| 1 | ;;; winner.el --- Restore old window configurations |
| 2 | |
| 3 | ;; Copyright (C) 1997-1998, 2001-2011 Free Software Foundation. Inc. |
| 4 | |
| 5 | ;; Author: Ivar Rummelhoff <ivarru@math.uio.no> |
| 6 | ;; Created: 27 Feb 1997 |
| 7 | ;; Keywords: convenience frames |
| 8 | |
| 9 | ;; This file is part of GNU Emacs. |
| 10 | |
| 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 3 of the License, or |
| 14 | ;; (at your option) any later version. |
| 15 | |
| 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. |
| 20 | |
| 21 | ;; You should have received a copy of the GNU General Public License |
| 22 | ;; along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>. |
| 23 | |
| 24 | ;;; Commentary: |
| 25 | |
| 26 | ;; Winner mode is a global minor mode that records the changes in the |
| 27 | ;; window configuration (i.e. how the frames are partitioned into |
| 28 | ;; windows) so that the changes can be "undone" using the command |
| 29 | ;; `winner-undo'. By default this one is bound to the key sequence |
| 30 | ;; ctrl-c left. If you change your mind (while undoing), you can |
| 31 | ;; press ctrl-c right (calling `winner-redo'). Even though it uses |
| 32 | ;; some features of Emacs20.3, winner.el should also work with |
| 33 | ;; Emacs19.34 and XEmacs20, provided that the installed version of |
| 34 | ;; custom is not obsolete. |
| 35 | |
| 36 | ;; Winner mode was improved August 1998. |
| 37 | ;; Further improvements February 2002. |
| 38 | |
| 39 | ;;; Code: |
| 40 | |
| 41 | (eval-when-compile |
| 42 | (require 'cl)) |
| 43 | |
| 44 | |
| 45 | (defmacro winner-active-region () |
| 46 | (if (boundp 'mark-active) |
| 47 | 'mark-active |
| 48 | '(region-active-p))) |
| 49 | |
| 50 | (defsetf winner-active-region () (store) |
| 51 | (if (featurep 'xemacs) |
| 52 | `(if ,store (zmacs-activate-region) |
| 53 | (zmacs-deactivate-region)) |
| 54 | `(setq mark-active ,store))) |
| 55 | |
| 56 | (defalias 'winner-edges |
| 57 | (if (featurep 'xemacs) 'window-pixel-edges 'window-edges)) |
| 58 | (defalias 'winner-window-list |
| 59 | (if (featurep 'xemacs) |
| 60 | (lambda () (delq (minibuffer-window) (window-list nil 0))) |
| 61 | (lambda () (window-list nil 0)))) |
| 62 | |
| 63 | (require 'ring) |
| 64 | |
| 65 | (defgroup winner nil |
| 66 | "Restoring window configurations." |
| 67 | :group 'windows) |
| 68 | |
| 69 | ;;;###autoload |
| 70 | (defcustom winner-mode nil |
| 71 | "Toggle Winner mode. |
| 72 | Setting this variable directly does not take effect; |
| 73 | use either \\[customize] or the function `winner-mode'." |
| 74 | :set #'(lambda (symbol value) (funcall symbol (or value 0))) |
| 75 | :initialize 'custom-initialize-default |
| 76 | :type 'boolean |
| 77 | :group 'winner |
| 78 | :require 'winner) |
| 79 | |
| 80 | (defcustom winner-dont-bind-my-keys nil |
| 81 | "If non-nil: Do not use `winner-mode-map' in Winner mode." |
| 82 | :type 'boolean |
| 83 | :group 'winner) |
| 84 | |
| 85 | (defcustom winner-ring-size 200 |
| 86 | "Maximum number of stored window configurations per frame." |
| 87 | :type 'integer |
| 88 | :group 'winner) |
| 89 | |
| 90 | (defcustom winner-boring-buffers '("*Completions*") |
| 91 | "`winner-undo' will not restore windows displaying any of these buffers. |
| 92 | You may want to include buffer names such as *Help*, *Apropos*, |
| 93 | *Buffer List*, *info* and *Compile-Log*." |
| 94 | :type '(repeat string) |
| 95 | :group 'winner) |
| 96 | |
| 97 | |
| 98 | |
| 99 | |
| 100 | \f |
| 101 | ;;;; Saving old configurations (internal variables and subroutines) |
| 102 | |
| 103 | |
| 104 | ;;; Current configuration |
| 105 | |
| 106 | ;; List the windows according to their edges. |
| 107 | (defun winner-sorted-window-list () |
| 108 | (sort (winner-window-list) |
| 109 | (lambda (x y) |
| 110 | (loop for a in (winner-edges x) |
| 111 | for b in (winner-edges y) |
| 112 | while (= a b) |
| 113 | finally return (< a b))))) |
| 114 | |
| 115 | (defun winner-win-data () |
| 116 | ;; Essential properties of the windows in the selected frame. |
| 117 | (loop for win in (winner-sorted-window-list) |
| 118 | collect (cons (winner-edges win) (window-buffer win)))) |
| 119 | |
| 120 | ;; This variable is updated with the current window configuration |
| 121 | ;; every time it changes. |
| 122 | (defvar winner-currents nil) |
| 123 | |
| 124 | ;; The current configuration (+ the buffers involved). |
| 125 | (defsubst winner-conf () |
| 126 | (cons (current-window-configuration) |
| 127 | (winner-win-data))) |
| 128 | |
| 129 | |
| 130 | ;; Save current configuration. |
| 131 | ;; (Called below by `winner-save-old-configurations'). |
| 132 | (defun winner-remember () |
| 133 | (let ((entry (assq (selected-frame) winner-currents))) |
| 134 | (if entry (setcdr entry (winner-conf)) |
| 135 | (push (cons (selected-frame) (winner-conf)) |
| 136 | winner-currents)))) |
| 137 | |
| 138 | ;; Consult `winner-currents'. |
| 139 | (defun winner-configuration (&optional frame) |
| 140 | (or (cdr (assq (or frame (selected-frame)) winner-currents)) |
| 141 | (letf (((selected-frame) frame)) |
| 142 | (winner-conf)))) |
| 143 | |
| 144 | |
| 145 | |
| 146 | ;;; Saved configurations |
| 147 | |
| 148 | ;; This variable contains the window cofiguration rings. |
| 149 | ;; The key in this alist is the frame. |
| 150 | (defvar winner-ring-alist nil) |
| 151 | |
| 152 | ;; Find the right ring. If it does not exist, create one. |
| 153 | (defsubst winner-ring (frame) |
| 154 | (or (cdr (assq frame winner-ring-alist)) |
| 155 | (let ((ring (make-ring winner-ring-size))) |
| 156 | (ring-insert ring (winner-configuration frame)) |
| 157 | (push (cons frame ring) winner-ring-alist) |
| 158 | ring))) |
| 159 | |
| 160 | \f |
| 161 | ;; If the same command is called several times in a row, |
| 162 | ;; we only save one window configuration. |
| 163 | (defvar winner-last-command nil) |
| 164 | |
| 165 | ;; Frames affected by the previous command. |
| 166 | (defvar winner-last-frames nil) |
| 167 | |
| 168 | |
| 169 | (defsubst winner-equal (a b) |
| 170 | "Check whether two Winner configurations (as produced by |
| 171 | `winner-conf') are equal." |
| 172 | (equal (cdr a) (cdr b))) |
| 173 | |
| 174 | |
| 175 | ;; Save the current window configuration, if it has changed. |
| 176 | ;; If so return frame, otherwise return nil. |
| 177 | (defun winner-insert-if-new (frame) |
| 178 | (unless (or (memq frame winner-last-frames) |
| 179 | (eq this-command 'winner-redo)) |
| 180 | (let ((conf (winner-configuration frame)) |
| 181 | (ring (winner-ring frame))) |
| 182 | (when (and (not (ring-empty-p ring)) |
| 183 | (winner-equal conf (ring-ref ring 0))) |
| 184 | ;; When the previous configuration was very similar, |
| 185 | ;; keep only the latest. |
| 186 | (ring-remove ring 0)) |
| 187 | (ring-insert ring conf) |
| 188 | (push frame winner-last-frames) |
| 189 | frame))) |
| 190 | |
| 191 | |
| 192 | |
| 193 | ;;; Hooks |
| 194 | |
| 195 | ;; Frames affected by the current command. |
| 196 | (defvar winner-modified-list nil) |
| 197 | |
| 198 | ;; Called whenever the window configuration changes |
| 199 | ;; (a `window-configuration-change-hook'). |
| 200 | (defun winner-change-fun () |
| 201 | (unless (or (memq (selected-frame) winner-modified-list) |
| 202 | (/= 0 (minibuffer-depth))) |
| 203 | (push (selected-frame) winner-modified-list))) |
| 204 | |
| 205 | ;; A `post-command-hook' for emacsen with |
| 206 | ;; `window-configuration-change-hook'. |
| 207 | (defun winner-save-old-configurations () |
| 208 | (when (zerop (minibuffer-depth)) |
| 209 | (unless (eq this-command winner-last-command) |
| 210 | (setq winner-last-frames nil) |
| 211 | (setq winner-last-command this-command)) |
| 212 | (dolist (frame winner-modified-list) |
| 213 | (winner-insert-if-new frame)) |
| 214 | (setq winner-modified-list nil) |
| 215 | (winner-remember))) |
| 216 | |
| 217 | ;; A `minibuffer-setup-hook'. |
| 218 | (defun winner-save-unconditionally () |
| 219 | (unless (eq this-command winner-last-command) |
| 220 | (setq winner-last-frames nil) |
| 221 | (setq winner-last-command this-command)) |
| 222 | (winner-insert-if-new (selected-frame)) |
| 223 | (winner-remember)) |
| 224 | |
| 225 | ;; A `post-command-hook' for other emacsen. |
| 226 | ;; Also called by `winner-undo' before "undoing". |
| 227 | (defun winner-save-conditionally () |
| 228 | (when (zerop (minibuffer-depth)) |
| 229 | (winner-save-unconditionally))) |
| 230 | |
| 231 | |
| 232 | |
| 233 | \f |
| 234 | ;;;; Restoring configurations |
| 235 | |
| 236 | ;; Works almost as `set-window-configuration', |
| 237 | ;; but does not change the contents or the size of the minibuffer, |
| 238 | ;; and tries to preserve the selected window. |
| 239 | (defun winner-set-conf (winconf) |
| 240 | (let* ((miniwin (minibuffer-window)) |
| 241 | (chosen (selected-window)) |
| 242 | (minisize (window-height miniwin))) |
| 243 | (letf (((window-buffer miniwin)) |
| 244 | ((window-point miniwin))) |
| 245 | (set-window-configuration winconf)) |
| 246 | (cond |
| 247 | ((window-live-p chosen) (select-window chosen)) |
| 248 | ((window-minibuffer-p (selected-window)) |
| 249 | (other-window 1))) |
| 250 | (when (/= minisize (window-height miniwin)) |
| 251 | (letf (((selected-window) miniwin) ) |
| 252 | (setf (window-height) minisize))))) |
| 253 | |
| 254 | |
| 255 | |
| 256 | (defvar winner-point-alist nil) |
| 257 | ;; `set-window-configuration' restores old points and marks. This is |
| 258 | ;; not what we want, so we make a list of the "real" (i.e. new) points |
| 259 | ;; and marks before undoing window configurations. |
| 260 | ;; |
| 261 | ;; Format of entries: (buffer (mark . mark-active) (window . point) ..) |
| 262 | |
| 263 | (defun winner-make-point-alist () |
| 264 | (letf (((current-buffer))) |
| 265 | (loop with alist |
| 266 | for win in (winner-window-list) |
| 267 | for entry = |
| 268 | (or (assq (window-buffer win) alist) |
| 269 | (car (push (list (set-buffer (window-buffer win)) |
| 270 | (cons (mark t) (winner-active-region))) |
| 271 | alist))) |
| 272 | do (push (cons win (window-point win)) |
| 273 | (cddr entry)) |
| 274 | finally return alist))) |
| 275 | |
| 276 | (defun winner-get-point (buf win) |
| 277 | ;; Consult (and possibly extend) `winner-point-alist'. |
| 278 | ;; Returns nil if buf no longer exists. |
| 279 | (when (buffer-name buf) |
| 280 | (let ((entry (assq buf winner-point-alist))) |
| 281 | (cond |
| 282 | (entry |
| 283 | (or (cdr (assq win (cddr entry))) |
| 284 | (cdr (assq nil (cddr entry))) |
| 285 | (letf (((current-buffer) buf)) |
| 286 | (push (cons nil (point)) (cddr entry)) |
| 287 | (point)))) |
| 288 | (t (letf (((current-buffer) buf)) |
| 289 | (push (list buf |
| 290 | (cons (mark t) (winner-active-region)) |
| 291 | (cons nil (point))) |
| 292 | winner-point-alist) |
| 293 | (point))))))) |
| 294 | |
| 295 | \f |
| 296 | ;; Make sure point does not end up in the minibuffer and delete |
| 297 | ;; windows displaying dead or boring buffers |
| 298 | ;; (c.f. `winner-boring-buffers'). Return nil if all the windows |
| 299 | ;; should be deleted. Preserve correct points and marks. |
| 300 | (defun winner-set (conf) |
| 301 | ;; For the format of `conf', see `winner-conf'. |
| 302 | (let* ((buffers nil) |
| 303 | (alive |
| 304 | ;; Possibly update `winner-point-alist' |
| 305 | (loop for buf in (mapcar 'cdr (cdr conf)) |
| 306 | for pos = (winner-get-point buf nil) |
| 307 | if (and pos (not (memq buf buffers))) |
| 308 | do (push buf buffers) |
| 309 | collect pos))) |
| 310 | (winner-set-conf (car conf)) |
| 311 | (let (xwins) ; to be deleted |
| 312 | |
| 313 | ;; Restore points |
| 314 | (dolist (win (winner-sorted-window-list)) |
| 315 | (unless (and (pop alive) |
| 316 | (setf (window-point win) |
| 317 | (winner-get-point (window-buffer win) win)) |
| 318 | (not (member (buffer-name (window-buffer win)) |
| 319 | winner-boring-buffers))) |
| 320 | (push win xwins))) ; delete this window |
| 321 | |
| 322 | ;; Restore marks |
| 323 | (letf (((current-buffer))) |
| 324 | (loop for buf in buffers |
| 325 | for entry = (cadr (assq buf winner-point-alist)) |
| 326 | do (progn (set-buffer buf) |
| 327 | (set-mark (car entry)) |
| 328 | (setf (winner-active-region) (cdr entry))))) |
| 329 | ;; Delete windows, whose buffers are dead or boring. |
| 330 | ;; Return t if this is still a possible configuration. |
| 331 | (or (null xwins) |
| 332 | (progn |
| 333 | (mapc 'delete-window (cdr xwins)) ; delete all but one |
| 334 | (unless (one-window-p t) |
| 335 | (delete-window (car xwins)) |
| 336 | t)))))) |
| 337 | |
| 338 | |
| 339 | |
| 340 | ;;;; Winner mode (a minor mode) |
| 341 | |
| 342 | (defcustom winner-mode-hook nil |
| 343 | "Functions to run whenever Winner mode is turned on." |
| 344 | :type 'hook |
| 345 | :group 'winner) |
| 346 | |
| 347 | (defcustom winner-mode-leave-hook nil |
| 348 | "Functions to run whenever Winner mode is turned off." |
| 349 | :type 'hook |
| 350 | :group 'winner) |
| 351 | |
| 352 | (defvar winner-mode-map |
| 353 | (let ((map (make-sparse-keymap))) |
| 354 | (define-key map [(control c) left] 'winner-undo) |
| 355 | (define-key map [(control c) right] 'winner-redo) |
| 356 | map) |
| 357 | "Keymap for Winner mode.") |
| 358 | |
| 359 | ;; Check if `window-configuration-change-hook' is working. |
| 360 | (defun winner-hook-installed-p () |
| 361 | (save-window-excursion |
| 362 | (let ((winner-var nil) |
| 363 | (window-configuration-change-hook |
| 364 | '((lambda () (setq winner-var t))))) |
| 365 | (split-window) |
| 366 | winner-var))) |
| 367 | |
| 368 | \f |
| 369 | ;;;###autoload |
| 370 | (defun winner-mode (&optional arg) |
| 371 | "Toggle Winner mode. |
| 372 | With arg, turn Winner mode on if and only if arg is positive." |
| 373 | (interactive "P") |
| 374 | (let ((on-p (if arg (> (prefix-numeric-value arg) 0) |
| 375 | (not winner-mode)))) |
| 376 | (cond |
| 377 | ;; Turn mode on |
| 378 | (on-p |
| 379 | (setq winner-mode t) |
| 380 | (cond |
| 381 | ((winner-hook-installed-p) |
| 382 | (add-hook 'window-configuration-change-hook 'winner-change-fun) |
| 383 | (add-hook 'post-command-hook 'winner-save-old-configurations)) |
| 384 | (t (add-hook 'post-command-hook 'winner-save-conditionally))) |
| 385 | (add-hook 'minibuffer-setup-hook 'winner-save-unconditionally) |
| 386 | (setq winner-modified-list (frame-list)) |
| 387 | (winner-save-old-configurations) |
| 388 | (run-hooks 'winner-mode-hook) |
| 389 | (when (called-interactively-p 'interactive) |
| 390 | (message "Winner mode enabled"))) |
| 391 | ;; Turn mode off |
| 392 | (winner-mode |
| 393 | (setq winner-mode nil) |
| 394 | (remove-hook 'window-configuration-change-hook 'winner-change-fun) |
| 395 | (remove-hook 'post-command-hook 'winner-save-old-configurations) |
| 396 | (remove-hook 'post-command-hook 'winner-save-conditionally) |
| 397 | (remove-hook 'minibuffer-setup-hook 'winner-save-unconditionally) |
| 398 | (run-hooks 'winner-mode-leave-hook) |
| 399 | (when (called-interactively-p 'interactive) |
| 400 | (message "Winner mode disabled")))))) |
| 401 | |
| 402 | ;; Inspired by undo (simple.el) |
| 403 | |
| 404 | (defvar winner-undo-frame nil) |
| 405 | |
| 406 | (defvar winner-pending-undo-ring nil |
| 407 | "The ring currently used by `winner-undo'.") |
| 408 | (defvar winner-undo-counter nil) |
| 409 | (defvar winner-undone-data nil) ; There confs have been passed. |
| 410 | |
| 411 | (defun winner-undo () |
| 412 | "Switch back to an earlier window configuration saved by Winner mode. |
| 413 | In other words, \"undo\" changes in window configuration." |
| 414 | (interactive) |
| 415 | (cond |
| 416 | ((not winner-mode) (error "Winner mode is turned off")) |
| 417 | (t (unless (and (eq last-command 'winner-undo) |
| 418 | (eq winner-undo-frame (selected-frame))) |
| 419 | (winner-save-conditionally) ; current configuration->stack |
| 420 | (setq winner-undo-frame (selected-frame)) |
| 421 | (setq winner-point-alist (winner-make-point-alist)) |
| 422 | (setq winner-pending-undo-ring (winner-ring (selected-frame))) |
| 423 | (setq winner-undo-counter 0) |
| 424 | (setq winner-undone-data (list (winner-win-data)))) |
| 425 | (incf winner-undo-counter) ; starting at 1 |
| 426 | (when (and (winner-undo-this) |
| 427 | (not (window-minibuffer-p (selected-window)))) |
| 428 | (message "Winner undo (%d / %d)" |
| 429 | winner-undo-counter |
| 430 | (1- (ring-length winner-pending-undo-ring))))))) |
| 431 | |
| 432 | |
| 433 | |
| 434 | \f |
| 435 | (defun winner-undo-this () ; The heart of winner undo. |
| 436 | (loop |
| 437 | (cond |
| 438 | ((>= winner-undo-counter (ring-length winner-pending-undo-ring)) |
| 439 | (message "No further window configuration undo information") |
| 440 | (return nil)) |
| 441 | |
| 442 | ((and ; If possible configuration |
| 443 | (winner-set (ring-ref winner-pending-undo-ring |
| 444 | winner-undo-counter)) |
| 445 | ; .. and new configuration |
| 446 | (let ((data (winner-win-data))) |
| 447 | (and (not (member data winner-undone-data)) |
| 448 | (push data winner-undone-data)))) |
| 449 | (return t)) ; .. then everything is fine. |
| 450 | (t ;; Otherwise, discharge it (and try the next one). |
| 451 | (ring-remove winner-pending-undo-ring winner-undo-counter))))) |
| 452 | |
| 453 | |
| 454 | (defun winner-redo () ; If you change your mind. |
| 455 | "Restore a more recent window configuration saved by Winner mode." |
| 456 | (interactive) |
| 457 | (cond |
| 458 | ((eq last-command 'winner-undo) |
| 459 | (winner-set |
| 460 | (if (zerop (minibuffer-depth)) |
| 461 | (ring-remove winner-pending-undo-ring 0) |
| 462 | (ring-ref winner-pending-undo-ring 0))) |
| 463 | (unless (eq (selected-window) (minibuffer-window)) |
| 464 | (message "Winner undid undo"))) |
| 465 | (t (error "Previous command was not a `winner-undo'")))) |
| 466 | |
| 467 | ;;; To be evaluated when the package is loaded: |
| 468 | |
| 469 | (unless (or (assq 'winner-mode minor-mode-map-alist) |
| 470 | winner-dont-bind-my-keys) |
| 471 | (push (cons 'winner-mode winner-mode-map) |
| 472 | minor-mode-map-alist)) |
| 473 | |
| 474 | (provide 'winner) |
| 475 | ;;; winner.el ends here |