Commit | Line | Data |
---|---|---|
c88ab9ce ER |
1 | ;;; server.el --- Lisp code for GNU Emacs running as server process. |
2 | ||
630cc463 | 3 | ;; Author: William Sommerfeld <wesommer@athena.mit.edu> |
e5167999 | 4 | ;; Last-Modified: 05 Dec 1991 |
630cc463 | 5 | |
9ae0f972 | 6 | ;; Changes by peck@sun.com and by rms. |
7 | ||
630cc463 ER |
8 | ;; Copyright (C) 1986, 1987 Free Software Foundation, Inc. |
9 | ||
9ae0f972 | 10 | ;; This file is part of GNU Emacs. |
11 | ||
12 | ;; GNU Emacs is free software; you can redistribute it and/or modify | |
13 | ;; it under the terms of the GNU General Public License as published by | |
e5167999 | 14 | ;; the Free Software Foundation; either version 2, or (at your option) |
9ae0f972 | 15 | ;; any later version. |
16 | ||
17 | ;; GNU Emacs is distributed in the hope that it will be useful, | |
18 | ;; but WITHOUT ANY WARRANTY; without even the implied warranty of | |
19 | ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
20 | ;; GNU General Public License for more details. | |
21 | ||
22 | ;; You should have received a copy of the GNU General Public License | |
23 | ;; along with GNU Emacs; see the file COPYING. If not, write to | |
24 | ;; the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. | |
25 | ||
630cc463 | 26 | ;;; Commentary: |
9ae0f972 | 27 | |
28 | ;;; This Lisp code is run in Emacs when it is to operate as | |
29 | ;;; a server for other processes. | |
30 | ||
31 | ;;; Load this library and do M-x server-edit to enable Emacs as a server. | |
87855006 | 32 | ;;; Emacs runs the program ../arch-lib/emacsserver as a subprocess |
9ae0f972 | 33 | ;;; for communication with clients. If there are no client buffers to edit, |
34 | ;;; server-edit acts like (switch-to-buffer (other-buffer)) | |
35 | ||
36 | ;;; When some other program runs "the editor" to edit a file, | |
87855006 | 37 | ;;; "the editor" can be the Emacs client program ../lib-src/emacsclient. |
9ae0f972 | 38 | ;;; This program transmits the file names to Emacs through |
39 | ;;; the server subprocess, and Emacs visits them and lets you edit them. | |
40 | ||
41 | ;;; Note that any number of clients may dispatch files to emacs to be edited. | |
42 | ||
43 | ;;; When you finish editing a Server buffer, again call server-edit | |
44 | ;;; to mark that buffer as done for the client and switch to the next | |
45 | ;;; Server buffer. When all the buffers for a client have been edited | |
46 | ;;; and exited with server-edit, the client "editor" will return | |
47 | ;;; to the program that invoked it. | |
48 | ||
49 | ;;; Your editing commands and Emacs's display output go to and from | |
50 | ;;; the terminal in the usual way. Thus, server operation is possible | |
51 | ;;; only when Emacs can talk to the terminal at the time you invoke | |
52 | ;;; the client. This is possible in four cases: | |
53 | ||
54 | ;;; 1. On a window system, where Emacs runs in one window and the | |
55 | ;;; program that wants to use "the editor" runs in another. | |
56 | ||
57 | ;;; 2. On a multi-terminal system, where Emacs runs on one terminal and the | |
58 | ;;; program that wants to use "the editor" runs on another. | |
59 | ||
60 | ;;; 3. When the program that wants to use "the editor" is running | |
61 | ;;; as a subprocess of Emacs. | |
62 | ||
63 | ;;; 4. On a system with job control, when Emacs is suspended, the program | |
64 | ;;; that wants to use "the editor" will stop and display | |
65 | ;;; "Waiting for Emacs...". It can then be suspended, and Emacs can be | |
66 | ;;; brought into the foreground for editing. When done editing, Emacs is | |
67 | ;;; suspended again, and the client program is brought into the foreground. | |
68 | ||
69 | ;;; The buffer local variable "server-buffer-clients" lists | |
70 | ;;; the clients who are waiting for this buffer to be edited. | |
71 | ;;; The global variable "server-clients" lists all the waiting clients, | |
72 | ;;; and which files are yet to be edited for each. | |
630cc463 ER |
73 | |
74 | ;;; Code: | |
9ae0f972 | 75 | \f |
76 | (defvar server-program "emacsserver" | |
77 | "*The program to use as the edit server") | |
78 | ||
79 | (defvar server-visit-hook nil | |
80 | "*List of hooks to call when switching to a buffer for the Emacs server.") | |
81 | ||
82 | (defvar server-process nil | |
83 | "the current server process") | |
84 | ||
b53d289e RS |
85 | (defvar server-previous-string "") |
86 | ||
9ae0f972 | 87 | (defvar server-clients nil |
88 | "List of current server clients. | |
89 | Each element is (CLIENTID FILES...) where CLIENTID is a string | |
90 | that can be given to the server process to identify a client. | |
91 | When a buffer is marked as \"done\", it is removed from this list.") | |
92 | ||
93 | (defvar server-buffer-clients nil | |
94 | "List of clientids for clients requesting editing of current buffer.") | |
95 | ;; Changing major modes should not erase this local. | |
96 | (put 'server-buffer-clients 'permanent-local t) | |
97 | ||
98 | (defvar server-temp-file-regexp "^/tmp/Re\\|/draft$" | |
99 | "*Regexp which should match filenames of temporary files | |
100 | which are deleted and reused after each edit | |
101 | by the programs that invoke the emacs server.") | |
102 | ||
103 | (make-variable-buffer-local 'server-buffer-clients) | |
74c9690c | 104 | (put 'server-buffer-clients 'permanent-local t) |
9ae0f972 | 105 | (setq-default server-buffer-clients nil) |
106 | (or (assq 'server-buffer-clients minor-mode-alist) | |
107 | (setq minor-mode-alist (cons '(server-buffer-clients " Server") minor-mode-alist))) | |
108 | ||
109 | ;; If a *server* buffer exists, | |
110 | ;; write STRING to it for logging purposes. | |
111 | (defun server-log (string) | |
112 | (if (get-buffer "*server*") | |
113 | (save-excursion | |
114 | (set-buffer "*server*") | |
115 | (goto-char (point-max)) | |
116 | (insert string) | |
117 | (or (bobp) (newline))))) | |
118 | ||
119 | (defun server-sentinel (proc msg) | |
120 | (cond ((eq (process-status proc) 'exit) | |
121 | (server-log (message "Server subprocess exited"))) | |
122 | ((eq (process-status proc) 'signal) | |
123 | (server-log (message "Server subprocess killed"))))) | |
124 | ||
7229064d | 125 | ;;;###autoload |
9ae0f972 | 126 | (defun server-start (&optional leave-dead) |
127 | "Allow this Emacs process to be a server for client processes. | |
128 | This starts a server communications subprocess through which | |
129 | client \"editors\" can send your editing commands to this Emacs job. | |
130 | To use the server, set up the program `etc/emacsclient' in the | |
131 | Emacs distribution as your standard \"editor\". | |
132 | ||
133 | Prefix arg means just kill any existing server communications subprocess." | |
134 | (interactive "P") | |
135 | ;; kill it dead! | |
136 | (if server-process | |
137 | (progn | |
138 | (set-process-sentinel server-process nil) | |
139 | (condition-case () (delete-process server-process) (error nil)))) | |
140 | (condition-case () (delete-file "~/.emacs_server") (error nil)) | |
141 | ;; If we already had a server, clear out associated status. | |
142 | (while server-clients | |
143 | (let ((buffer (nth 1 (car server-clients)))) | |
144 | (server-buffer-done buffer))) | |
145 | (if leave-dead | |
146 | nil | |
147 | (if server-process | |
148 | (server-log (message "Restarting server"))) | |
149 | (setq server-process (start-process "server" nil server-program)) | |
150 | (set-process-sentinel server-process 'server-sentinel) | |
151 | (set-process-filter server-process 'server-process-filter) | |
152 | (process-kill-without-query server-process))) | |
153 | \f | |
154 | ;Process a request from the server to edit some files. | |
155 | ;Format of STRING is "Client: CLIENTID PATH PATH PATH... \n" | |
156 | (defun server-process-filter (proc string) | |
157 | (server-log string) | |
b53d289e RS |
158 | (setq string (concat server-previous-string string)) |
159 | (if (not (and (eq ?\n (aref string (1- (length string)))) | |
160 | (eq 0 (string-match "Client: " string)))) | |
161 | ;; If input is not complete, save it for later. | |
162 | (setq server-previous-string string) | |
163 | ;; If it is complete, process it now, and discard what was saved. | |
9ae0f972 | 164 | (setq string (substring string (match-end 0))) |
b53d289e | 165 | (setq server-previous-string "") |
9ae0f972 | 166 | (let ((client (list (substring string 0 (string-match " " string)))) |
167 | (files nil) | |
168 | (lineno 1)) | |
169 | (setq string (substring string (match-end 0))) | |
170 | (while (string-match "[^ ]+ " string) | |
171 | (let ((arg | |
172 | (substring string (match-beginning 0) (1- (match-end 0))))) | |
173 | (setq string (substring string (match-end 0))) | |
174 | (if (string-match "\\`\\+[0-9]+\\'" arg) | |
175 | (setq lineno (read (substring arg 1))) | |
176 | (setq files | |
177 | (cons (list arg lineno) | |
178 | files)) | |
179 | (setq lineno 1)))) | |
180 | (server-visit-files files client) | |
181 | ;; CLIENT is now a list (CLIENTNUM BUFFERS...) | |
182 | (setq server-clients (cons client server-clients)) | |
183 | (switch-to-buffer (nth 1 client)) | |
184 | (message (substitute-command-keys | |
185 | "When done with a buffer, type \\[server-edit]."))))) | |
186 | ||
187 | (defun server-visit-files (files client) | |
188 | "Finds FILES and returns the list CLIENT with the buffers nconc'd. | |
189 | FILES is an alist whose elements are (FILENAME LINENUMBER)." | |
190 | (let (client-record) | |
191 | (while files | |
192 | (save-excursion | |
193 | ;; If there is an existing buffer modified or the file is modified, | |
194 | ;; revert it. | |
195 | ;; If there is an existing buffer with deleted file, offer to write it. | |
196 | (let* ((filen (car (car files))) | |
197 | (obuf (get-file-buffer filen))) | |
198 | (if (and obuf (set-buffer obuf)) | |
199 | (if (file-exists-p filen) | |
200 | (if (or (not (verify-visited-file-modtime obuf)) | |
201 | (buffer-modified-p obuf)) | |
202 | (revert-buffer t nil)) | |
203 | (if (y-or-n-p | |
204 | (concat "File no longer exists: " | |
205 | filen | |
206 | ", write buffer to file? ")) | |
207 | (write-file filen))) | |
208 | (set-buffer (find-file-noselect filen)) | |
209 | (run-hooks 'server-visit-hook))) | |
210 | (goto-line (nth 1 (car files))) | |
211 | (setq server-buffer-clients (cons (car client) server-buffer-clients)) | |
212 | (setq client-record (cons (current-buffer) client-record))) | |
213 | (setq files (cdr files))) | |
214 | (nconc client client-record))) | |
215 | \f | |
216 | (defun server-buffer-done (buffer) | |
217 | "Mark BUFFER as \"done\" for its client(s). | |
218 | Buries the buffer, and returns another server buffer | |
219 | as a suggestion for what to select next." | |
220 | (let ((running (eq (process-status server-process) 'run)) | |
221 | (next-buffer nil) | |
222 | (old-clients server-clients)) | |
223 | (while old-clients | |
224 | (let ((client (car old-clients))) | |
225 | (or next-buffer | |
226 | (setq next-buffer (nth 1 (memq buffer client)))) | |
227 | (delq buffer client) | |
228 | ;; If client now has no pending buffers, | |
229 | ;; tell it that it is done, and forget it entirely. | |
230 | (if (cdr client) nil | |
231 | (if running | |
232 | (progn | |
233 | (send-string server-process | |
234 | (format "Close: %s Done\n" (car client))) | |
235 | (server-log (format "Close: %s Done\n" (car client))))) | |
236 | (setq server-clients (delq client server-clients)))) | |
237 | (setq old-clients (cdr old-clients))) | |
238 | (if (buffer-name buffer) | |
239 | (save-excursion | |
240 | (set-buffer buffer) | |
241 | (setq server-buffer-clients nil))) | |
242 | (bury-buffer buffer) | |
243 | next-buffer)) | |
244 | ||
245 | (defun server-temp-file-p (buffer) | |
246 | "Return non-nil if BUFFER contains a file considered temporary. | |
247 | These are files whose names suggest they are repeatedly | |
248 | reused to pass information to another program. | |
249 | ||
250 | The variable `server-temp-file-regexp' controls which filenames | |
251 | are considered temporary." | |
252 | (and (buffer-file-name buffer) | |
253 | (string-match server-temp-file-regexp (buffer-file-name buffer)))) | |
254 | ||
255 | (defun server-done () | |
256 | "Offer to save current buffer, mark it as \"done\" for clients, | |
257 | bury it, and return a suggested buffer to select next." | |
258 | (let ((buffer (current-buffer))) | |
259 | (if server-buffer-clients | |
260 | (progn | |
261 | (if (server-temp-file-p buffer) | |
262 | (progn (save-buffer) | |
263 | (write-region (point-min) (point-max) | |
264 | (concat buffer-file-name "~")) | |
265 | (kill-buffer buffer)) | |
266 | (if (and (buffer-modified-p) | |
267 | (y-or-n-p (concat "Save file " buffer-file-name "? "))) | |
268 | (save-buffer buffer))) | |
269 | (server-buffer-done buffer))))) | |
270 | \f | |
271 | (defun server-edit (&optional arg) | |
272 | "Switch to next server editing buffer; say \"Done\" for current buffer. | |
273 | If a server buffer is current, it is marked \"done\" and optionally saved. | |
274 | When all of a client's buffers are marked as \"done\", the client is notified. | |
275 | ||
276 | Temporary files such as MH <draft> files are always saved and backed up, | |
277 | no questions asked. The variable `server-temp-file-regexp' controls | |
278 | which filenames are considered temporary. | |
279 | ||
280 | If invoked with a prefix argument, or if there is no server process running, | |
281 | starts server process and that is all. Invoked by \\[server-edit]." | |
282 | ||
283 | (interactive "P") | |
284 | (if (or arg | |
285 | (not server-process) | |
286 | (memq (process-status server-process) '(signal exit))) | |
287 | (server-start nil) | |
288 | (server-switch-buffer (server-done)))) | |
289 | ||
290 | (defun server-switch-buffer (next-buffer) | |
291 | "Switch to another buffer, preferably one that has a client. | |
292 | Arg NEXT-BUFFER is a suggestion; if it is a live buffer, use it." | |
293 | (if next-buffer | |
294 | (if (and (bufferp next-buffer) | |
295 | (buffer-name next-buffer)) | |
296 | (switch-to-buffer next-buffer) | |
297 | ;; If NEXT-BUFFER is a dead buffer, | |
298 | ;; remove the server records for it | |
299 | ;; and try the next surviving server buffer. | |
300 | (server-switch-buffer | |
301 | (server-buffer-done next-buffer))) | |
302 | (if server-clients | |
303 | (server-switch-buffer (nth 1 (car server-clients))) | |
304 | (switch-to-buffer (other-buffer))))) | |
305 | ||
306 | (global-set-key "\C-x#" 'server-edit) | |
c88ab9ce ER |
307 | |
308 | ;;; server.el ends here |