server.el 35.5 KB
Newer Older
1
;;; server.el --- Lisp code for GNU Emacs running as server process
Eric S. Raymond's avatar
Eric S. Raymond committed
2

3
;; Copyright (C) 1986,87,92,94,95,96,97,98,99,2000,01,02,03,2004
4
;;	 Free Software Foundation, Inc.
Eric S. Raymond's avatar
Eric S. Raymond committed
5

Eric S. Raymond's avatar
Eric S. Raymond committed
6
;; Author: William Sommerfeld <wesommer@athena.mit.edu>
Richard M. Stallman's avatar
Richard M. Stallman committed
7
;; Maintainer: FSF
Eric S. Raymond's avatar
Eric S. Raymond committed
8
;; Keywords: processes
Eric S. Raymond's avatar
Eric S. Raymond committed
9

root's avatar
root committed
10
;; Changes by peck@sun.com and by rms.
11
;; Overhaul by Karoly Lorentey <lorentey@elte.hu> for multi-tty support.
root's avatar
root committed
12 13 14 15 16

;; This file is part of GNU Emacs.

;; GNU Emacs is free software; you can redistribute it and/or modify
;; it under the terms of the GNU General Public License as published by
Eric S. Raymond's avatar
Eric S. Raymond committed
17
;; the Free Software Foundation; either version 2, or (at your option)
root's avatar
root committed
18 19 20 21 22 23 24 25
;; any later version.

;; GNU Emacs is distributed in the hope that it will be useful,
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
;; GNU General Public License for more details.

;; You should have received a copy of the GNU General Public License
Erik Naggum's avatar
Erik Naggum committed
26 27 28
;; along with GNU Emacs; see the file COPYING.  If not, write to the
;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
;; Boston, MA 02111-1307, USA.
root's avatar
root committed
29

Eric S. Raymond's avatar
Eric S. Raymond committed
30
;;; Commentary:
root's avatar
root committed
31

Erik Naggum's avatar
Erik Naggum committed
32 33
;; This Lisp code is run in Emacs when it is to operate as
;; a server for other processes.
root's avatar
root committed
34

Erik Naggum's avatar
Erik Naggum committed
35
;; Load this library and do M-x server-edit to enable Emacs as a server.
36 37 38
;; Emacs opens up a socket for communication with clients.  If there are no
;; client buffers to edit, server-edit acts like (switch-to-buffer
;; (other-buffer))
root's avatar
root committed
39

Erik Naggum's avatar
Erik Naggum committed
40 41 42 43
;; When some other program runs "the editor" to edit a file,
;; "the editor" can be the Emacs client program ../lib-src/emacsclient.
;; This program transmits the file names to Emacs through
;; the server subprocess, and Emacs visits them and lets you edit them.
root's avatar
root committed
44

Erik Naggum's avatar
Erik Naggum committed
45
;; Note that any number of clients may dispatch files to emacs to be edited.
root's avatar
root committed
46

Erik Naggum's avatar
Erik Naggum committed
47
;; When you finish editing a Server buffer, again call server-edit
48 49
;; to mark that buffer as done for the client and switch to the next
;; Server buffer.  When all the buffers for a client have been edited
Erik Naggum's avatar
Erik Naggum committed
50
;; and exited with server-edit, the client "editor" will return
51
;; to the program that invoked it.
root's avatar
root committed
52

Erik Naggum's avatar
Erik Naggum committed
53 54 55 56
;; Your editing commands and Emacs's display output go to and from
;; the terminal in the usual way.  Thus, server operation is possible
;; only when Emacs can talk to the terminal at the time you invoke
;; the client.  This is possible in four cases:
root's avatar
root committed
57

Erik Naggum's avatar
Erik Naggum committed
58 59
;; 1. On a window system, where Emacs runs in one window and the
;; program that wants to use "the editor" runs in another.
root's avatar
root committed
60

Erik Naggum's avatar
Erik Naggum committed
61 62
;; 2. On a multi-terminal system, where Emacs runs on one terminal and the
;; program that wants to use "the editor" runs on another.
root's avatar
root committed
63

Erik Naggum's avatar
Erik Naggum committed
64 65
;; 3. When the program that wants to use "the editor" is running
;; as a subprocess of Emacs.
root's avatar
root committed
66

Erik Naggum's avatar
Erik Naggum committed
67 68 69 70 71
;; 4. On a system with job control, when Emacs is suspended, the program
;; that wants to use "the editor" will stop and display
;; "Waiting for Emacs...".  It can then be suspended, and Emacs can be
;; brought into the foreground for editing.  When done editing, Emacs is
;; suspended again, and the client program is brought into the foreground.
root's avatar
root committed
72

73 74
;; The buffer local variable "server-buffer-clients" lists
;; the clients who are waiting for this buffer to be edited.
Erik Naggum's avatar
Erik Naggum committed
75 76
;; The global variable "server-clients" lists all the waiting clients,
;; and which files are yet to be edited for each.
Eric S. Raymond's avatar
Eric S. Raymond committed
77 78

;;; Code:
79 80 81

(eval-when-compile (require 'cl))

Richard M. Stallman's avatar
Richard M. Stallman committed
82 83 84 85 86
(defgroup server nil
  "Emacs running as a server process."
  :group 'external)

(defcustom server-visit-hook nil
87
  "*Hook run when visiting a file for the Emacs server."
Richard M. Stallman's avatar
Richard M. Stallman committed
88
  :group 'server
89
  :type 'hook)
Richard M. Stallman's avatar
Richard M. Stallman committed
90 91

(defcustom server-switch-hook nil
92
  "*Hook run when switching to a buffer for the Emacs server."
Richard M. Stallman's avatar
Richard M. Stallman committed
93
  :group 'server
94
  :type 'hook)
Richard M. Stallman's avatar
Richard M. Stallman committed
95 96

(defcustom server-done-hook nil
97
  "*Hook run when done editing a buffer for the Emacs server."
Richard M. Stallman's avatar
Richard M. Stallman committed
98
  :group 'server
99
  :type 'hook)
100

101 102
(defvar server-process nil
  "The current server process.")
root's avatar
root committed
103 104 105

(defvar server-clients nil
  "List of current server clients.
Karoly Lorentey's avatar
Karoly Lorentey committed
106 107
Each element is (PROC PROPERTIES...) where PROC is a process object,
and PROPERTIES is an association list of client properties.")
Karoly Lorentey's avatar
Karoly Lorentey committed
108

root's avatar
root committed
109
(defvar server-buffer-clients nil
110
  "List of client ids for clients requesting editing of current buffer.")
111
(make-variable-buffer-local 'server-buffer-clients)
root's avatar
root committed
112 113 114
;; Changing major modes should not erase this local.
(put 'server-buffer-clients 'permanent-local t)

Dave Love's avatar
Dave Love committed
115 116
(defcustom server-window nil
  "*Specification of the window to use for selecting Emacs server buffers.
117
If nil, use the selected window.
118
If it is a function, it should take one argument (a buffer) and
Dave Love's avatar
Dave Love committed
119 120 121 122 123 124 125 126 127 128 129 130 131 132
display and select it.  A common value is `pop-to-buffer'.
If it is a window, use that.
If it is a frame, use the frame's selected window.

It is not meaningful to set this to a specific frame or window with Custom.
Only programs can do so."
  :group 'server
  :version "21.4"
  :type '(choice (const :tag "Use selected window"
			:match (lambda (widget value)
				 (not (functionp value)))
			nil)
		 (function-item :tag "Use pop-to-buffer" pop-to-buffer)
		 (function :tag "Other function")))
133

Richard M. Stallman's avatar
Richard M. Stallman committed
134
(defcustom server-temp-file-regexp "^/tmp/Re\\|/draft$"
Dave Love's avatar
Dave Love committed
135 136 137
  "*Regexp matching names of temporary files.
These are deleted and reused after each edit by the programs that
invoke the Emacs server."
Richard M. Stallman's avatar
Richard M. Stallman committed
138 139
  :group 'server
  :type 'regexp)
root's avatar
root committed
140

141 142 143
(defcustom server-kill-new-buffers t
  "*Whether to kill buffers when done with them.
If non-nil, kill a buffer unless it already existed before editing
144
it with Emacs server.  If nil, kill only buffers as specified by
145 146 147 148 149 150 151 152
`server-temp-file-regexp'.
Please note that only buffers are killed that still have a client,
i.e. buffers visited which \"emacsclient --no-wait\" are never killed in
this way."
  :group 'server
  :type 'boolean
  :version "21.1")

root's avatar
root committed
153 154 155
(or (assq 'server-buffer-clients minor-mode-alist)
    (setq minor-mode-alist (cons '(server-buffer-clients " Server") minor-mode-alist)))

156
(defvar server-existing-buffer nil
157
  "Non-nil means the buffer existed before the server was asked to visit it.
158
This means that the server should not kill the buffer when you say you
159
are done with it in the server.")
160 161
(make-variable-buffer-local 'server-existing-buffer)

Stefan Monnier's avatar
Stefan Monnier committed
162 163
(defvar server-name "server")

164 165 166
(defvar server-socket-dir nil
  "The directory in which to place the server socket.
Initialized by `server-start'.")
167

Karoly Lorentey's avatar
Karoly Lorentey committed
168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211
(defun server-client (proc)
  "Return the Emacs client corresponding to PROC.
PROC must be a process object.
The car of the result is PROC; the cdr is an association list.
See `server-client-get' and `server-client-set'."
  (assq proc server-clients))

(defun server-client-get (client property)
  "Get the value of PROPERTY in CLIENT.
CLIENT may be a process object, or a client returned by `server-client'.
Return nil if CLIENT has no such property."
  (or (listp client) (setq client (server-client client)))
  (cdr (assq property (cdr client))))

(defun server-client-set (client property value)
  "Set the PROPERTY to VALUE in CLIENT, and return VALUE.
CLIENT may be a process object, or a client returned by `server-client'."
  (let (p proc)
    (if (listp client)
	(setq proc (car client))
      (setq proc client
	    client (server-client client)))
    (setq p (assq property client))
    (cond
     (p (setcdr p value))
     (client (setcdr client (cons (cons property value) (cdr client))))
     (t (setq server-clients
	      `((,proc (,property . ,value)) . ,server-clients))))
    value))

(defun server-clients-with (property value)
  "Return a list of clients with PROPERTY set to VALUE."
  (let (result)
    (dolist (client server-clients result)
      (when (equal value (server-client-get client property))
	(setq result (cons (car client) result))))))

(defun server-add-client (proc)
  "Create a client for process PROC, if it doesn't already have one.
New clients have no properties."
  (unless (server-client proc)
    (setq server-clients (cons (cons proc nil)
			       server-clients))))

212 213 214 215
(defun server-delete-client (client &optional noframe)
  "Delete CLIENT, including its buffers, displays and frames.
If NOFRAME is non-nil, let the frames live.  (To be used from
`delete-frame-functions'."
Karoly Lorentey's avatar
Karoly Lorentey committed
216 217 218 219 220 221 222 223 224
  ;; Force a new lookup of client (prevents infinite recursion).
  (setq client (server-client
		(if (listp client) (car client) client)))
  (let ((proc (car client))
	(buffers (server-client-get client 'buffers)))
    (when client
      (setq server-clients (delq client server-clients))

      (dolist (buf buffers)
225 226 227 228 229 230 231 232 233 234
	(when (buffer-live-p buf)
	  (with-current-buffer buf
	    ;; Remove PROC from the clients of each buffer.
	    (setq server-buffer-clients (delq proc server-buffer-clients))
	    ;; Kill the buffer if necessary.
	    (when (and (null server-buffer-clients)
		       (or (and server-kill-new-buffers
				(not server-existing-buffer))
			   (server-temp-file-p)))
	      (kill-buffer (current-buffer))))))
Karoly Lorentey's avatar
Karoly Lorentey committed
235 236 237

      ;; Delete the client's tty.
      (let ((tty (server-client-get client 'tty)))
238 239
	(when (and tty (server-tty-live-p tty))
	  (delete-tty tty)))
Karoly Lorentey's avatar
Karoly Lorentey committed
240 241

      ;; Delete the client's frames.
242 243 244 245 246
      (unless noframe
	(dolist (frame (frame-list))
	  (if (and (frame-live-p frame)
		   (equal (car client) (frame-parameter frame 'client)))
	      (delete-frame frame))))
Karoly Lorentey's avatar
Karoly Lorentey committed
247 248 249 250 251 252 253

      ;; Delete the client's process.
      (if (eq (process-status (car client)) 'open)
	  (delete-process (car client)))

      (server-log "Deleted" proc))))

254
(defun server-log (string &optional client)
Dave Love's avatar
Dave Love committed
255
  "If a *server* buffer exists, write STRING to it for logging purposes."
root's avatar
root committed
256
  (if (get-buffer "*server*")
257
      (with-current-buffer "*server*"
root's avatar
root committed
258
	(goto-char (point-max))
259
	(insert (current-time-string)
Karoly Lorentey's avatar
Karoly Lorentey committed
260 261 262 263
		(cond
		 ((null client) " ")
		 ((listp client) (format " %s: " (car client)))
		 (t (format " %s: " client)))
264
		string)
265
	(or (bolp) (newline)))))
root's avatar
root committed
266

267 268 269 270 271 272 273 274
(defun server-tty-live-p (tty)
  "Return non-nil if the tty device named TTY has a live frame."
  (let (result)
    (dolist (frame (frame-list) result)
      (when (and (eq (frame-live-p frame) t)
		 (equal (frame-tty-name frame) tty))
	(setq result t)))))

root's avatar
root committed
275
(defun server-sentinel (proc msg)
Karoly Lorentey's avatar
Karoly Lorentey committed
276 277 278
  "The process sentinel for Emacs server connections."
  (server-log (format "Status changed to %s: %s" (process-status proc) msg) proc)
  (server-delete-client proc))
279

280
(defun server-handle-delete-tty (tty)
281
  "Delete the client connection when the emacsclient terminal device is closed."
Karoly Lorentey's avatar
Karoly Lorentey committed
282 283 284
  (dolist (proc (server-clients-with 'tty tty))
    (server-log (format "server-handle-delete-tty, tty %s" tty) proc)
    (server-delete-client proc)))
285

286 287
(defun server-handle-delete-frame (frame)
  "Delete the client connection when the emacsclient frame is deleted."
Karoly Lorentey's avatar
Karoly Lorentey committed
288
  (let ((proc (frame-parameter frame 'client)))
289 290 291
    (when (and proc (window-system frame))
      ;; (Closing a terminal frame must not trigger a delete;
      ;; we must wait for delete-tty-after-functions.)
Karoly Lorentey's avatar
Karoly Lorentey committed
292
      (server-log (format "server-handle-delete-frame, frame %s" frame) proc)
293
      (server-delete-client proc 'noframe)))) ; Let delete-frame delete the frame later.
Karoly Lorentey's avatar
Karoly Lorentey committed
294 295 296 297 298 299

(defun server-handle-suspend-tty (tty)
  "Notify the emacsclient process to suspend itself when its tty device is suspended."
  (dolist (proc (server-clients-with 'tty tty))
    (server-log (format "server-handle-suspend-tty, tty %s" tty) proc)
    (process-send-string proc "-suspend \n")))
300

301 302 303 304 305 306 307 308 309 310 311
(defun server-select-display (display)
  ;; If the current frame is on `display' we're all set.
  (unless (equal (frame-parameter (selected-frame) 'display) display)
    ;; Otherwise, look for an existing frame there and select it.
    (dolist (frame (frame-list))
      (when (equal (frame-parameter frame 'display) display)
	(select-frame frame)))
    ;; If there's no frame on that display yet, create a dummy one
    ;; and select it.
    (unless (equal (frame-parameter (selected-frame) 'display) display)
      (select-frame
312
       (make-frame-on-display display)))))
313 314 315 316 317
	;; This frame is only there in place of an actual "current display"
	;; setting, so we want it to be as unobtrusive as possible.  That's
	;; what the invisibility is for.  The minibuffer setting is so that
	;; we don't end up displaying a buffer in it (which noone would
	;; notice).
318 319
        ;; XXX I have found this behaviour to be surprising and annoying. -- Lorentey
	;; '((visibility . nil) (minibuffer . only)))))))
320

321
(defun server-unquote-arg (arg)
Karoly Lorentey's avatar
Karoly Lorentey committed
322
  "Remove &-quotation from ARG."
323 324 325 326 327 328 329 330
  (replace-regexp-in-string
   "&." (lambda (s)
	  (case (aref s 1)
	    (?& "&")
	    (?- "-")
	    (?n "\n")
	    (t " ")))
   arg t t))
root's avatar
root committed
331

332
(defun server-quote-arg (arg)
Karoly Lorentey's avatar
Karoly Lorentey committed
333
  "In ARG, insert a & before each &, each space, each newline, and -.
334 335 336 337 338 339 340 341 342 343 344
Change spaces to underscores, too, so that the return value never
contains a space."
  (replace-regexp-in-string
   "[-&\n ]" (lambda (s)
	       (case (aref s 0)
		 (?& "&&")
		 (?- "&-")
		 (?\n "&n")
		 (?\s "&_")))
   arg t t))

345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360
(defun server-ensure-safe-dir (dir)
  "Make sure DIR is a directory with no race-condition issues.
Creates the directory if necessary and makes sure:
- there's no symlink involved
- it's owned by us
- it's not readable/writable by anybody else."
  (setq dir (directory-file-name dir))
  (let ((attrs (file-attributes dir)))
    (unless attrs
      (letf (((default-file-modes) ?\700)) (make-directory dir))
      (setq attrs (file-attributes dir)))
    ;; Check that it's safe for use.
    (unless (and (eq t (car attrs)) (eq (nth 2 attrs) (user-uid))
		 (zerop (logand ?\077 (file-modes dir))))
      (error "The directory %s is unsafe" dir))))

Roland McGrath's avatar
Roland McGrath committed
361
;;;###autoload
root's avatar
root committed
362 363 364 365
(defun server-start (&optional leave-dead)
  "Allow this Emacs process to be a server for client processes.
This starts a server communications subprocess through which
client \"editors\" can send your editing commands to this Emacs job.
Richard M. Stallman's avatar
Richard M. Stallman committed
366
To use the server, set up the program `emacsclient' in the
root's avatar
root committed
367 368 369 370
Emacs distribution as your standard \"editor\".

Prefix arg means just kill any existing server communications subprocess."
  (interactive "P")
371 372 373
  ;; It is safe to get the user id now.
  (setq server-socket-dir (or server-socket-dir
			      (format "/tmp/emacs%d" (user-uid))))
374
  ;; Make sure there is a safe directory in which to place the socket.
Stefan Monnier's avatar
Stefan Monnier committed
375
  (server-ensure-safe-dir server-socket-dir)
root's avatar
root committed
376
  ;; kill it dead!
377 378
  (if server-process
      (condition-case () (delete-process server-process) (error nil)))
379
  ;; Delete the socket files made by previous server invocations.
Stefan Monnier's avatar
Stefan Monnier committed
380 381 382
  (condition-case ()
      (delete-file (expand-file-name server-name server-socket-dir))
    (error nil))
383
  ;; If this Emacs already had a server, clear out associated status.
root's avatar
root committed
384
  (while server-clients
Karoly Lorentey's avatar
Karoly Lorentey committed
385
    (server-delete-client (car server-clients)))
386
  (unless leave-dead
root's avatar
root committed
387 388
    (if server-process
	(server-log (message "Restarting server")))
Stefan Monnier's avatar
Stefan Monnier committed
389
    (letf (((default-file-modes) ?\700))
Karoly Lorentey's avatar
Karoly Lorentey committed
390 391 392 393 394
      (add-hook 'delete-tty-after-functions 'server-handle-delete-tty)
      (add-hook 'suspend-tty-functions 'server-handle-suspend-tty)
      (add-hook 'delete-frame-functions 'server-handle-delete-frame)
      (add-hook 'kill-buffer-query-functions 'server-kill-buffer-query-function)
      (add-hook 'kill-emacs-query-functions 'server-kill-emacs-query-function)
Stefan Monnier's avatar
Stefan Monnier committed
395 396 397
      (setq server-process
	    (make-network-process
	     :name "server" :family 'local :server t :noquery t
Stefan Monnier's avatar
Stefan Monnier committed
398
	     :service (expand-file-name server-name server-socket-dir)
Stefan Monnier's avatar
Stefan Monnier committed
399 400 401 402 403
	     :sentinel 'server-sentinel :filter 'server-process-filter
	     ;; We must receive file names without being decoded.
	     ;; Those are decoded by server-process-filter according
	     ;; to file-name-coding-system.
	     :coding 'raw-text)))))
Dave Love's avatar
Dave Love committed
404 405 406 407 408 409 410 411 412 413 414 415 416

;;;###autoload
(define-minor-mode server-mode
  "Toggle Server mode.
With ARG, turn Server mode on if ARG is positive, off otherwise.
Server mode runs a process that accepts commands from the
`emacsclient' program.  See `server-start' and Info node `Emacs server'."
  :global t
  :group 'server
  :version "21.4"
  ;; Fixme: Should this check for an existing server socket and do
  ;; nothing if there is one (for multiple Emacs sessions)?
  (server-start (not server-mode)))
root's avatar
root committed
417 418

(defun server-process-filter (proc string)
Dave Love's avatar
Dave Love committed
419 420
  "Process a request from the server to edit some files.
PROC is the server process.  Format of STRING is \"PATH PATH PATH... \\n\"."
421
  (server-log string proc)
422 423 424 425
  (let ((prev (process-get proc 'previous-string)))
    (when prev
      (setq string (concat prev string))
      (process-put proc 'previous-string nil)))
426
  (condition-case err
427
      (progn
Karoly Lorentey's avatar
Karoly Lorentey committed
428
	(server-add-client proc)
429 430 431 432 433 434 435
	;; If the input is multiple lines,
	;; process each line individually.
	(while (string-match "\n" string)
	  (let ((request (substring string 0 (match-beginning 0)))
		(coding-system (and default-enable-multibyte-characters
				    (or file-name-coding-system
					default-file-name-coding-system)))
Karoly Lorentey's avatar
Karoly Lorentey committed
436 437 438 439
		(client (server-client proc))
		nowait ; t if emacsclient does not want to wait for us.
		frame ; The frame that was opened for the client (if any).
		display ; Open the frame on this display.
440 441 442 443 444 445
		dontkill       ; t if the client should not be killed.
		(files nil)
		(lineno 1)
		(columnno 0))
	    ;; Remove this line from STRING.
	    (setq string (substring string (match-end 0)))
Karoly Lorentey's avatar
Karoly Lorentey committed
446
	    (while (string-match " *[^ ]* " request)
447 448 449
	      (let ((arg (substring request (match-beginning 0) (1- (match-end 0)))))
		(setq request (substring request (match-end 0)))
		(cond
Karoly Lorentey's avatar
Karoly Lorentey committed
450 451 452 453
		 ;; -version CLIENT-VERSION:
		 ;; Check version numbers, signal an error if there is a mismatch.
		 ((and (equal "-version" arg)
		       (string-match "\\([0-9.]+\\) " request))
454
		  (let* ((client-version (match-string 1 request))
Karoly Lorentey's avatar
Karoly Lorentey committed
455 456
			 (truncated-emacs-version
			  (substring emacs-version 0 (length client-version))))
457 458 459 460
		    (setq request (substring request (match-end 0)))
		    (if (equal client-version truncated-emacs-version)
			(progn
			  (process-send-string proc "-good-version \n")
Karoly Lorentey's avatar
Karoly Lorentey committed
461 462 463 464
			  (server-client-set client 'version client-version))
		      (error (concat "Version mismatch: Emacs is "
				     truncated-emacs-version
				     ", emacsclient is " client-version)))))
465

Karoly Lorentey's avatar
Karoly Lorentey committed
466
		 ;; -nowait:  Emacsclient won't wait for a result.
467 468
		 ((equal "-nowait" arg) (setq nowait t))

Karoly Lorentey's avatar
Karoly Lorentey committed
469 470
		 ;; -display DISPLAY:
		 ;; Open X frames on the given instead of the default.
471 472 473 474
		 ((and (equal "-display" arg) (string-match "\\([^ ]*\\) " request))
		  (setq display (match-string 1 request)
			request (substring request (match-end 0))))

Karoly Lorentey's avatar
Karoly Lorentey committed
475
		 ;; -window-system:  Open a new X frame.
476
		 ((equal "-window-system" arg)
Karoly Lorentey's avatar
Karoly Lorentey committed
477
		  (unless (server-client-get client 'version)
478
		    (error "Protocol error; make sure to use the correct version of emacsclient"))
Karoly Lorentey's avatar
Karoly Lorentey committed
479 480 481 482
		  (setq frame (make-frame-on-display
			       (or display
				   (frame-parameter nil 'display)
				   (getenv "DISPLAY")
483 484 485 486 487
				   (error "Please specify display"))
			       (list (cons 'client proc))))
		  ;; XXX We need to ensure the client parameter is
		  ;; really set because Emacs forgets initialization
		  ;; parameters for X frames at the moment.
488
		  (modify-frame-parameters frame (list (cons 'client proc)))
Karoly Lorentey's avatar
Karoly Lorentey committed
489 490 491 492 493
		  (select-frame frame)
		  (server-client-set client 'frame frame)
		  (setq dontkill t))

		 ;; -resume:  Resume a suspended tty frame.
494
		 ((equal "-resume" arg)
Karoly Lorentey's avatar
Karoly Lorentey committed
495
		  (let ((tty (server-client-get client 'tty)))
496 497 498
		    (setq dontkill t)
		    (when tty (resume-tty tty))))

Karoly Lorentey's avatar
Karoly Lorentey committed
499 500 501
		 ;; -suspend:  Suspend the client's frame.  (In case we
		 ;; get out of sync, and a C-z sends a SIGTSTP to
		 ;; emacsclient.)
502
		 ((equal "-suspend" arg)
Karoly Lorentey's avatar
Karoly Lorentey committed
503
		  (let ((tty (server-client-get client 'tty)))
504 505 506
		    (setq dontkill t)
		    (when tty (suspend-tty tty))))

Karoly Lorentey's avatar
Karoly Lorentey committed
507 508
		 ;; -ignore COMMENT:  Noop; useful for debugging emacsclient.
		 ;; (The given comment appears in the server log.)
509 510 511 512
		 ((and (equal "-ignore" arg) (string-match "\\([^ ]*\\) " request))
		  (setq dontkill t
			request (substring request (match-end 0))))

Karoly Lorentey's avatar
Karoly Lorentey committed
513
		 ;; -tty DEVICE-NAME TYPE:  Open a new tty frame at the client.
514 515 516 517
		 ((and (equal "-tty" arg) (string-match "\\([^ ]*\\) \\([^ ]*\\) " request))
		  (let ((tty (server-unquote-arg (match-string 1 request)))
			(type (server-unquote-arg (match-string 2 request))))
		    (setq request (substring request (match-end 0)))
Karoly Lorentey's avatar
Karoly Lorentey committed
518 519
		    (unless (server-client-get client 'version)
		      (error "Protocol error; make sure you use the correct version of emacsclient"))
520
		    (setq frame (make-frame-on-tty tty type (list (cons 'client proc))))
Karoly Lorentey's avatar
Karoly Lorentey committed
521 522 523
		    (select-frame frame)
		    (server-client-set client 'frame frame)
		    (server-client-set client 'tty (frame-tty-name frame))
524 525
		    ;; Set up display for the remote locale.
		    (configure-display-for-locale)
Karoly Lorentey's avatar
Karoly Lorentey committed
526 527 528 529 530
		    ;; Reply with our pid.
		    (process-send-string proc (concat "-emacs-pid " (number-to-string (emacs-pid)) "\n"))
		    (setq dontkill t)))

		 ;; -position LINE:  Go to the given line in the next file.
531 532 533 534
		 ((and (equal "-position" arg) (string-match "\\(\\+[0-9]+\\) " request))
		  (setq request (substring request (match-end 0))
			lineno (string-to-int (substring (match-string 1 request) 1))))

Karoly Lorentey's avatar
Karoly Lorentey committed
535
		 ;; -position LINE:COLUMN:  Set point to the given position in the next file.
536 537 538 539 540
		 ((and (equal "-position" arg) (string-match "\\+\\([0-9]+\\):\\([0-9]+\\) " request))
		  (setq request (substring request (match-end 0))
			lineno (string-to-int (match-string 1 request))
			columnno (string-to-int (match-string 2 request))))

Karoly Lorentey's avatar
Karoly Lorentey committed
541
		 ;; -file FILENAME:  Load the given file.
542 543 544 545 546 547 548 549 550 551
		 ((and (equal "-file" arg) (string-match "\\([^ ]+\\) " request))
		  (let ((file (server-unquote-arg (match-string 1 request))))
		    (setq request (substring request (match-end 0)))
		    (if coding-system
			(setq file (decode-coding-string file coding-system)))
		    (setq file (command-line-normalize-file-name file))
		    (push (list file lineno columnno) files))
		  (setq lineno 1
			columnno 0))

Karoly Lorentey's avatar
Karoly Lorentey committed
552
		 ;; -eval EXPR:  Evaluate a Lisp expression.
553 554 555 556 557 558
		 ((and (equal "-eval" arg) (string-match "\\([^ ]+\\) " request))
		  (let ((expr (server-unquote-arg (match-string 1 request))))
		    (setq request (substring request (match-end 0)))
		    (if coding-system
			(setq expr (decode-coding-string expr coding-system)))
		    (let ((v (eval (car (read-from-string expr)))))
Karoly Lorentey's avatar
Karoly Lorentey committed
559
		      (when (and (not frame) v)
560 561 562 563
			(with-temp-buffer
			  (let ((standard-output (current-buffer)))
			    (pp v)
			    (process-send-string proc "-print ")
564 565 566 567 568 569 570 571
			    (process-send-string
			     proc (server-quote-arg
				   (buffer-substring-no-properties (point-min)
								   (point-max))))
			    (process-send-string proc "\n")))))
		    (setq lineno 1
			  columnno 0)))

Karoly Lorentey's avatar
Karoly Lorentey committed
572 573 574 575 576 577 578 579 580 581 582 583 584
		 ;; -env NAME VALUE:  An environment variable.
		 ((and (equal "-env" arg) (string-match "\\([^ ]+\\) \\([^ ]+\\) " request))
		  (let ((name (server-unquote-arg (match-string 1 request)))
			(value (server-unquote-arg (match-string 2 request))))
		    (when coding-system
			(setq name (decode-coding-string name coding-system))
			(setq value (decode-coding-string value coding-system)))
		    (setq request (substring request (match-end 0)))
		    (server-client-set
		     client 'environment
		     (cons (cons name value)
			   (server-client-get client 'environment)))))

585 586 587
		 ;; Unknown command.
		 (t (error "Unknown command: %s" arg)))))

588 589 590 591
	    (when files
	      (run-hooks 'pre-command-hook)
	      (server-visit-files files client nowait)
	      (run-hooks 'post-command-hook))
592 593 594 595

	    ;; Delete the client if necessary.
	    (cond
	     (nowait
Karoly Lorentey's avatar
Karoly Lorentey committed
596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619
	      ;; Client requested nowait; return immediately.
	      (server-log "Close nowait client" proc)
	      (server-delete-client proc))
	     ((and (not dontkill)
		   (null (server-client-get client 'buffers)))
	      ;; This client is empty; get rid of it immediately.
	      (server-log "Close empty client" proc)
	      (server-delete-client proc))
	     (t
	      (let ((buffers (server-client-get client 'buffers)))
		(when buffers
		  ;; We visited some buffer for this client.
		  (cond
		   ((or isearch-mode (minibufferp))
		    nil)
		   ((and frame (null buffers))
		    (message (substitute-command-keys
			      "When done with this frame, type \\[delete-frame]")))
		   ((not (null buffers))
		    (server-switch-buffer (car buffers))
		    (run-hooks 'server-switch-hook)
		    (unless nowait
		      (message (substitute-command-keys
				"When done with a buffer, type \\[server-edit]")))))))))))
620

621 622 623 624 625 626
	;; Save for later any partial line that remains.
	(when (> (length string) 0)
	  (process-put proc 'previous-string string)))
    ;; condition-case
    (error (ignore-errors
	     (process-send-string
627
	      proc (concat "-error " (server-quote-arg (error-message-string err))))
628 629 630
	     (setq string "")
	     (server-log (error-message-string err) proc)
	     (delete-process proc)))))
root's avatar
root committed
631

632 633 634 635 636 637
(defun server-goto-line-column (file-line-col)
  (goto-line (nth 1 file-line-col))
  (let ((column-number (nth 2 file-line-col)))
    (if (> column-number 0)
	(move-to-column (1- column-number)))))

638
(defun server-visit-files (files client &optional nowait)
639
  "Find FILES and return the list CLIENT with the buffers nconc'd.
640
FILES is an alist whose elements are (FILENAME LINENUMBER COLUMNNUMBER).
641 642
NOWAIT non-nil means this client is not waiting for the results,
so don't mark these buffers specially, just visit them normally."
643
  ;; Bind last-nonmenu-event to force use of keyboard, not mouse, for queries.
644
  (let ((last-nonmenu-event t) client-record)
645 646 647
    ;; Restore the current buffer afterward, but not using save-excursion,
    ;; because we don't want to save point in this buffer
    ;; if it happens to be one of those specified by the server.
648 649 650 651 652 653 654 655 656 657 658 659 660 661 662
    (save-current-buffer
      (dolist (file files)
	;; If there is an existing buffer modified or the file is
	;; modified, revert it.  If there is an existing buffer with
	;; deleted file, offer to write it.
	(let* ((filen (car file))
	       (obuf (get-file-buffer filen)))
	  (push filen file-name-history)
	  (if (and obuf (set-buffer obuf))
	      (progn
		(cond ((file-exists-p filen)
		       (if (not (verify-visited-file-modtime obuf))
			   (revert-buffer t nil)))
		      (t
		       (if (y-or-n-p
Karoly Lorentey's avatar
Karoly Lorentey committed
663
			    (concat "File no longer exists: " filen
664 665 666 667 668 669 670 671 672 673 674 675
				    ", write buffer to file? "))
			   (write-file filen))))
		(setq server-existing-buffer t)
		(server-goto-line-column file))
	    (set-buffer (find-file-noselect filen))
	    (server-goto-line-column file)
	    (run-hooks 'server-visit-hook)))
	(unless nowait
	  ;; When the buffer is killed, inform the clients.
	  (add-hook 'kill-buffer-hook 'server-kill-buffer nil t)
	  (push (car client) server-buffer-clients))
	(push (current-buffer) client-record)))
Karoly Lorentey's avatar
Karoly Lorentey committed
676 677 678
    (server-client-set
     client 'buffers
     (nconc (server-client-get client 'buffers) client-record))))
root's avatar
root committed
679

680
(defun server-buffer-done (buffer &optional for-killing)
root's avatar
root committed
681
  "Mark BUFFER as \"done\" for its client(s).
682 683
This buries the buffer, then returns a list of the form (NEXT-BUFFER KILLED).
NEXT-BUFFER is another server buffer, as a suggestion for what to select next,
684 685 686
or nil.  KILLED is t if we killed BUFFER (typically, because it was visiting
a temp file).
FOR-KILLING if non-nil indicates that we are called from `kill-buffer'."
687
  (let ((next-buffer nil)
Karoly Lorentey's avatar
Karoly Lorentey committed
688 689 690
	(killed nil))
    (dolist (client server-clients)
      (let ((buffers (server-client-get client 'buffers)))
691
	(or next-buffer
Karoly Lorentey's avatar
Karoly Lorentey committed
692 693 694 695 696 697 698 699 700 701 702 703 704 705
	    (setq next-buffer (nth 1 (memq buffer buffers))))
	(when buffers			; Ignore bufferless clients.
	  (setq buffers (delq buffer buffers))
	  ;; Delete all dead buffers from CLIENT.
	  (dolist (b buffers)
	    (and (bufferp b)
		 (not (buffer-live-p b))
		 (setq buffers (delq b buffers))))
	  (server-client-set client 'buffers buffers)
	  ;; If client now has no pending buffers,
	  ;; tell it that it is done, and forget it entirely.
	  (unless buffers
	    (server-log "Close" client)
	    (server-delete-client client)))))
706
    (if (and (bufferp buffer) (buffer-name buffer))
707 708 709 710
	;; We may or may not kill this buffer;
	;; if we do, do not call server-buffer-done recursively
	;; from kill-buffer-hook.
	(let ((server-kill-buffer-running t))
711
	  (with-current-buffer buffer
712 713
	    (setq server-buffer-clients nil)
	    (run-hooks 'server-done-hook))
714 715 716 717 718 719
	  ;; Notice whether server-done-hook killed the buffer.
	  (if (null (buffer-name buffer))
	      (setq killed t)
	    ;; Don't bother killing or burying the buffer
	    ;; when we are called from kill-buffer.
	    (unless for-killing
720 721
	      (when (and (not killed)
			 server-kill-new-buffers
722 723
			 (with-current-buffer buffer
			   (not server-existing-buffer)))
724
		(setq killed t)
725
		(bury-buffer buffer)
726 727 728 729 730 731 732
		(kill-buffer buffer))
	      (unless killed
		(if (server-temp-file-p buffer)
		    (progn
		      (kill-buffer buffer)
		      (setq killed t))
		  (bury-buffer buffer)))))))
733
    (list next-buffer killed)))
root's avatar
root committed
734

735
(defun server-temp-file-p (&optional buffer)
root's avatar
root committed
736 737 738 739 740 741 742 743 744 745
  "Return non-nil if BUFFER contains a file considered temporary.
These are files whose names suggest they are repeatedly
reused to pass information to another program.

The variable `server-temp-file-regexp' controls which filenames
are considered temporary."
  (and (buffer-file-name buffer)
       (string-match server-temp-file-regexp (buffer-file-name buffer))))

(defun server-done ()
Christopher Zaborsky's avatar
Christopher Zaborsky committed
746
  "Offer to save current buffer, mark it as \"done\" for clients.
747 748 749 750 751
This kills or buries the buffer, then returns a list
of the form (NEXT-BUFFER KILLED).  NEXT-BUFFER is another server buffer,
as a suggestion for what to select next, or nil.
KILLED is t if we killed BUFFER, which happens if it was created
specifically for the clients and did not exist before their request for it."
752 753 754 755 756 757 758 759 760 761 762 763
  (when server-buffer-clients
    (if (server-temp-file-p)
	;; For a temp file, save, and do make a non-numeric backup
	;; (unless make-backup-files is nil).
	(let ((version-control nil)
	      (buffer-backed-up nil))
	  (save-buffer))
      (if (and (buffer-modified-p)
	       buffer-file-name
	       (y-or-n-p (concat "Save file " buffer-file-name "? ")))
	  (save-buffer)))
    (server-buffer-done (current-buffer))))
764

Richard M. Stallman's avatar
Richard M. Stallman committed
765 766 767 768
;; Ask before killing a server buffer.
;; It was suggested to release its client instead,
;; but I think that is dangerous--the client would proceed
;; using whatever is on disk in that file. -- rms.
769
(defun server-kill-buffer-query-function ()
Karoly Lorentey's avatar
Karoly Lorentey committed
770
  "Ask before killing a server buffer."
771
  (or (not server-buffer-clients)
772 773
      (let ((res t))
	(dolist (proc server-buffer-clients res)
Karoly Lorentey's avatar
Karoly Lorentey committed
774 775 776
	  (let ((client (server-client proc)))
	    (when (and client (eq (process-status proc) 'open))
	      (setq res nil)))))
777 778 779 780
      (yes-or-no-p (format "Buffer `%s' still has clients; kill it? "
			   (buffer-name (current-buffer))))))

(defun server-kill-emacs-query-function ()
Karoly Lorentey's avatar
Karoly Lorentey committed
781 782 783 784 785 786 787 788
  "Ask before exiting Emacs it has are live clients."
  (or (not server-clients)
      (let (live-client)
	(dolist (client server-clients live-client)
	  (if (memq t (mapcar 'buffer-live-p (server-client-get
					      client 'buffers)))
	      (setq live-client t))))
      (yes-or-no-p "This Emacs session has clients; exit anyway? ")))
789

790
(defvar server-kill-buffer-running nil
791
  "Non-nil while `server-kill-buffer' or `server-buffer-done' is running.")
792

793
(defun server-kill-buffer ()
794 795 796
  ;; Prevent infinite recursion if user has made server-done-hook
  ;; call kill-buffer.
  (or server-kill-buffer-running
797 798 799 800
      (and server-buffer-clients
	   (let ((server-kill-buffer-running t))
	     (when server-process
	       (server-buffer-done (current-buffer) t))))))
root's avatar
root committed
801 802 803 804

(defun server-edit (&optional arg)
  "Switch to next server editing buffer; say \"Done\" for current buffer.
If a server buffer is current, it is marked \"done\" and optionally saved.
805
The buffer is also killed if it did not exist before the clients asked for it.
root's avatar
root committed
806 807 808
When all of a client's buffers are marked as \"done\", the client is notified.

Temporary files such as MH <draft> files are always saved and backed up,
809 810 811
no questions asked.  (The variable `make-backup-files', if nil, still
inhibits a backup; you can set it locally in a particular buffer to
prevent a backup for it.)  The variable `server-temp-file-regexp' controls
root's avatar
root committed
812 813
which filenames are considered temporary.

814
If invoked with a prefix argument, or if there is no server process running,
root's avatar
root committed
815 816 817 818 819 820
starts server process and that is all.  Invoked by \\[server-edit]."
  (interactive "P")
  (if (or arg
	  (not server-process)
	  (memq (process-status server-process) '(signal exit)))
      (server-start nil)
821
    (apply 'server-switch-buffer (server-done))))
root's avatar
root committed
822

823
(defun server-switch-buffer (&optional next-buffer killed-one)
root's avatar
root committed
824 825
  "Switch to another buffer, preferably one that has a client.
Arg NEXT-BUFFER is a suggestion; if it is a live buffer, use it."
826 827 828 829
  ;; KILLED-ONE is t in a recursive call
  ;; if we have already killed one temp-file server buffer.
  ;; This means we should avoid the final "switch to some other buffer"
  ;; since we've already effectively done that.
830
  (if (null next-buffer)
Karoly Lorentey's avatar
Karoly Lorentey committed
831 832 833 834 835 836 837 838 839 840 841
      (progn
	(let ((rest server-clients))
	  (while (and rest (not next-buffer))
	    (let ((client (car rest)))
	      ;; Only look at frameless clients.
	      (when (not (server-client-get client 'frame))
		(setq next-buffer (car (server-client-get client 'buffers))))
	      (setq rest (cdr rest)))))
	(and next-buffer (server-switch-buffer next-buffer killed-one))
	(unless (or next-buffer killed-one (window-dedicated-p (selected-window)))
	  ;; (switch-to-buffer (other-buffer))
842
	  (message "No server buffers remain to edit")))
Karoly Lorentey's avatar
Karoly Lorentey committed
843
    (if (not (buffer-live-p next-buffer))
844
	;; If NEXT-BUFFER is a dead buffer, remove the server records for it
root's avatar
root committed
845
	;; and try the next surviving server buffer.
846 847
	(apply 'server-switch-buffer (server-buffer-done next-buffer))
      ;; OK, we know next-buffer is live, let's display and select it.
848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881
      (if (functionp server-window)
	  (funcall server-window next-buffer)
	(let ((win (get-buffer-window next-buffer 0)))
	  (if (and win (not server-window))
	      ;; The buffer is already displayed: just reuse the window.
	      (let ((frame (window-frame win)))
		(if (eq (frame-visible-p frame) 'icon)
		    (raise-frame frame))
		(select-window win)
		(set-buffer next-buffer))
	    ;; Otherwise, let's find an appropriate window.
	    (cond ((and (windowp server-window)
			(window-live-p server-window))
		   (select-window server-window))
		  ((framep server-window)
		   (if (not (frame-live-p server-window))
		       (setq server-window (make-frame)))
		   (select-window (frame-selected-window server-window))))
	    (if (window-minibuffer-p (selected-window))
		(select-window (next-window nil 'nomini 0)))
	    ;; Move to a non-dedicated window, if we have one.
	    (when (window-dedicated-p (selected-window))
	      (select-window
	       (get-window-with-predicate
		(lambda (w)
		  (and (not (window-dedicated-p w))
		       (equal (frame-parameter (window-frame w) 'display)
			      (frame-parameter (selected-frame) 'display))))
		'nomini 'visible (selected-window))))
	    (condition-case nil
		(switch-to-buffer next-buffer)
	      ;; After all the above, we might still have ended up with
	      ;; a minibuffer/dedicated-window (if there's no other).
	      (error (pop-to-buffer next-buffer)))))))))
root's avatar
root committed
882 883

(global-set-key "\C-x#" 'server-edit)
884

885 886
;;;###autoload
(defun server-getenv (variable &optional frame)
887 888 889 890 891 892 893 894 895 896
  "Get the value of VARIABLE in the client environment of frame FRAME.
VARIABLE should be a string.  Value is nil if VARIABLE is undefined in
the environment.  Otherwise, value is a string.

If FRAME is an emacsclient frame, then the variable is looked up
in the environment of the emacsclient process; otherwise the
function consults the environment of the Emacs process.

If FRAME is nil or missing, then the selected frame is used."
  (when (not frame) (setq frame (selected-frame)))
897 898
  (let ((client (frame-parameter frame 'client)) env)
    (if (null client)
899
	(getenv variable)
900
      (setq env (server-client-get client 'environment))
901 902
      (if (null env)
	  (getenv variable)
903
	(cdr (assoc variable env))))))
904

905
(defun server-unload-hook ()
Dave Love's avatar
Dave Love committed
906
  (server-start t)
Karoly Lorentey's avatar
Karoly Lorentey committed
907 908 909
  (remove-hook 'delete-tty-after-functions 'server-handle-delete-tty)
  (remove-hook 'suspend-tty-functions 'server-handle-suspend-tty)
  (remove-hook 'delete-frame-functions 'server-handle-delete-frame)
910 911 912
  (remove-hook 'kill-buffer-query-functions 'server-kill-buffer-query-function)
  (remove-hook 'kill-emacs-query-functions 'server-kill-emacs-query-function)
  (remove-hook 'kill-buffer-hook 'server-kill-buffer))
Roland McGrath's avatar
Roland McGrath committed
913 914

(provide 'server)
Eric S. Raymond's avatar
Eric S. Raymond committed
915

Miles Bader's avatar
Miles Bader committed
916
;;; arch-tag: 1f7ecb42-f00a-49f8-906d-61995d84c8d6
Eric S. Raymond's avatar
Eric S. Raymond committed
917
;;; server.el ends here