• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /*
2  *
3  *  D-Bus helper library
4  *
5  *  Copyright (C) 2004-2010  Marcel Holtmann <marcel@holtmann.org>
6  *
7  *
8  *  This program is free software; you can redistribute it and/or modify
9  *  it under the terms of the GNU General Public License as published by
10  *  the Free Software Foundation; either version 2 of the License, or
11  *  (at your option) any later version.
12  *
13  *  This program is distributed in the hope that it will be useful,
14  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
15  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  *  GNU General Public License for more details.
17  *
18  *  You should have received a copy of the GNU General Public License
19  *  along with this program; if not, write to the Free Software
20  *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
21  *
22  */
23 
24 #ifdef HAVE_CONFIG_H
25 #include <config.h>
26 #endif
27 
28 #include <stdio.h>
29 #include <string.h>
30 
31 #include <glib.h>
32 #include <dbus/dbus.h>
33 
34 #include "gdbus.h"
35 
36 #define info(fmt...)
37 #define error(fmt...)
38 #define debug(fmt...)
39 
40 struct generic_data {
41 	unsigned int refcount;
42 	GSList *interfaces;
43 	char *introspect;
44 };
45 
46 struct interface_data {
47 	char *name;
48 	const GDBusMethodTable *methods;
49 	const GDBusSignalTable *signals;
50 	const GDBusPropertyTable *properties;
51 	void *user_data;
52 	GDBusDestroyFunction destroy;
53 };
54 
print_arguments(GString * gstr,const char * sig,const char * direction)55 static void print_arguments(GString *gstr, const char *sig,
56 						const char *direction)
57 {
58 	int i;
59 
60 	for (i = 0; sig[i]; i++) {
61 		char type[32];
62 		int struct_level, dict_level;
63 		unsigned int len;
64 		gboolean complete;
65 
66 		complete = FALSE;
67 		struct_level = dict_level = 0;
68 		memset(type, 0, sizeof(type));
69 
70 		/* Gather enough data to have a single complete type */
71 		for (len = 0; len < (sizeof(type) - 1) && sig[i]; len++, i++) {
72 			switch (sig[i]){
73 			case '(':
74 				struct_level++;
75 				break;
76 			case ')':
77 				struct_level--;
78 				if (struct_level <= 0 && dict_level <= 0)
79 					complete = TRUE;
80 				break;
81 			case '{':
82 				dict_level++;
83 				break;
84 			case '}':
85 				dict_level--;
86 				if (struct_level <= 0 && dict_level <= 0)
87 					complete = TRUE;
88 				break;
89 			case 'a':
90 				break;
91 			default:
92 				if (struct_level <= 0 && dict_level <= 0)
93 					complete = TRUE;
94 				break;
95 			}
96 
97 			type[len] = sig[i];
98 
99 			if (complete)
100 				break;
101 		}
102 
103 
104 		if (direction)
105 			g_string_append_printf(gstr,
106 					"\t\t\t<arg type=\"%s\" direction=\"%s\"/>\n",
107 					type, direction);
108 		else
109 			g_string_append_printf(gstr,
110 					"\t\t\t<arg type=\"%s\"/>\n",
111 					type);
112 	}
113 }
114 
generate_interface_xml(GString * gstr,struct interface_data * iface)115 static void generate_interface_xml(GString *gstr, struct interface_data *iface)
116 {
117 	const GDBusMethodTable *method;
118 	const GDBusSignalTable *signal;
119 
120 	for (method = iface->methods; method && method->name; method++) {
121 		if (!strlen(method->signature) && !strlen(method->reply))
122 			g_string_append_printf(gstr, "\t\t<method name=\"%s\"/>\n",
123 								method->name);
124 		else {
125 			g_string_append_printf(gstr, "\t\t<method name=\"%s\">\n",
126 								method->name);
127 			print_arguments(gstr, method->signature, "in");
128 			print_arguments(gstr, method->reply, "out");
129 			g_string_append_printf(gstr, "\t\t</method>\n");
130 		}
131 	}
132 
133 	for (signal = iface->signals; signal && signal->name; signal++) {
134 		if (!strlen(signal->signature))
135 			g_string_append_printf(gstr, "\t\t<signal name=\"%s\"/>\n",
136 								signal->name);
137 		else {
138 			g_string_append_printf(gstr, "\t\t<signal name=\"%s\">\n",
139 								signal->name);
140 			print_arguments(gstr, signal->signature, NULL);
141 			g_string_append_printf(gstr, "\t\t</signal>\n");
142 		}
143 	}
144 }
145 
generate_introspection_xml(DBusConnection * conn,struct generic_data * data,const char * path)146 static void generate_introspection_xml(DBusConnection *conn,
147 				struct generic_data *data, const char *path)
148 {
149 	GSList *list;
150 	GString *gstr;
151 	char **children;
152 	int i;
153 
154 	g_free(data->introspect);
155 
156 	gstr = g_string_new(DBUS_INTROSPECT_1_0_XML_DOCTYPE_DECL_NODE);
157 
158 	g_string_append_printf(gstr, "<node name=\"%s\">\n", path);
159 
160 	for (list = data->interfaces; list; list = list->next) {
161 		struct interface_data *iface = list->data;
162 
163 		g_string_append_printf(gstr, "\t<interface name=\"%s\">\n",
164 								iface->name);
165 
166 		generate_interface_xml(gstr, iface);
167 
168 		g_string_append_printf(gstr, "\t</interface>\n");
169 	}
170 
171 	if (!dbus_connection_list_registered(conn, path, &children))
172 		goto done;
173 
174 	for (i = 0; children[i]; i++)
175 		g_string_append_printf(gstr, "\t<node name=\"%s\"/>\n",
176 								children[i]);
177 
178 	dbus_free_string_array(children);
179 
180 done:
181 	g_string_append_printf(gstr, "</node>\n");
182 
183 	data->introspect = g_string_free(gstr, FALSE);
184 }
185 
introspect(DBusConnection * connection,DBusMessage * message,void * user_data)186 static DBusMessage *introspect(DBusConnection *connection,
187 				DBusMessage *message, void *user_data)
188 {
189 	struct generic_data *data = user_data;
190 	DBusMessage *reply;
191 
192 	if (!dbus_message_has_signature(message, DBUS_TYPE_INVALID_AS_STRING)) {
193 		error("Unexpected signature to introspect call");
194 		return NULL;
195 	}
196 
197 	if (!data->introspect)
198 		generate_introspection_xml(connection, data,
199 						dbus_message_get_path(message));
200 
201 	reply = dbus_message_new_method_return(message);
202 	if (!reply)
203 		return NULL;
204 
205 	dbus_message_append_args(reply, DBUS_TYPE_STRING, &data->introspect,
206 					DBUS_TYPE_INVALID);
207 
208 	return reply;
209 }
210 
generic_unregister(DBusConnection * connection,void * user_data)211 static void generic_unregister(DBusConnection *connection, void *user_data)
212 {
213 	struct generic_data *data = user_data;
214 
215 	g_free(data->introspect);
216 	g_free(data);
217 }
218 
find_interface(GSList * interfaces,const char * name)219 static struct interface_data *find_interface(GSList *interfaces,
220 						const char *name)
221 {
222 	GSList *list;
223 
224 	if (!name)
225 		return NULL;
226 
227 	for (list = interfaces; list; list = list->next) {
228 		struct interface_data *iface = list->data;
229 		if (!strcmp(name, iface->name))
230 			return iface;
231 	}
232 
233 	return NULL;
234 }
235 
generic_message(DBusConnection * connection,DBusMessage * message,void * user_data)236 static DBusHandlerResult generic_message(DBusConnection *connection,
237 					DBusMessage *message, void *user_data)
238 {
239 	struct generic_data *data = user_data;
240 	struct interface_data *iface;
241 	const GDBusMethodTable *method;
242 	const char *interface;
243 
244 	interface = dbus_message_get_interface(message);
245 
246 	iface = find_interface(data->interfaces, interface);
247 	if (!iface)
248 		return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
249 
250 	for (method = iface->methods; method &&
251 			method->name && method->function; method++) {
252 		DBusMessage *reply;
253 
254 		if (dbus_message_is_method_call(message, iface->name,
255 							method->name) == FALSE)
256 			continue;
257 
258 		if (dbus_message_has_signature(message,
259 						method->signature) == FALSE)
260 			continue;
261 
262 		reply = method->function(connection, message, iface->user_data);
263 
264 		if (method->flags & G_DBUS_METHOD_FLAG_NOREPLY) {
265 			if (reply != NULL)
266 				dbus_message_unref(reply);
267 			return DBUS_HANDLER_RESULT_HANDLED;
268 		}
269 
270 		if (method->flags & G_DBUS_METHOD_FLAG_ASYNC) {
271 			if (reply == NULL)
272 				return DBUS_HANDLER_RESULT_HANDLED;
273 		}
274 
275 		if (reply == NULL)
276 			return DBUS_HANDLER_RESULT_NEED_MEMORY;
277 
278 		dbus_connection_send(connection, reply, NULL);
279 		dbus_message_unref(reply);
280 
281 		return DBUS_HANDLER_RESULT_HANDLED;
282 	}
283 
284 	return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
285 }
286 
287 static DBusObjectPathVTable generic_table = {
288 	.unregister_function	= generic_unregister,
289 	.message_function	= generic_message,
290 };
291 
invalidate_parent_data(DBusConnection * conn,const char * child_path)292 static void invalidate_parent_data(DBusConnection *conn, const char *child_path)
293 {
294 	struct generic_data *data = NULL;
295 	char *parent_path, *slash;
296 
297 	parent_path = g_strdup(child_path);
298 	slash = strrchr(parent_path, '/');
299 	if (!slash)
300 		goto done;
301 
302 	if (slash == parent_path && parent_path[1] != '\0')
303 		parent_path[1] = '\0';
304 	else
305 		*slash = '\0';
306 
307 	if (!strlen(parent_path))
308 		goto done;
309 
310 	if (!dbus_connection_get_object_path_data(conn, parent_path,
311 							(void *) &data)) {
312 		invalidate_parent_data(conn, parent_path);
313 		goto done;
314 	}
315 
316 	if (!data)
317 		goto done;
318 
319 	g_free(data->introspect);
320 	data->introspect = NULL;
321 
322 done:
323 	g_free(parent_path);
324 }
325 
326 static GDBusMethodTable introspect_methods[] = {
327 	{ "Introspect",	"",	"s", introspect	},
328 	{ }
329 };
330 
add_interface(struct generic_data * data,const char * name,const GDBusMethodTable * methods,const GDBusSignalTable * signals,const GDBusPropertyTable * properties,void * user_data,GDBusDestroyFunction destroy)331 static void add_interface(struct generic_data *data, const char *name,
332 				const GDBusMethodTable *methods,
333 				const GDBusSignalTable *signals,
334 				const GDBusPropertyTable *properties,
335 				void *user_data,
336 				GDBusDestroyFunction destroy)
337 {
338 	struct interface_data *iface;
339 
340 	iface = g_new0(struct interface_data, 1);
341 	iface->name = g_strdup(name);
342 	iface->methods = methods;
343 	iface->signals = signals;
344 	iface->properties = properties;
345 	iface->user_data = user_data;
346 	iface->destroy = destroy;
347 
348 	data->interfaces = g_slist_append(data->interfaces, iface);
349 }
350 
object_path_ref(DBusConnection * connection,const char * path)351 static struct generic_data *object_path_ref(DBusConnection *connection,
352 							const char *path)
353 {
354 	struct generic_data *data;
355 
356 	if (dbus_connection_get_object_path_data(connection, path,
357 						(void *) &data) == TRUE) {
358 		if (data != NULL) {
359 			data->refcount++;
360 			return data;
361 		}
362 	}
363 
364 	data = g_new0(struct generic_data, 1);
365 
366 	data->introspect = g_strdup(DBUS_INTROSPECT_1_0_XML_DOCTYPE_DECL_NODE "<node></node>");
367 
368 	data->refcount = 1;
369 
370 	if (!dbus_connection_register_object_path(connection, path,
371 						&generic_table, data)) {
372 		g_free(data->introspect);
373 		g_free(data);
374 		return NULL;
375 	}
376 
377 	invalidate_parent_data(connection, path);
378 
379 	add_interface(data, DBUS_INTERFACE_INTROSPECTABLE,
380 			introspect_methods, NULL, NULL, data, NULL);
381 
382 	return data;
383 }
384 
remove_interface(struct generic_data * data,const char * name)385 static gboolean remove_interface(struct generic_data *data, const char *name)
386 {
387 	struct interface_data *iface;
388 
389 	iface = find_interface(data->interfaces, name);
390 	if (!iface)
391 		return FALSE;
392 
393 	data->interfaces = g_slist_remove(data->interfaces, iface);
394 
395 	if (iface->destroy)
396 		iface->destroy(iface->user_data);
397 
398 	g_free(iface->name);
399 	g_free(iface);
400 
401 	return TRUE;
402 }
403 
object_path_unref(DBusConnection * connection,const char * path)404 static void object_path_unref(DBusConnection *connection, const char *path)
405 {
406 	struct generic_data *data = NULL;
407 
408 	if (dbus_connection_get_object_path_data(connection, path,
409 						(void *) &data) == FALSE)
410 		return;
411 
412 	if (data == NULL)
413 		return;
414 
415 	data->refcount--;
416 
417 	if (data->refcount > 0)
418 		return;
419 
420 	remove_interface(data, DBUS_INTERFACE_INTROSPECTABLE);
421 
422 	invalidate_parent_data(connection, path);
423 
424 	dbus_connection_unregister_object_path(connection, path);
425 }
426 
check_signal(DBusConnection * conn,const char * path,const char * interface,const char * name,const char ** args)427 static gboolean check_signal(DBusConnection *conn, const char *path,
428 				const char *interface, const char *name,
429 				const char **args)
430 {
431 	struct generic_data *data = NULL;
432 	struct interface_data *iface;
433 	const GDBusSignalTable *signal;
434 
435 	*args = NULL;
436 	if (!dbus_connection_get_object_path_data(conn, path,
437 					(void *) &data) || !data) {
438 		error("dbus_connection_emit_signal: path %s isn't registered",
439 				path);
440 		return FALSE;
441 	}
442 
443 	iface = find_interface(data->interfaces, interface);
444 	if (!iface) {
445 		error("dbus_connection_emit_signal: %s does not implement %s",
446 				path, interface);
447 		return FALSE;
448 	}
449 
450 	for (signal = iface->signals; signal && signal->name; signal++) {
451 		if (!strcmp(signal->name, name)) {
452 			*args = signal->signature;
453 			break;
454 		}
455 	}
456 
457 	if (!*args) {
458 		error("No signal named %s on interface %s", name, interface);
459 		return FALSE;
460 	}
461 
462 	return TRUE;
463 }
464 
emit_signal_valist(DBusConnection * conn,const char * path,const char * interface,const char * name,int first,va_list var_args)465 static dbus_bool_t emit_signal_valist(DBusConnection *conn,
466 						const char *path,
467 						const char *interface,
468 						const char *name,
469 						int first,
470 						va_list var_args)
471 {
472 	DBusMessage *signal;
473 	dbus_bool_t ret;
474 	const char *signature, *args;
475 
476 	if (!check_signal(conn, path, interface, name, &args))
477 		return FALSE;
478 
479 	signal = dbus_message_new_signal(path, interface, name);
480 	if (!signal) {
481 		error("Unable to allocate new %s.%s signal", interface,  name);
482 		return FALSE;
483 	}
484 
485 	ret = dbus_message_append_args_valist(signal, first, var_args);
486 	if (!ret)
487 		goto fail;
488 
489 	signature = dbus_message_get_signature(signal);
490 	if (strcmp(args, signature) != 0) {
491 		error("%s.%s: expected signature'%s' but got '%s'",
492 				interface, name, args, signature);
493 		ret = FALSE;
494 		goto fail;
495 	}
496 
497 	ret = dbus_connection_send(conn, signal, NULL);
498 
499 fail:
500 	dbus_message_unref(signal);
501 
502 	return ret;
503 }
504 
g_dbus_register_interface(DBusConnection * connection,const char * path,const char * name,const GDBusMethodTable * methods,const GDBusSignalTable * signals,const GDBusPropertyTable * properties,void * user_data,GDBusDestroyFunction destroy)505 gboolean g_dbus_register_interface(DBusConnection *connection,
506 					const char *path, const char *name,
507 					const GDBusMethodTable *methods,
508 					const GDBusSignalTable *signals,
509 					const GDBusPropertyTable *properties,
510 					void *user_data,
511 					GDBusDestroyFunction destroy)
512 {
513 	struct generic_data *data;
514 
515 	data = object_path_ref(connection, path);
516 	if (data == NULL)
517 		return FALSE;
518 
519 	if (find_interface(data->interfaces, name)) {
520 		object_path_unref(connection, path);
521 		return FALSE;
522 	}
523 
524 	add_interface(data, name, methods, signals,
525 			properties, user_data, destroy);
526 
527 	g_free(data->introspect);
528 	data->introspect = NULL;
529 
530 	return TRUE;
531 }
532 
g_dbus_unregister_interface(DBusConnection * connection,const char * path,const char * name)533 gboolean g_dbus_unregister_interface(DBusConnection *connection,
534 					const char *path, const char *name)
535 {
536 	struct generic_data *data = NULL;
537 
538 	if (!path)
539 		return FALSE;
540 
541 	if (dbus_connection_get_object_path_data(connection, path,
542 						(void *) &data) == FALSE)
543 		return FALSE;
544 
545 	if (data == NULL)
546 		return FALSE;
547 
548 	if (remove_interface(data, name) == FALSE)
549 		return FALSE;
550 
551 	g_free(data->introspect);
552 	data->introspect = NULL;
553 
554 	object_path_unref(connection, path);
555 
556 	return TRUE;
557 }
558 
g_dbus_create_error_valist(DBusMessage * message,const char * name,const char * format,va_list args)559 DBusMessage *g_dbus_create_error_valist(DBusMessage *message, const char *name,
560 					const char *format, va_list args)
561 {
562 	char str[1024];
563 
564 	vsnprintf(str, sizeof(str), format, args);
565 
566 	return dbus_message_new_error(message, name, str);
567 }
568 
g_dbus_create_error(DBusMessage * message,const char * name,const char * format,...)569 DBusMessage *g_dbus_create_error(DBusMessage *message, const char *name,
570 						const char *format, ...)
571 {
572 	va_list args;
573 	DBusMessage *reply;
574 
575 	va_start(args, format);
576 
577 	reply = g_dbus_create_error_valist(message, name, format, args);
578 
579 	va_end(args);
580 
581 	return reply;
582 }
583 
g_dbus_create_reply_valist(DBusMessage * message,int type,va_list args)584 DBusMessage *g_dbus_create_reply_valist(DBusMessage *message,
585 						int type, va_list args)
586 {
587 	DBusMessage *reply;
588 
589 	reply = dbus_message_new_method_return(message);
590 	if (reply == NULL)
591 		return NULL;
592 
593 	if (dbus_message_append_args_valist(reply, type, args) == FALSE) {
594 		dbus_message_unref(reply);
595 		return NULL;
596 	}
597 
598 	return reply;
599 }
600 
g_dbus_create_reply(DBusMessage * message,int type,...)601 DBusMessage *g_dbus_create_reply(DBusMessage *message, int type, ...)
602 {
603 	va_list args;
604 	DBusMessage *reply;
605 
606 	va_start(args, type);
607 
608 	reply = g_dbus_create_reply_valist(message, type, args);
609 
610 	va_end(args);
611 
612 	return reply;
613 }
614 
g_dbus_send_message(DBusConnection * connection,DBusMessage * message)615 gboolean g_dbus_send_message(DBusConnection *connection, DBusMessage *message)
616 {
617 	dbus_bool_t result;
618 
619 	if (dbus_message_get_type(message) == DBUS_MESSAGE_TYPE_METHOD_CALL)
620 		dbus_message_set_no_reply(message, TRUE);
621 
622 	result = dbus_connection_send(connection, message, NULL);
623 
624 	dbus_message_unref(message);
625 
626 	return result;
627 }
628 
g_dbus_send_reply_valist(DBusConnection * connection,DBusMessage * message,int type,va_list args)629 gboolean g_dbus_send_reply_valist(DBusConnection *connection,
630 				DBusMessage *message, int type, va_list args)
631 {
632 	DBusMessage *reply;
633 
634 	reply = dbus_message_new_method_return(message);
635 	if (reply == NULL)
636 		return FALSE;
637 
638 	if (dbus_message_append_args_valist(reply, type, args) == FALSE) {
639 		dbus_message_unref(reply);
640 		return FALSE;
641 	}
642 
643 	return g_dbus_send_message(connection, reply);
644 }
645 
g_dbus_send_reply(DBusConnection * connection,DBusMessage * message,int type,...)646 gboolean g_dbus_send_reply(DBusConnection *connection,
647 				DBusMessage *message, int type, ...)
648 {
649 	va_list args;
650 	gboolean result;
651 
652 	va_start(args, type);
653 
654 	result = g_dbus_send_reply_valist(connection, message, type, args);
655 
656 	va_end(args);
657 
658 	return result;
659 }
660 
g_dbus_emit_signal(DBusConnection * connection,const char * path,const char * interface,const char * name,int type,...)661 gboolean g_dbus_emit_signal(DBusConnection *connection,
662 				const char *path, const char *interface,
663 				const char *name, int type, ...)
664 {
665 	va_list args;
666 	gboolean result;
667 
668 	va_start(args, type);
669 
670 	result = emit_signal_valist(connection, path, interface,
671 							name, type, args);
672 
673 	va_end(args);
674 
675 	return result;
676 }
677 
g_dbus_emit_signal_valist(DBusConnection * connection,const char * path,const char * interface,const char * name,int type,va_list args)678 gboolean g_dbus_emit_signal_valist(DBusConnection *connection,
679 				const char *path, const char *interface,
680 				const char *name, int type, va_list args)
681 {
682 	return emit_signal_valist(connection, path, interface,
683 							name, type, args);
684 }
685