git.meshlink.io Git - catta/blob - avahi-client/client.c

   1 /* $Id$ */
   2
   3 /***
   4   This file is part of avahi.
   5
   6   avahi is free software; you can redistribute it and/or modify it
   7   under the terms of the GNU Lesser General Public License as
   8   published by the Free Software Foundation; either version 2.1 of the
   9   License, or (at your option) any later version.
  10
  11   avahi is distributed in the hope that it will be useful, but WITHOUT
  12   ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  13   or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General
  14   Public License for more details.
  15
  16   You should have received a copy of the GNU Lesser General Public
  17   License along with avahi; if not, write to the Free Software
  18   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  19   USA.
  20 ***/
  21
  22 #ifdef HAVE_CONFIG_H
  23 #include <config.h>
  24 #endif
  25
  26 #include <stdlib.h>
  27 #include <stdio.h>
  28 #include <string.h>
  29
  30 #include <dbus/dbus.h>
  31
  32 #include <avahi-common/dbus.h>
  33 #include <avahi-common/llist.h>
  34 #include <avahi-common/error.h>
  35 #include <avahi-common/dbus.h>
  36 #include <avahi-common/malloc.h>
  37 #include <avahi-common/dbus-watch-glue.h>
  38
  39 #include "client.h"
  40 #include "internal.h"
  41
  42 int avahi_client_set_errno (AvahiClient *client, int error) {
  43     assert(client);
  44
  45     return client->error = error;
  46 }
  47
  48 int avahi_client_set_dbus_error(AvahiClient *client, DBusError *error) {
  49     assert(client);
  50     assert(error);
  51
  52     return avahi_client_set_errno(client, avahi_error_dbus_to_number(error->name));
  53 }
  54
  55 static void client_set_state (AvahiClient *client, AvahiServerState state) {
  56     assert(client);
  57
  58     if (client->state == state)
  59         return;
  60
  61     client->state = state;
  62
  63     switch (client->state) {
  64         case AVAHI_CLIENT_DISCONNECTED:
  65             if (client->bus) {
  66                 dbus_connection_disconnect(client->bus);
  67                 dbus_connection_unref(client->bus);
  68                 client->bus = NULL;
  69             }
  70
  71             /* Fall through */
  72
  73         case AVAHI_CLIENT_S_COLLISION:
  74         case AVAHI_CLIENT_S_REGISTERING:
  75
  76             /* Clear cached strings */
  77             avahi_free(client->host_name);
  78             avahi_free(client->host_name_fqdn);
  79             avahi_free(client->domain_name);
  80
  81             client->host_name =  NULL;
  82             client->host_name_fqdn = NULL;
  83             client->domain_name = NULL;
  84             break;
  85
  86         case AVAHI_CLIENT_S_INVALID:
  87         case AVAHI_CLIENT_S_RUNNING:
  88             break;
  89
  90     }
  91
  92     if (client->callback)
  93         client->callback (client, state, client->userdata);
  94 }
  95
  96 static DBusHandlerResult filter_func(DBusConnection *bus, DBusMessage *message, void *userdata) {
  97     AvahiClient *client = userdata;
  98     DBusError error;
  99
 100     assert(bus);
 101     assert(message);
 102
 103     dbus_error_init (&error);
 104
 105 /*     fprintf(stderr, "dbus: interface=%s, path=%s, member=%s\n", */
 106 /*             dbus_message_get_interface (message), */
 107 /*             dbus_message_get_path (message), */
 108 /*             dbus_message_get_member (message)); */
 109
 110     if (client->state == AVAHI_CLIENT_DISCONNECTED)
 111         goto fail;
 112
 113     if (dbus_message_is_signal(message, DBUS_INTERFACE_LOCAL, "Disconnected")) {
 114
 115         /* The DBUS server died or kicked us */
 116         client_set_state(client, AVAHI_CLIENT_DISCONNECTED);
 117
 118     } if (dbus_message_is_signal(message, DBUS_INTERFACE_DBUS, "NameOwnerChanged")) {
 119         char *name, *old, *new;
 120
 121         if (!(dbus_message_get_args(
 122                   message, &error,
 123                   DBUS_TYPE_STRING, &name,
 124                   DBUS_TYPE_STRING, &old,
 125                   DBUS_TYPE_STRING, &new,
 126                   DBUS_TYPE_INVALID) || dbus_error_is_set (&error))) {
 127
 128             fprintf(stderr, "WARNING: Failed to parse NameOwnerChanged signal: %s\n", error.message);
 129             goto fail;
 130         }
 131
 132         if (strcmp(name, AVAHI_DBUS_NAME) == 0)
 133
 134             /* Regardless if the server lost or acquired its name or
 135              * if the name was transfered: our services are no longer
 136              * available, so we disconnect ourselves */
 137
 138             client_set_state(client, AVAHI_CLIENT_DISCONNECTED);
 139
 140     } else if (dbus_message_is_signal (message, AVAHI_DBUS_INTERFACE_SERVER, "StateChanged")) {
 141         int32_t state;
 142
 143         if (!(dbus_message_get_args(
 144                   message, &error,
 145                   DBUS_TYPE_INT32, &state,
 146                   DBUS_TYPE_INVALID) || dbus_error_is_set (&error))) {
 147             fprintf(stderr, "WARNING: Failed to parse Server.StateChanged signal: %s\n", error.message);
 148             goto fail;
 149         }
 150
 151         client_set_state(client, (AvahiClientState) state);
 152
 153     } else if (dbus_message_is_signal (message, AVAHI_DBUS_INTERFACE_ENTRY_GROUP, "StateChanged")) {
 154         const char *path;
 155         AvahiEntryGroup *g;
 156         path = dbus_message_get_path(message);
 157
 158         for (g = client->groups; g; g = g->groups_next)
 159             if (strcmp(g->path, path) == 0)
 160                 break;
 161
 162         if (g) {
 163             int32_t state;
 164             if (!(dbus_message_get_args (message, &error, DBUS_TYPE_INT32, &state, DBUS_TYPE_INVALID)) ||
 165                 dbus_error_is_set(&error)) {
 166                 fprintf(stderr, "WARNING: Failed to parse EntryGroup.StateChanged signal: %s\n", error.message);
 167                 goto fail;
 168             }
 169
 170             avahi_entry_group_set_state(g, state);
 171         }
 172
 173     } else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_DOMAIN_BROWSER, "ItemNew"))
 174         return avahi_domain_browser_event(client, AVAHI_BROWSER_NEW, message);
 175     else if (dbus_message_is_signal (message, AVAHI_DBUS_INTERFACE_DOMAIN_BROWSER, "ItemRemove"))
 176         return avahi_domain_browser_event(client, AVAHI_BROWSER_REMOVE, message);
 177     else if (dbus_message_is_signal (message, AVAHI_DBUS_INTERFACE_DOMAIN_BROWSER, "CacheExhausted"))
 178         return avahi_domain_browser_event(client, AVAHI_BROWSER_CACHE_EXHAUSTED, message);
 179     else if (dbus_message_is_signal (message, AVAHI_DBUS_INTERFACE_DOMAIN_BROWSER, "AllForNow"))
 180         return avahi_domain_browser_event(client, AVAHI_BROWSER_ALL_FOR_NOW, message);
 181     else if (dbus_message_is_signal (message, AVAHI_DBUS_INTERFACE_DOMAIN_BROWSER, "Failure"))
 182         return avahi_domain_browser_event(client, AVAHI_BROWSER_FAILURE, message);
 183
 184     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_SERVICE_TYPE_BROWSER, "ItemNew"))
 185         return avahi_service_type_browser_event (client, AVAHI_BROWSER_NEW, message);
 186     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_SERVICE_TYPE_BROWSER, "ItemRemove"))
 187         return avahi_service_type_browser_event (client, AVAHI_BROWSER_REMOVE, message);
 188     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_SERVICE_TYPE_BROWSER, "CacheExhausted"))
 189         return avahi_service_type_browser_event (client, AVAHI_BROWSER_CACHE_EXHAUSTED, message);
 190     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_SERVICE_TYPE_BROWSER, "AllForNow"))
 191         return avahi_service_type_browser_event (client, AVAHI_BROWSER_ALL_FOR_NOW, message);
 192     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_SERVICE_TYPE_BROWSER, "Failure"))
 193         return avahi_service_type_browser_event (client, AVAHI_BROWSER_FAILURE, message);
 194
 195     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_SERVICE_BROWSER, "ItemNew"))
 196         return avahi_service_browser_event (client, AVAHI_BROWSER_NEW, message);
 197     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_SERVICE_BROWSER, "ItemRemove"))
 198         return avahi_service_browser_event (client, AVAHI_BROWSER_REMOVE, message);
 199     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_SERVICE_BROWSER, "CacheExhausted"))
 200         return avahi_service_browser_event (client, AVAHI_BROWSER_CACHE_EXHAUSTED, message);
 201     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_SERVICE_BROWSER, "AllForNow"))
 202         return avahi_service_browser_event (client, AVAHI_BROWSER_ALL_FOR_NOW, message);
 203     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_SERVICE_BROWSER, "Failure"))
 204         return avahi_service_browser_event (client, AVAHI_BROWSER_FAILURE, message);
 205
 206     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_SERVICE_RESOLVER, "Found"))
 207         return avahi_service_resolver_event (client, AVAHI_RESOLVER_FOUND, message);
 208     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_SERVICE_RESOLVER, "Failure"))
 209         return avahi_service_resolver_event (client, AVAHI_RESOLVER_FAILURE, message);
 210
 211     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_HOST_NAME_RESOLVER, "Found"))
 212         return avahi_host_name_resolver_event (client, AVAHI_RESOLVER_FOUND, message);
 213     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_HOST_NAME_RESOLVER, "Failure"))
 214         return avahi_host_name_resolver_event (client, AVAHI_RESOLVER_FAILURE, message);
 215
 216     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_ADDRESS_RESOLVER, "Found"))
 217         return avahi_address_resolver_event (client, AVAHI_RESOLVER_FOUND, message);
 218     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_ADDRESS_RESOLVER, "Failure"))
 219         return avahi_address_resolver_event (client, AVAHI_RESOLVER_FAILURE, message);
 220
 221     return DBUS_HANDLER_RESULT_HANDLED;
 222
 223 fail:
 224
 225     dbus_error_free (&error);
 226     return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
 227 }
 228
 229 static int get_server_state(AvahiClient *client, int *ret_error) {
 230     DBusMessage *message = NULL, *reply = NULL;
 231     DBusError error;
 232     int32_t state;
 233     int e = AVAHI_ERR_NO_MEMORY;
 234
 235     assert(client);
 236
 237     dbus_error_init(&error);
 238
 239     if (!(message = dbus_message_new_method_call(AVAHI_DBUS_NAME, AVAHI_DBUS_PATH_SERVER, AVAHI_DBUS_INTERFACE_SERVER, "GetState")))
 240         goto fail;
 241
 242     reply = dbus_connection_send_with_reply_and_block (client->bus, message, -1, &error);
 243
 244     if (!reply || dbus_error_is_set (&error))
 245         goto fail;
 246
 247     if (!(dbus_message_get_args(reply, &error, DBUS_TYPE_INT32, &state, DBUS_TYPE_INVALID)) ||
 248         dbus_error_is_set (&error))
 249         goto fail;
 250
 251     client_set_state(client, (AvahiServerState) state);
 252
 253     dbus_message_unref(message);
 254     dbus_message_unref(reply);
 255
 256     return AVAHI_OK;
 257
 258 fail:
 259     if (dbus_error_is_set(&error)) {
 260         e = avahi_error_dbus_to_number (error.name);
 261         dbus_error_free(&error);
 262     }
 263
 264     if (ret_error)
 265         *ret_error = e;
 266
 267     if (message)
 268         dbus_message_unref(message);
 269     if (reply)
 270         dbus_message_unref(reply);
 271
 272     return e;
 273 }
 274
 275 static int check_version(AvahiClient *client, int *ret_error) {
 276     DBusMessage *message = NULL, *reply  = NULL;
 277     DBusError error;
 278     char *version;
 279     int e = AVAHI_ERR_NO_MEMORY;
 280
 281     assert(client);
 282
 283     dbus_error_init(&error);
 284
 285     if (!(message = dbus_message_new_method_call(AVAHI_DBUS_NAME, AVAHI_DBUS_PATH_SERVER, AVAHI_DBUS_INTERFACE_SERVER, "GetVersionString")))
 286         goto fail;
 287
 288     reply = dbus_connection_send_with_reply_and_block (client->bus, message, -1, &error);
 289
 290     if (!reply || dbus_error_is_set (&error))
 291         goto fail;
 292
 293     if (!dbus_message_get_args (reply, &error, DBUS_TYPE_STRING, &version, DBUS_TYPE_INVALID) ||
 294         dbus_error_is_set (&error))
 295         goto fail;
 296
 297     if (strcmp(version, PACKAGE_STRING) != 0) {
 298         e = AVAHI_ERR_VERSION_MISMATCH;
 299         goto fail;
 300     }
 301
 302     dbus_message_unref(message);
 303     dbus_message_unref(reply);
 304
 305     return AVAHI_OK;
 306
 307 fail:
 308     if (dbus_error_is_set(&error)) {
 309         e = avahi_error_dbus_to_number (error.name);
 310         dbus_error_free(&error);
 311     }
 312
 313     if (ret_error)
 314         *ret_error = e;
 315
 316     if (message)
 317         dbus_message_unref(message);
 318     if (reply)
 319         dbus_message_unref(reply);
 320
 321     return e;
 322 }
 323
 324
 325 /* This function acts like dbus_bus_get but creates a private
 326  * connection instead */
 327 static DBusConnection*
 328 avahi_dbus_bus_get (DBusError *error)
 329 {
 330     DBusConnection *conn;
 331     const char *env_addr;
 332
 333     env_addr = getenv ("DBUS_SYSTEM_BUS_ADDRESS");
 334
 335     if (env_addr == NULL || (*env_addr == 0))
 336     {
 337         env_addr = DBUS_SYSTEM_BUS_DEFAULT_ADDRESS;
 338     }
 339
 340     conn = dbus_connection_open_private (env_addr, error);
 341
 342     if (!conn)
 343         return NULL;
 344
 345     dbus_connection_set_exit_on_disconnect (conn, FALSE);
 346
 347     if (!dbus_bus_register (conn, error))
 348     {
 349         dbus_connection_close (conn);
 350         dbus_connection_unref (conn);
 351
 352         return NULL;
 353     }
 354
 355     return conn;
 356 }
 357
 358 AvahiClient *avahi_client_new(const AvahiPoll *poll_api, AvahiClientCallback callback, void *userdata, int *ret_error) {
 359     AvahiClient *client = NULL;
 360     DBusError error;
 361
 362     dbus_error_init (&error);
 363
 364     if (!(client = avahi_new(AvahiClient, 1))) {
 365         if (ret_error)
 366             *ret_error = AVAHI_ERR_NO_MEMORY;
 367         goto fail;
 368     }
 369
 370     client->poll_api = poll_api;
 371     client->error = AVAHI_OK;
 372     client->callback = callback;
 373     client->userdata = userdata;
 374     client->state = AVAHI_CLIENT_DISCONNECTED;
 375
 376     client->host_name = NULL;
 377     client->host_name_fqdn = NULL;
 378     client->domain_name = NULL;
 379     client->version_string = NULL;
 380     client->local_service_cookie_valid = 0;
 381
 382     AVAHI_LLIST_HEAD_INIT(AvahiEntryGroup, client->groups);
 383     AVAHI_LLIST_HEAD_INIT(AvahiDomainBrowser, client->domain_browsers);
 384     AVAHI_LLIST_HEAD_INIT(AvahiServiceBrowser, client->service_browsers);
 385     AVAHI_LLIST_HEAD_INIT(AvahiServiceTypeBrowser, client->service_type_browsers);
 386     AVAHI_LLIST_HEAD_INIT(AvahiServiceResolver, client->service_resolvers);
 387     AVAHI_LLIST_HEAD_INIT(AvahiHostNameResolver, client->host_name_resolvers);
 388     AVAHI_LLIST_HEAD_INIT(AvahiAddressResolver, client->address_resolvers);
 389
 390     if (!(client->bus = avahi_dbus_bus_get(&error)) ||
 391         dbus_error_is_set (&error))
 392         goto fail;
 393
 394     if (avahi_dbus_connection_glue(client->bus, poll_api) < 0) {
 395         if (ret_error)
 396             *ret_error = AVAHI_ERR_NO_MEMORY; /* Not optimal */
 397         goto fail;
 398     }
 399
 400     if (!dbus_connection_add_filter (client->bus, filter_func, client, NULL)) {
 401         if (ret_error)
 402             *ret_error = AVAHI_ERR_NO_MEMORY;
 403         goto fail;
 404     }
 405
 406     dbus_bus_add_match(
 407         client->bus,
 408         "type='signal', "
 409         "interface='" AVAHI_DBUS_INTERFACE_SERVER "', "
 410         "sender='" AVAHI_DBUS_NAME "', "
 411         "path='" AVAHI_DBUS_PATH_SERVER "'",
 412         &error);
 413
 414     if (dbus_error_is_set (&error))
 415         goto fail;
 416
 417     dbus_bus_add_match (
 418         client->bus,
 419         "type='signal', "
 420         "interface='" DBUS_INTERFACE_DBUS "', "
 421         "sender='" DBUS_SERVICE_DBUS "', "
 422         "path='" DBUS_PATH_DBUS "'",
 423         &error);
 424
 425     if (dbus_error_is_set (&error))
 426         goto fail;
 427
 428         dbus_bus_add_match (
 429         client->bus,
 430         "type='signal', "
 431         "interface='" DBUS_INTERFACE_LOCAL "'",
 432         &error);
 433
 434     if (dbus_error_is_set (&error))
 435         goto fail;
 436
 437     if (!(dbus_bus_name_has_owner(client->bus, AVAHI_DBUS_NAME, &error)) ||
 438         dbus_error_is_set(&error)) {
 439
 440         /* We free the error so its not set, that way the fail target
 441          * will return the NO_DAEMON error rather than a DBUS error */
 442         dbus_error_free (&error);
 443
 444         if (ret_error)
 445             *ret_error = AVAHI_ERR_NO_DAEMON;
 446
 447         goto fail;
 448     }
 449
 450     if (check_version(client, ret_error) < 0)
 451         goto fail;
 452
 453     if (get_server_state(client, ret_error) < 0)
 454         goto fail;
 455
 456     return client;
 457
 458 fail:
 459
 460     if (client)
 461         avahi_client_free(client);
 462
 463     if (dbus_error_is_set(&error)) {
 464
 465         if (ret_error)
 466             *ret_error = avahi_error_dbus_to_number(error.name);
 467
 468         dbus_error_free(&error);
 469     }
 470
 471     return NULL;
 472 }
 473
 474 void avahi_client_free(AvahiClient *client) {
 475     assert(client);
 476
 477     while (client->groups)
 478         avahi_entry_group_free(client->groups);
 479
 480     while (client->domain_browsers)
 481         avahi_domain_browser_free(client->domain_browsers);
 482
 483     while (client->service_browsers)
 484         avahi_service_browser_free(client->service_browsers);
 485
 486     while (client->service_type_browsers)
 487         avahi_service_type_browser_free(client->service_type_browsers);
 488
 489     while (client->service_resolvers)
 490         avahi_service_resolver_free(client->service_resolvers);
 491
 492     if (client->bus) {
 493         dbus_connection_disconnect(client->bus);
 494         dbus_connection_unref(client->bus);
 495     }
 496
 497     avahi_free(client->version_string);
 498     avahi_free(client->host_name);
 499     avahi_free(client->host_name_fqdn);
 500     avahi_free(client->domain_name);
 501
 502     avahi_free(client);
 503 }
 504
 505 static char* avahi_client_get_string_reply_and_block (AvahiClient *client, const char *method, const char *param) {
 506     DBusMessage *message = NULL, *reply = NULL;
 507     DBusError error;
 508     char *ret, *n;
 509
 510     assert(client);
 511     assert(method);
 512
 513     dbus_error_init (&error);
 514
 515     if (!(message = dbus_message_new_method_call (AVAHI_DBUS_NAME, AVAHI_DBUS_PATH_SERVER, AVAHI_DBUS_INTERFACE_SERVER, method))) {
 516         avahi_client_set_errno(client, AVAHI_ERR_NO_MEMORY);
 517         goto fail;
 518     }
 519
 520     if (param) {
 521         if (!dbus_message_append_args (message, DBUS_TYPE_STRING, &param, DBUS_TYPE_INVALID)) {
 522             avahi_client_set_errno (client, AVAHI_ERR_NO_MEMORY);
 523             goto fail;
 524         }
 525     }
 526
 527     reply = dbus_connection_send_with_reply_and_block (client->bus, message, -1, &error);
 528
 529     if (!reply || dbus_error_is_set (&error))
 530         goto fail;
 531
 532     if (!dbus_message_get_args (reply, &error, DBUS_TYPE_STRING, &ret, DBUS_TYPE_INVALID) ||
 533         dbus_error_is_set (&error))
 534         goto fail;
 535
 536     if (!(n = avahi_strdup(ret))) {
 537         avahi_client_set_errno(client, AVAHI_ERR_NO_MEMORY);
 538         goto fail;
 539     }
 540
 541     dbus_message_unref(message);
 542     dbus_message_unref(reply);
 543
 544     return n;
 545
 546 fail:
 547
 548     if (message)
 549         dbus_message_unref(message);
 550     if (reply)
 551         dbus_message_unref(reply);
 552
 553     if (dbus_error_is_set(&error)) {
 554         avahi_client_set_dbus_error(client, &error);
 555         dbus_error_free(&error);
 556     }
 557
 558     return NULL;
 559 }
 560
 561 const char* avahi_client_get_version_string (AvahiClient *client) {
 562     assert(client);
 563
 564     if (client->state == AVAHI_CLIENT_DISCONNECTED) {
 565         avahi_client_set_errno(client, AVAHI_ERR_BAD_STATE);
 566         return NULL;
 567     }
 568
 569     if (!client->version_string)
 570         client->version_string = avahi_client_get_string_reply_and_block(client, "GetVersionString", NULL);
 571
 572     return client->version_string;
 573 }
 574
 575 const char* avahi_client_get_domain_name (AvahiClient *client) {
 576     assert(client);
 577
 578     if (client->state == AVAHI_CLIENT_DISCONNECTED) {
 579         avahi_client_set_errno(client, AVAHI_ERR_BAD_STATE);
 580         return NULL;
 581     }
 582
 583     if (!client->domain_name)
 584         client->domain_name = avahi_client_get_string_reply_and_block(client, "GetDomainName", NULL);
 585
 586     return client->domain_name;
 587 }
 588
 589 const char* avahi_client_get_host_name (AvahiClient *client) {
 590     assert(client);
 591
 592     if (client->state == AVAHI_CLIENT_DISCONNECTED) {
 593         avahi_client_set_errno(client, AVAHI_ERR_BAD_STATE);
 594         return NULL;
 595     }
 596
 597     if (!client->host_name)
 598         client->host_name = avahi_client_get_string_reply_and_block(client, "GetHostName", NULL);
 599
 600     return client->host_name;
 601 }
 602
 603 const char* avahi_client_get_host_name_fqdn (AvahiClient *client) {
 604     assert(client);
 605
 606     if (client->state == AVAHI_CLIENT_DISCONNECTED) {
 607         avahi_client_set_errno(client, AVAHI_ERR_BAD_STATE);
 608         return NULL;
 609     }
 610
 611     if (!client->host_name_fqdn)
 612         client->host_name_fqdn = avahi_client_get_string_reply_and_block(client, "GetHostNameFqdn", NULL);
 613
 614     return client->host_name_fqdn;
 615 }
 616
 617 AvahiClientState avahi_client_get_state(AvahiClient *client) {
 618     assert(client);
 619
 620     return client->state;
 621 }
 622
 623 int avahi_client_errno(AvahiClient *client) {
 624     assert(client);
 625
 626     return client->error;
 627 }
 628
 629 /* Just for internal use */
 630 int avahi_client_simple_method_call(AvahiClient *client, const char *path, const char *interface, const char *method) {
 631     DBusMessage *message = NULL, *reply = NULL;
 632     DBusError error;
 633     int r = AVAHI_OK;
 634
 635     dbus_error_init(&error);
 636
 637     assert(client);
 638     assert(path);
 639     assert(interface);
 640     assert(method);
 641
 642     if (!(message = dbus_message_new_method_call(AVAHI_DBUS_NAME, path, interface, method))) {
 643         r = avahi_client_set_errno(client, AVAHI_ERR_NO_MEMORY);
 644         goto fail;
 645     }
 646
 647     if (!(reply = dbus_connection_send_with_reply_and_block(client->bus, message, -1, &error)) ||
 648         dbus_error_is_set (&error)) {
 649         r = avahi_client_set_errno(client, AVAHI_ERR_DBUS_ERROR);
 650         goto fail;
 651     }
 652
 653     if (!dbus_message_get_args(reply, &error, DBUS_TYPE_INVALID) ||
 654         dbus_error_is_set (&error)) {
 655         r = avahi_client_set_errno(client, AVAHI_ERR_DBUS_ERROR);
 656         goto fail;
 657     }
 658
 659     dbus_message_unref(message);
 660     dbus_message_unref(reply);
 661
 662     return AVAHI_OK;
 663
 664 fail:
 665     if (dbus_error_is_set(&error)) {
 666         r = avahi_client_set_dbus_error(client, &error);
 667         dbus_error_free(&error);
 668     }
 669
 670     if (message)
 671         dbus_message_unref(message);
 672
 673     if (reply)
 674         dbus_message_unref(reply);
 675
 676     return r;
 677 }
 678
 679 uint32_t avahi_client_get_local_service_cookie(AvahiClient *client) {
 680     DBusMessage *message = NULL, *reply = NULL;
 681     DBusError error;
 682     assert(client);
 683
 684     if (client->state == AVAHI_CLIENT_DISCONNECTED) {
 685         avahi_client_set_errno(client, AVAHI_ERR_BAD_STATE);
 686         return AVAHI_SERVICE_COOKIE_INVALID;
 687     }
 688
 689     if (client->local_service_cookie_valid)
 690         return client->local_service_cookie;
 691
 692     dbus_error_init (&error);
 693
 694     if (!(message = dbus_message_new_method_call(AVAHI_DBUS_NAME, AVAHI_DBUS_PATH_SERVER, AVAHI_DBUS_INTERFACE_SERVER, "GetLocalServiceCookie"))) {
 695         avahi_client_set_errno(client, AVAHI_ERR_NO_MEMORY);
 696         goto fail;
 697     }
 698
 699     reply = dbus_connection_send_with_reply_and_block (client->bus, message, -1, &error);
 700
 701     if (!reply || dbus_error_is_set (&error))
 702         goto fail;
 703
 704     if (!dbus_message_get_args (reply, &error, DBUS_TYPE_UINT32, &client->local_service_cookie, DBUS_TYPE_INVALID) ||
 705         dbus_error_is_set (&error))
 706         goto fail;
 707
 708     dbus_message_unref(message);
 709     dbus_message_unref(reply);
 710
 711     client->local_service_cookie_valid = 1;
 712     return client->local_service_cookie;
 713
 714 fail:
 715
 716     if (message)
 717         dbus_message_unref(message);
 718     if (reply)
 719         dbus_message_unref(reply);
 720
 721     if (dbus_error_is_set(&error)) {
 722         avahi_client_set_dbus_error(client, &error);
 723         dbus_error_free(&error);
 724     }
 725
 726     return AVAHI_SERVICE_COOKIE_INVALID;
 727 }