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_RUNNING:
  87             break;
  88
  89     }
  90
  91     if (client->callback)
  92         client->callback (client, state, client->userdata);
  93 }
  94
  95 static DBusHandlerResult filter_func(DBusConnection *bus, DBusMessage *message, void *userdata) {
  96     AvahiClient *client = userdata;
  97     DBusError error;
  98
  99     assert(bus);
 100     assert(message);
 101
 102     dbus_error_init (&error);
 103
 104 /*     fprintf(stderr, "dbus: interface=%s, path=%s, member=%s\n", */
 105 /*             dbus_message_get_interface (message), */
 106 /*             dbus_message_get_path (message), */
 107 /*             dbus_message_get_member (message)); */
 108
 109     if (client->state == AVAHI_CLIENT_DISCONNECTED)
 110         goto fail;
 111
 112     if (dbus_message_is_signal(message, DBUS_INTERFACE_LOCAL, "Disconnected")) {
 113
 114         /* The DBUS server died or kicked us */
 115         client_set_state(client, AVAHI_CLIENT_DISCONNECTED);
 116
 117     } if (dbus_message_is_signal(message, DBUS_INTERFACE_DBUS, "NameOwnerChanged")) {
 118         char *name, *old, *new;
 119
 120         if (!dbus_message_get_args(
 121                   message, &error,
 122                   DBUS_TYPE_STRING, &name,
 123                   DBUS_TYPE_STRING, &old,
 124                   DBUS_TYPE_STRING, &new,
 125                   DBUS_TYPE_INVALID) || dbus_error_is_set (&error)) {
 126
 127             fprintf(stderr, "WARNING: Failed to parse NameOwnerChanged signal: %s\n", error.message);
 128             goto fail;
 129         }
 130
 131         if (strcmp(name, AVAHI_DBUS_NAME) == 0)
 132
 133             /* Regardless if the server lost or acquired its name or
 134              * if the name was transfered: our services are no longer
 135              * available, so we disconnect ourselves */
 136
 137             client_set_state(client, AVAHI_CLIENT_DISCONNECTED);
 138
 139     } else if (dbus_message_is_signal (message, AVAHI_DBUS_INTERFACE_SERVER, "StateChanged")) {
 140         int32_t state;
 141         char *e = NULL;
 142         int c;
 143
 144         if (!dbus_message_get_args(
 145                   message, &error,
 146                   DBUS_TYPE_INT32, &state,
 147                   DBUS_TYPE_STRING, &e,
 148                   DBUS_TYPE_INVALID) || dbus_error_is_set (&error)) {
 149             fprintf(stderr, "WARNING: Failed to parse Server.StateChanged signal: %s\n", error.message);
 150             goto fail;
 151         }
 152
 153         if ((c = avahi_error_dbus_to_number(e)) != AVAHI_OK)
 154             avahi_client_set_errno(client, c);
 155
 156         client_set_state(client, (AvahiClientState) state);
 157
 158     } else if (dbus_message_is_signal (message, AVAHI_DBUS_INTERFACE_ENTRY_GROUP, "StateChanged")) {
 159         const char *path;
 160         AvahiEntryGroup *g;
 161         path = dbus_message_get_path(message);
 162
 163         for (g = client->groups; g; g = g->groups_next)
 164             if (strcmp(g->path, path) == 0)
 165                 break;
 166
 167         if (g) {
 168             int32_t state;
 169             char *e;
 170             int c;
 171
 172             if (!dbus_message_get_args(
 173                       message, &error,
 174                       DBUS_TYPE_INT32, &state,
 175                       DBUS_TYPE_STRING, &e,
 176                       DBUS_TYPE_INVALID) ||
 177                 dbus_error_is_set(&error)) {
 178                 fprintf(stderr, "WARNING: Failed to parse EntryGroup.StateChanged signal: %s\n", error.message);
 179                 goto fail;
 180             }
 181
 182             if ((c = avahi_error_dbus_to_number(e)) != AVAHI_OK)
 183                 avahi_client_set_errno(client, c);
 184
 185             avahi_entry_group_set_state(g, state);
 186         }
 187
 188     } else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_DOMAIN_BROWSER, "ItemNew"))
 189         return avahi_domain_browser_event(client, AVAHI_BROWSER_NEW, message);
 190     else if (dbus_message_is_signal (message, AVAHI_DBUS_INTERFACE_DOMAIN_BROWSER, "ItemRemove"))
 191         return avahi_domain_browser_event(client, AVAHI_BROWSER_REMOVE, message);
 192     else if (dbus_message_is_signal (message, AVAHI_DBUS_INTERFACE_DOMAIN_BROWSER, "CacheExhausted"))
 193         return avahi_domain_browser_event(client, AVAHI_BROWSER_CACHE_EXHAUSTED, message);
 194     else if (dbus_message_is_signal (message, AVAHI_DBUS_INTERFACE_DOMAIN_BROWSER, "AllForNow"))
 195         return avahi_domain_browser_event(client, AVAHI_BROWSER_ALL_FOR_NOW, message);
 196     else if (dbus_message_is_signal (message, AVAHI_DBUS_INTERFACE_DOMAIN_BROWSER, "Failure"))
 197         return avahi_domain_browser_event(client, AVAHI_BROWSER_FAILURE, message);
 198
 199     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_SERVICE_TYPE_BROWSER, "ItemNew"))
 200         return avahi_service_type_browser_event (client, AVAHI_BROWSER_NEW, message);
 201     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_SERVICE_TYPE_BROWSER, "ItemRemove"))
 202         return avahi_service_type_browser_event (client, AVAHI_BROWSER_REMOVE, message);
 203     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_SERVICE_TYPE_BROWSER, "CacheExhausted"))
 204         return avahi_service_type_browser_event (client, AVAHI_BROWSER_CACHE_EXHAUSTED, message);
 205     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_SERVICE_TYPE_BROWSER, "AllForNow"))
 206         return avahi_service_type_browser_event (client, AVAHI_BROWSER_ALL_FOR_NOW, message);
 207     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_SERVICE_TYPE_BROWSER, "Failure"))
 208         return avahi_service_type_browser_event (client, AVAHI_BROWSER_FAILURE, message);
 209
 210     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_SERVICE_BROWSER, "ItemNew"))
 211         return avahi_service_browser_event (client, AVAHI_BROWSER_NEW, message);
 212     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_SERVICE_BROWSER, "ItemRemove"))
 213         return avahi_service_browser_event (client, AVAHI_BROWSER_REMOVE, message);
 214     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_SERVICE_BROWSER, "CacheExhausted"))
 215         return avahi_service_browser_event (client, AVAHI_BROWSER_CACHE_EXHAUSTED, message);
 216     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_SERVICE_BROWSER, "AllForNow"))
 217         return avahi_service_browser_event (client, AVAHI_BROWSER_ALL_FOR_NOW, message);
 218     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_SERVICE_BROWSER, "Failure"))
 219         return avahi_service_browser_event (client, AVAHI_BROWSER_FAILURE, message);
 220
 221     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_SERVICE_RESOLVER, "Found"))
 222         return avahi_service_resolver_event (client, AVAHI_RESOLVER_FOUND, message);
 223     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_SERVICE_RESOLVER, "Failure"))
 224         return avahi_service_resolver_event (client, AVAHI_RESOLVER_FAILURE, message);
 225
 226     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_HOST_NAME_RESOLVER, "Found"))
 227         return avahi_host_name_resolver_event (client, AVAHI_RESOLVER_FOUND, message);
 228     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_HOST_NAME_RESOLVER, "Failure"))
 229         return avahi_host_name_resolver_event (client, AVAHI_RESOLVER_FAILURE, message);
 230
 231     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_ADDRESS_RESOLVER, "Found"))
 232         return avahi_address_resolver_event (client, AVAHI_RESOLVER_FOUND, message);
 233     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_ADDRESS_RESOLVER, "Failure"))
 234         return avahi_address_resolver_event (client, AVAHI_RESOLVER_FAILURE, message);
 235
 236     return DBUS_HANDLER_RESULT_HANDLED;
 237
 238 fail:
 239
 240     dbus_error_free (&error);
 241     return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
 242 }
 243
 244 static int get_server_state(AvahiClient *client, int *ret_error) {
 245     DBusMessage *message = NULL, *reply = NULL;
 246     DBusError error;
 247     int32_t state;
 248     int e = AVAHI_ERR_NO_MEMORY;
 249
 250     assert(client);
 251
 252     dbus_error_init(&error);
 253
 254     if (!(message = dbus_message_new_method_call(AVAHI_DBUS_NAME, AVAHI_DBUS_PATH_SERVER, AVAHI_DBUS_INTERFACE_SERVER, "GetState")))
 255         goto fail;
 256
 257     reply = dbus_connection_send_with_reply_and_block (client->bus, message, -1, &error);
 258
 259     if (!reply || dbus_error_is_set (&error))
 260         goto fail;
 261
 262     if (!dbus_message_get_args(reply, &error, DBUS_TYPE_INT32, &state, DBUS_TYPE_INVALID) ||
 263         dbus_error_is_set (&error))
 264         goto fail;
 265
 266     client_set_state(client, (AvahiServerState) state);
 267
 268     dbus_message_unref(message);
 269     dbus_message_unref(reply);
 270
 271     return AVAHI_OK;
 272
 273 fail:
 274     if (dbus_error_is_set(&error)) {
 275         e = avahi_error_dbus_to_number (error.name);
 276         dbus_error_free(&error);
 277     }
 278
 279     if (ret_error)
 280         *ret_error = e;
 281
 282     if (message)
 283         dbus_message_unref(message);
 284     if (reply)
 285         dbus_message_unref(reply);
 286
 287     return e;
 288 }
 289
 290 static int check_version(AvahiClient *client, int *ret_error) {
 291     DBusMessage *message = NULL, *reply  = NULL;
 292     DBusError error;
 293     char *version;
 294     int e = AVAHI_ERR_NO_MEMORY;
 295
 296     assert(client);
 297
 298     dbus_error_init(&error);
 299
 300     if (!(message = dbus_message_new_method_call(AVAHI_DBUS_NAME, AVAHI_DBUS_PATH_SERVER, AVAHI_DBUS_INTERFACE_SERVER, "GetVersionString")))
 301         goto fail;
 302
 303     reply = dbus_connection_send_with_reply_and_block (client->bus, message, -1, &error);
 304
 305     if (!reply || dbus_error_is_set (&error))
 306         goto fail;
 307
 308     if (!dbus_message_get_args (reply, &error, DBUS_TYPE_STRING, &version, DBUS_TYPE_INVALID) ||
 309         dbus_error_is_set (&error))
 310         goto fail;
 311
 312     if (strcmp(version, PACKAGE_STRING) != 0) {
 313         e = AVAHI_ERR_VERSION_MISMATCH;
 314         goto fail;
 315     }
 316
 317     dbus_message_unref(message);
 318     dbus_message_unref(reply);
 319
 320     return AVAHI_OK;
 321
 322 fail:
 323     if (dbus_error_is_set(&error)) {
 324         e = avahi_error_dbus_to_number (error.name);
 325         dbus_error_free(&error);
 326     }
 327
 328     if (ret_error)
 329         *ret_error = e;
 330
 331     if (message)
 332         dbus_message_unref(message);
 333     if (reply)
 334         dbus_message_unref(reply);
 335
 336     return e;
 337 }
 338
 339
 340 /* This function acts like dbus_bus_get but creates a private
 341  * connection instead */
 342 static DBusConnection*
 343 avahi_dbus_bus_get (DBusError *error)
 344 {
 345     DBusConnection *conn;
 346     const char *env_addr;
 347
 348     env_addr = getenv ("DBUS_SYSTEM_BUS_ADDRESS");
 349
 350     if (env_addr == NULL || (*env_addr == 0))
 351     {
 352         env_addr = DBUS_SYSTEM_BUS_DEFAULT_ADDRESS;
 353     }
 354
 355     conn = dbus_connection_open_private (env_addr, error);
 356
 357     if (!conn)
 358         return NULL;
 359
 360     dbus_connection_set_exit_on_disconnect (conn, FALSE);
 361
 362     if (!dbus_bus_register (conn, error))
 363     {
 364         dbus_connection_close (conn);
 365         dbus_connection_unref (conn);
 366
 367         return NULL;
 368     }
 369
 370     return conn;
 371 }
 372
 373 AvahiClient *avahi_client_new(const AvahiPoll *poll_api, AvahiClientCallback callback, void *userdata, int *ret_error) {
 374     AvahiClient *client = NULL;
 375     DBusError error;
 376
 377     dbus_error_init (&error);
 378
 379     if (!(client = avahi_new(AvahiClient, 1))) {
 380         if (ret_error)
 381             *ret_error = AVAHI_ERR_NO_MEMORY;
 382         goto fail;
 383     }
 384
 385     client->poll_api = poll_api;
 386     client->error = AVAHI_OK;
 387     client->callback = callback;
 388     client->userdata = userdata;
 389     client->state = AVAHI_CLIENT_DISCONNECTED;
 390
 391     client->host_name = NULL;
 392     client->host_name_fqdn = NULL;
 393     client->domain_name = NULL;
 394     client->version_string = NULL;
 395     client->local_service_cookie_valid = 0;
 396
 397     AVAHI_LLIST_HEAD_INIT(AvahiEntryGroup, client->groups);
 398     AVAHI_LLIST_HEAD_INIT(AvahiDomainBrowser, client->domain_browsers);
 399     AVAHI_LLIST_HEAD_INIT(AvahiServiceBrowser, client->service_browsers);
 400     AVAHI_LLIST_HEAD_INIT(AvahiServiceTypeBrowser, client->service_type_browsers);
 401     AVAHI_LLIST_HEAD_INIT(AvahiServiceResolver, client->service_resolvers);
 402     AVAHI_LLIST_HEAD_INIT(AvahiHostNameResolver, client->host_name_resolvers);
 403     AVAHI_LLIST_HEAD_INIT(AvahiAddressResolver, client->address_resolvers);
 404
 405     if (!(client->bus = avahi_dbus_bus_get(&error)) ||
 406         dbus_error_is_set (&error))
 407         goto fail;
 408
 409     if (avahi_dbus_connection_glue(client->bus, poll_api) < 0) {
 410         if (ret_error)
 411             *ret_error = AVAHI_ERR_NO_MEMORY; /* Not optimal */
 412         goto fail;
 413     }
 414
 415     if (!dbus_connection_add_filter (client->bus, filter_func, client, NULL)) {
 416         if (ret_error)
 417             *ret_error = AVAHI_ERR_NO_MEMORY;
 418         goto fail;
 419     }
 420
 421     dbus_bus_add_match(
 422         client->bus,
 423         "type='signal', "
 424         "interface='" AVAHI_DBUS_INTERFACE_SERVER "', "
 425         "sender='" AVAHI_DBUS_NAME "', "
 426         "path='" AVAHI_DBUS_PATH_SERVER "'",
 427         &error);
 428
 429     if (dbus_error_is_set (&error))
 430         goto fail;
 431
 432     dbus_bus_add_match (
 433         client->bus,
 434         "type='signal', "
 435         "interface='" DBUS_INTERFACE_DBUS "', "
 436         "sender='" DBUS_SERVICE_DBUS "', "
 437         "path='" DBUS_PATH_DBUS "'",
 438         &error);
 439
 440     if (dbus_error_is_set (&error))
 441         goto fail;
 442
 443         dbus_bus_add_match (
 444         client->bus,
 445         "type='signal', "
 446         "interface='" DBUS_INTERFACE_LOCAL "'",
 447         &error);
 448
 449     if (dbus_error_is_set (&error))
 450         goto fail;
 451
 452     if (!(dbus_bus_name_has_owner(client->bus, AVAHI_DBUS_NAME, &error)) ||
 453         dbus_error_is_set(&error)) {
 454
 455         /* We free the error so its not set, that way the fail target
 456          * will return the NO_DAEMON error rather than a DBUS error */
 457         dbus_error_free (&error);
 458
 459         if (ret_error)
 460             *ret_error = AVAHI_ERR_NO_DAEMON;
 461
 462         goto fail;
 463     }
 464
 465     if (check_version(client, ret_error) < 0)
 466         goto fail;
 467
 468     if (get_server_state(client, ret_error) < 0)
 469         goto fail;
 470
 471     return client;
 472
 473 fail:
 474
 475     if (client)
 476         avahi_client_free(client);
 477
 478     if (dbus_error_is_set(&error)) {
 479
 480         if (ret_error)
 481             *ret_error = avahi_error_dbus_to_number(error.name);
 482
 483         dbus_error_free(&error);
 484     }
 485
 486     return NULL;
 487 }
 488
 489 void avahi_client_free(AvahiClient *client) {
 490     assert(client);
 491
 492     while (client->groups)
 493         avahi_entry_group_free(client->groups);
 494
 495     while (client->domain_browsers)
 496         avahi_domain_browser_free(client->domain_browsers);
 497
 498     while (client->service_browsers)
 499         avahi_service_browser_free(client->service_browsers);
 500
 501     while (client->service_type_browsers)
 502         avahi_service_type_browser_free(client->service_type_browsers);
 503
 504     while (client->service_resolvers)
 505         avahi_service_resolver_free(client->service_resolvers);
 506
 507     if (client->bus) {
 508         dbus_connection_disconnect(client->bus);
 509         dbus_connection_unref(client->bus);
 510     }
 511
 512     avahi_free(client->version_string);
 513     avahi_free(client->host_name);
 514     avahi_free(client->host_name_fqdn);
 515     avahi_free(client->domain_name);
 516
 517     avahi_free(client);
 518 }
 519
 520 static char* avahi_client_get_string_reply_and_block (AvahiClient *client, const char *method, const char *param) {
 521     DBusMessage *message = NULL, *reply = NULL;
 522     DBusError error;
 523     char *ret, *n;
 524
 525     assert(client);
 526     assert(method);
 527
 528     dbus_error_init (&error);
 529
 530     if (!(message = dbus_message_new_method_call (AVAHI_DBUS_NAME, AVAHI_DBUS_PATH_SERVER, AVAHI_DBUS_INTERFACE_SERVER, method))) {
 531         avahi_client_set_errno(client, AVAHI_ERR_NO_MEMORY);
 532         goto fail;
 533     }
 534
 535     if (param) {
 536         if (!dbus_message_append_args (message, DBUS_TYPE_STRING, &param, DBUS_TYPE_INVALID)) {
 537             avahi_client_set_errno (client, AVAHI_ERR_NO_MEMORY);
 538             goto fail;
 539         }
 540     }
 541
 542     reply = dbus_connection_send_with_reply_and_block (client->bus, message, -1, &error);
 543
 544     if (!reply || dbus_error_is_set (&error))
 545         goto fail;
 546
 547     if (!dbus_message_get_args (reply, &error, DBUS_TYPE_STRING, &ret, DBUS_TYPE_INVALID) ||
 548         dbus_error_is_set (&error))
 549         goto fail;
 550
 551     if (!(n = avahi_strdup(ret))) {
 552         avahi_client_set_errno(client, AVAHI_ERR_NO_MEMORY);
 553         goto fail;
 554     }
 555
 556     dbus_message_unref(message);
 557     dbus_message_unref(reply);
 558
 559     return n;
 560
 561 fail:
 562
 563     if (message)
 564         dbus_message_unref(message);
 565     if (reply)
 566         dbus_message_unref(reply);
 567
 568     if (dbus_error_is_set(&error)) {
 569         avahi_client_set_dbus_error(client, &error);
 570         dbus_error_free(&error);
 571     }
 572
 573     return NULL;
 574 }
 575
 576 const char* avahi_client_get_version_string (AvahiClient *client) {
 577     assert(client);
 578
 579     if (client->state == AVAHI_CLIENT_DISCONNECTED) {
 580         avahi_client_set_errno(client, AVAHI_ERR_BAD_STATE);
 581         return NULL;
 582     }
 583
 584     if (!client->version_string)
 585         client->version_string = avahi_client_get_string_reply_and_block(client, "GetVersionString", NULL);
 586
 587     return client->version_string;
 588 }
 589
 590 const char* avahi_client_get_domain_name (AvahiClient *client) {
 591     assert(client);
 592
 593     if (client->state == AVAHI_CLIENT_DISCONNECTED) {
 594         avahi_client_set_errno(client, AVAHI_ERR_BAD_STATE);
 595         return NULL;
 596     }
 597
 598     if (!client->domain_name)
 599         client->domain_name = avahi_client_get_string_reply_and_block(client, "GetDomainName", NULL);
 600
 601     return client->domain_name;
 602 }
 603
 604 const char* avahi_client_get_host_name (AvahiClient *client) {
 605     assert(client);
 606
 607     if (client->state == AVAHI_CLIENT_DISCONNECTED) {
 608         avahi_client_set_errno(client, AVAHI_ERR_BAD_STATE);
 609         return NULL;
 610     }
 611
 612     if (!client->host_name)
 613         client->host_name = avahi_client_get_string_reply_and_block(client, "GetHostName", NULL);
 614
 615     return client->host_name;
 616 }
 617
 618 const char* avahi_client_get_host_name_fqdn (AvahiClient *client) {
 619     assert(client);
 620
 621     if (client->state == AVAHI_CLIENT_DISCONNECTED) {
 622         avahi_client_set_errno(client, AVAHI_ERR_BAD_STATE);
 623         return NULL;
 624     }
 625
 626     if (!client->host_name_fqdn)
 627         client->host_name_fqdn = avahi_client_get_string_reply_and_block(client, "GetHostNameFqdn", NULL);
 628
 629     return client->host_name_fqdn;
 630 }
 631
 632 AvahiClientState avahi_client_get_state(AvahiClient *client) {
 633     assert(client);
 634
 635     return client->state;
 636 }
 637
 638 int avahi_client_errno(AvahiClient *client) {
 639     assert(client);
 640
 641     return client->error;
 642 }
 643
 644 /* Just for internal use */
 645 int avahi_client_simple_method_call(AvahiClient *client, const char *path, const char *interface, const char *method) {
 646     DBusMessage *message = NULL, *reply = NULL;
 647     DBusError error;
 648     int r = AVAHI_OK;
 649
 650     dbus_error_init(&error);
 651
 652     assert(client);
 653     assert(path);
 654     assert(interface);
 655     assert(method);
 656
 657     if (!(message = dbus_message_new_method_call(AVAHI_DBUS_NAME, path, interface, method))) {
 658         r = avahi_client_set_errno(client, AVAHI_ERR_NO_MEMORY);
 659         goto fail;
 660     }
 661
 662     if (!(reply = dbus_connection_send_with_reply_and_block(client->bus, message, -1, &error)) ||
 663         dbus_error_is_set (&error)) {
 664         r = avahi_client_set_errno(client, AVAHI_ERR_DBUS_ERROR);
 665         goto fail;
 666     }
 667
 668     if (!dbus_message_get_args(reply, &error, DBUS_TYPE_INVALID) ||
 669         dbus_error_is_set (&error)) {
 670         r = avahi_client_set_errno(client, AVAHI_ERR_DBUS_ERROR);
 671         goto fail;
 672     }
 673
 674     dbus_message_unref(message);
 675     dbus_message_unref(reply);
 676
 677     return AVAHI_OK;
 678
 679 fail:
 680     if (dbus_error_is_set(&error)) {
 681         r = avahi_client_set_dbus_error(client, &error);
 682         dbus_error_free(&error);
 683     }
 684
 685     if (message)
 686         dbus_message_unref(message);
 687
 688     if (reply)
 689         dbus_message_unref(reply);
 690
 691     return r;
 692 }
 693
 694 uint32_t avahi_client_get_local_service_cookie(AvahiClient *client) {
 695     DBusMessage *message = NULL, *reply = NULL;
 696     DBusError error;
 697     assert(client);
 698
 699     if (client->state == AVAHI_CLIENT_DISCONNECTED) {
 700         avahi_client_set_errno(client, AVAHI_ERR_BAD_STATE);
 701         return AVAHI_SERVICE_COOKIE_INVALID;
 702     }
 703
 704     if (client->local_service_cookie_valid)
 705         return client->local_service_cookie;
 706
 707     dbus_error_init (&error);
 708
 709     if (!(message = dbus_message_new_method_call(AVAHI_DBUS_NAME, AVAHI_DBUS_PATH_SERVER, AVAHI_DBUS_INTERFACE_SERVER, "GetLocalServiceCookie"))) {
 710         avahi_client_set_errno(client, AVAHI_ERR_NO_MEMORY);
 711         goto fail;
 712     }
 713
 714     reply = dbus_connection_send_with_reply_and_block (client->bus, message, -1, &error);
 715
 716     if (!reply || dbus_error_is_set (&error))
 717         goto fail;
 718
 719     if (!dbus_message_get_args (reply, &error, DBUS_TYPE_UINT32, &client->local_service_cookie, DBUS_TYPE_INVALID) ||
 720         dbus_error_is_set (&error))
 721         goto fail;
 722
 723     dbus_message_unref(message);
 724     dbus_message_unref(reply);
 725
 726     client->local_service_cookie_valid = 1;
 727     return client->local_service_cookie;
 728
 729 fail:
 730
 731     if (message)
 732         dbus_message_unref(message);
 733     if (reply)
 734         dbus_message_unref(reply);
 735
 736     if (dbus_error_is_set(&error)) {
 737         avahi_client_set_dbus_error(client, &error);
 738         dbus_error_free(&error);
 739     }
 740
 741     return AVAHI_SERVICE_COOKIE_INVALID;
 742 }