lisp/desktop.el

   1 ;;; desktop.el --- save partial status of Emacs when killed
   2
   3 ;; Copyright (C) 1993-1995, 1997, 2000-2011  Free Software Foundation, Inc.
   4
   5 ;; Author: Morten Welinder <terra@diku.dk>
   6 ;; Keywords: convenience
   7 ;; Favourite-brand-of-beer: None, I hate beer.
   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 ;; Save the Desktop, i.e.,
  27 ;;      - some global variables
  28 ;;      - the list of buffers with associated files.  For each buffer also
  29 ;;              - the major mode
  30 ;;              - the default directory
  31 ;;              - the point
  32 ;;              - the mark & mark-active
  33 ;;              - buffer-read-only
  34 ;;              - some local variables
  35
  36 ;; To use this, use customize to turn on desktop-save-mode or add the
  37 ;; following line somewhere in your .emacs file:
  38 ;;
  39 ;;      (desktop-save-mode 1)
  40 ;;
  41 ;; For further usage information, look at the section
  42 ;; (info "(emacs)Saving Emacs Sessions") in the GNU Emacs Manual.
  43
  44 ;; When the desktop module is loaded, the function `desktop-kill' is
  45 ;; added to the `kill-emacs-hook'.  This function is responsible for
  46 ;; saving the desktop when Emacs is killed.  Furthermore an anonymous
  47 ;; function is added to the `after-init-hook'.  This function is
  48 ;; responsible for loading the desktop when Emacs is started.
  49
  50 ;; Special handling.
  51 ;; -----------------
  52 ;; Variables `desktop-buffer-mode-handlers' and `desktop-minor-mode-handlers'
  53 ;; are supplied to handle special major and minor modes respectively.
  54 ;; `desktop-buffer-mode-handlers' is an alist of major mode specific functions
  55 ;; to restore a desktop buffer.  Elements must have the form
  56 ;;
  57 ;;    (MAJOR-MODE . RESTORE-BUFFER-FUNCTION).
  58 ;;
  59 ;; Functions listed are called by `desktop-create-buffer' when `desktop-read'
  60 ;; evaluates the desktop file.  Buffers with a major mode not specified here,
  61 ;; are restored by the default handler `desktop-restore-file-buffer'.
  62 ;; `desktop-minor-mode-handlers' is an alist of functions to restore
  63 ;; non-standard minor modes.  Elements must have the form
  64 ;;
  65 ;;    (MINOR-MODE . RESTORE-FUNCTION).
  66 ;;
  67 ;; Functions are called by `desktop-create-buffer' to restore minor modes.
  68 ;; Minor modes not specified here, are restored by the standard minor mode
  69 ;; function.  If you write a module that defines a major or minor mode that
  70 ;; needs a special handler, then place code like
  71
  72 ;;    (defun foo-restore-desktop-buffer
  73 ;;    ...
  74 ;;    (add-to-list 'desktop-buffer-mode-handlers
  75 ;;                 '(foo-mode . foo-restore-desktop-buffer))
  76
  77 ;; or
  78
  79 ;;    (defun bar-desktop-restore
  80 ;;    ...
  81 ;;    (add-to-list 'desktop-minor-mode-handlers
  82 ;;                 '(bar-mode . bar-desktop-restore))
  83
  84 ;; in the module itself, and make sure that the mode function is
  85 ;; autoloaded.  See the docstrings of `desktop-buffer-mode-handlers' and
  86 ;; `desktop-minor-mode-handlers' for more info.
  87
  88 ;; Minor modes.
  89 ;; ------------
  90 ;; Conventional minor modes (see node "Minor Mode Conventions" in the elisp
  91 ;; manual) are handled in the following way:
  92 ;; When `desktop-save' saves the state of a buffer to the desktop file, it
  93 ;; saves as `desktop-minor-modes' the list of names of those variables in
  94 ;; `minor-mode-alist' that have a non-nil value.
  95 ;; When `desktop-create' restores the buffer, each of the symbols in
  96 ;; `desktop-minor-modes' is called as function with parameter 1.
  97 ;; The variables `desktop-minor-mode-table' and `desktop-minor-mode-handlers'
  98 ;; are used to handle non-conventional minor modes.  `desktop-save' uses
  99 ;; `desktop-minor-mode-table' to map minor mode variables to minor mode
 100 ;; functions before writing `desktop-minor-modes'.  If a minor mode has a
 101 ;; variable name that is different form its function name, an entry
 102
 103 ;;    (NAME RESTORE-FUNCTION)
 104
 105 ;; should be added to `desktop-minor-mode-table'.  If a minor mode should not
 106 ;; be restored, RESTORE-FUNCTION should be set to nil.  `desktop-create' uses
 107 ;; `desktop-minor-mode-handlers' to lookup minor modes that needs a restore
 108 ;; function different from the usual minor mode function.
 109 ;; ---------------------------------------------------------------------------
 110
 111 ;; By the way: don't use desktop.el to customize Emacs -- the file .emacs
 112 ;; in your home directory is used for that.  Saving global default values
 113 ;; for buffers is an example of misuse.
 114
 115 ;; PLEASE NOTE: The kill ring can be saved as specified by the variable
 116 ;; `desktop-globals-to-save' (by default it isn't).  This may result in saving
 117 ;; things you did not mean to keep.  Use M-x desktop-clear RET.
 118
 119 ;; Thanks to  hetrick@phys.uva.nl (Jim Hetrick)      for useful ideas.
 120 ;;            avk@rtsg.mot.com (Andrew V. Klein)     for a dired tip.
 121 ;;            chris@tecc.co.uk (Chris Boucher)       for a mark tip.
 122 ;;            f89-kam@nada.kth.se (Klas Mellbourn)   for a mh-e tip.
 123 ;;            kifer@sbkifer.cs.sunysb.edu (M. Kifer) for a bug hunt.
 124 ;;            treese@lcs.mit.edu (Win Treese)        for ange-ftp tips.
 125 ;;            pot@cnuce.cnr.it (Francesco Potorti`)  for misc. tips.
 126 ;; ---------------------------------------------------------------------------
 127 ;; TODO:
 128 ;;
 129 ;; Save window configuration.
 130 ;; Recognize more minor modes.
 131 ;; Save mark rings.
 132
 133 ;;; Code:
 134
 135 (defvar desktop-file-version "206"
 136   "Version number of desktop file format.
 137 Written into the desktop file and used at desktop read to provide
 138 backward compatibility.")
 139
 140 ;; ----------------------------------------------------------------------------
 141 ;; USER OPTIONS -- settings you might want to play with.
 142 ;; ----------------------------------------------------------------------------
 143
 144 (defgroup desktop nil
 145   "Save status of Emacs when you exit."
 146   :group 'frames)
 147
 148 ;;;###autoload
 149 (define-minor-mode desktop-save-mode
 150   "Toggle desktop saving mode.
 151 With numeric ARG, turn desktop saving on if ARG is positive, off
 152 otherwise.  If desktop saving is turned on, the state of Emacs is
 153 saved from one session to another.  See variable `desktop-save'
 154 and function `desktop-read' for details."
 155   :global t
 156   :group 'desktop)
 157
 158 ;; Maintained for backward compatibility
 159 (define-obsolete-variable-alias 'desktop-enable
 160                                 'desktop-save-mode "22.1")
 161
 162 (defun desktop-save-mode-off ()
 163   "Disable `desktop-save-mode'.  Provided for use in hooks."
 164   (desktop-save-mode 0))
 165
 166 (defcustom desktop-save 'ask-if-new
 167   "Specifies whether the desktop should be saved when it is killed.
 168 A desktop is killed when the user changes desktop or quits Emacs.
 169 Possible values are:
 170    t             -- always save.
 171    ask           -- always ask.
 172    ask-if-new    -- ask if no desktop file exists, otherwise just save.
 173    ask-if-exists -- ask if desktop file exists, otherwise don't save.
 174    if-exists     -- save if desktop file exists, otherwise don't save.
 175    nil           -- never save.
 176 The desktop is never saved when `desktop-save-mode' is nil.
 177 The variables `desktop-dirname' and `desktop-base-file-name'
 178 determine where the desktop is saved."
 179   :type
 180   '(choice
 181     (const :tag "Always save" t)
 182     (const :tag "Always ask" ask)
 183     (const :tag "Ask if desktop file is new, else do save" ask-if-new)
 184     (const :tag "Ask if desktop file exists, else don't save" ask-if-exists)
 185     (const :tag "Save if desktop file exists, else don't" if-exists)
 186     (const :tag "Never save" nil))
 187   :group 'desktop
 188   :version "22.1")
 189
 190 (defcustom desktop-load-locked-desktop 'ask
 191   "Specifies whether the desktop should be loaded if locked.
 192 Possible values are:
 193    t    -- load anyway.
 194    nil  -- don't load.
 195    ask  -- ask the user.
 196 If the value is nil, or `ask' and the user chooses not to load the desktop,
 197 the normal hook `desktop-not-loaded-hook' is run."
 198   :type
 199   '(choice
 200     (const :tag "Load anyway" t)
 201     (const :tag "Don't load" nil)
 202     (const :tag "Ask the user" ask))
 203   :group 'desktop
 204   :version "22.2")
 205
 206 (define-obsolete-variable-alias 'desktop-basefilename
 207                                 'desktop-base-file-name "22.1")
 208
 209 (defcustom desktop-base-file-name
 210   (convert-standard-filename ".emacs.desktop")
 211   "Name of file for Emacs desktop, excluding the directory part."
 212   :type 'file
 213   :group 'desktop)
 214
 215 (defcustom desktop-base-lock-name
 216   (convert-standard-filename ".emacs.desktop.lock")
 217   "Name of lock file for Emacs desktop, excluding the directory part."
 218   :type 'file
 219   :group 'desktop
 220   :version "22.2")
 221
 222 (defcustom desktop-path (list "." user-emacs-directory "~")
 223   "List of directories to search for the desktop file.
 224 The base name of the file is specified in `desktop-base-file-name'."
 225   :type '(repeat directory)
 226   :group 'desktop
 227   :version "23.2")                      ; user-emacs-directory added
 228
 229 (defcustom desktop-missing-file-warning nil
 230   "If non-nil, offer to recreate the buffer of a deleted file.
 231 Also pause for a moment to display message about errors signaled in
 232 `desktop-buffer-mode-handlers'.
 233
 234 If nil, just print error messages in the message buffer."
 235   :type 'boolean
 236   :group 'desktop
 237   :version "22.1")
 238
 239 (defcustom desktop-no-desktop-file-hook nil
 240   "Normal hook run when `desktop-read' can't find a desktop file.
 241 Run in the directory in which the desktop file was sought.
 242 May be used to show a dired buffer."
 243   :type 'hook
 244   :group 'desktop
 245   :version "22.1")
 246
 247 (defcustom desktop-not-loaded-hook nil
 248   "Normal hook run when the user declines to re-use a desktop file.
 249 Run in the directory in which the desktop file was found.
 250 May be used to deal with accidental multiple Emacs jobs."
 251   :type 'hook
 252   :group 'desktop
 253   :options '(desktop-save-mode-off save-buffers-kill-emacs)
 254   :version "22.2")
 255
 256 (defcustom desktop-after-read-hook nil
 257   "Normal hook run after a successful `desktop-read'.
 258 May be used to show a buffer list."
 259   :type 'hook
 260   :group 'desktop
 261   :options '(list-buffers)
 262   :version "22.1")
 263
 264 (defcustom desktop-save-hook nil
 265   "Normal hook run before the desktop is saved in a desktop file.
 266 Run with the desktop buffer current with only the header present.
 267 May be used to add to the desktop code or to truncate history lists,
 268 for example."
 269   :type 'hook
 270   :group 'desktop)
 271
 272 (defcustom desktop-globals-to-save
 273   '(desktop-missing-file-warning
 274     tags-file-name
 275     tags-table-list
 276     search-ring
 277     regexp-search-ring
 278     register-alist
 279     file-name-history)
 280   "List of global variables saved by `desktop-save'.
 281 An element may be variable name (a symbol) or a cons cell of the form
 282 \(VAR . MAX-SIZE), which means to truncate VAR's value to at most
 283 MAX-SIZE elements (if the value is a list) before saving the value.
 284 Feature: Saving `kill-ring' implies saving `kill-ring-yank-pointer'."
 285   :type '(repeat (restricted-sexp :match-alternatives (symbolp consp)))
 286   :group 'desktop)
 287
 288 (defcustom desktop-globals-to-clear
 289   '(kill-ring
 290     kill-ring-yank-pointer
 291     search-ring
 292     search-ring-yank-pointer
 293     regexp-search-ring
 294     regexp-search-ring-yank-pointer)
 295   "List of global variables that `desktop-clear' will clear.
 296 An element may be variable name (a symbol) or a cons cell of the form
 297 \(VAR . FORM).  Symbols are set to nil and for cons cells VAR is set
 298 to the value obtained by evaluating FORM."
 299   :type '(repeat (restricted-sexp :match-alternatives (symbolp consp)))
 300   :group 'desktop
 301   :version "22.1")
 302
 303 (defcustom desktop-clear-preserve-buffers
 304   '("\\*scratch\\*" "\\*Messages\\*" "\\*server\\*" "\\*tramp/.+\\*"
 305     "\\*Warnings\\*")
 306   "List of buffers that `desktop-clear' should not delete.
 307 Each element is a regular expression.  Buffers with a name matched by any of
 308 these won't be deleted."
 309   :version "23.3"                       ; added Warnings - bug#6336
 310   :type '(repeat string)
 311   :group 'desktop)
 312
 313 ;;;###autoload
 314 (defcustom desktop-locals-to-save
 315   '(desktop-locals-to-save  ; Itself!  Think it over.
 316     truncate-lines
 317     case-fold-search
 318     case-replace
 319     fill-column
 320     overwrite-mode
 321     change-log-default-name
 322     line-number-mode
 323     column-number-mode
 324     size-indication-mode
 325     buffer-file-coding-system
 326     indent-tabs-mode
 327     tab-width
 328     indicate-buffer-boundaries
 329     indicate-empty-lines
 330     show-trailing-whitespace)
 331   "List of local variables to save for each buffer.
 332 The variables are saved only when they really are local.  Conventional minor
 333 modes are restored automatically; they should not be listed here."
 334   :type '(repeat symbol)
 335   :group 'desktop)
 336
 337 (defcustom desktop-buffers-not-to-save nil
 338   "Regexp identifying buffers that are to be excluded from saving."
 339   :type '(choice (const :tag "None" nil)
 340                  regexp)
 341   :version "23.2"                       ; set to nil
 342   :group 'desktop)
 343
 344 ;; Skip tramp and ange-ftp files
 345 (defcustom desktop-files-not-to-save
 346   "\\(^/[^/:]*:\\|(ftp)$\\)"
 347   "Regexp identifying files whose buffers are to be excluded from saving."
 348   :type '(choice (const :tag "None" nil)
 349                  regexp)
 350   :group 'desktop)
 351
 352 ;; We skip TAGS files to save time (tags-file-name is saved instead).
 353 (defcustom desktop-modes-not-to-save
 354   '(tags-table-mode)
 355   "List of major modes whose buffers should not be saved."
 356   :type '(repeat symbol)
 357   :group 'desktop)
 358
 359 (defcustom desktop-file-name-format 'absolute
 360   "Format in which desktop file names should be saved.
 361 Possible values are:
 362    absolute -- Absolute file name.
 363    tilde    -- Relative to ~.
 364    local    -- Relative to directory of desktop file."
 365   :type '(choice (const absolute) (const tilde) (const local))
 366   :group 'desktop
 367   :version "22.1")
 368
 369 (defcustom desktop-restore-eager t
 370   "Number of buffers to restore immediately.
 371 Remaining buffers are restored lazily (when Emacs is idle).
 372 If value is t, all buffers are restored immediately."
 373   :type '(choice (const t) integer)
 374   :group 'desktop
 375   :version "22.1")
 376
 377 (defcustom desktop-lazy-verbose t
 378   "Verbose reporting of lazily created buffers."
 379   :type 'boolean
 380   :group 'desktop
 381   :version "22.1")
 382
 383 (defcustom desktop-lazy-idle-delay 5
 384   "Idle delay before starting to create buffers.
 385 See `desktop-restore-eager'."
 386   :type 'integer
 387   :group 'desktop
 388   :version "22.1")
 389
 390 ;;;###autoload
 391 (defvar desktop-save-buffer nil
 392   "When non-nil, save buffer status in desktop file.
 393 This variable becomes buffer local when set.
 394
 395 If the value is a function, it is called by `desktop-save' with argument
 396 DESKTOP-DIRNAME to obtain auxiliary information to save in the desktop
 397 file along with the state of the buffer for which it was called.
 398
 399 When file names are returned, they should be formatted using the call
 400 \"(desktop-file-name FILE-NAME DESKTOP-DIRNAME)\".
 401
 402 Later, when `desktop-read' evaluates the desktop file, auxiliary information
 403 is passed as the argument DESKTOP-BUFFER-MISC to functions in
 404 `desktop-buffer-mode-handlers'.")
 405 (make-variable-buffer-local 'desktop-save-buffer)
 406 (make-obsolete-variable 'desktop-buffer-modes-to-save
 407                         'desktop-save-buffer "22.1")
 408 (make-obsolete-variable 'desktop-buffer-misc-functions
 409                         'desktop-save-buffer "22.1")
 410
 411 ;;;###autoload
 412 (defvar desktop-buffer-mode-handlers
 413   nil
 414   "Alist of major mode specific functions to restore a desktop buffer.
 415 Functions listed are called by `desktop-create-buffer' when `desktop-read'
 416 evaluates the desktop file.  List elements must have the form
 417
 418    (MAJOR-MODE . RESTORE-BUFFER-FUNCTION).
 419
 420 Buffers with a major mode not specified here, are restored by the default
 421 handler `desktop-restore-file-buffer'.
 422
 423 Handlers are called with argument list
 424
 425    (DESKTOP-BUFFER-FILE-NAME DESKTOP-BUFFER-NAME DESKTOP-BUFFER-MISC)
 426
 427 Furthermore, they may use the following variables:
 428
 429    desktop-file-version
 430    desktop-buffer-major-mode
 431    desktop-buffer-minor-modes
 432    desktop-buffer-point
 433    desktop-buffer-mark
 434    desktop-buffer-read-only
 435    desktop-buffer-locals
 436
 437 If a handler returns a buffer, then the saved mode settings
 438 and variable values for that buffer are copied into it.
 439
 440 Modules that define a major mode that needs a special handler should contain
 441 code like
 442
 443    (defun foo-restore-desktop-buffer
 444    ...
 445    (add-to-list 'desktop-buffer-mode-handlers
 446                 '(foo-mode . foo-restore-desktop-buffer))
 447
 448 Furthermore the major mode function must be autoloaded.")
 449
 450 ;;;###autoload
 451 (put 'desktop-buffer-mode-handlers 'risky-local-variable t)
 452 (make-obsolete-variable 'desktop-buffer-handlers
 453                         'desktop-buffer-mode-handlers "22.1")
 454
 455 (defcustom desktop-minor-mode-table
 456   '((auto-fill-function auto-fill-mode)
 457     (vc-mode nil)
 458     (vc-dired-mode nil)
 459     (erc-track-minor-mode nil)
 460     (savehist-mode nil))
 461   "Table mapping minor mode variables to minor mode functions.
 462 Each entry has the form (NAME RESTORE-FUNCTION).
 463 NAME is the name of the buffer-local variable indicating that the minor
 464 mode is active.  RESTORE-FUNCTION is the function to activate the minor mode.
 465 RESTORE-FUNCTION nil means don't try to restore the minor mode.
 466 Only minor modes for which the name of the buffer-local variable
 467 and the name of the minor mode function are different have to be added to
 468 this table.  See also `desktop-minor-mode-handlers'."
 469   :type 'sexp
 470   :group 'desktop)
 471
 472 ;;;###autoload
 473 (defvar desktop-minor-mode-handlers
 474   nil
 475   "Alist of functions to restore non-standard minor modes.
 476 Functions are called by `desktop-create-buffer' to restore minor modes.
 477 List elements must have the form
 478
 479    (MINOR-MODE . RESTORE-FUNCTION).
 480
 481 Minor modes not specified here, are restored by the standard minor mode
 482 function.
 483
 484 Handlers are called with argument list
 485
 486    (DESKTOP-BUFFER-LOCALS)
 487
 488 Furthermore, they may use the following variables:
 489
 490    desktop-file-version
 491    desktop-buffer-file-name
 492    desktop-buffer-name
 493    desktop-buffer-major-mode
 494    desktop-buffer-minor-modes
 495    desktop-buffer-point
 496    desktop-buffer-mark
 497    desktop-buffer-read-only
 498    desktop-buffer-misc
 499
 500 When a handler is called, the buffer has been created and the major mode has
 501 been set, but local variables listed in desktop-buffer-locals has not yet been
 502 created and set.
 503
 504 Modules that define a minor mode that needs a special handler should contain
 505 code like
 506
 507    (defun foo-desktop-restore
 508    ...
 509    (add-to-list 'desktop-minor-mode-handlers
 510                 '(foo-mode . foo-desktop-restore))
 511
 512 Furthermore the minor mode function must be autoloaded.
 513
 514 See also `desktop-minor-mode-table'.")
 515
 516 ;;;###autoload
 517 (put 'desktop-minor-mode-handlers 'risky-local-variable t)
 518
 519 ;; ----------------------------------------------------------------------------
 520 (defvar desktop-dirname nil
 521   "The directory in which the desktop file should be saved.")
 522
 523 (defun desktop-full-file-name (&optional dirname)
 524   "Return the full name of the desktop file in DIRNAME.
 525 DIRNAME omitted or nil means use `desktop-dirname'."
 526   (expand-file-name desktop-base-file-name (or dirname desktop-dirname)))
 527
 528 (defun desktop-full-lock-name (&optional dirname)
 529   "Return the full name of the desktop lock file in DIRNAME.
 530 DIRNAME omitted or nil means use `desktop-dirname'."
 531   (expand-file-name desktop-base-lock-name (or dirname desktop-dirname)))
 532
 533 (defconst desktop-header
 534 ";; --------------------------------------------------------------------------
 535 ;; Desktop File for Emacs
 536 ;; --------------------------------------------------------------------------
 537 " "*Header to place in Desktop file.")
 538
 539 (defvar desktop-delay-hook nil
 540   "Hooks run after all buffers are loaded; intended for internal use.")
 541
 542 ;; ----------------------------------------------------------------------------
 543 ;; Desktop file conflict detection
 544 (defvar desktop-file-modtime nil
 545   "When the desktop file was last modified to the knowledge of this Emacs.
 546 Used to detect desktop file conflicts.")
 547
 548 (defun desktop-owner (&optional dirname)
 549   "Return the PID of the Emacs process that owns the desktop file in DIRNAME.
 550 Return nil if no desktop file found or no Emacs process is using it.
 551 DIRNAME omitted or nil means use `desktop-dirname'."
 552   (let (owner)
 553     (and (file-exists-p (desktop-full-lock-name dirname))
 554          (condition-case nil
 555              (with-temp-buffer
 556                (insert-file-contents-literally (desktop-full-lock-name dirname))
 557                (goto-char (point-min))
 558                (setq owner (read (current-buffer)))
 559                (integerp owner))
 560            (error nil))
 561          owner)))
 562
 563 (defun desktop-claim-lock (&optional dirname)
 564   "Record this Emacs process as the owner of the desktop file in DIRNAME.
 565 DIRNAME omitted or nil means use `desktop-dirname'."
 566   (write-region (number-to-string (emacs-pid)) nil
 567                 (desktop-full-lock-name dirname)))
 568
 569 (defun desktop-release-lock (&optional dirname)
 570   "Remove the lock file for the desktop in DIRNAME.
 571 DIRNAME omitted or nil means use `desktop-dirname'."
 572   (let ((file (desktop-full-lock-name dirname)))
 573     (when (file-exists-p file) (delete-file file))))
 574
 575 ;; ----------------------------------------------------------------------------
 576 (defun desktop-truncate (list n)
 577   "Truncate LIST to at most N elements destructively."
 578   (let ((here (nthcdr (1- n) list)))
 579     (when (consp here)
 580       (setcdr here nil))))
 581
 582 ;; ----------------------------------------------------------------------------
 583 ;;;###autoload
 584 (defun desktop-clear ()
 585   "Empty the Desktop.
 586 This kills all buffers except for internal ones and those with names matched by
 587 a regular expression in the list `desktop-clear-preserve-buffers'.
 588 Furthermore, it clears the variables listed in `desktop-globals-to-clear'."
 589   (interactive)
 590   (desktop-lazy-abort)
 591   (dolist (var desktop-globals-to-clear)
 592     (if (symbolp var)
 593         (eval `(setq-default ,var nil))
 594       (eval `(setq-default ,(car var) ,(cdr var)))))
 595   (let ((buffers (buffer-list))
 596         (preserve-regexp (concat "^\\("
 597                                  (mapconcat (lambda (regexp)
 598                                               (concat "\\(" regexp "\\)"))
 599                                             desktop-clear-preserve-buffers
 600                                             "\\|")
 601                                  "\\)$")))
 602     (while buffers
 603       (let ((bufname (buffer-name (car buffers))))
 604          (or
 605            (null bufname)
 606            (string-match preserve-regexp bufname)
 607            ;; Don't kill buffers made for internal purposes.
 608            (and (not (equal bufname "")) (eq (aref bufname 0) ?\s))
 609            (kill-buffer (car buffers))))
 610       (setq buffers (cdr buffers))))
 611   (delete-other-windows))
 612
 613 ;; ----------------------------------------------------------------------------
 614 (add-hook 'kill-emacs-hook 'desktop-kill)
 615
 616 (defun desktop-kill ()
 617   "If `desktop-save-mode' is non-nil, do what `desktop-save' says to do.
 618 If the desktop should be saved and `desktop-dirname'
 619 is nil, ask the user where to save the desktop."
 620   (when (and desktop-save-mode
 621              (let ((exists (file-exists-p (desktop-full-file-name))))
 622                (or (eq desktop-save t)
 623                    (and exists (eq desktop-save 'if-exists))
 624                    ;; If it exists, but we aren't using it, we are going
 625                    ;; to ask for a new directory below.
 626                    (and exists desktop-dirname (eq desktop-save 'ask-if-new))
 627                    (and
 628                     (or (memq desktop-save '(ask ask-if-new))
 629                         (and exists (eq desktop-save 'ask-if-exists)))
 630                     (y-or-n-p "Save desktop? ")))))
 631     (unless desktop-dirname
 632       (setq desktop-dirname
 633             (file-name-as-directory
 634              (expand-file-name
 635               (read-directory-name "Directory for desktop file: " nil nil t)))))
 636     (condition-case err
 637         (desktop-save desktop-dirname t)
 638       (file-error
 639        (unless (yes-or-no-p "Error while saving the desktop.  Ignore? ")
 640          (signal (car err) (cdr err))))))
 641   ;; If we own it, we don't anymore.
 642   (when (eq (emacs-pid) (desktop-owner)) (desktop-release-lock)))
 643
 644 ;; ----------------------------------------------------------------------------
 645 (defun desktop-list* (&rest args)
 646   (if (null (cdr args))
 647       (car args)
 648     (setq args (nreverse args))
 649     (let ((value (cons (nth 1 args) (car args))))
 650       (setq args (cdr (cdr args)))
 651       (while args
 652         (setq value (cons (car args) value))
 653         (setq args (cdr args)))
 654       value)))
 655
 656 ;; ----------------------------------------------------------------------------
 657 (defun desktop-buffer-info (buffer)
 658   (set-buffer buffer)
 659   (list
 660    ;; base name of the buffer; replaces the buffer name if managed by uniquify
 661    (and (fboundp 'uniquify-buffer-base-name) (uniquify-buffer-base-name))
 662    ;; basic information
 663    (desktop-file-name (buffer-file-name) desktop-dirname)
 664    (buffer-name)
 665    major-mode
 666    ;; minor modes
 667    (let (ret)
 668      (mapc
 669       #'(lambda (minor-mode)
 670           (and (boundp minor-mode)
 671                (symbol-value minor-mode)
 672                (let* ((special (assq minor-mode desktop-minor-mode-table))
 673                       (value (cond (special (cadr special))
 674                                    ((functionp minor-mode) minor-mode))))
 675                  (when value (add-to-list 'ret value)))))
 676       (mapcar #'car minor-mode-alist))
 677      ret)
 678    ;; point and mark, and read-only status
 679    (point)
 680    (list (mark t) mark-active)
 681    buffer-read-only
 682    ;; auxiliary information
 683    (when (functionp desktop-save-buffer)
 684      (funcall desktop-save-buffer desktop-dirname))
 685    ;; local variables
 686    (let ((locals desktop-locals-to-save)
 687          (loclist (buffer-local-variables))
 688          (ll))
 689      (while locals
 690        (let ((here (assq (car locals) loclist)))
 691          (if here
 692              (setq ll (cons here ll))
 693            (when (member (car locals) loclist)
 694              (setq ll (cons (car locals) ll)))))
 695        (setq locals (cdr locals)))
 696      ll)))
 697
 698 ;; ----------------------------------------------------------------------------
 699 (defun desktop-internal-v2s (value)
 700   "Convert VALUE to a pair (QUOTE . TXT); (eval (read TXT)) gives VALUE.
 701 TXT is a string that when read and evaluated yields value.
 702 QUOTE may be `may' (value may be quoted),
 703 `must' (values must be quoted), or nil (value may not be quoted)."
 704   (cond
 705     ((or (numberp value) (null value) (eq t value) (keywordp value))
 706      (cons 'may (prin1-to-string value)))
 707     ((stringp value)
 708      (let ((copy (copy-sequence value)))
 709        (set-text-properties 0 (length copy) nil copy)
 710        ;; Get rid of text properties because we cannot read them
 711        (cons 'may (prin1-to-string copy))))
 712     ((symbolp value)
 713      (cons 'must (prin1-to-string value)))
 714     ((vectorp value)
 715      (let* ((special nil)
 716             (pass1 (mapcar
 717                     (lambda (el)
 718                       (let ((res (desktop-internal-v2s el)))
 719                         (if (null (car res))
 720                             (setq special t))
 721                         res))
 722                     value)))
 723        (if special
 724            (cons nil (concat "(vector "
 725                              (mapconcat (lambda (el)
 726                                           (if (eq (car el) 'must)
 727                                               (concat "'" (cdr el))
 728                                             (cdr el)))
 729                                         pass1
 730                                         " ")
 731                              ")"))
 732          (cons 'may (concat "[" (mapconcat 'cdr pass1 " ") "]")))))
 733     ((consp value)
 734      (let ((p value)
 735            newlist
 736            use-list*
 737            anynil)
 738        (while (consp p)
 739          (let ((q.txt (desktop-internal-v2s (car p))))
 740            (or anynil (setq anynil (null (car q.txt))))
 741            (setq newlist (cons q.txt newlist)))
 742          (setq p (cdr p)))
 743        (if p
 744            (let ((last (desktop-internal-v2s p)))
 745              (or anynil (setq anynil (null (car last))))
 746              (or anynil
 747                  (setq newlist (cons '(must . ".") newlist)))
 748              (setq use-list* t)
 749              (setq newlist (cons last newlist))))
 750        (setq newlist (nreverse newlist))
 751        (if anynil
 752            (cons nil
 753                  (concat (if use-list* "(desktop-list* "  "(list ")
 754                          (mapconcat (lambda (el)
 755                                       (if (eq (car el) 'must)
 756                                           (concat "'" (cdr el))
 757                                         (cdr el)))
 758                                     newlist
 759                                     " ")
 760                          ")"))
 761          (cons 'must
 762                (concat "(" (mapconcat 'cdr newlist " ") ")")))))
 763     ((subrp value)
 764      (cons nil (concat "(symbol-function '"
 765                        (substring (prin1-to-string value) 7 -1)
 766                        ")")))
 767     ((markerp value)
 768      (let ((pos (prin1-to-string (marker-position value)))
 769            (buf (prin1-to-string (buffer-name (marker-buffer value)))))
 770        (cons nil (concat "(let ((mk (make-marker)))"
 771                          " (add-hook 'desktop-delay-hook"
 772                          " (list 'lambda '() (list 'set-marker mk "
 773                          pos " (get-buffer " buf ")))) mk)"))))
 774     (t                                   ; save as text
 775      (cons 'may "\"Unprintable entity\""))))
 776
 777 ;; ----------------------------------------------------------------------------
 778 (defun desktop-value-to-string (value)
 779   "Convert VALUE to a string that when read evaluates to the same value.
 780 Not all types of values are supported."
 781   (let* ((print-escape-newlines t)
 782          (float-output-format nil)
 783          (quote.txt (desktop-internal-v2s value))
 784          (quote (car quote.txt))
 785          (txt (cdr quote.txt)))
 786     (if (eq quote 'must)
 787         (concat "'" txt)
 788       txt)))
 789
 790 ;; ----------------------------------------------------------------------------
 791 (defun desktop-outvar (varspec)
 792   "Output a setq statement for variable VAR to the desktop file.
 793 The argument VARSPEC may be the variable name VAR (a symbol),
 794 or a cons cell of the form (VAR . MAX-SIZE),
 795 which means to truncate VAR's value to at most MAX-SIZE elements
 796 \(if the value is a list) before saving the value."
 797   (let (var size)
 798     (if (consp varspec)
 799         (setq var (car varspec) size (cdr varspec))
 800       (setq var varspec))
 801     (when (boundp var)
 802       (when (and (integerp size)
 803                  (> size 0)
 804                  (listp (eval var)))
 805         (desktop-truncate (eval var) size))
 806       (insert "(setq "
 807               (symbol-name var)
 808               " "
 809               (desktop-value-to-string (symbol-value var))
 810               ")\n"))))
 811
 812 ;; ----------------------------------------------------------------------------
 813 (defun desktop-save-buffer-p (filename bufname mode &rest dummy)
 814   "Return t if buffer should have its state saved in the desktop file.
 815 FILENAME is the visited file name, BUFNAME is the buffer name, and
 816 MODE is the major mode.
 817 \n\(fn FILENAME BUFNAME MODE)"
 818   (let ((case-fold-search nil)
 819         dired-skip)
 820     (and (not (and (stringp desktop-buffers-not-to-save)
 821                    (not filename)
 822                    (string-match desktop-buffers-not-to-save bufname)))
 823          (not (memq mode desktop-modes-not-to-save))
 824          ;; FIXME this is broken if desktop-files-not-to-save is nil.
 825          (or (and filename
 826                   (stringp desktop-files-not-to-save)
 827                   (not (string-match desktop-files-not-to-save filename)))
 828              (and (eq mode 'dired-mode)
 829                   (with-current-buffer bufname
 830                     (not (setq dired-skip
 831                                (string-match desktop-files-not-to-save
 832                                              default-directory)))))
 833              (and (null filename)
 834                   (null dired-skip)     ; bug#5755
 835                   (with-current-buffer bufname desktop-save-buffer))))))
 836
 837 ;; ----------------------------------------------------------------------------
 838 (defun desktop-file-name (filename dirname)
 839   "Convert FILENAME to format specified in `desktop-file-name-format'.
 840 DIRNAME must be the directory in which the desktop file will be saved."
 841   (cond
 842     ((not filename) nil)
 843     ((eq desktop-file-name-format 'tilde)
 844      (let ((relative-name (file-relative-name (expand-file-name filename) "~")))
 845        (cond
 846          ((file-name-absolute-p relative-name) relative-name)
 847          ((string= "./" relative-name) "~/")
 848          ((string= "." relative-name) "~")
 849          (t (concat "~/" relative-name)))))
 850     ((eq desktop-file-name-format 'local) (file-relative-name filename dirname))
 851     (t (expand-file-name filename))))
 852
 853
 854 ;; ----------------------------------------------------------------------------
 855 ;;;###autoload
 856 (defun desktop-save (dirname &optional release)
 857   "Save the desktop in a desktop file.
 858 Parameter DIRNAME specifies where to save the desktop file.
 859 Optional parameter RELEASE says whether we're done with this desktop.
 860 See also `desktop-base-file-name'."
 861   (interactive "DDirectory to save desktop file in: ")
 862   (setq desktop-dirname (file-name-as-directory (expand-file-name dirname)))
 863   (save-excursion
 864     (let ((eager desktop-restore-eager)
 865           (new-modtime (nth 5 (file-attributes (desktop-full-file-name)))))
 866       (when
 867           (or (not new-modtime)         ; nothing to overwrite
 868               (equal desktop-file-modtime new-modtime)
 869               (yes-or-no-p (if desktop-file-modtime
 870                                (if (> (float-time new-modtime) (float-time desktop-file-modtime))
 871                                    "Desktop file is more recent than the one loaded.  Save anyway? "
 872                                  "Desktop file isn't the one loaded.  Overwrite it? ")
 873                              "Current desktop was not loaded from a file.  Overwrite this desktop file? "))
 874               (unless release (error "Desktop file conflict")))
 875
 876         ;; If we're done with it, release the lock.
 877         ;; Otherwise, claim it if it's unclaimed or if we created it.
 878         (if release
 879             (desktop-release-lock)
 880           (unless (and new-modtime (desktop-owner)) (desktop-claim-lock)))
 881
 882         (with-temp-buffer
 883           (insert
 884            ";; -*- mode: emacs-lisp; coding: emacs-mule; -*-\n"
 885            desktop-header
 886            ";; Created " (current-time-string) "\n"
 887            ";; Desktop file format version " desktop-file-version "\n"
 888            ";; Emacs version " emacs-version "\n")
 889           (save-excursion (run-hooks 'desktop-save-hook))
 890           (goto-char (point-max))
 891           (insert "\n;; Global section:\n")
 892           (mapc (function desktop-outvar) desktop-globals-to-save)
 893           (when (memq 'kill-ring desktop-globals-to-save)
 894             (insert
 895              "(setq kill-ring-yank-pointer (nthcdr "
 896              (int-to-string (- (length kill-ring) (length kill-ring-yank-pointer)))
 897              " kill-ring))\n"))
 898
 899           (insert "\n;; Buffer section -- buffers listed in same order as in buffer list:\n")
 900           (dolist (l (mapcar 'desktop-buffer-info (buffer-list)))
 901             (let ((base (pop l)))
 902               (when (apply 'desktop-save-buffer-p l)
 903                 (insert "("
 904                         (if (or (not (integerp eager))
 905                                 (if (zerop eager)
 906                                     nil
 907                                   (setq eager (1- eager))))
 908                             "desktop-create-buffer"
 909                           "desktop-append-buffer-args")
 910                         " "
 911                         desktop-file-version)
 912                 ;; If there's a non-empty base name, we save it instead of the buffer name
 913                 (when (and base (not (string= base "")))
 914                   (setcar (nthcdr 1 l) base))
 915                 (dolist (e l)
 916                   (insert "\n  " (desktop-value-to-string e)))
 917                 (insert ")\n\n"))))
 918
 919           (setq default-directory desktop-dirname)
 920           (let ((coding-system-for-write 'emacs-mule))
 921             (write-region (point-min) (point-max) (desktop-full-file-name) nil 'nomessage))
 922           ;; We remember when it was modified (which is presumably just now).
 923           (setq desktop-file-modtime (nth 5 (file-attributes (desktop-full-file-name)))))))))
 924
 925 ;; ----------------------------------------------------------------------------
 926 ;;;###autoload
 927 (defun desktop-remove ()
 928   "Delete desktop file in `desktop-dirname'.
 929 This function also sets `desktop-dirname' to nil."
 930   (interactive)
 931   (when desktop-dirname
 932     (let ((filename (desktop-full-file-name)))
 933       (setq desktop-dirname nil)
 934       (when (file-exists-p filename)
 935         (delete-file filename)))))
 936
 937 (defvar desktop-buffer-args-list nil
 938   "List of args for `desktop-create-buffer'.")
 939
 940 (defvar desktop-lazy-timer nil)
 941
 942 ;; ----------------------------------------------------------------------------
 943 ;;;###autoload
 944 (defun desktop-read (&optional dirname)
 945   "Read and process the desktop file in directory DIRNAME.
 946 Look for a desktop file in DIRNAME, or if DIRNAME is omitted, look in
 947 directories listed in `desktop-path'.  If a desktop file is found, it
 948 is processed and `desktop-after-read-hook' is run.  If no desktop file
 949 is found, clear the desktop and run `desktop-no-desktop-file-hook'.
 950 This function is a no-op when Emacs is running in batch mode.
 951 It returns t if a desktop file was loaded, nil otherwise."
 952   (interactive)
 953   (unless noninteractive
 954     (setq desktop-dirname
 955           (file-name-as-directory
 956            (expand-file-name
 957             (or
 958              ;; If DIRNAME is specified, use it.
 959              (and (< 0 (length dirname)) dirname)
 960              ;; Otherwise search desktop file in desktop-path.
 961              (let ((dirs desktop-path))
 962                (while (and dirs
 963                            (not (file-exists-p
 964                                  (desktop-full-file-name (car dirs)))))
 965                  (setq dirs (cdr dirs)))
 966                (and dirs (car dirs)))
 967              ;; If not found and `desktop-path' is non-nil, use its first element.
 968              (and desktop-path (car desktop-path))
 969              ;; Default: Home directory.
 970              "~"))))
 971     (if (file-exists-p (desktop-full-file-name))
 972         ;; Desktop file found, but is it already in use?
 973         (let ((desktop-first-buffer nil)
 974               (desktop-buffer-ok-count 0)
 975               (desktop-buffer-fail-count 0)
 976               (owner (desktop-owner))
 977               ;; Avoid desktop saving during evaluation of desktop buffer.
 978               (desktop-save nil))
 979           (if (and owner
 980                    (memq desktop-load-locked-desktop '(nil ask))
 981                    (or (null desktop-load-locked-desktop)
 982                        (not (y-or-n-p (format "Warning: desktop file appears to be in use by PID %s.\n\
 983 Using it may cause conflicts.  Use it anyway? " owner)))))
 984               (let ((default-directory desktop-dirname))
 985                 (setq desktop-dirname nil)
 986                 (run-hooks 'desktop-not-loaded-hook)
 987                 (unless desktop-dirname
 988                   (message "Desktop file in use; not loaded.")))
 989             (desktop-lazy-abort)
 990             ;; Evaluate desktop buffer and remember when it was modified.
 991             (load (desktop-full-file-name) t t t)
 992             (setq desktop-file-modtime (nth 5 (file-attributes (desktop-full-file-name))))
 993             ;; If it wasn't already, mark it as in-use, to bother other
 994             ;; desktop instances.
 995             (unless owner
 996               (condition-case nil
 997                   (desktop-claim-lock)
 998                 (file-error (message "Couldn't record use of desktop file")
 999                             (sit-for 1))))
1000
1001             ;; `desktop-create-buffer' puts buffers at end of the buffer list.
1002             ;; We want buffers existing prior to evaluating the desktop (and
1003             ;; not reused) to be placed at the end of the buffer list, so we
1004             ;; move them here.
1005             (mapc 'bury-buffer
1006                   (nreverse (cdr (memq desktop-first-buffer (nreverse (buffer-list))))))
1007             (switch-to-buffer (car (buffer-list)))
1008             (run-hooks 'desktop-delay-hook)
1009             (setq desktop-delay-hook nil)
1010             (run-hooks 'desktop-after-read-hook)
1011             (message "Desktop: %d buffer%s restored%s%s."
1012                      desktop-buffer-ok-count
1013                      (if (= 1 desktop-buffer-ok-count) "" "s")
1014                      (if (< 0 desktop-buffer-fail-count)
1015                          (format ", %d failed to restore" desktop-buffer-fail-count)
1016                        "")
1017                      (if desktop-buffer-args-list
1018                          (format ", %d to restore lazily"
1019                                  (length desktop-buffer-args-list))
1020                        ""))
1021             t))
1022       ;; No desktop file found.
1023       (desktop-clear)
1024       (let ((default-directory desktop-dirname))
1025         (run-hooks 'desktop-no-desktop-file-hook))
1026       (message "No desktop file.")
1027       nil)))
1028
1029 ;; ----------------------------------------------------------------------------
1030 ;; Maintained for backward compatibility
1031 ;;;###autoload
1032 (defun desktop-load-default ()
1033   "Load the `default' start-up library manually.
1034 Also inhibit further loading of it."
1035   (unless inhibit-default-init          ; safety check
1036     (load "default" t t)
1037     (setq inhibit-default-init t)))
1038 (make-obsolete 'desktop-load-default
1039                'desktop-save-mode "22.1")
1040
1041 ;; ----------------------------------------------------------------------------
1042 ;;;###autoload
1043 (defun desktop-change-dir (dirname)
1044   "Change to desktop saved in DIRNAME.
1045 Kill the desktop as specified by variables `desktop-save-mode' and
1046 `desktop-save', then clear the desktop and load the desktop file in
1047 directory DIRNAME."
1048   (interactive "DChange to directory: ")
1049   (setq dirname (file-name-as-directory (expand-file-name dirname desktop-dirname)))
1050   (desktop-kill)
1051   (desktop-clear)
1052   (desktop-read dirname))
1053
1054 ;; ----------------------------------------------------------------------------
1055 ;;;###autoload
1056 (defun desktop-save-in-desktop-dir ()
1057   "Save the desktop in directory `desktop-dirname'."
1058   (interactive)
1059   (if desktop-dirname
1060       (desktop-save desktop-dirname)
1061     (call-interactively 'desktop-save))
1062   (message "Desktop saved in %s" (abbreviate-file-name desktop-dirname)))
1063
1064 ;; ----------------------------------------------------------------------------
1065 ;;;###autoload
1066 (defun desktop-revert ()
1067   "Revert to the last loaded desktop."
1068   (interactive)
1069   (unless desktop-dirname
1070     (error "Unknown desktop directory"))
1071   (unless (file-exists-p (desktop-full-file-name))
1072     (error "No desktop file found"))
1073   (desktop-clear)
1074   (desktop-read desktop-dirname))
1075
1076 (defvar desktop-buffer-major-mode)
1077 (defvar desktop-buffer-locals)
1078 ;; ----------------------------------------------------------------------------
1079 (defun desktop-restore-file-buffer (desktop-buffer-file-name
1080                                     desktop-buffer-name
1081                                     desktop-buffer-misc)
1082   "Restore a file buffer."
1083   (when desktop-buffer-file-name
1084     (if (or (file-exists-p desktop-buffer-file-name)
1085             (let ((msg (format "Desktop: File \"%s\" no longer exists."
1086                                desktop-buffer-file-name)))
1087               (if desktop-missing-file-warning
1088                   (y-or-n-p (concat msg " Re-create buffer? "))
1089                 (message "%s" msg)
1090                 nil)))
1091         (let* ((auto-insert nil) ; Disable auto insertion
1092                (coding-system-for-read
1093                 (or coding-system-for-read
1094                     (cdr (assq 'buffer-file-coding-system
1095                                desktop-buffer-locals))))
1096                (buf (find-file-noselect desktop-buffer-file-name)))
1097           (condition-case nil
1098               (switch-to-buffer buf)
1099             (error (pop-to-buffer buf)))
1100           (and (not (eq major-mode desktop-buffer-major-mode))
1101                (functionp desktop-buffer-major-mode)
1102                (funcall desktop-buffer-major-mode))
1103           buf)
1104       nil)))
1105
1106 (defun desktop-load-file (function)
1107   "Load the file where auto loaded FUNCTION is defined."
1108   (when function
1109     (let ((fcell (and (fboundp function) (symbol-function function))))
1110       (when (and (listp fcell)
1111                  (eq 'autoload (car fcell)))
1112         (load (cadr fcell))))))
1113
1114 ;; ----------------------------------------------------------------------------
1115 ;; Create a buffer, load its file, set its mode, ...;
1116 ;; called from Desktop file only.
1117
1118 ;; Just to silence the byte compiler.
1119
1120 (defvar desktop-first-buffer)          ; Dynamically bound in `desktop-read'
1121
1122 ;; Bound locally in `desktop-read'.
1123 (defvar desktop-buffer-ok-count)
1124 (defvar desktop-buffer-fail-count)
1125
1126 (defun desktop-create-buffer
1127   (desktop-file-version
1128    desktop-buffer-file-name
1129    desktop-buffer-name
1130    desktop-buffer-major-mode
1131    desktop-buffer-minor-modes
1132    desktop-buffer-point
1133    desktop-buffer-mark
1134    desktop-buffer-read-only
1135    desktop-buffer-misc
1136    &optional
1137    desktop-buffer-locals)
1138   ;; To make desktop files with relative file names possible, we cannot
1139   ;; allow `default-directory' to change. Therefore we save current buffer.
1140   (save-current-buffer
1141     ;; Give major mode module a chance to add a handler.
1142     (desktop-load-file desktop-buffer-major-mode)
1143     (let ((buffer-list (buffer-list))
1144           (result
1145            (condition-case-no-debug err
1146                (funcall (or (cdr (assq desktop-buffer-major-mode
1147                                        desktop-buffer-mode-handlers))
1148                             'desktop-restore-file-buffer)
1149                         desktop-buffer-file-name
1150                         desktop-buffer-name
1151                         desktop-buffer-misc)
1152              (error
1153               (message "Desktop: Can't load buffer %s: %s"
1154                        desktop-buffer-name
1155                        (error-message-string err))
1156               (when desktop-missing-file-warning (sit-for 1))
1157               nil))))
1158       (if (bufferp result)
1159           (setq desktop-buffer-ok-count (1+ desktop-buffer-ok-count))
1160         (setq desktop-buffer-fail-count (1+ desktop-buffer-fail-count))
1161         (setq result nil))
1162       ;; Restore buffer list order with new buffer at end. Don't change
1163       ;; the order for old desktop files (old desktop module behaviour).
1164       (unless (< desktop-file-version 206)
1165         (mapc 'bury-buffer buffer-list)
1166         (when result (bury-buffer result)))
1167       (when result
1168         (unless (or desktop-first-buffer (< desktop-file-version 206))
1169           (setq desktop-first-buffer result))
1170         (set-buffer result)
1171         (unless (equal (buffer-name) desktop-buffer-name)
1172           (rename-buffer desktop-buffer-name t))
1173         ;; minor modes
1174         (cond ((equal '(t) desktop-buffer-minor-modes) ; backwards compatible
1175                (auto-fill-mode 1))
1176               ((equal '(nil) desktop-buffer-minor-modes) ; backwards compatible
1177                (auto-fill-mode 0))
1178               (t
1179                (dolist (minor-mode desktop-buffer-minor-modes)
1180                  ;; Give minor mode module a chance to add a handler.
1181                  (desktop-load-file minor-mode)
1182                  (let ((handler (cdr (assq minor-mode desktop-minor-mode-handlers))))
1183                    (if handler
1184                        (funcall handler desktop-buffer-locals)
1185                      (when (functionp minor-mode)
1186                        (funcall minor-mode 1)))))))
1187         ;; Even though point and mark are non-nil when written by
1188         ;; `desktop-save', they may be modified by handlers wanting to set
1189         ;; point or mark themselves.
1190         (when desktop-buffer-point
1191           (goto-char
1192             (condition-case err
1193                 ;; Evaluate point.  Thus point can be something like
1194                 ;; '(search-forward ...
1195                 (eval desktop-buffer-point)
1196               (error (message "%s" (error-message-string err)) 1))))
1197         (when desktop-buffer-mark
1198           (if (consp desktop-buffer-mark)
1199               (progn
1200                 (set-mark (car desktop-buffer-mark))
1201                 (setq mark-active (car (cdr desktop-buffer-mark))))
1202             (set-mark desktop-buffer-mark)))
1203         ;; Never override file system if the file really is read-only marked.
1204         (when desktop-buffer-read-only (setq buffer-read-only desktop-buffer-read-only))
1205         (while desktop-buffer-locals
1206           (let ((this (car desktop-buffer-locals)))
1207             (if (consp this)
1208                 ;; an entry of this form `(symbol . value)'
1209                 (progn
1210                   (make-local-variable (car this))
1211                   (set (car this) (cdr this)))
1212               ;; an entry of the form `symbol'
1213               (make-local-variable this)
1214               (makunbound this)))
1215           (setq desktop-buffer-locals (cdr desktop-buffer-locals)))))))
1216
1217 ;; ----------------------------------------------------------------------------
1218 ;; Backward compatibility -- update parameters to 205 standards.
1219 (defun desktop-buffer (desktop-buffer-file-name desktop-buffer-name
1220                        desktop-buffer-major-mode
1221                        mim pt mk ro tl fc cfs cr desktop-buffer-misc)
1222   (desktop-create-buffer 205 desktop-buffer-file-name desktop-buffer-name
1223                          desktop-buffer-major-mode (cdr mim) pt mk ro
1224                          desktop-buffer-misc
1225                          (list (cons 'truncate-lines tl)
1226                                (cons 'fill-column fc)
1227                                (cons 'case-fold-search cfs)
1228                                (cons 'case-replace cr)
1229                                (cons 'overwrite-mode (car mim)))))
1230
1231 (defun desktop-append-buffer-args (&rest args)
1232   "Append ARGS at end of `desktop-buffer-args-list'.
1233 ARGS must be an argument list for `desktop-create-buffer'."
1234   (setq desktop-buffer-args-list (nconc desktop-buffer-args-list (list args)))
1235   (unless desktop-lazy-timer
1236     (setq desktop-lazy-timer
1237           (run-with-idle-timer desktop-lazy-idle-delay t 'desktop-idle-create-buffers))))
1238
1239 (defun desktop-lazy-create-buffer ()
1240   "Pop args from `desktop-buffer-args-list', create buffer and bury it."
1241   (when desktop-buffer-args-list
1242     (let* ((remaining (length desktop-buffer-args-list))
1243            (args (pop desktop-buffer-args-list))
1244            (buffer-name (nth 2 args))
1245            (msg (format "Desktop lazily opening %s (%s remaining)..."
1246                             buffer-name remaining)))
1247       (when desktop-lazy-verbose
1248         (message "%s" msg))
1249       (let ((desktop-first-buffer nil)
1250             (desktop-buffer-ok-count 0)
1251             (desktop-buffer-fail-count 0))
1252         (apply 'desktop-create-buffer args)
1253         (run-hooks 'desktop-delay-hook)
1254         (setq desktop-delay-hook nil)
1255         (bury-buffer (get-buffer buffer-name))
1256         (when desktop-lazy-verbose
1257           (message "%s%s" msg (if (> desktop-buffer-ok-count 0) "done" "failed")))))))
1258
1259 (defun desktop-idle-create-buffers ()
1260   "Create buffers until the user does something, then stop.
1261 If there are no buffers left to create, kill the timer."
1262   (let ((repeat 1))
1263     (while (and repeat desktop-buffer-args-list)
1264       (save-window-excursion
1265         (desktop-lazy-create-buffer))
1266       (setq repeat (sit-for 0.2))
1267     (unless desktop-buffer-args-list
1268       (cancel-timer desktop-lazy-timer)
1269       (setq desktop-lazy-timer nil)
1270       (message "Lazy desktop load complete")
1271       (sit-for 3)
1272       (message "")))))
1273
1274 (defun desktop-lazy-complete ()
1275   "Run the desktop load to completion."
1276   (interactive)
1277   (let ((desktop-lazy-verbose t))
1278     (while desktop-buffer-args-list
1279       (save-window-excursion
1280         (desktop-lazy-create-buffer)))
1281     (message "Lazy desktop load complete")))
1282
1283 (defun desktop-lazy-abort ()
1284   "Abort lazy loading of the desktop."
1285   (interactive)
1286   (when desktop-lazy-timer
1287     (cancel-timer desktop-lazy-timer)
1288     (setq desktop-lazy-timer nil))
1289   (when desktop-buffer-args-list
1290     (setq desktop-buffer-args-list nil)
1291     (when (called-interactively-p 'interactive)
1292       (message "Lazy desktop load aborted"))))
1293
1294 ;; ----------------------------------------------------------------------------
1295 ;; When `desktop-save-mode' is non-nil and "--no-desktop" is not specified on the
1296 ;; command line, we do the rest of what it takes to use desktop, but do it
1297 ;; after finishing loading the init file.
1298 ;; We cannot use `command-switch-alist' to process "--no-desktop" because these
1299 ;; functions are processed after `after-init-hook'.
1300 (add-hook
1301   'after-init-hook
1302   (lambda ()
1303     (let ((key "--no-desktop"))
1304       (when (member key command-line-args)
1305         (setq command-line-args (delete key command-line-args))
1306         (setq desktop-save-mode nil)))
1307     (when desktop-save-mode
1308       (desktop-read)
1309       (setq inhibit-startup-screen t))))
1310
1311 (provide 'desktop)
1312
1313 ;;; desktop.el ends here