lisp/desktop.el

   1 ;;; desktop.el --- save partial status of Emacs when killed
   2
   3 ;; Copyright (C) 1993, 1994, 1995, 1997, 2000, 2001
   4 ;;   Free Software Foundation, Inc.
   5
   6 ;; Author: Morten Welinder <terra@diku.dk>
   7 ;; Maintainter: Lars Hansen <larsh@math.ku.dk>
   8 ;; Keywords: convenience
   9 ;; Favourite-brand-of-beer: None, I hate beer.
  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 2, 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 the
  25 ;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  26 ;; Boston, MA 02111-1307, USA.
  27
  28 ;;; Commentary:
  29
  30 ;; Save the Desktop, i.e.,
  31 ;;      - some global variables
  32 ;;      - the list of buffers with associated files.  For each buffer also
  33 ;;              - the major mode
  34 ;;              - the default directory
  35 ;;              - the point
  36 ;;              - the mark & mark-active
  37 ;;              - buffer-read-only
  38 ;;              - some local variables
  39
  40 ;; To use this, first put these two lines in the bottom of your .emacs
  41 ;; file (the later the better):
  42 ;;
  43 ;;      (desktop-load-default)
  44 ;;      (desktop-read)
  45 ;;
  46 ;; Between these two lines you may wish to add something that updates the
  47 ;; variables `desktop-globals-to-save' and/or `desktop-locals-to-save'.  If
  48 ;; for instance you want to save the local variable `foobar' for every buffer
  49 ;; in which it is local, you could add the line
  50 ;;
  51 ;;      (setq desktop-locals-to-save (cons 'foobar desktop-locals-to-save))
  52 ;;
  53 ;; To avoid saving excessive amounts of data you may also wish to add
  54 ;; something like the following
  55 ;;
  56 ;;      (add-hook 'kill-emacs-hook
  57 ;;                '(lambda ()
  58 ;;                   (desktop-truncate search-ring 3)
  59 ;;                   (desktop-truncate regexp-search-ring 3)))
  60 ;;
  61 ;; which will make sure that no more than three search items are saved.  You
  62 ;; must place this line *after* the `(desktop-load-default)' line.  See also
  63 ;; the variable `desktop-save-hook'.
  64
  65 ;; Start Emacs in the root directory of your "project". The desktop saver
  66 ;; is inactive by default.  You activate it by M-x desktop-save RET.  When
  67 ;; you exit the next time the above data will be saved.  This ensures that
  68 ;; all the files you were editing will be reloaded the next time you start
  69 ;; Emacs from the same directory and that points will be set where you
  70 ;; left them.  If you save a desktop file in your home directory it will
  71 ;; act as a default desktop when you start Emacs from a directory that
  72 ;; doesn't have its own.  I never do this, but you may want to.
  73
  74 ;; Some words on minor modes: Most minor modes are controlled by
  75 ;; buffer-local variables, which have a standard save / restore
  76 ;; mechanism.  To handle all minor modes, we take the following
  77 ;; approach: (1) check whether the variable name from
  78 ;; `minor-mode-alist' is also a function; and (2) use translation
  79 ;; table `desktop-minor-mode-table' in the case where the two names
  80 ;; are not the same.
  81
  82 ;; By the way: don't use desktop.el to customize Emacs -- the file .emacs
  83 ;; in your home directory is used for that.  Saving global default values
  84 ;; for buffers is an example of misuse.
  85
  86 ;; PLEASE NOTE: The kill ring can be saved as specified by the variable
  87 ;; `desktop-globals-to-save' (by default it isn't).  This may result in saving
  88 ;; things you did not mean to keep.  Use M-x desktop-clear RET.
  89
  90 ;; Thanks to  hetrick@phys.uva.nl (Jim Hetrick)      for useful ideas.
  91 ;;            avk@rtsg.mot.com (Andrew V. Klein)     for a dired tip.
  92 ;;            chris@tecc.co.uk (Chris Boucher)       for a mark tip.
  93 ;;            f89-kam@nada.kth.se (Klas Mellbourn)   for a mh-e tip.
  94 ;;            kifer@sbkifer.cs.sunysb.edu (M. Kifer) for a bug hunt.
  95 ;;            treese@lcs.mit.edu (Win Treese)        for ange-ftp tips.
  96 ;;            pot@cnuce.cnr.it (Francesco Potorti`)  for misc. tips.
  97 ;; ---------------------------------------------------------------------------
  98 ;; TODO:
  99 ;;
 100 ;; Save window configuration.
 101 ;; Recognize more minor modes.
 102 ;; Save mark rings.
 103
 104 ;;; Code:
 105
 106 ;; Make the compilation more silent
 107 (eval-when-compile
 108   ;; We use functions from these modules
 109   ;; We can't (require 'mh-e) since that wants to load something.
 110   (mapcar 'require '(info dired reporter)))
 111
 112 (defvar desktop-file-version "206"
 113   "Verion number of desktop file format.
 114 Written into the desktop file and used at desktop read to provide
 115 backward compatibility.")
 116
 117 ;; ----------------------------------------------------------------------------
 118 ;; USER OPTIONS -- settings you might want to play with.
 119 ;; ----------------------------------------------------------------------------
 120
 121 (defgroup desktop nil
 122   "Save status of Emacs when you exit."
 123   :group 'frames)
 124
 125 (defcustom desktop-enable nil
 126   "*Non-nil enable Desktop to save the state of Emacs when you exit."
 127   :group 'desktop
 128   :type 'boolean
 129   :require 'desktop
 130   :initialize 'custom-initialize-default
 131   :version "20.3")
 132
 133 (defcustom desktop-save 'ask-if-new
 134   "*When the user changes desktop or quits emacs, should the desktop be saved?
 135 \(in the current desktop directory)
 136    t             -- always save.
 137    ask           -- always ask.
 138    ask-if-new    -- ask if no desktop file exists, otherwise just save.
 139    ask-if-exists -- ask if desktop file exists, otherwise don't save.
 140    if-exists     -- save if desktop file exists, otherwise don't save.
 141    nil           -- never save.
 142 The desktop is never saved when `desktop-enable' is nil."
 143   :type '(choice
 144     (const :tag "Always save" t)
 145     (const :tag "Always ask" ask)
 146     (const :tag "Ask if desktop file is new, else do save" ask-if-new)
 147     (const :tag "Ask if desktop file exists, else don't save" ask-if-exists)
 148     (const :tag "Save if desktop file exists, else don't" if-exists)
 149     (const :tag "Never save" nil))
 150   :group 'desktop)
 151
 152 (defcustom desktop-base-file-name
 153   (convert-standard-filename ".emacs.desktop")
 154   "File for Emacs desktop, not including the directory name."
 155   :type 'file
 156   :group 'desktop)
 157 (defvaralias 'desktop-basefilename 'desktop-base-file-name)
 158
 159 (defcustom desktop-path '("." "~")
 160   "List of directories to search for the desktop file.
 161 The base name of the file is specified in `desktop-base-file-name'."
 162   :type '(repeat directory)
 163   :group 'desktop)
 164
 165 (defcustom desktop-missing-file-warning nil
 166   "*If non-nil then desktop warns when a file no longer exists.
 167 Otherwise it simply ignores that file."
 168   :type 'boolean
 169   :group 'desktop)
 170
 171 (defcustom desktop-no-desktop-file-hook nil
 172   "Normal hook run after fail of `desktop-read' due to missing desktop file.
 173 May e.g. be used to show a dired buffer."
 174   :type 'hook
 175   :group 'desktop)
 176
 177 (defcustom desktop-after-read-hook nil
 178   "Normal hook run after a sucessful `desktop-read'.
 179 May e.g. be used to show a buffer list."
 180   :type 'hook
 181   :group 'desktop)
 182
 183 (defcustom desktop-save-hook nil
 184   "Hook run before desktop saves the state of Emacs.
 185 This is useful for truncating history lists, for example."
 186   :type 'hook
 187   :group 'desktop)
 188
 189 (defcustom desktop-globals-to-save '(
 190   desktop-missing-file-warning
 191   tags-file-name
 192   tags-table-list
 193   search-ring
 194   regexp-search-ring
 195   register-alist)
 196   "List of global variables to save when killing Emacs.
 197 An element may be variable name (a symbol)
 198 or a cons cell of the form  (VAR . MAX-SIZE),
 199 which means to truncate VAR's value to at most MAX-SIZE elements
 200 \(if the value is a list) before saving the value.
 201 Feature: Saving `kill-ring' implies saving `kill-ring-yank-pointer'."
 202   :type '(repeat (restricted-sexp :match-alternatives (symbolp consp)))
 203   :group 'desktop)
 204
 205 (defcustom desktop-globals-to-clear '(
 206   kill-ring
 207   kill-ring-yank-pointer
 208   search-ring
 209   search-ring-yank-pointer
 210   regexp-search-ring
 211   regexp-search-ring-yank-pointer)
 212   "List of global variables set to clear by `desktop-clear'.
 213 An element may be variable name (a symbol) or a cons cell of the form
 214 \(VAR . FORM). Symbols are set to nil and for cons cells VAR is set
 215 to the value obtained by evaluateing FORM."
 216   :type '(repeat (restricted-sexp :match-alternatives (symbolp consp)))
 217   :group 'desktop)
 218
 219 (defcustom desktop-clear-preserve-buffers-regexp
 220   "^\\*tramp/.+\\*$"
 221   "Regexp identifying buffers that `desktop-clear' should not delete."
 222   :type 'regexp
 223   :group 'desktop)
 224
 225 ;; Maintained for backward compatibility
 226 (defcustom desktop-clear-preserve-buffers
 227   '("*scratch*" "*Messages*")
 228   "*List of buffer names that `desktop-clear' should not delete."
 229   :type '(repeat string)
 230   :group 'desktop)
 231
 232 (defvar desktop-locals-to-save '(
 233   desktop-locals-to-save  ; Itself!  Think it over.
 234   truncate-lines
 235   case-fold-search
 236   case-replace
 237   fill-column
 238   overwrite-mode
 239   change-log-default-name
 240   line-number-mode)
 241   "List of local variables to save for each buffer.
 242 The variables are saved only when they really are local.")
 243 (make-variable-buffer-local 'desktop-locals-to-save)
 244
 245 ;; We skip .log files because they are normally temporary.
 246 ;;         (ftp) files because they require passwords and whatnot.
 247 ;;         TAGS files to save time (tags-file-name is saved instead).
 248 (defcustom desktop-buffers-not-to-save
 249   "\\(^nn\\.a[0-9]+\\|\\.log\\|(ftp)\\|^tags\\|^TAGS\\)$"
 250   "Regexp identifying buffers that are to be excluded from saving."
 251   :type 'regexp
 252   :group 'desktop)
 253
 254 ;; Skip ange-ftp files
 255 (defcustom desktop-files-not-to-save
 256   "^/[^/:]*:"
 257   "Regexp identifying files whose buffers are to be excluded from saving."
 258   :type 'regexp
 259   :group 'desktop)
 260
 261 (defcustom desktop-buffer-modes-to-save
 262   '(Info-mode rmail-mode)
 263   "If a buffer is of one of these major modes, save the buffer name.
 264 It is up to the functions in `desktop-buffer-handlers' to decide
 265 whether the buffer should be recreated or not, and how."
 266   :type '(repeat symbol)
 267   :group 'desktop)
 268
 269 (defcustom desktop-modes-not-to-save nil
 270   "List of major modes whose buffers should not be saved."
 271   :type '(repeat symbol)
 272   :group 'desktop)
 273
 274 (defcustom desktop-file-name-format 'absolute
 275   "*Format in which desktop file names should be saved.
 276 Possible values are:
 277    absolute -- Absolute file name.
 278    tilde    -- Relative to ~.
 279    local    -- Relative to directory of desktop file."
 280   :type '(choice (const absolute) (const tilde) (const local))
 281   :group 'desktop)
 282
 283 (defcustom desktop-buffer-misc-functions
 284   '(desktop-buffer-info-misc-data
 285     desktop-buffer-dired-misc-data)
 286   "*Functions used to determine auxiliary information for a buffer.
 287 These functions are called in order, with no arguments.  If a function
 288 returns non-nil, its value is saved along with the desktop buffer for
 289 which it was called; no further functions will be called.
 290
 291 File names should formatted using the call
 292 \"(desktop-file-name FILE-NAME dirname)\".
 293
 294 Later, when desktop.el restores the buffers it has saved, each of the
 295 `desktop-buffer-handlers' functions will have access to a buffer local
 296 variable, named `desktop-buffer-misc', whose value is what the
 297 \"misc\" function returned previously."
 298   :type '(repeat function)
 299   :group 'desktop)
 300
 301 (defcustom desktop-buffer-handlers
 302   '(desktop-buffer-dired
 303     desktop-buffer-rmail
 304     desktop-buffer-mh
 305     desktop-buffer-info
 306     desktop-buffer-file)
 307   "*List of functions to call in order to create a buffer.
 308 The functions are called without explicit parameters but can use the
 309 following variables:
 310
 311    desktop-file-version
 312    desktop-buffer-file-name
 313    desktop-buffer-name
 314    desktop-buffer-major-mode
 315    desktop-buffer-minor-modes
 316    desktop-buffer-point
 317    desktop-buffer-mark
 318    desktop-buffer-read-only
 319    desktop-buffer-misc
 320    desktop-buffer-locals
 321
 322 If one function returns non-nil, no further functions are called.
 323 If the function returns a buffer, then the saved mode settings
 324 and variable values for that buffer are copied into it."
 325   :type '(repeat function)
 326   :group 'desktop)
 327
 328 (put 'desktop-buffer-handlers 'risky-local-variable t)
 329
 330 (defcustom desktop-minor-mode-table
 331   '((auto-fill-function auto-fill-mode)
 332     (vc-mode nil))
 333   "Table mapping minor mode variables to minor mode functions.
 334 Each entry has the form (NAME RESTORE-FUNCTION).
 335 NAME is the name of the buffer-local variable indicating that the minor
 336 mode is active.  RESTORE-FUNCTION is the function to activate the minor mode.
 337 called.  RESTORE-FUNCTION nil means don't try to restore the minor mode.
 338 Only minor modes for which the name of the buffer-local variable
 339 and the name of the minor mode function are different have to added to
 340 this table."
 341   :type 'sexp
 342   :group 'desktop)
 343
 344 ;; ----------------------------------------------------------------------------
 345 (defvar desktop-dirname nil
 346   "The directory in which the current desktop file resides.")
 347
 348 (defconst desktop-header
 349 ";; --------------------------------------------------------------------------
 350 ;; Desktop File for Emacs
 351 ;; --------------------------------------------------------------------------
 352 " "*Header to place in Desktop file.")
 353
 354 (defvar desktop-delay-hook nil
 355   "Hooks run after all buffers are loaded; intended for internal use.")
 356
 357 ;; ----------------------------------------------------------------------------
 358 (defun desktop-truncate (l n)
 359   "Truncate LIST to at most N elements destructively."
 360   (let ((here (nthcdr (1- n) l)))
 361     (if (consp here)
 362         (setcdr here nil))))
 363
 364 ;; ----------------------------------------------------------------------------
 365 (defun desktop-clear ()
 366   "Empty the Desktop.
 367 This kills all buffers except for internal ones and those listed
 368 in `desktop-clear-preserve-buffers'.  Furthermore, it clears the
 369 variables listed in `desktop-globals-to-clear'."
 370   (interactive)
 371   (dolist (var desktop-globals-to-clear)
 372     (if (symbolp var)
 373       (eval `(setq-default ,var nil))
 374       (eval `(setq-default ,(car var) ,(cdr var)))))
 375   (let ((buffers (buffer-list)))
 376     (while buffers
 377       (let ((bufname (buffer-name (car buffers))))
 378          (or
 379            (null bufname)
 380            (string-match desktop-clear-preserve-buffers-regexp bufname)
 381            (member bufname desktop-clear-preserve-buffers)
 382            ;; Don't kill buffers made for internal purposes.
 383            (and (not (equal bufname "")) (eq (aref bufname 0) ?\ ))
 384            (kill-buffer (car buffers))))
 385       (setq buffers (cdr buffers))))
 386   (delete-other-windows))
 387
 388 ;; ----------------------------------------------------------------------------
 389 (add-hook 'kill-emacs-hook 'desktop-kill)
 390
 391 (defun desktop-kill ()
 392   "If `desktop-enable' is non-nil, do what `desktop-save' says to do.
 393 If the desktop should be saved and `desktop-dirname'
 394 is nil, ask the user where to save the desktop."
 395   (when
 396     (and
 397       desktop-enable
 398       (let ((exists (file-exists-p (expand-file-name desktop-base-file-name desktop-dirname))))
 399         (or
 400           (eq desktop-save 't)
 401           (and exists (memq desktop-save '(ask-if-new if-exists)))
 402           (and
 403             (or
 404               (memq desktop-save '(ask ask-if-new))
 405               (and exists (eq desktop-save 'ask-if-exists)))
 406             (y-or-n-p "Save desktop? ")))))
 407     (unless desktop-dirname
 408       (setq desktop-dirname
 409         (file-name-as-directory
 410           (expand-file-name
 411             (call-interactively
 412               (lambda (dir) (interactive "DDirectory for desktop file: ") dir))))))
 413     (condition-case err
 414       (desktop-save desktop-dirname)
 415       (file-error
 416         (unless (yes-or-no-p "Error while saving the desktop. Ignore? ")
 417           (signal (car err) (cdr err)))))))
 418
 419 ;; ----------------------------------------------------------------------------
 420 (defun desktop-list* (&rest args)
 421   (if (null (cdr args))
 422       (car args)
 423     (setq args (nreverse args))
 424     (let ((value (cons (nth 1 args) (car args))))
 425       (setq args (cdr (cdr args)))
 426       (while args
 427         (setq value (cons (car args) value))
 428         (setq args (cdr args)))
 429       value)))
 430
 431 ;; ----------------------------------------------------------------------------
 432 (defun desktop-internal-v2s (val)
 433   "Convert VALUE to a pair (QUOTE . TXT); (eval (read TXT)) gives VALUE.
 434 TXT is a string that when read and evaluated yields value.
 435 QUOTE may be `may' (value may be quoted),
 436 `must' (values must be quoted), or nil (value may not be quoted)."
 437   (cond
 438    ((or (numberp val) (null val) (eq t val))
 439     (cons 'may (prin1-to-string val)))
 440    ((stringp val)
 441     (let ((copy (copy-sequence val)))
 442       (set-text-properties 0 (length copy) nil copy)
 443       ;; Get rid of text properties because we cannot read them
 444       (cons 'may (prin1-to-string copy))))
 445    ((symbolp val)
 446     (cons 'must (prin1-to-string val)))
 447    ((vectorp val)
 448     (let* ((special nil)
 449            (pass1 (mapcar
 450                    (lambda (el)
 451                      (let ((res (desktop-internal-v2s el)))
 452                        (if (null (car res))
 453                            (setq special t))
 454                        res))
 455                    val)))
 456       (if special
 457           (cons nil (concat "(vector "
 458                             (mapconcat (lambda (el)
 459                                          (if (eq (car el) 'must)
 460                                              (concat "'" (cdr el))
 461                                            (cdr el)))
 462                                        pass1
 463                                        " ")
 464                             ")"))
 465         (cons 'may (concat "[" (mapconcat 'cdr pass1 " ") "]")))))
 466    ((consp val)
 467     (let ((p val)
 468           newlist
 469           use-list*
 470           anynil)
 471       (while (consp p)
 472         (let ((q.txt (desktop-internal-v2s (car p))))
 473           (or anynil (setq anynil (null (car q.txt))))
 474           (setq newlist (cons q.txt newlist)))
 475         (setq p (cdr p)))
 476       (if p
 477           (let ((last (desktop-internal-v2s p))
 478                 (el (car newlist)))
 479             (or anynil (setq anynil (null (car last))))
 480             (or anynil
 481                 (setq newlist (cons '(must . ".") newlist)))
 482             (setq use-list* t)
 483             (setq newlist (cons last newlist))))
 484       (setq newlist (nreverse newlist))
 485       (if anynil
 486           (cons nil
 487                 (concat (if use-list* "(desktop-list* "  "(list ")
 488                         (mapconcat (lambda (el)
 489                                      (if (eq (car el) 'must)
 490                                          (concat "'" (cdr el))
 491                                        (cdr el)))
 492                                    newlist
 493                                    " ")
 494                         ")"))
 495         (cons 'must
 496               (concat "(" (mapconcat 'cdr newlist " ") ")")))))
 497    ((subrp val)
 498     (cons nil (concat "(symbol-function '"
 499                       (substring (prin1-to-string val) 7 -1)
 500                       ")")))
 501    ((markerp val)
 502     (let ((pos (prin1-to-string (marker-position val)))
 503           (buf (prin1-to-string (buffer-name (marker-buffer val)))))
 504       (cons nil (concat "(let ((mk (make-marker)))"
 505                         " (add-hook 'desktop-delay-hook"
 506                         " (list 'lambda '() (list 'set-marker mk "
 507                         pos " (get-buffer " buf ")))) mk)"))))
 508    (t                                   ; save as text
 509     (cons 'may "\"Unprintable entity\""))))
 510
 511 ;; ----------------------------------------------------------------------------
 512 (defun desktop-value-to-string (val)
 513   "Convert VALUE to a string that when read evaluates to the same value.
 514 Not all types of values are supported."
 515   (let* ((print-escape-newlines t)
 516          (float-output-format nil)
 517          (quote.txt (desktop-internal-v2s val))
 518          (quote (car quote.txt))
 519          (txt (cdr quote.txt)))
 520     (if (eq quote 'must)
 521         (concat "'" txt)
 522       txt)))
 523
 524 ;; ----------------------------------------------------------------------------
 525 (defun desktop-outvar (varspec)
 526   "Output a setq statement for variable VAR to the desktop file.
 527 The argument VARSPEC may be the variable name VAR (a symbol),
 528 or a cons cell of the form  (VAR . MAX-SIZE),
 529 which means to truncate VAR's value to at most MAX-SIZE elements
 530 \(if the value is a list) before saving the value."
 531   (let (var size)
 532     (if (consp varspec)
 533         (setq var (car varspec) size (cdr varspec))
 534       (setq var varspec))
 535     (if (boundp var)
 536         (progn
 537           (if (and (integerp size)
 538                    (> size 0)
 539                    (listp (eval var)))
 540               (desktop-truncate (eval var) size))
 541           (insert "(setq "
 542                   (symbol-name var)
 543                   " "
 544                   (desktop-value-to-string (symbol-value var))
 545                   ")\n")))))
 546
 547 ;; ----------------------------------------------------------------------------
 548 (defun desktop-save-buffer-p (filename bufname mode &rest dummy)
 549   "Return t if the desktop should record a particular buffer for next startup.
 550 FILENAME is the visited file name, BUFNAME is the buffer name, and
 551 MODE is the major mode."
 552   (let ((case-fold-search nil))
 553     (and (not (string-match desktop-buffers-not-to-save bufname))
 554          (not (memq mode desktop-modes-not-to-save))
 555          (or (and filename
 556                   (not (string-match desktop-files-not-to-save filename)))
 557              (and (eq mode 'dired-mode)
 558                   (save-excursion
 559                     (set-buffer (get-buffer bufname))
 560                     (not (string-match desktop-files-not-to-save
 561                                        default-directory))))
 562              (and (null filename)
 563                   (memq mode desktop-buffer-modes-to-save))))))
 564
 565 ;; ----------------------------------------------------------------------------
 566 (defun desktop-file-name (filename dirname)
 567   "Convert FILENAME to format specified in `desktop-file-name-format'.
 568 DIRNAME must be the directory in which the desktop file will be saved."
 569   (cond
 570     ((not filename) nil)
 571     ((eq desktop-file-name-format 'tilde)
 572      (let ((relative-name (file-relative-name (expand-file-name filename) "~")))
 573        (cond
 574          ((file-name-absolute-p relative-name) relative-name)
 575          ((string= "./" relative-name) "~/")
 576          ((string= "." relative-name) "~")
 577          (t (concat "~/" relative-name)))))
 578     ((eq desktop-file-name-format 'local) (file-relative-name filename dirname))
 579     (t (expand-file-name filename))))
 580
 581 ;; ----------------------------------------------------------------------------
 582 (defun desktop-save (dirname)
 583   "Save the Desktop file. Parameter DIRNAME specifies where to save desktop."
 584   (interactive "DDirectory to save desktop file in: ")
 585   (run-hooks 'desktop-save-hook)
 586   (setq dirname (file-name-as-directory (expand-file-name dirname)))
 587   (save-excursion
 588     (let ((filename (expand-file-name desktop-base-file-name dirname))
 589           (info
 590             (mapcar
 591               (function
 592                 (lambda (b)
 593                   (set-buffer b)
 594                   (list
 595                     (desktop-file-name (buffer-file-name) dirname)
 596                     (buffer-name)
 597                     major-mode
 598                     ;; minor modes
 599                     (let (ret)
 600                       (mapcar
 601                         #'(lambda (mim)
 602                           (and
 603                             (boundp mim)
 604                             (symbol-value mim)
 605                             (setq ret
 606                               (cons
 607                                 (let ((special (assq mim desktop-minor-mode-table)))
 608                                   (if special (cadr special) mim))
 609                                 ret))))
 610                         (mapcar #'car minor-mode-alist))
 611                       ret)
 612                     (point)
 613                     (list (mark t) mark-active)
 614                     buffer-read-only
 615                     (run-hook-with-args-until-success 'desktop-buffer-misc-functions)
 616                     (let ((locals desktop-locals-to-save)
 617                           (loclist (buffer-local-variables))
 618                           (ll))
 619                       (while locals
 620                         (let ((here (assq (car locals) loclist)))
 621                           (if here
 622                             (setq ll (cons here ll))
 623                             (when (member (car locals) loclist)
 624                               (setq ll (cons (car locals) ll)))))
 625                         (setq locals (cdr locals)))
 626                       ll))))
 627               (buffer-list)))
 628           (buf (get-buffer-create "*desktop*")))
 629       (set-buffer buf)
 630       (erase-buffer)
 631
 632       (insert
 633         ";; -*- coding: emacs-mule; -*-\n"
 634         desktop-header
 635         ";; Created " (current-time-string) "\n"
 636         ";; Desktop file format version " desktop-file-version "\n"
 637         ";; Emacs version " emacs-version "\n\n"
 638         ";; Global section:\n")
 639       (mapcar (function desktop-outvar) desktop-globals-to-save)
 640       (if (memq 'kill-ring desktop-globals-to-save)
 641         (insert
 642           "(setq kill-ring-yank-pointer (nthcdr "
 643           (int-to-string (- (length kill-ring) (length kill-ring-yank-pointer)))
 644           " kill-ring))\n"))
 645
 646       (insert "\n;; Buffer section -- buffers listed in same order as in buffer list:\n")
 647       (mapcar
 648         (function
 649           (lambda (l)
 650             (if (apply 'desktop-save-buffer-p l)
 651               (progn
 652                 (insert "(desktop-create-buffer " desktop-file-version)
 653                 (mapcar
 654                   (function
 655                     (lambda (e)
 656                       (insert "\n  " (desktop-value-to-string e))))
 657                   l)
 658                 (insert ")\n\n")))))
 659         info)
 660       (setq default-directory dirname)
 661       (when (file-exists-p filename) (delete-file filename))
 662       (let ((coding-system-for-write 'emacs-mule))
 663         (write-region (point-min) (point-max) filename nil 'nomessage))))
 664   (setq desktop-dirname dirname))
 665
 666 ;; ----------------------------------------------------------------------------
 667 (defun desktop-remove ()
 668   "Delete the Desktop file and inactivate the desktop system."
 669   (interactive)
 670   (if desktop-dirname
 671       (let ((filename (expand-file-name desktop-base-file-name desktop-dirname)))
 672     (setq desktop-dirname nil)
 673     (if (file-exists-p filename)
 674         (delete-file filename)))))
 675 ;; ----------------------------------------------------------------------------
 676 ;;;###autoload
 677 (defun desktop-read ()
 678   "Read the Desktop file and the files it specifies.
 679 This is a no-op when Emacs is running in batch mode.
 680 Look for the desktop file according to the variables `desktop-base-file-name'
 681 and `desktop-path'.  If no desktop file is found, clear the desktop.
 682 Returns t if it has read a desktop file, nil otherwise."
 683   (interactive)
 684   (unless noninteractive
 685     (let ((dirs desktop-path))
 686       (while
 687         (and
 688           dirs
 689           (not
 690             (file-exists-p (expand-file-name desktop-base-file-name (car dirs)))))
 691         (setq dirs (cdr dirs)))
 692       (setq desktop-dirname (and dirs (file-name-as-directory (expand-file-name (car dirs)))))
 693       (if desktop-dirname
 694         (let ((desktop-first-buffer nil))
 695           ;; Evaluate desktop buffer.
 696           (load (expand-file-name desktop-base-file-name desktop-dirname) t t t)
 697           ;; `desktop-create-buffer' puts buffers at end of the buffer list.
 698           ;; We want buffers existing prior to evaluating the desktop (and not reused)
 699           ;; to be placed at the end of the buffer list, so we move them here.
 700           (mapcar 'bury-buffer
 701                   (nreverse (cdr (memq desktop-first-buffer (nreverse (buffer-list))))))
 702           (switch-to-buffer (car (buffer-list)))
 703           (run-hooks 'desktop-delay-hook)
 704           (setq desktop-delay-hook nil)
 705           (run-hooks 'desktop-after-read-hook)
 706           (message "Desktop loaded.")
 707           t)
 708         (desktop-clear)
 709         (run-hooks 'desktop-no-desktop-file-hook)
 710         (message "No desktop file.")
 711         nil))))
 712
 713 ;; ----------------------------------------------------------------------------
 714 ;;;###autoload
 715 (defun desktop-load-default ()
 716   "Load the `default' start-up library manually.
 717 Also inhibit further loading of it.  Call this from your `.emacs' file
 718 to provide correct modes for autoloaded files."
 719   (if (not inhibit-default-init)        ; safety check
 720       (progn
 721         (load "default" t t)
 722         (setq inhibit-default-init t))))
 723
 724 ;; ----------------------------------------------------------------------------
 725 ;;;###autoload
 726 (defun desktop-change-dir (dir)
 727   "Save and clear the desktop, then load the desktop from directory DIR.
 728 However, if `desktop-enable' was nil at call, don't save the old desktop.
 729 This function always sets `desktop-enable' to t."
 730   (interactive "DNew directory: ")
 731   (setq dir (file-name-as-directory (expand-file-name dir desktop-dirname)))
 732   (desktop-kill)
 733   (desktop-clear)
 734   (setq desktop-enable t)
 735   (let ((desktop-path (list dir))
 736         (default-directory dir))
 737     (desktop-read))
 738   ;; Set `desktop-dirname' even in no desktop file was found
 739   (setq desktop-dirname dir))
 740   ;; ----------------------------------------------------------------------------
 741 ;;;###autoload
 742 (defun desktop-save-in-load-dir ()
 743   "Save desktop in directory from which it was loaded."
 744   (interactive)
 745   (if desktop-dirname
 746     (desktop-save desktop-dirname)
 747     (call-interactively 'desktop-save))
 748   (message "Desktop saved in %s" desktop-dirname))
 749
 750 ;; ----------------------------------------------------------------------------
 751 ;;;###autoload
 752 (defun desktop-revert ()
 753   "Revert to the last loaded desktop."
 754   (interactive)
 755   (unless desktop-dirname (error "No desktop has been loaded"))
 756   (setq desktop-enable nil)
 757   (desktop-change-dir desktop-dirname))
 758
 759 ;; ----------------------------------------------------------------------------
 760 ;; Note: the following functions use the dynamic variable binding in Lisp.
 761 ;;
 762
 763 (eval-when-compile ; Just to silence the byte compiler
 764   (defvar desktop-file-version)
 765   (defvar desktop-buffer-file-name)
 766   (defvar desktop-buffer-name)
 767   (defvar desktop-buffer-major-mode)
 768   (defvar desktop-buffer-minor-modes)
 769   (defvar desktop-buffer-point)
 770   (defvar desktop-buffer-mark)
 771   (defvar desktop-buffer-read-only)
 772   (defvar desktop-buffer-misc)
 773   (defvar desktop-buffer-locals)
 774 )
 775
 776 (defun desktop-buffer-info-misc-data ()
 777   (if (eq major-mode 'Info-mode)
 778       (list Info-current-file
 779             Info-current-node)))
 780
 781 ;; ----------------------------------------------------------------------------
 782 (defun desktop-buffer-dired-misc-data ()
 783   (when (eq major-mode 'dired-mode)
 784     (eval-when-compile (defvar dirname))
 785     (cons
 786       ;; dired directory in portable form
 787       (file-name-as-directory (desktop-file-name dired-directory dirname))
 788       (cdr (nreverse (mapcar (function car) dired-subdir-alist))))))
 789
 790 ;; ----------------------------------------------------------------------------
 791 (defun desktop-buffer-info () "Load an info file."
 792   (if (eq 'Info-mode desktop-buffer-major-mode)
 793       (progn
 794         (let ((first (nth 0 desktop-buffer-misc))
 795               (second (nth 1 desktop-buffer-misc)))
 796         (when (and first second)
 797           (require 'info)
 798           (Info-find-node first second)
 799           (current-buffer))))))
 800
 801 ;; ----------------------------------------------------------------------------
 802 (eval-when-compile (defvar rmail-buffer)) ; Just to silence the byte compiler.
 803 (defun desktop-buffer-rmail () "Load an RMAIL file."
 804   (if (eq 'rmail-mode desktop-buffer-major-mode)
 805       (condition-case error
 806           (progn (rmail-input desktop-buffer-file-name)
 807                          (if (eq major-mode 'rmail-mode)
 808                              (current-buffer)
 809                            rmail-buffer))
 810         (file-locked
 811          (kill-buffer (current-buffer))
 812          'ignored))))
 813
 814 ;; ----------------------------------------------------------------------------
 815 (defun desktop-buffer-mh () "Load a folder in the mh system."
 816   (if (eq 'mh-folder-mode desktop-buffer-major-mode)
 817       (progn
 818         (mh-find-path)
 819         (mh-visit-folder desktop-buffer-name)
 820         (current-buffer))))
 821
 822 ;; ----------------------------------------------------------------------------
 823 (defun desktop-buffer-dired () "Load a directory using dired."
 824   (if (eq 'dired-mode desktop-buffer-major-mode)
 825       (if (file-directory-p (file-name-directory (car desktop-buffer-misc)))
 826           (progn
 827             (dired (car desktop-buffer-misc))
 828             (mapcar 'dired-maybe-insert-subdir (cdr desktop-buffer-misc))
 829             (current-buffer))
 830         (message "Directory %s no longer exists." (car desktop-buffer-misc))
 831         (sit-for 1)
 832         'ignored)))
 833
 834 ;; ----------------------------------------------------------------------------
 835 (defun desktop-buffer-file ()
 836   "Load a file."
 837   (if desktop-buffer-file-name
 838       (if (or (file-exists-p desktop-buffer-file-name)
 839               (and desktop-missing-file-warning
 840                    (y-or-n-p (format
 841                               "File \"%s\" no longer exists. Re-create? "
 842                               desktop-buffer-file-name))))
 843           (let ((buf (find-file-noselect desktop-buffer-file-name)))
 844             (condition-case nil
 845                 (switch-to-buffer buf)
 846               (error (pop-to-buffer buf)))
 847             (and (not (eq major-mode desktop-buffer-major-mode))
 848                  (functionp desktop-buffer-major-mode)
 849                  (funcall desktop-buffer-major-mode))
 850             buf)
 851         'ignored)))
 852
 853 ;; ----------------------------------------------------------------------------
 854 ;; Create a buffer, load its file, set is mode, ...;  called from Desktop file
 855 ;; only.
 856
 857 (eval-when-compile ; Just to silence the byte compiler
 858    (defvar desktop-first-buffer) ;; Dynamically bound in `desktop-read'
 859 )
 860
 861 (defun desktop-create-buffer (
 862   desktop-file-version
 863   desktop-buffer-file-name
 864   desktop-buffer-name
 865   desktop-buffer-major-mode
 866   desktop-buffer-minor-modes
 867   desktop-buffer-point
 868   desktop-buffer-mark
 869   desktop-buffer-read-only
 870   desktop-buffer-misc
 871   &optional
 872   desktop-buffer-locals)
 873   ;; To make desktop files with relative file names possible, we cannot
 874   ;; allow `default-directory' to change. Therefore we save current buffer.
 875   (save-current-buffer
 876     (let (
 877       (buffer-list (buffer-list))
 878       (hlist desktop-buffer-handlers)
 879       (result)
 880       (handler)
 881     )
 882       ;; Call desktop-buffer-handlers to create buffer.
 883       (while (and (not result) hlist)
 884         (setq handler (car hlist))
 885         (setq result (funcall handler))
 886         (setq hlist (cdr hlist)))
 887       (unless (bufferp result) (setq result nil))
 888       ;; Restore buffer list order with new buffer at end. Don't change
 889       ;; the order for old desktop files (old desktop module behaviour).
 890       (unless (< desktop-file-version 206)
 891         (mapcar 'bury-buffer buffer-list)
 892         (when result (bury-buffer result)))
 893       (when result
 894         (unless (or desktop-first-buffer (< desktop-file-version 206))
 895           (setq desktop-first-buffer result))
 896         (set-buffer result)
 897         (unless (equal (buffer-name) desktop-buffer-name)
 898           (rename-buffer desktop-buffer-name))
 899         ;; minor modes
 900         (cond (
 901           ;; backwards compatible
 902           (equal '(t) desktop-buffer-minor-modes)
 903           (auto-fill-mode 1))(
 904           (equal '(nil) desktop-buffer-minor-modes)
 905           (auto-fill-mode 0))(
 906           t
 907           (mapcar
 908             #'(lambda (minor-mode)
 909               (when (functionp minor-mode) (funcall minor-mode 1)))
 910             desktop-buffer-minor-modes)))
 911         ;; Even though point and mark are non-nil when written by `desktop-save'
 912         ;; they may be modified by handlers wanting to set point or mark themselves.
 913         (when desktop-buffer-point (goto-char desktop-buffer-point))
 914         (when desktop-buffer-mark
 915           (if (consp desktop-buffer-mark)
 916             (progn
 917               (set-mark (car desktop-buffer-mark))
 918               (setq mark-active (car (cdr desktop-buffer-mark))))
 919             (set-mark desktop-buffer-mark)))
 920         ;; Never override file system if the file really is read-only marked.
 921         (if desktop-buffer-read-only (setq buffer-read-only desktop-buffer-read-only))
 922         (while desktop-buffer-locals
 923           (let ((this (car desktop-buffer-locals)))
 924             (if (consp this)
 925               ;; an entry of this form `(symbol . value)'
 926               (progn
 927                 (make-local-variable (car this))
 928                 (set (car this) (cdr this)))
 929               ;; an entry of the form `symbol'
 930               (make-local-variable this)
 931               (makunbound this)))
 932           (setq desktop-buffer-locals (cdr desktop-buffer-locals)))))))
 933
 934 ;; ----------------------------------------------------------------------------
 935 ;; Backward compatibility -- update parameters to 205 standards.
 936 (defun desktop-buffer (desktop-buffer-file-name desktop-buffer-name
 937                        desktop-buffer-major-mode
 938                        mim pt mk ro tl fc cfs cr desktop-buffer-misc)
 939   (desktop-create-buffer 205 desktop-buffer-file-name desktop-buffer-name
 940                          desktop-buffer-major-mode (cdr mim) pt mk ro
 941                          desktop-buffer-misc
 942                          (list (cons 'truncate-lines tl)
 943                                (cons 'fill-column fc)
 944                                (cons 'case-fold-search cfs)
 945                                (cons 'case-replace cr)
 946                                (cons 'overwrite-mode (car mim)))))
 947
 948 ;; ----------------------------------------------------------------------------
 949 ;; When `desktop-enable' is non-nil and "--no-desktop" is not specified on the
 950 ;; command line, we do the rest of what it takes to use desktop, but do it
 951 ;; after finishing loading the init file.
 952 ;; We cannot use `command-switch-alist' to process "--no-desktop" because these
 953 ;; functions are processed after `after-init-hook'.
 954 (add-hook
 955   'after-init-hook
 956   '(lambda ()
 957     (let ((key "--no-desktop"))
 958       (if (member key command-line-args)
 959         (delete key command-line-args)
 960         (when desktop-enable
 961           (desktop-load-default)
 962           (desktop-read))))))
 963
 964 (provide 'desktop)
 965
 966 ;;; desktop.el ends here