1;;; server.el --- Lisp code for GNU Emacs running as server process 2 3;; Copyright (C) 1986, 1987, 1992, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 4;; 2001, 2002, 2003, 2004, 2005, 2006, 2007 Free Software Foundation, Inc. 5 6;; Author: William Sommerfeld <wesommer@athena.mit.edu> 7;; Maintainer: FSF 8;; Keywords: processes 9 10;; Changes by peck@sun.com and by rms. 11 12;; This file is part of GNU Emacs. 13 14;; GNU Emacs is free software; you can redistribute it and/or modify 15;; it under the terms of the GNU General Public License as published by 16;; the Free Software Foundation; either version 2, or (at your option) 17;; any later version. 18 19;; GNU Emacs is distributed in the hope that it will be useful, 20;; but WITHOUT ANY WARRANTY; without even the implied warranty of 21;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 22;; GNU General Public License for more details. 23 24;; You should have received a copy of the GNU General Public License 25;; along with GNU Emacs; see the file COPYING. If not, write to the 26;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, 27;; Boston, MA 02110-1301, USA. 28 29;;; Commentary: 30 31;; This Lisp code is run in Emacs when it is to operate as 32;; a server for other processes. 33 34;; Load this library and do M-x server-edit to enable Emacs as a server. 35;; Emacs opens up a socket for communication with clients. If there are no 36;; client buffers to edit, server-edit acts like (switch-to-buffer 37;; (other-buffer)) 38 39;; When some other program runs "the editor" to edit a file, 40;; "the editor" can be the Emacs client program ../lib-src/emacsclient. 41;; This program transmits the file names to Emacs through 42;; the server subprocess, and Emacs visits them and lets you edit them. 43 44;; Note that any number of clients may dispatch files to emacs to be edited. 45 46;; When you finish editing a Server buffer, again call server-edit 47;; to mark that buffer as done for the client and switch to the next 48;; Server buffer. When all the buffers for a client have been edited 49;; and exited with server-edit, the client "editor" will return 50;; to the program that invoked it. 51 52;; Your editing commands and Emacs's display output go to and from 53;; the terminal in the usual way. Thus, server operation is possible 54;; only when Emacs can talk to the terminal at the time you invoke 55;; the client. This is possible in four cases: 56 57;; 1. On a window system, where Emacs runs in one window and the 58;; program that wants to use "the editor" runs in another. 59 60;; 2. On a multi-terminal system, where Emacs runs on one terminal and the 61;; program that wants to use "the editor" runs on another. 62 63;; 3. When the program that wants to use "the editor" is running 64;; as a subprocess of Emacs. 65 66;; 4. On a system with job control, when Emacs is suspended, the program 67;; that wants to use "the editor" will stop and display 68;; "Waiting for Emacs...". It can then be suspended, and Emacs can be 69;; brought into the foreground for editing. When done editing, Emacs is 70;; suspended again, and the client program is brought into the foreground. 71 72;; The buffer local variable "server-buffer-clients" lists 73;; the clients who are waiting for this buffer to be edited. 74;; The global variable "server-clients" lists all the waiting clients, 75;; and which files are yet to be edited for each. 76 77;;; Code: 78 79(eval-when-compile (require 'cl)) 80 81(defgroup server nil 82 "Emacs running as a server process." 83 :group 'external) 84 85(defcustom server-use-tcp nil 86 "If non-nil, use TCP sockets instead of local sockets." 87 :set #'(lambda (sym val) 88 (unless (featurep 'make-network-process '(:family local)) 89 (setq val t) 90 (unless load-in-progress 91 (message "Local sockets unsupported, using TCP sockets"))) 92 (when val (random t)) 93 (set-default sym val)) 94 :group 'server 95 :type 'boolean 96 :version "22.1") 97 98(defcustom server-host nil 99 "The name or IP address to use as host address of the server process. 100If set, the server accepts remote connections; otherwise it is local." 101 :group 'server 102 :type '(choice 103 (string :tag "Name or IP address") 104 (const :tag "Local" nil)) 105 :version "22.1") 106(put 'server-host 'risky-local-variable t) 107 108(defcustom server-auth-dir "~/.emacs.d/server/" 109 "Directory for server authentication files." 110 :group 'server 111 :type 'directory 112 :version "22.1") 113(put 'server-auth-dir 'risky-local-variable t) 114 115(defcustom server-raise-frame t 116 "If non-nil, raise frame when switching to a buffer." 117 :group 'server 118 :type 'boolean 119 :version "22.1") 120 121(defcustom server-visit-hook nil 122 "Hook run when visiting a file for the Emacs server." 123 :group 'server 124 :type 'hook) 125 126(defcustom server-switch-hook nil 127 "Hook run when switching to a buffer for the Emacs server." 128 :group 'server 129 :type 'hook) 130 131(defcustom server-done-hook nil 132 "Hook run when done editing a buffer for the Emacs server." 133 :group 'server 134 :type 'hook) 135 136(defvar server-process nil 137 "The current server process.") 138 139(defvar server-clients nil 140 "List of current server clients. 141Each element is (CLIENTID BUFFERS...) where CLIENTID is a string 142that can be given to the server process to identify a client. 143When a buffer is marked as \"done\", it is removed from this list.") 144 145(defvar server-buffer-clients nil 146 "List of client ids for clients requesting editing of current buffer.") 147(make-variable-buffer-local 'server-buffer-clients) 148;; Changing major modes should not erase this local. 149(put 'server-buffer-clients 'permanent-local t) 150 151(defcustom server-window nil 152 "Specification of the window to use for selecting Emacs server buffers. 153If nil, use the selected window. 154If it is a function, it should take one argument (a buffer) and 155display and select it. A common value is `pop-to-buffer'. 156If it is a window, use that. 157If it is a frame, use the frame's selected window. 158 159It is not meaningful to set this to a specific frame or window with Custom. 160Only programs can do so." 161 :group 'server 162 :version "22.1" 163 :type '(choice (const :tag "Use selected window" 164 :match (lambda (widget value) 165 (not (functionp value))) 166 nil) 167 (function-item :tag "Use pop-to-buffer" pop-to-buffer) 168 (function :tag "Other function"))) 169 170(defcustom server-temp-file-regexp "^/tmp/Re\\|/draft$" 171 "Regexp matching names of temporary files. 172These are deleted and reused after each edit by the programs that 173invoke the Emacs server." 174 :group 'server 175 :type 'regexp) 176 177(defcustom server-kill-new-buffers t 178 "Whether to kill buffers when done with them. 179If non-nil, kill a buffer unless it already existed before editing 180it with Emacs server. If nil, kill only buffers as specified by 181`server-temp-file-regexp'. 182Please note that only buffers are killed that still have a client, 183i.e. buffers visited which \"emacsclient --no-wait\" are never killed in 184this way." 185 :group 'server 186 :type 'boolean 187 :version "21.1") 188 189(or (assq 'server-buffer-clients minor-mode-alist) 190 (push '(server-buffer-clients " Server") minor-mode-alist)) 191 192(defvar server-existing-buffer nil 193 "Non-nil means the buffer existed before the server was asked to visit it. 194This means that the server should not kill the buffer when you say you 195are done with it in the server.") 196(make-variable-buffer-local 'server-existing-buffer) 197 198(defvar server-name "server") 199 200(defvar server-socket-dir 201 (format "/tmp/emacs%d" (user-uid))) 202 203(defun server-log (string &optional client) 204 "If a *server* buffer exists, write STRING to it for logging purposes." 205 (when (get-buffer "*server*") 206 (with-current-buffer "*server*" 207 (goto-char (point-max)) 208 (insert (current-time-string) 209 (if client (format " %s:" client) " ") 210 string) 211 (or (bolp) (newline))))) 212 213(defun server-sentinel (proc msg) 214 (let ((client (assq proc server-clients))) 215 ;; Remove PROC from the list of clients. 216 (when client 217 (setq server-clients (delq client server-clients)) 218 (dolist (buf (cdr client)) 219 (with-current-buffer buf 220 ;; Remove PROC from the clients of each buffer. 221 (setq server-buffer-clients (delq proc server-buffer-clients)) 222 ;; Kill the buffer if necessary. 223 (when (and (null server-buffer-clients) 224 (or (and server-kill-new-buffers 225 (not server-existing-buffer)) 226 (server-temp-file-p))) 227 (kill-buffer (current-buffer))))))) 228 ;; If this is a new client process, set the query-on-exit flag to nil 229 ;; for this process (it isn't inherited from the server process). 230 (when (and (eq (process-status proc) 'open) 231 (process-query-on-exit-flag proc)) 232 (set-process-query-on-exit-flag proc nil)) 233 ;; Delete the associated connection file, if applicable. 234 ;; This is actually problematic: the file may have been overwritten by 235 ;; another Emacs server in the mean time, so it's not ours any more. 236 ;; (and (process-contact proc :server) 237 ;; (eq (process-status proc) 'closed) 238 ;; (ignore-errors (delete-file (process-get proc :server-file)))) 239 (server-log (format "Status changed to %s" (process-status proc)) proc)) 240 241(defun server-select-display (display) 242 ;; If the current frame is on `display' we're all set. 243 (unless (equal (frame-parameter (selected-frame) 'display) display) 244 ;; Otherwise, look for an existing frame there and select it. 245 (dolist (frame (frame-list)) 246 (when (equal (frame-parameter frame 'display) display) 247 (select-frame frame))) 248 ;; If there's no frame on that display yet, create and select one. 249 (unless (equal (frame-parameter (selected-frame) 'display) display) 250 (let* ((buffer (generate-new-buffer " *server-dummy*")) 251 (frame (make-frame-on-display 252 display 253 ;; Make it display (and remember) some dummy buffer, so 254 ;; we can detect later if the frame is in use or not. 255 `((server-dummmy-buffer . ,buffer) 256 ;; This frame may be deleted later (see 257 ;; server-unselect-display) so we want it to be as 258 ;; unobtrusive as possible. 259 (visibility . nil))))) 260 (select-frame frame) 261 (set-window-buffer (selected-window) buffer))))) 262 263(defun server-unselect-display (frame) 264 ;; If the temporary frame is in use (displays something real), make it 265 ;; visible. If not (which can happen if the user's customizations call 266 ;; pop-to-buffer etc.), delete it to avoid preserving the connection after 267 ;; the last real frame is deleted. 268 (if (and (eq (frame-first-window frame) 269 (next-window (frame-first-window frame) 'nomini)) 270 (eq (window-buffer (frame-first-window frame)) 271 (frame-parameter frame 'server-dummy-buffer))) 272 ;; The temp frame still only shows one buffer, and that is the 273 ;; internal temp buffer. 274 (delete-frame frame) 275 (set-frame-parameter frame 'visibility t)) 276 (kill-buffer (frame-parameter frame 'server-dummy-buffer)) 277 (set-frame-parameter frame 'server-dummy-buffer nil)) 278 279(defun server-unquote-arg (arg) 280 (replace-regexp-in-string 281 "&." (lambda (s) 282 (case (aref s 1) 283 (?& "&") 284 (?- "-") 285 (?n "\n") 286 (t " "))) 287 arg t t)) 288 289(defun server-ensure-safe-dir (dir) 290 "Make sure DIR is a directory with no race-condition issues. 291Creates the directory if necessary and makes sure: 292- there's no symlink involved 293- it's owned by us 294- it's not readable/writable by anybody else." 295 (setq dir (directory-file-name dir)) 296 (let ((attrs (file-attributes dir))) 297 (unless attrs 298 (letf (((default-file-modes) ?\700)) (make-directory dir t)) 299 (setq attrs (file-attributes dir))) 300 ;; Check that it's safe for use. 301 (unless (and (eq t (car attrs)) (eql (nth 2 attrs) (user-uid)) 302 (or (eq system-type 'windows-nt) 303 (zerop (logand ?\077 (file-modes dir))))) 304 (error "The directory %s is unsafe" dir)))) 305 306;;;###autoload 307(defun server-start (&optional leave-dead) 308 "Allow this Emacs process to be a server for client processes. 309This starts a server communications subprocess through which 310client \"editors\" can send your editing commands to this Emacs job. 311To use the server, set up the program `emacsclient' in the 312Emacs distribution as your standard \"editor\". 313 314Optional argument LEAVE-DEAD (interactively, a prefix arg) means just 315kill any existing server communications subprocess." 316 (interactive "P") 317 (when server-process 318 ;; kill it dead! 319 (ignore-errors (delete-process server-process))) 320 ;; If this Emacs already had a server, clear out associated status. 321 (while server-clients 322 (let ((buffer (nth 1 (car server-clients)))) 323 (server-buffer-done buffer))) 324 ;; Now any previous server is properly stopped. 325 (unless leave-dead 326 (let* ((server-dir (if server-use-tcp server-auth-dir server-socket-dir)) 327 (server-file (expand-file-name server-name server-dir))) 328 ;; Make sure there is a safe directory in which to place the socket. 329 (server-ensure-safe-dir server-dir) 330 ;; Remove any leftover socket or authentication file. 331 (ignore-errors (delete-file server-file)) 332 (when server-process 333 (server-log (message "Restarting server"))) 334 (letf (((default-file-modes) ?\700)) 335 (setq server-process 336 (apply #'make-network-process 337 :name server-name 338 :server t 339 :noquery t 340 :sentinel 'server-sentinel 341 :filter 'server-process-filter 342 ;; We must receive file names without being decoded. 343 ;; Those are decoded by server-process-filter according 344 ;; to file-name-coding-system. 345 :coding 'raw-text 346 ;; The rest of the args depends on the kind of socket used. 347 (if server-use-tcp 348 (list :family nil 349 :service t 350 :host (or server-host 'local) 351 :plist '(:authenticated nil)) 352 (list :family 'local 353 :service server-file 354 :plist '(:authenticated t))))) 355 (unless server-process (error "Could not start server process")) 356 (when server-use-tcp 357 (let ((auth-key 358 (loop 359 ;; The auth key is a 64-byte string of random chars in the 360 ;; range `!'..`~'. 361 for i below 64 362 collect (+ 33 (random 94)) into auth 363 finally return (concat auth)))) 364 (process-put server-process :auth-key auth-key) 365 (with-temp-file server-file 366 (set-buffer-multibyte nil) 367 (setq buffer-file-coding-system 'no-conversion) 368 (insert (format-network-address 369 (process-contact server-process :local)) 370 " " (int-to-string (emacs-pid)) 371 "\n" auth-key)))))))) 372 373;;;###autoload 374(define-minor-mode server-mode 375 "Toggle Server mode. 376With ARG, turn Server mode on if ARG is positive, off otherwise. 377Server mode runs a process that accepts commands from the 378`emacsclient' program. See `server-start' and Info node `Emacs server'." 379 :global t 380 :group 'server 381 :version "22.1" 382 ;; Fixme: Should this check for an existing server socket and do 383 ;; nothing if there is one (for multiple Emacs sessions)? 384 (server-start (not server-mode))) 385 386(defun* server-process-filter (proc string) 387 "Process a request from the server to edit some files. 388PROC is the server process. Format of STRING is \"PATH PATH PATH... \\n\"." 389 ;; First things first: let's check the authentication 390 (unless (process-get proc :authenticated) 391 (if (and (string-match "-auth \\(.*?\\)\n" string) 392 (equal (match-string 1 string) (process-get proc :auth-key))) 393 (progn 394 (setq string (substring string (match-end 0))) 395 (process-put proc :authenticated t) 396 (server-log "Authentication successful" proc)) 397 (server-log "Authentication failed" proc) 398 (process-send-string proc "Authentication failed") 399 (delete-process proc) 400 ;; We return immediately 401 (return-from server-process-filter))) 402 (server-log string proc) 403 (let ((prev (process-get proc :previous-string))) 404 (when prev 405 (setq string (concat prev string)) 406 (process-put proc :previous-string nil))) 407 (when (> (recursion-depth) 0) 408 ;; We're inside a minibuffer already, so if the emacs-client is trying 409 ;; to open a frame on a new display, we might end up with an unusable 410 ;; frame because input from that display will be blocked (until exiting 411 ;; the minibuffer). Better exit this minibuffer right away. 412 ;; Similarly with recursive-edits such as the splash screen. 413 (process-put proc :previous-string string) 414 (run-with-timer 0 nil (lexical-let ((proc proc)) 415 (lambda () (server-process-filter proc "")))) 416 (top-level)) 417 (condition-case nil 418 ;; If we're running isearch, we must abort it to allow Emacs to 419 ;; display the buffer and switch to it. 420 (mapc #'(lambda (buffer) 421 (with-current-buffer buffer 422 (when (bound-and-true-p isearch-mode) 423 (isearch-cancel)))) 424 (buffer-list)) 425 ;; Signaled by isearch-cancel 426 (quit (message nil))) 427 ;; If the input is multiple lines, 428 ;; process each line individually. 429 (while (string-match "\n" string) 430 (let ((request (substring string 0 (match-beginning 0))) 431 (coding-system (and default-enable-multibyte-characters 432 (or file-name-coding-system 433 default-file-name-coding-system))) 434 client nowait eval 435 (files nil) 436 (lineno 1) 437 (tmp-frame nil) ;; Sometimes used to embody the selected display. 438 (columnno 0)) 439 ;; Remove this line from STRING. 440 (setq string (substring string (match-end 0))) 441 (setq client (cons proc nil)) 442 (while (string-match "[^ ]* " request) 443 (let ((arg (substring request (match-beginning 0) (1- (match-end 0))))) 444 (setq request (substring request (match-end 0))) 445 (cond 446 ((equal "-nowait" arg) (setq nowait t)) 447 ((equal "-eval" arg) (setq eval t)) 448 ((and (equal "-display" arg) (string-match "\\([^ ]*\\) " request)) 449 (let ((display (server-unquote-arg (match-string 1 request)))) 450 (setq request (substring request (match-end 0))) 451 (condition-case err 452 (setq tmp-frame (server-select-display display)) 453 (error (process-send-string proc (nth 1 err)) 454 (setq request ""))))) 455 ;; ARG is a line number option. 456 ((string-match "\\`\\+[0-9]+\\'" arg) 457 (setq lineno (string-to-number (substring arg 1)))) 458 ;; ARG is line number:column option. 459 ((string-match "\\`+\\([0-9]+\\):\\([0-9]+\\)\\'" arg) 460 (setq lineno (string-to-number (match-string 1 arg)) 461 columnno (string-to-number (match-string 2 arg)))) 462 (t 463 ;; Undo the quoting that emacsclient does 464 ;; for certain special characters. 465 (setq arg (server-unquote-arg arg)) 466 ;; Now decode the file name if necessary. 467 (when coding-system 468 (setq arg (decode-coding-string arg coding-system))) 469 (if eval 470 (let* (errorp 471 (v (condition-case errobj 472 (eval (car (read-from-string arg))) 473 (error (setq errorp t) errobj)))) 474 (when v 475 (with-temp-buffer 476 (let ((standard-output (current-buffer))) 477 (when errorp (princ "error: ")) 478 (pp v) 479 (ignore-errors 480 (process-send-region proc (point-min) (point-max))) 481 )))) 482 ;; ARG is a file name. 483 ;; Collapse multiple slashes to single slashes. 484 (setq arg (command-line-normalize-file-name arg)) 485 (push (list arg lineno columnno) files)) 486 (setq lineno 1) 487 (setq columnno 0))))) 488 (when files 489 (run-hooks 'pre-command-hook) 490 (server-visit-files files client nowait) 491 (run-hooks 'post-command-hook)) 492 ;; CLIENT is now a list (CLIENTNUM BUFFERS...) 493 (if (null (cdr client)) 494 ;; This client is empty; get rid of it immediately. 495 (progn 496 (delete-process proc) 497 (server-log "Close empty client" proc)) 498 ;; We visited some buffer for this client. 499 (or nowait (push client server-clients)) 500 (unless (or isearch-mode (minibufferp)) 501 (server-switch-buffer (nth 1 client)) 502 (run-hooks 'server-switch-hook) 503 (unless nowait 504 (message "%s" (substitute-command-keys 505 "When done with a buffer, type \\[server-edit]"))))) 506 (when (frame-live-p tmp-frame) 507 ;; Delete tmp-frame or make it visible depending on whether it's 508 ;; been used or not. 509 (server-unselect-display tmp-frame)))) 510 ;; Save for later any partial line that remains. 511 (when (> (length string) 0) 512 (process-put proc :previous-string string))) 513 514(defun server-goto-line-column (file-line-col) 515 (goto-line (nth 1 file-line-col)) 516 (let ((column-number (nth 2 file-line-col))) 517 (when (> column-number 0) 518 (move-to-column (1- column-number))))) 519 520(defun server-visit-files (files client &optional nowait) 521 "Find FILES and return the list CLIENT with the buffers nconc'd. 522FILES is an alist whose elements are (FILENAME LINENUMBER COLUMNNUMBER). 523NOWAIT non-nil means this client is not waiting for the results, 524so don't mark these buffers specially, just visit them normally." 525 ;; Bind last-nonmenu-event to force use of keyboard, not mouse, for queries. 526 (let ((last-nonmenu-event t) client-record) 527 ;; Restore the current buffer afterward, but not using save-excursion, 528 ;; because we don't want to save point in this buffer 529 ;; if it happens to be one of those specified by the server. 530 (save-current-buffer 531 (dolist (file files) 532 ;; If there is an existing buffer modified or the file is 533 ;; modified, revert it. If there is an existing buffer with 534 ;; deleted file, offer to write it. 535 (let* ((minibuffer-auto-raise (or server-raise-frame 536 minibuffer-auto-raise)) 537 (filen (car file)) 538 (obuf (get-file-buffer filen))) 539 (add-to-history 'file-name-history filen) 540 (if (and obuf (set-buffer obuf)) 541 (progn 542 (cond ((file-exists-p filen) 543 (when (not (verify-visited-file-modtime obuf)) 544 (revert-buffer t nil))) 545 (t 546 (when (y-or-n-p 547 (concat "File no longer exists: " 548 filen 549 ", write buffer to file? ")) 550 (write-file filen)))) 551 (setq server-existing-buffer t) 552 (server-goto-line-column file)) 553 (set-buffer (find-file-noselect filen)) 554 (server-goto-line-column file) 555 (run-hooks 'server-visit-hook))) 556 (unless nowait 557 ;; When the buffer is killed, inform the clients. 558 (add-hook 'kill-buffer-hook 'server-kill-buffer nil t) 559 (push (car client) server-buffer-clients)) 560 (push (current-buffer) client-record))) 561 (nconc client client-record))) 562 563(defun server-buffer-done (buffer &optional for-killing) 564 "Mark BUFFER as \"done\" for its client(s). 565This buries the buffer, then returns a list of the form (NEXT-BUFFER KILLED). 566NEXT-BUFFER is another server buffer, as a suggestion for what to select next, 567or nil. KILLED is t if we killed BUFFER (typically, because it was visiting 568a temp file). 569FOR-KILLING if non-nil indicates that we are called from `kill-buffer'." 570 (let ((next-buffer nil) 571 (killed nil) 572 (old-clients server-clients)) 573 (while old-clients 574 (let ((client (car old-clients))) 575 (or next-buffer 576 (setq next-buffer (nth 1 (memq buffer client)))) 577 (delq buffer client) 578 ;; Delete all dead buffers from CLIENT. 579 (let ((tail client)) 580 (while tail 581 (and (bufferp (car tail)) 582 (null (buffer-name (car tail))) 583 (delq (car tail) client)) 584 (setq tail (cdr tail)))) 585 ;; If client now has no pending buffers, 586 ;; tell it that it is done, and forget it entirely. 587 (unless (cdr client) 588 (delete-process (car client)) 589 (server-log "Close" (car client)) 590 (setq server-clients (delq client server-clients)))) 591 (setq old-clients (cdr old-clients))) 592 (when (and (bufferp buffer) (buffer-name buffer)) 593 ;; We may or may not kill this buffer; 594 ;; if we do, do not call server-buffer-done recursively 595 ;; from kill-buffer-hook. 596 (let ((server-kill-buffer-running t)) 597 (with-current-buffer buffer 598 (setq server-buffer-clients nil) 599 (run-hooks 'server-done-hook)) 600 ;; Notice whether server-done-hook killed the buffer. 601 (if (null (buffer-name buffer)) 602 (setq killed t) 603 ;; Don't bother killing or burying the buffer 604 ;; when we are called from kill-buffer. 605 (unless for-killing 606 (when (and (not killed) 607 server-kill-new-buffers 608 (with-current-buffer buffer 609 (not server-existing-buffer))) 610 (setq killed t) 611 (bury-buffer buffer) 612 (kill-buffer buffer)) 613 (unless killed 614 (if (server-temp-file-p buffer) 615 (progn 616 (kill-buffer buffer) 617 (setq killed t)) 618 (bury-buffer buffer))))))) 619 (list next-buffer killed))) 620 621(defun server-temp-file-p (&optional buffer) 622 "Return non-nil if BUFFER contains a file considered temporary. 623These are files whose names suggest they are repeatedly 624reused to pass information to another program. 625 626The variable `server-temp-file-regexp' controls which filenames 627are considered temporary." 628 (and (buffer-file-name buffer) 629 (string-match server-temp-file-regexp (buffer-file-name buffer)))) 630 631(defun server-done () 632 "Offer to save current buffer, mark it as \"done\" for clients. 633This kills or buries the buffer, then returns a list 634of the form (NEXT-BUFFER KILLED). NEXT-BUFFER is another server buffer, 635as a suggestion for what to select next, or nil. 636KILLED is t if we killed BUFFER, which happens if it was created 637specifically for the clients and did not exist before their request for it." 638 (when server-buffer-clients 639 (if (server-temp-file-p) 640 ;; For a temp file, save, and do make a non-numeric backup 641 ;; (unless make-backup-files is nil). 642 (let ((version-control nil) 643 (buffer-backed-up nil)) 644 (save-buffer)) 645 (when (and (buffer-modified-p) 646 buffer-file-name 647 (y-or-n-p (concat "Save file " buffer-file-name "? "))) 648 (save-buffer))) 649 (server-buffer-done (current-buffer)))) 650 651;; Ask before killing a server buffer. 652;; It was suggested to release its client instead, 653;; but I think that is dangerous--the client would proceed 654;; using whatever is on disk in that file. -- rms. 655(defun server-kill-buffer-query-function () 656 (or (not server-buffer-clients) 657 (yes-or-no-p (format "Buffer `%s' still has clients; kill it? " 658 (buffer-name (current-buffer)))))) 659 660(add-hook 'kill-buffer-query-functions 661 'server-kill-buffer-query-function) 662 663(defun server-kill-emacs-query-function () 664 (let (live-client 665 (tail server-clients)) 666 ;; See if any clients have any buffers that are still alive. 667 (while tail 668 (when (memq t (mapcar 'stringp (mapcar 'buffer-name (cdr (car tail))))) 669 (setq live-client t)) 670 (setq tail (cdr tail))) 671 (or (not live-client) 672 (yes-or-no-p "Server buffers still have clients; exit anyway? ")))) 673 674(add-hook 'kill-emacs-query-functions 'server-kill-emacs-query-function) 675 676(defvar server-kill-buffer-running nil 677 "Non-nil while `server-kill-buffer' or `server-buffer-done' is running.") 678 679(defun server-kill-buffer () 680 ;; Prevent infinite recursion if user has made server-done-hook 681 ;; call kill-buffer. 682 (or server-kill-buffer-running 683 (and server-buffer-clients 684 (let ((server-kill-buffer-running t)) 685 (when server-process 686 (server-buffer-done (current-buffer) t)))))) 687 688(defun server-edit (&optional arg) 689 "Switch to next server editing buffer; say \"Done\" for current buffer. 690If a server buffer is current, it is marked \"done\" and optionally saved. 691The buffer is also killed if it did not exist before the clients asked for it. 692When all of a client's buffers are marked as \"done\", the client is notified. 693 694Temporary files such as MH <draft> files are always saved and backed up, 695no questions asked. (The variable `make-backup-files', if nil, still 696inhibits a backup; you can set it locally in a particular buffer to 697prevent a backup for it.) The variable `server-temp-file-regexp' controls 698which filenames are considered temporary. 699 700If invoked with a prefix argument, or if there is no server process running, 701starts server process and that is all. Invoked by \\[server-edit]." 702 (interactive "P") 703 (cond 704 ((or arg 705 (not server-process) 706 (memq (process-status server-process) '(signal exit))) 707 (server-mode 1)) 708 (server-clients (apply 'server-switch-buffer (server-done))) 709 (t (message "No server editing buffers exist")))) 710 711(defun server-switch-buffer (&optional next-buffer killed-one) 712 "Switch to another buffer, preferably one that has a client. 713Arg NEXT-BUFFER is a suggestion; if it is a live buffer, use it." 714 ;; KILLED-ONE is t in a recursive call 715 ;; if we have already killed one temp-file server buffer. 716 ;; This means we should avoid the final "switch to some other buffer" 717 ;; since we've already effectively done that. 718 (if (null next-buffer) 719 (if server-clients 720 (server-switch-buffer (nth 1 (car server-clients)) killed-one) 721 (unless (or killed-one (window-dedicated-p (selected-window))) 722 (switch-to-buffer (other-buffer)) 723 (message "No server buffers remain to edit"))) 724 (if (not (buffer-name next-buffer)) 725 ;; If NEXT-BUFFER is a dead buffer, remove the server records for it 726 ;; and try the next surviving server buffer. 727 (apply 'server-switch-buffer (server-buffer-done next-buffer)) 728 ;; OK, we know next-buffer is live, let's display and select it. 729 (if (functionp server-window) 730 (funcall server-window next-buffer) 731 (let ((win (get-buffer-window next-buffer 0))) 732 (if (and win (not server-window)) 733 ;; The buffer is already displayed: just reuse the window. 734 (progn 735 (select-window win) 736 (set-buffer next-buffer)) 737 ;; Otherwise, let's find an appropriate window. 738 (cond ((and (windowp server-window) 739 (window-live-p server-window)) 740 (select-window server-window)) 741 ((framep server-window) 742 (unless (frame-live-p server-window) 743 (setq server-window (make-frame))) 744 (select-window (frame-selected-window server-window)))) 745 (when (window-minibuffer-p (selected-window)) 746 (select-window (next-window nil 'nomini 0))) 747 ;; Move to a non-dedicated window, if we have one. 748 (when (window-dedicated-p (selected-window)) 749 (select-window 750 (get-window-with-predicate 751 (lambda (w) 752 (and (not (window-dedicated-p w)) 753 (equal (frame-parameter (window-frame w) 'display) 754 (frame-parameter (selected-frame) 'display)))) 755 'nomini 'visible (selected-window)))) 756 (condition-case nil 757 (switch-to-buffer next-buffer) 758 ;; After all the above, we might still have ended up with 759 ;; a minibuffer/dedicated-window (if there's no other). 760 (error (pop-to-buffer next-buffer))))))) 761 (when server-raise-frame 762 (select-frame-set-input-focus (window-frame (selected-window)))))) 763 764(define-key ctl-x-map "#" 'server-edit) 765 766(defun server-unload-hook () 767 (server-mode -1) 768 (remove-hook 'kill-buffer-query-functions 'server-kill-buffer-query-function) 769 (remove-hook 'kill-emacs-query-functions 'server-kill-emacs-query-function) 770 (remove-hook 'kill-buffer-hook 'server-kill-buffer)) 771 772(add-hook 'kill-emacs-hook (lambda () (server-mode -1))) ;Cleanup upon exit. 773(add-hook 'server-unload-hook 'server-unload-hook) 774 775(provide 'server) 776 777;; arch-tag: 1f7ecb42-f00a-49f8-906d-61995d84c8d6 778;;; server.el ends here 779