Make all frames created in an emacsclient session belong to that client.
[emacs.git] / lisp / server.el
blob40806a1b6c3ae998db8c2e0a4a1bfef329c9b309
1 ;;; server.el --- Lisp code for GNU Emacs running as server process
3 ;; Copyright (C) 1986, 1987, 1992, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
4 ;; 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
6 ;; Author: William Sommerfeld <wesommer@athena.mit.edu>
7 ;; Maintainer: FSF
8 ;; Keywords: processes
10 ;; Changes by peck@sun.com and by rms.
11 ;; Overhaul by Karoly Lorentey <lorentey@elte.hu> for multi-tty support.
13 ;; This file is part of GNU Emacs.
15 ;; GNU Emacs is free software; you can redistribute it and/or modify
16 ;; it under the terms of the GNU General Public License as published by
17 ;; the Free Software Foundation; either version 2, or (at your option)
18 ;; any later version.
20 ;; GNU Emacs is distributed in the hope that it will be useful,
21 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
22 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
23 ;; GNU General Public License for more details.
25 ;; You should have received a copy of the GNU General Public License
26 ;; along with GNU Emacs; see the file COPYING. If not, write to the
27 ;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
28 ;; Boston, MA 02110-1301, USA.
30 ;;; Commentary:
32 ;; This Lisp code is run in Emacs when it is to operate as
33 ;; a server for other processes.
35 ;; Load this library and do M-x server-edit to enable Emacs as a server.
36 ;; Emacs opens up a socket for communication with clients. If there are no
37 ;; client buffers to edit, server-edit acts like (switch-to-buffer
38 ;; (other-buffer))
40 ;; When some other program runs "the editor" to edit a file,
41 ;; "the editor" can be the Emacs client program ../lib-src/emacsclient.
42 ;; This program transmits the file names to Emacs through
43 ;; the server subprocess, and Emacs visits them and lets you edit them.
45 ;; Note that any number of clients may dispatch files to Emacs to be edited.
47 ;; When you finish editing a Server buffer, again call server-edit
48 ;; to mark that buffer as done for the client and switch to the next
49 ;; Server buffer. When all the buffers for a client have been edited
50 ;; and exited with server-edit, the client "editor" will return
51 ;; to the program that invoked it.
53 ;; Your editing commands and Emacs's display output go to and from
54 ;; the terminal in the usual way. Thus, server operation is possible
55 ;; only when Emacs can talk to the terminal at the time you invoke
56 ;; the client. This is possible in four cases:
58 ;; 1. On a window system, where Emacs runs in one window and the
59 ;; program that wants to use "the editor" runs in another.
61 ;; 2. On a multi-terminal system, where Emacs runs on one terminal and the
62 ;; program that wants to use "the editor" runs on another.
64 ;; 3. When the program that wants to use "the editor" is running
65 ;; as a subprocess of Emacs.
67 ;; 4. On a system with job control, when Emacs is suspended, the program
68 ;; that wants to use "the editor" will stop and display
69 ;; "Waiting for Emacs...". It can then be suspended, and Emacs can be
70 ;; brought into the foreground for editing. When done editing, Emacs is
71 ;; suspended again, and the client program is brought into the foreground.
73 ;; The buffer local variable "server-buffer-clients" lists
74 ;; the clients who are waiting for this buffer to be edited.
75 ;; The global variable "server-clients" lists all the waiting clients,
76 ;; and which files are yet to be edited for each.
78 ;;; Code:
80 (eval-when-compile (require 'cl))
82 (defgroup server nil
83 "Emacs running as a server process."
84 :group 'external)
86 (defcustom server-visit-hook nil
87 "*Hook run when visiting a file for the Emacs server."
88 :group 'server
89 :type 'hook)
91 (defcustom server-switch-hook nil
92 "*Hook run when switching to a buffer for the Emacs server."
93 :group 'server
94 :type 'hook)
96 (defcustom server-done-hook nil
97 "*Hook run when done editing a buffer for the Emacs server."
98 :group 'server
99 :type 'hook)
101 (defvar server-process nil
102 "The current server process.")
104 (defvar server-clients nil
105 "List of current server clients.
106 Each element is (PROC PROPERTIES...) where PROC is a process object,
107 and PROPERTIES is an association list of client properties.")
109 (defvar server-buffer-clients nil
110 "List of client ids for clients requesting editing of current buffer.")
111 (make-variable-buffer-local 'server-buffer-clients)
112 ;; Changing major modes should not erase this local.
113 (put 'server-buffer-clients 'permanent-local t)
115 (defcustom server-window nil
116 "*Specification of the window to use for selecting Emacs server buffers.
117 If nil, use the selected window.
118 If it is a function, it should take one argument (a buffer) and
119 display and select it. A common value is `pop-to-buffer'.
120 If it is a window, use that.
121 If it is a frame, use the frame's selected window.
123 It is not meaningful to set this to a specific frame or window with Custom.
124 Only programs can do so."
125 :group 'server
126 :version "22.1"
127 :type '(choice (const :tag "Use selected window"
128 :match (lambda (widget value)
129 (not (functionp value)))
130 nil)
131 (function-item :tag "Use pop-to-buffer" pop-to-buffer)
132 (function :tag "Other function")))
134 (defcustom server-temp-file-regexp "^/tmp/Re\\|/draft$"
135 "*Regexp matching names of temporary files.
136 These are deleted and reused after each edit by the programs that
137 invoke the Emacs server."
138 :group 'server
139 :type 'regexp)
141 (defcustom server-kill-new-buffers t
142 "*Whether to kill buffers when done with them.
143 If non-nil, kill a buffer unless it already existed before editing
144 it with Emacs server. If nil, kill only buffers as specified by
145 `server-temp-file-regexp'.
146 Please note that only buffers are killed that still have a client,
147 i.e. buffers visited which \"emacsclient --no-wait\" are never killed in
148 this way."
149 :group 'server
150 :type 'boolean
151 :version "21.1")
153 (or (assq 'server-buffer-clients minor-mode-alist)
154 (setq minor-mode-alist (cons '(server-buffer-clients " Server") minor-mode-alist)))
156 (defvar server-existing-buffer nil
157 "Non-nil means the buffer existed before the server was asked to visit it.
158 This means that the server should not kill the buffer when you say you
159 are done with it in the server.")
160 (make-variable-buffer-local 'server-existing-buffer)
162 (defvar server-name "server")
164 (defvar server-socket-dir nil
165 "The directory in which to place the server socket.
166 Initialized by `server-start'.")
168 (defun server-client (proc)
169 "Return the Emacs client corresponding to PROC.
170 PROC must be a process object.
171 The car of the result is PROC; the cdr is an association list.
172 See `server-client-get' and `server-client-set'."
173 (assq proc server-clients))
175 (defun server-client-get (client property)
176 "Get the value of PROPERTY in CLIENT.
177 CLIENT may be a process object, or a client returned by `server-client'.
178 Return nil if CLIENT has no such property."
179 (or (listp client) (setq client (server-client client)))
180 (cdr (assq property (cdr client))))
182 (defun server-client-set (client property value)
183 "Set the PROPERTY to VALUE in CLIENT, and return VALUE.
184 CLIENT may be a process object, or a client returned by `server-client'."
185 (let (p proc)
186 (if (listp client)
187 (setq proc (car client))
188 (setq proc client
189 client (server-client client)))
190 (setq p (assq property client))
191 (cond
192 (p (setcdr p value))
193 (client (setcdr client (cons (cons property value) (cdr client))))
194 (t (setq server-clients
195 `((,proc (,property . ,value)) . ,server-clients))))
196 value))
198 (defun server-clients-with (property value)
199 "Return a list of clients with PROPERTY set to VALUE."
200 (let (result)
201 (dolist (client server-clients result)
202 (when (equal value (server-client-get client property))
203 (setq result (cons (car client) result))))))
205 (defun server-add-client (proc)
206 "Create a client for process PROC, if it doesn't already have one.
207 New clients have no properties."
208 (unless (server-client proc)
209 (setq server-clients (cons (cons proc nil)
210 server-clients))))
212 (defun server-getenv-from (env variable)
213 "Get the value of VARIABLE in ENV.
214 VARIABLE should be a string. Value is nil if VARIABLE is
215 undefined in ENV. Otherwise, value is a string.
217 ENV should be in the same format as `process-environment'."
218 (let (entry result)
219 (while (and env (null result))
220 (setq entry (car env)
221 env (cdr env))
222 (if (and (> (length entry) (length variable))
223 (eq ?= (aref entry (length variable)))
224 (equal variable (substring entry 0 (length variable))))
225 (setq result (substring entry (+ (length variable) 1)))))
226 result))
228 (defmacro server-with-environment (env vars &rest body)
229 "Evaluate BODY with environment variables VARS set to those in ENV.
230 The environment variables are then restored to their previous values.
232 VARS should be a list of strings.
233 ENV should be in the same format as `process-environment'."
234 (declare (indent 2))
235 (let ((oldvalues (make-symbol "oldvalues"))
236 (var (make-symbol "var"))
237 (value (make-symbol "value"))
238 (pair (make-symbol "pair")))
239 `(let (,oldvalues)
240 (dolist (,var ,vars)
241 (let ((,value (server-getenv-from ,env ,var)))
242 (setq ,oldvalues (cons (cons ,var (getenv ,var)) ,oldvalues))
243 (setenv ,var ,value)))
244 (unwind-protect
245 (progn ,@body)
246 (dolist (,pair ,oldvalues)
247 (setenv (car ,pair) (cdr ,pair)))))))
249 (defun server-delete-client (client &optional noframe)
250 "Delete CLIENT, including its buffers, terminals and frames.
251 If NOFRAME is non-nil, let the frames live. (To be used from
252 `delete-frame-functions'."
253 ;; Force a new lookup of client (prevents infinite recursion).
254 (setq client (server-client
255 (if (listp client) (car client) client)))
256 (let ((proc (car client))
257 (buffers (server-client-get client 'buffers)))
258 (when client
259 (setq server-clients (delq client server-clients))
261 (dolist (buf buffers)
262 (when (buffer-live-p buf)
263 (with-current-buffer buf
264 ;; Remove PROC from the clients of each buffer.
265 (setq server-buffer-clients (delq proc server-buffer-clients))
266 ;; Kill the buffer if necessary.
267 (when (and (null server-buffer-clients)
268 (or (and server-kill-new-buffers
269 (not server-existing-buffer))
270 (server-temp-file-p)))
271 (kill-buffer (current-buffer))))))
273 ;; Delete the client's frames.
274 (unless noframe
275 (dolist (frame (frame-list))
276 (when (and (frame-live-p frame)
277 (equal proc (frame-parameter frame 'client)))
278 ;; Prevent `server-handle-delete-frame' from calling us
279 ;; recursively.
280 (set-frame-parameter frame 'client nil)
281 (delete-frame frame))))
283 ;; Delete the client's tty.
284 (let ((terminal (server-client-get client 'terminal)))
285 (when (eq (terminal-live-p terminal) t)
286 (delete-terminal terminal)))
288 ;; Delete the client's process.
289 (if (eq (process-status (car client)) 'open)
290 (delete-process (car client)))
292 (server-log "Deleted" proc))))
294 (defun server-log (string &optional client)
295 "If a *server* buffer exists, write STRING to it for logging purposes.
296 If CLIENT is non-nil, add a description of it to the logged
297 message."
298 (if (get-buffer "*server*")
299 (with-current-buffer "*server*"
300 (goto-char (point-max))
301 (insert (current-time-string)
302 (cond
303 ((null client) " ")
304 ((listp client) (format " %s: " (car client)))
305 (t (format " %s: " client)))
306 string)
307 (or (bolp) (newline)))))
309 (defun server-sentinel (proc msg)
310 "The process sentinel for Emacs server connections."
311 ;; If this is a new client process, set the query-on-exit flag to nil
312 ;; for this process (it isn't inherited from the server process).
313 (when (and (eq (process-status proc) 'open)
314 (process-query-on-exit-flag proc))
315 (set-process-query-on-exit-flag proc nil))
316 (server-log (format "Status changed to %s: %s" (process-status proc) msg) proc)
317 (server-delete-client proc))
319 (defun server-handle-delete-frame (frame)
320 "Delete the client connection when the emacsclient frame is deleted."
321 (let ((proc (frame-parameter frame 'client)))
322 (when (and (frame-live-p frame)
323 proc
324 ;; See if this is the last frame for this client.
325 (< 1 (let ((frame-num 0))
326 (dolist ((f (frame-list)))
327 (when (eq proc (frame-parameter f 'client))
328 (setq frame-num (1+ frame-num))))
329 frame-num)))
330 (server-log (format "server-handle-delete-frame, frame %s" frame) proc)
331 (server-delete-client proc 'noframe)))) ; Let delete-frame delete the frame later.
333 (defun server-handle-suspend-tty (terminal)
334 "Notify the emacsclient process to suspend itself when its tty device is suspended."
335 (dolist (proc (server-clients-with 'terminal terminal))
336 (server-log (format "server-handle-suspend-tty, terminal %s" terminal) proc)
337 (condition-case err
338 (server-send-string proc "-suspend \n")
339 (file-error (condition-case nil (server-delete-client proc) (error nil))))))
341 (defun server-unquote-arg (arg)
342 "Remove &-quotation from ARG.
343 See `server-quote-arg' and `server-process-filter'."
344 (replace-regexp-in-string
345 "&." (lambda (s)
346 (case (aref s 1)
347 (?& "&")
348 (?- "-")
349 (?n "\n")
350 (t " ")))
351 arg t t))
353 (defun server-quote-arg (arg)
354 "In ARG, insert a & before each &, each space, each newline, and -.
355 Change spaces to underscores, too, so that the return value never
356 contains a space.
358 See `server-unquote-arg' and `server-process-filter'."
359 (replace-regexp-in-string
360 "[-&\n ]" (lambda (s)
361 (case (aref s 0)
362 (?& "&&")
363 (?- "&-")
364 (?\n "&n")
365 (?\s "&_")))
366 arg t t))
368 (defun server-send-string (proc string)
369 "A wrapper around `proc-send-string' for logging."
370 (server-log (concat "Sent " string) proc)
371 (process-send-string proc string))
373 (defun server-ensure-safe-dir (dir)
374 "Make sure DIR is a directory with no race-condition issues.
375 Creates the directory if necessary and makes sure:
376 - there's no symlink involved
377 - it's owned by us
378 - it's not readable/writable by anybody else."
379 (setq dir (directory-file-name dir))
380 (let ((attrs (file-attributes dir)))
381 (unless attrs
382 (letf (((default-file-modes) ?\700)) (make-directory dir))
383 (setq attrs (file-attributes dir)))
384 ;; Check that it's safe for use.
385 (unless (and (eq t (car attrs)) (eq (nth 2 attrs) (user-uid))
386 (zerop (logand ?\077 (file-modes dir))))
387 (error "The directory %s is unsafe" dir))))
389 ;;;###autoload
390 (defun server-start (&optional leave-dead)
391 "Allow this Emacs process to be a server for client processes.
392 This starts a server communications subprocess through which
393 client \"editors\" can send your editing commands to this Emacs
394 job. To use the server, set up the program `emacsclient' in the
395 Emacs distribution as your standard \"editor\".
397 Prefix arg LEAVE-DEAD means just kill any existing server
398 communications subprocess."
399 (interactive "P")
400 (when (or
401 (not server-clients)
402 (yes-or-no-p
403 "The current server still has clients; delete them? "))
404 ;; It is safe to get the user id now.
405 (setq server-socket-dir (or server-socket-dir
406 (format "/tmp/emacs%d" (user-uid))))
407 ;; Make sure there is a safe directory in which to place the socket.
408 (server-ensure-safe-dir server-socket-dir)
409 ;; kill it dead!
410 (if server-process
411 (condition-case () (delete-process server-process) (error nil)))
412 ;; Delete the socket files made by previous server invocations.
413 (condition-case ()
414 (delete-file (expand-file-name server-name server-socket-dir))
415 (error nil))
416 ;; If this Emacs already had a server, clear out associated status.
417 (while server-clients
418 (server-delete-client (car server-clients)))
419 (if leave-dead
420 (progn
421 (server-log (message "Server stopped"))
422 (setq server-process nil))
423 (if server-process
424 (server-log (message "Restarting server"))
425 (server-log (message "Starting server")))
426 (letf (((default-file-modes) ?\700))
427 (add-hook 'suspend-tty-functions 'server-handle-suspend-tty)
428 (add-hook 'delete-frame-functions 'server-handle-delete-frame)
429 (add-hook 'kill-buffer-query-functions 'server-kill-buffer-query-function)
430 (add-hook 'kill-emacs-query-functions 'server-kill-emacs-query-function)
431 (setq server-process
432 (make-network-process
433 :name "server" :family 'local :server t :noquery t
434 :service (expand-file-name server-name server-socket-dir)
435 :sentinel 'server-sentinel :filter 'server-process-filter
436 ;; We must receive file names without being decoded.
437 ;; Those are decoded by server-process-filter according
438 ;; to file-name-coding-system.
439 :coding 'raw-text))))))
441 ;;;###autoload
442 (define-minor-mode server-mode
443 "Toggle Server mode.
444 With ARG, turn Server mode on if ARG is positive, off otherwise.
445 Server mode runs a process that accepts commands from the
446 `emacsclient' program. See `server-start' and Info node `Emacs server'."
447 :global t
448 :group 'server
449 :version "22.1"
450 ;; Fixme: Should this check for an existing server socket and do
451 ;; nothing if there is one (for multiple Emacs sessions)?
452 (server-start (not server-mode)))
454 (defun server-process-filter (proc string)
455 "Process a request from the server to edit some files.
456 PROC is the server process. STRING consists of a sequence of
457 commands prefixed by a dash. Some commands have arguments; these
458 are &-quoted and need to be decoded by `server-unquote-arg'. The
459 filter parses and executes these commands.
461 To illustrate the protocol, here is an example command that
462 emacsclient sends to create a new X frame (note that the whole
463 sequence is sent on a single line):
465 -version 21.3.50 xterm
466 -env HOME /home/lorentey
467 -env DISPLAY :0.0
468 ... lots of other -env commands
469 -display :0.0
470 -window-system
472 The server normally sends back the single command `-good-version'
473 as a response.
475 The following commands are accepted by the server:
477 `-version CLIENT-VERSION'
478 Check version numbers between server and client, and signal an
479 error if there is a mismatch. The server replies with
480 `-good-version' to confirm the match.
482 `-env NAME=VALUE'
483 An environment variable on the client side.
485 `-current-frame'
486 Forbid the creation of new frames.
488 `-nowait'
489 Request that the next frame created should not be
490 associated with this client.
492 `-display DISPLAY'
493 Set the display name to open X frames on.
495 `-position LINE[:COLUMN]'
496 Go to the given line and column number
497 in the next file opened.
499 `-file FILENAME'
500 Load the given file in the current frame.
502 `-eval EXPR'
503 Evaluate EXPR as a Lisp expression and return the
504 result in -print commands.
506 `-window-system'
507 Open a new X frame.
509 `-tty DEVICENAME TYPE'
510 Open a new tty frame at the client.
512 `-resume'
513 Resume this tty frame. The client sends this string when it
514 gets the SIGCONT signal and it is the foreground process on its
515 controlling tty.
517 `-suspend'
518 Suspend this tty frame. The client sends this string in
519 response to SIGTSTP and SIGTTOU. The server must cease all I/O
520 on this tty until it gets a -resume command.
522 `-ignore COMMENT'
523 Do nothing, but put the comment in the server
524 log. Useful for debugging.
527 The following commands are accepted by the client:
529 `-good-version'
530 Signals a version match between the client and the server.
532 `-emacs-pid PID'
533 Describes the process id of the Emacs process;
534 used to forward window change signals to it.
536 `-window-system-unsupported'
537 Signals that the server does not
538 support creating X frames; the client must try again with a tty
539 frame.
541 `-print STRING'
542 Print STRING on stdout. Used to send values
543 returned by -eval.
545 `-error DESCRIPTION'
546 Signal an error (but continue processing).
548 `-suspend'
549 Suspend this terminal, i.e., stop the client process. Sent
550 when the user presses C-z."
551 (server-log (concat "Received " string) proc)
552 (let ((prev (process-get proc 'previous-string)))
553 (when prev
554 (setq string (concat prev string))
555 (process-put proc 'previous-string nil)))
556 (condition-case err
557 (progn
558 (server-add-client proc)
559 ;; If the input is multiple lines,
560 ;; process each line individually.
561 (while (string-match "\n" string)
562 (let ((request (substring string 0 (match-beginning 0)))
563 (coding-system (and default-enable-multibyte-characters
564 (or file-name-coding-system
565 default-file-name-coding-system)))
566 (client (server-client proc))
567 current-frame
568 nowait ; t if emacsclient does not want to wait for us.
569 frame ; The frame that was opened for the client (if any).
570 display ; Open the frame on this display.
571 dontkill ; t if the client should not be killed.
573 (files nil)
574 (lineno 1)
575 (columnno 0))
576 ;; Remove this line from STRING.
577 (setq string (substring string (match-end 0)))
578 (while (string-match " *[^ ]* " request)
579 (let ((arg (substring request (match-beginning 0) (1- (match-end 0)))))
580 (setq request (substring request (match-end 0)))
581 (cond
582 ;; -version CLIENT-VERSION:
583 ;; Check version numbers, signal an error if there is a mismatch.
584 ((and (equal "-version" arg)
585 (string-match "\\([0-9.]+\\) " request))
586 (let* ((client-version (match-string 1 request))
587 (truncated-emacs-version
588 (substring emacs-version 0 (length client-version))))
589 (setq request (substring request (match-end 0)))
590 (if (equal client-version truncated-emacs-version)
591 (progn
592 (server-send-string proc "-good-version \n")
593 (server-client-set client 'version client-version))
594 (error (concat "Version mismatch: Emacs is "
595 truncated-emacs-version
596 ", emacsclient is " client-version)))))
598 ;; -nowait: Emacsclient won't wait for a result.
599 ((equal "-nowait" arg) (setq nowait t))
601 ;; -current-frame: Don't create frames.
602 ((equal "-current-frame" arg) (setq current-frame t))
604 ;; -display DISPLAY:
605 ;; Open X frames on the given display instead of the default.
606 ((and (equal "-display" arg) (string-match "\\([^ ]*\\) " request))
607 (setq display (match-string 1 request)
608 request (substring request (match-end 0))))
610 ;; -window-system: Open a new X frame.
611 ((equal "-window-system" arg)
612 (unless (server-client-get client 'version)
613 (error "Protocol error; make sure to use the correct version of emacsclient"))
614 (unless current-frame
615 (if (fboundp 'x-create-frame)
616 (let ((params (if nowait
617 ;; Flag frame as client-created, but use a dummy client.
618 ;; This will prevent the frame from being deleted when
619 ;; emacsclient quits while also preventing
620 ;; `server-save-buffers-kill-terminal' from unexpectedly
621 ;; killing emacs on that frame.
622 (list (cons 'client 'nowait) (cons 'environment env))
623 (list (cons 'client proc) (cons 'environment env)))))
624 (setq frame (make-frame-on-display
625 (or display
626 (frame-parameter nil 'display)
627 (getenv "DISPLAY")
628 (error "Please specify display"))
629 params))
630 (server-log (format "%s created" frame) proc)
631 ;; XXX We need to ensure the parameters are
632 ;; really set because Emacs forgets unhandled
633 ;; initialization parameters for X frames at
634 ;; the moment.
635 (modify-frame-parameters frame params)
636 (select-frame frame)
637 (server-client-set client 'frame frame)
638 (server-client-set client 'terminal (frame-terminal frame))
639 (setq dontkill t))
640 ;; This emacs does not support X.
641 (server-log "Window system unsupported" proc)
642 (server-send-string proc "-window-system-unsupported \n")
643 (setq dontkill t))))
645 ;; -resume: Resume a suspended tty frame.
646 ((equal "-resume" arg)
647 (let ((terminal (server-client-get client 'terminal)))
648 (setq dontkill t)
649 (when (eq (terminal-live-p terminal) t)
650 (resume-tty terminal))))
652 ;; -suspend: Suspend the client's frame. (In case we
653 ;; get out of sync, and a C-z sends a SIGTSTP to
654 ;; emacsclient.)
655 ((equal "-suspend" arg)
656 (let ((terminal (server-client-get client 'terminal)))
657 (setq dontkill t)
658 (when (eq (terminal-live-p terminal) t)
659 (suspend-tty terminal))))
661 ;; -ignore COMMENT: Noop; useful for debugging emacsclient.
662 ;; (The given comment appears in the server log.)
663 ((and (equal "-ignore" arg) (string-match "\\([^ ]*\\) " request))
664 (setq dontkill t
665 request (substring request (match-end 0))))
667 ;; -tty DEVICE-NAME TYPE: Open a new tty frame at the client.
668 ((and (equal "-tty" arg) (string-match "\\([^ ]*\\) \\([^ ]*\\) " request))
669 (let ((tty (server-unquote-arg (match-string 1 request)))
670 (type (server-unquote-arg (match-string 2 request))))
671 (setq request (substring request (match-end 0)))
672 (unless (server-client-get client 'version)
673 (error "Protocol error; make sure you use the correct version of emacsclient"))
674 (unless current-frame
675 (server-with-environment env
676 '("LANG" "LC_CTYPE" "LC_ALL"
677 ;; For tgetent(3); list according to ncurses(3).
678 "BAUDRATE" "COLUMNS" "ESCDELAY" "HOME" "LINES"
679 "NCURSES_ASSUMED_COLORS" "NCURSES_NO_PADDING"
680 "NCURSES_NO_SETBUF" "TERM" "TERMCAP" "TERMINFO"
681 "TERMINFO_DIRS" "TERMPATH")
682 (setq frame (make-frame-on-tty tty type
683 ;; Ignore nowait here; we always need to clean
684 ;; up opened ttys when the client dies.
685 `((client . ,proc)
686 (environment . ,env)))))
687 (select-frame frame)
688 (server-client-set client 'frame frame)
689 (server-client-set client 'tty (terminal-name frame))
690 (server-client-set client 'terminal (frame-terminal frame))
692 ;; Reply with our pid.
693 (server-send-string proc (concat "-emacs-pid " (number-to-string (emacs-pid)) "\n"))
694 (setq dontkill t))))
696 ;; -position LINE: Go to the given line in the next file.
697 ((and (equal "-position" arg) (string-match "\\(\\+[0-9]+\\) " request))
698 (setq lineno (string-to-number (substring (match-string 1 request) 1))
699 request (substring request (match-end 0))))
701 ;; -position LINE:COLUMN: Set point to the given position in the next file.
702 ((and (equal "-position" arg) (string-match "\\+\\([0-9]+\\):\\([0-9]+\\) " request))
703 (setq lineno (string-to-number (match-string 1 request))
704 columnno (string-to-number (match-string 2 request))
705 request (substring request (match-end 0))))
707 ;; -file FILENAME: Load the given file.
708 ((and (equal "-file" arg) (string-match "\\([^ ]+\\) " request))
709 (let ((file (server-unquote-arg (match-string 1 request))))
710 (setq request (substring request (match-end 0)))
711 (if coding-system
712 (setq file (decode-coding-string file coding-system)))
713 (setq file (command-line-normalize-file-name file))
714 (push (list file lineno columnno) files)
715 (server-log (format "New file: %s (%d:%d)" file lineno columnno) proc))
716 (setq lineno 1
717 columnno 0))
719 ;; -eval EXPR: Evaluate a Lisp expression.
720 ((and (equal "-eval" arg) (string-match "\\([^ ]+\\) " request))
721 (let ((expr (server-unquote-arg (match-string 1 request))))
722 (setq request (substring request (match-end 0)))
723 (if coding-system
724 (setq expr (decode-coding-string expr coding-system)))
725 (let ((v (eval (car (read-from-string expr)))))
726 (when (and (not frame) v)
727 (with-temp-buffer
728 (let ((standard-output (current-buffer)))
729 (pp v)
730 (server-send-string
731 proc (format "-print %s\n"
732 (server-quote-arg
733 (buffer-substring-no-properties (point-min)
734 (point-max)))))))))
735 (setq lineno 1
736 columnno 0)))
738 ;; -env NAME=VALUE: An environment variable.
739 ((and (equal "-env" arg) (string-match "\\([^ ]+\\) " request))
740 (let ((var (server-unquote-arg (match-string 1 request))))
741 ;; XXX Variables should be encoded as in getenv/setenv.
742 (setq request (substring request (match-end 0)))
743 (setq env (cons var env))))
745 ;; Unknown command.
746 (t (error "Unknown command: %s" arg)))))
748 (let (buffers)
749 (when files
750 (run-hooks 'pre-command-hook)
751 (setq buffers (server-visit-files files client nowait))
752 (run-hooks 'post-command-hook))
754 (when frame
755 (with-selected-frame frame
756 (switch-to-buffer (or (car buffers)
757 (get-buffer-create "*scratch*")))
758 (unless inhibit-splash-screen
759 (display-splash-screen))
760 (display-startup-echo-area-message)))
762 ;; Delete the client if necessary.
763 (cond
764 (nowait
765 ;; Client requested nowait; return immediately.
766 (server-log "Close nowait client" proc)
767 (server-delete-client proc))
768 ((and (not dontkill) (null buffers))
769 ;; This client is empty; get rid of it immediately.
770 (server-log "Close empty client" proc)
771 (server-delete-client proc)))
772 (cond
773 ((or isearch-mode (minibufferp))
774 nil)
775 ((and frame (null buffers))
776 (message "%s" (substitute-command-keys
777 "When done with this frame, type \\[delete-frame]")))
778 ((not (null buffers))
779 (server-switch-buffer (car buffers))
780 (run-hooks 'server-switch-hook)
781 (unless nowait
782 (message "%s" (substitute-command-keys
783 "When done with a buffer, type \\[server-edit]"))))))))
785 ;; Save for later any partial line that remains.
786 (when (> (length string) 0)
787 (process-put proc 'previous-string string)))
788 ;; condition-case
789 (error (ignore-errors
790 (server-send-string
791 proc (concat "-error " (server-quote-arg (error-message-string err))))
792 (setq string "")
793 (server-log (error-message-string err) proc)
794 (delete-process proc)))))
796 (defun server-goto-line-column (file-line-col)
797 "Move point to the position indicated in FILE-LINE-COL.
798 FILE-LINE-COL should be a three-element list as described in
799 `server-visit-files'."
800 (goto-line (nth 1 file-line-col))
801 (let ((column-number (nth 2 file-line-col)))
802 (if (> column-number 0)
803 (move-to-column (1- column-number)))))
805 (defun server-visit-files (files client &optional nowait)
806 "Find FILES and return a list of buffers created.
807 FILES is an alist whose elements are (FILENAME LINENUMBER COLUMNNUMBER).
808 CLIENT is the client that requested this operation.
809 NOWAIT non-nil means this client is not waiting for the results,
810 so don't mark these buffers specially, just visit them normally."
811 ;; Bind last-nonmenu-event to force use of keyboard, not mouse, for queries.
812 (let ((last-nonmenu-event t) client-record)
813 ;; Restore the current buffer afterward, but not using save-excursion,
814 ;; because we don't want to save point in this buffer
815 ;; if it happens to be one of those specified by the server.
816 (save-current-buffer
817 (dolist (file files)
818 ;; If there is an existing buffer modified or the file is
819 ;; modified, revert it. If there is an existing buffer with
820 ;; deleted file, offer to write it.
821 (let* ((filen (car file))
822 (obuf (get-file-buffer filen)))
823 (push filen file-name-history)
824 (if (and obuf (set-buffer obuf))
825 (progn
826 (cond ((file-exists-p filen)
827 (if (not (verify-visited-file-modtime obuf))
828 (revert-buffer t nil)))
830 (if (y-or-n-p
831 (concat "File no longer exists: " filen
832 ", write buffer to file? "))
833 (write-file filen))))
834 (setq server-existing-buffer t)
835 (server-goto-line-column file))
836 (set-buffer (find-file-noselect filen))
837 (server-goto-line-column file)
838 (run-hooks 'server-visit-hook)))
839 (unless nowait
840 ;; When the buffer is killed, inform the clients.
841 (add-hook 'kill-buffer-hook 'server-kill-buffer nil t)
842 (push (car client) server-buffer-clients))
843 (push (current-buffer) client-record)))
844 (unless nowait
845 (server-client-set
846 client 'buffers
847 (nconc (server-client-get client 'buffers) client-record)))
848 client-record))
850 (defun server-buffer-done (buffer &optional for-killing)
851 "Mark BUFFER as \"done\" for its client(s).
852 This buries the buffer, then returns a list of the form (NEXT-BUFFER KILLED).
853 NEXT-BUFFER is another server buffer, as a suggestion for what to select next,
854 or nil. KILLED is t if we killed BUFFER (typically, because it was visiting
855 a temp file).
856 FOR-KILLING if non-nil indicates that we are called from `kill-buffer'."
857 (let ((next-buffer nil)
858 (killed nil))
859 (dolist (client server-clients)
860 (let ((buffers (server-client-get client 'buffers)))
861 (or next-buffer
862 (setq next-buffer (nth 1 (memq buffer buffers))))
863 (when buffers ; Ignore bufferless clients.
864 (setq buffers (delq buffer buffers))
865 ;; Delete all dead buffers from CLIENT.
866 (dolist (b buffers)
867 (and (bufferp b)
868 (not (buffer-live-p b))
869 (setq buffers (delq b buffers))))
870 (server-client-set client 'buffers buffers)
871 ;; If client now has no pending buffers,
872 ;; tell it that it is done, and forget it entirely.
873 (unless buffers
874 (server-log "Close" client)
875 (server-delete-client client)))))
876 (if (and (bufferp buffer) (buffer-name buffer))
877 ;; We may or may not kill this buffer;
878 ;; if we do, do not call server-buffer-done recursively
879 ;; from kill-buffer-hook.
880 (let ((server-kill-buffer-running t))
881 (with-current-buffer buffer
882 (setq server-buffer-clients nil)
883 (run-hooks 'server-done-hook))
884 ;; Notice whether server-done-hook killed the buffer.
885 (if (null (buffer-name buffer))
886 (setq killed t)
887 ;; Don't bother killing or burying the buffer
888 ;; when we are called from kill-buffer.
889 (unless for-killing
890 (when (and (not killed)
891 server-kill-new-buffers
892 (with-current-buffer buffer
893 (not server-existing-buffer)))
894 (setq killed t)
895 (bury-buffer buffer)
896 (kill-buffer buffer))
897 (unless killed
898 (if (server-temp-file-p buffer)
899 (progn
900 (kill-buffer buffer)
901 (setq killed t))
902 (bury-buffer buffer)))))))
903 (list next-buffer killed)))
905 (defun server-temp-file-p (&optional buffer)
906 "Return non-nil if BUFFER contains a file considered temporary.
907 These are files whose names suggest they are repeatedly
908 reused to pass information to another program.
910 The variable `server-temp-file-regexp' controls which filenames
911 are considered temporary."
912 (and (buffer-file-name buffer)
913 (string-match server-temp-file-regexp (buffer-file-name buffer))))
915 (defun server-done ()
916 "Offer to save current buffer, mark it as \"done\" for clients.
917 This kills or buries the buffer, then returns a list
918 of the form (NEXT-BUFFER KILLED). NEXT-BUFFER is another server buffer,
919 as a suggestion for what to select next, or nil.
920 KILLED is t if we killed BUFFER, which happens if it was created
921 specifically for the clients and did not exist before their request for it."
922 (when server-buffer-clients
923 (if (server-temp-file-p)
924 ;; For a temp file, save, and do make a non-numeric backup
925 ;; (unless make-backup-files is nil).
926 (let ((version-control nil)
927 (buffer-backed-up nil))
928 (save-buffer))
929 (if (and (buffer-modified-p)
930 buffer-file-name
931 (y-or-n-p (concat "Save file " buffer-file-name "? ")))
932 (save-buffer)))
933 (server-buffer-done (current-buffer))))
935 ;; Ask before killing a server buffer.
936 ;; It was suggested to release its client instead,
937 ;; but I think that is dangerous--the client would proceed
938 ;; using whatever is on disk in that file. -- rms.
939 (defun server-kill-buffer-query-function ()
940 "Ask before killing a server buffer."
941 (or (not server-buffer-clients)
942 (let ((res t))
943 (dolist (proc server-buffer-clients res)
944 (let ((client (server-client proc)))
945 (when (and client (eq (process-status proc) 'open))
946 (setq res nil)))))
947 (yes-or-no-p (format "Buffer `%s' still has clients; kill it? "
948 (buffer-name (current-buffer))))))
950 (defun server-kill-emacs-query-function ()
951 "Ask before exiting Emacs it has live clients."
952 (or (not server-clients)
953 (let (live-client)
954 (dolist (client server-clients live-client)
955 (if (memq t (mapcar 'buffer-live-p (server-client-get
956 client 'buffers)))
957 (setq live-client t))))
958 (yes-or-no-p "This Emacs session has clients; exit anyway? ")))
960 (defvar server-kill-buffer-running nil
961 "Non-nil while `server-kill-buffer' or `server-buffer-done' is running.")
963 (defun server-kill-buffer ()
964 "Remove the current buffer from its clients' buffer list.
965 Designed to be added to `kill-buffer-hook'."
966 ;; Prevent infinite recursion if user has made server-done-hook
967 ;; call kill-buffer.
968 (or server-kill-buffer-running
969 (and server-buffer-clients
970 (let ((server-kill-buffer-running t))
971 (when server-process
972 (server-buffer-done (current-buffer) t))))))
974 (defun server-edit (&optional arg)
975 "Switch to next server editing buffer; say \"Done\" for current buffer.
976 If a server buffer is current, it is marked \"done\" and optionally saved.
977 The buffer is also killed if it did not exist before the clients asked for it.
978 When all of a client's buffers are marked as \"done\", the client is notified.
980 Temporary files such as MH <draft> files are always saved and backed up,
981 no questions asked. (The variable `make-backup-files', if nil, still
982 inhibits a backup; you can set it locally in a particular buffer to
983 prevent a backup for it.) The variable `server-temp-file-regexp' controls
984 which filenames are considered temporary.
986 If invoked with a prefix argument, or if there is no server process running,
987 starts server process and that is all. Invoked by \\[server-edit]."
988 (interactive "P")
989 (if (or arg
990 (not server-process)
991 (memq (process-status server-process) '(signal exit)))
992 (server-start nil)
993 (apply 'server-switch-buffer (server-done))))
995 (defun server-switch-buffer (&optional next-buffer killed-one)
996 "Switch to another buffer, preferably one that has a client.
997 Arg NEXT-BUFFER is a suggestion; if it is a live buffer, use it.
999 KILLED-ONE is t in a recursive call if we have already killed one
1000 temp-file server buffer. This means we should avoid the final
1001 \"switch to some other buffer\" since we've already effectively
1002 done that."
1003 (if (null next-buffer)
1004 (progn
1005 (let ((rest server-clients))
1006 (while (and rest (not next-buffer))
1007 (let ((client (car rest)))
1008 ;; Only look at frameless clients.
1009 (when (not (server-client-get client 'frame))
1010 (setq next-buffer (car (server-client-get client 'buffers))))
1011 (setq rest (cdr rest)))))
1012 (and next-buffer (server-switch-buffer next-buffer killed-one))
1013 (unless (or next-buffer killed-one (window-dedicated-p (selected-window)))
1014 ;; (switch-to-buffer (other-buffer))
1015 (message "No server buffers remain to edit")))
1016 (if (not (buffer-live-p next-buffer))
1017 ;; If NEXT-BUFFER is a dead buffer, remove the server records for it
1018 ;; and try the next surviving server buffer.
1019 (apply 'server-switch-buffer (server-buffer-done next-buffer))
1020 ;; OK, we know next-buffer is live, let's display and select it.
1021 (if (functionp server-window)
1022 (funcall server-window next-buffer)
1023 (let ((win (get-buffer-window next-buffer 0)))
1024 (if (and win (not server-window))
1025 ;; The buffer is already displayed: just reuse the window.
1026 (let ((frame (window-frame win)))
1027 (if (eq (frame-visible-p frame) 'icon)
1028 (raise-frame frame))
1029 (select-window win)
1030 (set-buffer next-buffer))
1031 ;; Otherwise, let's find an appropriate window.
1032 (cond ((and (windowp server-window)
1033 (window-live-p server-window))
1034 (select-window server-window))
1035 ((framep server-window)
1036 (if (not (frame-live-p server-window))
1037 (setq server-window (make-frame)))
1038 (select-window (frame-selected-window server-window))))
1039 (if (window-minibuffer-p (selected-window))
1040 (select-window (next-window nil 'nomini 0)))
1041 ;; Move to a non-dedicated window, if we have one.
1042 (when (window-dedicated-p (selected-window))
1043 (select-window
1044 (get-window-with-predicate
1045 (lambda (w)
1046 (and (not (window-dedicated-p w))
1047 (equal (frame-terminal (window-frame w))
1048 (frame-terminal (selected-frame)))))
1049 'nomini 'visible (selected-window))))
1050 (condition-case nil
1051 (switch-to-buffer next-buffer)
1052 ;; After all the above, we might still have ended up with
1053 ;; a minibuffer/dedicated-window (if there's no other).
1054 (error (pop-to-buffer next-buffer)))))))))
1056 ;;;###autoload
1057 (defun server-save-buffers-kill-terminal (proc &optional arg)
1058 "Offer to save each buffer, then kill PROC.
1060 With prefix arg, silently save all file-visiting buffers, then kill.
1062 If emacsclient was started with a list of filenames to edit, then
1063 only these files will be asked to be saved."
1064 (let ((buffers (server-client-get proc 'buffers)))
1065 ;; If client is bufferless, emulate a normal Emacs session
1066 ;; exit and offer to save all buffers. Otherwise, offer to
1067 ;; save only the buffers belonging to the client.
1068 (save-some-buffers arg
1069 (if buffers
1070 (lambda () (memq (current-buffer) buffers))
1072 (server-delete-client proc)))
1074 (define-key ctl-x-map "#" 'server-edit)
1076 (defun server-unload-hook ()
1077 "Unload the server library."
1078 (server-start t)
1079 (remove-hook 'suspend-tty-functions 'server-handle-suspend-tty)
1080 (remove-hook 'delete-frame-functions 'server-handle-delete-frame)
1081 (remove-hook 'kill-buffer-query-functions 'server-kill-buffer-query-function)
1082 (remove-hook 'kill-emacs-query-functions 'server-kill-emacs-query-function)
1083 (remove-hook 'kill-buffer-hook 'server-kill-buffer))
1085 (add-hook 'server-unload-hook 'server-unload-hook)
1087 (provide 'server)
1089 ;;; arch-tag: 1f7ecb42-f00a-49f8-906d-61995d84c8d6
1090 ;;; server.el ends here