* doc/lispref/frames.texi (Mouse Tracking): Fix typo.
[emacs.git] / lisp / server.el
blobb16a06e79f0c26d90632d3418fcc0dd8508fc97e
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-message "\
537 Using `%s' to store Emacs-server authentication files.
538 Directories on FAT32 filesystems are NOT secure against tampering.
539 See variable `server-auth-dir' for details."
540 (file-name-as-directory dir))
541 :warning)
543 ((and (/= uid (user-uid)) ; is the dir ours?
544 (or (not w32)
545 ;; Files created on Windows by Administrator
546 ;; (RID=500) have the Administrators (RID=544)
547 ;; group recorded as the owner.
548 (/= uid 544) (/= (user-uid) 500)))
549 nil)
550 (w32 t) ; on NTFS?
551 (t ; else, check permissions
552 (zerop (logand ?\077 (file-modes dir)))))))
553 (unless safe
554 (error "The directory `%s' is unsafe" dir)))))
556 (defun server-generate-key ()
557 "Generate and return a random authentication key.
558 The key is a 64-byte string of random chars in the range `!'..`~'.
559 If called interactively, also inserts it into current buffer."
560 (interactive)
561 (let ((auth-key
562 (cl-loop repeat 64
563 collect (+ 33 (random 94)) into auth
564 finally return (concat auth))))
565 (if (called-interactively-p 'interactive)
566 (insert auth-key))
567 auth-key))
569 (defun server-get-auth-key ()
570 "Return server's authentication key.
572 If `server-auth-key' is nil, just call `server-generate-key'.
573 Otherwise, if `server-auth-key' is a valid key, return it.
574 If the key is not valid, signal an error."
575 (if server-auth-key
576 (if (string-match-p "^[!-~]\\{64\\}$" server-auth-key)
577 server-auth-key
578 (error "The key ‘%s’ is invalid" server-auth-key))
579 (server-generate-key)))
581 ;;;###autoload
582 (defun server-start (&optional leave-dead inhibit-prompt)
583 "Allow this Emacs process to be a server for client processes.
584 This starts a server communications subprocess through which client
585 \"editors\" can send your editing commands to this Emacs job.
586 To use the server, set up the program `emacsclient' in the Emacs
587 distribution as your standard \"editor\".
589 Optional argument LEAVE-DEAD (interactively, a prefix arg) means just
590 kill any existing server communications subprocess.
592 If a server is already running, restart it. If clients are
593 running, ask the user for confirmation first, unless optional
594 argument INHIBIT-PROMPT is non-nil.
596 To force-start a server, do \\[server-force-delete] and then
597 \\[server-start]."
598 (interactive "P")
599 (when (or (not server-clients)
600 ;; Ask the user before deleting existing clients---except
601 ;; when we can't get user input, which may happen when
602 ;; doing emacsclient --eval "(kill-emacs)" in daemon mode.
603 (cond
604 ((and (daemonp)
605 (null (cdr (frame-list)))
606 (eq (selected-frame) terminal-frame))
607 leave-dead)
608 (inhibit-prompt t)
609 (t (yes-or-no-p
610 "The current server still has clients; delete them? "))))
611 (let* ((server-dir (if server-use-tcp server-auth-dir server-socket-dir))
612 (server-file (expand-file-name server-name server-dir)))
613 (when server-process
614 ;; kill it dead!
615 (ignore-errors (delete-process server-process)))
616 ;; Delete the socket files made by previous server invocations.
617 (if (not (eq t (server-running-p server-name)))
618 ;; Remove any leftover socket or authentication file
619 (ignore-errors
620 (let (delete-by-moving-to-trash)
621 (delete-file server-file)))
622 (setq server-mode nil) ;; already set by the minor mode code
623 (display-warning
624 'server
625 (concat "Unable to start the Emacs server.\n"
626 (format "There is an existing Emacs server, named %S.\n"
627 server-name)
628 (substitute-command-keys
629 "To start the server in this Emacs process, stop the existing
630 server or call `\\[server-force-delete]' to forcibly disconnect it."))
631 :warning)
632 (setq leave-dead t))
633 ;; If this Emacs already had a server, clear out associated status.
634 (while server-clients
635 (server-delete-client (car server-clients)))
636 ;; Now any previous server is properly stopped.
637 (if leave-dead
638 (progn
639 (unless (eq t leave-dead) (server-log (message "Server stopped")))
640 (setq server-process nil))
641 ;; Make sure there is a safe directory in which to place the socket.
642 (server-ensure-safe-dir server-dir)
643 (when server-process
644 (server-log (message "Restarting server")))
645 (cl-letf (((default-file-modes) ?\700))
646 (add-hook 'suspend-tty-functions 'server-handle-suspend-tty)
647 (add-hook 'delete-frame-functions 'server-handle-delete-frame)
648 (add-hook 'kill-emacs-query-functions
649 'server-kill-emacs-query-function)
650 (add-hook 'kill-emacs-hook 'server-force-stop) ;Cleanup upon exit.
651 (setq server-process
652 (apply #'make-network-process
653 :name server-name
654 :server t
655 :noquery t
656 :sentinel #'server-sentinel
657 :filter #'server-process-filter
658 ;; We must receive file names without being decoded.
659 ;; Those are decoded by server-process-filter according
660 ;; to file-name-coding-system. Also don't get
661 ;; confused by CRs since we don't quote them.
662 :coding 'raw-text-unix
663 ;; The other args depend on the kind of socket used.
664 (if server-use-tcp
665 (list :family 'ipv4 ;; We're not ready for IPv6 yet
666 :service (or server-port t)
667 :host (or server-host 'local)
668 :plist '(:authenticated nil))
669 (list :family 'local
670 :service server-file
671 :plist '(:authenticated t)))))
672 (unless server-process (error "Could not start server process"))
673 (process-put server-process :server-file server-file)
674 (when server-use-tcp
675 (let ((auth-key (server-get-auth-key)))
676 (process-put server-process :auth-key auth-key)
677 (with-temp-file server-file
678 (set-buffer-multibyte nil)
679 (setq buffer-file-coding-system 'no-conversion)
680 (insert (format-network-address
681 (process-contact server-process :local))
682 " " (number-to-string (emacs-pid)) ; Kept for compatibility
683 "\n" auth-key)))))))))
685 (defun server-force-stop ()
686 "Kill all connections to the current server.
687 This function is meant to be called from `kill-emacs-hook'."
688 (server-start t t))
690 ;;;###autoload
691 (defun server-force-delete (&optional name)
692 "Unconditionally delete connection file for server NAME.
693 If server is running, it is first stopped.
694 NAME defaults to `server-name'. With argument, ask for NAME."
695 (interactive
696 (list (if current-prefix-arg
697 (read-string "Server name: " nil nil server-name))))
698 (when server-mode (with-temp-message nil (server-mode -1)))
699 (let ((file (expand-file-name (or name server-name)
700 (if server-use-tcp
701 server-auth-dir
702 server-socket-dir))))
703 (condition-case nil
704 (let (delete-by-moving-to-trash)
705 (delete-file file)
706 (message "Connection file %S deleted" file))
707 (file-error
708 (message "No connection file %S" file)))))
710 (defun server-running-p (&optional name)
711 "Test whether server NAME is running.
713 Return values:
714 nil the server is definitely not running.
715 t the server seems to be running.
716 something else we cannot determine whether it's running without using
717 commands which may have to wait for a long time."
718 (unless name (setq name server-name))
719 (condition-case nil
720 (if server-use-tcp
721 (with-temp-buffer
722 (insert-file-contents-literally (expand-file-name name server-auth-dir))
723 (or (and (looking-at "127\\.0\\.0\\.1:[0-9]+ \\([0-9]+\\)")
724 (assq 'comm
725 (process-attributes
726 (string-to-number (match-string 1))))
728 :other))
729 (delete-process
730 (make-network-process
731 :name "server-client-test" :family 'local :server nil :noquery t
732 :service (expand-file-name name server-socket-dir)))
734 (file-error nil)))
736 ;;;###autoload
737 (define-minor-mode server-mode
738 "Toggle Server mode.
739 With a prefix argument ARG, enable Server mode if ARG is
740 positive, and disable it otherwise. If called from Lisp, enable
741 Server mode if ARG is omitted or nil.
743 Server mode runs a process that accepts commands from the
744 `emacsclient' program. See Info node `Emacs server' and
745 `server-start' for details."
746 :global t
747 :group 'server
748 :version "22.1"
749 ;; Fixme: Should this check for an existing server socket and do
750 ;; nothing if there is one (for multiple Emacs sessions)?
751 (server-start (not server-mode)))
753 (defun server-eval-and-print (expr proc)
754 "Eval EXPR and send the result back to client PROC."
755 ;; While we're running asynchronously (from a process filter), it is likely
756 ;; that the emacsclient command was run in response to a user
757 ;; action, so the user probably knows that Emacs is processing this
758 ;; emacsclient request, so if we get a C-g it's likely that the user
759 ;; intended it to interrupt us rather than interrupt whatever Emacs
760 ;; was doing before it started handling the process filter.
761 ;; Hence `with-local-quit' (bug#6585).
762 (let ((v (with-local-quit (eval (car (read-from-string expr))))))
763 (when proc
764 (with-temp-buffer
765 (let ((standard-output (current-buffer)))
766 (pp v)
767 (let ((text (buffer-substring-no-properties
768 (point-min) (point-max))))
769 (server-reply-print (server-quote-arg text) proc)))))))
771 (defconst server-msg-size 1024
772 "Maximum size of a message sent to a client.")
774 (defun server-reply-print (qtext proc)
775 "Send a `-print QTEXT' command to client PROC.
776 QTEXT must be already quoted.
777 This handles splitting the command if it would be bigger than
778 `server-msg-size'."
779 (let ((prefix "-print ")
780 part)
781 (while (> (+ (length qtext) (length prefix) 1) server-msg-size)
782 ;; We have to split the string
783 (setq part (substring qtext 0 (- server-msg-size (length prefix) 1)))
784 ;; Don't split in the middle of a quote sequence
785 (if (string-match "\\(^\\|[^&]\\)\\(&&\\)+$" part)
786 ;; There is an uneven number of & at the end
787 (setq part (substring part 0 -1)))
788 (setq qtext (substring qtext (length part)))
789 (server-send-string proc (concat prefix part "\n"))
790 (setq prefix "-print-nonl "))
791 (server-send-string proc (concat prefix qtext "\n"))))
793 (defun server-create-tty-frame (tty type proc)
794 (unless tty
795 (error "Invalid terminal device"))
796 (unless type
797 (error "Invalid terminal type"))
798 (add-to-list 'frame-inherited-parameters 'client)
799 (let ((frame
800 (server-with-environment
801 (process-get proc 'env)
802 '("LANG" "LC_CTYPE" "LC_ALL"
803 ;; For tgetent(3); list according to ncurses(3).
804 "BAUDRATE" "COLUMNS" "ESCDELAY" "HOME" "LINES"
805 "NCURSES_ASSUMED_COLORS" "NCURSES_NO_PADDING"
806 "NCURSES_NO_SETBUF" "TERM" "TERMCAP" "TERMINFO"
807 "TERMINFO_DIRS" "TERMPATH"
808 ;; rxvt wants these
809 "COLORFGBG" "COLORTERM")
810 (make-frame `((window-system . nil)
811 (tty . ,tty)
812 (tty-type . ,type)
813 ;; Ignore nowait here; we always need to
814 ;; clean up opened ttys when the client dies.
815 (client . ,proc)
816 ;; This is a leftover from an earlier
817 ;; attempt at making it possible for process
818 ;; run in the server process to use the
819 ;; environment of the client process.
820 ;; It has no effect now and to make it work
821 ;; we'd need to decide how to make
822 ;; process-environment interact with client
823 ;; envvars, and then to change the
824 ;; C functions `child_setup' and
825 ;; `getenv_internal' accordingly.
826 (environment . ,(process-get proc 'env)))))))
828 ;; ttys don't use the `display' parameter, but callproc.c does to set
829 ;; the DISPLAY environment on subprocesses.
830 (set-frame-parameter frame 'display
831 (getenv-internal "DISPLAY" (process-get proc 'env)))
832 (select-frame frame)
833 (process-put proc 'frame frame)
834 (process-put proc 'terminal (frame-terminal frame))
835 frame))
837 (defun server-create-window-system-frame (display nowait proc parent-id
838 &optional parameters)
839 (let* ((display (or display
840 (frame-parameter nil 'display)
841 (error "Please specify display.")))
842 (w (or (cdr (assq 'window-system parameters))
843 (window-system-for-display display))))
845 ;; Special case for ns. This is because DISPLAY may not be set at all
846 ;; which in the ns case isn't an error. The variable display then becomes
847 ;; the fully qualified hostname, which make-frame-on-display below
848 ;; does not understand and throws an error.
849 ;; It may also be a valid X display, but if Emacs is compiled for ns, it
850 ;; can not make X frames.
851 (if (featurep 'ns-win)
852 (setq w 'ns display "ns")
853 ;; FIXME! Not sure what this was for, and not sure how it should work
854 ;; in the cl-defmethod new world!
855 ;;(unless (assq w window-system-initialization-alist)
856 ;; (setq w nil))
859 (cond (w
860 ;; Flag frame as client-created, but use a dummy client.
861 ;; This will prevent the frame from being deleted when
862 ;; emacsclient quits while also preventing
863 ;; `server-save-buffers-kill-terminal' from unexpectedly
864 ;; killing emacs on that frame.
865 (let* ((params `((client . ,(if nowait 'nowait proc))
866 ;; This is a leftover, see above.
867 (environment . ,(process-get proc 'env))
868 ,@parameters))
869 frame)
870 (if parent-id
871 (push (cons 'parent-id (string-to-number parent-id)) params))
872 (add-to-list 'frame-inherited-parameters 'client)
873 (setq frame (make-frame-on-display display params))
874 (server-log (format "%s created" frame) proc)
875 (select-frame frame)
876 (process-put proc 'frame frame)
877 (process-put proc 'terminal (frame-terminal frame))
878 frame))
881 (server-log "Window system unsupported" proc)
882 (server-send-string proc "-window-system-unsupported \n")
883 nil))))
885 (defun server-goto-toplevel (proc)
886 (condition-case nil
887 ;; If we're running isearch, we must abort it to allow Emacs to
888 ;; display the buffer and switch to it.
889 (dolist (buffer (buffer-list))
890 (with-current-buffer buffer
891 (when (bound-and-true-p isearch-mode)
892 (isearch-cancel))))
893 ;; Signaled by isearch-cancel.
894 (quit (message nil)))
895 (when (> (recursion-depth) 0)
896 ;; We're inside a minibuffer already, so if the emacs-client is trying
897 ;; to open a frame on a new display, we might end up with an unusable
898 ;; frame because input from that display will be blocked (until exiting
899 ;; the minibuffer). Better exit this minibuffer right away.
900 ;; Similarly with recursive-edits such as the splash screen.
901 (run-with-timer 0 nil (lambda () (server-execute-continuation proc)))
902 (top-level)))
904 ;; We use various special properties on process objects:
905 ;; - `env' stores the info about the environment of the emacsclient process.
906 ;; - `continuation' is a no-arg function that we need to execute. It contains
907 ;; commands we wanted to execute in some earlier invocation of the process
908 ;; filter but that we somehow were unable to process at that time
909 ;; (e.g. because we first need to throw to the toplevel).
911 (defun server-execute-continuation (proc)
912 (let ((continuation (process-get proc 'continuation)))
913 (process-put proc 'continuation nil)
914 (if continuation (ignore-errors (funcall continuation)))))
916 (cl-defun server-process-filter (proc string)
917 "Process a request from the server to edit some files.
918 PROC is the server process. STRING consists of a sequence of
919 commands prefixed by a dash. Some commands have arguments;
920 these are &-quoted and need to be decoded by `server-unquote-arg'.
921 The filter parses and executes these commands.
923 To illustrate the protocol, here is an example command that
924 emacsclient sends to create a new X frame (note that the whole
925 sequence is sent on a single line):
927 -env HOME=/home/lorentey
928 -env DISPLAY=:0.0
929 ... lots of other -env commands
930 -display :0.0
931 -window-system
933 The following commands are accepted by the server:
935 `-auth AUTH-STRING'
936 Authenticate the client using the secret authentication string
937 AUTH-STRING.
939 `-env NAME=VALUE'
940 An environment variable on the client side.
942 `-dir DIRNAME'
943 The current working directory of the client process.
945 `-current-frame'
946 Forbid the creation of new frames.
948 `-frame-parameters ALIST'
949 Set the parameters of the created frame.
951 `-nowait'
952 Request that the next frame created should not be
953 associated with this client.
955 `-display DISPLAY'
956 Set the display name to open X frames on.
958 `-position LINE[:COLUMN]'
959 Go to the given line and column number
960 in the next file opened.
962 `-file FILENAME'
963 Load the given file in the current frame.
965 `-eval EXPR'
966 Evaluate EXPR as a Lisp expression and return the
967 result in -print commands.
969 `-window-system'
970 Open a new X frame.
972 `-tty DEVICENAME TYPE'
973 Open a new tty frame at the client.
975 `-suspend'
976 Suspend this tty frame. The client sends this string in
977 response to SIGTSTP and SIGTTOU. The server must cease all I/O
978 on this tty until it gets a -resume command.
980 `-resume'
981 Resume this tty frame. The client sends this string when it
982 gets the SIGCONT signal and it is the foreground process on its
983 controlling tty.
985 `-ignore COMMENT'
986 Do nothing, but put the comment in the server log.
987 Useful for debugging.
990 The following commands are accepted by the client:
992 `-emacs-pid PID'
993 Describes the process id of the Emacs process;
994 used to forward window change signals to it.
996 `-window-system-unsupported'
997 Signals that the server does not support creating X frames;
998 the client must try again with a tty frame.
1000 `-print STRING'
1001 Print STRING on stdout. Used to send values
1002 returned by -eval.
1004 `-print-nonl STRING'
1005 Print STRING on stdout. Used to continue a
1006 preceding -print command that would be too big to send
1007 in a single message.
1009 `-error DESCRIPTION'
1010 Signal an error and delete process PROC.
1012 `-suspend'
1013 Suspend this terminal, i.e., stop the client process.
1014 Sent when the user presses C-z."
1015 (server-log (concat "Received " string) proc)
1016 ;; First things first: let's check the authentication
1017 (unless (process-get proc :authenticated)
1018 (if (and (string-match "-auth \\([!-~]+\\)\n?" string)
1019 (equal (match-string 1 string) (process-get proc :auth-key)))
1020 (progn
1021 (setq string (substring string (match-end 0)))
1022 (process-put proc :authenticated t)
1023 (server-log "Authentication successful" proc))
1024 (server-log "Authentication failed" proc)
1025 (server-send-string
1026 proc (concat "-error " (server-quote-arg "Authentication failed")))
1027 ;; Before calling `delete-process', give emacsclient time to
1028 ;; receive the error string and shut down on its own.
1029 (sit-for 1)
1030 (delete-process proc)
1031 ;; We return immediately.
1032 (cl-return-from server-process-filter)))
1033 (let ((prev (process-get proc 'previous-string)))
1034 (when prev
1035 (setq string (concat prev string))
1036 (process-put proc 'previous-string nil)))
1037 (condition-case err
1038 (progn
1039 (server-add-client proc)
1040 ;; Send our pid
1041 (server-send-string proc (concat "-emacs-pid "
1042 (number-to-string (emacs-pid)) "\n"))
1043 (if (not (string-match "\n" string))
1044 ;; Save for later any partial line that remains.
1045 (when (> (length string) 0)
1046 (process-put proc 'previous-string string))
1048 ;; In earlier versions of server.el (where we used an `emacsserver'
1049 ;; process), there could be multiple lines. Nowadays this is not
1050 ;; supported any more.
1051 (cl-assert (eq (match-end 0) (length string)))
1052 (let ((request (substring string 0 (match-beginning 0)))
1053 (coding-system (and (default-value 'enable-multibyte-characters)
1054 (or file-name-coding-system
1055 default-file-name-coding-system)))
1056 nowait ; t if emacsclient does not want to wait for us.
1057 frame ; Frame opened for the client (if any).
1058 display ; Open frame on this display.
1059 parent-id ; Window ID for XEmbed
1060 dontkill ; t if client should not be killed.
1061 commands
1063 use-current-frame
1064 frame-parameters ;parameters for newly created frame
1065 tty-name ; nil, `window-system', or the tty name.
1066 tty-type ; string.
1067 files
1068 filepos
1069 args-left)
1070 ;; Remove this line from STRING.
1071 (setq string (substring string (match-end 0)))
1072 (setq args-left
1073 (mapcar 'server-unquote-arg (split-string request " " t)))
1074 (while args-left
1075 (pcase (pop args-left)
1076 ;; -version CLIENT-VERSION: obsolete at birth.
1077 (`"-version" (pop args-left))
1079 ;; -nowait: Emacsclient won't wait for a result.
1080 (`"-nowait" (setq nowait t))
1082 ;; -current-frame: Don't create frames.
1083 (`"-current-frame" (setq use-current-frame t))
1085 ;; -frame-parameters: Set frame parameters
1086 (`"-frame-parameters"
1087 (let ((alist (pop args-left)))
1088 (if coding-system
1089 (setq alist (decode-coding-string alist coding-system)))
1090 (setq frame-parameters (car (read-from-string alist)))))
1092 ;; -display DISPLAY:
1093 ;; Open X frames on the given display instead of the default.
1094 (`"-display"
1095 (setq display (pop args-left))
1096 (if (zerop (length display)) (setq display nil)))
1098 ;; -parent-id ID:
1099 ;; Open X frame within window ID, via XEmbed.
1100 (`"-parent-id"
1101 (setq parent-id (pop args-left))
1102 (if (zerop (length parent-id)) (setq parent-id nil)))
1104 ;; -window-system: Open a new X frame.
1105 (`"-window-system"
1106 (if (fboundp 'x-create-frame)
1107 (setq dontkill t
1108 tty-name 'window-system)))
1110 ;; -resume: Resume a suspended tty frame.
1111 (`"-resume"
1112 (let ((terminal (process-get proc 'terminal)))
1113 (setq dontkill t)
1114 (push (lambda ()
1115 (when (eq (terminal-live-p terminal) t)
1116 (resume-tty terminal)))
1117 commands)))
1119 ;; -suspend: Suspend the client's frame. (In case we
1120 ;; get out of sync, and a C-z sends a SIGTSTP to
1121 ;; emacsclient.)
1122 (`"-suspend"
1123 (let ((terminal (process-get proc 'terminal)))
1124 (setq dontkill t)
1125 (push (lambda ()
1126 (when (eq (terminal-live-p terminal) t)
1127 (suspend-tty terminal)))
1128 commands)))
1130 ;; -ignore COMMENT: Noop; useful for debugging emacsclient.
1131 ;; (The given comment appears in the server log.)
1132 (`"-ignore"
1133 (setq dontkill t)
1134 (pop args-left))
1136 ;; -tty DEVICE-NAME TYPE: Open a new tty frame.
1137 ;; (But if we see -window-system later, use that.)
1138 (`"-tty"
1139 (setq tty-name (pop args-left)
1140 tty-type (pop args-left)
1141 dontkill (or dontkill
1142 (not use-current-frame)))
1143 ;; On Windows, emacsclient always asks for a tty
1144 ;; frame. If running a GUI server, force the frame
1145 ;; type to GUI. (Cygwin is perfectly happy with
1146 ;; multi-tty support, so don't override the user's
1147 ;; choice there.) In daemon mode on Windows, we can't
1148 ;; make tty frames, so force the frame type to GUI
1149 ;; there too.
1150 (when (and (eq system-type 'windows-nt)
1151 (or (daemonp)
1152 (eq window-system 'w32)))
1153 (push "-window-system" args-left)))
1155 ;; -position LINE[:COLUMN]: Set point to the given
1156 ;; position in the next file.
1157 (`"-position"
1158 (if (not (string-match "\\+\\([0-9]+\\)\\(?::\\([0-9]+\\)\\)?"
1159 (car args-left)))
1160 (error "Invalid -position command in client args"))
1161 (let ((arg (pop args-left)))
1162 (setq filepos
1163 (cons (string-to-number (match-string 1 arg))
1164 (string-to-number (or (match-string 2 arg)
1165 ""))))))
1167 ;; -file FILENAME: Load the given file.
1168 (`"-file"
1169 (let ((file (pop args-left)))
1170 (if coding-system
1171 (setq file (decode-coding-string file coding-system)))
1172 ;; Allow Cygwin's emacsclient to be used as a file
1173 ;; handler on MS-Windows, in which case FILENAME
1174 ;; might start with a drive letter.
1175 (when (and (eq system-type 'cygwin)
1176 (string-match "\\`[A-Za-z]:" file))
1177 (setq file (cygwin-convert-file-name-from-windows file)))
1178 (setq file (expand-file-name file dir))
1179 (push (cons file filepos) files)
1180 (server-log (format "New file: %s %s"
1181 file (or filepos ""))
1182 proc))
1183 (setq filepos nil))
1185 ;; -eval EXPR: Evaluate a Lisp expression.
1186 (`"-eval"
1187 (if use-current-frame
1188 (setq use-current-frame 'always))
1189 (let ((expr (pop args-left)))
1190 (if coding-system
1191 (setq expr (decode-coding-string expr coding-system)))
1192 (push (lambda () (server-eval-and-print expr proc))
1193 commands)
1194 (setq filepos nil)))
1196 ;; -env NAME=VALUE: An environment variable.
1197 (`"-env"
1198 (let ((var (pop args-left)))
1199 ;; XXX Variables should be encoded as in getenv/setenv.
1200 (process-put proc 'env
1201 (cons var (process-get proc 'env)))))
1203 ;; -dir DIRNAME: The cwd of the emacsclient process.
1204 (`"-dir"
1205 (setq dir (pop args-left))
1206 (if coding-system
1207 (setq dir (decode-coding-string dir coding-system)))
1208 (setq dir (command-line-normalize-file-name dir))
1209 (process-put proc 'server-client-directory dir))
1211 ;; Unknown command.
1212 (arg (error "Unknown command: %s" arg))))
1214 ;; If both -no-wait and -tty are given with file or sexp
1215 ;; arguments, use an existing frame.
1216 (and nowait
1217 (not (eq tty-name 'window-system))
1218 (or files commands)
1219 (setq use-current-frame t))
1221 (setq frame
1222 (cond
1223 ((and use-current-frame
1224 (or (eq use-current-frame 'always)
1225 ;; We can't use the Emacs daemon's
1226 ;; terminal frame.
1227 (not (and (daemonp)
1228 (null (cdr (frame-list)))
1229 (eq (selected-frame)
1230 terminal-frame)))))
1231 (setq tty-name nil tty-type nil)
1232 (if display (server-select-display display)))
1233 ((or (and (eq system-type 'windows-nt)
1234 (daemonp)
1235 (setq display "w32"))
1236 (eq tty-name 'window-system))
1237 (server-create-window-system-frame display nowait proc
1238 parent-id
1239 frame-parameters))
1240 ;; When resuming on a tty, tty-name is nil.
1241 (tty-name
1242 (server-create-tty-frame tty-name tty-type proc))))
1244 (process-put
1245 proc 'continuation
1246 (lambda ()
1247 (with-current-buffer (get-buffer-create server-buffer)
1248 ;; Use the same cwd as the emacsclient, if possible, so
1249 ;; relative file names work correctly, even in `eval'.
1250 (let ((default-directory
1251 (if (and dir (file-directory-p dir))
1252 dir default-directory)))
1253 (server-execute proc files nowait commands
1254 dontkill frame tty-name)))))
1256 (when (or frame files)
1257 (server-goto-toplevel proc))
1259 (server-execute-continuation proc))))
1260 ;; condition-case
1261 (error (server-return-error proc err))))
1263 (defun server-execute (proc files nowait commands dontkill frame tty-name)
1264 ;; This is run from timers and process-filters, i.e. "asynchronously".
1265 ;; But w.r.t the user, this is not really asynchronous since the timer
1266 ;; is run after 0s and the process-filter is run in response to the
1267 ;; user running `emacsclient'. So it is OK to override the
1268 ;; inhibit-quit flag, which is good since `commands' (as well as
1269 ;; find-file-noselect via the major-mode) can run arbitrary code,
1270 ;; including code that needs to wait.
1271 (with-local-quit
1272 (condition-case err
1273 (let ((buffers (server-visit-files files proc nowait)))
1274 (mapc 'funcall (nreverse commands))
1276 ;; If we were told only to open a new client, obey
1277 ;; `initial-buffer-choice' if it specifies a file
1278 ;; or a function.
1279 (unless (or files commands)
1280 (let ((buf
1281 (cond ((stringp initial-buffer-choice)
1282 (find-file-noselect initial-buffer-choice))
1283 ((functionp initial-buffer-choice)
1284 (funcall initial-buffer-choice)))))
1285 (switch-to-buffer
1286 (if (buffer-live-p buf) buf (get-buffer-create "*scratch*"))
1287 'norecord)))
1289 ;; Delete the client if necessary.
1290 (cond
1291 (nowait
1292 ;; Client requested nowait; return immediately.
1293 (server-log "Close nowait client" proc)
1294 (server-delete-client proc))
1295 ((and (not dontkill) (null buffers))
1296 ;; This client is empty; get rid of it immediately.
1297 (server-log "Close empty client" proc)
1298 (server-delete-client proc)))
1299 (cond
1300 ((or isearch-mode (minibufferp))
1301 nil)
1302 ((and frame (null buffers))
1303 (message "%s" (substitute-command-keys
1304 "When done with this frame, type \\[delete-frame]")))
1305 ((not (null buffers))
1306 (server-switch-buffer (car buffers) nil (cdr (car files)))
1307 (run-hooks 'server-switch-hook)
1308 (unless nowait
1309 (message "%s" (substitute-command-keys
1310 "When done with a buffer, type \\[server-edit]")))))
1311 (when (and frame (null tty-name))
1312 (server-unselect-display frame)))
1313 ((quit error)
1314 (when (eq (car err) 'quit)
1315 (message "Quit emacsclient request"))
1316 (server-return-error proc err)))))
1318 (defun server-return-error (proc err)
1319 (ignore-errors
1320 (server-send-string
1321 proc (concat "-error " (server-quote-arg
1322 (error-message-string err))))
1323 (server-log (error-message-string err) proc)
1324 ;; Before calling `delete-process', give emacsclient time to
1325 ;; receive the error string and shut down on its own.
1326 (sit-for 5)
1327 (delete-process proc)))
1329 (defun server-goto-line-column (line-col)
1330 "Move point to the position indicated in LINE-COL.
1331 LINE-COL should be a pair (LINE . COL)."
1332 (when line-col
1333 (goto-char (point-min))
1334 (forward-line (1- (car line-col)))
1335 (let ((column-number (cdr line-col)))
1336 (when (> column-number 0)
1337 (move-to-column (1- column-number))))))
1339 (defun server-visit-files (files proc &optional nowait)
1340 "Find FILES and return a list of buffers created.
1341 FILES is an alist whose elements are (FILENAME . FILEPOS)
1342 where FILEPOS can be nil or a pair (LINENUMBER . COLUMNNUMBER).
1343 PROC is the client that requested this operation.
1344 NOWAIT non-nil means this client is not waiting for the results,
1345 so don't mark these buffers specially, just visit them normally."
1346 ;; Bind last-nonmenu-event to force use of keyboard, not mouse, for queries.
1347 (let ((last-nonmenu-event t) client-record)
1348 ;; Restore the current buffer afterward, but not using save-excursion,
1349 ;; because we don't want to save point in this buffer
1350 ;; if it happens to be one of those specified by the server.
1351 (save-current-buffer
1352 (dolist (file files)
1353 ;; If there is an existing buffer modified or the file is
1354 ;; modified, revert it. If there is an existing buffer with
1355 ;; deleted file, offer to write it.
1356 (let* ((minibuffer-auto-raise (or server-raise-frame
1357 minibuffer-auto-raise))
1358 (filen (car file))
1359 (obuf (get-file-buffer filen)))
1360 (add-to-history 'file-name-history filen)
1361 (if (null obuf)
1362 (progn
1363 (run-hooks 'pre-command-hook)
1364 (set-buffer (find-file-noselect filen)))
1365 (set-buffer obuf)
1366 ;; separately for each file, in sync with post-command hooks,
1367 ;; with the new buffer current:
1368 (run-hooks 'pre-command-hook)
1369 (cond ((file-exists-p filen)
1370 (when (not (verify-visited-file-modtime obuf))
1371 (revert-buffer t nil)))
1373 (when (y-or-n-p
1374 (concat "File no longer exists: " filen
1375 ", write buffer to file? "))
1376 (write-file filen))))
1377 (unless server-buffer-clients
1378 (setq server-existing-buffer t)))
1379 (server-goto-line-column (cdr file))
1380 (run-hooks 'server-visit-hook)
1381 ;; hooks may be specific to current buffer:
1382 (run-hooks 'post-command-hook))
1383 (unless nowait
1384 ;; When the buffer is killed, inform the clients.
1385 (add-hook 'kill-buffer-hook 'server-kill-buffer nil t)
1386 (push proc server-buffer-clients))
1387 (push (current-buffer) client-record)))
1388 (unless nowait
1389 (process-put proc 'buffers
1390 (nconc (process-get proc 'buffers) client-record)))
1391 client-record))
1393 (defvar server-kill-buffer-running nil
1394 "Non-nil while `server-kill-buffer' or `server-buffer-done' is running.")
1396 (defun server-buffer-done (buffer &optional for-killing)
1397 "Mark BUFFER as \"done\" for its client(s).
1398 This buries the buffer, then returns a list of the form (NEXT-BUFFER KILLED).
1399 NEXT-BUFFER is another server buffer, as a suggestion for what to select next,
1400 or nil. KILLED is t if we killed BUFFER (typically, because it was visiting
1401 a temp file).
1402 FOR-KILLING if non-nil indicates that we are called from `kill-buffer'."
1403 (let ((next-buffer nil)
1404 (killed nil))
1405 (dolist (proc server-clients)
1406 (let ((buffers (process-get proc 'buffers)))
1407 (or next-buffer
1408 (setq next-buffer (nth 1 (memq buffer buffers))))
1409 (when buffers ; Ignore bufferless clients.
1410 (setq buffers (delq buffer buffers))
1411 ;; Delete all dead buffers from PROC.
1412 (dolist (b buffers)
1413 (and (bufferp b)
1414 (not (buffer-live-p b))
1415 (setq buffers (delq b buffers))))
1416 (process-put proc 'buffers buffers)
1417 ;; If client now has no pending buffers,
1418 ;; tell it that it is done, and forget it entirely.
1419 (unless buffers
1420 (server-log "Close" proc)
1421 (if for-killing
1422 ;; `server-delete-client' might delete the client's
1423 ;; frames, which might change the current buffer. We
1424 ;; don't want that (bug#640).
1425 (save-current-buffer
1426 (server-delete-client proc))
1427 (server-delete-client proc))))))
1428 (when (and (bufferp buffer) (buffer-name buffer))
1429 ;; We may or may not kill this buffer;
1430 ;; if we do, do not call server-buffer-done recursively
1431 ;; from kill-buffer-hook.
1432 (let ((server-kill-buffer-running t))
1433 (with-current-buffer buffer
1434 (setq server-buffer-clients nil)
1435 (run-hooks 'server-done-hook))
1436 ;; Notice whether server-done-hook killed the buffer.
1437 (if (null (buffer-name buffer))
1438 (setq killed t)
1439 ;; Don't bother killing or burying the buffer
1440 ;; when we are called from kill-buffer.
1441 (unless for-killing
1442 (when (and (not killed)
1443 server-kill-new-buffers
1444 (with-current-buffer buffer
1445 (not server-existing-buffer)))
1446 (setq killed t)
1447 (bury-buffer buffer)
1448 ;; Prevent kill-buffer from prompting (Bug#3696).
1449 (with-current-buffer buffer
1450 (set-buffer-modified-p nil))
1451 (kill-buffer buffer))
1452 (unless killed
1453 (if (server-temp-file-p buffer)
1454 (progn
1455 (with-current-buffer buffer
1456 (set-buffer-modified-p nil))
1457 (kill-buffer buffer)
1458 (setq killed t))
1459 (bury-buffer buffer)))))))
1460 (list next-buffer killed)))
1462 (defun server-temp-file-p (&optional buffer)
1463 "Return non-nil if BUFFER contains a file considered temporary.
1464 These are files whose names suggest they are repeatedly
1465 reused to pass information to another program.
1467 The variable `server-temp-file-regexp' controls which filenames
1468 are considered temporary."
1469 (and (buffer-file-name buffer)
1470 (string-match-p server-temp-file-regexp (buffer-file-name buffer))))
1472 (defun server-done ()
1473 "Offer to save current buffer, mark it as \"done\" for clients.
1474 This kills or buries the buffer, then returns a list
1475 of the form (NEXT-BUFFER KILLED). NEXT-BUFFER is another server buffer,
1476 as a suggestion for what to select next, or nil.
1477 KILLED is t if we killed BUFFER, which happens if it was created
1478 specifically for the clients and did not exist before their request for it."
1479 (when server-buffer-clients
1480 (if (server-temp-file-p)
1481 ;; For a temp file, save, and do make a non-numeric backup
1482 ;; (unless make-backup-files is nil).
1483 (let ((version-control nil)
1484 (buffer-backed-up nil))
1485 (save-buffer))
1486 (when (and (buffer-modified-p)
1487 buffer-file-name
1488 (y-or-n-p (concat "Save file " buffer-file-name "? ")))
1489 (save-buffer)))
1490 (server-buffer-done (current-buffer))))
1492 (defun server-kill-emacs-query-function ()
1493 "Ask before exiting Emacs if it has live clients."
1494 (or (not server-clients)
1495 (let (live-client)
1496 (dolist (proc server-clients)
1497 (when (memq t (mapcar 'buffer-live-p (process-get
1498 proc 'buffers)))
1499 (setq live-client t)))
1500 live-client)
1501 (yes-or-no-p "This Emacs session has clients; exit anyway? ")))
1503 (defun server-kill-buffer ()
1504 "Remove the current buffer from its clients' buffer list.
1505 Designed to be added to `kill-buffer-hook'."
1506 ;; Prevent infinite recursion if user has made server-done-hook
1507 ;; call kill-buffer.
1508 (or server-kill-buffer-running
1509 (and server-buffer-clients
1510 (let ((server-kill-buffer-running t))
1511 (when server-process
1512 (server-buffer-done (current-buffer) t))))))
1514 (defun server-edit (&optional arg)
1515 "Switch to next server editing buffer; say \"Done\" for current buffer.
1516 If a server buffer is current, it is marked \"done\" and optionally saved.
1517 The buffer is also killed if it did not exist before the clients asked for it.
1518 When all of a client's buffers are marked as \"done\", the client is notified.
1520 Temporary files such as MH <draft> files are always saved and backed up,
1521 no questions asked. (The variable `make-backup-files', if nil, still
1522 inhibits a backup; you can set it locally in a particular buffer to
1523 prevent a backup for it.) The variable `server-temp-file-regexp' controls
1524 which filenames are considered temporary.
1526 If invoked with a prefix argument, or if there is no server process running,
1527 starts server process and that is all. Invoked by \\[server-edit]."
1528 (interactive "P")
1529 (cond
1530 ((or arg
1531 (not server-process)
1532 (memq (process-status server-process) '(signal exit)))
1533 (server-mode 1))
1534 (server-clients (apply 'server-switch-buffer (server-done)))
1535 (t (message "No server editing buffers exist"))))
1537 (defun server-switch-buffer (&optional next-buffer killed-one filepos)
1538 "Switch to another buffer, preferably one that has a client.
1539 Arg NEXT-BUFFER is a suggestion; if it is a live buffer, use it.
1541 KILLED-ONE is t in a recursive call if we have already killed one
1542 temp-file server buffer. This means we should avoid the final
1543 \"switch to some other buffer\" since we've already effectively
1544 done that.
1546 FILEPOS specifies a new buffer position for NEXT-BUFFER, if we
1547 visit NEXT-BUFFER in an existing window. If non-nil, it should
1548 be a cons cell (LINENUMBER . COLUMNNUMBER)."
1549 (if (null next-buffer)
1550 (progn
1551 (let ((rest server-clients))
1552 (while (and rest (not next-buffer))
1553 (let ((proc (car rest)))
1554 ;; Only look at frameless clients, or those in the selected
1555 ;; frame.
1556 (when (or (not (process-get proc 'frame))
1557 (eq (process-get proc 'frame) (selected-frame)))
1558 (setq next-buffer (car (process-get proc 'buffers))))
1559 (setq rest (cdr rest)))))
1560 (and next-buffer (server-switch-buffer next-buffer killed-one))
1561 (unless (or next-buffer killed-one (window-dedicated-p))
1562 ;; (switch-to-buffer (other-buffer))
1563 (message "No server buffers remain to edit")))
1564 (if (not (buffer-live-p next-buffer))
1565 ;; If NEXT-BUFFER is a dead buffer, remove the server records for it
1566 ;; and try the next surviving server buffer.
1567 (apply 'server-switch-buffer (server-buffer-done next-buffer))
1568 ;; OK, we know next-buffer is live, let's display and select it.
1569 (if (functionp server-window)
1570 (funcall server-window next-buffer)
1571 (let ((win (get-buffer-window next-buffer 0)))
1572 (if (and win (not server-window))
1573 ;; The buffer is already displayed: just reuse the
1574 ;; window. If FILEPOS is non-nil, use it to replace the
1575 ;; window's own value of point.
1576 (progn
1577 (select-window win)
1578 (set-buffer next-buffer)
1579 (when filepos
1580 (server-goto-line-column filepos)))
1581 ;; Otherwise, let's find an appropriate window.
1582 (cond ((window-live-p server-window)
1583 (select-window server-window))
1584 ((framep server-window)
1585 (unless (frame-live-p server-window)
1586 (setq server-window (make-frame)))
1587 (select-window (frame-selected-window server-window))))
1588 (when (window-minibuffer-p)
1589 (select-window (next-window nil 'nomini 0)))
1590 ;; Move to a non-dedicated window, if we have one.
1591 (when (window-dedicated-p)
1592 (select-window
1593 (get-window-with-predicate
1594 (lambda (w)
1595 (and (not (window-dedicated-p w))
1596 (equal (frame-terminal (window-frame w))
1597 (frame-terminal))))
1598 'nomini 'visible (selected-window))))
1599 (condition-case nil
1600 (switch-to-buffer next-buffer)
1601 ;; After all the above, we might still have ended up with
1602 ;; a minibuffer/dedicated-window (if there's no other).
1603 (error (pop-to-buffer next-buffer)))))))
1604 (when server-raise-frame
1605 (select-frame-set-input-focus (window-frame)))))
1607 ;;;###autoload
1608 (defun server-save-buffers-kill-terminal (arg)
1609 ;; Called from save-buffers-kill-terminal in files.el.
1610 "Offer to save each buffer, then kill the current client.
1611 With ARG non-nil, silently save all file-visiting buffers, then kill.
1613 If emacsclient was started with a list of filenames to edit, then
1614 only these files will be asked to be saved."
1615 (let ((proc (frame-parameter nil 'client)))
1616 (cond ((eq proc 'nowait)
1617 ;; Nowait frames have no client buffer list.
1618 (if (cdr (frame-list))
1619 (progn (save-some-buffers arg)
1620 (delete-frame))
1621 ;; If we're the last frame standing, kill Emacs.
1622 (save-buffers-kill-emacs arg)))
1623 ((processp proc)
1624 (let ((buffers (process-get proc 'buffers)))
1625 ;; If client is bufferless, emulate a normal Emacs exit
1626 ;; and offer to save all buffers. Otherwise, offer to
1627 ;; save only the buffers belonging to the client.
1628 (save-some-buffers
1629 arg (if buffers
1630 (lambda () (memq (current-buffer) buffers))
1632 (server-delete-client proc)))
1633 (t (error "Invalid client frame")))))
1635 (define-key ctl-x-map "#" 'server-edit)
1637 (defun server-unload-function ()
1638 "Unload the Server library."
1639 (server-mode -1)
1640 (substitute-key-definition 'server-edit nil ctl-x-map)
1641 (save-current-buffer
1642 (dolist (buffer (buffer-list))
1643 (set-buffer buffer)
1644 (remove-hook 'kill-buffer-hook 'server-kill-buffer t)))
1645 ;; continue standard unloading
1646 nil)
1648 (defun server-eval-at (server form)
1649 "Contact the Emacs server named SERVER and evaluate FORM there.
1650 Returns the result of the evaluation, or signals an error if it
1651 cannot contact the specified server. For example:
1652 (server-eval-at \"server\" \\='(emacs-pid))
1653 returns the process ID of the Emacs instance running \"server\"."
1654 (let* ((server-dir (if server-use-tcp server-auth-dir server-socket-dir))
1655 (server-file (expand-file-name server server-dir))
1656 (coding-system-for-read 'binary)
1657 (coding-system-for-write 'binary)
1658 address port secret process)
1659 (unless (file-exists-p server-file)
1660 (error "No such server: %s" server))
1661 (with-temp-buffer
1662 (when server-use-tcp
1663 (let ((coding-system-for-read 'no-conversion))
1664 (insert-file-contents server-file)
1665 (unless (looking-at "\\([0-9.]+\\):\\([0-9]+\\)")
1666 (error "Invalid auth file"))
1667 (setq address (match-string 1)
1668 port (string-to-number (match-string 2)))
1669 (forward-line 1)
1670 (setq secret (buffer-substring (point) (line-end-position)))
1671 (erase-buffer)))
1672 (unless (setq process (make-network-process
1673 :name "eval-at"
1674 :buffer (current-buffer)
1675 :host address
1676 :service (if server-use-tcp port server-file)
1677 :family (if server-use-tcp 'ipv4 'local)
1678 :noquery t))
1679 (error "Unable to contact the server"))
1680 (if server-use-tcp
1681 (process-send-string process (concat "-auth " secret "\n")))
1682 (process-send-string process
1683 (concat "-eval "
1684 (server-quote-arg (format "%S" form))
1685 "\n"))
1686 (while (memq (process-status process) '(open run))
1687 (accept-process-output process 0 10))
1688 (goto-char (point-min))
1689 ;; If the result is nil, there's nothing in the buffer. If the
1690 ;; result is non-nil, it's after "-print ".
1691 (let ((answer ""))
1692 (while (re-search-forward "\n-print\\(-nonl\\)? " nil t)
1693 (setq answer
1694 (concat answer
1695 (buffer-substring (point)
1696 (progn (skip-chars-forward "^\n")
1697 (point))))))
1698 (if (not (equal answer ""))
1699 (read (decode-coding-string (server-unquote-arg answer)
1700 'emacs-internal)))))))
1703 (provide 'server)
1705 ;;; server.el ends here