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3a993e3d MA |
1 | ;;; dbus.el --- Elisp bindings for D-Bus. |
2 | ||
d665fff0 | 3 | ;; Copyright (C) 2007, 2008, 2009 Free Software Foundation, Inc. |
3a993e3d MA |
4 | |
5 | ;; Author: Michael Albinus <michael.albinus@gmx.de> | |
6 | ;; Keywords: comm, hardware | |
7 | ||
8 | ;; This file is part of GNU Emacs. | |
9 | ||
874a927a | 10 | ;; GNU Emacs is free software: you can redistribute it and/or modify |
3a993e3d | 11 | ;; it under the terms of the GNU General Public License as published by |
874a927a GM |
12 | ;; the Free Software Foundation, either version 3 of the License, or |
13 | ;; (at your option) any later version. | |
3a993e3d MA |
14 | |
15 | ;; GNU Emacs is distributed in the hope that it will be useful, | |
16 | ;; but WITHOUT ANY WARRANTY; without even the implied warranty of | |
17 | ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
18 | ;; GNU General Public License for more details. | |
19 | ||
20 | ;; You should have received a copy of the GNU General Public License | |
874a927a | 21 | ;; along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>. |
3a993e3d MA |
22 | |
23 | ;;; Commentary: | |
24 | ||
25 | ;; This package provides language bindings for the D-Bus API. D-Bus | |
26 | ;; is a message bus system, a simple way for applications to talk to | |
27 | ;; one another. See <http://dbus.freedesktop.org/> for details. | |
28 | ||
29 | ;; Low-level language bindings are implemented in src/dbusbind.c. | |
30 | ||
31 | ;;; Code: | |
32 | ||
7bb7efbd | 33 | ;; D-Bus support in the Emacs core can be disabled with configuration |
6981d00a MA |
34 | ;; option "--without-dbus". Declare used subroutines and variables. |
35 | (declare-function dbus-call-method "dbusbind.c") | |
52a39a64 | 36 | (declare-function dbus-call-method-asynchronously "dbusbind.c") |
ba6f7d86 | 37 | (declare-function dbus-init-bus "dbusbind.c") |
5e895c06 MA |
38 | (declare-function dbus-method-return-internal "dbusbind.c") |
39 | (declare-function dbus-method-error-internal "dbusbind.c") | |
6981d00a MA |
40 | (declare-function dbus-register-signal "dbusbind.c") |
41 | (defvar dbus-debug) | |
42 | (defvar dbus-registered-functions-table) | |
43 | ||
ba6f7d86 MA |
44 | ;; Initialize :system and :session buses. This adds their file |
45 | ;; descriptors to input_wait_mask, in order to detect incoming | |
46 | ;; messages immediately. | |
47 | ;; We must avoid to call the function twice for a bus, because the | |
48 | ;; DBusWatch will be removed then. | |
49 | (when (and (featurep 'dbusbind) (not (featurep 'dbus))) | |
50 | (dbus-init-bus :system) | |
51 | (dbus-init-bus :session)) | |
52 | ||
6981d00a MA |
53 | ;; Pacify byte compiler. |
54 | (eval-when-compile | |
55 | (require 'cl)) | |
7bb7efbd | 56 | |
3a993e3d MA |
57 | (require 'xml) |
58 | ||
59 | (defconst dbus-service-dbus "org.freedesktop.DBus" | |
60 | "The bus name used to talk to the bus itself.") | |
61 | ||
62 | (defconst dbus-path-dbus "/org/freedesktop/DBus" | |
63 | "The object path used to talk to the bus itself.") | |
64 | ||
65 | (defconst dbus-interface-dbus "org.freedesktop.DBus" | |
66 | "The interface exported by the object with `dbus-service-dbus' and `dbus-path-dbus'.") | |
67 | ||
4ba11bcb MA |
68 | (defconst dbus-interface-peer (concat dbus-interface-dbus ".Peer") |
69 | "The interface for peer objects.") | |
70 | ||
71 | (defconst dbus-interface-introspectable | |
72 | (concat dbus-interface-dbus ".Introspectable") | |
3a993e3d MA |
73 | "The interface supported by introspectable objects.") |
74 | ||
f636d3ca MA |
75 | (defconst dbus-interface-properties (concat dbus-interface-dbus ".Properties") |
76 | "The interface for property objects.") | |
77 | ||
65b7cb2c MA |
78 | (defconst dbus-service-emacs "org.gnu.Emacs" |
79 | "The well known service name of Emacs.") | |
80 | ||
81 | (defconst dbus-path-emacs "/org/gnu/Emacs" | |
82 | "The object path head used by Emacs.") | |
83 | ||
98c38bfc MA |
84 | (defconst dbus-message-type-invalid 0 |
85 | "This value is never a valid message type.") | |
86 | ||
87 | (defconst dbus-message-type-method-call 1 | |
88 | "Message type of a method call message.") | |
89 | ||
90 | (defconst dbus-message-type-method-return 2 | |
91 | "Message type of a method return message.") | |
92 | ||
93 | (defconst dbus-message-type-error 3 | |
94 | "Message type of an error reply message.") | |
95 | ||
96 | (defconst dbus-message-type-signal 4 | |
97 | "Message type of a signal message.") | |
98 | ||
246a286b MA |
99 | (defmacro dbus-ignore-errors (&rest body) |
100 | "Execute BODY; signal D-Bus error when `dbus-debug' is non-nil. | |
101 | Otherwise, return result of last form in BODY, or all other errors." | |
102 | `(condition-case err | |
103 | (progn ,@body) | |
104 | (dbus-error (when dbus-debug (signal (car err) (cdr err)))))) | |
105 | ||
106 | (put 'dbus-ignore-errors 'lisp-indent-function 0) | |
98c38bfc | 107 | (put 'dbus-ignore-errors 'edebug-form-spec '(form body)) |
246a286b MA |
108 | (font-lock-add-keywords 'emacs-lisp-mode '("\\<dbus-ignore-errors\\>")) |
109 | ||
e12c189f MA |
110 | (defvar dbus-event-error-hooks nil |
111 | "Functions to be called when a D-Bus error happens in the event handler. | |
f213fc09 | 112 | Every function must accept two arguments, the event and the error variable |
e12c189f MA |
113 | catched in `condition-case' by `dbus-error'.") |
114 | ||
5363d8ea MA |
115 | \f |
116 | ;;; Hash table of registered functions. | |
117 | ||
79945ac1 MA |
118 | ;; We create it here. So we have a simple test in dbusbind.c, whether |
119 | ;; the Lisp code has been loaded. | |
120 | (setq dbus-registered-functions-table (make-hash-table :test 'equal)) | |
5363d8ea | 121 | |
98c38bfc MA |
122 | (defvar dbus-return-values-table (make-hash-table :test 'equal) |
123 | "Hash table for temporary storing arguments of reply messages. | |
124 | A key in this hash table is a list (BUS SERIAL). BUS is either the | |
125 | symbol `:system' or the symbol `:session'. SERIAL is the serial number | |
126 | of the reply message. See `dbus-call-method-non-blocking-handler' and | |
127 | `dbus-call-method-non-blocking'.") | |
128 | ||
ef6ce14c | 129 | (defun dbus-list-hash-table () |
e49d337b | 130 | "Returns all registered member registrations to D-Bus. |
ef6ce14c MA |
131 | The return value is a list, with elements of kind (KEY . VALUE). |
132 | See `dbus-registered-functions-table' for a description of the | |
133 | hash table." | |
134 | (let (result) | |
135 | (maphash | |
136 | '(lambda (key value) (add-to-list 'result (cons key value) 'append)) | |
137 | dbus-registered-functions-table) | |
138 | result)) | |
139 | ||
246a286b MA |
140 | (defun dbus-unregister-object (object) |
141 | "Unregister OBJECT from D-Bus. | |
142 | OBJECT must be the result of a preceding `dbus-register-method' | |
f636d3ca MA |
143 | or `dbus-register-signal' call. It returns `t' if OBJECT has |
144 | been unregistered, `nil' otherwise." | |
246a286b MA |
145 | ;; Check parameter. |
146 | (unless (and (consp object) (not (null (car object))) (consp (cdr object))) | |
147 | (signal 'wrong-type-argument (list 'D-Bus object))) | |
148 | ||
149 | ;; Find the corresponding entry in the hash table. | |
150 | (let* ((key (car object)) | |
151 | (value (gethash key dbus-registered-functions-table))) | |
152 | ;; Loop over the registered functions. | |
153 | (while (consp value) | |
154 | ;; (car value) has the structure (UNAME SERVICE PATH HANDLER). | |
155 | ;; (cdr object) has the structure ((SERVICE PATH HANDLER) ...). | |
156 | (if (not (equal (cdr (car value)) (car (cdr object)))) | |
157 | (setq value (cdr value)) | |
158 | ;; Compute new hash value. If it is empty, remove it from | |
159 | ;; hash table. | |
160 | (unless | |
161 | (puthash | |
162 | key | |
163 | (delete (car value) (gethash key dbus-registered-functions-table)) | |
164 | dbus-registered-functions-table) | |
165 | (remhash key dbus-registered-functions-table)) | |
166 | (setq value t))) | |
167 | value)) | |
168 | ||
98c38bfc MA |
169 | (defun dbus-call-method-non-blocking-handler (&rest args) |
170 | "Handler for reply messages of asynchronous D-Bus message calls. | |
171 | It calls the function stored in `dbus-registered-functions-table'. | |
172 | The result will be made available in `dbus-return-values-table'." | |
173 | (puthash (list (dbus-event-bus-name last-input-event) | |
174 | (dbus-event-serial-number last-input-event)) | |
175 | (if (= (length args) 1) (car args) args) | |
176 | dbus-return-values-table)) | |
177 | ||
178 | (defun dbus-call-method-non-blocking | |
179 | (bus service path interface method &rest args) | |
180 | "Call METHOD on the D-Bus BUS, but don't block the event queue. | |
181 | This is necessary for communicating to registered D-Bus methods, | |
182 | which are running in the same Emacs process. | |
183 | ||
184 | The arguments are the same as in `dbus-call-method'. | |
185 | ||
186 | usage: (dbus-call-method-non-blocking | |
187 | BUS SERVICE PATH INTERFACE METHOD | |
188 | &optional :timeout TIMEOUT &rest ARGS)" | |
189 | ||
190 | (let ((key | |
191 | (apply | |
192 | 'dbus-call-method-asynchronously | |
193 | bus service path interface method | |
194 | 'dbus-call-method-non-blocking-handler args))) | |
195 | ;; Wait until `dbus-call-method-non-blocking-handler' has put the | |
196 | ;; result into `dbus-return-values-table'. | |
3dec5c36 | 197 | (while (eq (gethash key dbus-return-values-table :ignore) :ignore) |
98c38bfc MA |
198 | (read-event nil nil 0.1)) |
199 | ||
200 | ;; Cleanup `dbus-return-values-table'. Return the result. | |
201 | (prog1 | |
202 | (gethash key dbus-return-values-table nil) | |
203 | (remhash key dbus-return-values-table)))) | |
204 | ||
0e0c4247 | 205 | (defun dbus-name-owner-changed-handler (&rest args) |
e49d337b | 206 | "Reapplies all member registrations to D-Bus. |
ef6ce14c MA |
207 | This handler is applied when a \"NameOwnerChanged\" signal has |
208 | arrived. SERVICE is the object name for which the name owner has | |
209 | been changed. OLD-OWNER is the previous owner of SERVICE, or the | |
210 | empty string if SERVICE was not owned yet. NEW-OWNER is the new | |
0e0c4247 MA |
211 | owner of SERVICE, or the empty string if SERVICE looses any name owner. |
212 | ||
213 | usage: (dbus-name-owner-changed-handler service old-owner new-owner)" | |
ef6ce14c | 214 | (save-match-data |
0e0c4247 MA |
215 | ;; Check the arguments. We should silently ignore it when they |
216 | ;; are wrong. | |
217 | (if (and (= (length args) 3) | |
218 | (stringp (car args)) | |
219 | (stringp (cadr args)) | |
220 | (stringp (caddr args))) | |
221 | (let ((service (car args)) | |
222 | (old-owner (cadr args)) | |
223 | (new-owner (caddr args))) | |
224 | ;; Check whether SERVICE is a known name. | |
225 | (when (not (string-match "^:" service)) | |
226 | (maphash | |
227 | '(lambda (key value) | |
228 | (dolist (elt value) | |
e49d337b | 229 | ;; key has the structure (BUS INTERFACE MEMBER). |
0e0c4247 MA |
230 | ;; elt has the structure (UNAME SERVICE PATH HANDLER). |
231 | (when (string-equal old-owner (car elt)) | |
232 | ;; Remove old key, and add new entry with changed name. | |
7d1112ae | 233 | (dbus-unregister-object (list key (cdr elt))) |
0e0c4247 MA |
234 | ;; Maybe we could arrange the lists a little bit better |
235 | ;; that we don't need to extract every single element? | |
236 | (dbus-register-signal | |
237 | ;; BUS SERVICE PATH | |
238 | (nth 0 key) (nth 1 elt) (nth 2 elt) | |
e49d337b | 239 | ;; INTERFACE MEMBER HANDLER |
0e0c4247 MA |
240 | (nth 1 key) (nth 2 key) (nth 3 elt))))) |
241 | (copy-hash-table dbus-registered-functions-table)))) | |
242 | ;; The error is reported only in debug mode. | |
243 | (when dbus-debug | |
244 | (signal | |
245 | 'dbus-error | |
246 | (cons | |
247 | (format "Wrong arguments of %s.NameOwnerChanged" dbus-interface-dbus) | |
248 | args)))))) | |
ef6ce14c MA |
249 | |
250 | ;; Register the handler. | |
98c38bfc | 251 | (when nil ;ignore-errors |
246a286b MA |
252 | (dbus-register-signal |
253 | :system dbus-service-dbus dbus-path-dbus dbus-interface-dbus | |
254 | "NameOwnerChanged" 'dbus-name-owner-changed-handler) | |
255 | (dbus-register-signal | |
256 | :session dbus-service-dbus dbus-path-dbus dbus-interface-dbus | |
257 | "NameOwnerChanged" 'dbus-name-owner-changed-handler)) | |
ef6ce14c | 258 | |
5363d8ea | 259 | \f |
82697a45 MA |
260 | ;;; D-Bus type conversion. |
261 | ||
262 | (defun dbus-string-to-byte-array (string) | |
263 | "Transforms STRING to list (:array :byte c1 :byte c2 ...). | |
264 | STRING shall be UTF8 coded." | |
d665fff0 MA |
265 | (if (zerop (length string)) |
266 | '(:array :signature "y") | |
267 | (let (result) | |
268 | (dolist (elt (string-to-list string) (append '(:array) result)) | |
269 | (setq result (append result (list :byte elt))))))) | |
82697a45 MA |
270 | |
271 | (defun dbus-byte-array-to-string (byte-array) | |
272 | "Transforms BYTE-ARRAY into UTF8 coded string. | |
273 | BYTE-ARRAY must be a list of structure (c1 c2 ...)." | |
274 | (apply 'string byte-array)) | |
275 | ||
276 | (defun dbus-escape-as-identifier (string) | |
277 | "Escape an arbitrary STRING so it follows the rules for a C identifier. | |
278 | The escaped string can be used as object path component, interface element | |
279 | component, bus name component or member name in D-Bus. | |
280 | ||
281 | The escaping consists of replacing all non-alphanumerics, and the | |
282 | first character if it's a digit, with an underscore and two | |
283 | lower-case hex digits: | |
284 | ||
285 | \"0123abc_xyz\\x01\\xff\" -> \"_30123abc_5fxyz_01_ff\" | |
286 | ||
287 | i.e. similar to URI encoding, but with \"_\" taking the role of \"%\", | |
288 | and a smaller allowed set. As a special case, \"\" is escaped to | |
289 | \"_\". | |
290 | ||
291 | Returns the escaped string. Algorithm taken from | |
292 | telepathy-glib's `tp-escape-as-identifier'." | |
293 | (if (zerop (length string)) | |
294 | "_" | |
295 | (replace-regexp-in-string | |
296 | "^[0-9]\\|[^A-Za-z0-9]" | |
297 | (lambda (x) (format "_%2x" (aref x 0))) | |
298 | string))) | |
299 | ||
300 | (defun dbus-unescape-from-identifier (string) | |
301 | "Retrieve the original string from the encoded STRING. | |
302 | STRING must have been coded with `dbus-escape-as-identifier'" | |
303 | (if (string-equal string "_") | |
304 | "" | |
305 | (replace-regexp-in-string | |
306 | "_.." | |
307 | (lambda (x) (format "%c" (string-to-number (substring x 1) 16))) | |
308 | string))) | |
309 | ||
310 | \f | |
5363d8ea MA |
311 | ;;; D-Bus events. |
312 | ||
3a993e3d MA |
313 | (defun dbus-check-event (event) |
314 | "Checks whether EVENT is a well formed D-Bus event. | |
315 | EVENT is a list which starts with symbol `dbus-event': | |
316 | ||
98c38bfc | 317 | (dbus-event BUS TYPE SERIAL SERVICE PATH INTERFACE MEMBER HANDLER &rest ARGS) |
3a993e3d | 318 | |
e49d337b | 319 | BUS identifies the D-Bus the message is coming from. It is |
98c38bfc MA |
320 | either the symbol `:system' or the symbol `:session'. TYPE is |
321 | the D-Bus message type which has caused the event, SERIAL is the | |
322 | serial number of the received D-Bus message. SERVICE and PATH | |
323 | are the unique name and the object path of the D-Bus object | |
324 | emitting the message. INTERFACE and MEMBER denote the message | |
325 | which has been sent. HANDLER is the function which has been | |
326 | registered for this message. ARGS are the arguments passed to | |
327 | HANDLER, when it is called during event handling in | |
328 | `dbus-handle-event'. | |
3a993e3d MA |
329 | |
330 | This function raises a `dbus-error' signal in case the event is | |
331 | not well formed." | |
332 | (when dbus-debug (message "DBus-Event %s" event)) | |
333 | (unless (and (listp event) | |
334 | (eq (car event) 'dbus-event) | |
5363d8ea | 335 | ;; Bus symbol. |
ef6ce14c | 336 | (symbolp (nth 1 event)) |
98c38bfc MA |
337 | ;; Type. |
338 | (and (natnump (nth 2 event)) | |
339 | (< dbus-message-type-invalid (nth 2 event))) | |
e49d337b | 340 | ;; Serial. |
98c38bfc | 341 | (natnump (nth 3 event)) |
5363d8ea | 342 | ;; Service. |
98c38bfc | 343 | (or (= dbus-message-type-method-return (nth 2 event)) |
ba0b66b0 | 344 | (= dbus-message-type-error (nth 2 event)) |
98c38bfc | 345 | (stringp (nth 4 event))) |
e49d337b | 346 | ;; Object path. |
98c38bfc | 347 | (or (= dbus-message-type-method-return (nth 2 event)) |
ba0b66b0 | 348 | (= dbus-message-type-error (nth 2 event)) |
98c38bfc | 349 | (stringp (nth 5 event))) |
e49d337b | 350 | ;; Interface. |
98c38bfc | 351 | (or (= dbus-message-type-method-return (nth 2 event)) |
ba0b66b0 | 352 | (= dbus-message-type-error (nth 2 event)) |
98c38bfc | 353 | (stringp (nth 6 event))) |
e49d337b | 354 | ;; Member. |
98c38bfc | 355 | (or (= dbus-message-type-method-return (nth 2 event)) |
ba0b66b0 | 356 | (= dbus-message-type-error (nth 2 event)) |
98c38bfc | 357 | (stringp (nth 7 event))) |
ef6ce14c | 358 | ;; Handler. |
98c38bfc | 359 | (functionp (nth 8 event))) |
3a993e3d MA |
360 | (signal 'dbus-error (list "Not a valid D-Bus event" event)))) |
361 | ||
362 | ;;;###autoload | |
363 | (defun dbus-handle-event (event) | |
364 | "Handle events from the D-Bus. | |
5363d8ea | 365 | EVENT is a D-Bus event, see `dbus-check-event'. HANDLER, being |
98c38bfc MA |
366 | part of the event, is called with arguments ARGS. |
367 | If the HANDLER returns an `dbus-error', it is propagated as return message." | |
3a993e3d | 368 | (interactive "e") |
98c38bfc MA |
369 | (condition-case err |
370 | (let (result) | |
ba0b66b0 | 371 | ;; We ignore not well-formed events. |
98c38bfc | 372 | (dbus-check-event event) |
ba0b66b0 MA |
373 | ;; Error messages must be propagated. |
374 | (when (= dbus-message-type-error (nth 2 event)) | |
375 | (signal 'dbus-error (nthcdr 9 event))) | |
376 | ;; Apply the handler. | |
98c38bfc MA |
377 | (setq result (apply (nth 8 event) (nthcdr 9 event))) |
378 | ;; Return a message when it is a message call. | |
379 | (when (= dbus-message-type-method-call (nth 2 event)) | |
380 | (dbus-ignore-errors | |
3dec5c36 MA |
381 | (if (eq result :ignore) |
382 | (dbus-method-return-internal | |
383 | (nth 1 event) (nth 3 event) (nth 4 event)) | |
384 | (apply 'dbus-method-return-internal | |
385 | (nth 1 event) (nth 3 event) (nth 4 event) | |
386 | (if (consp result) result (list result))))))) | |
98c38bfc MA |
387 | ;; Error handling. |
388 | (dbus-error | |
389 | ;; Return an error message when it is a message call. | |
390 | (when (= dbus-message-type-method-call (nth 2 event)) | |
391 | (dbus-ignore-errors | |
392 | (dbus-method-error-internal | |
393 | (nth 1 event) (nth 3 event) (nth 4 event) (cadr err)))) | |
ba0b66b0 | 394 | ;; Propagate D-Bus error messages. |
f213fc09 | 395 | (run-hook-with-args 'dbus-event-error-hooks event err) |
ba0b66b0 MA |
396 | (when (or dbus-debug (= dbus-message-type-error (nth 2 event))) |
397 | (signal (car err) (cdr err)))))) | |
3a993e3d MA |
398 | |
399 | (defun dbus-event-bus-name (event) | |
400 | "Return the bus name the event is coming from. | |
401 | The result is either the symbol `:system' or the symbol `:session'. | |
402 | EVENT is a D-Bus event, see `dbus-check-event'. This function | |
403 | raises a `dbus-error' signal in case the event is not well | |
404 | formed." | |
405 | (dbus-check-event event) | |
ef6ce14c | 406 | (nth 1 event)) |
3a993e3d | 407 | |
98c38bfc MA |
408 | (defun dbus-event-message-type (event) |
409 | "Return the message type of the corresponding D-Bus message. | |
410 | The result is a number. EVENT is a D-Bus event, see | |
411 | `dbus-check-event'. This function raises a `dbus-error' signal | |
412 | in case the event is not well formed." | |
413 | (dbus-check-event event) | |
414 | (nth 2 event)) | |
415 | ||
e49d337b MA |
416 | (defun dbus-event-serial-number (event) |
417 | "Return the serial number of the corresponding D-Bus message. | |
98c38bfc MA |
418 | The result is a number. The serial number is needed for |
419 | generating a reply message. EVENT is a D-Bus event, see | |
420 | `dbus-check-event'. This function raises a `dbus-error' signal | |
421 | in case the event is not well formed." | |
e49d337b | 422 | (dbus-check-event event) |
98c38bfc | 423 | (nth 3 event)) |
e49d337b | 424 | |
3a993e3d | 425 | (defun dbus-event-service-name (event) |
5363d8ea | 426 | "Return the name of the D-Bus object the event is coming from. |
3a993e3d MA |
427 | The result is a string. EVENT is a D-Bus event, see `dbus-check-event'. |
428 | This function raises a `dbus-error' signal in case the event is | |
429 | not well formed." | |
430 | (dbus-check-event event) | |
98c38bfc | 431 | (nth 4 event)) |
3a993e3d MA |
432 | |
433 | (defun dbus-event-path-name (event) | |
434 | "Return the object path of the D-Bus object the event is coming from. | |
435 | The result is a string. EVENT is a D-Bus event, see `dbus-check-event'. | |
436 | This function raises a `dbus-error' signal in case the event is | |
437 | not well formed." | |
438 | (dbus-check-event event) | |
98c38bfc | 439 | (nth 5 event)) |
3a993e3d MA |
440 | |
441 | (defun dbus-event-interface-name (event) | |
442 | "Return the interface name of the D-Bus object the event is coming from. | |
443 | The result is a string. EVENT is a D-Bus event, see `dbus-check-event'. | |
444 | This function raises a `dbus-error' signal in case the event is | |
445 | not well formed." | |
446 | (dbus-check-event event) | |
98c38bfc | 447 | (nth 6 event)) |
3a993e3d MA |
448 | |
449 | (defun dbus-event-member-name (event) | |
450 | "Return the member name the event is coming from. | |
451 | It is either a signal name or a method name. The result is is a | |
452 | string. EVENT is a D-Bus event, see `dbus-check-event'. This | |
453 | function raises a `dbus-error' signal in case the event is not | |
454 | well formed." | |
455 | (dbus-check-event event) | |
98c38bfc | 456 | (nth 7 event)) |
5363d8ea MA |
457 | |
458 | \f | |
459 | ;;; D-Bus registered names. | |
3a993e3d MA |
460 | |
461 | (defun dbus-list-activatable-names () | |
462 | "Return the D-Bus service names which can be activated as list. | |
f636d3ca | 463 | The result is a list of strings, which is `nil' when there are no |
3a993e3d | 464 | activatable service names at all." |
246a286b MA |
465 | (dbus-ignore-errors |
466 | (dbus-call-method | |
467 | :system dbus-service-dbus | |
468 | dbus-path-dbus dbus-interface-dbus "ListActivatableNames"))) | |
3a993e3d MA |
469 | |
470 | (defun dbus-list-names (bus) | |
471 | "Return the service names registered at D-Bus BUS. | |
f636d3ca MA |
472 | The result is a list of strings, which is `nil' when there are no |
473 | registered service names at all. Well known names are strings | |
474 | like \"org.freedesktop.DBus\". Names starting with \":\" are | |
475 | unique names for services." | |
246a286b MA |
476 | (dbus-ignore-errors |
477 | (dbus-call-method | |
478 | bus dbus-service-dbus dbus-path-dbus dbus-interface-dbus "ListNames"))) | |
3a993e3d MA |
479 | |
480 | (defun dbus-list-known-names (bus) | |
481 | "Retrieve all services which correspond to a known name in BUS. | |
482 | A service has a known name if it doesn't start with \":\"." | |
483 | (let (result) | |
484 | (dolist (name (dbus-list-names bus) result) | |
485 | (unless (string-equal ":" (substring name 0 1)) | |
486 | (add-to-list 'result name 'append))))) | |
487 | ||
488 | (defun dbus-list-queued-owners (bus service) | |
f636d3ca MA |
489 | "Return the unique names registered at D-Bus BUS and queued for SERVICE. |
490 | The result is a list of strings, or `nil' when there are no | |
491 | queued name owners service names at all." | |
246a286b MA |
492 | (dbus-ignore-errors |
493 | (dbus-call-method | |
494 | bus dbus-service-dbus dbus-path-dbus | |
495 | dbus-interface-dbus "ListQueuedOwners" service))) | |
3a993e3d MA |
496 | |
497 | (defun dbus-get-name-owner (bus service) | |
498 | "Return the name owner of SERVICE registered at D-Bus BUS. | |
f636d3ca | 499 | The result is either a string, or `nil' if there is no name owner." |
246a286b MA |
500 | (dbus-ignore-errors |
501 | (dbus-call-method | |
502 | bus dbus-service-dbus dbus-path-dbus | |
503 | dbus-interface-dbus "GetNameOwner" service))) | |
3a993e3d | 504 | |
4ba11bcb MA |
505 | (defun dbus-ping (bus service) |
506 | "Check whether SERVICE is registered for D-Bus BUS." | |
507 | ;; "Ping" raises a D-Bus error if SERVICE does not exist. | |
508 | ;; Otherwise, it returns silently with `nil'. | |
509 | (condition-case nil | |
510 | (not | |
511 | (dbus-call-method bus service dbus-path-dbus dbus-interface-peer "Ping")) | |
512 | (dbus-error nil))) | |
513 | ||
f636d3ca MA |
514 | \f |
515 | ;;; D-Bus introspection. | |
3a993e3d | 516 | |
f636d3ca MA |
517 | (defun dbus-introspect (bus service path) |
518 | "This function returns all interfaces and sub-nodes of SERVICE, | |
519 | registered at object path PATH at bus BUS. | |
520 | ||
521 | BUS must be either the symbol `:system' or the symbol `:session'. | |
522 | SERVICE must be a known service name, and PATH must be a valid | |
523 | object path. The last two parameters are strings. The result, | |
524 | the introspection data, is a string in XML format." | |
736215fd MA |
525 | ;; We don't want to raise errors. `dbus-call-method-non-blocking' |
526 | ;; is used, because the handler can be registered in our Emacs | |
527 | ;; instance; caller an callee would block each other. | |
246a286b | 528 | (dbus-ignore-errors |
736215fd | 529 | (dbus-call-method-non-blocking |
246a286b | 530 | bus service path dbus-interface-introspectable "Introspect"))) |
3a993e3d | 531 | |
f636d3ca MA |
532 | (defun dbus-introspect-xml (bus service path) |
533 | "Return the introspection data of SERVICE in D-Bus BUS at object path PATH. | |
534 | The data are a parsed list. The root object is a \"node\", | |
535 | representing the object path PATH. The root object can contain | |
536 | \"interface\" and further \"node\" objects." | |
537 | ;; We don't want to raise errors. | |
538 | (xml-node-name | |
539 | (ignore-errors | |
540 | (with-temp-buffer | |
541 | (insert (dbus-introspect bus service path)) | |
542 | (xml-parse-region (point-min) (point-max)))))) | |
543 | ||
544 | (defun dbus-introspect-get-attribute (object attribute) | |
545 | "Return the ATTRIBUTE value of D-Bus introspection OBJECT. | |
546 | ATTRIBUTE must be a string according to the attribute names in | |
547 | the D-Bus specification." | |
548 | (xml-get-attribute-or-nil object (intern attribute))) | |
549 | ||
550 | (defun dbus-introspect-get-node-names (bus service path) | |
551 | "Return all node names of SERVICE in D-Bus BUS at object path PATH. | |
552 | It returns a list of strings. The node names stand for further | |
553 | object paths of the D-Bus service." | |
554 | (let ((object (dbus-introspect-xml bus service path)) | |
555 | result) | |
556 | (dolist (elt (xml-get-children object 'node) result) | |
557 | (add-to-list | |
558 | 'result (dbus-introspect-get-attribute elt "name") 'append)))) | |
559 | ||
560 | (defun dbus-introspect-get-all-nodes (bus service path) | |
561 | "Return all node names of SERVICE in D-Bus BUS at object path PATH. | |
562 | It returns a list of strings, which are further object paths of SERVICE." | |
563 | (let ((result (list path))) | |
564 | (dolist (elt | |
565 | (dbus-introspect-get-node-names bus service path) | |
566 | result) | |
567 | (setq elt (expand-file-name elt path)) | |
568 | (setq result | |
569 | (append result (dbus-introspect-get-all-nodes bus service elt)))))) | |
570 | ||
571 | (defun dbus-introspect-get-interface-names (bus service path) | |
572 | "Return all interface names of SERVICE in D-Bus BUS at object path PATH. | |
573 | It returns a list of strings. | |
574 | ||
575 | There will be always the default interface | |
576 | \"org.freedesktop.DBus.Introspectable\". Another default | |
577 | interface is \"org.freedesktop.DBus.Properties\". If present, | |
578 | \"interface\" objects can also have \"property\" objects as | |
579 | children, beside \"method\" and \"signal\" objects." | |
580 | (let ((object (dbus-introspect-xml bus service path)) | |
581 | result) | |
582 | (dolist (elt (xml-get-children object 'interface) result) | |
583 | (add-to-list | |
584 | 'result (dbus-introspect-get-attribute elt "name") 'append)))) | |
585 | ||
586 | (defun dbus-introspect-get-interface (bus service path interface) | |
587 | "Return the INTERFACE of SERVICE in D-Bus BUS at object path PATH. | |
588 | The return value is an XML object. INTERFACE must be a string, | |
589 | element of the list returned by | |
590 | `dbus-introspect-get-interface-names'. The resulting | |
591 | \"interface\" object can contain \"method\", \"signal\", | |
592 | \"property\" and \"annotation\" children." | |
593 | (let ((elt (xml-get-children | |
594 | (dbus-introspect-xml bus service path) 'interface))) | |
595 | (while (and elt | |
596 | (not (string-equal | |
597 | interface | |
598 | (dbus-introspect-get-attribute (car elt) "name")))) | |
599 | (setq elt (cdr elt))) | |
600 | (car elt))) | |
601 | ||
602 | (defun dbus-introspect-get-method-names (bus service path interface) | |
603 | "Return a list of strings of all method names of INTERFACE. | |
604 | SERVICE is a service of D-Bus BUS at object path PATH." | |
605 | (let ((object (dbus-introspect-get-interface bus service path interface)) | |
606 | result) | |
607 | (dolist (elt (xml-get-children object 'method) result) | |
608 | (add-to-list | |
609 | 'result (dbus-introspect-get-attribute elt "name") 'append)))) | |
610 | ||
611 | (defun dbus-introspect-get-method (bus service path interface method) | |
612 | "Return method METHOD of interface INTERFACE as XML object. | |
613 | It must be located at SERVICE in D-Bus BUS at object path PATH. | |
614 | METHOD must be a string, element of the list returned by | |
615 | `dbus-introspect-get-method-names'. The resulting \"method\" | |
616 | object can contain \"arg\" and \"annotation\" children." | |
617 | (let ((elt (xml-get-children | |
618 | (dbus-introspect-get-interface bus service path interface) | |
619 | 'method))) | |
620 | (while (and elt | |
621 | (not (string-equal | |
622 | method (dbus-introspect-get-attribute (car elt) "name")))) | |
623 | (setq elt (cdr elt))) | |
624 | (car elt))) | |
625 | ||
626 | (defun dbus-introspect-get-signal-names (bus service path interface) | |
627 | "Return a list of strings of all signal names of INTERFACE. | |
628 | SERVICE is a service of D-Bus BUS at object path PATH." | |
629 | (let ((object (dbus-introspect-get-interface bus service path interface)) | |
630 | result) | |
631 | (dolist (elt (xml-get-children object 'signal) result) | |
632 | (add-to-list | |
633 | 'result (dbus-introspect-get-attribute elt "name") 'append)))) | |
634 | ||
635 | (defun dbus-introspect-get-signal (bus service path interface signal) | |
636 | "Return signal SIGNAL of interface INTERFACE as XML object. | |
637 | It must be located at SERVICE in D-Bus BUS at object path PATH. | |
638 | SIGNAL must be a string, element of the list returned by | |
639 | `dbus-introspect-get-signal-names'. The resulting \"signal\" | |
640 | object can contain \"arg\" and \"annotation\" children." | |
641 | (let ((elt (xml-get-children | |
642 | (dbus-introspect-get-interface bus service path interface) | |
643 | 'signal))) | |
644 | (while (and elt | |
645 | (not (string-equal | |
646 | signal (dbus-introspect-get-attribute (car elt) "name")))) | |
647 | (setq elt (cdr elt))) | |
648 | (car elt))) | |
649 | ||
650 | (defun dbus-introspect-get-property-names (bus service path interface) | |
651 | "Return a list of strings of all property names of INTERFACE. | |
652 | SERVICE is a service of D-Bus BUS at object path PATH." | |
653 | (let ((object (dbus-introspect-get-interface bus service path interface)) | |
654 | result) | |
655 | (dolist (elt (xml-get-children object 'property) result) | |
656 | (add-to-list | |
657 | 'result (dbus-introspect-get-attribute elt "name") 'append)))) | |
658 | ||
659 | (defun dbus-introspect-get-property (bus service path interface property) | |
660 | "This function returns PROPERTY of INTERFACE as XML object. | |
661 | It must be located at SERVICE in D-Bus BUS at object path PATH. | |
662 | PROPERTY must be a string, element of the list returned by | |
663 | `dbus-introspect-get-property-names'. The resulting PROPERTY | |
664 | object can contain \"annotation\" children." | |
665 | (let ((elt (xml-get-children | |
666 | (dbus-introspect-get-interface bus service path interface) | |
667 | 'property))) | |
668 | (while (and elt | |
669 | (not (string-equal | |
670 | property | |
671 | (dbus-introspect-get-attribute (car elt) "name")))) | |
672 | (setq elt (cdr elt))) | |
673 | (car elt))) | |
674 | ||
675 | (defun dbus-introspect-get-annotation-names | |
676 | (bus service path interface &optional name) | |
677 | "Return all annotation names as list of strings. | |
678 | If NAME is `nil', the annotations are children of INTERFACE, | |
679 | otherwise NAME must be a \"method\", \"signal\", or \"property\" | |
680 | object, where the annotations belong to." | |
681 | (let ((object | |
682 | (if name | |
683 | (or (dbus-introspect-get-method bus service path interface name) | |
684 | (dbus-introspect-get-signal bus service path interface name) | |
685 | (dbus-introspect-get-property bus service path interface name)) | |
686 | (dbus-introspect-get-interface bus service path interface))) | |
687 | result) | |
688 | (dolist (elt (xml-get-children object 'annotation) result) | |
689 | (add-to-list | |
690 | 'result (dbus-introspect-get-attribute elt "name") 'append)))) | |
691 | ||
692 | (defun dbus-introspect-get-annotation | |
693 | (bus service path interface name annotation) | |
694 | "Return ANNOTATION as XML object. | |
695 | If NAME is `nil', ANNOTATION is a child of INTERFACE, otherwise | |
696 | NAME must be the name of a \"method\", \"signal\", or | |
697 | \"property\" object, where the ANNOTATION belongs to." | |
698 | (let ((elt (xml-get-children | |
699 | (if name | |
700 | (or (dbus-introspect-get-method | |
701 | bus service path interface name) | |
702 | (dbus-introspect-get-signal | |
703 | bus service path interface name) | |
704 | (dbus-introspect-get-property | |
705 | bus service path interface name)) | |
706 | (dbus-introspect-get-interface bus service path interface)) | |
707 | 'annotation))) | |
708 | (while (and elt | |
709 | (not (string-equal | |
710 | annotation | |
711 | (dbus-introspect-get-attribute (car elt) "name")))) | |
712 | (setq elt (cdr elt))) | |
713 | (car elt))) | |
714 | ||
715 | (defun dbus-introspect-get-argument-names (bus service path interface name) | |
716 | "Return a list of all argument names as list of strings. | |
717 | NAME must be a \"method\" or \"signal\" object. | |
718 | ||
719 | Argument names are optional, the function can return `nil' | |
720 | therefore, even if the method or signal has arguments." | |
721 | (let ((object | |
722 | (or (dbus-introspect-get-method bus service path interface name) | |
723 | (dbus-introspect-get-signal bus service path interface name))) | |
724 | result) | |
725 | (dolist (elt (xml-get-children object 'arg) result) | |
726 | (add-to-list | |
727 | 'result (dbus-introspect-get-attribute elt "name") 'append)))) | |
728 | ||
729 | (defun dbus-introspect-get-argument (bus service path interface name arg) | |
730 | "Return argument ARG as XML object. | |
731 | NAME must be a \"method\" or \"signal\" object. ARG must be a | |
732 | string, element of the list returned by `dbus-introspect-get-argument-names'." | |
733 | (let ((elt (xml-get-children | |
734 | (or (dbus-introspect-get-method bus service path interface name) | |
735 | (dbus-introspect-get-signal bus service path interface name)) | |
736 | 'arg))) | |
737 | (while (and elt | |
738 | (not (string-equal | |
739 | arg (dbus-introspect-get-attribute (car elt) "name")))) | |
740 | (setq elt (cdr elt))) | |
741 | (car elt))) | |
742 | ||
743 | (defun dbus-introspect-get-signature | |
744 | (bus service path interface name &optional direction) | |
745 | "Return signature of a `method' or `signal', represented by NAME, as string. | |
746 | If NAME is a `method', DIRECTION can be either \"in\" or \"out\". | |
747 | If DIRECTION is `nil', \"in\" is assumed. | |
748 | ||
749 | If NAME is a `signal', and DIRECTION is non-`nil', DIRECTION must | |
750 | be \"out\"." | |
751 | ;; For methods, we use "in" as default direction. | |
752 | (let ((object (or (dbus-introspect-get-method | |
753 | bus service path interface name) | |
754 | (dbus-introspect-get-signal | |
755 | bus service path interface name)))) | |
756 | (when (and (string-equal | |
757 | "method" (dbus-introspect-get-attribute object "name")) | |
758 | (not (stringp direction))) | |
759 | (setq direction "in")) | |
760 | ;; In signals, no direction is given. | |
761 | (when (string-equal "signal" (dbus-introspect-get-attribute object "name")) | |
762 | (setq direction nil)) | |
763 | ;; Collect the signatures. | |
764 | (mapconcat | |
765 | '(lambda (x) | |
766 | (let ((arg (dbus-introspect-get-argument | |
767 | bus service path interface name x))) | |
768 | (if (or (not (stringp direction)) | |
769 | (string-equal | |
770 | direction | |
771 | (dbus-introspect-get-attribute arg "direction"))) | |
772 | (dbus-introspect-get-attribute arg "type") | |
773 | ""))) | |
774 | (dbus-introspect-get-argument-names bus service path interface name) | |
775 | ""))) | |
3a993e3d | 776 | |
f636d3ca MA |
777 | \f |
778 | ;;; D-Bus properties. | |
3a993e3d | 779 | |
f636d3ca MA |
780 | (defun dbus-get-property (bus service path interface property) |
781 | "Return the value of PROPERTY of INTERFACE. | |
782 | It will be checked at BUS, SERVICE, PATH. The result can be any | |
783 | valid D-Bus value, or `nil' if there is no PROPERTY." | |
246a286b | 784 | (dbus-ignore-errors |
f636d3ca MA |
785 | ;; We must check, whether the "org.freedesktop.DBus.Properties" |
786 | ;; interface is supported; otherwise the call blocks. | |
787 | (when | |
788 | (member | |
789 | "Get" | |
790 | (dbus-introspect-get-method-names | |
791 | bus service path "org.freedesktop.DBus.Properties")) | |
792 | ;; "Get" returns a variant, so we must use the car. | |
793 | (car | |
794 | (dbus-call-method | |
795 | bus service path dbus-interface-properties | |
796 | "Get" interface property))))) | |
797 | ||
798 | (defun dbus-set-property (bus service path interface property value) | |
799 | "Set value of PROPERTY of INTERFACE to VALUE. | |
800 | It will be checked at BUS, SERVICE, PATH. When the value has | |
801 | been set successful, the result is VALUE. Otherwise, `nil' is | |
802 | returned." | |
803 | (dbus-ignore-errors | |
804 | (when | |
805 | (and | |
806 | ;; We must check, whether the | |
807 | ;; "org.freedesktop.DBus.Properties" interface is supported; | |
808 | ;; otherwise the call blocks. | |
809 | (member | |
810 | "Set" | |
811 | (dbus-introspect-get-method-names | |
812 | bus service path "org.freedesktop.DBus.Properties")) | |
813 | ;; PROPERTY must be writable. | |
814 | (string-equal | |
815 | "readwrite" | |
816 | (dbus-introspect-get-attribute | |
ba0b66b0 | 817 | (dbus-introspect-get-property bus service path interface property) |
98c38bfc | 818 | "access"))) |
f636d3ca MA |
819 | ;; "Set" requires a variant. |
820 | (dbus-call-method | |
821 | bus service path dbus-interface-properties | |
822 | "Set" interface property (list :variant value)) | |
823 | ;; Return VALUE. | |
824 | (dbus-get-property bus service path interface property)))) | |
825 | ||
826 | (defun dbus-get-all-properties (bus service path interface) | |
827 | "Return all properties of INTERFACE at BUS, SERVICE, PATH. | |
828 | The result is a list of entries. Every entry is a cons of the | |
829 | name of the property, and its value. If there are no properties, | |
830 | `nil' is returned." | |
831 | ;; "org.freedesktop.DBus.Properties.GetAll" is not supported at | |
832 | ;; all interfaces. Therefore, we do it ourselves. | |
833 | (dbus-ignore-errors | |
834 | (let (result) | |
835 | (dolist (property | |
836 | (dbus-introspect-get-property-names | |
837 | bus service path interface) | |
838 | result) | |
839 | (add-to-list | |
840 | 'result | |
841 | (cons property (dbus-get-property bus service path interface property)) | |
842 | 'append))))) | |
3a993e3d MA |
843 | |
844 | (provide 'dbus) | |
845 | ||
79f10da0 | 846 | ;; arch-tag: a47caf84-9162-4811-90cc-5d388e37b9bd |
3a993e3d | 847 | ;;; dbus.el ends here |