1;;; view.el --- peruse file or buffer without editing 2 3;; Copyright (C) 1985, 1989, 1994, 1995, 1997, 2000, 2001, 2002, 4;; 2003, 2004, 2005, 2006, 2007 Free Software Foundation, Inc. 5 6;; Author: K. Shane Hartman 7;; Maintainer: Inge Frick <inge@nada.kth.se> 8;; Keywords: files 9 10;; This file is part of GNU Emacs. 11 12;; GNU Emacs is free software; you can redistribute it and/or modify 13;; it under the terms of the GNU General Public License as published by 14;; the Free Software Foundation; either version 2, or (at your option) 15;; any later version. 16 17;; GNU Emacs is distributed in the hope that it will be useful, 18;; but WITHOUT ANY WARRANTY; without even the implied warranty of 19;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 20;; GNU General Public License for more details. 21 22;; You should have received a copy of the GNU General Public License 23;; along with GNU Emacs; see the file COPYING. If not, write to the 24;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, 25;; Boston, MA 02110-1301, USA. 26 27;;; Commentary: 28 29;; This package provides the `view' minor mode documented in the Emacs 30;; user's manual. 31;; View mode entry and exit is done through the functions view-mode-enter 32;; and view-mode-exit. Use these functions to enter or exit view-mode from 33;; emacs lisp programs. 34;; We use both view- and View- as prefix for symbols. View- is used as 35;; prefix for commands that have a key binding. view- is used for commands 36;; without key binding. The purpose of this is to make it easier for a 37;; user to use command name completion. 38 39;;; Suggested key bindings: 40;; 41;; (define-key ctl-x-4-map "v" 'view-file-other-window) ; ^x4v 42;; (define-key ctl-x-5-map "v" 'view-file-other-frame) ; ^x5v 43;; 44;; You could also bind view-file, view-buffer, view-buffer-other-window and 45;; view-buffer-other-frame to keys. 46 47;;; Code: 48 49(defgroup view nil 50 "Peruse file or buffer without editing." 51 :link '(function-link view-mode) 52 :link '(custom-manual "(emacs)Misc File Ops") 53 :group 'wp 54 :group 'editing) 55 56(defcustom view-highlight-face 'highlight 57 "*The face used for highlighting the match found by View mode search." 58 :type 'face 59 :group 'view) 60 61;; `view-mode-auto-exit' is replaced by the following option variable which 62;; only says if scrolling past buffer end should leave view mode or not, it 63;; doesn't say if leaving view mode should restore windows or not. The latter 64;; is now controlled by the presence of a value in `view-return-to-alist'. 65(defcustom view-scroll-auto-exit nil 66 "*Non-nil means scrolling past the end of buffer exits View mode. 67A value of nil means attempting to scroll past the end of the buffer, 68only rings the bell and gives a message on how to leave." 69 :type 'boolean 70 :group 'view) 71 72(defcustom view-try-extend-at-buffer-end nil 73 "*Non-nil means try to load more of file when reaching end of buffer. 74This variable is mainly intended to be temporarily set to non-nil by 75the F command in view-mode, but you can set it to t if you want the action 76for all scroll commands in view mode." 77 :type 'boolean 78 :group 'view) 79 80(defcustom view-remove-frame-by-deleting nil 81 "*Determine how View mode removes a frame no longer needed. 82If nil, make an icon of the frame. If non-nil, delete the frame." 83 :type 'boolean 84 :group 'view) 85 86(defcustom view-exits-all-viewing-windows nil 87 "*Non-nil means restore all windows used to view buffer. 88Commands that restore windows when finished viewing a buffer, apply to all 89windows that display the buffer and have restore information in 90`view-return-to-alist'. 91If `view-exits-all-viewing-windows' is nil, only the selected window is 92considered for restoring." 93 :type 'boolean 94 :group 'view) 95 96(defcustom view-inhibit-help-message nil 97 "*Non-nil inhibits the help message shown upon entering View mode." 98 :type 'boolean 99 :group 'view 100 :version "22.1") 101 102;;;###autoload 103(defvar view-mode nil 104 "Non-nil if View mode is enabled. 105Don't change this variable directly, you must change it by one of the 106functions that enable or disable view mode.") 107;;;###autoload 108(make-variable-buffer-local 'view-mode) 109 110(defcustom view-mode-hook nil 111 "Normal hook run when starting to view a buffer or file." 112 :type 'hook 113 :group 'view) 114 115(defvar view-old-buffer-read-only nil) 116(make-variable-buffer-local 'view-old-buffer-read-only) 117 118(defvar view-old-Helper-return-blurb) 119(make-variable-buffer-local 'view-old-Helper-return-blurb) 120 121;; Just to avoid warnings. 122(defvar Helper-return-blurb) 123 124(defvar view-page-size nil 125 "Default number of lines to scroll by View page commands. 126If nil that means use the window size.") 127(make-variable-buffer-local 'view-page-size) 128 129(defvar view-half-page-size nil 130 "Default number of lines to scroll by View half page commands. 131If nil that means use half the window size.") 132(make-variable-buffer-local 'view-half-page-size) 133 134(defvar view-last-regexp nil) 135(make-variable-buffer-local 'view-last-regexp) ; Global is better??? 136 137(defvar view-return-to-alist nil 138 "What to do with used windows and where to go when finished viewing buffer. 139This is local in each buffer being viewed. 140It is added to by `view-mode-enter' when starting to view a buffer and 141subtracted from by `view-mode-exit' when finished viewing the buffer. 142 143See RETURN-TO-ALIST argument of function `view-mode-exit' for the format of 144`view-return-to-alist'.") 145(make-variable-buffer-local 'view-return-to-alist) 146(put 'view-return-to-alist 'permanent-local t) 147 148(defvar view-exit-action nil 149 "nil or a function with one argument (a buffer) called when finished viewing. 150This is local in each buffer being viewed. 151The \\[view-file] and \\[view-file-other-window] commands may set this to 152`kill-buffer'.") 153(make-variable-buffer-local 'view-exit-action) 154 155(defvar view-no-disable-on-exit nil 156 "If non-nil, View mode \"exit\" commands don't actually disable View mode. 157Instead, these commands just switch buffers or windows. 158This is set in certain buffers by specialized features such as help commands 159that use View mode automatically.") 160 161(defvar view-overlay nil 162 "Overlay used to display where a search operation found its match. 163This is local in each buffer, once it is used.") 164(make-variable-buffer-local 'view-overlay) 165 166(unless (assq 'view-mode minor-mode-alist) 167 (setq minor-mode-alist 168 (cons (list 'view-mode 169 (propertize " View" 170 'local-map mode-line-minor-mode-keymap 171 'help-echo "mouse-3: minor mode menu")) 172 minor-mode-alist))) 173 174;; Define keymap inside defvar to make it easier to load changes. 175;; Some redundant "less"-like key bindings below have been commented out. 176(defvar view-mode-map 177 (let ((map (make-sparse-keymap))) 178 (define-key map "C" 'View-kill-and-leave) 179 (define-key map "c" 'View-leave) 180 (define-key map "Q" 'View-quit-all) 181 (define-key map "E" 'View-exit-and-edit) 182; (define-key map "v" 'View-exit) 183 (define-key map "e" 'View-exit) 184 (define-key map "q" 'View-quit) 185; (define-key map "N" 'View-search-last-regexp-backward) 186 (define-key map "p" 'View-search-last-regexp-backward) 187 (define-key map "n" 'View-search-last-regexp-forward) 188; (define-key map "?" 'View-search-regexp-backward) ; Less does this. 189 (define-key map "\\" 'View-search-regexp-backward) 190 (define-key map "/" 'View-search-regexp-forward) 191 (define-key map "r" 'isearch-backward) 192 (define-key map "s" 'isearch-forward) 193 (define-key map "m" 'point-to-register) 194 (define-key map "'" 'register-to-point) 195 (define-key map "x" 'exchange-point-and-mark) 196 (define-key map "@" 'View-back-to-mark) 197 (define-key map "." 'set-mark-command) 198 (define-key map "%" 'View-goto-percent) 199; (define-key map "G" 'View-goto-line-last) 200 (define-key map "g" 'View-goto-line) 201 (define-key map "=" 'what-line) 202 (define-key map "F" 'View-revert-buffer-scroll-page-forward) 203; (define-key map "k" 'View-scroll-line-backward) 204 (define-key map "y" 'View-scroll-line-backward) 205; (define-key map "j" 'View-scroll-line-forward) 206 (define-key map "\n" 'View-scroll-line-forward) 207 (define-key map "\r" 'View-scroll-line-forward) 208 (define-key map "u" 'View-scroll-half-page-backward) 209 (define-key map "d" 'View-scroll-half-page-forward) 210 (define-key map "z" 'View-scroll-page-forward-set-page-size) 211 (define-key map "w" 'View-scroll-page-backward-set-page-size) 212; (define-key map "b" 'View-scroll-page-backward) 213 (define-key map "\C-?" 'View-scroll-page-backward) 214; (define-key map "f" 'View-scroll-page-forward) 215 (define-key map " " 'View-scroll-page-forward) 216 (define-key map "o" 'View-scroll-to-buffer-end) 217 (define-key map ">" 'end-of-buffer) 218 (define-key map "<" 'beginning-of-buffer) 219 (define-key map "-" 'negative-argument) 220 (define-key map "9" 'digit-argument) 221 (define-key map "8" 'digit-argument) 222 (define-key map "7" 'digit-argument) 223 (define-key map "6" 'digit-argument) 224 (define-key map "5" 'digit-argument) 225 (define-key map "4" 'digit-argument) 226 (define-key map "3" 'digit-argument) 227 (define-key map "2" 'digit-argument) 228 (define-key map "1" 'digit-argument) 229 (define-key map "0" 'digit-argument) 230 (define-key map "H" 'describe-mode) 231 (define-key map "?" 'describe-mode) ; Maybe do as less instead? See above. 232 (define-key map "h" 'describe-mode) 233 map)) 234 235(or (assq 'view-mode minor-mode-map-alist) 236 (setq minor-mode-map-alist 237 (cons (cons 'view-mode view-mode-map) minor-mode-map-alist))) 238 239;;; Commands that enter or exit view mode. 240 241;;;###autoload 242(defun view-file (file) 243 "View FILE in View mode, returning to previous buffer when done. 244Emacs commands editing the buffer contents are not available; instead, 245a special set of commands (mostly letters and punctuation) 246are defined for moving around in the buffer. 247Space scrolls forward, Delete scrolls backward. 248For list of all View commands, type H or h while viewing. 249 250This command runs the normal hook `view-mode-hook'." 251 (interactive "fView file: ") 252 (unless (file-exists-p file) (error "%s does not exist" file)) 253 (let ((had-a-buf (get-file-buffer file)) 254 (buffer (find-file-noselect file))) 255 (if (eq (with-current-buffer buffer 256 (get major-mode 'mode-class)) 257 'special) 258 (progn 259 (switch-to-buffer buffer) 260 (message "Not using View mode because the major mode is special")) 261 (view-buffer buffer (and (not had-a-buf) 'kill-buffer))))) 262 263;;;###autoload 264(defun view-file-other-window (file) 265 "View FILE in View mode in another window. 266Return that window to its previous buffer when done. 267Emacs commands editing the buffer contents are not available; instead, 268a special set of commands (mostly letters and punctuation) 269are defined for moving around in the buffer. 270Space scrolls forward, Delete scrolls backward. 271For list of all View commands, type H or h while viewing. 272 273This command runs the normal hook `view-mode-hook'." 274 (interactive "fIn other window view file: ") 275 (unless (file-exists-p file) (error "%s does not exist" file)) 276 (let ((had-a-buf (get-file-buffer file))) 277 (view-buffer-other-window (find-file-noselect file) nil 278 (and (not had-a-buf) 'kill-buffer)))) 279 280;;;###autoload 281(defun view-file-other-frame (file) 282 "View FILE in View mode in another frame. 283Maybe delete other frame and/or return to previous buffer when done. 284Emacs commands editing the buffer contents are not available; instead, 285a special set of commands (mostly letters and punctuation) 286are defined for moving around in the buffer. 287Space scrolls forward, Delete scrolls backward. 288For list of all View commands, type H or h while viewing. 289 290This command runs the normal hook `view-mode-hook'." 291 (interactive "fIn other frame view file: ") 292 (unless (file-exists-p file) (error "%s does not exist" file)) 293 (let ((had-a-buf (get-file-buffer file))) 294 (view-buffer-other-frame (find-file-noselect file) nil 295 (and (not had-a-buf) 'kill-buffer)))) 296 297 298;;;###autoload 299(defun view-buffer (buffer &optional exit-action) 300 "View BUFFER in View mode, returning to previous buffer when done. 301Emacs commands editing the buffer contents are not available; instead, 302a special set of commands (mostly letters and punctuation) 303are defined for moving around in the buffer. 304Space scrolls forward, Delete scrolls backward. 305For list of all View commands, type H or h while viewing. 306 307This command runs the normal hook `view-mode-hook'. 308 309Optional argument EXIT-ACTION is either nil or a function with buffer as 310argument. This function is called when finished viewing buffer. 311Use this argument instead of explicitly setting `view-exit-action'." 312 313 (interactive "bView buffer: ") 314 (let ((undo-window (list (window-buffer) (window-start) (window-point)))) 315 (switch-to-buffer buffer) 316 (view-mode-enter (cons (selected-window) (cons nil undo-window)) 317 exit-action))) 318 319;;;###autoload 320(defun view-buffer-other-window (buffer &optional not-return exit-action) 321 "View BUFFER in View mode in another window. 322Return to previous buffer when done, unless optional NOT-RETURN is non-nil. 323Emacs commands editing the buffer contents are not available; instead, 324a special set of commands (mostly letters and punctuation) 325are defined for moving around in the buffer. 326Space scrolls forward, Delete scrolls backward. 327For list of all View commands, type H or h while viewing. 328 329This command runs the normal hook `view-mode-hook'. 330 331Optional argument EXIT-ACTION is either nil or a function with buffer as 332argument. This function is called when finished viewing buffer. 333Use this argument instead of explicitly setting `view-exit-action'." 334 (interactive "bIn other window view buffer:\nP") 335 (let* ((win ; This window will be selected by 336 (get-lru-window)) ; switch-to-buffer-other-window below. 337 (return-to 338 (and (not not-return) 339 (cons (selected-window) 340 (if (eq win (selected-window)) 341 t ; Has to make new window. 342 (list 343 (window-buffer win) ; Other windows old buffer. 344 (window-start win) 345 (window-point win))))))) 346 (switch-to-buffer-other-window buffer) 347 (view-mode-enter (and return-to (cons (selected-window) return-to)) 348 exit-action))) 349 350;;;###autoload 351(defun view-buffer-other-frame (buffer &optional not-return exit-action) 352 "View BUFFER in View mode in another frame. 353Return to previous buffer when done, unless optional NOT-RETURN is non-nil. 354Emacs commands editing the buffer contents are not available; instead, 355a special set of commands (mostly letters and punctuation) 356are defined for moving around in the buffer. 357Space scrolls forward, Delete scrolls backward. 358For list of all View commands, type H or h while viewing. 359 360This command runs the normal hook `view-mode-hook'. 361 362Optional argument EXIT-ACTION is either nil or a function with buffer as 363argument. This function is called when finished viewing buffer. 364Use this argument instead of explicitly setting `view-exit-action'." 365 (interactive "bView buffer in other frame: \nP") 366 (let ((return-to 367 (and (not not-return) (cons (selected-window) t)))) ; Old window. 368 (switch-to-buffer-other-frame buffer) 369 (view-mode-enter (and return-to (cons (selected-window) return-to)) 370 exit-action))) 371 372;;;###autoload 373(defun view-mode (&optional arg) 374 ;; In the following documentation string we have to use some explicit key 375 ;; bindings instead of using the \\[] construction. The reason for this 376 ;; is that most commands have more than one key binding. 377 "Toggle View mode, a minor mode for viewing text but not editing it. 378With ARG, turn View mode on iff ARG is positive. 379 380Emacs commands that do not change the buffer contents are available as usual. 381Kill commands insert text in kill buffers but do not delete. Other commands 382\(among them most letters and punctuation) beep and tell that the buffer is 383read-only. 384\\<view-mode-map> 385The following additional commands are provided. Most commands take prefix 386arguments. Page commands default to \"page size\" lines which is almost a whole 387window full, or number of lines set by \\[View-scroll-page-forward-set-page-size] or \\[View-scroll-page-backward-set-page-size]. Half page commands default to 388and set \"half page size\" lines which initially is half a window full. Search 389commands default to a repeat count of one. 390 391H, h, ? This message. 392Digits provide prefix arguments. 393\\[negative-argument] negative prefix argument. 394\\[beginning-of-buffer] move to the beginning of buffer. 395> move to the end of buffer. 396\\[View-scroll-to-buffer-end] scroll so that buffer end is at last line of window. 397SPC scroll forward \"page size\" lines. 398 With prefix scroll forward prefix lines. 399DEL scroll backward \"page size\" lines. 400 With prefix scroll backward prefix lines. 401\\[View-scroll-page-forward-set-page-size] like \\[View-scroll-page-forward] but with prefix sets \"page size\" to prefix. 402\\[View-scroll-page-backward-set-page-size] like \\[View-scroll-page-backward] but with prefix sets \"page size\" to prefix. 403\\[View-scroll-half-page-forward] scroll forward \"half page size\" lines. With prefix, sets 404 \"half page size\" to prefix lines and scrolls forward that much. 405\\[View-scroll-half-page-backward] scroll backward \"half page size\" lines. With prefix, sets 406 \"half page size\" to prefix lines and scrolls backward that much. 407RET, LFD scroll forward one line. With prefix scroll forward prefix line(s). 408y scroll backward one line. With prefix scroll backward prefix line(s). 409\\[View-revert-buffer-scroll-page-forward] revert-buffer if necessary and scroll forward. 410 Use this to view a changing file. 411\\[what-line] prints the current line number. 412\\[View-goto-percent] goes prefix argument (default 100) percent into buffer. 413\\[View-goto-line] goes to line given by prefix argument (default first line). 414. set the mark. 415x exchanges point and mark. 416\\[View-back-to-mark] return to mark and pops mark ring. 417 Mark ring is pushed at start of every successful search and when 418 jump to line occurs. The mark is set on jump to buffer start or end. 419\\[point-to-register] save current position in character register. 420' go to position saved in character register. 421s do forward incremental search. 422r do reverse incremental search. 423\\[View-search-regexp-forward] searches forward for regular expression, starting after current page. 424 ! and @ have a special meaning at the beginning of the regexp. 425 ! means search for a line with no match for regexp. @ means start 426 search at beginning (end for backward search) of buffer. 427\\ searches backward for regular expression, starting before current page. 428\\[View-search-last-regexp-forward] searches forward for last regular expression. 429p searches backward for last regular expression. 430\\[View-quit] quit View mode, restoring this window and buffer to previous state. 431 \\[View-quit] is the normal way to leave view mode. 432\\[View-exit] exit View mode but stay in current buffer. Use this if you started 433 viewing a buffer (file) and find out you want to edit it. 434 This command restores the previous read-only status of the buffer. 435\\[View-exit-and-edit] exit View mode, and make the current buffer editable 436 even if it was not editable before entry to View mode. 437\\[View-quit-all] quit View mode, restoring all windows to previous state. 438\\[View-leave] quit View mode and maybe switch buffers, but don't kill this buffer. 439\\[View-kill-and-leave] quit View mode, kill current buffer and go back to other buffer. 440 441The effect of \\[View-leave], \\[View-quit] and \\[View-kill-and-leave] depends on how view-mode was entered. If it was 442entered by view-file, view-file-other-window, view-file-other-frame, or 443\\[dired-view-file] \(\\[view-file], \\[view-file-other-window], 444\\[view-file-other-frame], or the Dired mode v command), 445then \\[View-quit] will try to kill the current buffer. 446If view-mode was entered from another buffer, by \\[view-buffer], 447\\[view-buffer-other-window], \\[view-buffer-other frame], \\[view-file], 448\\[view-file-other-window], or \\[view-file-other-frame], 449then \\[View-leave], \\[View-quit] and \\[View-kill-and-leave] will return to that buffer. 450 451Entry to view-mode runs the normal hook `view-mode-hook'." 452 (interactive "P") 453 (unless (and arg ; Do nothing if already OK. 454 (if (> (prefix-numeric-value arg) 0) view-mode (not view-mode))) 455 (if view-mode (view-mode-disable) 456 (view-mode-enable)))) 457 458(defun view-mode-enable () 459 "Turn on View mode." 460 ;; Always leave view mode before changing major mode. 461 ;; This is to guarantee that the buffer-read-only variable is restored. 462 (add-hook 'change-major-mode-hook 'view-mode-disable nil t) 463 (setq view-mode t 464 view-page-size nil 465 view-half-page-size nil 466 view-old-buffer-read-only buffer-read-only 467 buffer-read-only t 468 view-old-Helper-return-blurb (and (boundp 'Helper-return-blurb) 469 Helper-return-blurb) 470 Helper-return-blurb 471 (format "continue viewing %s" 472 (if (buffer-file-name) 473 (file-name-nondirectory (buffer-file-name)) 474 (buffer-name)))) 475 (force-mode-line-update) 476 (run-hooks 'view-mode-hook)) 477 478(defun view-mode-disable () 479 "Turn off View mode." 480 (remove-hook 'change-major-mode-hook 'view-mode-disable t) 481 (and view-overlay (delete-overlay view-overlay)) 482 (force-mode-line-update) 483 ;; Calling toggle-read-only while View mode is enabled 484 ;; sets view-read-only to t as a buffer-local variable 485 ;; after exiting View mode. That arranges that the next toggle-read-only 486 ;; will reenable View mode. 487 ;; Cancelling View mode in any other way should cancel that, too, 488 ;; so that View mode stays off if toggle-read-only is called. 489 (if (local-variable-p 'view-read-only) 490 (kill-local-variable 'view-read-only)) 491 (setq view-mode nil 492 Helper-return-blurb view-old-Helper-return-blurb) 493 (if buffer-read-only 494 (setq buffer-read-only view-old-buffer-read-only))) 495 496;;;###autoload 497(defun view-mode-enter (&optional return-to exit-action) "\ 498Enter View mode and set up exit from view mode depending on optional arguments. 499If RETURN-TO is non-nil it is added as an element to the buffer local alist 500`view-return-to-alist'. 501Save EXIT-ACTION in buffer local variable `view-exit-action'. 502It should be either nil or a function that takes a buffer as argument. 503This function will be called by `view-mode-exit'. 504 505RETURN-TO is either nil, meaning do nothing when exiting view mode, or 506it has the format (WINDOW OLD-WINDOW . OLD-BUF-INFO). 507WINDOW is a window used for viewing. 508OLD-WINDOW is nil or the window to select after viewing. 509OLD-BUF-INFO tells what to do with WINDOW when exiting. It is one of: 5101) nil Do nothing. 5112) t Delete WINDOW or, if it is the only window, its frame. 5123) (OLD-BUFF START POINT) Display buffer OLD-BUFF with displayed text 513 starting at START and point at POINT in WINDOW. 5144) quit-window Do `quit-window' in WINDOW. 515 516For list of all View commands, type H or h while viewing. 517 518This function runs the normal hook `view-mode-hook'." 519 (if return-to 520 (let ((entry (assq (car return-to) view-return-to-alist))) 521 (if entry (setcdr entry (cdr return-to)) 522 (setq view-return-to-alist (cons return-to view-return-to-alist))))) 523 (if exit-action (setq view-exit-action exit-action)) 524 (unless view-mode ; Do nothing if already in view mode. 525 (view-mode-enable) 526 (force-mode-line-update) 527 (unless view-inhibit-help-message 528 (message "%s" 529 (substitute-command-keys "\ 530View mode: type \\[help-command] for help, \\[describe-mode] for commands, \\[View-quit] to quit."))))) 531 532(defun view-mode-exit (&optional return-to-alist exit-action all-win) 533 "Exit View mode in various ways, depending on optional arguments. 534RETURN-TO-ALIST, EXIT-ACTION and ALL-WIN determine what to do after exit. 535EXIT-ACTION is nil or a function that is called with current buffer as 536argument. 537RETURN-TO-ALIST is an alist that for some of the windows displaying the 538current buffer, associate information on what to do with those windows. 539If ALL-WIN or the variable `view-exits-all-viewing-windows' is non-nil, 540then all windows on RETURN-TO-ALIST are restored to their old state. 541Otherwise only the selected window is affected (if it is on RETURN-TO-ALIST). 542 543Elements of RETURN-TO-ALIST have the format (WINDOW OLD-WINDOW . OLD-BUF-INFO). 544WINDOW is a window displaying the current buffer. 545OLD-WINDOW is nil or a window to select after viewing. 546OLD-BUF-INFO is information on what to do with WINDOW and is one of: 5471) nil Do nothing. 5482) t Delete WINDOW and, if it is the only window, its frame. 5493) (OLD-BUF START POINT) Display buffer OLD-BUF with displayed text 550 starting at START and point at POINT in WINDOW. 5514) quit-window Do `quit-window' in WINDOW. 552 553If one of the WINDOW in RETURN-TO-ALIST is the selected window and the 554corresponding OLD-WINDOW is a live window, then select OLD-WINDOW." 555 (setq all-win 556 (and return-to-alist (or all-win view-exits-all-viewing-windows))) 557 (if view-mode ; Only do something if in view mode. 558 (let* ((buffer (current-buffer)) 559 window notlost 560 (sel-old (assq (selected-window) return-to-alist)) 561 (alist (cond 562 (all-win ; Try to restore all windows. 563 (append return-to-alist nil)) ; Copy. 564 (sel-old ; Only selected window. 565 (list sel-old)))) 566 (old-window (if sel-old (car (cdr sel-old))))) 567 (if all-win ; Follow chains of old-windows. 568 (let ((c (length alist)) a) 569 (while (and (> c 0) ; Safety if mutually refering windows. 570 (or (not (window-live-p old-window)) 571 (eq buffer (window-buffer old-window))) 572 (setq a (assq old-window alist))) 573 (setq c (1- c)) 574 (setq old-window (car (cdr a)))) 575 (if (or (zerop c) (not (window-live-p old-window))) 576 (setq old-window (selected-window))))) 577 (or view-no-disable-on-exit 578 (view-mode-disable)) 579 (while alist ; Restore windows with info. 580 (setq notlost nil) 581 (if (and (window-live-p (setq window (car (car alist)))) 582 (eq buffer (window-buffer window))) 583 (let ((frame (window-frame window)) 584 (old-buf-info (cdr (cdr (car alist))))) 585 (if all-win (select-window window)) 586 (cond 587 ((and (consp old-buf-info) ; Case 3. 588 (buffer-live-p (car old-buf-info))) 589 (set-window-buffer window (car old-buf-info)) ; old-buf 590 (set-window-start window (car (cdr old-buf-info))) 591 (set-window-point window (car (cdr (cdr old-buf-info))))) 592 ((eq old-buf-info 'quit-window) 593 (quit-window)) ; Case 4. 594 ((not (eq old-buf-info t)) nil) ; Not case 2, do nothing. 595 ((not (one-window-p t)) (delete-window)) 596 ((not (eq frame (next-frame))) 597 ;; Not the only frame, so can safely be removed. 598 (if view-remove-frame-by-deleting 599 (delete-frame frame) 600 (setq notlost t) ; Keep the window. See below. 601 (iconify-frame frame)))))) 602 ;; If a frame is removed by iconifying it, then the window is not 603 ;; really lost. In this case we keep the entry in 604 ;; view-return-to-alist so that if the user deiconifies the frame 605 ;; and then press q, then the frame is iconified again. 606 (unless notlost 607 (setq view-return-to-alist 608 (delete (car alist) view-return-to-alist))) 609 (setq alist (cdr alist))) 610 (if (window-live-p old-window) ; still existing window 611 (select-window old-window)) 612 (when exit-action 613 (setq view-exit-action nil) 614 (funcall exit-action buffer)) 615 (force-mode-line-update)))) 616 617(defun View-exit () 618 "Exit View mode but stay in current buffer." 619 (interactive) 620 (view-mode-exit)) 621 622;;;###autoload 623(defun View-exit-and-edit () 624 "Exit View mode and make the current buffer editable." 625 (interactive) 626 (let ((view-old-buffer-read-only nil) 627 (view-no-disable-on-exit nil)) 628 (view-mode-exit))) 629 630(defun View-leave () 631 "Quit View mode and maybe switch buffers, but don't kill this buffer." 632 (interactive) 633 (view-mode-exit view-return-to-alist)) 634 635(defun View-quit () 636 "Quit View mode, trying to restore window and buffer to previous state. 637Maybe kill this buffer. Try to restore selected window to previous state 638and go to previous buffer or window." 639 (interactive) 640 (view-mode-exit view-return-to-alist view-exit-action)) 641 642(defun View-quit-all () 643 "Quit View mode, trying to restore windows and buffers to previous state. 644Maybe kill current buffer. Try to restore all windows viewing buffer to 645previous state and go to previous buffer or window." 646 (interactive) 647 (view-mode-exit view-return-to-alist view-exit-action t)) 648 649(defun View-kill-and-leave () 650 "Quit View mode, kill current buffer and return to previous buffer." 651 (interactive) 652 (view-mode-exit view-return-to-alist (or view-exit-action 'kill-buffer) t)) 653 654 655;;; Some help routines. 656 657(defun view-window-size () 658 ;; Window height excluding mode line. 659 (1- (window-height))) 660 661;(defun view-last-command (&optional who what) 662; (setq view-last-command-entry this-command) 663; (setq view-last-command who) 664; (setq view-last-command-argument what)) 665 666;(defun View-repeat-last-command () 667; "Repeat last command issued in View mode." 668; (interactive) 669; (if (and view-last-command 670; (eq view-last-command-entry last-command)) 671; (funcall view-last-command view-last-command-argument)) 672; (setq this-command view-last-command-entry)) 673 674(defun view-recenter () 675 ;; Center point in window. 676 (recenter (/ (view-window-size) 2))) 677 678(defun view-page-size-default (lines) 679 ;; Get page size. 680 (let ((default (- (view-window-size) next-screen-context-lines))) 681 (if (or (null lines) (zerop (setq lines (prefix-numeric-value lines)))) 682 default 683 (min (abs lines) default)))) 684 685(defun view-set-half-page-size-default (lines) 686 ;; Get and maybe set half page size. 687 (if (not lines) (or view-half-page-size 688 (/ (view-window-size) 2)) 689 (setq view-half-page-size 690 (if (zerop (setq lines (prefix-numeric-value lines))) 691 (/ (view-window-size) 2) 692 (view-page-size-default lines))))) 693 694 695;;; Commands for moving around in the buffer. 696 697(defun View-goto-percent (&optional percent) 698 "Move to end (or prefix PERCENT) of buffer in View mode. 699Display is centered at point. 700Also set the mark at the position where point was." 701 (interactive "P") 702 (push-mark) 703 (goto-char 704 (if percent 705 (+ (point-min) 706 (floor (* (- (point-max) (point-min)) 0.01 707 (max 0 (min 100 (prefix-numeric-value percent)))))) 708 (point-max))) 709 (view-recenter)) 710 711;(defun View-goto-line-last (&optional line) 712;"Move to last (or prefix LINE) line in View mode. 713;Display is centered at LINE. 714;Sets mark at starting position and pushes mark ring." 715; (interactive "P") 716; (push-mark) 717; (if line (goto-line (prefix-numeric-value line)) 718; (goto-char (point-max)) 719; (beginning-of-line)) 720; (view-recenter)) 721 722(defun View-goto-line (&optional line) 723 "Move to first (or prefix LINE) line in View mode. 724Display is centered at LINE. 725Also set the mark at the position where point was." 726 (interactive "p") 727 (push-mark) 728 (goto-line line) 729 (view-recenter)) 730 731(defun View-back-to-mark (&optional ignore) 732 "Return to last mark set in View mode, else beginning of file. 733Display that line at the center of the window. 734This command pops the mark ring, so that successive 735invocations return to earlier marks." 736 (interactive) 737 (goto-char (or (mark t) (point-min))) 738 (pop-mark) 739 (view-recenter)) 740 741(defun view-scroll-lines (lines backward default maxdefault) 742 ;; This function does the job for all the scrolling commands. 743 ;; Scroll forward LINES lines. If BACKWARD is true scroll backwards. 744 ;; If LINES is negative scroll in the other direction. If LINES is 0 or nil, 745 ;; scroll DEFAULT lines. If MAXDEFAULT is true then scroll no more than a 746 ;; window full. 747 (if (or (null lines) (zerop (setq lines (prefix-numeric-value lines)))) 748 (setq lines default)) 749 (when (< lines 0) 750 (setq backward (not backward)) (setq lines (- lines))) 751 (setq default (view-page-size-default nil)) ; Max scrolled at a time. 752 (if maxdefault (setq lines (min lines default))) 753 (cond 754 (backward (scroll-down lines)) 755 ((view-really-at-end) 756 (if view-scroll-auto-exit (View-quit) 757 (ding) 758 (view-end-message))) 759 (t (while (> lines default) 760 (scroll-up default) 761 (setq lines (- lines default)) 762 (if (view-really-at-end) (setq lines 0))) 763 (scroll-up lines) 764 (if (view-really-at-end) (view-end-message)) 765 (move-to-window-line -1) 766 (beginning-of-line)))) 767 768(defun view-really-at-end () 769 ;; Return true if buffer end visible. Maybe revert buffer and test. 770 (and (pos-visible-in-window-p (point-max)) 771 (let ((buf (current-buffer)) 772 (bufname (buffer-name)) 773 (file (buffer-file-name))) 774 (or (not view-try-extend-at-buffer-end) 775 (null file) 776 (verify-visited-file-modtime buf) 777 (not (file-exists-p file)) 778 (when (buffer-modified-p buf) 779 (setq file (file-name-nondirectory file)) 780 (not (yes-or-no-p 781 (format 782 "File %s changed on disk. Discard your edits%s? " 783 file 784 (if (string= bufname file) "" 785 (concat " in " bufname)))))) 786 (progn 787 (revert-buffer t t t) 788 (pos-visible-in-window-p (point-max))))))) 789 790(defun view-end-message () 791 ;; Tell that we are at end of buffer. 792 (goto-char (point-max)) 793 (if view-return-to-alist 794 (message "End of buffer. Type %s to quit viewing." 795 (substitute-command-keys 796 (if view-scroll-auto-exit "\\[View-scroll-page-forward]" 797 "\\[View-quit]"))) 798 (message "End of buffer"))) 799 800(defun View-scroll-to-buffer-end () 801 "Scroll backward or forward so that buffer end is at last line of window." 802 (interactive) 803 (let ((p (if (pos-visible-in-window-p (point-max)) (point)))) 804 (goto-char (point-max)) 805 (recenter -1) 806 (and p (goto-char p)))) 807 808(defun View-scroll-page-forward (&optional lines) 809 "Scroll \"page size\" or prefix LINES lines forward in View mode. 810Exit if end of text is visible and `view-scroll-auto-exit' is non-nil. 811\"page size\" is whole window full, or number of lines set by 812\\[View-scroll-page-forward-set-page-size] or 813\\[View-scroll-page-backward-set-page-size]. 814If LINES is more than a window-full, only the last window-full is shown." 815 (interactive "P") 816 (view-scroll-lines lines nil (view-page-size-default view-page-size) nil)) 817 818(defun View-scroll-page-backward (&optional lines) 819 "Scroll \"page size\" or prefix LINES lines backward in View mode. 820See also `View-scroll-page-forward'." 821 (interactive "P") 822 (view-scroll-lines lines t (view-page-size-default view-page-size) nil)) 823 824(defun View-scroll-page-forward-set-page-size (&optional lines) 825 "Scroll forward LINES lines in View mode, setting the \"page size\". 826This is the number of lines which \\[View-scroll-page-forward] and 827\\[View-scroll-page-backward] scroll by default. 828If LINES is omitted or = 0, sets \"page size\" to window height and 829scrolls forward that much, otherwise scrolls forward LINES lines and sets 830\"page size\" to the minimum of window height and the absolute value of LINES. 831See also `View-scroll-page-forward'." 832 (interactive "P") 833 (view-scroll-lines lines nil 834 (setq view-page-size (view-page-size-default lines)) 835 nil)) 836 837(defun View-scroll-page-backward-set-page-size (&optional lines) 838 "Scroll backward prefix LINES lines in View mode, setting the \"page size\". 839See also `View-scroll-page-forward-set-page-size'." 840 (interactive "P") 841 (view-scroll-lines lines t 842 (setq view-page-size (view-page-size-default lines)) 843 nil)) 844 845(defun View-scroll-line-forward (&optional lines) 846 "Scroll forward one line (or prefix LINES lines) in View mode. 847See also `View-scroll-page-forward,' but note that scrolling is limited 848to minimum of LINES and one window-full." 849 (interactive "P") 850 (view-scroll-lines lines nil 1 t)) 851 852(defun View-scroll-line-backward (&optional lines) 853 "Scroll backward one line (or prefix LINES lines) in View mode. 854See also `View-scroll-line-forward'." 855 (interactive "P") 856 (view-scroll-lines lines t 1 t)) 857 858(defun View-scroll-half-page-forward (&optional lines) 859 "Scroll forward a \"half page\" (or prefix LINES) lines in View mode. 860If LINES is not omitted, the \"half page size\" is set to the minimum of 861window height and the absolute value of LINES. 862LINES=0 resets \"half page size\" to half window height." 863 (interactive "P") 864 (view-scroll-lines lines nil (view-set-half-page-size-default lines) t)) 865 866(defun View-scroll-half-page-backward (&optional lines) 867 "Scroll backward a \"half page\" (or prefix LINES) lines in View mode. 868See also `View-scroll-half-page-forward'." 869 (interactive "P") 870 (view-scroll-lines lines t (view-set-half-page-size-default lines) t)) 871 872(defun View-revert-buffer-scroll-page-forward (&optional lines) 873 "Scroll forward, reverting buffer if needed, in View mode. 874If buffer has not been changed and the corresponding file is newer, first 875revert the buffer, then scroll. 876This command is useful if you are viewing a changing file. 877 878The prefix argument LINES says how many lines to scroll. 879If you don't specify a prefix argument, it uses the number of lines set by 880\\[View-scroll-page-forward-set-page-size] or 881\\[View-scroll-page-backward-set-page-size]. 882If LINES is more than a window-full, only the last window-full is shown." 883 (interactive "P") 884 (let ((view-scroll-auto-exit nil) 885 (view-try-extend-at-buffer-end t)) 886 (view-scroll-lines lines nil (view-page-size-default view-page-size) nil))) 887 888(defun View-search-regexp-forward (n regexp) 889 "Search forward for first (or prefix Nth) occurrence of REGEXP in View mode. 890 891Displays line found at center of window. Sets mark at starting position and 892pushes mark ring. 893 894Characters @ and ! are special at the beginning of REGEXP. They modify 895the search rather than become part of the pattern searched for. 896@ means search all the buffer i.e. start search at the beginning of buffer. 897! means search for a line that contains no match for the pattern. 898If REGEXP is empty or only consist of these control characters, then 899an earlier remembered REGEXP is used, otherwise REGEXP is remembered 900for use by later search commands. 901 902The variable `view-highlight-face' controls the face that is used 903for highlighting the match that is found." 904 (interactive "p\nsSearch forward (regexp): ") 905 (view-search n regexp)) 906 907(defun View-search-regexp-backward (n regexp) 908 "Search backward for first (or prefix Nth) occurrence of REGEXP in View mode. 909 910Displays line found at center of window. Sets mark at starting position and 911pushes mark ring. 912 913Characters @ and ! are special at the beginning of REGEXP. They modify 914the search rather than become part of the pattern searched for. 915@ means search all the buffer i.e. start search at the end of buffer. 916! means search for a line that contains no match for the pattern. 917If REGEXP is empty or only consist of these control characters, then 918an earlier remembered REGEXP is used, otherwise REGEXP is remembered 919for use by later search commands. 920 921The variable `view-highlight-face' controls the face that is used 922for highlighting the match that is found." 923 (interactive "p\nsSearch backward (regexp): ") 924 (view-search (- n) regexp)) 925 926(defun View-search-last-regexp-forward (n) "\ 927Search forward for first (or prefix Nth) instance of last regexp in View mode. 928Displays line found at center of window. Sets mark at starting position and 929pushes mark ring. 930 931The variable `view-highlight-face' controls the face that is used 932for highlighting the match that is found." 933 (interactive "p") 934 (view-search n nil)) 935 936(defun View-search-last-regexp-backward (n) "\ 937Search backward for first (or prefix Nth) instance of last regexp in View mode. 938Displays line found at center of window. Sets mark at starting position and 939pushes mark ring. 940 941The variable `view-highlight-face' controls the face that is used 942for highlighting the match that is found." 943 (interactive "p") 944 (view-search (- n) nil)) 945 946(defun view-search (times regexp) 947 ;; This function does the job for all the View-search- commands. 948 ;; Search for the TIMESt match for REGEXP. If TIMES is negative 949 ;; search backwards. If REGEXP is nil use `view-last-regexp'. 950 ;; Charcters "!" and "@" have a special meaning at the beginning of 951 ;; REGEXP and are removed from REGEXP before the search "!" means 952 ;; search for lines with no match for REGEXP. "@" means search in 953 ;; the whole buffer, don't start searching from the present point. 954 (let (where no end ln) 955 (cond 956 ((and regexp (> (length regexp) 0) 957 (or (not (memq (string-to-char regexp) '(?! ?@))) 958 (progn 959 (if (member (substring regexp 0 2) '("!@" "@!")) 960 (setq end t no t ln 2) 961 (setq no (not (setq end (eq ?@ (string-to-char regexp)))) 962 ln 1)) 963 (> (length (setq regexp (substring regexp ln))) 0)))) 964 (setq view-last-regexp (if no (list regexp) regexp))) 965 ((consp view-last-regexp) 966 (setq regexp (car view-last-regexp)) 967 (unless (setq no (not no)) (setq view-last-regexp regexp))) 968 (view-last-regexp (setq regexp view-last-regexp) 969 (if no (setq view-last-regexp (list regexp)))) 970 (t (error "No previous View-mode search"))) 971 (save-excursion 972 (if end (goto-char (if (< times 0) (point-max) (point-min))) 973 (move-to-window-line (if (< times 0) 0 -1))) 974 (if (if no (view-search-no-match-lines times regexp) 975 (re-search-forward regexp nil t times)) 976 (setq where (point)))) 977 (if where 978 (progn 979 (push-mark) 980 (goto-char where) 981 (if view-overlay 982 (move-overlay view-overlay (match-beginning 0) (match-end 0)) 983 (setq view-overlay 984 (make-overlay (match-beginning 0) (match-end 0)))) 985 (overlay-put view-overlay 'face view-highlight-face) 986 (beginning-of-line) 987 (view-recenter)) 988 (message "Can't find occurrence %d of %s%s" 989 times (if no "no " "") regexp) 990 (sit-for 4)))) 991 992(defun view-search-no-match-lines (times regexp) 993 ;; Search for the TIMESt occurrence of line with no match for REGEXP. 994 (let ((back (and (< times 0) (setq times (- times)) -1)) 995 n) 996 (while (> times 0) 997 (save-excursion (beginning-of-line (if back (- times) (1+ times))) 998 (setq n (point))) 999 (setq times 1000 (cond 1001 ((< (count-lines (point) n) times) -1) ; Not enough lines. 1002 ((or (null (re-search-forward regexp nil t back)) 1003 (if back (and (< (match-end 0) n) 1004 (> (count-lines (match-end 0) n) 1)) 1005 (and (< n (match-beginning 0)) 1006 (> (count-lines n (match-beginning 0)) 1)))) 1007 0) ; No match within lines. 1008 (back (count-lines (max n (match-beginning 0)) (match-end 0))) 1009 (t (count-lines (match-beginning 0) (min n (match-end 0)))))) 1010 (goto-char n)) 1011 (and (zerop times) (looking-at "^.*$")))) 1012 1013 1014(provide 'view) 1015 1016;;; arch-tag: 6d0ace36-1d12-4de3-8de3-1fa3231636d7 1017;;; view.el ends here 1018