vector asm-comment-char) 'asm-comment)
122 (modify-syntax-entry asm-comment-char
123 "<" asm-mode-syntax-table)
124 (modify-syntax-entry ?\n
125 ">" asm-mode-syntax-table)
126 (let ((cs (regexp-quote (char-to-string asm-comment-char))))
127 (make-local-variable 'comment-start)
128 (setq comment-start (concat cs " "))
129 (make-local-variable 'comment-start-skip)
130 (setq comment-start-skip (concat cs "+[ \t]*"))
131 (setq asm-inline-empty-comment-pattern (concat "^.+" cs "+ *$"))
132 (setq asm-code-level-empty-comment-pattern (concat "^[\t ]+" cs cs " *$"))
133 (setq asm-flush-left-empty-comment-pattern (concat "^" cs cs cs " *$"))
135 (make-local-variable 'comment-end)
136 (setq comment-end "")
137 (make-local-variable 'comment-column)
138 (setq comment-column 32)
139 (setq fill-prefix "\t")
140 (run-hooks 'asm-mode-hook))
143 "Insert a colon; if it follows a label, delete the label's indentation."
147 (if (looking-at "[ \t]+\\(\\sw\\|\\s_\\)+$")
148 (delete-horizontal-space)))
153 (defun asm-newline ()
154 "Insert LFD + fill-prefix, to bring us back to code-indent level."
156 (if (eolp) (delete-horizontal-space))
161 (defun asm-line-matches (pattern &optional withcomment)
164 (looking-at pattern)))
166 (defun asm-pop-comment-level ()
167 ;; Delete an empty comment ending current line. Then set up for a new one,
168 ;; on the current line if it was all comment, otherwise above it
170 (delete-horizontal-space)
171 (while (= (preceding-char) asm-comment-char)
172 (delete-backward-char 1))
173 (delete-horizontal-space)
181 (defun asm-comment ()
182 "Convert an empty comment to a `larger' kind, or start a new one.
183 These are the known comment classes:
185 1 -- comment to the right of the code (at the comment-column)
186 2 -- comment on its own line, indented like code
187 3 -- comment on its own line, beginning at the left-most column.
189 Suggested usage: while writing your code, trigger asm-comment
190 repeatedly until you are satisfied with the kind of comment."
194 ;; Blank line? Then start comment at code indent level.
195 ((asm-line-matches "^[ \t]*$")
196 (delete-horizontal-space)
198 (insert asm-comment-char comment-start))
200 ;; Nonblank line with no comment chars in it?
201 ;; Then start a comment at the current comment column
202 ((asm-line-matches (format "^[^%c\n]+$" asm-comment-char))
203 (indent-for-comment))
205 ;; Flush-left comment present? Just insert character.
206 ((asm-line-matches asm-flush-left-empty-comment-pattern)
207 (insert asm-comment-char))
209 ;; Empty code-level comment already present?
210 ;; Then start flush-left comment, on line above if this one is nonempty.
211 ((asm-line-matches asm-code-level-empty-comment-pattern)
212 (asm-pop-comment-level)
213 (insert asm-comment-char asm-comment-char comment-start))
215 ;; Empty comment ends line?
216 ;; Then make code-level comment, on line above if this one is nonempty.
217 ((asm-line-matches asm-inline-empty-comment-pattern)
218 (asm-pop-comment-level)
220 (insert asm-comment-char comment-start))
222 ;; If all else fails, insert character
224 (insert asm-comment-char))
229 ;;; asm-mode.el ends here