lisp/desktop.el

   1 ;;; desktop.el --- save partial status of Emacs when killed
   2
   3 ;; Copyright (C) 1993-1995, 1997, 2000-2013 Free Software Foundation,
   4 ;; Inc.
   5
   6 ;; Author: Morten Welinder <terra@diku.dk>
   7 ;; Keywords: convenience
   8 ;; Favorite-brand-of-beer: None, I hate beer.
   9
  10 ;; This file is part of GNU Emacs.
  11
  12 ;; GNU Emacs is free software: you can redistribute it and/or modify
  13 ;; it under the terms of the GNU General Public License as published by
  14 ;; the Free Software Foundation, either version 3 of the License, or
  15 ;; (at your option) any later version.
  16
  17 ;; GNU Emacs is distributed in the hope that it will be useful,
  18 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  19 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20 ;; GNU General Public License for more details.
  21
  22 ;; You should have received a copy of the GNU General Public License
  23 ;; along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.
  24
  25 ;;; Commentary:
  26
  27 ;; Save the Desktop, i.e.,
  28 ;;      - some global variables
  29 ;;      - the list of buffers with associated files.  For each buffer also
  30 ;;              - the major mode
  31 ;;              - the default directory
  32 ;;              - the point
  33 ;;              - the mark & mark-active
  34 ;;              - buffer-read-only
  35 ;;              - some local variables
  36
  37 ;; To use this, use customize to turn on desktop-save-mode or add the
  38 ;; following line somewhere in your init file:
  39 ;;
  40 ;;      (desktop-save-mode 1)
  41 ;;
  42 ;; For further usage information, look at the section
  43 ;; (info "(emacs)Saving Emacs Sessions") in the GNU Emacs Manual.
  44
  45 ;; When the desktop module is loaded, the function `desktop-kill' is
  46 ;; added to the `kill-emacs-hook'.  This function is responsible for
  47 ;; saving the desktop when Emacs is killed.  Furthermore an anonymous
  48 ;; function is added to the `after-init-hook'.  This function is
  49 ;; responsible for loading the desktop when Emacs is started.
  50
  51 ;; Special handling.
  52 ;; -----------------
  53 ;; Variables `desktop-buffer-mode-handlers' and `desktop-minor-mode-handlers'
  54 ;; are supplied to handle special major and minor modes respectively.
  55 ;; `desktop-buffer-mode-handlers' is an alist of major mode specific functions
  56 ;; to restore a desktop buffer.  Elements must have the form
  57 ;;
  58 ;;    (MAJOR-MODE . RESTORE-BUFFER-FUNCTION).
  59 ;;
  60 ;; Functions listed are called by `desktop-create-buffer' when `desktop-read'
  61 ;; evaluates the desktop file.  Buffers with a major mode not specified here,
  62 ;; are restored by the default handler `desktop-restore-file-buffer'.
  63 ;; `desktop-minor-mode-handlers' is an alist of functions to restore
  64 ;; non-standard minor modes.  Elements must have the form
  65 ;;
  66 ;;    (MINOR-MODE . RESTORE-FUNCTION).
  67 ;;
  68 ;; Functions are called by `desktop-create-buffer' to restore minor modes.
  69 ;; Minor modes not specified here, are restored by the standard minor mode
  70 ;; function.  If you write a module that defines a major or minor mode that
  71 ;; needs a special handler, then place code like
  72
  73 ;;    (defun foo-restore-desktop-buffer
  74 ;;    ...
  75 ;;    (add-to-list 'desktop-buffer-mode-handlers
  76 ;;                 '(foo-mode . foo-restore-desktop-buffer))
  77
  78 ;; or
  79
  80 ;;    (defun bar-desktop-restore
  81 ;;    ...
  82 ;;    (add-to-list 'desktop-minor-mode-handlers
  83 ;;                 '(bar-mode . bar-desktop-restore))
  84
  85 ;; in the module itself, and make sure that the mode function is
  86 ;; autoloaded.  See the docstrings of `desktop-buffer-mode-handlers' and
  87 ;; `desktop-minor-mode-handlers' for more info.
  88
  89 ;; Minor modes.
  90 ;; ------------
  91 ;; Conventional minor modes (see node "Minor Mode Conventions" in the elisp
  92 ;; manual) are handled in the following way:
  93 ;; When `desktop-save' saves the state of a buffer to the desktop file, it
  94 ;; saves as `desktop-minor-modes' the list of names of those variables in
  95 ;; `minor-mode-alist' that have a non-nil value.
  96 ;; When `desktop-create' restores the buffer, each of the symbols in
  97 ;; `desktop-minor-modes' is called as function with parameter 1.
  98 ;; The variables `desktop-minor-mode-table' and `desktop-minor-mode-handlers'
  99 ;; are used to handle non-conventional minor modes.  `desktop-save' uses
 100 ;; `desktop-minor-mode-table' to map minor mode variables to minor mode
 101 ;; functions before writing `desktop-minor-modes'.  If a minor mode has a
 102 ;; variable name that is different form its function name, an entry
 103
 104 ;;    (NAME RESTORE-FUNCTION)
 105
 106 ;; should be added to `desktop-minor-mode-table'.  If a minor mode should not
 107 ;; be restored, RESTORE-FUNCTION should be set to nil.  `desktop-create' uses
 108 ;; `desktop-minor-mode-handlers' to lookup minor modes that needs a restore
 109 ;; function different from the usual minor mode function.
 110 ;; ---------------------------------------------------------------------------
 111
 112 ;; By the way: don't use desktop.el to customize Emacs -- the file .emacs
 113 ;; in your home directory is used for that.  Saving global default values
 114 ;; for buffers is an example of misuse.
 115
 116 ;; PLEASE NOTE: The kill ring can be saved as specified by the variable
 117 ;; `desktop-globals-to-save' (by default it isn't).  This may result in saving
 118 ;; things you did not mean to keep.  Use M-x desktop-clear RET.
 119
 120 ;; Thanks to  hetrick@phys.uva.nl (Jim Hetrick)      for useful ideas.
 121 ;;            avk@rtsg.mot.com (Andrew V. Klein)     for a dired tip.
 122 ;;            chris@tecc.co.uk (Chris Boucher)       for a mark tip.
 123 ;;            f89-kam@nada.kth.se (Klas Mellbourn)   for a mh-e tip.
 124 ;;            kifer@sbkifer.cs.sunysb.edu (M. Kifer) for a bug hunt.
 125 ;;            treese@lcs.mit.edu (Win Treese)        for ange-ftp tips.
 126 ;;            pot@cnuce.cnr.it (Francesco Potorti`)  for misc. tips.
 127 ;; ---------------------------------------------------------------------------
 128 ;; TODO:
 129 ;;
 130 ;; Save window configuration.
 131 ;; Recognize more minor modes.
 132 ;; Save mark rings.
 133
 134 ;;; Code:
 135
 136 (defvar desktop-file-version "206"
 137   "Version number of desktop file format.
 138 Written into the desktop file and used at desktop read to provide
 139 backward compatibility.")
 140
 141 ;; ----------------------------------------------------------------------------
 142 ;; USER OPTIONS -- settings you might want to play with.
 143 ;; ----------------------------------------------------------------------------
 144
 145 (defgroup desktop nil
 146   "Save status of Emacs when you exit."
 147   :group 'frames)
 148
 149 ;; Maintained for backward compatibility
 150 (define-obsolete-variable-alias 'desktop-enable 'desktop-save-mode "22.1")
 151 ;;;###autoload
 152 (define-minor-mode desktop-save-mode
 153   "Toggle desktop saving (Desktop Save mode).
 154 With a prefix argument ARG, enable Desktop Save mode if ARG is
 155 positive, and disable it otherwise.  If called from Lisp, enable
 156 the mode if ARG is omitted or nil.
 157
 158 If Desktop Save mode is enabled, the state of Emacs is saved from
 159 one session to another.  See variable `desktop-save' and function
 160 `desktop-read' for details."
 161   :global t
 162   :group 'desktop)
 163
 164 (defun desktop-save-mode-off ()
 165   "Disable `desktop-save-mode'.  Provided for use in hooks."
 166   (desktop-save-mode 0))
 167
 168 (defcustom desktop-save 'ask-if-new
 169   "Specifies whether the desktop should be saved when it is killed.
 170 A desktop is killed when the user changes desktop or quits Emacs.
 171 Possible values are:
 172    t             -- always save.
 173    ask           -- always ask.
 174    ask-if-new    -- ask if no desktop file exists, otherwise just save.
 175    ask-if-exists -- ask if desktop file exists, otherwise don't save.
 176    if-exists     -- save if desktop file exists, otherwise don't save.
 177    nil           -- never save.
 178 The desktop is never saved when `desktop-save-mode' is nil.
 179 The variables `desktop-dirname' and `desktop-base-file-name'
 180 determine where the desktop is saved."
 181   :type
 182   '(choice
 183     (const :tag "Always save" t)
 184     (const :tag "Always ask" ask)
 185     (const :tag "Ask if desktop file is new, else do save" ask-if-new)
 186     (const :tag "Ask if desktop file exists, else don't save" ask-if-exists)
 187     (const :tag "Save if desktop file exists, else don't" if-exists)
 188     (const :tag "Never save" nil))
 189   :group 'desktop
 190   :version "22.1")
 191
 192 (defcustom desktop-auto-save-timeout nil
 193   "Number of seconds between auto-saves of the desktop.
 194 Zero or nil means disable timer-based auto-saving."
 195   :type '(choice (const :tag "Off" nil)
 196                  (integer :tag "Seconds"))
 197   :set (lambda (symbol value)
 198          (set-default symbol value)
 199          (ignore-errors (desktop-auto-save-set-timer)))
 200   :group 'desktop
 201   :version "24.4")
 202
 203 (defcustom desktop-load-locked-desktop 'ask
 204   "Specifies whether the desktop should be loaded if locked.
 205 Possible values are:
 206    t    -- load anyway.
 207    nil  -- don't load.
 208    ask  -- ask the user.
 209 If the value is nil, or `ask' and the user chooses not to load the desktop,
 210 the normal hook `desktop-not-loaded-hook' is run."
 211   :type
 212   '(choice
 213     (const :tag "Load anyway" t)
 214     (const :tag "Don't load" nil)
 215     (const :tag "Ask the user" ask))
 216   :group 'desktop
 217   :version "22.2")
 218
 219 (define-obsolete-variable-alias 'desktop-basefilename
 220                                 'desktop-base-file-name "22.1")
 221
 222 (defcustom desktop-base-file-name
 223   (convert-standard-filename ".emacs.desktop")
 224   "Name of file for Emacs desktop, excluding the directory part."
 225   :type 'file
 226   :group 'desktop)
 227
 228 (defcustom desktop-base-lock-name
 229   (convert-standard-filename ".emacs.desktop.lock")
 230   "Name of lock file for Emacs desktop, excluding the directory part."
 231   :type 'file
 232   :group 'desktop
 233   :version "22.2")
 234
 235 (defcustom desktop-path (list user-emacs-directory "~")
 236   "List of directories to search for the desktop file.
 237 The base name of the file is specified in `desktop-base-file-name'."
 238   :type '(repeat directory)
 239   :group 'desktop
 240   :version "23.2")                      ; user-emacs-directory added
 241
 242 (defcustom desktop-missing-file-warning nil
 243   "If non-nil, offer to recreate the buffer of a deleted file.
 244 Also pause for a moment to display message about errors signaled in
 245 `desktop-buffer-mode-handlers'.
 246
 247 If nil, just print error messages in the message buffer."
 248   :type 'boolean
 249   :group 'desktop
 250   :version "22.1")
 251
 252 (defcustom desktop-no-desktop-file-hook nil
 253   "Normal hook run when `desktop-read' can't find a desktop file.
 254 Run in the directory in which the desktop file was sought.
 255 May be used to show a dired buffer."
 256   :type 'hook
 257   :group 'desktop
 258   :version "22.1")
 259
 260 (defcustom desktop-not-loaded-hook nil
 261   "Normal hook run when the user declines to re-use a desktop file.
 262 Run in the directory in which the desktop file was found.
 263 May be used to deal with accidental multiple Emacs jobs."
 264   :type 'hook
 265   :group 'desktop
 266   :options '(desktop-save-mode-off save-buffers-kill-emacs)
 267   :version "22.2")
 268
 269 (defcustom desktop-after-read-hook nil
 270   "Normal hook run after a successful `desktop-read'.
 271 May be used to show a buffer list."
 272   :type 'hook
 273   :group 'desktop
 274   :options '(list-buffers)
 275   :version "22.1")
 276
 277 (defcustom desktop-save-hook nil
 278   "Normal hook run before the desktop is saved in a desktop file.
 279 Run with the desktop buffer current with only the header present.
 280 May be used to add to the desktop code or to truncate history lists,
 281 for example."
 282   :type 'hook
 283   :group 'desktop)
 284
 285 (defcustom desktop-globals-to-save
 286   '(desktop-missing-file-warning
 287     tags-file-name
 288     tags-table-list
 289     search-ring
 290     regexp-search-ring
 291     register-alist
 292     file-name-history)
 293   "List of global variables saved by `desktop-save'.
 294 An element may be variable name (a symbol) or a cons cell of the form
 295 \(VAR . MAX-SIZE), which means to truncate VAR's value to at most
 296 MAX-SIZE elements (if the value is a list) before saving the value.
 297 Feature: Saving `kill-ring' implies saving `kill-ring-yank-pointer'."
 298   :type '(repeat (restricted-sexp :match-alternatives (symbolp consp)))
 299   :group 'desktop)
 300
 301 (defcustom desktop-globals-to-clear
 302   '(kill-ring
 303     kill-ring-yank-pointer
 304     search-ring
 305     search-ring-yank-pointer
 306     regexp-search-ring
 307     regexp-search-ring-yank-pointer)
 308   "List of global variables that `desktop-clear' will clear.
 309 An element may be variable name (a symbol) or a cons cell of the form
 310 \(VAR . FORM).  Symbols are set to nil and for cons cells VAR is set
 311 to the value obtained by evaluating FORM."
 312   :type '(repeat (restricted-sexp :match-alternatives (symbolp consp)))
 313   :group 'desktop
 314   :version "22.1")
 315
 316 (defcustom desktop-clear-preserve-buffers
 317   '("\\*scratch\\*" "\\*Messages\\*" "\\*server\\*" "\\*tramp/.+\\*"
 318     "\\*Warnings\\*")
 319   "List of buffers that `desktop-clear' should not delete.
 320 Each element is a regular expression.  Buffers with a name matched by any of
 321 these won't be deleted."
 322   :version "23.3"                       ; added Warnings - bug#6336
 323   :type '(repeat string)
 324   :group 'desktop)
 325
 326 ;;;###autoload
 327 (defcustom desktop-locals-to-save
 328   '(desktop-locals-to-save  ; Itself!  Think it over.
 329     truncate-lines
 330     case-fold-search
 331     case-replace
 332     fill-column
 333     overwrite-mode
 334     change-log-default-name
 335     line-number-mode
 336     column-number-mode
 337     size-indication-mode
 338     buffer-file-coding-system
 339     indent-tabs-mode
 340     tab-width
 341     indicate-buffer-boundaries
 342     indicate-empty-lines
 343     show-trailing-whitespace)
 344   "List of local variables to save for each buffer.
 345 The variables are saved only when they really are local.  Conventional minor
 346 modes are restored automatically; they should not be listed here."
 347   :type '(repeat symbol)
 348   :group 'desktop)
 349
 350 (defcustom desktop-buffers-not-to-save nil
 351   "Regexp identifying buffers that are to be excluded from saving."
 352   :type '(choice (const :tag "None" nil)
 353                  regexp)
 354   :version "23.2"                       ; set to nil
 355   :group 'desktop)
 356
 357 ;; Skip tramp and ange-ftp files
 358 (defcustom desktop-files-not-to-save
 359   "\\(^/[^/:]*:\\|(ftp)$\\)"
 360   "Regexp identifying files whose buffers are to be excluded from saving."
 361   :type '(choice (const :tag "None" nil)
 362                  regexp)
 363   :group 'desktop)
 364
 365 ;; We skip TAGS files to save time (tags-file-name is saved instead).
 366 (defcustom desktop-modes-not-to-save
 367   '(tags-table-mode)
 368   "List of major modes whose buffers should not be saved."
 369   :type '(repeat symbol)
 370   :group 'desktop)
 371
 372 (defcustom desktop-restore-frames nil
 373   "When non-nil, save window/frame configuration to desktop file."
 374   :type 'boolean
 375   :group 'desktop
 376   :version "24.4")
 377
 378 (defcustom desktop-restore-in-current-display nil
 379   "When non-nil, frames are restored in the current display.
 380 Otherwise they are restored, if possible, in their original displays."
 381   :type 'boolean
 382   :group 'desktop
 383   :version "24.4")
 384
 385 (defcustom desktop-file-name-format 'absolute
 386   "Format in which desktop file names should be saved.
 387 Possible values are:
 388    absolute -- Absolute file name.
 389    tilde    -- Relative to ~.
 390    local    -- Relative to directory of desktop file."
 391   :type '(choice (const absolute) (const tilde) (const local))
 392   :group 'desktop
 393   :version "22.1")
 394
 395 (defcustom desktop-restore-eager t
 396   "Number of buffers to restore immediately.
 397 Remaining buffers are restored lazily (when Emacs is idle).
 398 If value is t, all buffers are restored immediately."
 399   :type '(choice (const t) integer)
 400   :group 'desktop
 401   :version "22.1")
 402
 403 (defcustom desktop-lazy-verbose t
 404   "Verbose reporting of lazily created buffers."
 405   :type 'boolean
 406   :group 'desktop
 407   :version "22.1")
 408
 409 (defcustom desktop-lazy-idle-delay 5
 410   "Idle delay before starting to create buffers.
 411 See `desktop-restore-eager'."
 412   :type 'integer
 413   :group 'desktop
 414   :version "22.1")
 415
 416 ;;;###autoload
 417 (defvar-local desktop-save-buffer nil
 418   "When non-nil, save buffer status in desktop file.
 419
 420 If the value is a function, it is called by `desktop-save' with argument
 421 DESKTOP-DIRNAME to obtain auxiliary information to save in the desktop
 422 file along with the state of the buffer for which it was called.
 423
 424 When file names are returned, they should be formatted using the call
 425 \"(desktop-file-name FILE-NAME DESKTOP-DIRNAME)\".
 426
 427 Later, when `desktop-read' evaluates the desktop file, auxiliary information
 428 is passed as the argument DESKTOP-BUFFER-MISC to functions in
 429 `desktop-buffer-mode-handlers'.")
 430 (make-obsolete-variable 'desktop-buffer-modes-to-save
 431                         'desktop-save-buffer "22.1")
 432 (make-obsolete-variable 'desktop-buffer-misc-functions
 433                         'desktop-save-buffer "22.1")
 434
 435 ;;;###autoload
 436 (defvar desktop-buffer-mode-handlers nil
 437   "Alist of major mode specific functions to restore a desktop buffer.
 438 Functions listed are called by `desktop-create-buffer' when `desktop-read'
 439 evaluates the desktop file.  List elements must have the form
 440
 441    (MAJOR-MODE . RESTORE-BUFFER-FUNCTION).
 442
 443 Buffers with a major mode not specified here, are restored by the default
 444 handler `desktop-restore-file-buffer'.
 445
 446 Handlers are called with argument list
 447
 448    (DESKTOP-BUFFER-FILE-NAME DESKTOP-BUFFER-NAME DESKTOP-BUFFER-MISC)
 449
 450 Furthermore, they may use the following variables:
 451
 452    desktop-file-version
 453    desktop-buffer-major-mode
 454    desktop-buffer-minor-modes
 455    desktop-buffer-point
 456    desktop-buffer-mark
 457    desktop-buffer-read-only
 458    desktop-buffer-locals
 459
 460 If a handler returns a buffer, then the saved mode settings
 461 and variable values for that buffer are copied into it.
 462
 463 Modules that define a major mode that needs a special handler should contain
 464 code like
 465
 466    (defun foo-restore-desktop-buffer
 467    ...
 468    (add-to-list 'desktop-buffer-mode-handlers
 469                 '(foo-mode . foo-restore-desktop-buffer))
 470
 471 Furthermore the major mode function must be autoloaded.")
 472
 473 ;;;###autoload
 474 (put 'desktop-buffer-mode-handlers 'risky-local-variable t)
 475 (make-obsolete-variable 'desktop-buffer-handlers
 476                         'desktop-buffer-mode-handlers "22.1")
 477
 478 (defcustom desktop-minor-mode-table
 479   '((auto-fill-function auto-fill-mode)
 480     (vc-mode nil)
 481     (vc-dired-mode nil)
 482     (erc-track-minor-mode nil)
 483     (savehist-mode nil))
 484   "Table mapping minor mode variables to minor mode functions.
 485 Each entry has the form (NAME RESTORE-FUNCTION).
 486 NAME is the name of the buffer-local variable indicating that the minor
 487 mode is active.  RESTORE-FUNCTION is the function to activate the minor mode.
 488 RESTORE-FUNCTION nil means don't try to restore the minor mode.
 489 Only minor modes for which the name of the buffer-local variable
 490 and the name of the minor mode function are different have to be added to
 491 this table.  See also `desktop-minor-mode-handlers'."
 492   :type 'sexp
 493   :group 'desktop)
 494
 495 ;;;###autoload
 496 (defvar desktop-minor-mode-handlers nil
 497   "Alist of functions to restore non-standard minor modes.
 498 Functions are called by `desktop-create-buffer' to restore minor modes.
 499 List elements must have the form
 500
 501    (MINOR-MODE . RESTORE-FUNCTION).
 502
 503 Minor modes not specified here, are restored by the standard minor mode
 504 function.
 505
 506 Handlers are called with argument list
 507
 508    (DESKTOP-BUFFER-LOCALS)
 509
 510 Furthermore, they may use the following variables:
 511
 512    desktop-file-version
 513    desktop-buffer-file-name
 514    desktop-buffer-name
 515    desktop-buffer-major-mode
 516    desktop-buffer-minor-modes
 517    desktop-buffer-point
 518    desktop-buffer-mark
 519    desktop-buffer-read-only
 520    desktop-buffer-misc
 521
 522 When a handler is called, the buffer has been created and the major mode has
 523 been set, but local variables listed in desktop-buffer-locals has not yet been
 524 created and set.
 525
 526 Modules that define a minor mode that needs a special handler should contain
 527 code like
 528
 529    (defun foo-desktop-restore
 530    ...
 531    (add-to-list 'desktop-minor-mode-handlers
 532                 '(foo-mode . foo-desktop-restore))
 533
 534 Furthermore the minor mode function must be autoloaded.
 535
 536 See also `desktop-minor-mode-table'.")
 537
 538 ;;;###autoload
 539 (put 'desktop-minor-mode-handlers 'risky-local-variable t)
 540
 541 ;; ----------------------------------------------------------------------------
 542 (defvar desktop-dirname nil
 543   "The directory in which the desktop file should be saved.")
 544
 545 (defun desktop-full-file-name (&optional dirname)
 546   "Return the full name of the desktop file in DIRNAME.
 547 DIRNAME omitted or nil means use `desktop-dirname'."
 548   (expand-file-name desktop-base-file-name (or dirname desktop-dirname)))
 549
 550 (defun desktop-full-lock-name (&optional dirname)
 551   "Return the full name of the desktop lock file in DIRNAME.
 552 DIRNAME omitted or nil means use `desktop-dirname'."
 553   (expand-file-name desktop-base-lock-name (or dirname desktop-dirname)))
 554
 555 (defconst desktop-header
 556 ";; --------------------------------------------------------------------------
 557 ;; Desktop File for Emacs
 558 ;; --------------------------------------------------------------------------
 559 " "*Header to place in Desktop file.")
 560
 561 (defvar desktop-delay-hook nil
 562   "Hooks run after all buffers are loaded; intended for internal use.")
 563
 564 (defvar desktop-file-checksum nil
 565   "Checksum of the last auto-saved contents of the desktop file.
 566 Used to avoid writing contents unchanged between auto-saves.")
 567
 568 (defvar desktop--saved-states nil
 569   "Internal use only.")
 570
 571 ;; ----------------------------------------------------------------------------
 572 ;; Desktop file conflict detection
 573 (defvar desktop-file-modtime nil
 574   "When the desktop file was last modified to the knowledge of this Emacs.
 575 Used to detect desktop file conflicts.")
 576
 577 (defun desktop-owner (&optional dirname)
 578   "Return the PID of the Emacs process that owns the desktop file in DIRNAME.
 579 Return nil if no desktop file found or no Emacs process is using it.
 580 DIRNAME omitted or nil means use `desktop-dirname'."
 581   (let (owner
 582         (file (desktop-full-lock-name dirname)))
 583     (and (file-exists-p file)
 584          (ignore-errors
 585            (with-temp-buffer
 586              (insert-file-contents-literally file)
 587              (goto-char (point-min))
 588              (setq owner (read (current-buffer)))
 589              (integerp owner)))
 590          owner)))
 591
 592 (defun desktop-claim-lock (&optional dirname)
 593   "Record this Emacs process as the owner of the desktop file in DIRNAME.
 594 DIRNAME omitted or nil means use `desktop-dirname'."
 595   (write-region (number-to-string (emacs-pid)) nil
 596                 (desktop-full-lock-name dirname)))
 597
 598 (defun desktop-release-lock (&optional dirname)
 599   "Remove the lock file for the desktop in DIRNAME.
 600 DIRNAME omitted or nil means use `desktop-dirname'."
 601   (let ((file (desktop-full-lock-name dirname)))
 602     (when (file-exists-p file) (delete-file file))))
 603
 604 ;; ----------------------------------------------------------------------------
 605 (defun desktop-truncate (list n)
 606   "Truncate LIST to at most N elements destructively."
 607   (let ((here (nthcdr (1- n) list)))
 608     (when (consp here)
 609       (setcdr here nil))))
 610
 611 ;; ----------------------------------------------------------------------------
 612 ;;;###autoload
 613 (defun desktop-clear ()
 614   "Empty the Desktop.
 615 This kills all buffers except for internal ones and those with names matched by
 616 a regular expression in the list `desktop-clear-preserve-buffers'.
 617 Furthermore, it clears the variables listed in `desktop-globals-to-clear'."
 618   (interactive)
 619   (desktop-lazy-abort)
 620   (dolist (var desktop-globals-to-clear)
 621     (if (symbolp var)
 622         (eval `(setq-default ,var nil))
 623       (eval `(setq-default ,(car var) ,(cdr var)))))
 624   (let ((buffers (buffer-list))
 625         (preserve-regexp (concat "^\\("
 626                                  (mapconcat (lambda (regexp)
 627                                               (concat "\\(" regexp "\\)"))
 628                                             desktop-clear-preserve-buffers
 629                                             "\\|")
 630                                  "\\)$")))
 631     (while buffers
 632       (let ((bufname (buffer-name (car buffers))))
 633          (or
 634            (null bufname)
 635            (string-match-p preserve-regexp bufname)
 636            ;; Don't kill buffers made for internal purposes.
 637            (and (not (equal bufname "")) (eq (aref bufname 0) ?\s))
 638            (kill-buffer (car buffers))))
 639       (setq buffers (cdr buffers))))
 640   (delete-other-windows))
 641
 642 ;; ----------------------------------------------------------------------------
 643 (unless noninteractive
 644   (add-hook 'kill-emacs-hook 'desktop-kill))
 645
 646 (defun desktop-kill ()
 647   "If `desktop-save-mode' is non-nil, do what `desktop-save' says to do.
 648 If the desktop should be saved and `desktop-dirname'
 649 is nil, ask the user where to save the desktop."
 650   (when (and desktop-save-mode
 651              (let ((exists (file-exists-p (desktop-full-file-name))))
 652                (or (eq desktop-save t)
 653                    (and exists (eq desktop-save 'if-exists))
 654                    ;; If it exists, but we aren't using it, we are going
 655                    ;; to ask for a new directory below.
 656                    (and exists desktop-dirname (eq desktop-save 'ask-if-new))
 657                    (and
 658                     (or (memq desktop-save '(ask ask-if-new))
 659                         (and exists (eq desktop-save 'ask-if-exists)))
 660                     (y-or-n-p "Save desktop? ")))))
 661     (unless desktop-dirname
 662       (setq desktop-dirname
 663             (file-name-as-directory
 664              (expand-file-name
 665               (read-directory-name "Directory for desktop file: " nil nil t)))))
 666     (condition-case err
 667         (desktop-save desktop-dirname t)
 668       (file-error
 669        (unless (yes-or-no-p "Error while saving the desktop.  Ignore? ")
 670          (signal (car err) (cdr err))))))
 671   ;; If we own it, we don't anymore.
 672   (when (eq (emacs-pid) (desktop-owner)) (desktop-release-lock)))
 673
 674 ;; ----------------------------------------------------------------------------
 675 (defun desktop-list* (&rest args)
 676   (if (null (cdr args))
 677       (car args)
 678     (setq args (nreverse args))
 679     (let ((value (cons (nth 1 args) (car args))))
 680       (setq args (cdr (cdr args)))
 681       (while args
 682         (setq value (cons (car args) value))
 683         (setq args (cdr args)))
 684       value)))
 685
 686 ;; ----------------------------------------------------------------------------
 687 (defun desktop-buffer-info (buffer)
 688   (set-buffer buffer)
 689   (list
 690    ;; base name of the buffer; replaces the buffer name if managed by uniquify
 691    (and (fboundp 'uniquify-buffer-base-name) (uniquify-buffer-base-name))
 692    ;; basic information
 693    (desktop-file-name (buffer-file-name) desktop-dirname)
 694    (buffer-name)
 695    major-mode
 696    ;; minor modes
 697    (let (ret)
 698      (mapc
 699       #'(lambda (minor-mode)
 700           (and (boundp minor-mode)
 701                (symbol-value minor-mode)
 702                (let* ((special (assq minor-mode desktop-minor-mode-table))
 703                       (value (cond (special (cadr special))
 704                                    ((functionp minor-mode) minor-mode))))
 705                  (when value (add-to-list 'ret value)))))
 706       (mapcar #'car minor-mode-alist))
 707      ret)
 708    ;; point and mark, and read-only status
 709    (point)
 710    (list (mark t) mark-active)
 711    buffer-read-only
 712    ;; auxiliary information
 713    (when (functionp desktop-save-buffer)
 714      (funcall desktop-save-buffer desktop-dirname))
 715    ;; local variables
 716    (let ((locals desktop-locals-to-save)
 717          (loclist (buffer-local-variables))
 718          (ll))
 719      (while locals
 720        (let ((here (assq (car locals) loclist)))
 721          (if here
 722              (setq ll (cons here ll))
 723            (when (member (car locals) loclist)
 724              (setq ll (cons (car locals) ll)))))
 725        (setq locals (cdr locals)))
 726      ll)))
 727
 728 ;; ----------------------------------------------------------------------------
 729 (defun desktop--v2s (value)
 730   "Convert VALUE to a pair (QUOTE . SEXP); (eval SEXP) gives VALUE.
 731 SEXP is an sexp that when evaluated yields VALUE.
 732 QUOTE may be `may' (value may be quoted),
 733 `must' (value must be quoted), or nil (value must not be quoted)."
 734   (cond
 735     ((or (numberp value) (null value) (eq t value) (keywordp value))
 736      (cons 'may value))
 737     ((stringp value)
 738      (let ((copy (copy-sequence value)))
 739        (set-text-properties 0 (length copy) nil copy)
 740        ;; Get rid of text properties because we cannot read them.
 741        (cons 'may copy)))
 742     ((symbolp value)
 743      (cons 'must value))
 744     ((vectorp value)
 745      (let* ((pass1 (mapcar #'desktop--v2s value))
 746             (special (assq nil pass1)))
 747        (if special
 748            (cons nil `(vector
 749                        ,@(mapcar (lambda (el)
 750                                    (if (eq (car el) 'must)
 751                                        `',(cdr el) (cdr el)))
 752                                  pass1)))
 753          (cons 'may `[,@(mapcar #'cdr pass1)]))))
 754     ((consp value)
 755      (let ((p value)
 756            newlist
 757            use-list*)
 758        (while (consp p)
 759          (let ((q.sexp (desktop--v2s (car p))))
 760            (push q.sexp newlist))
 761          (setq p (cdr p)))
 762        (when p
 763          (let ((last (desktop--v2s p)))
 764            (setq use-list* t)
 765            (push last newlist)))
 766        (if (assq nil newlist)
 767            (cons nil
 768                  `(,(if use-list* 'desktop-list* 'list)
 769                    ,@(mapcar (lambda (el)
 770                                (if (eq (car el) 'must)
 771                                    `',(cdr el) (cdr el)))
 772                              (nreverse newlist))))
 773          (cons 'must
 774                `(,@(mapcar #'cdr
 775                            (nreverse (if use-list* (cdr newlist) newlist)))
 776                  ,@(if use-list* (cdar newlist)))))))
 777     ((subrp value)
 778      (cons nil `(symbol-function
 779                  ',(intern-soft (substring (prin1-to-string value) 7 -1)))))
 780     ((markerp value)
 781      (let ((pos (marker-position value))
 782            (buf (buffer-name (marker-buffer value))))
 783        (cons nil
 784              `(let ((mk (make-marker)))
 785                 (add-hook 'desktop-delay-hook
 786                           `(lambda ()
 787                              (set-marker ,mk ,,pos (get-buffer ,,buf))))
 788                 mk))))
 789     (t                                  ; Save as text.
 790      (cons 'may "Unprintable entity"))))
 791
 792 ;; ----------------------------------------------------------------------------
 793 (defun desktop-value-to-string (value)
 794   "Convert VALUE to a string that when read evaluates to the same value.
 795 Not all types of values are supported."
 796   (let* ((print-escape-newlines t)
 797          (float-output-format nil)
 798          (quote.sexp (desktop--v2s value))
 799          (quote (car quote.sexp))
 800          (txt
 801           (let ((print-quoted t))
 802             (prin1-to-string (cdr quote.sexp)))))
 803     (if (eq quote 'must)
 804         (concat "'" txt)
 805       txt)))
 806
 807 ;; ----------------------------------------------------------------------------
 808 (defun desktop-outvar (varspec)
 809   "Output a setq statement for variable VAR to the desktop file.
 810 The argument VARSPEC may be the variable name VAR (a symbol),
 811 or a cons cell of the form (VAR . MAX-SIZE),
 812 which means to truncate VAR's value to at most MAX-SIZE elements
 813 \(if the value is a list) before saving the value."
 814   (let (var size)
 815     (if (consp varspec)
 816         (setq var (car varspec) size (cdr varspec))
 817       (setq var varspec))
 818     (when (boundp var)
 819       (when (and (integerp size)
 820                  (> size 0)
 821                  (listp (eval var)))
 822         (desktop-truncate (eval var) size))
 823       (insert "(setq "
 824               (symbol-name var)
 825               " "
 826               (desktop-value-to-string (symbol-value var))
 827               ")\n"))))
 828
 829 ;; ----------------------------------------------------------------------------
 830 (defun desktop-save-buffer-p (filename bufname mode &rest _dummy)
 831   "Return t if buffer should have its state saved in the desktop file.
 832 FILENAME is the visited file name, BUFNAME is the buffer name, and
 833 MODE is the major mode.
 834 \n\(fn FILENAME BUFNAME MODE)"
 835   (let ((case-fold-search nil)
 836         dired-skip)
 837     (and (not (and (stringp desktop-buffers-not-to-save)
 838                    (not filename)
 839                    (string-match-p desktop-buffers-not-to-save bufname)))
 840          (not (memq mode desktop-modes-not-to-save))
 841          ;; FIXME this is broken if desktop-files-not-to-save is nil.
 842          (or (and filename
 843                   (stringp desktop-files-not-to-save)
 844                   (not (string-match-p desktop-files-not-to-save filename)))
 845              (and (memq mode '(dired-mode vc-dir-mode))
 846                   (with-current-buffer bufname
 847                     (not (setq dired-skip
 848                                (string-match-p desktop-files-not-to-save
 849                                                default-directory)))))
 850              (and (null filename)
 851                   (null dired-skip)     ; bug#5755
 852                   (with-current-buffer bufname desktop-save-buffer))))))
 853
 854 ;; ----------------------------------------------------------------------------
 855 (defun desktop-file-name (filename dirname)
 856   "Convert FILENAME to format specified in `desktop-file-name-format'.
 857 DIRNAME must be the directory in which the desktop file will be saved."
 858   (cond
 859     ((not filename) nil)
 860     ((eq desktop-file-name-format 'tilde)
 861      (let ((relative-name (file-relative-name (expand-file-name filename) "~")))
 862        (cond
 863          ((file-name-absolute-p relative-name) relative-name)
 864          ((string= "./" relative-name) "~/")
 865          ((string= "." relative-name) "~")
 866          (t (concat "~/" relative-name)))))
 867     ((eq desktop-file-name-format 'local) (file-relative-name filename dirname))
 868     (t (expand-file-name filename))))
 869
 870
 871 ;; ----------------------------------------------------------------------------
 872 (defconst desktop--excluded-frame-parameters
 873   '(buffer-list
 874     buffer-predicate
 875     buried-buffer-list
 876     explicit-name
 877     font
 878     font-backend
 879     minibuffer
 880     name
 881     outer-window-id
 882     parent-id
 883     window-id
 884     window-system)
 885   "Frame parameters not saved or restored.")
 886
 887 (defun desktop--filter-frame-parms (frame)
 888   "Return frame parameters of FRAME.
 889 Parameters in `desktop--excluded-frame-parameters' are excluded.
 890 Internal use only."
 891   (let (params)
 892     (dolist (param (frame-parameters frame))
 893       (unless (memq (car param) desktop--excluded-frame-parameters)
 894         (push param params)))
 895     params))
 896
 897 (defun desktop--save-frames ()
 898   "Save window/frame state, as a global variable.
 899 Intended to be called from `desktop-save'.
 900 Internal use only."
 901   (setq desktop--saved-states
 902         (and desktop-restore-frames
 903              (mapcar (lambda (frame)
 904                        (cons (desktop--filter-frame-parms frame)
 905                              (window-state-get (frame-root-window frame) t)))
 906                      (cons (selected-frame)
 907                            (delq (selected-frame) (frame-list))))))
 908   (desktop-outvar 'desktop--saved-states))
 909
 910 ;;;###autoload
 911 (defun desktop-save (dirname &optional release auto-save)
 912   "Save the desktop in a desktop file.
 913 Parameter DIRNAME specifies where to save the desktop file.
 914 Optional parameter RELEASE says whether we're done with this desktop.
 915 If AUTO-SAVE is non-nil, compare the saved contents to the one last saved,
 916 and don't save the buffer if they are the same."
 917   (interactive "DDirectory to save desktop file in: ")
 918   (setq desktop-dirname (file-name-as-directory (expand-file-name dirname)))
 919   (save-excursion
 920     (let ((eager desktop-restore-eager)
 921           (new-modtime (nth 5 (file-attributes (desktop-full-file-name)))))
 922       (when
 923           (or (not new-modtime)         ; nothing to overwrite
 924               (equal desktop-file-modtime new-modtime)
 925               (yes-or-no-p (if desktop-file-modtime
 926                                (if (> (float-time new-modtime) (float-time desktop-file-modtime))
 927                                    "Desktop file is more recent than the one loaded.  Save anyway? "
 928                                  "Desktop file isn't the one loaded.  Overwrite it? ")
 929                              "Current desktop was not loaded from a file.  Overwrite this desktop file? "))
 930               (unless release (error "Desktop file conflict")))
 931
 932         ;; If we're done with it, release the lock.
 933         ;; Otherwise, claim it if it's unclaimed or if we created it.
 934         (if release
 935             (desktop-release-lock)
 936           (unless (and new-modtime (desktop-owner)) (desktop-claim-lock)))
 937
 938         (with-temp-buffer
 939           (insert
 940            ";; -*- mode: emacs-lisp; coding: emacs-mule; -*-\n"
 941            desktop-header
 942            ";; Created " (current-time-string) "\n"
 943            ";; Desktop file format version " desktop-file-version "\n"
 944            ";; Emacs version " emacs-version "\n")
 945           (save-excursion (run-hooks 'desktop-save-hook))
 946           (goto-char (point-max))
 947           (insert "\n;; Global section:\n")
 948           ;; Called here because we save the window/frame state as a global
 949           ;; variable for compatibility with previous Emacsen.
 950           (desktop--save-frames)
 951           (mapc (function desktop-outvar) desktop-globals-to-save)
 952           (when (memq 'kill-ring desktop-globals-to-save)
 953             (insert
 954              "(setq kill-ring-yank-pointer (nthcdr "
 955              (int-to-string (- (length kill-ring) (length kill-ring-yank-pointer)))
 956              " kill-ring))\n"))
 957
 958           (insert "\n;; Buffer section -- buffers listed in same order as in buffer list:\n")
 959           (dolist (l (mapcar 'desktop-buffer-info (buffer-list)))
 960             (let ((base (pop l)))
 961               (when (apply 'desktop-save-buffer-p l)
 962                 (insert "("
 963                         (if (or (not (integerp eager))
 964                                 (if (zerop eager)
 965                                     nil
 966                                   (setq eager (1- eager))))
 967                             "desktop-create-buffer"
 968                           "desktop-append-buffer-args")
 969                         " "
 970                         desktop-file-version)
 971                 ;; If there's a non-empty base name, we save it instead of the buffer name
 972                 (when (and base (not (string= base "")))
 973                   (setcar (nthcdr 1 l) base))
 974                 (dolist (e l)
 975                   (insert "\n  " (desktop-value-to-string e)))
 976                 (insert ")\n\n"))))
 977
 978           (setq default-directory desktop-dirname)
 979           ;; If auto-saving, avoid writing if nothing has changed since the last write.
 980           ;; Don't check 300 characters of the header that contains the timestamp.
 981           (let ((checksum (and auto-save (md5 (current-buffer)
 982                                               (+ (point-min) 300) (point-max)
 983                                               'emacs-mule))))
 984             (unless (and auto-save (equal checksum desktop-file-checksum))
 985               (let ((coding-system-for-write 'emacs-mule))
 986                 (write-region (point-min) (point-max) (desktop-full-file-name) nil 'nomessage))
 987               (setq desktop-file-checksum checksum)
 988               ;; We remember when it was modified (which is presumably just now).
 989               (setq desktop-file-modtime (nth 5 (file-attributes (desktop-full-file-name)))))))))))
 990
 991 ;; ----------------------------------------------------------------------------
 992 ;;;###autoload
 993 (defun desktop-remove ()
 994   "Delete desktop file in `desktop-dirname'.
 995 This function also sets `desktop-dirname' to nil."
 996   (interactive)
 997   (when desktop-dirname
 998     (let ((filename (desktop-full-file-name)))
 999       (setq desktop-dirname nil)
1000       (when (file-exists-p filename)
1001         (delete-file filename)))))
1002
1003 (defvar desktop-buffer-args-list nil
1004   "List of args for `desktop-create-buffer'.")
1005
1006 (defvar desktop-lazy-timer nil)
1007
1008 ;; ----------------------------------------------------------------------------
1009 (defun desktop--restore-in-this-display-p ()
1010   (or desktop-restore-in-current-display
1011       (and (eq system-type 'windows-nt) (not (display-graphic-p)))))
1012
1013 (defun desktop--find-frame-in-display (frames display)
1014   (let (result)
1015     (while (and frames (not result))
1016       (if (equal display (frame-parameter (car frames) 'display))
1017           (setq result (car frames))
1018         (setq frames (cdr frames))))
1019     result))
1020
1021 (defun desktop--make-full-frame (full display config)
1022   (let ((width (and (eq full 'fullheight) (cdr (assq 'width config))))
1023         (height (and (eq full 'fullwidth) (cdr (assq 'height config))))
1024         (params '((visibility)))
1025         frame)
1026     (when width
1027       (setq params (append `((user-size . t) (width . ,width)) params)
1028             config (assq-delete-all 'height config)))
1029     (when height
1030       (setq params (append `((user-size . t) (height . ,height)) params)
1031             config (assq-delete-all 'width config)))
1032     (setq frame (make-frame-on-display display params))
1033     (modify-frame-parameters frame config)
1034     frame))
1035
1036 (defun desktop--restore-frames ()
1037   "Restore window/frame configuration.
1038 Internal use only."
1039   (when (and desktop-restore-frames desktop--saved-states)
1040     (let ((frames (frame-list))
1041           (current (frame-parameter nil 'display))
1042           (selected nil))
1043       (dolist (state desktop--saved-states)
1044         (condition-case err
1045             (let* ((config (car state))
1046                    (display (if (desktop--restore-in-this-display-p)
1047                                 (setcdr (assq 'display config) current)
1048                               (cdr (assq 'display config))))
1049                    (full (cdr (assq 'fullscreen config)))
1050                    (frame (and (not full)
1051                                (desktop--find-frame-in-display frames display))))
1052               (cond (full
1053                      ;; treat fullscreen/maximized frames specially
1054                      (setq frame (desktop--make-full-frame full display config)))
1055                     (frame
1056                      ;; found a frame in the right display -- reuse
1057                      (setq frames (delq frame frames))
1058                      (modify-frame-parameters frame config))
1059                     (t
1060                      ;; no frames in the display -- make a new one
1061                      (setq frame (make-frame-on-display display config))))
1062               ;; restore windows
1063               (window-state-put (cdr state) (frame-root-window frame) 'safe)
1064               (unless selected (setq selected frame)))
1065           (error
1066            (message "Error restoring frame: %S" (error-message-string err)))))
1067       (when selected
1068         ;; make sure the original selected frame is visible and selected
1069         (unless (or (frame-parameter selected 'visibility) (daemonp))
1070           (modify-frame-parameters selected '((visibility . t))))
1071         (select-frame-set-input-focus selected)
1072         ;; delete any remaining frames
1073         (mapc #'delete-frame frames)))))
1074
1075 ;;;###autoload
1076 (defun desktop-read (&optional dirname)
1077   "Read and process the desktop file in directory DIRNAME.
1078 Look for a desktop file in DIRNAME, or if DIRNAME is omitted, look in
1079 directories listed in `desktop-path'.  If a desktop file is found, it
1080 is processed and `desktop-after-read-hook' is run.  If no desktop file
1081 is found, clear the desktop and run `desktop-no-desktop-file-hook'.
1082 This function is a no-op when Emacs is running in batch mode.
1083 It returns t if a desktop file was loaded, nil otherwise."
1084   (interactive)
1085   (unless noninteractive
1086     (setq desktop-dirname
1087           (file-name-as-directory
1088            (expand-file-name
1089             (or
1090              ;; If DIRNAME is specified, use it.
1091              (and (< 0 (length dirname)) dirname)
1092              ;; Otherwise search desktop file in desktop-path.
1093              (let ((dirs desktop-path))
1094                (while (and dirs
1095                            (not (file-exists-p
1096                                  (desktop-full-file-name (car dirs)))))
1097                  (setq dirs (cdr dirs)))
1098                (and dirs (car dirs)))
1099              ;; If not found and `desktop-path' is non-nil, use its first element.
1100              (and desktop-path (car desktop-path))
1101              ;; Default: .emacs.d.
1102              user-emacs-directory))))
1103     (if (file-exists-p (desktop-full-file-name))
1104         ;; Desktop file found, but is it already in use?
1105         (let ((desktop-first-buffer nil)
1106               (desktop-buffer-ok-count 0)
1107               (desktop-buffer-fail-count 0)
1108               (owner (desktop-owner))
1109               ;; Avoid desktop saving during evaluation of desktop buffer.
1110               (desktop-save nil))
1111           (if (and owner
1112                    (memq desktop-load-locked-desktop '(nil ask))
1113                    (or (null desktop-load-locked-desktop)
1114                        (daemonp)
1115                        (not (y-or-n-p (format "Warning: desktop file appears to be in use by PID %s.\n\
1116 Using it may cause conflicts.  Use it anyway? " owner)))))
1117               (let ((default-directory desktop-dirname))
1118                 (setq desktop-dirname nil)
1119                 (run-hooks 'desktop-not-loaded-hook)
1120                 (unless desktop-dirname
1121                   (message "Desktop file in use; not loaded.")))
1122             (desktop-lazy-abort)
1123             ;; Evaluate desktop buffer and remember when it was modified.
1124             (load (desktop-full-file-name) t t t)
1125             (setq desktop-file-modtime (nth 5 (file-attributes (desktop-full-file-name))))
1126             ;; If it wasn't already, mark it as in-use, to bother other
1127             ;; desktop instances.
1128             (unless owner
1129               (condition-case nil
1130                   (desktop-claim-lock)
1131                 (file-error (message "Couldn't record use of desktop file")
1132                             (sit-for 1))))
1133
1134             ;; `desktop-create-buffer' puts buffers at end of the buffer list.
1135             ;; We want buffers existing prior to evaluating the desktop (and
1136             ;; not reused) to be placed at the end of the buffer list, so we
1137             ;; move them here.
1138             (mapc 'bury-buffer
1139                   (nreverse (cdr (memq desktop-first-buffer (nreverse (buffer-list))))))
1140             (switch-to-buffer (car (buffer-list)))
1141             (run-hooks 'desktop-delay-hook)
1142             (setq desktop-delay-hook nil)
1143             (desktop--restore-frames)
1144             (run-hooks 'desktop-after-read-hook)
1145             (message "Desktop: %d buffer%s restored%s%s."
1146                      desktop-buffer-ok-count
1147                      (if (= 1 desktop-buffer-ok-count) "" "s")
1148                      (if (< 0 desktop-buffer-fail-count)
1149                          (format ", %d failed to restore" desktop-buffer-fail-count)
1150                        "")
1151                      (if desktop-buffer-args-list
1152                          (format ", %d to restore lazily"
1153                                  (length desktop-buffer-args-list))
1154                        ""))
1155             ;; Bury the *Messages* buffer to not reshow it when burying
1156             ;; the buffer we switched to above.
1157             (when (buffer-live-p (get-buffer "*Messages*"))
1158               (bury-buffer "*Messages*"))
1159             ;; Clear all windows' previous and next buffers, these have
1160             ;; been corrupted by the `switch-to-buffer' calls in
1161             ;; `desktop-restore-file-buffer' (bug#11556).  This is a
1162             ;; brute force fix and should be replaced by a more subtle
1163             ;; strategy eventually.
1164             (walk-window-tree (lambda (window)
1165                                 (set-window-prev-buffers window nil)
1166                                 (set-window-next-buffers window nil)))
1167             t))
1168       ;; No desktop file found.
1169       (desktop-clear)
1170       (let ((default-directory desktop-dirname))
1171         (run-hooks 'desktop-no-desktop-file-hook))
1172       (message "No desktop file.")
1173       nil)))
1174
1175 ;; ----------------------------------------------------------------------------
1176 ;; Maintained for backward compatibility
1177 ;;;###autoload
1178 (defun desktop-load-default ()
1179   "Load the `default' start-up library manually.
1180 Also inhibit further loading of it."
1181   (declare (obsolete desktop-save-mode "22.1"))
1182   (unless inhibit-default-init          ; safety check
1183     (load "default" t t)
1184     (setq inhibit-default-init t)))
1185
1186 ;; ----------------------------------------------------------------------------
1187 ;;;###autoload
1188 (defun desktop-change-dir (dirname)
1189   "Change to desktop saved in DIRNAME.
1190 Kill the desktop as specified by variables `desktop-save-mode' and
1191 `desktop-save', then clear the desktop and load the desktop file in
1192 directory DIRNAME."
1193   (interactive "DChange to directory: ")
1194   (setq dirname (file-name-as-directory (expand-file-name dirname desktop-dirname)))
1195   (desktop-kill)
1196   (desktop-clear)
1197   (desktop-read dirname))
1198
1199 ;; ----------------------------------------------------------------------------
1200 ;;;###autoload
1201 (defun desktop-save-in-desktop-dir ()
1202   "Save the desktop in directory `desktop-dirname'."
1203   (interactive)
1204   (if desktop-dirname
1205       (desktop-save desktop-dirname)
1206     (call-interactively 'desktop-save))
1207   (message "Desktop saved in %s" (abbreviate-file-name desktop-dirname)))
1208
1209 ;; ----------------------------------------------------------------------------
1210 ;; Auto-Saving.
1211 (defvar desktop-auto-save-timer nil)
1212
1213 (defun desktop-auto-save ()
1214   "Save the desktop periodically.
1215 Called by the timer created in `desktop-auto-save-set-timer'."
1216   (when (and desktop-save-mode
1217              (integerp desktop-auto-save-timeout)
1218              (> desktop-auto-save-timeout 0)
1219              ;; Avoid desktop saving during lazy loading.
1220              (not desktop-lazy-timer)
1221              ;; Save only to own desktop file.
1222              (eq (emacs-pid) (desktop-owner))
1223              desktop-dirname)
1224     (desktop-save desktop-dirname nil t))
1225   (desktop-auto-save-set-timer))
1226
1227 (defun desktop-auto-save-set-timer ()
1228   "Reset the auto-save timer.
1229 Cancel any previous timer.  When `desktop-auto-save-timeout' is a positive
1230 integer, start a new timer to call `desktop-auto-save' in that many seconds."
1231   (when desktop-auto-save-timer
1232     (cancel-timer desktop-auto-save-timer)
1233     (setq desktop-auto-save-timer nil))
1234   (when (and (integerp desktop-auto-save-timeout)
1235              (> desktop-auto-save-timeout 0))
1236     (setq desktop-auto-save-timer
1237           (run-with-timer desktop-auto-save-timeout nil
1238                           'desktop-auto-save))))
1239
1240 ;; ----------------------------------------------------------------------------
1241 ;;;###autoload
1242 (defun desktop-revert ()
1243   "Revert to the last loaded desktop."
1244   (interactive)
1245   (unless desktop-dirname
1246     (error "Unknown desktop directory"))
1247   (unless (file-exists-p (desktop-full-file-name))
1248     (error "No desktop file found"))
1249   (desktop-clear)
1250   (desktop-read desktop-dirname))
1251
1252 (defvar desktop-buffer-major-mode)
1253 (defvar desktop-buffer-locals)
1254 (defvar auto-insert)  ; from autoinsert.el
1255 ;; ----------------------------------------------------------------------------
1256 (defun desktop-restore-file-buffer (buffer-filename
1257                                     _buffer-name
1258                                     _buffer-misc)
1259   "Restore a file buffer."
1260   (when buffer-filename
1261     (if (or (file-exists-p buffer-filename)
1262             (let ((msg (format "Desktop: File \"%s\" no longer exists."
1263                                buffer-filename)))
1264               (if desktop-missing-file-warning
1265                   (y-or-n-p (concat msg " Re-create buffer? "))
1266                 (message "%s" msg)
1267                 nil)))
1268         (let* ((auto-insert nil) ; Disable auto insertion
1269                (coding-system-for-read
1270                 (or coding-system-for-read
1271                     (cdr (assq 'buffer-file-coding-system
1272                                desktop-buffer-locals))))
1273                (buf (find-file-noselect buffer-filename)))
1274           (condition-case nil
1275               (switch-to-buffer buf)
1276             (error (pop-to-buffer buf)))
1277           (and (not (eq major-mode desktop-buffer-major-mode))
1278                (functionp desktop-buffer-major-mode)
1279                (funcall desktop-buffer-major-mode))
1280           buf)
1281       nil)))
1282
1283 (defun desktop-load-file (function)
1284   "Load the file where auto loaded FUNCTION is defined."
1285   (when (fboundp function)
1286     (autoload-do-load (symbol-function function) function)))
1287
1288 ;; ----------------------------------------------------------------------------
1289 ;; Create a buffer, load its file, set its mode, ...;
1290 ;; called from Desktop file only.
1291
1292 ;; Just to silence the byte compiler.
1293
1294 (defvar desktop-first-buffer)          ; Dynamically bound in `desktop-read'
1295
1296 ;; Bound locally in `desktop-read'.
1297 (defvar desktop-buffer-ok-count)
1298 (defvar desktop-buffer-fail-count)
1299
1300 (defun desktop-create-buffer
1301     (file-version
1302      buffer-filename
1303      buffer-name
1304      buffer-majormode
1305      buffer-minormodes
1306      buffer-point
1307      buffer-mark
1308      buffer-readonly
1309      buffer-misc
1310      &optional
1311      buffer-locals)
1312
1313   (let ((desktop-file-version       file-version)
1314         (desktop-buffer-file-name   buffer-filename)
1315         (desktop-buffer-name        buffer-name)
1316         (desktop-buffer-major-mode  buffer-majormode)
1317         (desktop-buffer-minor-modes buffer-minormodes)
1318         (desktop-buffer-point       buffer-point)
1319         (desktop-buffer-mark        buffer-mark)
1320         (desktop-buffer-read-only   buffer-readonly)
1321         (desktop-buffer-misc        buffer-misc)
1322         (desktop-buffer-locals      buffer-locals))
1323     ;; To make desktop files with relative file names possible, we cannot
1324     ;; allow `default-directory' to change. Therefore we save current buffer.
1325     (save-current-buffer
1326       ;; Give major mode module a chance to add a handler.
1327       (desktop-load-file desktop-buffer-major-mode)
1328       (let ((buffer-list (buffer-list))
1329             (result
1330              (condition-case-unless-debug err
1331                  (funcall (or (cdr (assq desktop-buffer-major-mode
1332                                          desktop-buffer-mode-handlers))
1333                               'desktop-restore-file-buffer)
1334                           desktop-buffer-file-name
1335                           desktop-buffer-name
1336                           desktop-buffer-misc)
1337                (error
1338                 (message "Desktop: Can't load buffer %s: %s"
1339                          desktop-buffer-name
1340                          (error-message-string err))
1341                 (when desktop-missing-file-warning (sit-for 1))
1342                 nil))))
1343         (if (bufferp result)
1344             (setq desktop-buffer-ok-count (1+ desktop-buffer-ok-count))
1345           (setq desktop-buffer-fail-count (1+ desktop-buffer-fail-count))
1346           (setq result nil))
1347         ;; Restore buffer list order with new buffer at end. Don't change
1348         ;; the order for old desktop files (old desktop module behavior).
1349         (unless (< desktop-file-version 206)
1350           (mapc 'bury-buffer buffer-list)
1351           (when result (bury-buffer result)))
1352         (when result
1353           (unless (or desktop-first-buffer (< desktop-file-version 206))
1354             (setq desktop-first-buffer result))
1355           (set-buffer result)
1356           (unless (equal (buffer-name) desktop-buffer-name)
1357             (rename-buffer desktop-buffer-name t))
1358           ;; minor modes
1359           (cond ((equal '(t) desktop-buffer-minor-modes) ; backwards compatible
1360                  (auto-fill-mode 1))
1361                 ((equal '(nil) desktop-buffer-minor-modes) ; backwards compatible
1362                  (auto-fill-mode 0))
1363                 (t
1364                  (dolist (minor-mode desktop-buffer-minor-modes)
1365                    ;; Give minor mode module a chance to add a handler.
1366                    (desktop-load-file minor-mode)
1367                    (let ((handler (cdr (assq minor-mode desktop-minor-mode-handlers))))
1368                      (if handler
1369                          (funcall handler desktop-buffer-locals)
1370                        (when (functionp minor-mode)
1371                          (funcall minor-mode 1)))))))
1372           ;; Even though point and mark are non-nil when written by
1373           ;; `desktop-save', they may be modified by handlers wanting to set
1374           ;; point or mark themselves.
1375           (when desktop-buffer-point
1376             (goto-char
1377              (condition-case err
1378                  ;; Evaluate point.  Thus point can be something like
1379                  ;; '(search-forward ...
1380                  (eval desktop-buffer-point)
1381                (error (message "%s" (error-message-string err)) 1))))
1382           (when desktop-buffer-mark
1383             (if (consp desktop-buffer-mark)
1384                 (progn
1385                   (set-mark (car desktop-buffer-mark))
1386                   (setq mark-active (car (cdr desktop-buffer-mark))))
1387               (set-mark desktop-buffer-mark)))
1388           ;; Never override file system if the file really is read-only marked.
1389           (when desktop-buffer-read-only (setq buffer-read-only desktop-buffer-read-only))
1390           (while desktop-buffer-locals
1391             (let ((this (car desktop-buffer-locals)))
1392               (if (consp this)
1393                   ;; an entry of this form `(symbol . value)'
1394                   (progn
1395                     (make-local-variable (car this))
1396                     (set (car this) (cdr this)))
1397                 ;; an entry of the form `symbol'
1398                 (make-local-variable this)
1399                 (makunbound this)))
1400             (setq desktop-buffer-locals (cdr desktop-buffer-locals))))))))
1401
1402 ;; ----------------------------------------------------------------------------
1403 ;; Backward compatibility -- update parameters to 205 standards.
1404 (defun desktop-buffer (buffer-filename buffer-name buffer-majormode
1405                        mim pt mk ro tl fc cfs cr buffer-misc)
1406   (desktop-create-buffer 205 buffer-filename buffer-name
1407                          buffer-majormode (cdr mim) pt mk ro
1408                          buffer-misc
1409                          (list (cons 'truncate-lines tl)
1410                                (cons 'fill-column fc)
1411                                (cons 'case-fold-search cfs)
1412                                (cons 'case-replace cr)
1413                                (cons 'overwrite-mode (car mim)))))
1414
1415 (defun desktop-append-buffer-args (&rest args)
1416   "Append ARGS at end of `desktop-buffer-args-list'.
1417 ARGS must be an argument list for `desktop-create-buffer'."
1418   (setq desktop-buffer-args-list (nconc desktop-buffer-args-list (list args)))
1419   (unless desktop-lazy-timer
1420     (setq desktop-lazy-timer
1421           (run-with-idle-timer desktop-lazy-idle-delay t 'desktop-idle-create-buffers))))
1422
1423 (defun desktop-lazy-create-buffer ()
1424   "Pop args from `desktop-buffer-args-list', create buffer and bury it."
1425   (when desktop-buffer-args-list
1426     (let* ((remaining (length desktop-buffer-args-list))
1427            (args (pop desktop-buffer-args-list))
1428            (buffer-name (nth 2 args))
1429            (msg (format "Desktop lazily opening %s (%s remaining)..."
1430                             buffer-name remaining)))
1431       (when desktop-lazy-verbose
1432         (message "%s" msg))
1433       (let ((desktop-first-buffer nil)
1434             (desktop-buffer-ok-count 0)
1435             (desktop-buffer-fail-count 0))
1436         (apply 'desktop-create-buffer args)
1437         (run-hooks 'desktop-delay-hook)
1438         (setq desktop-delay-hook nil)
1439         (bury-buffer (get-buffer buffer-name))
1440         (when desktop-lazy-verbose
1441           (message "%s%s" msg (if (> desktop-buffer-ok-count 0) "done" "failed")))))))
1442
1443 (defun desktop-idle-create-buffers ()
1444   "Create buffers until the user does something, then stop.
1445 If there are no buffers left to create, kill the timer."
1446   (let ((repeat 1))
1447     (while (and repeat desktop-buffer-args-list)
1448       (save-window-excursion
1449         (desktop-lazy-create-buffer))
1450       (setq repeat (sit-for 0.2))
1451     (unless desktop-buffer-args-list
1452       (cancel-timer desktop-lazy-timer)
1453       (setq desktop-lazy-timer nil)
1454       (message "Lazy desktop load complete")
1455       (sit-for 3)
1456       (message "")))))
1457
1458 (defun desktop-lazy-complete ()
1459   "Run the desktop load to completion."
1460   (interactive)
1461   (let ((desktop-lazy-verbose t))
1462     (while desktop-buffer-args-list
1463       (save-window-excursion
1464         (desktop-lazy-create-buffer)))
1465     (message "Lazy desktop load complete")))
1466
1467 (defun desktop-lazy-abort ()
1468   "Abort lazy loading of the desktop."
1469   (interactive)
1470   (when desktop-lazy-timer
1471     (cancel-timer desktop-lazy-timer)
1472     (setq desktop-lazy-timer nil))
1473   (when desktop-buffer-args-list
1474     (setq desktop-buffer-args-list nil)
1475     (when (called-interactively-p 'interactive)
1476       (message "Lazy desktop load aborted"))))
1477
1478 ;; ----------------------------------------------------------------------------
1479 ;; When `desktop-save-mode' is non-nil and "--no-desktop" is not specified on the
1480 ;; command line, we do the rest of what it takes to use desktop, but do it
1481 ;; after finishing loading the init file.
1482 ;; We cannot use `command-switch-alist' to process "--no-desktop" because these
1483 ;; functions are processed after `after-init-hook'.
1484 (add-hook
1485   'after-init-hook
1486   (lambda ()
1487     (let ((key "--no-desktop"))
1488       (when (member key command-line-args)
1489         (setq command-line-args (delete key command-line-args))
1490         (setq desktop-save-mode nil)))
1491     (when desktop-save-mode
1492       (desktop-read)
1493       (desktop-auto-save-set-timer)
1494       (setq inhibit-startup-screen t))))
1495
1496 ;; So we can restore vc-dir buffers.
1497 (autoload 'vc-dir-mode "vc-dir" nil t)
1498
1499 (provide 'desktop)
1500
1501 ;;; desktop.el ends here