1 /* 2 * 3 * D-Bus helper library 4 * 5 * Copyright (C) 2004-2010 Marcel Holtmann <marcel (at) 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 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 } 114 115 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 } 145 146 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 } 185 186 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 } 210 211 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 } 218 219 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 } 235 236 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 }; 291 292 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 }; 330 331 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 } 350 351 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 } 384 385 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 } 403 404 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 } 426 427 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 } 464 465 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 } 504 505 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 } 532 533 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 } 558 559 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 } 568 569 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 } 583 584 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 } 600 601 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 } 614 615 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 } 628 629 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 } 645 646 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 } 660 661 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 } 677 678 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