1 ;;; view.el --- peruse file or buffer without editing.
3 ;; Copyright (C) 1985, 1989 Free Software Foundation, Inc.
5 ;; Author: K. Shane Hartman
8 ;; This file is part of GNU Emacs.
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 2, or (at your option)
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.
20 ;; You should have received a copy of the GNU General Public License
21 ;; along with GNU Emacs; see the file COPYING. If not, write to
22 ;; the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
26 ;; This package provides the `view' major mode documented in the Emacs
31 (defvar view-mode-map nil
)
34 (setq view-mode-map
(make-keymap))
35 (fillarray (nth 1 view-mode-map
) 'View-undefined
)
36 (define-key view-mode-map
"\C-c" 'view-exit
)
37 (define-key view-mode-map
"\C-z" 'suspend-emacs
)
38 (define-key view-mode-map
"q" 'view-exit
)
39 (define-key view-mode-map
"-" 'negative-argument
)
40 (define-key view-mode-map
"0" 'digit-argument
)
41 (define-key view-mode-map
"1" 'digit-argument
)
42 (define-key view-mode-map
"2" 'digit-argument
)
43 (define-key view-mode-map
"3" 'digit-argument
)
44 (define-key view-mode-map
"4" 'digit-argument
)
45 (define-key view-mode-map
"5" 'digit-argument
)
46 (define-key view-mode-map
"6" 'digit-argument
)
47 (define-key view-mode-map
"7" 'digit-argument
)
48 (define-key view-mode-map
"8" 'digit-argument
)
49 (define-key view-mode-map
"9" 'digit-argument
)
50 (define-key view-mode-map
"\C-u" 'universal-argument
)
51 (define-key view-mode-map
"\e" nil
)
52 (define-key view-mode-map
"\C-x" 'Control-X-prefix
)
53 (define-key view-mode-map
"\e-" 'negative-argument
)
54 (define-key view-mode-map
"\e0" 'digit-argument
)
55 (define-key view-mode-map
"\e1" 'digit-argument
)
56 (define-key view-mode-map
"\e2" 'digit-argument
)
57 (define-key view-mode-map
"\e3" 'digit-argument
)
58 (define-key view-mode-map
"\e4" 'digit-argument
)
59 (define-key view-mode-map
"\e5" 'digit-argument
)
60 (define-key view-mode-map
"\e6" 'digit-argument
)
61 (define-key view-mode-map
"\e7" 'digit-argument
)
62 (define-key view-mode-map
"\e8" 'digit-argument
)
63 (define-key view-mode-map
"\e9" 'digit-argument
)
64 (define-key view-mode-map
"<" 'beginning-of-buffer
)
65 (define-key view-mode-map
">" 'end-of-buffer
)
66 (define-key view-mode-map
"\ev" 'View-scroll-lines-backward
)
67 (define-key view-mode-map
"\C-v" 'View-scroll-lines-forward
)
68 (define-key view-mode-map
" " 'View-scroll-lines-forward
)
69 (define-key view-mode-map
"\177" 'View-scroll-lines-backward
)
70 (define-key view-mode-map
"\n" 'View-scroll-one-more-line
)
71 (define-key view-mode-map
"\r" 'View-scroll-one-more-line
)
72 (define-key view-mode-map
"\C-l" 'recenter
)
73 (define-key view-mode-map
"z" 'View-scroll-lines-forward-set-scroll-size
)
74 (define-key view-mode-map
"g" 'View-goto-line
)
75 (define-key view-mode-map
"=" 'what-line
)
76 (define-key view-mode-map
"." 'set-mark-command
)
77 (define-key view-mode-map
"\C-@" 'set-mark-command
)
78 (define-key view-mode-map
"'" 'View-back-to-mark
)
79 (define-key view-mode-map
"@" 'View-back-to-mark
)
80 (define-key view-mode-map
"x" 'exchange-point-and-mark
)
81 (define-key view-mode-map
"h" 'Helper-describe-bindings
)
82 (define-key view-mode-map
"?" 'Helper-describe-bindings
)
83 (define-key view-mode-map
(char-to-string help-char
) 'Helper-help
)
84 (define-key view-mode-map
"\C-n" 'next-line
)
85 (define-key view-mode-map
"\C-p" 'previous-line
)
86 (define-key view-mode-map
"\C-s" 'isearch-forward
)
87 (define-key view-mode-map
"\C-r" 'isearch-backward
)
88 (define-key view-mode-map
"s" 'isearch-forward
)
89 (define-key view-mode-map
"r" 'isearch-backward
)
90 (define-key view-mode-map
"/" 'View-search-regexp-forward
)
91 (define-key view-mode-map
"\\" 'View-search-regexp-backward
)
92 ;; This conflicts with the standard binding of isearch-regexp-forward
93 (define-key view-mode-map
"\e\C-s" 'View-search-regexp-forward
)
94 (define-key view-mode-map
"\e\C-r" 'View-search-regexp-backward
)
95 (define-key view-mode-map
"n" 'View-search-last-regexp-forward
)
96 (define-key view-mode-map
"p" 'View-search-last-regexp-backward
)
101 (defun view-file (file-name)
102 "View FILE in View mode, returning to previous buffer when done.
103 The usual Emacs commands are not available; instead,
104 a special set of commands (mostly letters and punctuation)
105 are defined for moving around in the buffer.
106 Space scrolls forward, Delete scrolls backward.
107 For list of all View commands, type ? or h while viewing.
109 This command runs the normal hook `view-mode-hook'."
110 (interactive "fView file: ")
111 (let ((old-buf (current-buffer))
112 (had-a-buf (get-file-buffer file-name
))
113 (buf-to-view (find-file-noselect file-name
)))
114 (switch-to-buffer buf-to-view t
)
116 (and (not had-a-buf
) (not (buffer-modified-p buf-to-view
))
120 (defun view-file-other-window (file-name)
121 "View FILE in View mode in other window.
122 Return to previous buffer when done.
123 The usual Emacs commands are not available; instead,
124 a special set of commands (mostly letters and punctuation)
125 are defined for moving around in the buffer.
126 Space scrolls forward, Delete scrolls backward.
127 For list of all View commands, type ? or h while viewing.
129 This command runs the normal hook `view-mode-hook'."
130 (interactive "fView file: ")
131 (let ((old-arrangement (current-window-configuration))
132 (had-a-buf (get-file-buffer file-name
))
133 (buf-to-view (find-file-noselect file-name
)))
134 (switch-to-buffer-other-window buf-to-view
)
135 (view-mode old-arrangement
136 (and (not had-a-buf
) (not (buffer-modified-p buf-to-view
))
140 (defun view-buffer (buffer-name)
141 "View BUFFER in View mode, returning to previous buffer when done.
142 The usual Emacs commands are not available; instead,
143 a special set of commands (mostly letters and punctuation)
144 are defined for moving around in the buffer.
145 Space scrolls forward, Delete scrolls backward.
146 For list of all View commands, type ? or h while viewing.
148 This command runs the normal hook `view-mode-hook'."
149 (interactive "bView buffer: ")
150 (let ((old-buf (current-buffer)))
151 (switch-to-buffer buffer-name t
)
152 (view-mode old-buf nil
)))
155 (defun view-buffer-other-window (buffer-name not-return
)
156 "View BUFFER in View mode in another window,
157 returning to original buffer when done *only* if
158 prefix argument NOT-RETURN is nil (which is the default).
160 The usual Emacs commands are not available in View mode; instead,
161 a special set of commands (mostly letters and punctuation)
162 are defined for moving around in the buffer.
163 Space scrolls forward, Delete scrolls backward.
164 For list of all View commands, type ? or h while viewing.
166 This command runs the normal hook `view-mode-hook'."
167 (interactive "bView buffer:\nP")
168 (let ((return-to (and not-return
(current-window-configuration))))
169 (switch-to-buffer-other-window buffer-name
)
170 (view-mode return-to
)))
173 (defun view-mode (&optional prev-buffer action
)
174 "Major mode for viewing text but not editing it.
175 Letters do not insert themselves. Instead these commands are provided.
176 Most commands take prefix arguments. Commands dealing with lines
177 default to \"scroll size\" lines (initially size of window).
178 Search commands default to a repeat count of one.
179 M-< or < move to beginning of buffer.
180 M-> or > move to end of buffer.
181 C-v or Space scroll forward lines.
182 M-v or DEL scroll backward lines.
183 CR or LF scroll forward one line (backward with prefix argument).
184 z like Space except set number of lines for further
185 scrolling commands to scroll by.
186 C-u and Digits provide prefix arguments. `-' denotes negative argument.
187 = prints the current line number.
188 g goes to line given by prefix argument.
189 / or M-C-s searches forward for regular expression
190 \\ or M-C-r searches backward for regular expression.
191 n searches forward for last regular expression.
192 p searches backward for last regular expression.
193 C-@ or . set the mark.
194 x exchanges point and mark.
195 C-s or s do forward incremental search.
196 C-r or r do reverse incremental search.
197 @ or ' return to mark and pops mark ring.
198 Mark ring is pushed at start of every
199 successful search and when jump to line to occurs.
200 The mark is set on jump to buffer start or end.
201 ? or h provide help message (list of commands).
202 \\[Helper-help] provides help (list of commands or description of a command).
203 C-n moves down lines vertically.
204 C-p moves upward lines vertically.
205 C-l recenters the screen.
206 q or C-c exit view-mode and return to previous buffer.
208 Entry to this mode runs the normal hook `view-mode-hook'.
211 ; Not interactive because dangerous things happen
212 ; if you call it without passing a buffer as argument
213 ; and they are not easy to fix.
215 (make-local-variable 'view-old-mode-line-buffer-identification
)
216 (setq view-old-mode-line-buffer-identification
217 mode-line-buffer-identification
)
218 (make-local-variable 'view-old-buffer-read-only
)
219 (setq view-old-buffer-read-only buffer-read-only
)
220 (make-local-variable 'view-old-mode-name
)
221 (setq view-old-mode-name mode-name
)
222 (make-local-variable 'view-old-major-mode
)
223 (setq view-old-major-mode major-mode
)
224 (make-local-variable 'view-old-local-map
)
225 (setq view-old-local-map
(current-local-map))
226 (make-local-variable 'view-old-Helper-return-blurb
)
227 (setq view-old-Helper-return-blurb
228 (and (boundp 'Helper-return-blurb
) Helper-return-blurb
))
230 (setq buffer-read-only t
)
231 (setq mode-line-buffer-identification
233 (if (buffer-file-name)
236 (setq mode-name
"View")
237 (setq major-mode
'view-mode
)
238 (setq Helper-return-blurb
239 (format "continue viewing %s"
240 (if (buffer-file-name)
241 (file-name-nondirectory (buffer-file-name))
244 (make-local-variable 'view-exit-action
)
245 (setq view-exit-action action
)
246 (make-local-variable 'view-return-here
)
247 (setq view-return-here prev-buffer
)
248 (make-local-variable 'view-exit-position
)
249 (setq view-exit-position
(point-marker))
251 (make-local-variable 'view-scroll-size
)
252 (setq view-scroll-size nil
)
253 (make-local-variable 'view-last-regexp
)
254 (setq view-last-regexp nil
)
257 (setq goal-column nil
)
259 (use-local-map view-mode-map
)
260 (run-hooks 'view-hook
'view-mode-hook
)
261 (view-helpful-message))
265 "Exit from view-mode.
266 If you viewed an existing buffer, that buffer returns to its previous mode.
267 If you viewed a file that was not present in Emacs, its buffer is killed."
269 (setq mode-line-buffer-identification
270 view-old-mode-line-buffer-identification
)
271 (setq major-mode view-old-major-mode
)
272 (setq mode-name view-old-mode-name
)
273 (use-local-map view-old-local-map
)
274 (setq buffer-read-only view-old-buffer-read-only
)
276 (goto-char view-exit-position
)
277 (set-marker view-exit-position nil
)
279 ;; Now do something to the buffer that we were viewing
280 ;; (such as kill it).
281 (let ((viewed-buffer (current-buffer))
282 (action view-exit-action
))
284 ((bufferp view-return-here
)
285 (switch-to-buffer view-return-here
))
286 ((window-configuration-p view-return-here
)
287 (set-window-configuration view-return-here
)))
288 (if action
(funcall action viewed-buffer
))))
290 (defun view-helpful-message ()
292 (substitute-command-keys
293 "Type \\[Helper-help] for help, \\[Helper-describe-bindings] for commands, \\[view-exit] to quit.")))
295 (defun View-undefined ()
298 (view-helpful-message))
300 (defun view-window-size () (1- (window-height)))
302 (defun view-scroll-size ()
303 (min (view-window-size) (or view-scroll-size
(view-window-size))))
305 (defvar view-hook nil
306 "Normal hook run when starting to view a buffer or file.")
308 (defvar view-mode-hook nil
309 "Normal hook run when starting to view a buffer or file.")
311 ;(defun view-last-command (&optional who what)
312 ; (setq view-last-command-entry this-command)
313 ; (setq view-last-command who)
314 ; (setq view-last-command-argument what))
316 ;(defun View-repeat-last-command ()
317 ; "Repeat last command issued in View mode."
319 ; (if (and view-last-command
320 ; (eq view-last-command-entry last-command))
321 ; (funcall view-last-command view-last-command-argument))
322 ; (setq this-command view-last-command-entry))
324 (defun View-goto-line (&optional line
)
325 "Move to line LINE in View mode.
326 Display is centered at LINE. Sets mark at starting position and pushes
330 (goto-line (or line
1))
331 (recenter (/ (view-window-size) 2)))
333 (defun View-scroll-lines-forward (&optional lines
)
334 "Scroll forward in View mode, or exit if end of text is visible.
335 No arg means whole window full, or number of lines set by \\[View-scroll-lines-forward-set-scroll-size].
336 Arg is number of lines to scroll."
338 (if (and (pos-visible-in-window-p (point-max))
339 ;; Allow scrolling backward at the end of the buffer.
344 (if lines
(prefix-numeric-value lines
)
346 ;; (view-last-command 'View-scroll-lines-forward lines)
347 (if (>= lines
(view-window-size))
349 (if (>= (- lines
) (view-window-size))
352 (cond ((pos-visible-in-window-p (point-max))
353 (goto-char (point-max))
355 (message (substitute-command-keys
356 "End. Type \\[view-exit] to quit viewing."))))
357 (move-to-window-line -
1)
358 (beginning-of-line)))
360 (defun View-scroll-lines-forward-set-scroll-size (&optional lines
)
361 "Scroll forward LINES lines in View mode, setting the \"scroll size\".
362 This is the number of lines which \\[View-scroll-lines-forward] and \\[View-scroll-lines-backward] scroll by default.
363 The absolute value of LINES is used, so this command can be used to scroll
364 backwards (but \"scroll size\" is always positive). If LINES is greater than
365 window height or omitted, then window height is assumed. If LINES is less
366 than window height then scrolling context is provided from previous screen."
369 (setq view-scroll-size
(view-window-size))
370 (setq lines
(prefix-numeric-value lines
))
371 (setq view-scroll-size
372 (min (if (> lines
0) lines
(- lines
)) (view-window-size))))
373 (View-scroll-lines-forward lines
))
375 (defun View-scroll-one-more-line (&optional arg
)
376 "Scroll one more line up in View mode.
377 With ARG scroll one line down."
379 (View-scroll-lines-forward (if (not arg
) 1 -
1)))
381 (defun View-scroll-lines-backward (&optional lines
)
382 "Scroll backward in View mode.
383 No arg means whole window full, or number of lines set by \\[View-scroll-lines-forward-set-scroll-size].
384 Arg is number of lines to scroll."
386 (View-scroll-lines-forward (if lines
387 (- (prefix-numeric-value lines
))
388 (- (view-scroll-size)))))
390 (defun View-search-regexp-forward (n regexp
)
391 "Search forward for Nth occurrence of REGEXP.
392 Displays line found at center of window. REGEXP is remembered for
393 searching with \\[View-search-last-regexp-forward] and \\[View-search-last-regexp-backward]. Sets mark at starting position and pushes mark ring."
394 (interactive "p\nsSearch forward (regexp): ")
395 (if (> (length regexp
) 0)
397 ;(view-last-command 'View-search-last-regexp-forward n)
398 (view-search n regexp
))))
400 (defun View-search-regexp-backward (n regexp
)
401 "Search backward from window start for Nth instance of REGEXP.
402 Displays line found at center of window. REGEXP is remembered for
403 searching with \\[View-search-last-regexp-forward] and \\[View-search-last-regexp-backward]. Sets mark at starting position and pushes mark ring."
404 (interactive "p\nsSearch backward (regexp): ")
405 (View-search-regexp-forward (- n
) regexp
))
407 (defun View-search-last-regexp-forward (n)
408 "Search forward from window end for Nth instance of last regexp.
409 Displays line found at center of window. Sets mark at starting position
410 and pushes mark ring."
412 (View-search-regexp-forward n view-last-regexp
))
414 (defun View-search-last-regexp-backward (n)
415 "Search backward from window start for Nth instance of last regexp.
416 Displays line found at center of window. Sets mark at starting position and
419 (View-search-regexp-backward n view-last-regexp
))
421 (defun View-back-to-mark (&optional ignore
)
422 "Return to last mark set in View mode, else beginning of file.
423 Displays line at center of window. Pops mark ring so successive
424 invocations return to earlier marks."
426 (goto-char (or (mark) (point-min)))
428 (recenter (/ (view-window-size) 2)))
430 (defun view-search (times regexp
)
431 (setq view-last-regexp regexp
)
434 (move-to-window-line (if (< times
0) 0 -
1))
435 (if (re-search-forward regexp nil t times
)
436 (setq where
(point))))
442 (recenter (/ (view-window-size) 2)))
443 (message "Can't find occurrence %d of %s" times regexp
)
449 ;;; view.el ends here