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[emacs.git] / lisp / server.el
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1 ;;; server.el --- Lisp code for GNU Emacs running as server process -*- lexical-binding: t -*-
3 ;; Copyright (C) 1986-1987, 1992, 1994-2015 Free Software Foundation,
4 ;; Inc.
6 ;; Author: William Sommerfeld <wesommer@athena.mit.edu>
7 ;; Maintainer: emacs-devel@gnu.org
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 3 of the License, or
18 ;; (at your option) 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. If not, see <http://www.gnu.org/licenses/>.
28 ;;; Commentary:
30 ;; This Lisp code is run in Emacs when it is to operate as
31 ;; a server for other processes.
33 ;; Load this library and do M-x server-edit to enable Emacs as a server.
34 ;; Emacs opens up a socket for communication with clients. If there are no
35 ;; client buffers to edit, server-edit acts like (switch-to-buffer
36 ;; (other-buffer))
38 ;; When some other program runs "the editor" to edit a file,
39 ;; "the editor" can be the Emacs client program ../lib-src/emacsclient.
40 ;; This program transmits the file names to Emacs through
41 ;; the server subprocess, and Emacs visits them and lets you edit them.
43 ;; Note that any number of clients may dispatch files to Emacs to be edited.
45 ;; When you finish editing a Server buffer, again call server-edit
46 ;; to mark that buffer as done for the client and switch to the next
47 ;; Server buffer. When all the buffers for a client have been edited
48 ;; and exited with server-edit, the client "editor" will return
49 ;; to the program that invoked it.
51 ;; Your editing commands and Emacs's display output go to and from
52 ;; the terminal in the usual way. Thus, server operation is possible
53 ;; only when Emacs can talk to the terminal at the time you invoke
54 ;; the client. This is possible in four cases:
56 ;; 1. On a window system, where Emacs runs in one window and the
57 ;; program that wants to use "the editor" runs in another.
59 ;; 2. On a multi-terminal system, where Emacs runs on one terminal and the
60 ;; program that wants to use "the editor" runs on another.
62 ;; 3. When the program that wants to use "the editor" is running
63 ;; as a subprocess of Emacs.
65 ;; 4. On a system with job control, when Emacs is suspended, the program
66 ;; that wants to use "the editor" will stop and display
67 ;; "Waiting for Emacs...". It can then be suspended, and Emacs can be
68 ;; brought into the foreground for editing. When done editing, Emacs is
69 ;; suspended again, and the client program is brought into the foreground.
71 ;; The buffer local variable "server-buffer-clients" lists
72 ;; the clients who are waiting for this buffer to be edited.
73 ;; The global variable "server-clients" lists all the waiting clients,
74 ;; and which files are yet to be edited for each.
76 ;; Todo:
78 ;; - handle command-line-args-left.
79 ;; - move most of the args processing and decision making from emacsclient.c
80 ;; to here.
81 ;; - fix up handling of the client's environment (place it in the terminal?).
83 ;;; Code:
85 (eval-when-compile (require 'cl-lib))
87 (defgroup server nil
88 "Emacs running as a server process."
89 :group 'external)
91 (defcustom server-use-tcp nil
92 "If non-nil, use TCP sockets instead of local sockets."
93 :set #'(lambda (sym val)
94 (unless (featurep 'make-network-process '(:family local))
95 (setq val t)
96 (unless load-in-progress
97 (message "Local sockets unsupported, using TCP sockets")))
98 (set-default sym val))
99 :group 'server
100 :type 'boolean
101 :version "22.1")
103 (defcustom server-host nil
104 "The name or IP address to use as host address of the server process.
105 If set, the server accepts remote connections; otherwise it is local.
107 DO NOT give this a non-nil value unless you know what you are doing!
108 On unsecured networks, accepting remote connections is very dangerous,
109 because server-client communication (including session authentication)
110 is not encrypted."
111 :group 'server
112 :type '(choice
113 (string :tag "Name or IP address")
114 (const :tag "Local" nil))
115 :version "22.1")
116 ;;;###autoload
117 (put 'server-host 'risky-local-variable t)
119 (defcustom server-port nil
120 "The port number that the server process should listen on.
121 This variable only takes effect when the Emacs server is using
122 TCP instead of local sockets. A nil value means to use a random
123 port number."
124 :group 'server
125 :type '(choice
126 (string :tag "Port number")
127 (const :tag "Random" nil))
128 :version "24.1")
129 ;;;###autoload
130 (put 'server-port 'risky-local-variable t)
132 (defcustom server-auth-dir (locate-user-emacs-file "server/")
133 "Directory for server authentication files.
134 We only use this if `server-use-tcp' is non-nil.
135 Otherwise we use `server-socket-dir'.
137 NOTE: On FAT32 filesystems, directories are not secure;
138 files can be read and modified by any user or process.
139 It is strongly suggested to set `server-auth-dir' to a
140 directory residing in a NTFS partition instead."
141 :group 'server
142 :type 'directory
143 :version "22.1")
144 ;;;###autoload
145 (put 'server-auth-dir 'risky-local-variable t)
147 (defcustom server-auth-key nil
148 "Server authentication key.
149 This is only used if `server-use-tcp' is non-nil.
151 Normally, the authentication key is randomly generated when the
152 server starts. It is recommended to leave it that way. Using a
153 long-lived shared key will decrease security (especially since
154 the key is transmitted as plain-text).
156 In some situations however, it can be difficult to share randomly
157 generated passwords with remote hosts (e.g., no shared directory),
158 so you can set the key with this variable and then copy the
159 server file to the remote host (with possible changes to IP
160 address and/or port if that applies).
162 Note that the usual security risks of using the server over
163 remote TCP, arising from the fact that client-server
164 communications are unencrypted, still apply.
166 The key must consist of 64 ASCII printable characters except for
167 space (this means characters from ! to ~; or from code 33 to
168 126). You can use \\[server-generate-key] to get a random key."
169 :group 'server
170 :type '(choice
171 (const :tag "Random" nil)
172 (string :tag "Password"))
173 :version "24.3")
175 (defcustom server-raise-frame t
176 "If non-nil, raise frame when switching to a buffer."
177 :group 'server
178 :type 'boolean
179 :version "22.1")
181 (defcustom server-visit-hook nil
182 "Hook run when visiting a file for the Emacs server."
183 :group 'server
184 :type 'hook)
186 (defcustom server-switch-hook nil
187 "Hook run when switching to a buffer for the Emacs server."
188 :group 'server
189 :type 'hook)
191 (defcustom server-done-hook nil
192 "Hook run when done editing a buffer for the Emacs server."
193 :group 'server
194 :type 'hook)
196 (defvar server-process nil
197 "The current server process.")
199 (defvar server-clients nil
200 "List of current server clients.
201 Each element is a process.")
203 (defvar server-buffer-clients nil
204 "List of client processes requesting editing of current buffer.")
205 (make-variable-buffer-local 'server-buffer-clients)
206 ;; Changing major modes should not erase this local.
207 (put 'server-buffer-clients 'permanent-local t)
209 (defcustom server-window nil
210 "Specification of the window to use for selecting Emacs server buffers.
211 If nil, use the selected window.
212 If it is a function, it should take one argument (a buffer) and
213 display and select it. A common value is `pop-to-buffer'.
214 If it is a window, use that.
215 If it is a frame, use the frame's selected window.
217 It is not meaningful to set this to a specific frame or window with Custom.
218 Only programs can do so."
219 :group 'server
220 :version "22.1"
221 :type '(choice (const :tag "Use selected window"
222 :match (lambda (widget value)
223 (not (functionp value)))
224 nil)
225 (function-item :tag "Display in new frame" switch-to-buffer-other-frame)
226 (function-item :tag "Use pop-to-buffer" pop-to-buffer)
227 (function :tag "Other function")))
229 (defcustom server-temp-file-regexp "^/tmp/Re\\|/draft$"
230 "Regexp matching names of temporary files.
231 These are deleted and reused after each edit by the programs that
232 invoke the Emacs server."
233 :group 'server
234 :type 'regexp)
236 (defcustom server-kill-new-buffers t
237 "Whether to kill buffers when done with them.
238 If non-nil, kill a buffer unless it already existed before editing
239 it with the Emacs server. If nil, kill only buffers as specified by
240 `server-temp-file-regexp'.
241 Please note that only buffers that still have a client are killed,
242 i.e. buffers visited with \"emacsclient --no-wait\" are never killed
243 in this way."
244 :group 'server
245 :type 'boolean
246 :version "21.1")
248 ;; FIXME? This is not a minor mode; what's the point of this? (See bug#20201)
249 (or (assq 'server-buffer-clients minor-mode-alist)
250 (push '(server-buffer-clients " Server") minor-mode-alist))
252 (defvar server-existing-buffer nil
253 "Non-nil means the buffer existed before the server was asked to visit it.
254 This means that the server should not kill the buffer when you say you
255 are done with it in the server.")
256 (make-variable-buffer-local 'server-existing-buffer)
258 (defcustom server-name "server"
259 "The name of the Emacs server, if this Emacs process creates one.
260 The command `server-start' makes use of this. It should not be
261 changed while a server is running."
262 :group 'server
263 :type 'string
264 :version "23.1")
266 ;; We do not use `temporary-file-directory' here, because emacsclient
267 ;; does not read the init file.
268 (defvar server-socket-dir
269 (and (featurep 'make-network-process '(:family local))
270 (format "%s/emacs%d" (or (getenv "TMPDIR") "/tmp") (user-uid)))
271 "The directory in which to place the server socket.
272 If local sockets are not supported, this is nil.")
274 (defun server-clients-with (property value)
275 "Return a list of clients with PROPERTY set to VALUE."
276 (let (result)
277 (dolist (proc server-clients)
278 (when (equal value (process-get proc property))
279 (push proc result)))
280 result))
282 (defun server-add-client (proc)
283 "Create a client for process PROC, if it doesn't already have one.
284 New clients have no properties."
285 (add-to-list 'server-clients proc))
287 (defmacro server-with-environment (env vars &rest body)
288 "Evaluate BODY with environment variables VARS set to those in ENV.
289 The environment variables are then restored to their previous values.
291 VARS should be a list of strings.
292 ENV should be in the same format as `process-environment'."
293 (declare (indent 2))
294 (let ((var (make-symbol "var"))
295 (value (make-symbol "value")))
296 `(let ((process-environment process-environment))
297 (dolist (,var ,vars)
298 (let ((,value (getenv-internal ,var ,env)))
299 (push (if (stringp ,value)
300 (concat ,var "=" ,value)
301 ,var)
302 process-environment)))
303 (progn ,@body))))
305 (defun server-delete-client (proc &optional noframe)
306 "Delete PROC, including its buffers, terminals and frames.
307 If NOFRAME is non-nil, let the frames live.
308 Updates `server-clients'."
309 (server-log (concat "server-delete-client" (if noframe " noframe")) proc)
310 ;; Force a new lookup of client (prevents infinite recursion).
311 (when (memq proc server-clients)
312 (let ((buffers (process-get proc 'buffers)))
314 ;; Kill the client's buffers.
315 (dolist (buf buffers)
316 (when (buffer-live-p buf)
317 (with-current-buffer buf
318 ;; Kill the buffer if necessary.
319 (when (and (equal server-buffer-clients
320 (list proc))
321 (or (and server-kill-new-buffers
322 (not server-existing-buffer))
323 (server-temp-file-p))
324 (not (buffer-modified-p)))
325 (let (flag)
326 (unwind-protect
327 (progn (setq server-buffer-clients nil)
328 (kill-buffer (current-buffer))
329 (setq flag t))
330 (unless flag
331 ;; Restore clients if user pressed C-g in `kill-buffer'.
332 (setq server-buffer-clients (list proc)))))))))
334 ;; Delete the client's frames.
335 (unless noframe
336 (dolist (frame (frame-list))
337 (when (and (frame-live-p frame)
338 (equal proc (frame-parameter frame 'client)))
339 ;; Prevent `server-handle-delete-frame' from calling us
340 ;; recursively.
341 (set-frame-parameter frame 'client nil)
342 (delete-frame frame))))
344 (setq server-clients (delq proc server-clients))
346 ;; Delete the client's tty, except on Windows (both GUI and console),
347 ;; where there's only one terminal and does not make sense to delete it.
348 (unless (eq system-type 'windows-nt)
349 (let ((terminal (process-get proc 'terminal)))
350 ;; Only delete the terminal if it is non-nil.
351 (when (and terminal (eq (terminal-live-p terminal) t))
352 (delete-terminal terminal))))
354 ;; Delete the client's process.
355 (if (eq (process-status proc) 'open)
356 (delete-process proc))
358 (server-log "Deleted" proc))))
360 (defvar server-log-time-function 'current-time-string
361 "Function to generate timestamps for `server-buffer'.")
363 (defconst server-buffer " *server*"
364 "Buffer used internally by Emacs's server.
365 One use is to log the I/O for debugging purposes (see option `server-log'),
366 the other is to provide a current buffer in which the process filter can
367 safely let-bind buffer-local variables like `default-directory'.")
369 (defvar server-log nil
370 "If non-nil, log the server's inputs and outputs in the `server-buffer'.")
372 (defun server-log (string &optional client)
373 "If option `server-log' is non-nil, log STRING to `server-buffer'.
374 If CLIENT is non-nil, add a description of it to the logged message."
375 (when server-log
376 (with-current-buffer (get-buffer-create server-buffer)
377 (goto-char (point-max))
378 (insert (funcall server-log-time-function)
379 (cond
380 ((null client) " ")
381 ((listp client) (format " %s: " (car client)))
382 (t (format " %s: " client)))
383 string)
384 (or (bolp) (newline)))))
386 (defun server-sentinel (proc msg)
387 "The process sentinel for Emacs server connections."
388 ;; If this is a new client process, set the query-on-exit flag to nil
389 ;; for this process (it isn't inherited from the server process).
390 (when (and (eq (process-status proc) 'open)
391 (process-query-on-exit-flag proc))
392 (set-process-query-on-exit-flag proc nil))
393 ;; Delete the associated connection file, if applicable.
394 ;; Although there's no 100% guarantee that the file is owned by the
395 ;; running Emacs instance, server-start uses server-running-p to check
396 ;; for possible servers before doing anything, so it *should* be ours.
397 (and (process-contact proc :server)
398 (eq (process-status proc) 'closed)
399 (ignore-errors
400 (delete-file (process-get proc :server-file))))
401 (server-log (format "Status changed to %s: %s" (process-status proc) msg) proc)
402 (server-delete-client proc))
404 (defun server--on-display-p (frame display)
405 (and (equal (frame-parameter frame 'display) display)
406 ;; Note: TTY frames still get a `display' parameter set to the value of
407 ;; $DISPLAY. This is useful when running from that tty frame
408 ;; sub-processes that want to connect to the X server, but that means we
409 ;; have to be careful here not to be tricked into thinking those frames
410 ;; are on `display'.
411 (not (eq (framep frame) t))))
413 (defun server-select-display (display)
414 ;; If the current frame is on `display' we're all set.
415 ;; Similarly if we are unable to open frames on other displays, there's
416 ;; nothing more we can do.
417 (unless (or (not (fboundp 'make-frame-on-display))
418 (server--on-display-p (selected-frame) display))
419 ;; Otherwise, look for an existing frame there and select it.
420 (dolist (frame (frame-list))
421 (when (server--on-display-p frame display)
422 (select-frame frame)))
423 ;; If there's no frame on that display yet, create and select one.
424 (unless (server--on-display-p (selected-frame) display)
425 (let* ((buffer (generate-new-buffer " *server-dummy*"))
426 (frame (make-frame-on-display
427 display
428 ;; Make it display (and remember) some dummy buffer, so
429 ;; we can detect later if the frame is in use or not.
430 `((server-dummy-buffer . ,buffer)
431 ;; This frame may be deleted later (see
432 ;; server-unselect-display) so we want it to be as
433 ;; unobtrusive as possible.
434 (visibility . nil)))))
435 (select-frame frame)
436 (set-window-buffer (selected-window) buffer)
437 frame))))
439 (defun server-unselect-display (frame)
440 (when (frame-live-p frame)
441 ;; If the temporary frame is in use (displays something real), make it
442 ;; visible. If not (which can happen if the user's customizations call
443 ;; pop-to-buffer etc.), delete it to avoid preserving the connection after
444 ;; the last real frame is deleted.
446 ;; Rewritten to avoid inadvertently killing the current buffer after
447 ;; `delete-frame' removed FRAME (Bug#10729).
448 (let ((buffer (frame-parameter frame 'server-dummy-buffer)))
449 (if (and (one-window-p 'nomini frame)
450 (eq (window-buffer (frame-first-window frame)) buffer))
451 ;; The temp frame still only shows one buffer, and that is the
452 ;; internal temp buffer.
453 (delete-frame frame)
454 (set-frame-parameter frame 'visibility t)
455 (set-frame-parameter frame 'server-dummy-buffer nil))
456 (when (buffer-live-p buffer)
457 (kill-buffer buffer)))))
459 (defun server-handle-delete-frame (frame)
460 "Delete the client connection when the emacsclient frame is deleted.
461 \(To be used from `delete-frame-functions'.)"
462 (let ((proc (frame-parameter frame 'client)))
463 (when (and (frame-live-p frame)
464 proc
465 ;; See if this is the last frame for this client.
466 (>= 1 (let ((frame-num 0))
467 (dolist (f (frame-list))
468 (when (eq proc (frame-parameter f 'client))
469 (setq frame-num (1+ frame-num))))
470 frame-num)))
471 (server-log (format "server-handle-delete-frame, frame %s" frame) proc)
472 (server-delete-client proc 'noframe)))) ; Let delete-frame delete the frame later.
474 (defun server-handle-suspend-tty (terminal)
475 "Notify the client process that its tty device is suspended."
476 (dolist (proc (server-clients-with 'terminal terminal))
477 (server-log (format "server-handle-suspend-tty, terminal %s" terminal)
478 proc)
479 (condition-case nil
480 (server-send-string proc "-suspend \n")
481 (file-error ;The pipe/socket was closed.
482 (ignore-errors (server-delete-client proc))))))
484 (defun server-unquote-arg (arg)
485 "Remove &-quotation from ARG.
486 See `server-quote-arg' and `server-process-filter'."
487 (replace-regexp-in-string
488 "&." (lambda (s)
489 (pcase (aref s 1)
490 (?& "&")
491 (?- "-")
492 (?n "\n")
493 (_ " ")))
494 arg t t))
496 (defun server-quote-arg (arg)
497 "In ARG, insert a & before each &, each space, each newline, and -.
498 Change spaces to underscores, too, so that the return value never
499 contains a space.
501 See `server-unquote-arg' and `server-process-filter'."
502 (replace-regexp-in-string
503 "[-&\n ]" (lambda (s)
504 (pcase (aref s 0)
505 (?& "&&")
506 (?- "&-")
507 (?\n "&n")
508 (?\s "&_")))
509 arg t t))
511 (defun server-send-string (proc string)
512 "A wrapper around `process-send-string' for logging."
513 (server-log (concat "Sent " string) proc)
514 (process-send-string proc string))
516 (defun server-ensure-safe-dir (dir)
517 "Make sure DIR is a directory with no race-condition issues.
518 Creates the directory if necessary and makes sure:
519 - there's no symlink involved
520 - it's owned by us
521 - it's not readable/writable by anybody else."
522 (setq dir (directory-file-name dir))
523 (let ((attrs (file-attributes dir 'integer)))
524 (unless attrs
525 (cl-letf (((default-file-modes) ?\700)) (make-directory dir t))
526 (setq attrs (file-attributes dir 'integer)))
528 ;; Check that it's safe for use.
529 (let* ((uid (nth 2 attrs))
530 (w32 (eq system-type 'windows-nt))
531 (safe (cond
532 ((not (eq t (car attrs))) nil) ; is a dir?
533 ((and w32 (zerop uid)) ; on FAT32?
534 (display-warning
535 'server
536 (format "Using `%s' to store Emacs-server authentication files.
537 Directories on FAT32 filesystems are NOT secure against tampering.
538 See variable `server-auth-dir' for details."
539 (file-name-as-directory dir))
540 :warning)
542 ((and (/= uid (user-uid)) ; is the dir ours?
543 (or (not w32)
544 ;; Files created on Windows by Administrator
545 ;; (RID=500) have the Administrators (RID=544)
546 ;; group recorded as the owner.
547 (/= uid 544) (/= (user-uid) 500)))
548 nil)
549 (w32 t) ; on NTFS?
550 (t ; else, check permissions
551 (zerop (logand ?\077 (file-modes dir)))))))
552 (unless safe
553 (error "The directory `%s' is unsafe" dir)))))
555 (defun server-generate-key ()
556 "Generate and return a random authentication key.
557 The key is a 64-byte string of random chars in the range `!'..`~'.
558 If called interactively, also inserts it into current buffer."
559 (interactive)
560 (let ((auth-key
561 (cl-loop repeat 64
562 collect (+ 33 (random 94)) into auth
563 finally return (concat auth))))
564 (if (called-interactively-p 'interactive)
565 (insert auth-key))
566 auth-key))
568 (defun server-get-auth-key ()
569 "Return server's authentication key.
571 If `server-auth-key' is nil, just call `server-generate-key'.
572 Otherwise, if `server-auth-key' is a valid key, return it.
573 If the key is not valid, signal an error."
574 (if server-auth-key
575 (if (string-match-p "^[!-~]\\{64\\}$" server-auth-key)
576 server-auth-key
577 (error "The key ‘%s’ is invalid" server-auth-key))
578 (server-generate-key)))
580 ;;;###autoload
581 (defun server-start (&optional leave-dead inhibit-prompt)
582 "Allow this Emacs process to be a server for client processes.
583 This starts a server communications subprocess through which client
584 \"editors\" can send your editing commands to this Emacs job.
585 To use the server, set up the program `emacsclient' in the Emacs
586 distribution as your standard \"editor\".
588 Optional argument LEAVE-DEAD (interactively, a prefix arg) means just
589 kill any existing server communications subprocess.
591 If a server is already running, restart it. If clients are
592 running, ask the user for confirmation first, unless optional
593 argument INHIBIT-PROMPT is non-nil.
595 To force-start a server, do \\[server-force-delete] and then
596 \\[server-start]."
597 (interactive "P")
598 (when (or (not server-clients)
599 ;; Ask the user before deleting existing clients---except
600 ;; when we can't get user input, which may happen when
601 ;; doing emacsclient --eval "(kill-emacs)" in daemon mode.
602 (cond
603 ((and (daemonp)
604 (null (cdr (frame-list)))
605 (eq (selected-frame) terminal-frame))
606 leave-dead)
607 (inhibit-prompt t)
608 (t (yes-or-no-p
609 "The current server still has clients; delete them? "))))
610 (let* ((server-dir (if server-use-tcp server-auth-dir server-socket-dir))
611 (server-file (expand-file-name server-name server-dir)))
612 (when server-process
613 ;; kill it dead!
614 (ignore-errors (delete-process server-process)))
615 ;; Delete the socket files made by previous server invocations.
616 (if (not (eq t (server-running-p server-name)))
617 ;; Remove any leftover socket or authentication file
618 (ignore-errors
619 (let (delete-by-moving-to-trash)
620 (delete-file server-file)))
621 (setq server-mode nil) ;; already set by the minor mode code
622 (display-warning
623 'server
624 (concat "Unable to start the Emacs server.\n"
625 (format "There is an existing Emacs server, named %S.\n"
626 server-name)
627 (substitute-command-keys
628 "To start the server in this Emacs process, stop the existing
629 server or call `\\[server-force-delete]' to forcibly disconnect it."))
630 :warning)
631 (setq leave-dead t))
632 ;; If this Emacs already had a server, clear out associated status.
633 (while server-clients
634 (server-delete-client (car server-clients)))
635 ;; Now any previous server is properly stopped.
636 (if leave-dead
637 (progn
638 (unless (eq t leave-dead) (server-log (message "Server stopped")))
639 (setq server-process nil))
640 ;; Make sure there is a safe directory in which to place the socket.
641 (server-ensure-safe-dir server-dir)
642 (when server-process
643 (server-log (message "Restarting server")))
644 (cl-letf (((default-file-modes) ?\700))
645 (add-hook 'suspend-tty-functions 'server-handle-suspend-tty)
646 (add-hook 'delete-frame-functions 'server-handle-delete-frame)
647 (add-hook 'kill-emacs-query-functions
648 'server-kill-emacs-query-function)
649 (add-hook 'kill-emacs-hook 'server-force-stop) ;Cleanup upon exit.
650 (setq server-process
651 (apply #'make-network-process
652 :name server-name
653 :server t
654 :noquery t
655 :sentinel #'server-sentinel
656 :filter #'server-process-filter
657 ;; We must receive file names without being decoded.
658 ;; Those are decoded by server-process-filter according
659 ;; to file-name-coding-system. Also don't get
660 ;; confused by CRs since we don't quote them.
661 :coding 'raw-text-unix
662 ;; The other args depend on the kind of socket used.
663 (if server-use-tcp
664 (list :family 'ipv4 ;; We're not ready for IPv6 yet
665 :service (or server-port t)
666 :host (or server-host 'local)
667 :plist '(:authenticated nil))
668 (list :family 'local
669 :service server-file
670 :plist '(:authenticated t)))))
671 (unless server-process (error "Could not start server process"))
672 (process-put server-process :server-file server-file)
673 (when server-use-tcp
674 (let ((auth-key (server-get-auth-key)))
675 (process-put server-process :auth-key auth-key)
676 (with-temp-file server-file
677 (set-buffer-multibyte nil)
678 (setq buffer-file-coding-system 'no-conversion)
679 (insert (format-network-address
680 (process-contact server-process :local))
681 " " (number-to-string (emacs-pid)) ; Kept for compatibility
682 "\n" auth-key)))))))))
684 (defun server-force-stop ()
685 "Kill all connections to the current server.
686 This function is meant to be called from `kill-emacs-hook'."
687 (server-start t t))
689 ;;;###autoload
690 (defun server-force-delete (&optional name)
691 "Unconditionally delete connection file for server NAME.
692 If server is running, it is first stopped.
693 NAME defaults to `server-name'. With argument, ask for NAME."
694 (interactive
695 (list (if current-prefix-arg
696 (read-string "Server name: " nil nil server-name))))
697 (when server-mode (with-temp-message nil (server-mode -1)))
698 (let ((file (expand-file-name (or name server-name)
699 (if server-use-tcp
700 server-auth-dir
701 server-socket-dir))))
702 (condition-case nil
703 (let (delete-by-moving-to-trash)
704 (delete-file file)
705 (message "Connection file %S deleted" file))
706 (file-error
707 (message "No connection file %S" file)))))
709 (defun server-running-p (&optional name)
710 "Test whether server NAME is running.
712 Return values:
713 nil the server is definitely not running.
714 t the server seems to be running.
715 something else we cannot determine whether it's running without using
716 commands which may have to wait for a long time."
717 (unless name (setq name server-name))
718 (condition-case nil
719 (if server-use-tcp
720 (with-temp-buffer
721 (insert-file-contents-literally (expand-file-name name server-auth-dir))
722 (or (and (looking-at "127\\.0\\.0\\.1:[0-9]+ \\([0-9]+\\)")
723 (assq 'comm
724 (process-attributes
725 (string-to-number (match-string 1))))
727 :other))
728 (delete-process
729 (make-network-process
730 :name "server-client-test" :family 'local :server nil :noquery t
731 :service (expand-file-name name server-socket-dir)))
733 (file-error nil)))
735 ;;;###autoload
736 (define-minor-mode server-mode
737 "Toggle Server mode.
738 With a prefix argument ARG, enable Server mode if ARG is
739 positive, and disable it otherwise. If called from Lisp, enable
740 Server mode if ARG is omitted or nil.
742 Server mode runs a process that accepts commands from the
743 `emacsclient' program. See Info node `Emacs server' and
744 `server-start' for details."
745 :global t
746 :group 'server
747 :version "22.1"
748 ;; Fixme: Should this check for an existing server socket and do
749 ;; nothing if there is one (for multiple Emacs sessions)?
750 (server-start (not server-mode)))
752 (defun server-eval-and-print (expr proc)
753 "Eval EXPR and send the result back to client PROC."
754 ;; While we're running asynchronously (from a process filter), it is likely
755 ;; that the emacsclient command was run in response to a user
756 ;; action, so the user probably knows that Emacs is processing this
757 ;; emacsclient request, so if we get a C-g it's likely that the user
758 ;; intended it to interrupt us rather than interrupt whatever Emacs
759 ;; was doing before it started handling the process filter.
760 ;; Hence `with-local-quit' (bug#6585).
761 (let ((v (with-local-quit (eval (car (read-from-string expr))))))
762 (when proc
763 (with-temp-buffer
764 (let ((standard-output (current-buffer)))
765 (pp v)
766 (let ((text (buffer-substring-no-properties
767 (point-min) (point-max))))
768 (server-reply-print (server-quote-arg text) proc)))))))
770 (defconst server-msg-size 1024
771 "Maximum size of a message sent to a client.")
773 (defun server-reply-print (qtext proc)
774 "Send a `-print QTEXT' command to client PROC.
775 QTEXT must be already quoted.
776 This handles splitting the command if it would be bigger than
777 `server-msg-size'."
778 (let ((prefix "-print ")
779 part)
780 (while (> (+ (length qtext) (length prefix) 1) server-msg-size)
781 ;; We have to split the string
782 (setq part (substring qtext 0 (- server-msg-size (length prefix) 1)))
783 ;; Don't split in the middle of a quote sequence
784 (if (string-match "\\(^\\|[^&]\\)\\(&&\\)+$" part)
785 ;; There is an uneven number of & at the end
786 (setq part (substring part 0 -1)))
787 (setq qtext (substring qtext (length part)))
788 (server-send-string proc (concat prefix part "\n"))
789 (setq prefix "-print-nonl "))
790 (server-send-string proc (concat prefix qtext "\n"))))
792 (defun server-create-tty-frame (tty type proc)
793 (unless tty
794 (error "Invalid terminal device"))
795 (unless type
796 (error "Invalid terminal type"))
797 (add-to-list 'frame-inherited-parameters 'client)
798 (let ((frame
799 (server-with-environment
800 (process-get proc 'env)
801 '("LANG" "LC_CTYPE" "LC_ALL"
802 ;; For tgetent(3); list according to ncurses(3).
803 "BAUDRATE" "COLUMNS" "ESCDELAY" "HOME" "LINES"
804 "NCURSES_ASSUMED_COLORS" "NCURSES_NO_PADDING"
805 "NCURSES_NO_SETBUF" "TERM" "TERMCAP" "TERMINFO"
806 "TERMINFO_DIRS" "TERMPATH"
807 ;; rxvt wants these
808 "COLORFGBG" "COLORTERM")
809 (make-frame `((window-system . nil)
810 (tty . ,tty)
811 (tty-type . ,type)
812 ;; Ignore nowait here; we always need to
813 ;; clean up opened ttys when the client dies.
814 (client . ,proc)
815 ;; This is a leftover from an earlier
816 ;; attempt at making it possible for process
817 ;; run in the server process to use the
818 ;; environment of the client process.
819 ;; It has no effect now and to make it work
820 ;; we'd need to decide how to make
821 ;; process-environment interact with client
822 ;; envvars, and then to change the
823 ;; C functions `child_setup' and
824 ;; `getenv_internal' accordingly.
825 (environment . ,(process-get proc 'env)))))))
827 ;; ttys don't use the `display' parameter, but callproc.c does to set
828 ;; the DISPLAY environment on subprocesses.
829 (set-frame-parameter frame 'display
830 (getenv-internal "DISPLAY" (process-get proc 'env)))
831 (select-frame frame)
832 (process-put proc 'frame frame)
833 (process-put proc 'terminal (frame-terminal frame))
834 frame))
836 (defun server-create-window-system-frame (display nowait proc parent-id
837 &optional parameters)
838 (let* ((display (or display
839 (frame-parameter nil 'display)
840 (error "Please specify display.")))
841 (w (or (cdr (assq 'window-system parameters))
842 (window-system-for-display display))))
844 ;; Special case for ns. This is because DISPLAY may not be set at all
845 ;; which in the ns case isn't an error. The variable display then becomes
846 ;; the fully qualified hostname, which make-frame-on-display below
847 ;; does not understand and throws an error.
848 ;; It may also be a valid X display, but if Emacs is compiled for ns, it
849 ;; can not make X frames.
850 (if (featurep 'ns-win)
851 (setq w 'ns display "ns")
852 ;; FIXME! Not sure what this was for, and not sure how it should work
853 ;; in the cl-defmethod new world!
854 ;;(unless (assq w window-system-initialization-alist)
855 ;; (setq w nil))
858 (cond (w
859 ;; Flag frame as client-created, but use a dummy client.
860 ;; This will prevent the frame from being deleted when
861 ;; emacsclient quits while also preventing
862 ;; `server-save-buffers-kill-terminal' from unexpectedly
863 ;; killing emacs on that frame.
864 (let* ((params `((client . ,(if nowait 'nowait proc))
865 ;; This is a leftover, see above.
866 (environment . ,(process-get proc 'env))
867 ,@parameters))
868 frame)
869 (if parent-id
870 (push (cons 'parent-id (string-to-number parent-id)) params))
871 (add-to-list 'frame-inherited-parameters 'client)
872 (setq frame (make-frame-on-display display params))
873 (server-log (format "%s created" frame) proc)
874 (select-frame frame)
875 (process-put proc 'frame frame)
876 (process-put proc 'terminal (frame-terminal frame))
877 frame))
880 (server-log "Window system unsupported" proc)
881 (server-send-string proc "-window-system-unsupported \n")
882 nil))))
884 (defun server-goto-toplevel (proc)
885 (condition-case nil
886 ;; If we're running isearch, we must abort it to allow Emacs to
887 ;; display the buffer and switch to it.
888 (dolist (buffer (buffer-list))
889 (with-current-buffer buffer
890 (when (bound-and-true-p isearch-mode)
891 (isearch-cancel))))
892 ;; Signaled by isearch-cancel.
893 (quit (message nil)))
894 (when (> (recursion-depth) 0)
895 ;; We're inside a minibuffer already, so if the emacs-client is trying
896 ;; to open a frame on a new display, we might end up with an unusable
897 ;; frame because input from that display will be blocked (until exiting
898 ;; the minibuffer). Better exit this minibuffer right away.
899 ;; Similarly with recursive-edits such as the splash screen.
900 (run-with-timer 0 nil (lambda () (server-execute-continuation proc)))
901 (top-level)))
903 ;; We use various special properties on process objects:
904 ;; - `env' stores the info about the environment of the emacsclient process.
905 ;; - `continuation' is a no-arg function that we need to execute. It contains
906 ;; commands we wanted to execute in some earlier invocation of the process
907 ;; filter but that we somehow were unable to process at that time
908 ;; (e.g. because we first need to throw to the toplevel).
910 (defun server-execute-continuation (proc)
911 (let ((continuation (process-get proc 'continuation)))
912 (process-put proc 'continuation nil)
913 (if continuation (ignore-errors (funcall continuation)))))
915 (cl-defun server-process-filter (proc string)
916 "Process a request from the server to edit some files.
917 PROC is the server process. STRING consists of a sequence of
918 commands prefixed by a dash. Some commands have arguments;
919 these are &-quoted and need to be decoded by `server-unquote-arg'.
920 The filter parses and executes these commands.
922 To illustrate the protocol, here is an example command that
923 emacsclient sends to create a new X frame (note that the whole
924 sequence is sent on a single line):
926 -env HOME=/home/lorentey
927 -env DISPLAY=:0.0
928 ... lots of other -env commands
929 -display :0.0
930 -window-system
932 The following commands are accepted by the server:
934 `-auth AUTH-STRING'
935 Authenticate the client using the secret authentication string
936 AUTH-STRING.
938 `-env NAME=VALUE'
939 An environment variable on the client side.
941 `-dir DIRNAME'
942 The current working directory of the client process.
944 `-current-frame'
945 Forbid the creation of new frames.
947 `-frame-parameters ALIST'
948 Set the parameters of the created frame.
950 `-nowait'
951 Request that the next frame created should not be
952 associated with this client.
954 `-display DISPLAY'
955 Set the display name to open X frames on.
957 `-position LINE[:COLUMN]'
958 Go to the given line and column number
959 in the next file opened.
961 `-file FILENAME'
962 Load the given file in the current frame.
964 `-eval EXPR'
965 Evaluate EXPR as a Lisp expression and return the
966 result in -print commands.
968 `-window-system'
969 Open a new X frame.
971 `-tty DEVICENAME TYPE'
972 Open a new tty frame at the client.
974 `-suspend'
975 Suspend this tty frame. The client sends this string in
976 response to SIGTSTP and SIGTTOU. The server must cease all I/O
977 on this tty until it gets a -resume command.
979 `-resume'
980 Resume this tty frame. The client sends this string when it
981 gets the SIGCONT signal and it is the foreground process on its
982 controlling tty.
984 `-ignore COMMENT'
985 Do nothing, but put the comment in the server log.
986 Useful for debugging.
989 The following commands are accepted by the client:
991 `-emacs-pid PID'
992 Describes the process id of the Emacs process;
993 used to forward window change signals to it.
995 `-window-system-unsupported'
996 Signals that the server does not support creating X frames;
997 the client must try again with a tty frame.
999 `-print STRING'
1000 Print STRING on stdout. Used to send values
1001 returned by -eval.
1003 `-print-nonl STRING'
1004 Print STRING on stdout. Used to continue a
1005 preceding -print command that would be too big to send
1006 in a single message.
1008 `-error DESCRIPTION'
1009 Signal an error and delete process PROC.
1011 `-suspend'
1012 Suspend this terminal, i.e., stop the client process.
1013 Sent when the user presses C-z."
1014 (server-log (concat "Received " string) proc)
1015 ;; First things first: let's check the authentication
1016 (unless (process-get proc :authenticated)
1017 (if (and (string-match "-auth \\([!-~]+\\)\n?" string)
1018 (equal (match-string 1 string) (process-get proc :auth-key)))
1019 (progn
1020 (setq string (substring string (match-end 0)))
1021 (process-put proc :authenticated t)
1022 (server-log "Authentication successful" proc))
1023 (server-log "Authentication failed" proc)
1024 (server-send-string
1025 proc (concat "-error " (server-quote-arg "Authentication failed")))
1026 ;; Before calling `delete-process', give emacsclient time to
1027 ;; receive the error string and shut down on its own.
1028 (sit-for 1)
1029 (delete-process proc)
1030 ;; We return immediately.
1031 (cl-return-from server-process-filter)))
1032 (let ((prev (process-get proc 'previous-string)))
1033 (when prev
1034 (setq string (concat prev string))
1035 (process-put proc 'previous-string nil)))
1036 (condition-case err
1037 (progn
1038 (server-add-client proc)
1039 ;; Send our pid
1040 (server-send-string proc (concat "-emacs-pid "
1041 (number-to-string (emacs-pid)) "\n"))
1042 (if (not (string-match "\n" string))
1043 ;; Save for later any partial line that remains.
1044 (when (> (length string) 0)
1045 (process-put proc 'previous-string string))
1047 ;; In earlier versions of server.el (where we used an `emacsserver'
1048 ;; process), there could be multiple lines. Nowadays this is not
1049 ;; supported any more.
1050 (cl-assert (eq (match-end 0) (length string)))
1051 (let ((request (substring string 0 (match-beginning 0)))
1052 (coding-system (and (default-value 'enable-multibyte-characters)
1053 (or file-name-coding-system
1054 default-file-name-coding-system)))
1055 nowait ; t if emacsclient does not want to wait for us.
1056 frame ; Frame opened for the client (if any).
1057 display ; Open frame on this display.
1058 parent-id ; Window ID for XEmbed
1059 dontkill ; t if client should not be killed.
1060 commands
1062 use-current-frame
1063 frame-parameters ;parameters for newly created frame
1064 tty-name ; nil, `window-system', or the tty name.
1065 tty-type ; string.
1066 files
1067 filepos
1068 args-left)
1069 ;; Remove this line from STRING.
1070 (setq string (substring string (match-end 0)))
1071 (setq args-left
1072 (mapcar 'server-unquote-arg (split-string request " " t)))
1073 (while args-left
1074 (pcase (pop args-left)
1075 ;; -version CLIENT-VERSION: obsolete at birth.
1076 (`"-version" (pop args-left))
1078 ;; -nowait: Emacsclient won't wait for a result.
1079 (`"-nowait" (setq nowait t))
1081 ;; -current-frame: Don't create frames.
1082 (`"-current-frame" (setq use-current-frame t))
1084 ;; -frame-parameters: Set frame parameters
1085 (`"-frame-parameters"
1086 (let ((alist (pop args-left)))
1087 (if coding-system
1088 (setq alist (decode-coding-string alist coding-system)))
1089 (setq frame-parameters (car (read-from-string alist)))))
1091 ;; -display DISPLAY:
1092 ;; Open X frames on the given display instead of the default.
1093 (`"-display"
1094 (setq display (pop args-left))
1095 (if (zerop (length display)) (setq display nil)))
1097 ;; -parent-id ID:
1098 ;; Open X frame within window ID, via XEmbed.
1099 (`"-parent-id"
1100 (setq parent-id (pop args-left))
1101 (if (zerop (length parent-id)) (setq parent-id nil)))
1103 ;; -window-system: Open a new X frame.
1104 (`"-window-system"
1105 (if (fboundp 'x-create-frame)
1106 (setq dontkill t
1107 tty-name 'window-system)))
1109 ;; -resume: Resume a suspended tty frame.
1110 (`"-resume"
1111 (let ((terminal (process-get proc 'terminal)))
1112 (setq dontkill t)
1113 (push (lambda ()
1114 (when (eq (terminal-live-p terminal) t)
1115 (resume-tty terminal)))
1116 commands)))
1118 ;; -suspend: Suspend the client's frame. (In case we
1119 ;; get out of sync, and a C-z sends a SIGTSTP to
1120 ;; emacsclient.)
1121 (`"-suspend"
1122 (let ((terminal (process-get proc 'terminal)))
1123 (setq dontkill t)
1124 (push (lambda ()
1125 (when (eq (terminal-live-p terminal) t)
1126 (suspend-tty terminal)))
1127 commands)))
1129 ;; -ignore COMMENT: Noop; useful for debugging emacsclient.
1130 ;; (The given comment appears in the server log.)
1131 (`"-ignore"
1132 (setq dontkill t)
1133 (pop args-left))
1135 ;; -tty DEVICE-NAME TYPE: Open a new tty frame.
1136 ;; (But if we see -window-system later, use that.)
1137 (`"-tty"
1138 (setq tty-name (pop args-left)
1139 tty-type (pop args-left)
1140 dontkill (or dontkill
1141 (not use-current-frame)))
1142 ;; On Windows, emacsclient always asks for a tty
1143 ;; frame. If running a GUI server, force the frame
1144 ;; type to GUI. (Cygwin is perfectly happy with
1145 ;; multi-tty support, so don't override the user's
1146 ;; choice there.) In daemon mode on Windows, we can't
1147 ;; make tty frames, so force the frame type to GUI
1148 ;; there too.
1149 (when (and (eq system-type 'windows-nt)
1150 (or (daemonp)
1151 (eq window-system 'w32)))
1152 (push "-window-system" args-left)))
1154 ;; -position LINE[:COLUMN]: Set point to the given
1155 ;; position in the next file.
1156 (`"-position"
1157 (if (not (string-match "\\+\\([0-9]+\\)\\(?::\\([0-9]+\\)\\)?"
1158 (car args-left)))
1159 (error "Invalid -position command in client args"))
1160 (let ((arg (pop args-left)))
1161 (setq filepos
1162 (cons (string-to-number (match-string 1 arg))
1163 (string-to-number (or (match-string 2 arg)
1164 ""))))))
1166 ;; -file FILENAME: Load the given file.
1167 (`"-file"
1168 (let ((file (pop args-left)))
1169 (if coding-system
1170 (setq file (decode-coding-string file coding-system)))
1171 ;; Allow Cygwin's emacsclient to be used as a file
1172 ;; handler on MS-Windows, in which case FILENAME
1173 ;; might start with a drive letter.
1174 (when (and (eq system-type 'cygwin)
1175 (string-match "\\`[A-Za-z]:" file))
1176 (setq file (cygwin-convert-file-name-from-windows file)))
1177 (setq file (expand-file-name file dir))
1178 (push (cons file filepos) files)
1179 (server-log (format "New file: %s %s"
1180 file (or filepos ""))
1181 proc))
1182 (setq filepos nil))
1184 ;; -eval EXPR: Evaluate a Lisp expression.
1185 (`"-eval"
1186 (if use-current-frame
1187 (setq use-current-frame 'always))
1188 (let ((expr (pop args-left)))
1189 (if coding-system
1190 (setq expr (decode-coding-string expr coding-system)))
1191 (push (lambda () (server-eval-and-print expr proc))
1192 commands)
1193 (setq filepos nil)))
1195 ;; -env NAME=VALUE: An environment variable.
1196 (`"-env"
1197 (let ((var (pop args-left)))
1198 ;; XXX Variables should be encoded as in getenv/setenv.
1199 (process-put proc 'env
1200 (cons var (process-get proc 'env)))))
1202 ;; -dir DIRNAME: The cwd of the emacsclient process.
1203 (`"-dir"
1204 (setq dir (pop args-left))
1205 (if coding-system
1206 (setq dir (decode-coding-string dir coding-system)))
1207 (setq dir (command-line-normalize-file-name dir))
1208 (process-put proc 'server-client-directory dir))
1210 ;; Unknown command.
1211 (arg (error "Unknown command: %s" arg))))
1213 ;; If both -no-wait and -tty are given with file or sexp
1214 ;; arguments, use an existing frame.
1215 (and nowait
1216 (not (eq tty-name 'window-system))
1217 (or files commands)
1218 (setq use-current-frame t))
1220 (setq frame
1221 (cond
1222 ((and use-current-frame
1223 (or (eq use-current-frame 'always)
1224 ;; We can't use the Emacs daemon's
1225 ;; terminal frame.
1226 (not (and (daemonp)
1227 (null (cdr (frame-list)))
1228 (eq (selected-frame)
1229 terminal-frame)))))
1230 (setq tty-name nil tty-type nil)
1231 (if display (server-select-display display)))
1232 ((or (and (eq system-type 'windows-nt)
1233 (daemonp)
1234 (setq display "w32"))
1235 (eq tty-name 'window-system))
1236 (server-create-window-system-frame display nowait proc
1237 parent-id
1238 frame-parameters))
1239 ;; When resuming on a tty, tty-name is nil.
1240 (tty-name
1241 (server-create-tty-frame tty-name tty-type proc))))
1243 (process-put
1244 proc 'continuation
1245 (lambda ()
1246 (with-current-buffer (get-buffer-create server-buffer)
1247 ;; Use the same cwd as the emacsclient, if possible, so
1248 ;; relative file names work correctly, even in `eval'.
1249 (let ((default-directory
1250 (if (and dir (file-directory-p dir))
1251 dir default-directory)))
1252 (server-execute proc files nowait commands
1253 dontkill frame tty-name)))))
1255 (when (or frame files)
1256 (server-goto-toplevel proc))
1258 (server-execute-continuation proc))))
1259 ;; condition-case
1260 (error (server-return-error proc err))))
1262 (defun server-execute (proc files nowait commands dontkill frame tty-name)
1263 ;; This is run from timers and process-filters, i.e. "asynchronously".
1264 ;; But w.r.t the user, this is not really asynchronous since the timer
1265 ;; is run after 0s and the process-filter is run in response to the
1266 ;; user running `emacsclient'. So it is OK to override the
1267 ;; inhibit-quit flag, which is good since `commands' (as well as
1268 ;; find-file-noselect via the major-mode) can run arbitrary code,
1269 ;; including code that needs to wait.
1270 (with-local-quit
1271 (condition-case err
1272 (let ((buffers (server-visit-files files proc nowait)))
1273 (mapc 'funcall (nreverse commands))
1275 ;; If we were told only to open a new client, obey
1276 ;; `initial-buffer-choice' if it specifies a file
1277 ;; or a function.
1278 (unless (or files commands)
1279 (let ((buf
1280 (cond ((stringp initial-buffer-choice)
1281 (find-file-noselect initial-buffer-choice))
1282 ((functionp initial-buffer-choice)
1283 (funcall initial-buffer-choice)))))
1284 (switch-to-buffer
1285 (if (buffer-live-p buf) buf (get-buffer-create "*scratch*"))
1286 'norecord)))
1288 ;; Delete the client if necessary.
1289 (cond
1290 (nowait
1291 ;; Client requested nowait; return immediately.
1292 (server-log "Close nowait client" proc)
1293 (server-delete-client proc))
1294 ((and (not dontkill) (null buffers))
1295 ;; This client is empty; get rid of it immediately.
1296 (server-log "Close empty client" proc)
1297 (server-delete-client proc)))
1298 (cond
1299 ((or isearch-mode (minibufferp))
1300 nil)
1301 ((and frame (null buffers))
1302 (message "%s" (substitute-command-keys
1303 "When done with this frame, type \\[delete-frame]")))
1304 ((not (null buffers))
1305 (server-switch-buffer (car buffers) nil (cdr (car files)))
1306 (run-hooks 'server-switch-hook)
1307 (unless nowait
1308 (message "%s" (substitute-command-keys
1309 "When done with a buffer, type \\[server-edit]")))))
1310 (when (and frame (null tty-name))
1311 (server-unselect-display frame)))
1312 ((quit error)
1313 (when (eq (car err) 'quit)
1314 (message "Quit emacsclient request"))
1315 (server-return-error proc err)))))
1317 (defun server-return-error (proc err)
1318 (ignore-errors
1319 (server-send-string
1320 proc (concat "-error " (server-quote-arg
1321 (error-message-string err))))
1322 (server-log (error-message-string err) proc)
1323 ;; Before calling `delete-process', give emacsclient time to
1324 ;; receive the error string and shut down on its own.
1325 (sit-for 5)
1326 (delete-process proc)))
1328 (defun server-goto-line-column (line-col)
1329 "Move point to the position indicated in LINE-COL.
1330 LINE-COL should be a pair (LINE . COL)."
1331 (when line-col
1332 (goto-char (point-min))
1333 (forward-line (1- (car line-col)))
1334 (let ((column-number (cdr line-col)))
1335 (when (> column-number 0)
1336 (move-to-column (1- column-number))))))
1338 (defun server-visit-files (files proc &optional nowait)
1339 "Find FILES and return a list of buffers created.
1340 FILES is an alist whose elements are (FILENAME . FILEPOS)
1341 where FILEPOS can be nil or a pair (LINENUMBER . COLUMNNUMBER).
1342 PROC is the client that requested this operation.
1343 NOWAIT non-nil means this client is not waiting for the results,
1344 so don't mark these buffers specially, just visit them normally."
1345 ;; Bind last-nonmenu-event to force use of keyboard, not mouse, for queries.
1346 (let ((last-nonmenu-event t) client-record)
1347 ;; Restore the current buffer afterward, but not using save-excursion,
1348 ;; because we don't want to save point in this buffer
1349 ;; if it happens to be one of those specified by the server.
1350 (save-current-buffer
1351 (dolist (file files)
1352 ;; If there is an existing buffer modified or the file is
1353 ;; modified, revert it. If there is an existing buffer with
1354 ;; deleted file, offer to write it.
1355 (let* ((minibuffer-auto-raise (or server-raise-frame
1356 minibuffer-auto-raise))
1357 (filen (car file))
1358 (obuf (get-file-buffer filen)))
1359 (add-to-history 'file-name-history filen)
1360 (if (null obuf)
1361 (progn
1362 (run-hooks 'pre-command-hook)
1363 (set-buffer (find-file-noselect filen)))
1364 (set-buffer obuf)
1365 ;; separately for each file, in sync with post-command hooks,
1366 ;; with the new buffer current:
1367 (run-hooks 'pre-command-hook)
1368 (cond ((file-exists-p filen)
1369 (when (not (verify-visited-file-modtime obuf))
1370 (revert-buffer t nil)))
1372 (when (y-or-n-p
1373 (concat "File no longer exists: " filen
1374 ", write buffer to file? "))
1375 (write-file filen))))
1376 (unless server-buffer-clients
1377 (setq server-existing-buffer t)))
1378 (server-goto-line-column (cdr file))
1379 (run-hooks 'server-visit-hook)
1380 ;; hooks may be specific to current buffer:
1381 (run-hooks 'post-command-hook))
1382 (unless nowait
1383 ;; When the buffer is killed, inform the clients.
1384 (add-hook 'kill-buffer-hook 'server-kill-buffer nil t)
1385 (push proc server-buffer-clients))
1386 (push (current-buffer) client-record)))
1387 (unless nowait
1388 (process-put proc 'buffers
1389 (nconc (process-get proc 'buffers) client-record)))
1390 client-record))
1392 (defvar server-kill-buffer-running nil
1393 "Non-nil while `server-kill-buffer' or `server-buffer-done' is running.")
1395 (defun server-buffer-done (buffer &optional for-killing)
1396 "Mark BUFFER as \"done\" for its client(s).
1397 This buries the buffer, then returns a list of the form (NEXT-BUFFER KILLED).
1398 NEXT-BUFFER is another server buffer, as a suggestion for what to select next,
1399 or nil. KILLED is t if we killed BUFFER (typically, because it was visiting
1400 a temp file).
1401 FOR-KILLING if non-nil indicates that we are called from `kill-buffer'."
1402 (let ((next-buffer nil)
1403 (killed nil))
1404 (dolist (proc server-clients)
1405 (let ((buffers (process-get proc 'buffers)))
1406 (or next-buffer
1407 (setq next-buffer (nth 1 (memq buffer buffers))))
1408 (when buffers ; Ignore bufferless clients.
1409 (setq buffers (delq buffer buffers))
1410 ;; Delete all dead buffers from PROC.
1411 (dolist (b buffers)
1412 (and (bufferp b)
1413 (not (buffer-live-p b))
1414 (setq buffers (delq b buffers))))
1415 (process-put proc 'buffers buffers)
1416 ;; If client now has no pending buffers,
1417 ;; tell it that it is done, and forget it entirely.
1418 (unless buffers
1419 (server-log "Close" proc)
1420 (if for-killing
1421 ;; `server-delete-client' might delete the client's
1422 ;; frames, which might change the current buffer. We
1423 ;; don't want that (bug#640).
1424 (save-current-buffer
1425 (server-delete-client proc))
1426 (server-delete-client proc))))))
1427 (when (and (bufferp buffer) (buffer-name buffer))
1428 ;; We may or may not kill this buffer;
1429 ;; if we do, do not call server-buffer-done recursively
1430 ;; from kill-buffer-hook.
1431 (let ((server-kill-buffer-running t))
1432 (with-current-buffer buffer
1433 (setq server-buffer-clients nil)
1434 (run-hooks 'server-done-hook))
1435 ;; Notice whether server-done-hook killed the buffer.
1436 (if (null (buffer-name buffer))
1437 (setq killed t)
1438 ;; Don't bother killing or burying the buffer
1439 ;; when we are called from kill-buffer.
1440 (unless for-killing
1441 (when (and (not killed)
1442 server-kill-new-buffers
1443 (with-current-buffer buffer
1444 (not server-existing-buffer)))
1445 (setq killed t)
1446 (bury-buffer buffer)
1447 ;; Prevent kill-buffer from prompting (Bug#3696).
1448 (with-current-buffer buffer
1449 (set-buffer-modified-p nil))
1450 (kill-buffer buffer))
1451 (unless killed
1452 (if (server-temp-file-p buffer)
1453 (progn
1454 (with-current-buffer buffer
1455 (set-buffer-modified-p nil))
1456 (kill-buffer buffer)
1457 (setq killed t))
1458 (bury-buffer buffer)))))))
1459 (list next-buffer killed)))
1461 (defun server-temp-file-p (&optional buffer)
1462 "Return non-nil if BUFFER contains a file considered temporary.
1463 These are files whose names suggest they are repeatedly
1464 reused to pass information to another program.
1466 The variable `server-temp-file-regexp' controls which filenames
1467 are considered temporary."
1468 (and (buffer-file-name buffer)
1469 (string-match-p server-temp-file-regexp (buffer-file-name buffer))))
1471 (defun server-done ()
1472 "Offer to save current buffer, mark it as \"done\" for clients.
1473 This kills or buries the buffer, then returns a list
1474 of the form (NEXT-BUFFER KILLED). NEXT-BUFFER is another server buffer,
1475 as a suggestion for what to select next, or nil.
1476 KILLED is t if we killed BUFFER, which happens if it was created
1477 specifically for the clients and did not exist before their request for it."
1478 (when server-buffer-clients
1479 (if (server-temp-file-p)
1480 ;; For a temp file, save, and do make a non-numeric backup
1481 ;; (unless make-backup-files is nil).
1482 (let ((version-control nil)
1483 (buffer-backed-up nil))
1484 (save-buffer))
1485 (when (and (buffer-modified-p)
1486 buffer-file-name
1487 (y-or-n-p (concat "Save file " buffer-file-name "? ")))
1488 (save-buffer)))
1489 (server-buffer-done (current-buffer))))
1491 (defun server-kill-emacs-query-function ()
1492 "Ask before exiting Emacs if it has live clients."
1493 (or (not server-clients)
1494 (let (live-client)
1495 (dolist (proc server-clients)
1496 (when (memq t (mapcar 'buffer-live-p (process-get
1497 proc 'buffers)))
1498 (setq live-client t)))
1499 live-client)
1500 (yes-or-no-p "This Emacs session has clients; exit anyway? ")))
1502 (defun server-kill-buffer ()
1503 "Remove the current buffer from its clients' buffer list.
1504 Designed to be added to `kill-buffer-hook'."
1505 ;; Prevent infinite recursion if user has made server-done-hook
1506 ;; call kill-buffer.
1507 (or server-kill-buffer-running
1508 (and server-buffer-clients
1509 (let ((server-kill-buffer-running t))
1510 (when server-process
1511 (server-buffer-done (current-buffer) t))))))
1513 (defun server-edit (&optional arg)
1514 "Switch to next server editing buffer; say \"Done\" for current buffer.
1515 If a server buffer is current, it is marked \"done\" and optionally saved.
1516 The buffer is also killed if it did not exist before the clients asked for it.
1517 When all of a client's buffers are marked as \"done\", the client is notified.
1519 Temporary files such as MH <draft> files are always saved and backed up,
1520 no questions asked. (The variable `make-backup-files', if nil, still
1521 inhibits a backup; you can set it locally in a particular buffer to
1522 prevent a backup for it.) The variable `server-temp-file-regexp' controls
1523 which filenames are considered temporary.
1525 If invoked with a prefix argument, or if there is no server process running,
1526 starts server process and that is all. Invoked by \\[server-edit]."
1527 (interactive "P")
1528 (cond
1529 ((or arg
1530 (not server-process)
1531 (memq (process-status server-process) '(signal exit)))
1532 (server-mode 1))
1533 (server-clients (apply 'server-switch-buffer (server-done)))
1534 (t (message "No server editing buffers exist"))))
1536 (defun server-switch-buffer (&optional next-buffer killed-one filepos)
1537 "Switch to another buffer, preferably one that has a client.
1538 Arg NEXT-BUFFER is a suggestion; if it is a live buffer, use it.
1540 KILLED-ONE is t in a recursive call if we have already killed one
1541 temp-file server buffer. This means we should avoid the final
1542 \"switch to some other buffer\" since we've already effectively
1543 done that.
1545 FILEPOS specifies a new buffer position for NEXT-BUFFER, if we
1546 visit NEXT-BUFFER in an existing window. If non-nil, it should
1547 be a cons cell (LINENUMBER . COLUMNNUMBER)."
1548 (if (null next-buffer)
1549 (progn
1550 (let ((rest server-clients))
1551 (while (and rest (not next-buffer))
1552 (let ((proc (car rest)))
1553 ;; Only look at frameless clients, or those in the selected
1554 ;; frame.
1555 (when (or (not (process-get proc 'frame))
1556 (eq (process-get proc 'frame) (selected-frame)))
1557 (setq next-buffer (car (process-get proc 'buffers))))
1558 (setq rest (cdr rest)))))
1559 (and next-buffer (server-switch-buffer next-buffer killed-one))
1560 (unless (or next-buffer killed-one (window-dedicated-p))
1561 ;; (switch-to-buffer (other-buffer))
1562 (message "No server buffers remain to edit")))
1563 (if (not (buffer-live-p next-buffer))
1564 ;; If NEXT-BUFFER is a dead buffer, remove the server records for it
1565 ;; and try the next surviving server buffer.
1566 (apply 'server-switch-buffer (server-buffer-done next-buffer))
1567 ;; OK, we know next-buffer is live, let's display and select it.
1568 (if (functionp server-window)
1569 (funcall server-window next-buffer)
1570 (let ((win (get-buffer-window next-buffer 0)))
1571 (if (and win (not server-window))
1572 ;; The buffer is already displayed: just reuse the
1573 ;; window. If FILEPOS is non-nil, use it to replace the
1574 ;; window's own value of point.
1575 (progn
1576 (select-window win)
1577 (set-buffer next-buffer)
1578 (when filepos
1579 (server-goto-line-column filepos)))
1580 ;; Otherwise, let's find an appropriate window.
1581 (cond ((window-live-p server-window)
1582 (select-window server-window))
1583 ((framep server-window)
1584 (unless (frame-live-p server-window)
1585 (setq server-window (make-frame)))
1586 (select-window (frame-selected-window server-window))))
1587 (when (window-minibuffer-p)
1588 (select-window (next-window nil 'nomini 0)))
1589 ;; Move to a non-dedicated window, if we have one.
1590 (when (window-dedicated-p)
1591 (select-window
1592 (get-window-with-predicate
1593 (lambda (w)
1594 (and (not (window-dedicated-p w))
1595 (equal (frame-terminal (window-frame w))
1596 (frame-terminal))))
1597 'nomini 'visible (selected-window))))
1598 (condition-case nil
1599 (switch-to-buffer next-buffer)
1600 ;; After all the above, we might still have ended up with
1601 ;; a minibuffer/dedicated-window (if there's no other).
1602 (error (pop-to-buffer next-buffer)))))))
1603 (when server-raise-frame
1604 (select-frame-set-input-focus (window-frame)))))
1606 ;;;###autoload
1607 (defun server-save-buffers-kill-terminal (arg)
1608 ;; Called from save-buffers-kill-terminal in files.el.
1609 "Offer to save each buffer, then kill the current client.
1610 With ARG non-nil, silently save all file-visiting buffers, then kill.
1612 If emacsclient was started with a list of filenames to edit, then
1613 only these files will be asked to be saved."
1614 (let ((proc (frame-parameter nil 'client)))
1615 (cond ((eq proc 'nowait)
1616 ;; Nowait frames have no client buffer list.
1617 (if (cdr (frame-list))
1618 (progn (save-some-buffers arg)
1619 (delete-frame))
1620 ;; If we're the last frame standing, kill Emacs.
1621 (save-buffers-kill-emacs arg)))
1622 ((processp proc)
1623 (let ((buffers (process-get proc 'buffers)))
1624 ;; If client is bufferless, emulate a normal Emacs exit
1625 ;; and offer to save all buffers. Otherwise, offer to
1626 ;; save only the buffers belonging to the client.
1627 (save-some-buffers
1628 arg (if buffers
1629 (lambda () (memq (current-buffer) buffers))
1631 (server-delete-client proc)))
1632 (t (error "Invalid client frame")))))
1634 (define-key ctl-x-map "#" 'server-edit)
1636 (defun server-unload-function ()
1637 "Unload the Server library."
1638 (server-mode -1)
1639 (substitute-key-definition 'server-edit nil ctl-x-map)
1640 (save-current-buffer
1641 (dolist (buffer (buffer-list))
1642 (set-buffer buffer)
1643 (remove-hook 'kill-buffer-hook 'server-kill-buffer t)))
1644 ;; continue standard unloading
1645 nil)
1647 (defun server-eval-at (server form)
1648 "Contact the Emacs server named SERVER and evaluate FORM there.
1649 Returns the result of the evaluation, or signals an error if it
1650 cannot contact the specified server. For example:
1651 (server-eval-at \"server\" '(emacs-pid))
1652 returns the process ID of the Emacs instance running \"server\"."
1653 (let* ((server-dir (if server-use-tcp server-auth-dir server-socket-dir))
1654 (server-file (expand-file-name server server-dir))
1655 (coding-system-for-read 'binary)
1656 (coding-system-for-write 'binary)
1657 address port secret process)
1658 (unless (file-exists-p server-file)
1659 (error "No such server: %s" server))
1660 (with-temp-buffer
1661 (when server-use-tcp
1662 (let ((coding-system-for-read 'no-conversion))
1663 (insert-file-contents server-file)
1664 (unless (looking-at "\\([0-9.]+\\):\\([0-9]+\\)")
1665 (error "Invalid auth file"))
1666 (setq address (match-string 1)
1667 port (string-to-number (match-string 2)))
1668 (forward-line 1)
1669 (setq secret (buffer-substring (point) (line-end-position)))
1670 (erase-buffer)))
1671 (unless (setq process (make-network-process
1672 :name "eval-at"
1673 :buffer (current-buffer)
1674 :host address
1675 :service (if server-use-tcp port server-file)
1676 :family (if server-use-tcp 'ipv4 'local)
1677 :noquery t))
1678 (error "Unable to contact the server"))
1679 (if server-use-tcp
1680 (process-send-string process (concat "-auth " secret "\n")))
1681 (process-send-string process
1682 (concat "-eval "
1683 (server-quote-arg (format "%S" form))
1684 "\n"))
1685 (while (memq (process-status process) '(open run))
1686 (accept-process-output process 0 10))
1687 (goto-char (point-min))
1688 ;; If the result is nil, there's nothing in the buffer. If the
1689 ;; result is non-nil, it's after "-print ".
1690 (let ((answer ""))
1691 (while (re-search-forward "\n-print\\(-nonl\\)? " nil t)
1692 (setq answer
1693 (concat answer
1694 (buffer-substring (point)
1695 (progn (skip-chars-forward "^\n")
1696 (point))))))
1697 (if (not (equal answer ""))
1698 (read (decode-coding-string (server-unquote-arg answer)
1699 'emacs-internal)))))))
1702 (provide 'server)
1704 ;;; server.el ends here