1 ;;; server.el --- Lisp code for GNU Emacs running as server process
3 ;; Copyright (C) 1986, 1987, 1992, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
4 ;; 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008 Free Software Foundation, Inc.
6 ;; Author: William Sommerfeld <wesommer@athena.mit.edu>
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/>.
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
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.
78 ;; - handle command-line-args-left.
79 ;; - move most of the args processing and decision making from emacsclient.c
81 ;; - fix up handling of the client's environment (place it in the terminal?).
85 (eval-when-compile (require 'cl
))
88 "Emacs running as a server process."
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
))
96 (unless load-in-progress
97 (message "Local sockets unsupported, using TCP sockets")))
99 (set-default sym val
))
104 (defcustom server-host nil
105 "The name or IP address to use as host address of the server process.
106 If set, the server accepts remote connections; otherwise it is local."
109 (string :tag
"Name or IP address")
110 (const :tag
"Local" nil
))
112 (put 'server-host
'risky-local-variable t
)
114 (defcustom server-auth-dir
(locate-user-emacs-file "server/")
115 "Directory for server authentication files."
119 (put 'server-auth-dir
'risky-local-variable t
)
121 (defcustom server-raise-frame t
122 "If non-nil, raise frame when switching to a buffer."
127 (defcustom server-visit-hook nil
128 "Hook run when visiting a file for the Emacs server."
132 (defcustom server-switch-hook nil
133 "Hook run when switching to a buffer for the Emacs server."
137 (defcustom server-done-hook nil
138 "Hook run when done editing a buffer for the Emacs server."
142 (defvar server-process nil
143 "The current server process.")
145 (defvar server-clients nil
146 "List of current server clients.
147 Each element is a process.")
149 (defvar server-buffer-clients nil
150 "List of client processes requesting editing of current buffer.")
151 (make-variable-buffer-local 'server-buffer-clients
)
152 ;; Changing major modes should not erase this local.
153 (put 'server-buffer-clients
'permanent-local t
)
155 (defcustom server-window nil
156 "Specification of the window to use for selecting Emacs server buffers.
157 If nil, use the selected window.
158 If it is a function, it should take one argument (a buffer) and
159 display and select it. A common value is `pop-to-buffer'.
160 If it is a window, use that.
161 If it is a frame, use the frame's selected window.
163 It is not meaningful to set this to a specific frame or window with Custom.
164 Only programs can do so."
167 :type
'(choice (const :tag
"Use selected window"
168 :match
(lambda (widget value
)
169 (not (functionp value
)))
171 (function-item :tag
"Display in new frame" switch-to-buffer-other-frame
)
172 (function-item :tag
"Use pop-to-buffer" pop-to-buffer
)
173 (function :tag
"Other function")))
175 (defcustom server-temp-file-regexp
"^/tmp/Re\\|/draft$"
176 "Regexp matching names of temporary files.
177 These are deleted and reused after each edit by the programs that
178 invoke the Emacs server."
182 (defcustom server-kill-new-buffers t
183 "Whether to kill buffers when done with them.
184 If non-nil, kill a buffer unless it already existed before editing
185 it with the Emacs server. If nil, kill only buffers as specified by
186 `server-temp-file-regexp'.
187 Please note that only buffers that still have a client are killed,
188 i.e. buffers visited with \"emacsclient --no-wait\" are never killed in
194 (or (assq 'server-buffer-clients minor-mode-alist
)
195 (push '(server-buffer-clients " Server") minor-mode-alist
))
197 (defvar server-existing-buffer nil
198 "Non-nil means the buffer existed before the server was asked to visit it.
199 This means that the server should not kill the buffer when you say you
200 are done with it in the server.")
201 (make-variable-buffer-local 'server-existing-buffer
)
203 (defvar server-name
"server")
205 (defvar server-socket-dir
206 (format "%s/emacs%d" (or (getenv "TMPDIR") "/tmp") (user-uid))
207 "The directory in which to place the server socket.")
209 (defun server-clients-with (property value
)
210 "Return a list of clients with PROPERTY set to VALUE."
212 (dolist (proc server-clients result
)
213 (when (equal value
(process-get proc property
))
214 (push proc result
)))))
216 (defun server-add-client (proc)
217 "Create a client for process PROC, if it doesn't already have one.
218 New clients have no properties."
219 (add-to-list 'server-clients proc
))
221 (defmacro server-with-environment
(env vars
&rest body
)
222 "Evaluate BODY with environment variables VARS set to those in ENV.
223 The environment variables are then restored to their previous values.
225 VARS should be a list of strings.
226 ENV should be in the same format as `process-environment'."
228 (let ((var (make-symbol "var"))
229 (value (make-symbol "value")))
230 `(let ((process-environment process-environment
))
232 (let ((,value
(getenv-internal ,var
,env
)))
233 (push (if (null ,value
)
235 (concat ,var
"=" ,value
))
236 process-environment
)))
239 (defun server-delete-client (proc &optional noframe
)
240 "Delete PROC, including its buffers, terminals and frames.
241 If NOFRAME is non-nil, let the frames live. (To be used from
242 `delete-frame-functions'.)"
243 (server-log (concat "server-delete-client" (if noframe
" noframe")) proc
)
244 ;; Force a new lookup of client (prevents infinite recursion).
245 (when (memq proc server-clients
)
246 (let ((buffers (process-get proc
'buffers
)))
248 ;; Kill the client's buffers.
249 (dolist (buf buffers
)
250 (when (buffer-live-p buf
)
251 (with-current-buffer buf
252 ;; Kill the buffer if necessary.
253 (when (and (equal server-buffer-clients
255 (or (and server-kill-new-buffers
256 (not server-existing-buffer
))
257 (server-temp-file-p))
258 (not (buffer-modified-p)))
261 (progn (setq server-buffer-clients nil
)
262 (kill-buffer (current-buffer))
265 ;; Restore clients if user pressed C-g in `kill-buffer'.
266 (setq server-buffer-clients
(list proc
)))))))))
268 ;; Delete the client's frames.
270 (dolist (frame (frame-list))
271 (when (and (frame-live-p frame
)
272 (equal proc
(frame-parameter frame
'client
)))
273 ;; Prevent `server-handle-delete-frame' from calling us
275 (set-frame-parameter frame
'client nil
)
276 (delete-frame frame
))))
278 (setq server-clients
(delq proc server-clients
))
280 ;; Delete the client's tty.
281 (let ((terminal (process-get proc
'terminal
)))
282 ;; Only delete the terminal if it is non-nil.
283 (when (and terminal
(eq (terminal-live-p terminal
) t
))
284 (delete-terminal terminal
)))
286 ;; Delete the client's process.
287 (if (eq (process-status proc
) 'open
)
288 (delete-process proc
))
290 (server-log "Deleted" proc
))))
292 (defvar server-log-time-function
'current-time-string
293 "Function to generate timestamps for `server-buffer'.")
295 (defconst server-buffer
" *server*"
296 "Buffer used internally by Emacs's server.
297 One use is to log the I/O for debugging purposes (see `server-log'),
298 the other is to provide a current buffer in which the process filter can
299 safely let-bind buffer-local variables like `default-directory'.")
301 (defvar server-log nil
302 "If non-nil, log the server's inputs and outputs in the `server-buffer'.")
304 (defun server-log (string &optional client
)
305 "If `server-log' is non-nil, log STRING to `server-buffer'.
306 If CLIENT is non-nil, add a description of it to the logged message."
308 (with-current-buffer (get-buffer-create server-buffer
)
309 (goto-char (point-max))
310 (insert (funcall server-log-time-function
)
313 ((listp client
) (format " %s: " (car client
)))
314 (t (format " %s: " client
)))
316 (or (bolp) (newline)))))
318 (defun server-sentinel (proc msg
)
319 "The process sentinel for Emacs server connections."
320 ;; If this is a new client process, set the query-on-exit flag to nil
321 ;; for this process (it isn't inherited from the server process).
322 (when (and (eq (process-status proc
) 'open
)
323 (process-query-on-exit-flag proc
))
324 (set-process-query-on-exit-flag proc nil
))
325 ;; Delete the associated connection file, if applicable.
326 ;; This is actually problematic: the file may have been overwritten by
327 ;; another Emacs server in the mean time, so it's not ours any more.
328 ;; (and (process-contact proc :server)
329 ;; (eq (process-status proc) 'closed)
330 ;; (ignore-errors (delete-file (process-get proc :server-file))))
331 (server-log (format "Status changed to %s: %s" (process-status proc
) msg
) proc
)
332 (server-delete-client proc
))
334 (defun server-select-display (display)
335 ;; If the current frame is on `display' we're all set.
336 ;; Similarly if we are unable to open a frames on other displays, there's
337 ;; nothing more we can do.
338 (unless (or (not (fboundp 'make-frame-on-display
))
339 (equal (frame-parameter (selected-frame) 'display
) display
))
340 ;; Otherwise, look for an existing frame there and select it.
341 (dolist (frame (frame-list))
342 (when (equal (frame-parameter frame
'display
) display
)
343 (select-frame frame
)))
344 ;; If there's no frame on that display yet, create and select one.
345 (unless (equal (frame-parameter (selected-frame) 'display
) display
)
346 (let* ((buffer (generate-new-buffer " *server-dummy*"))
347 (frame (make-frame-on-display
349 ;; Make it display (and remember) some dummy buffer, so
350 ;; we can detect later if the frame is in use or not.
351 `((server-dummy-buffer .
,buffer
)
352 ;; This frame may be deleted later (see
353 ;; server-unselect-display) so we want it to be as
354 ;; unobtrusive as possible.
355 (visibility . nil
)))))
357 (set-window-buffer (selected-window) buffer
)
360 (defun server-unselect-display (frame)
361 (when (frame-live-p frame
)
362 ;; If the temporary frame is in use (displays something real), make it
363 ;; visible. If not (which can happen if the user's customizations call
364 ;; pop-to-buffer etc.), delete it to avoid preserving the connection after
365 ;; the last real frame is deleted.
366 (if (and (eq (frame-first-window frame
)
367 (next-window (frame-first-window frame
) 'nomini
))
368 (eq (window-buffer (frame-first-window frame
))
369 (frame-parameter frame
'server-dummy-buffer
)))
370 ;; The temp frame still only shows one buffer, and that is the
371 ;; internal temp buffer.
373 (set-frame-parameter frame
'visibility t
))
374 (kill-buffer (frame-parameter frame
'server-dummy-buffer
))
375 (set-frame-parameter frame
'server-dummy-buffer nil
)))
377 (defun server-handle-delete-frame (frame)
378 "Delete the client connection when the emacsclient frame is deleted."
379 (let ((proc (frame-parameter frame
'client
)))
380 (when (and (frame-live-p frame
)
382 ;; See if this is the last frame for this client.
383 (>= 1 (let ((frame-num 0))
384 (dolist (f (frame-list))
385 (when (eq proc
(frame-parameter f
'client
))
386 (setq frame-num
(1+ frame-num
))))
388 (server-log (format "server-handle-delete-frame, frame %s" frame
) proc
)
389 (server-delete-client proc
'noframe
)))) ; Let delete-frame delete the frame later.
391 (defun server-handle-suspend-tty (terminal)
392 "Notify the emacsclient process to suspend itself when its tty device is suspended."
393 (dolist (proc (server-clients-with 'terminal terminal
))
394 (server-log (format "server-handle-suspend-tty, terminal %s" terminal
) proc
)
396 (server-send-string proc
"-suspend \n")
397 (file-error ;The pipe/socket was closed.
398 (ignore-errors (server-delete-client proc
))))))
400 (defun server-unquote-arg (arg)
401 "Remove &-quotation from ARG.
402 See `server-quote-arg' and `server-process-filter'."
403 (replace-regexp-in-string
412 (defun server-quote-arg (arg)
413 "In ARG, insert a & before each &, each space, each newline, and -.
414 Change spaces to underscores, too, so that the return value never
417 See `server-unquote-arg' and `server-process-filter'."
418 (replace-regexp-in-string
419 "[-&\n ]" (lambda (s)
427 (defun server-send-string (proc string
)
428 "A wrapper around `proc-send-string' for logging."
429 (server-log (concat "Sent " string
) proc
)
430 (process-send-string proc string
))
432 (defun server-ensure-safe-dir (dir)
433 "Make sure DIR is a directory with no race-condition issues.
434 Creates the directory if necessary and makes sure:
435 - there's no symlink involved
437 - it's not readable/writable by anybody else."
438 (setq dir
(directory-file-name dir
))
439 (let ((attrs (file-attributes dir
)))
441 (letf (((default-file-modes) ?
\700)) (make-directory dir t
))
442 (setq attrs
(file-attributes dir
)))
443 ;; Check that it's safe for use.
444 (unless (and (eq t
(car attrs
)) (eql (nth 2 attrs
) (user-uid))
445 (or (eq system-type
'windows-nt
)
446 (zerop (logand ?
\077 (file-modes dir
)))))
447 (error "The directory %s is unsafe" dir
))))
450 (defun server-start (&optional leave-dead
)
451 "Allow this Emacs process to be a server for client processes.
452 This starts a server communications subprocess through which
453 client \"editors\" can send your editing commands to this Emacs
454 job. To use the server, set up the program `emacsclient' in the
455 Emacs distribution as your standard \"editor\".
457 Optional argument LEAVE-DEAD (interactively, a prefix arg) means just
458 kill any existing server communications subprocess."
463 "The current server still has clients; delete them? "))
466 (ignore-errors (delete-process server-process
)))
467 ;; Delete the socket files made by previous server invocations.
469 (delete-file (expand-file-name server-name server-socket-dir
))
471 ;; If this Emacs already had a server, clear out associated status.
472 (while server-clients
473 (server-delete-client (car server-clients
)))
474 ;; Now any previous server is properly stopped.
477 (server-log (message "Server stopped"))
478 (setq server-process nil
))
479 (let* ((server-dir (if server-use-tcp server-auth-dir server-socket-dir
))
480 (server-file (expand-file-name server-name server-dir
)))
481 ;; Make sure there is a safe directory in which to place the socket.
482 (server-ensure-safe-dir server-dir
)
483 ;; Remove any leftover socket or authentication file.
484 (ignore-errors (delete-file server-file
))
486 (server-log (message "Restarting server")))
487 (letf (((default-file-modes) ?
\700))
488 (add-hook 'suspend-tty-functions
'server-handle-suspend-tty
)
489 (add-hook 'delete-frame-functions
'server-handle-delete-frame
)
490 (add-hook 'kill-buffer-query-functions
'server-kill-buffer-query-function
)
491 (add-hook 'kill-emacs-query-functions
'server-kill-emacs-query-function
)
492 (add-hook 'kill-emacs-hook
(lambda () (server-mode -
1))) ;Cleanup upon exit.
494 (apply #'make-network-process
498 :sentinel
'server-sentinel
499 :filter
'server-process-filter
500 ;; We must receive file names without being decoded.
501 ;; Those are decoded by server-process-filter according
502 ;; to file-name-coding-system. Also don't get
503 ;; confused by CRs since we don't quote them.
504 :coding
'raw-text-unix
505 ;; The other args depend on the kind of socket used.
509 :host
(or server-host
'local
)
510 :plist
'(:authenticated nil
))
513 :plist
'(:authenticated t
)))))
514 (unless server-process
(error "Could not start server process"))
518 ;; The auth key is a 64-byte string of random chars in the
521 collect
(+ 33 (random 94)) into auth
522 finally return
(concat auth
))))
523 (process-put server-process
:auth-key auth-key
)
524 (with-temp-file server-file
525 (set-buffer-multibyte nil
)
526 (setq buffer-file-coding-system
'no-conversion
)
527 (insert (format-network-address
528 (process-contact server-process
:local
))
529 " " (int-to-string (emacs-pid))
530 "\n" auth-key
)))))))))
532 (defun server-running-p (&optional name
)
533 "Test whether server NAME is running."
535 (list (if current-prefix-arg
536 (read-string "Server name: " nil nil server-name
))))
537 (unless name
(setq name server-name
))
541 (make-network-process
542 :name
"server-client-test" :family
'local
:server nil
:noquery t
543 :service
(expand-file-name name server-socket-dir
)))
548 (define-minor-mode server-mode
550 With ARG, turn Server mode on if ARG is positive, off otherwise.
551 Server mode runs a process that accepts commands from the
552 `emacsclient' program. See `server-start' and Info node `Emacs server'."
556 ;; Fixme: Should this check for an existing server socket and do
557 ;; nothing if there is one (for multiple Emacs sessions)?
558 (server-start (not server-mode
)))
560 (defun server-eval-and-print (expr proc
)
561 "Eval EXPR and send the result back to client PROC."
562 (let ((v (eval (car (read-from-string expr
)))))
565 (let ((standard-output (current-buffer)))
567 (let ((text (buffer-substring-no-properties
568 (point-min) (point-max))))
570 proc
(format "-print %s\n"
571 (server-quote-arg text
)))))))))
573 (defun server-create-tty-frame (tty type proc
)
574 (add-to-list 'frame-inherited-parameters
'client
)
576 (server-with-environment (process-get proc
'env
)
577 '("LANG" "LC_CTYPE" "LC_ALL"
578 ;; For tgetent(3); list according to ncurses(3).
579 "BAUDRATE" "COLUMNS" "ESCDELAY" "HOME" "LINES"
580 "NCURSES_ASSUMED_COLORS" "NCURSES_NO_PADDING"
581 "NCURSES_NO_SETBUF" "TERM" "TERMCAP" "TERMINFO"
582 "TERMINFO_DIRS" "TERMPATH"
584 "COLORFGBG" "COLORTERM")
585 (make-frame-on-tty tty type
586 ;; Ignore nowait here; we always need to
587 ;; clean up opened ttys when the client dies.
589 ;; This is a leftover from an earlier
590 ;; attempt at making it possible for process
591 ;; run in the server process to use the
592 ;; environment of the client process.
593 ;; It has no effect now and to make it work
594 ;; we'd need to decide how to make
595 ;; process-environment interact with client
596 ;; envvars, and then to change the
597 ;; C functions `child_setup' and
598 ;; `getenv_internal' accordingly.
599 (environment .
,(process-get proc
'env
)))))))
601 ;; ttys don't use the `display' parameter, but callproc.c does to set
602 ;; the DISPLAY environment on subprocesses.
603 (set-frame-parameter frame
'display
604 (getenv-internal "DISPLAY" (process-get proc
'env
)))
606 (process-put proc
'frame frame
)
607 (process-put proc
'terminal
(frame-terminal frame
))
609 ;; Display *scratch* by default.
610 (switch-to-buffer (get-buffer-create "*scratch*") 'norecord
)
612 ;; Reply with our pid.
613 (server-send-string proc
(concat "-emacs-pid "
614 (number-to-string (emacs-pid)) "\n"))
617 (defun server-create-window-system-frame (display nowait proc
)
618 (add-to-list 'frame-inherited-parameters
'client
)
619 (if (not (fboundp 'make-frame-on-display
))
621 ;; This emacs does not support X.
622 (server-log "Window system unsupported" proc
)
623 (server-send-string proc
"-window-system-unsupported \n")
625 ;; Flag frame as client-created, but use a dummy client.
626 ;; This will prevent the frame from being deleted when
627 ;; emacsclient quits while also preventing
628 ;; `server-save-buffers-kill-terminal' from unexpectedly
629 ;; killing emacs on that frame.
630 (let* ((params `((client .
,(if nowait
'nowait proc
))
631 ;; This is a leftover, see above.
632 (environment .
,(process-get proc
'env
))))
633 (frame (make-frame-on-display
635 (frame-parameter nil
'display
)
637 (error "Please specify display"))
639 (server-log (format "%s created" frame
) proc
)
641 (process-put proc
'frame frame
)
642 (process-put proc
'terminal
(frame-terminal frame
))
644 ;; Display *scratch* by default.
645 (switch-to-buffer (get-buffer-create "*scratch*") 'norecord
)
649 (defun server-goto-toplevel (proc)
651 ;; If we're running isearch, we must abort it to allow Emacs to
652 ;; display the buffer and switch to it.
653 (dolist (buffer (buffer-list))
654 (with-current-buffer buffer
655 (when (bound-and-true-p isearch-mode
)
657 ;; Signaled by isearch-cancel.
658 (quit (message nil
)))
659 (when (> (recursion-depth) 0)
660 ;; We're inside a minibuffer already, so if the emacs-client is trying
661 ;; to open a frame on a new display, we might end up with an unusable
662 ;; frame because input from that display will be blocked (until exiting
663 ;; the minibuffer). Better exit this minibuffer right away.
664 ;; Similarly with recursive-edits such as the splash screen.
665 (run-with-timer 0 nil
(lexical-let ((proc proc
))
666 (lambda () (server-execute-continuation proc
))))
669 ;; We use various special properties on process objects:
670 ;; - `env' stores the info about the environment of the emacsclient process.
671 ;; - `continuation' is a no-arg function that we need to execute. It contains
672 ;; commands we wanted to execute in some earlier invocation of the process
673 ;; filter but that we somehow were unable to process at that time
674 ;; (e.g. because we first need to throw to the toplevel).
676 (defun server-execute-continuation (proc)
677 (let ((continuation (process-get proc
'continuation
)))
678 (process-put proc
'continuation nil
)
679 (if continuation
(ignore-errors (funcall continuation
)))))
681 (defun* server-process-filter
(proc string
)
682 "Process a request from the server to edit some files.
683 PROC is the server process. STRING consists of a sequence of
684 commands prefixed by a dash. Some commands have arguments;
685 these are &-quoted and need to be decoded by `server-unquote-arg'.
686 The filter parses and executes these commands.
688 To illustrate the protocol, here is an example command that
689 emacsclient sends to create a new X frame (note that the whole
690 sequence is sent on a single line):
692 -env HOME=/home/lorentey
694 ... lots of other -env commands
698 The following commands are accepted by the server:
701 Authenticate the client using the secret authentication string
705 An environment variable on the client side.
708 The current working directory of the client process.
711 Forbid the creation of new frames.
714 Request that the next frame created should not be
715 associated with this client.
718 Set the display name to open X frames on.
720 `-position LINE[:COLUMN]'
721 Go to the given line and column number
722 in the next file opened.
725 Load the given file in the current frame.
728 Evaluate EXPR as a Lisp expression and return the
729 result in -print commands.
734 `-tty DEVICENAME TYPE'
735 Open a new tty frame at the client.
738 Suspend this tty frame. The client sends this string in
739 response to SIGTSTP and SIGTTOU. The server must cease all I/O
740 on this tty until it gets a -resume command.
743 Resume this tty frame. The client sends this string when it
744 gets the SIGCONT signal and it is the foreground process on its
748 Do nothing, but put the comment in the server log.
749 Useful for debugging.
752 The following commands are accepted by the client:
755 Describes the process id of the Emacs process;
756 used to forward window change signals to it.
758 `-window-system-unsupported'
759 Signals that the server does not support creating X frames;
760 the client must try again with a tty frame.
763 Print STRING on stdout. Used to send values
767 Signal an error (but continue processing).
770 Suspend this terminal, i.e., stop the client process.
771 Sent when the user presses C-z."
772 (server-log (concat "Received " string
) proc
)
773 ;; First things first: let's check the authentication
774 (unless (process-get proc
:authenticated
)
775 (if (and (string-match "-auth \\([!-~]+\\)\n?" string
)
776 (equal (match-string 1 string
) (process-get proc
:auth-key
)))
778 (setq string
(substring string
(match-end 0)))
779 (process-put proc
:authenticated t
)
780 (server-log "Authentication successful" proc
))
781 (server-log "Authentication failed" proc
)
783 proc
(concat "-error " (server-quote-arg "Authentication failed")))
784 (delete-process proc
)
785 ;; We return immediately
786 (return-from server-process-filter
)))
787 (let ((prev (process-get proc
'previous-string
)))
789 (setq string
(concat prev string
))
790 (process-put proc
'previous-string nil
)))
793 (server-add-client proc
)
794 (if (not (string-match "\n" string
))
795 ;; Save for later any partial line that remains.
796 (when (> (length string
) 0)
797 (process-put proc
'previous-string string
))
799 ;; In earlier versions of server.el (where we used an `emacsserver'
800 ;; process), there could be multiple lines. Nowadays this is not
801 ;; supported any more.
802 (assert (eq (match-end 0) (length string
)))
803 (let ((request (substring string
0 (match-beginning 0)))
804 (coding-system (and default-enable-multibyte-characters
805 (or file-name-coding-system
806 default-file-name-coding-system
)))
807 nowait
; t if emacsclient does not want to wait for us.
808 frame
; The frame that was opened for the client (if any).
809 display
; Open the frame on this display.
810 dontkill
; t if the client should not be killed.
814 tty-name
;nil, `window-system', or the tty name.
818 command-line-args-left
820 ;; Remove this line from STRING.
821 (setq string
(substring string
(match-end 0)))
822 (setq command-line-args-left
823 (mapcar 'server-unquote-arg
(split-string request
" " t
)))
824 (while (setq arg
(pop command-line-args-left
))
826 ;; -version CLIENT-VERSION: obsolete at birth.
827 ((and (equal "-version" arg
) command-line-args-left
)
828 (pop command-line-args-left
))
830 ;; -nowait: Emacsclient won't wait for a result.
831 ((equal "-nowait" arg
) (setq nowait t
))
833 ;; -current-frame: Don't create frames.
834 ((equal "-current-frame" arg
) (setq use-current-frame t
))
837 ;; Open X frames on the given display instead of the default.
838 ((and (equal "-display" arg
) command-line-args-left
)
839 (setq display
(pop command-line-args-left
))
840 (if (zerop (length display
)) (setq display nil
)))
842 ;; -window-system: Open a new X frame.
843 ((equal "-window-system" arg
)
845 (setq tty-name
'window-system
))
847 ;; -resume: Resume a suspended tty frame.
848 ((equal "-resume" arg
)
849 (lexical-let ((terminal (process-get proc
'terminal
)))
852 (when (eq (terminal-live-p terminal
) t
)
853 (resume-tty terminal
)))
856 ;; -suspend: Suspend the client's frame. (In case we
857 ;; get out of sync, and a C-z sends a SIGTSTP to
859 ((equal "-suspend" arg
)
860 (lexical-let ((terminal (process-get proc
'terminal
)))
863 (when (eq (terminal-live-p terminal
) t
)
864 (suspend-tty terminal
)))
867 ;; -ignore COMMENT: Noop; useful for debugging emacsclient.
868 ;; (The given comment appears in the server log.)
869 ((and (equal "-ignore" arg
) command-line-args-left
871 (pop command-line-args-left
)))
873 ;; -tty DEVICE-NAME TYPE: Open a new tty frame at the client.
874 ((and (equal "-tty" arg
)
875 (cdr command-line-args-left
))
876 (setq tty-name
(pop command-line-args-left
)
877 tty-type
(pop command-line-args-left
)
878 dontkill
(or dontkill
879 (not use-current-frame
))))
881 ;; -position LINE[:COLUMN]: Set point to the given
882 ;; position in the next file.
883 ((and (equal "-position" arg
)
884 command-line-args-left
885 (string-match "\\+\\([0-9]+\\)\\(?::\\([0-9]+\\)\\)?"
886 (car command-line-args-left
)))
887 (setq arg
(pop command-line-args-left
))
889 (cons (string-to-number (match-string 1 arg
))
890 (string-to-number (or (match-string 2 arg
) "")))))
892 ;; -file FILENAME: Load the given file.
893 ((and (equal "-file" arg
)
894 command-line-args-left
)
895 (let ((file (pop command-line-args-left
)))
897 (setq file
(decode-coding-string file coding-system
)))
898 (setq file
(command-line-normalize-file-name file
))
899 (push (cons file filepos
) files
)
900 (server-log (format "New file: %s %s"
901 file
(or filepos
"")) proc
))
904 ;; -eval EXPR: Evaluate a Lisp expression.
905 ((and (equal "-eval" arg
)
906 command-line-args-left
)
907 (if use-current-frame
908 (setq use-current-frame
'always
))
909 (lexical-let ((expr (pop command-line-args-left
)))
911 (setq expr
(decode-coding-string expr coding-system
)))
912 (push (lambda () (server-eval-and-print expr proc
))
916 ;; -env NAME=VALUE: An environment variable.
917 ((and (equal "-env" arg
) command-line-args-left
)
918 (let ((var (pop command-line-args-left
)))
919 ;; XXX Variables should be encoded as in getenv/setenv.
920 (process-put proc
'env
921 (cons var
(process-get proc
'env
)))))
923 ;; -dir DIRNAME: The cwd of the emacsclient process.
924 ((and (equal "-dir" arg
) command-line-args-left
)
925 (setq dir
(pop command-line-args-left
))
927 (setq dir
(decode-coding-string dir coding-system
)))
928 (setq dir
(command-line-normalize-file-name dir
)))
931 (t (error "Unknown command: %s" arg
))))
935 ((and use-current-frame
936 (or (eq use-current-frame
'always
)
937 ;; We can't use the Emacs daemon's
940 (= (length (frame-list)) 1)
943 (setq tty-name nil tty-type nil
)
944 (if display
(server-select-display display
)))
945 ((eq tty-name
'window-system
)
946 (server-create-window-system-frame display nowait proc
))
947 ;; When resuming on a tty, tty-name is nil.
949 (server-create-tty-frame tty-name tty-type proc
))))
953 (lexical-let ((proc proc
)
962 (with-current-buffer (get-buffer-create server-buffer
)
963 ;; Use the same cwd as the emacsclient, if possible, so
964 ;; relative file names work correctly, even in `eval'.
965 (let ((default-directory
966 (if (and dir
(file-directory-p dir
))
967 dir default-directory
)))
968 (server-execute proc files nowait commands
969 dontkill frame tty-name
))))))
971 (when (or frame files
)
972 (server-goto-toplevel proc
))
974 (server-execute-continuation proc
))))
976 (error (server-return-error proc err
))))
978 (defun server-execute (proc files nowait commands dontkill frame tty-name
)
982 (run-hooks 'pre-command-hook
)
983 (prog1 (server-visit-files files proc nowait
)
984 (run-hooks 'post-command-hook
)))))
986 (mapc 'funcall
(nreverse commands
))
988 ;; Delete the client if necessary.
991 ;; Client requested nowait; return immediately.
992 (server-log "Close nowait client" proc
)
993 (server-delete-client proc
))
994 ((and (not dontkill
) (null buffers
))
995 ;; This client is empty; get rid of it immediately.
996 (server-log "Close empty client" proc
)
997 (server-delete-client proc
)))
999 ((or isearch-mode
(minibufferp))
1001 ((and frame
(null buffers
))
1002 (message "%s" (substitute-command-keys
1003 "When done with this frame, type \\[delete-frame]")))
1004 ((not (null buffers
))
1005 (server-switch-buffer (car buffers
) nil
(cdr (car files
)))
1006 (run-hooks 'server-switch-hook
)
1008 (message "%s" (substitute-command-keys
1009 "When done with a buffer, type \\[server-edit]")))))
1010 (when (and frame
(null tty-name
))
1011 (server-unselect-display frame
)))
1012 (error (server-return-error proc err
))))
1014 (defun server-return-error (proc err
)
1017 proc
(concat "-error " (server-quote-arg
1018 (error-message-string err
))))
1019 (server-log (error-message-string err
) proc
)
1020 (delete-process proc
)))
1022 (defun server-goto-line-column (line-col)
1023 "Move point to the position indicated in LINE-COL.
1024 LINE-COL should be a pair (LINE . COL)."
1026 (goto-line (car line-col
))
1027 (let ((column-number (cdr line-col
)))
1028 (when (> column-number
0)
1029 (move-to-column (1- column-number
))))))
1031 (defun server-visit-files (files proc
&optional nowait
)
1032 "Find FILES and return a list of buffers created.
1033 FILES is an alist whose elements are (FILENAME . FILEPOS)
1034 where FILEPOS can be nil or a pair (LINENUMBER . COLUMNNUMBER).
1035 PROC is the client that requested this operation.
1036 NOWAIT non-nil means this client is not waiting for the results,
1037 so don't mark these buffers specially, just visit them normally."
1038 ;; Bind last-nonmenu-event to force use of keyboard, not mouse, for queries.
1039 (let ((last-nonmenu-event t
) client-record
)
1040 ;; Restore the current buffer afterward, but not using save-excursion,
1041 ;; because we don't want to save point in this buffer
1042 ;; if it happens to be one of those specified by the server.
1043 (save-current-buffer
1044 (dolist (file files
)
1045 ;; If there is an existing buffer modified or the file is
1046 ;; modified, revert it. If there is an existing buffer with
1047 ;; deleted file, offer to write it.
1048 (let* ((minibuffer-auto-raise (or server-raise-frame
1049 minibuffer-auto-raise
))
1051 (obuf (get-file-buffer filen
)))
1052 (add-to-history 'file-name-history filen
)
1054 (set-buffer (find-file-noselect filen
))
1056 (cond ((file-exists-p filen
)
1057 (when (not (verify-visited-file-modtime obuf
))
1058 (revert-buffer t nil
)))
1061 (concat "File no longer exists: " filen
1062 ", write buffer to file? "))
1063 (write-file filen
))))
1064 (unless server-buffer-clients
1065 (setq server-existing-buffer t
)))
1066 (server-goto-line-column (cdr file
))
1067 (run-hooks 'server-visit-hook
))
1069 ;; When the buffer is killed, inform the clients.
1070 (add-hook 'kill-buffer-hook
'server-kill-buffer nil t
)
1071 (push proc server-buffer-clients
))
1072 (push (current-buffer) client-record
)))
1074 (process-put proc
'buffers
1075 (nconc (process-get proc
'buffers
) client-record
)))
1078 (defun server-buffer-done (buffer &optional for-killing
)
1079 "Mark BUFFER as \"done\" for its client(s).
1080 This buries the buffer, then returns a list of the form (NEXT-BUFFER KILLED).
1081 NEXT-BUFFER is another server buffer, as a suggestion for what to select next,
1082 or nil. KILLED is t if we killed BUFFER (typically, because it was visiting
1084 FOR-KILLING if non-nil indicates that we are called from `kill-buffer'."
1085 (let ((next-buffer nil
)
1087 (dolist (proc server-clients
)
1088 (let ((buffers (process-get proc
'buffers
)))
1090 (setq next-buffer
(nth 1 (memq buffer buffers
))))
1091 (when buffers
; Ignore bufferless clients.
1092 (setq buffers
(delq buffer buffers
))
1093 ;; Delete all dead buffers from PROC.
1096 (not (buffer-live-p b
))
1097 (setq buffers
(delq b buffers
))))
1098 (process-put proc
'buffers buffers
)
1099 ;; If client now has no pending buffers,
1100 ;; tell it that it is done, and forget it entirely.
1102 (server-log "Close" proc
)
1104 ;; `server-delete-client' might delete the client's
1105 ;; frames, which might change the current buffer. We
1106 ;; don't want that (bug#640).
1107 (save-current-buffer
1108 (server-delete-client proc
))
1109 (server-delete-client proc
))))))
1110 (when (and (bufferp buffer
) (buffer-name buffer
))
1111 ;; We may or may not kill this buffer;
1112 ;; if we do, do not call server-buffer-done recursively
1113 ;; from kill-buffer-hook.
1114 (let ((server-kill-buffer-running t
))
1115 (with-current-buffer buffer
1116 (setq server-buffer-clients nil
)
1117 (run-hooks 'server-done-hook
))
1118 ;; Notice whether server-done-hook killed the buffer.
1119 (if (null (buffer-name buffer
))
1121 ;; Don't bother killing or burying the buffer
1122 ;; when we are called from kill-buffer.
1124 (when (and (not killed
)
1125 server-kill-new-buffers
1126 (with-current-buffer buffer
1127 (not server-existing-buffer
)))
1129 (bury-buffer buffer
)
1130 (kill-buffer buffer
))
1132 (if (server-temp-file-p buffer
)
1134 (kill-buffer buffer
)
1136 (bury-buffer buffer
)))))))
1137 (list next-buffer killed
)))
1139 (defun server-temp-file-p (&optional buffer
)
1140 "Return non-nil if BUFFER contains a file considered temporary.
1141 These are files whose names suggest they are repeatedly
1142 reused to pass information to another program.
1144 The variable `server-temp-file-regexp' controls which filenames
1145 are considered temporary."
1146 (and (buffer-file-name buffer
)
1147 (string-match server-temp-file-regexp
(buffer-file-name buffer
))))
1149 (defun server-done ()
1150 "Offer to save current buffer, mark it as \"done\" for clients.
1151 This kills or buries the buffer, then returns a list
1152 of the form (NEXT-BUFFER KILLED). NEXT-BUFFER is another server buffer,
1153 as a suggestion for what to select next, or nil.
1154 KILLED is t if we killed BUFFER, which happens if it was created
1155 specifically for the clients and did not exist before their request for it."
1156 (when server-buffer-clients
1157 (if (server-temp-file-p)
1158 ;; For a temp file, save, and do make a non-numeric backup
1159 ;; (unless make-backup-files is nil).
1160 (let ((version-control nil
)
1161 (buffer-backed-up nil
))
1163 (when (and (buffer-modified-p)
1165 (y-or-n-p (concat "Save file " buffer-file-name
"? ")))
1167 (server-buffer-done (current-buffer))))
1169 ;; Ask before killing a server buffer.
1170 ;; It was suggested to release its client instead,
1171 ;; but I think that is dangerous--the client would proceed
1172 ;; using whatever is on disk in that file. -- rms.
1173 (defun server-kill-buffer-query-function ()
1174 "Ask before killing a server buffer."
1175 (or (not server-buffer-clients
)
1177 (dolist (proc server-buffer-clients res
)
1178 (when (and (memq proc server-clients
)
1179 (eq (process-status proc
) 'open
))
1181 (yes-or-no-p (format "Buffer `%s' still has clients; kill it? "
1182 (buffer-name (current-buffer))))))
1184 (defun server-kill-emacs-query-function ()
1185 "Ask before exiting Emacs if it has live clients."
1186 (or (not server-clients
)
1188 (dolist (proc server-clients live-client
)
1189 (when (memq t
(mapcar 'buffer-live-p
(process-get
1191 (setq live-client t
))))
1192 (yes-or-no-p "This Emacs session has clients; exit anyway? ")))
1194 (defvar server-kill-buffer-running nil
1195 "Non-nil while `server-kill-buffer' or `server-buffer-done' is running.")
1197 (defun server-kill-buffer ()
1198 "Remove the current buffer from its clients' buffer list.
1199 Designed to be added to `kill-buffer-hook'."
1200 ;; Prevent infinite recursion if user has made server-done-hook
1201 ;; call kill-buffer.
1202 (or server-kill-buffer-running
1203 (and server-buffer-clients
1204 (let ((server-kill-buffer-running t
))
1205 (when server-process
1206 (server-buffer-done (current-buffer) t
))))))
1208 (defun server-edit (&optional arg
)
1209 "Switch to next server editing buffer; say \"Done\" for current buffer.
1210 If a server buffer is current, it is marked \"done\" and optionally saved.
1211 The buffer is also killed if it did not exist before the clients asked for it.
1212 When all of a client's buffers are marked as \"done\", the client is notified.
1214 Temporary files such as MH <draft> files are always saved and backed up,
1215 no questions asked. (The variable `make-backup-files', if nil, still
1216 inhibits a backup; you can set it locally in a particular buffer to
1217 prevent a backup for it.) The variable `server-temp-file-regexp' controls
1218 which filenames are considered temporary.
1220 If invoked with a prefix argument, or if there is no server process running,
1221 starts server process and that is all. Invoked by \\[server-edit]."
1225 (not server-process
)
1226 (memq (process-status server-process
) '(signal exit
)))
1228 (server-clients (apply 'server-switch-buffer
(server-done)))
1229 (t (message "No server editing buffers exist"))))
1231 (defun server-switch-buffer (&optional next-buffer killed-one filepos
)
1232 "Switch to another buffer, preferably one that has a client.
1233 Arg NEXT-BUFFER is a suggestion; if it is a live buffer, use it.
1235 KILLED-ONE is t in a recursive call if we have already killed one
1236 temp-file server buffer. This means we should avoid the final
1237 \"switch to some other buffer\" since we've already effectively
1240 FILEPOS specifies a new buffer position for NEXT-BUFFER, if we
1241 visit NEXT-BUFFER in an existing window. If non-nil, it should
1242 be a cons cell (LINENUMBER . COLUMNNUMBER)."
1243 (if (null next-buffer
)
1245 (let ((rest server-clients
))
1246 (while (and rest
(not next-buffer
))
1247 (let ((proc (car rest
)))
1248 ;; Only look at frameless clients, or those in the selected
1250 (when (or (not (process-get proc
'frame
))
1251 (eq (process-get proc
'frame
) (selected-frame)))
1252 (setq next-buffer
(car (process-get proc
'buffers
))))
1253 (setq rest
(cdr rest
)))))
1254 (and next-buffer
(server-switch-buffer next-buffer killed-one
))
1255 (unless (or next-buffer killed-one
(window-dedicated-p (selected-window)))
1256 ;; (switch-to-buffer (other-buffer))
1257 (message "No server buffers remain to edit")))
1258 (if (not (buffer-live-p next-buffer
))
1259 ;; If NEXT-BUFFER is a dead buffer, remove the server records for it
1260 ;; and try the next surviving server buffer.
1261 (apply 'server-switch-buffer
(server-buffer-done next-buffer
))
1262 ;; OK, we know next-buffer is live, let's display and select it.
1263 (if (functionp server-window
)
1264 (funcall server-window next-buffer
)
1265 (let ((win (get-buffer-window next-buffer
0)))
1266 (if (and win
(not server-window
))
1267 ;; The buffer is already displayed: just reuse the
1268 ;; window. If FILEPOS is non-nil, use it to replace the
1269 ;; window's own value of point.
1272 (set-buffer next-buffer
)
1274 (server-goto-line-column filepos
)))
1275 ;; Otherwise, let's find an appropriate window.
1276 (cond ((window-live-p server-window
)
1277 (select-window server-window
))
1278 ((framep server-window
)
1279 (unless (frame-live-p server-window
)
1280 (setq server-window
(make-frame)))
1281 (select-window (frame-selected-window server-window
))))
1282 (when (window-minibuffer-p (selected-window))
1283 (select-window (next-window nil
'nomini
0)))
1284 ;; Move to a non-dedicated window, if we have one.
1285 (when (window-dedicated-p (selected-window))
1287 (get-window-with-predicate
1289 (and (not (window-dedicated-p w
))
1290 (equal (frame-terminal (window-frame w
))
1291 (frame-terminal (selected-frame)))))
1292 'nomini
'visible
(selected-window))))
1294 (switch-to-buffer next-buffer
)
1295 ;; After all the above, we might still have ended up with
1296 ;; a minibuffer/dedicated-window (if there's no other).
1297 (error (pop-to-buffer next-buffer
)))))))
1298 (when server-raise-frame
1299 (select-frame-set-input-focus (window-frame (selected-window))))))
1302 (defun server-save-buffers-kill-terminal (proc &optional arg
)
1303 ;; Called from save-buffers-kill-terminal in files.el.
1304 "Offer to save each buffer, then kill PROC.
1306 With prefix arg, silently save all file-visiting buffers, then kill.
1308 If emacsclient was started with a list of filenames to edit, then
1309 only these files will be asked to be saved."
1310 ;; save-buffers-kill-terminal occasionally calls us with proc set
1311 ;; to `nowait' (comes from the value of the `client' frame parameter).
1312 (when (processp proc
)
1313 (let ((buffers (process-get proc
'buffers
)))
1314 ;; If client is bufferless, emulate a normal Emacs session
1315 ;; exit and offer to save all buffers. Otherwise, offer to
1316 ;; save only the buffers belonging to the client.
1317 (save-some-buffers arg
1319 (lambda () (memq (current-buffer) buffers
))
1321 (server-delete-client proc
))))
1323 (define-key ctl-x-map
"#" 'server-edit
)
1325 (defun server-unload-function ()
1326 "Unload the server library."
1328 (substitute-key-definition 'server-edit nil ctl-x-map
)
1329 (save-current-buffer
1330 (dolist (buffer (buffer-list))
1332 (remove-hook 'kill-buffer-hook
'server-kill-buffer t
)))
1333 ;; continue standard unloading
1339 ;; arch-tag: 1f7ecb42-f00a-49f8-906d-61995d84c8d6
1340 ;;; server.el ends here