Major bugfixes and slight enhancements.
[bpt/emacs.git] / lisp / server.el
1 ;;; server.el --- Lisp code for GNU Emacs running as server process
2
3 ;; Copyright (C) 1986,87,92,94,95,96,97,98,99,2000,01,02,2003
4 ;; Free Software Foundation, Inc.
5
6 ;; Author: William Sommerfeld <wesommer@athena.mit.edu>
7 ;; Maintainer: FSF
8 ;; Keywords: processes
9
10 ;; Changes by peck@sun.com and by rms.
11
12 ;; This file is part of GNU Emacs.
13
14 ;; GNU Emacs is free software; you can redistribute it and/or modify
15 ;; it under the terms of the GNU General Public License as published by
16 ;; the Free Software Foundation; either version 2, or (at your option)
17 ;; any later version.
18
19 ;; GNU Emacs is distributed in the hope that it will be useful,
20 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
21 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 ;; GNU General Public License for more details.
23
24 ;; You should have received a copy of the GNU General Public License
25 ;; along with GNU Emacs; see the file COPYING. If not, write to the
26 ;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
27 ;; Boston, MA 02111-1307, USA.
28
29 ;;; Commentary:
30
31 ;; This Lisp code is run in Emacs when it is to operate as
32 ;; a server for other processes.
33
34 ;; Load this library and do M-x server-edit to enable Emacs as a server.
35 ;; Emacs opens up a socket for communication with clients. If there are no
36 ;; client buffers to edit, server-edit acts like (switch-to-buffer
37 ;; (other-buffer))
38
39 ;; When some other program runs "the editor" to edit a file,
40 ;; "the editor" can be the Emacs client program ../lib-src/emacsclient.
41 ;; This program transmits the file names to Emacs through
42 ;; the server subprocess, and Emacs visits them and lets you edit them.
43
44 ;; Note that any number of clients may dispatch files to emacs to be edited.
45
46 ;; When you finish editing a Server buffer, again call server-edit
47 ;; to mark that buffer as done for the client and switch to the next
48 ;; Server buffer. When all the buffers for a client have been edited
49 ;; and exited with server-edit, the client "editor" will return
50 ;; to the program that invoked it.
51
52 ;; Your editing commands and Emacs's display output go to and from
53 ;; the terminal in the usual way. Thus, server operation is possible
54 ;; only when Emacs can talk to the terminal at the time you invoke
55 ;; the client. This is possible in four cases:
56
57 ;; 1. On a window system, where Emacs runs in one window and the
58 ;; program that wants to use "the editor" runs in another.
59
60 ;; 2. On a multi-terminal system, where Emacs runs on one terminal and the
61 ;; program that wants to use "the editor" runs on another.
62
63 ;; 3. When the program that wants to use "the editor" is running
64 ;; as a subprocess of Emacs.
65
66 ;; 4. On a system with job control, when Emacs is suspended, the program
67 ;; that wants to use "the editor" will stop and display
68 ;; "Waiting for Emacs...". It can then be suspended, and Emacs can be
69 ;; brought into the foreground for editing. When done editing, Emacs is
70 ;; suspended again, and the client program is brought into the foreground.
71
72 ;; The buffer local variable "server-buffer-clients" lists
73 ;; the clients who are waiting for this buffer to be edited.
74 ;; The global variable "server-clients" lists all the waiting clients,
75 ;; and which files are yet to be edited for each.
76
77 ;;; Code:
78
79 (eval-when-compile (require 'cl))
80
81 (defgroup server nil
82 "Emacs running as a server process."
83 :group 'external)
84
85 (defcustom server-visit-hook nil
86 "*Hook run when visiting a file for the Emacs server."
87 :group 'server
88 :type 'hook)
89
90 (defcustom server-switch-hook nil
91 "*Hook run when switching to a buffer for the Emacs server."
92 :group 'server
93 :type 'hook)
94
95 (defcustom server-done-hook nil
96 "*Hook run when done editing a buffer for the Emacs server."
97 :group 'server
98 :type 'hook)
99
100 (defvar server-process nil
101 "The current server process.")
102
103 (defvar server-clients nil
104 "List of current server clients.
105 Each element is (CLIENTID BUFFERS...) where CLIENTID is a string
106 that can be given to the server process to identify a client.
107 When a buffer is marked as \"done\", it is removed from this list.")
108
109 (defvar server-frames nil
110 "List of current server frames.
111 Each element is (CLIENTID FRAME) where CLIENTID is a string
112 that can be given to the server process to identify a client.
113 When all the buffers of the client are marked as \"done\",
114 the frame is deleted.")
115
116 (defvar server-buffer-clients nil
117 "List of client ids for clients requesting editing of current buffer.")
118 (make-variable-buffer-local 'server-buffer-clients)
119 ;; Changing major modes should not erase this local.
120 (put 'server-buffer-clients 'permanent-local t)
121
122 (defcustom server-window nil
123 "*Specification of the window to use for selecting Emacs server buffers.
124 If nil, use the selected window.
125 If it is a function, it should take one argument (a buffer) and
126 display and select it. A common value is `pop-to-buffer'.
127 If it is a window, use that.
128 If it is a frame, use the frame's selected window.
129
130 It is not meaningful to set this to a specific frame or window with Custom.
131 Only programs can do so."
132 :group 'server
133 :version "21.4"
134 :type '(choice (const :tag "Use selected window"
135 :match (lambda (widget value)
136 (not (functionp value)))
137 nil)
138 (function-item :tag "Use pop-to-buffer" pop-to-buffer)
139 (function :tag "Other function")))
140
141 (defcustom server-temp-file-regexp "^/tmp/Re\\|/draft$"
142 "*Regexp matching names of temporary files.
143 These are deleted and reused after each edit by the programs that
144 invoke the Emacs server."
145 :group 'server
146 :type 'regexp)
147
148 (defcustom server-kill-new-buffers t
149 "*Whether to kill buffers when done with them.
150 If non-nil, kill a buffer unless it already existed before editing
151 it with Emacs server. If nil, kill only buffers as specified by
152 `server-temp-file-regexp'.
153 Please note that only buffers are killed that still have a client,
154 i.e. buffers visited which \"emacsclient --no-wait\" are never killed in
155 this way."
156 :group 'server
157 :type 'boolean
158 :version "21.1")
159
160 (or (assq 'server-buffer-clients minor-mode-alist)
161 (setq minor-mode-alist (cons '(server-buffer-clients " Server") minor-mode-alist)))
162
163 (defvar server-existing-buffer nil
164 "Non-nil means the buffer existed before the server was asked to visit it.
165 This means that the server should not kill the buffer when you say you
166 are done with it in the server.")
167 (make-variable-buffer-local 'server-existing-buffer)
168
169 (defvar server-socket-name
170 (format "/tmp/emacs%d-%s/server" (user-uid)
171 (substring (system-name) 0 (string-match "\\." (system-name)))))
172
173 (defun server-log (string &optional client)
174 "If a *server* buffer exists, write STRING to it for logging purposes."
175 (if (get-buffer "*server*")
176 (with-current-buffer "*server*"
177 (goto-char (point-max))
178 (insert (current-time-string)
179 (if client (format " %s:" client) " ")
180 string)
181 (or (bolp) (newline)))))
182
183 (defun server-sentinel (proc msg)
184 (let ((client (assq proc server-clients)))
185 ;; Remove PROC from the list of clients.
186 (when client
187 (setq server-clients (delq client server-clients))
188 (let ((frame (assq (car client) server-frames)))
189 (setq server-frames (delq frame server-frames))
190 (when (frame-live-p (cadr frame)) (delete-frame (cadr frame) 'force)))
191 (dolist (buf (cdr client))
192 (with-current-buffer buf
193 ;; Remove PROC from the clients of each buffer.
194 (setq server-buffer-clients (delq proc server-buffer-clients))
195 ;; Kill the buffer if necessary.
196 (when (and (null server-buffer-clients)
197 (or (and server-kill-new-buffers
198 (not server-existing-buffer))
199 (server-temp-file-p)))
200 (kill-buffer (current-buffer)))))))
201 (server-log (format "Status changed to %s" (process-status proc)) proc))
202
203 (defun server-select-display (display)
204 ;; If the current frame is on `display' we're all set.
205 (unless (equal (frame-parameter (selected-frame) 'display) display)
206 ;; Otherwise, look for an existing frame there and select it.
207 (dolist (frame (frame-list))
208 (when (equal (frame-parameter frame 'display) display)
209 (select-frame frame)))
210 ;; If there's no frame on that display yet, create a dummy one
211 ;; and select it.
212 (unless (equal (frame-parameter (selected-frame) 'display) display)
213 (select-frame
214 (make-frame-on-display
215 display
216 ;; This frame is only there in place of an actual "current display"
217 ;; setting, so we want it to be as unobtrusive as possible. That's
218 ;; what the invisibility is for. The minibuffer setting is so that
219 ;; we don't end up displaying a buffer in it (which noone would
220 ;; notice).
221 '((visibility . nil) (minibuffer . only)))))))
222
223 (defun server-unquote-arg (arg)
224 (replace-regexp-in-string
225 "&." (lambda (s)
226 (case (aref s 1)
227 (?& "&")
228 (?- "-")
229 (?n "\n")
230 (t " ")))
231 arg t t))
232
233 (defun server-ensure-safe-dir (dir)
234 "Make sure DIR is a directory with no race-condition issues.
235 Creates the directory if necessary and makes sure:
236 - there's no symlink involved
237 - it's owned by us
238 - it's not readable/writable by anybody else."
239 (setq dir (directory-file-name dir))
240 (let ((attrs (file-attributes dir)))
241 (unless attrs
242 (letf (((default-file-modes) ?\700)) (make-directory dir))
243 (setq attrs (file-attributes dir)))
244 ;; Check that it's safe for use.
245 (unless (and (eq t (car attrs)) (eq (nth 2 attrs) (user-uid))
246 (zerop (logand ?\077 (file-modes dir))))
247 (error "The directory %s is unsafe" dir))))
248
249 ;;;###autoload
250 (defun server-start (&optional leave-dead)
251 "Allow this Emacs process to be a server for client processes.
252 This starts a server communications subprocess through which
253 client \"editors\" can send your editing commands to this Emacs job.
254 To use the server, set up the program `emacsclient' in the
255 Emacs distribution as your standard \"editor\".
256
257 Prefix arg means just kill any existing server communications subprocess."
258 (interactive "P")
259 ;; Make sure there is a safe directory in which to place the socket.
260 (server-ensure-safe-dir (file-name-directory server-socket-name))
261 ;; kill it dead!
262 (if server-process
263 (condition-case () (delete-process server-process) (error nil)))
264 ;; Delete the socket files made by previous server invocations.
265 (condition-case () (delete-file server-socket-name) (error nil))
266 ;; If this Emacs already had a server, clear out associated status.
267 (while server-clients
268 (let ((buffer (nth 1 (car server-clients))))
269 (server-buffer-done buffer)))
270 ;; Delete any remaining opened frames of the previous server.
271 (while server-frames
272 (let ((frame (cadar server-frames)))
273 (setq server-frames (cdr server-frames))
274 (when (frame-live-p frame) (delete-frame frame 'force))))
275 (unless leave-dead
276 (if server-process
277 (server-log (message "Restarting server")))
278 (letf (((default-file-modes) ?\700))
279 (setq server-process
280 (make-network-process
281 :name "server" :family 'local :server t :noquery t
282 :service server-socket-name
283 :sentinel 'server-sentinel :filter 'server-process-filter
284 ;; We must receive file names without being decoded.
285 ;; Those are decoded by server-process-filter according
286 ;; to file-name-coding-system.
287 :coding 'raw-text)))))
288
289 ;;;###autoload
290 (define-minor-mode server-mode
291 "Toggle Server mode.
292 With ARG, turn Server mode on if ARG is positive, off otherwise.
293 Server mode runs a process that accepts commands from the
294 `emacsclient' program. See `server-start' and Info node `Emacs server'."
295 :global t
296 :group 'server
297 :version "21.4"
298 ;; Fixme: Should this check for an existing server socket and do
299 ;; nothing if there is one (for multiple Emacs sessions)?
300 (server-start (not server-mode)))
301 \f
302 (defun server-process-filter (proc string)
303 "Process a request from the server to edit some files.
304 PROC is the server process. Format of STRING is \"PATH PATH PATH... \\n\"."
305 (server-log string proc)
306 (let ((prev (process-get proc 'previous-string)))
307 (when prev
308 (setq string (concat prev string))
309 (process-put proc 'previous-string nil)))
310 ;; If the input is multiple lines,
311 ;; process each line individually.
312 (while (string-match "\n" string)
313 (let ((request (substring string 0 (match-beginning 0)))
314 (coding-system (and default-enable-multibyte-characters
315 (or file-name-coding-system
316 default-file-name-coding-system)))
317 client nowait eval newframe
318 (files nil)
319 (lineno 1)
320 (columnno 0))
321 ;; Remove this line from STRING.
322 (setq string (substring string (match-end 0)))
323 (setq client (cons proc nil))
324 (while (string-match "[^ ]* " request)
325 (let ((arg (substring request (match-beginning 0) (1- (match-end 0)))))
326 (setq request (substring request (match-end 0)))
327 (cond
328 ((equal "-nowait" arg) (setq nowait t))
329 ((equal "-eval" arg) (setq eval t))
330 ((and (equal "-display" arg) (string-match "\\([^ ]*\\) " request))
331 (let ((display (server-unquote-arg (match-string 1 request))))
332 (setq request (substring request (match-end 0)))
333 (condition-case err
334 (server-select-display display)
335 (error (process-send-string proc (nth 1 err))
336 (setq request "")))))
337 ;; Open a new frame at the client. ARG is the name of the pseudo tty.
338 ((and (equal "-pty" arg) (string-match "\\([^ ]*\\) \\([^ ]*\\) " request))
339 (setq newframe t)
340 (let ((pty (server-unquote-arg (match-string 1 request)))
341 (type (server-unquote-arg (match-string 2 request))))
342 (setq request (substring request (match-end 0)))
343 (condition-case err
344 (let ((frame (make-terminal-frame `((tty . ,pty) (tty-type . ,type)))))
345 (setq server-frames (cons (list (car client) frame) server-frames))
346 (sit-for 0)
347 (process-send-string proc (concat (number-to-string (emacs-pid)) "\n"))
348 (select-frame frame))
349 (error (process-send-string proc (nth 1 err))
350 (setq request "")))))
351 ;; ARG is a line number option.
352 ((string-match "\\`\\+[0-9]+\\'" arg)
353 (setq lineno (string-to-int (substring arg 1))))
354 ;; ARG is line number:column option.
355 ((string-match "\\`+\\([0-9]+\\):\\([0-9]+\\)\\'" arg)
356 (setq lineno (string-to-int (match-string 1 arg))
357 columnno (string-to-int (match-string 2 arg))))
358 (t
359 ;; Undo the quoting that emacsclient does
360 ;; for certain special characters.
361 (setq arg (server-unquote-arg arg))
362 ;; Now decode the file name if necessary.
363 (if coding-system
364 (setq arg (decode-coding-string arg coding-system)))
365 (if eval
366 (condition-case err
367 (let ((v (eval (car (read-from-string arg)))))
368 (when (and (not newframe v))
369 (with-temp-buffer
370 (let ((standard-output (current-buffer)))
371 (pp v)
372 (process-send-region proc (point-min) (point-max))))))
373 (error (process-send-string proc (concat "*Error* " (error-message-string err)))))
374
375 ;; ARG is a file name.
376 ;; Collapse multiple slashes to single slashes.
377 (setq arg (command-line-normalize-file-name arg))
378 (push (list arg lineno columnno) files))
379 (setq lineno 1)
380 (setq columnno 0)))))
381 (when files
382 (run-hooks 'pre-command-hook)
383 (server-visit-files files client nowait)
384 (run-hooks 'post-command-hook))
385 ;; CLIENT is now a list (CLIENTNUM BUFFERS...)
386 (if (and (not newframe) (null (cdr client)))
387 ;; This client is empty; get rid of it immediately.
388 (progn
389 (let ((frame (assq (car client) server-frames)))
390 (setq server-frames (delq frame server-frames))
391 (when (frame-live-p (cadr frame)) (delete-frame (cadr frame) 'force)))
392 (delete-process proc)
393 (server-log "Close empty client" proc))
394 ;; We visited some buffer for this client.
395 (or nowait (push client server-clients))
396 (unless (or isearch-mode (minibufferp))
397 (server-switch-buffer (nth 1 client))
398 (run-hooks 'server-switch-hook)
399 (unless nowait
400 (message (substitute-command-keys
401 "When done with a buffer, type \\[server-edit]")))))))
402 ;; Save for later any partial line that remains.
403 (when (> (length string) 0)
404 (process-put proc 'previous-string string)))
405
406 (defun server-goto-line-column (file-line-col)
407 (goto-line (nth 1 file-line-col))
408 (let ((column-number (nth 2 file-line-col)))
409 (if (> column-number 0)
410 (move-to-column (1- column-number)))))
411
412 (defun server-visit-files (files client &optional nowait)
413 "Find FILES and return the list CLIENT with the buffers nconc'd.
414 FILES is an alist whose elements are (FILENAME LINENUMBER COLUMNNUMBER).
415 NOWAIT non-nil means this client is not waiting for the results,
416 so don't mark these buffers specially, just visit them normally."
417 ;; Bind last-nonmenu-event to force use of keyboard, not mouse, for queries.
418 (let ((last-nonmenu-event t) client-record)
419 ;; Restore the current buffer afterward, but not using save-excursion,
420 ;; because we don't want to save point in this buffer
421 ;; if it happens to be one of those specified by the server.
422 (save-current-buffer
423 (dolist (file files)
424 ;; If there is an existing buffer modified or the file is
425 ;; modified, revert it. If there is an existing buffer with
426 ;; deleted file, offer to write it.
427 (let* ((filen (car file))
428 (obuf (get-file-buffer filen)))
429 (push filen file-name-history)
430 (if (and obuf (set-buffer obuf))
431 (progn
432 (cond ((file-exists-p filen)
433 (if (not (verify-visited-file-modtime obuf))
434 (revert-buffer t nil)))
435 (t
436 (if (y-or-n-p
437 (concat "File no longer exists: "
438 filen
439 ", write buffer to file? "))
440 (write-file filen))))
441 (setq server-existing-buffer t)
442 (server-goto-line-column file))
443 (set-buffer (find-file-noselect filen))
444 (server-goto-line-column file)
445 (run-hooks 'server-visit-hook)))
446 (unless nowait
447 ;; When the buffer is killed, inform the clients.
448 (add-hook 'kill-buffer-hook 'server-kill-buffer nil t)
449 (push (car client) server-buffer-clients))
450 (push (current-buffer) client-record)))
451 (nconc client client-record)))
452 \f
453 (defun server-buffer-done (buffer &optional for-killing)
454 "Mark BUFFER as \"done\" for its client(s).
455 This buries the buffer, then returns a list of the form (NEXT-BUFFER KILLED).
456 NEXT-BUFFER is another server buffer, as a suggestion for what to select next,
457 or nil. KILLED is t if we killed BUFFER (typically, because it was visiting
458 a temp file).
459 FOR-KILLING if non-nil indicates that we are called from `kill-buffer'."
460 (let ((next-buffer nil)
461 (killed nil)
462 (old-clients server-clients))
463 (while old-clients
464 (let ((client (car old-clients)))
465 (or next-buffer
466 (setq next-buffer (nth 1 (memq buffer client))))
467 (delq buffer client)
468 ;; Delete all dead buffers from CLIENT.
469 (let ((tail client))
470 (while tail
471 (and (bufferp (car tail))
472 (null (buffer-name (car tail)))
473 (delq (car tail) client))
474 (setq tail (cdr tail))))
475 ;; If client now has no pending buffers,
476 ;; tell it that it is done, and forget it entirely.
477 (unless (cdr client)
478 (let ((frame (assq (car client) server-frames)))
479 (setq server-frames (delq frame server-frames))
480 (when (frame-live-p (cadr frame)) (delete-frame (cadr frame) 'force)))
481 (delete-process (car client))
482 (server-log "Close" (car client))
483 (setq server-clients (delq client server-clients))))
484 (setq old-clients (cdr old-clients)))
485 (if (and (bufferp buffer) (buffer-name buffer))
486 ;; We may or may not kill this buffer;
487 ;; if we do, do not call server-buffer-done recursively
488 ;; from kill-buffer-hook.
489 (let ((server-kill-buffer-running t))
490 (with-current-buffer buffer
491 (setq server-buffer-clients nil)
492 (run-hooks 'server-done-hook))
493 ;; Notice whether server-done-hook killed the buffer.
494 (if (null (buffer-name buffer))
495 (setq killed t)
496 ;; Don't bother killing or burying the buffer
497 ;; when we are called from kill-buffer.
498 (unless for-killing
499 (when (and (not killed)
500 server-kill-new-buffers
501 (with-current-buffer buffer
502 (not server-existing-buffer)))
503 (setq killed t)
504 (bury-buffer buffer)
505 (kill-buffer buffer))
506 (unless killed
507 (if (server-temp-file-p buffer)
508 (progn
509 (kill-buffer buffer)
510 (setq killed t))
511 (bury-buffer buffer)))))))
512 (list next-buffer killed)))
513
514 (defun server-temp-file-p (&optional buffer)
515 "Return non-nil if BUFFER contains a file considered temporary.
516 These are files whose names suggest they are repeatedly
517 reused to pass information to another program.
518
519 The variable `server-temp-file-regexp' controls which filenames
520 are considered temporary."
521 (and (buffer-file-name buffer)
522 (string-match server-temp-file-regexp (buffer-file-name buffer))))
523
524 (defun server-done ()
525 "Offer to save current buffer, mark it as \"done\" for clients.
526 This kills or buries the buffer, then returns a list
527 of the form (NEXT-BUFFER KILLED). NEXT-BUFFER is another server buffer,
528 as a suggestion for what to select next, or nil.
529 KILLED is t if we killed BUFFER, which happens if it was created
530 specifically for the clients and did not exist before their request for it."
531 (when server-buffer-clients
532 (if (server-temp-file-p)
533 ;; For a temp file, save, and do make a non-numeric backup
534 ;; (unless make-backup-files is nil).
535 (let ((version-control nil)
536 (buffer-backed-up nil))
537 (save-buffer))
538 (if (and (buffer-modified-p)
539 buffer-file-name
540 (y-or-n-p (concat "Save file " buffer-file-name "? ")))
541 (save-buffer)))
542 (server-buffer-done (current-buffer))))
543
544 ;; Ask before killing a server buffer.
545 ;; It was suggested to release its client instead,
546 ;; but I think that is dangerous--the client would proceed
547 ;; using whatever is on disk in that file. -- rms.
548 (defun server-kill-buffer-query-function ()
549 (or (not server-buffer-clients)
550 (yes-or-no-p (format "Buffer `%s' still has clients; kill it? "
551 (buffer-name (current-buffer))))))
552
553 (add-hook 'kill-buffer-query-functions
554 'server-kill-buffer-query-function)
555
556 (defun server-kill-emacs-query-function ()
557 (let (live-client
558 (tail server-clients))
559 ;; See if any clients have any buffers that are still alive.
560 (while tail
561 (if (memq t (mapcar 'stringp (mapcar 'buffer-name (cdr (car tail)))))
562 (setq live-client t))
563 (setq tail (cdr tail)))
564 (or (not live-client)
565 (yes-or-no-p "Server buffers still have clients; exit anyway? "))))
566
567 (add-hook 'kill-emacs-query-functions 'server-kill-emacs-query-function)
568
569 (defvar server-kill-buffer-running nil
570 "Non-nil while `server-kill-buffer' or `server-buffer-done' is running.")
571
572 (defun server-kill-buffer ()
573 ;; Prevent infinite recursion if user has made server-done-hook
574 ;; call kill-buffer.
575 (or server-kill-buffer-running
576 (and server-buffer-clients
577 (let ((server-kill-buffer-running t))
578 (when server-process
579 (server-buffer-done (current-buffer) t))))))
580 \f
581 (defun server-edit (&optional arg)
582 "Switch to next server editing buffer; say \"Done\" for current buffer.
583 If a server buffer is current, it is marked \"done\" and optionally saved.
584 The buffer is also killed if it did not exist before the clients asked for it.
585 When all of a client's buffers are marked as \"done\", the client is notified.
586
587 Temporary files such as MH <draft> files are always saved and backed up,
588 no questions asked. (The variable `make-backup-files', if nil, still
589 inhibits a backup; you can set it locally in a particular buffer to
590 prevent a backup for it.) The variable `server-temp-file-regexp' controls
591 which filenames are considered temporary.
592
593 If invoked with a prefix argument, or if there is no server process running,
594 starts server process and that is all. Invoked by \\[server-edit]."
595 (interactive "P")
596 (if (or arg
597 (not server-process)
598 (memq (process-status server-process) '(signal exit)))
599 (server-start nil)
600 (apply 'server-switch-buffer (server-done))))
601
602 (defun server-switch-buffer (&optional next-buffer killed-one)
603 "Switch to another buffer, preferably one that has a client.
604 Arg NEXT-BUFFER is a suggestion; if it is a live buffer, use it."
605 ;; KILLED-ONE is t in a recursive call
606 ;; if we have already killed one temp-file server buffer.
607 ;; This means we should avoid the final "switch to some other buffer"
608 ;; since we've already effectively done that.
609 (if (null next-buffer)
610 (if server-clients
611 (let ((buffer (nth 1 (car server-clients))))
612 (and buffer (server-switch-buffer buffer killed-one)))
613 (unless (or killed-one (window-dedicated-p (selected-window)))
614 (switch-to-buffer (other-buffer))
615 (message "No server buffers remain to edit")))
616 (if (not (buffer-name next-buffer))
617 ;; If NEXT-BUFFER is a dead buffer, remove the server records for it
618 ;; and try the next surviving server buffer.
619 (apply 'server-switch-buffer (server-buffer-done next-buffer))
620 ;; OK, we know next-buffer is live, let's display and select it.
621 (if (functionp server-window)
622 (funcall server-window next-buffer)
623 (let ((win (get-buffer-window next-buffer 0)))
624 (if (and win (not server-window))
625 ;; The buffer is already displayed: just reuse the window.
626 (let ((frame (window-frame win)))
627 (if (eq (frame-visible-p frame) 'icon)
628 (raise-frame frame))
629 (select-window win)
630 (set-buffer next-buffer))
631 ;; Otherwise, let's find an appropriate window.
632 (cond ((and (windowp server-window)
633 (window-live-p server-window))
634 (select-window server-window))
635 ((framep server-window)
636 (if (not (frame-live-p server-window))
637 (setq server-window (make-frame)))
638 (select-window (frame-selected-window server-window))))
639 (if (window-minibuffer-p (selected-window))
640 (select-window (next-window nil 'nomini 0)))
641 ;; Move to a non-dedicated window, if we have one.
642 (when (window-dedicated-p (selected-window))
643 (select-window
644 (get-window-with-predicate
645 (lambda (w)
646 (and (not (window-dedicated-p w))
647 (equal (frame-parameter (window-frame w) 'display)
648 (frame-parameter (selected-frame) 'display))))
649 'nomini 'visible (selected-window))))
650 (condition-case nil
651 (switch-to-buffer next-buffer)
652 ;; After all the above, we might still have ended up with
653 ;; a minibuffer/dedicated-window (if there's no other).
654 (error (pop-to-buffer next-buffer)))))))))
655
656 (global-set-key "\C-x#" 'server-edit)
657
658 (defun server-unload-hook ()
659 (server-start t)
660 (remove-hook 'kill-buffer-query-functions 'server-kill-buffer-query-function)
661 (remove-hook 'kill-emacs-query-functions 'server-kill-emacs-query-function)
662 (remove-hook 'kill-buffer-hook 'server-kill-buffer))
663 \f
664 (provide 'server)
665
666 ;;; arch-tag: 1f7ecb42-f00a-49f8-906d-61995d84c8d6
667 ;;; server.el ends here