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         case AVAHI_CLIENT_FAILURE:
  66             if (client->bus) {
  67                 dbus_connection_disconnect(client->bus);
  68                 dbus_connection_unref(client->bus);
  69                 client->bus = NULL;
  70             }
  71
  72             /* Fall through */
  73
  74         case AVAHI_CLIENT_S_COLLISION:
  75         case AVAHI_CLIENT_S_REGISTERING:
  76
  77             /* Clear cached strings */
  78             avahi_free(client->host_name);
  79             avahi_free(client->host_name_fqdn);
  80             avahi_free(client->domain_name);
  81
  82             client->host_name =  NULL;
  83             client->host_name_fqdn = NULL;
  84             client->domain_name = NULL;
  85             break;
  86
  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         char *e = NULL;
 143         int c;
 144
 145         if (!dbus_message_get_args(
 146                   message, &error,
 147                   DBUS_TYPE_INT32, &state,
 148                   DBUS_TYPE_STRING, &e,
 149                   DBUS_TYPE_INVALID) || dbus_error_is_set (&error)) {
 150             fprintf(stderr, "WARNING: Failed to parse Server.StateChanged signal: %s\n", error.message);
 151             goto fail;
 152         }
 153
 154         if ((c = avahi_error_dbus_to_number(e)) != AVAHI_OK)
 155             avahi_client_set_errno(client, c);
 156
 157         client_set_state(client, (AvahiClientState) state);
 158
 159     } else if (dbus_message_is_signal (message, AVAHI_DBUS_INTERFACE_ENTRY_GROUP, "StateChanged")) {
 160         const char *path;
 161         AvahiEntryGroup *g;
 162         path = dbus_message_get_path(message);
 163
 164         for (g = client->groups; g; g = g->groups_next)
 165             if (strcmp(g->path, path) == 0)
 166                 break;
 167
 168         if (g) {
 169             int32_t state;
 170             char *e;
 171             int c;
 172
 173             if (!dbus_message_get_args(
 174                       message, &error,
 175                       DBUS_TYPE_INT32, &state,
 176                       DBUS_TYPE_STRING, &e,
 177                       DBUS_TYPE_INVALID) ||
 178                 dbus_error_is_set(&error)) {
 179                 fprintf(stderr, "WARNING: Failed to parse EntryGroup.StateChanged signal: %s\n", error.message);
 180                 goto fail;
 181             }
 182
 183             if ((c = avahi_error_dbus_to_number(e)) != AVAHI_OK)
 184                 avahi_client_set_errno(client, c);
 185
 186             avahi_entry_group_set_state(g, state);
 187         }
 188
 189     } else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_DOMAIN_BROWSER, "ItemNew"))
 190         return avahi_domain_browser_event(client, AVAHI_BROWSER_NEW, message);
 191     else if (dbus_message_is_signal (message, AVAHI_DBUS_INTERFACE_DOMAIN_BROWSER, "ItemRemove"))
 192         return avahi_domain_browser_event(client, AVAHI_BROWSER_REMOVE, message);
 193     else if (dbus_message_is_signal (message, AVAHI_DBUS_INTERFACE_DOMAIN_BROWSER, "CacheExhausted"))
 194         return avahi_domain_browser_event(client, AVAHI_BROWSER_CACHE_EXHAUSTED, message);
 195     else if (dbus_message_is_signal (message, AVAHI_DBUS_INTERFACE_DOMAIN_BROWSER, "AllForNow"))
 196         return avahi_domain_browser_event(client, AVAHI_BROWSER_ALL_FOR_NOW, message);
 197     else if (dbus_message_is_signal (message, AVAHI_DBUS_INTERFACE_DOMAIN_BROWSER, "Failure"))
 198         return avahi_domain_browser_event(client, AVAHI_BROWSER_FAILURE, message);
 199
 200     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_SERVICE_TYPE_BROWSER, "ItemNew"))
 201         return avahi_service_type_browser_event (client, AVAHI_BROWSER_NEW, message);
 202     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_SERVICE_TYPE_BROWSER, "ItemRemove"))
 203         return avahi_service_type_browser_event (client, AVAHI_BROWSER_REMOVE, message);
 204     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_SERVICE_TYPE_BROWSER, "CacheExhausted"))
 205         return avahi_service_type_browser_event (client, AVAHI_BROWSER_CACHE_EXHAUSTED, message);
 206     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_SERVICE_TYPE_BROWSER, "AllForNow"))
 207         return avahi_service_type_browser_event (client, AVAHI_BROWSER_ALL_FOR_NOW, message);
 208     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_SERVICE_TYPE_BROWSER, "Failure"))
 209         return avahi_service_type_browser_event (client, AVAHI_BROWSER_FAILURE, message);
 210
 211     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_SERVICE_BROWSER, "ItemNew"))
 212         return avahi_service_browser_event (client, AVAHI_BROWSER_NEW, message);
 213     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_SERVICE_BROWSER, "ItemRemove"))
 214         return avahi_service_browser_event (client, AVAHI_BROWSER_REMOVE, message);
 215     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_SERVICE_BROWSER, "CacheExhausted"))
 216         return avahi_service_browser_event (client, AVAHI_BROWSER_CACHE_EXHAUSTED, message);
 217     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_SERVICE_BROWSER, "AllForNow"))
 218         return avahi_service_browser_event (client, AVAHI_BROWSER_ALL_FOR_NOW, message);
 219     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_SERVICE_BROWSER, "Failure"))
 220         return avahi_service_browser_event (client, AVAHI_BROWSER_FAILURE, message);
 221
 222     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_SERVICE_RESOLVER, "Found"))
 223         return avahi_service_resolver_event (client, AVAHI_RESOLVER_FOUND, message);
 224     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_SERVICE_RESOLVER, "Failure"))
 225         return avahi_service_resolver_event (client, AVAHI_RESOLVER_FAILURE, message);
 226
 227     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_HOST_NAME_RESOLVER, "Found"))
 228         return avahi_host_name_resolver_event (client, AVAHI_RESOLVER_FOUND, message);
 229     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_HOST_NAME_RESOLVER, "Failure"))
 230         return avahi_host_name_resolver_event (client, AVAHI_RESOLVER_FAILURE, message);
 231
 232     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_ADDRESS_RESOLVER, "Found"))
 233         return avahi_address_resolver_event (client, AVAHI_RESOLVER_FOUND, message);
 234     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_ADDRESS_RESOLVER, "Failure"))
 235         return avahi_address_resolver_event (client, AVAHI_RESOLVER_FAILURE, message);
 236
 237     return DBUS_HANDLER_RESULT_HANDLED;
 238
 239 fail:
 240
 241     dbus_error_free (&error);
 242     return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
 243 }
 244
 245 static int get_server_state(AvahiClient *client, int *ret_error) {
 246     DBusMessage *message = NULL, *reply = NULL;
 247     DBusError error;
 248     int32_t state;
 249     int e = AVAHI_ERR_NO_MEMORY;
 250
 251     assert(client);
 252
 253     dbus_error_init(&error);
 254
 255     if (!(message = dbus_message_new_method_call(AVAHI_DBUS_NAME, AVAHI_DBUS_PATH_SERVER, AVAHI_DBUS_INTERFACE_SERVER, "GetState")))
 256         goto fail;
 257
 258     reply = dbus_connection_send_with_reply_and_block (client->bus, message, -1, &error);
 259
 260     if (!reply || dbus_error_is_set (&error))
 261         goto fail;
 262
 263     if (!dbus_message_get_args(reply, &error, DBUS_TYPE_INT32, &state, DBUS_TYPE_INVALID) ||
 264         dbus_error_is_set (&error))
 265         goto fail;
 266
 267     client_set_state(client, (AvahiServerState) state);
 268
 269     dbus_message_unref(message);
 270     dbus_message_unref(reply);
 271
 272     return AVAHI_OK;
 273
 274 fail:
 275     if (dbus_error_is_set(&error)) {
 276         e = avahi_error_dbus_to_number (error.name);
 277         dbus_error_free(&error);
 278     }
 279
 280     if (ret_error)
 281         *ret_error = e;
 282
 283     if (message)
 284         dbus_message_unref(message);
 285     if (reply)
 286         dbus_message_unref(reply);
 287
 288     return e;
 289 }
 290
 291 static int check_version(AvahiClient *client, int *ret_error) {
 292     DBusMessage *message = NULL, *reply  = NULL;
 293     DBusError error;
 294     char *version;
 295     int e = AVAHI_ERR_NO_MEMORY;
 296
 297     assert(client);
 298
 299     dbus_error_init(&error);
 300
 301     if (!(message = dbus_message_new_method_call(AVAHI_DBUS_NAME, AVAHI_DBUS_PATH_SERVER, AVAHI_DBUS_INTERFACE_SERVER, "GetVersionString")))
 302         goto fail;
 303
 304     reply = dbus_connection_send_with_reply_and_block (client->bus, message, -1, &error);
 305
 306     if (!reply || dbus_error_is_set (&error))
 307         goto fail;
 308
 309     if (!dbus_message_get_args (reply, &error, DBUS_TYPE_STRING, &version, DBUS_TYPE_INVALID) ||
 310         dbus_error_is_set (&error))
 311         goto fail;
 312
 313     if (strcmp(version, PACKAGE_STRING) != 0) {
 314         e = AVAHI_ERR_VERSION_MISMATCH;
 315         goto fail;
 316     }
 317
 318     dbus_message_unref(message);
 319     dbus_message_unref(reply);
 320
 321     return AVAHI_OK;
 322
 323 fail:
 324     if (dbus_error_is_set(&error)) {
 325         e = avahi_error_dbus_to_number (error.name);
 326         dbus_error_free(&error);
 327     }
 328
 329     if (ret_error)
 330         *ret_error = e;
 331
 332     if (message)
 333         dbus_message_unref(message);
 334     if (reply)
 335         dbus_message_unref(reply);
 336
 337     return e;
 338 }
 339
 340
 341 /* This function acts like dbus_bus_get but creates a private
 342  * connection instead */
 343 static DBusConnection*
 344 avahi_dbus_bus_get (DBusError *error)
 345 {
 346     DBusConnection *conn;
 347     const char *env_addr;
 348
 349     env_addr = getenv ("DBUS_SYSTEM_BUS_ADDRESS");
 350
 351     if (env_addr == NULL || (*env_addr == 0))
 352     {
 353         env_addr = DBUS_SYSTEM_BUS_DEFAULT_ADDRESS;
 354     }
 355
 356     conn = dbus_connection_open_private (env_addr, error);
 357
 358     if (!conn)
 359         return NULL;
 360
 361     dbus_connection_set_exit_on_disconnect (conn, FALSE);
 362
 363     if (!dbus_bus_register (conn, error))
 364     {
 365         dbus_connection_close (conn);
 366         dbus_connection_unref (conn);
 367
 368         return NULL;
 369     }
 370
 371     return conn;
 372 }
 373
 374 AvahiClient *avahi_client_new(const AvahiPoll *poll_api, AvahiClientCallback callback, void *userdata, int *ret_error) {
 375     AvahiClient *client = NULL;
 376     DBusError error;
 377
 378     dbus_error_init (&error);
 379
 380     if (!(client = avahi_new(AvahiClient, 1))) {
 381         if (ret_error)
 382             *ret_error = AVAHI_ERR_NO_MEMORY;
 383         goto fail;
 384     }
 385
 386     client->poll_api = poll_api;
 387     client->error = AVAHI_OK;
 388     client->callback = callback;
 389     client->userdata = userdata;
 390     client->state = AVAHI_CLIENT_DISCONNECTED;
 391
 392     client->host_name = NULL;
 393     client->host_name_fqdn = NULL;
 394     client->domain_name = NULL;
 395     client->version_string = NULL;
 396     client->local_service_cookie_valid = 0;
 397
 398     AVAHI_LLIST_HEAD_INIT(AvahiEntryGroup, client->groups);
 399     AVAHI_LLIST_HEAD_INIT(AvahiDomainBrowser, client->domain_browsers);
 400     AVAHI_LLIST_HEAD_INIT(AvahiServiceBrowser, client->service_browsers);
 401     AVAHI_LLIST_HEAD_INIT(AvahiServiceTypeBrowser, client->service_type_browsers);
 402     AVAHI_LLIST_HEAD_INIT(AvahiServiceResolver, client->service_resolvers);
 403     AVAHI_LLIST_HEAD_INIT(AvahiHostNameResolver, client->host_name_resolvers);
 404     AVAHI_LLIST_HEAD_INIT(AvahiAddressResolver, client->address_resolvers);
 405
 406     if (!(client->bus = avahi_dbus_bus_get(&error)) ||
 407         dbus_error_is_set (&error))
 408         goto fail;
 409
 410     if (avahi_dbus_connection_glue(client->bus, poll_api) < 0) {
 411         if (ret_error)
 412             *ret_error = AVAHI_ERR_NO_MEMORY; /* Not optimal */
 413         goto fail;
 414     }
 415
 416     if (!dbus_connection_add_filter (client->bus, filter_func, client, NULL)) {
 417         if (ret_error)
 418             *ret_error = AVAHI_ERR_NO_MEMORY;
 419         goto fail;
 420     }
 421
 422     dbus_bus_add_match(
 423         client->bus,
 424         "type='signal', "
 425         "interface='" AVAHI_DBUS_INTERFACE_SERVER "', "
 426         "sender='" AVAHI_DBUS_NAME "', "
 427         "path='" AVAHI_DBUS_PATH_SERVER "'",
 428         &error);
 429
 430     if (dbus_error_is_set (&error))
 431         goto fail;
 432
 433     dbus_bus_add_match (
 434         client->bus,
 435         "type='signal', "
 436         "interface='" DBUS_INTERFACE_DBUS "', "
 437         "sender='" DBUS_SERVICE_DBUS "', "
 438         "path='" DBUS_PATH_DBUS "'",
 439         &error);
 440
 441     if (dbus_error_is_set (&error))
 442         goto fail;
 443
 444         dbus_bus_add_match (
 445         client->bus,
 446         "type='signal', "
 447         "interface='" DBUS_INTERFACE_LOCAL "'",
 448         &error);
 449
 450     if (dbus_error_is_set (&error))
 451         goto fail;
 452
 453     if (!(dbus_bus_name_has_owner(client->bus, AVAHI_DBUS_NAME, &error)) ||
 454         dbus_error_is_set(&error)) {
 455
 456         /* We free the error so its not set, that way the fail target
 457          * will return the NO_DAEMON error rather than a DBUS error */
 458         dbus_error_free (&error);
 459
 460         if (ret_error)
 461             *ret_error = AVAHI_ERR_NO_DAEMON;
 462
 463         goto fail;
 464     }
 465
 466     if (check_version(client, ret_error) < 0)
 467         goto fail;
 468
 469     if (get_server_state(client, ret_error) < 0)
 470         goto fail;
 471
 472     return client;
 473
 474 fail:
 475
 476     if (client)
 477         avahi_client_free(client);
 478
 479     if (dbus_error_is_set(&error)) {
 480
 481         if (ret_error)
 482             *ret_error = avahi_error_dbus_to_number(error.name);
 483
 484         dbus_error_free(&error);
 485     }
 486
 487     return NULL;
 488 }
 489
 490 void avahi_client_free(AvahiClient *client) {
 491     assert(client);
 492
 493     while (client->groups)
 494         avahi_entry_group_free(client->groups);
 495
 496     while (client->domain_browsers)
 497         avahi_domain_browser_free(client->domain_browsers);
 498
 499     while (client->service_browsers)
 500         avahi_service_browser_free(client->service_browsers);
 501
 502     while (client->service_type_browsers)
 503         avahi_service_type_browser_free(client->service_type_browsers);
 504
 505     while (client->service_resolvers)
 506         avahi_service_resolver_free(client->service_resolvers);
 507
 508     if (client->bus) {
 509         dbus_connection_disconnect(client->bus);
 510         dbus_connection_unref(client->bus);
 511     }
 512
 513     avahi_free(client->version_string);
 514     avahi_free(client->host_name);
 515     avahi_free(client->host_name_fqdn);
 516     avahi_free(client->domain_name);
 517
 518     avahi_free(client);
 519 }
 520
 521 static char* avahi_client_get_string_reply_and_block (AvahiClient *client, const char *method, const char *param) {
 522     DBusMessage *message = NULL, *reply = NULL;
 523     DBusError error;
 524     char *ret, *n;
 525
 526     assert(client);
 527     assert(method);
 528
 529     dbus_error_init (&error);
 530
 531     if (!(message = dbus_message_new_method_call (AVAHI_DBUS_NAME, AVAHI_DBUS_PATH_SERVER, AVAHI_DBUS_INTERFACE_SERVER, method))) {
 532         avahi_client_set_errno(client, AVAHI_ERR_NO_MEMORY);
 533         goto fail;
 534     }
 535
 536     if (param) {
 537         if (!dbus_message_append_args (message, DBUS_TYPE_STRING, &param, DBUS_TYPE_INVALID)) {
 538             avahi_client_set_errno (client, AVAHI_ERR_NO_MEMORY);
 539             goto fail;
 540         }
 541     }
 542
 543     reply = dbus_connection_send_with_reply_and_block (client->bus, message, -1, &error);
 544
 545     if (!reply || dbus_error_is_set (&error))
 546         goto fail;
 547
 548     if (!dbus_message_get_args (reply, &error, DBUS_TYPE_STRING, &ret, DBUS_TYPE_INVALID) ||
 549         dbus_error_is_set (&error))
 550         goto fail;
 551
 552     if (!(n = avahi_strdup(ret))) {
 553         avahi_client_set_errno(client, AVAHI_ERR_NO_MEMORY);
 554         goto fail;
 555     }
 556
 557     dbus_message_unref(message);
 558     dbus_message_unref(reply);
 559
 560     return n;
 561
 562 fail:
 563
 564     if (message)
 565         dbus_message_unref(message);
 566     if (reply)
 567         dbus_message_unref(reply);
 568
 569     if (dbus_error_is_set(&error)) {
 570         avahi_client_set_dbus_error(client, &error);
 571         dbus_error_free(&error);
 572     }
 573
 574     return NULL;
 575 }
 576
 577 const char* avahi_client_get_version_string (AvahiClient *client) {
 578     assert(client);
 579
 580     if (client->state == AVAHI_CLIENT_DISCONNECTED) {
 581         avahi_client_set_errno(client, AVAHI_ERR_BAD_STATE);
 582         return NULL;
 583     }
 584
 585     if (!client->version_string)
 586         client->version_string = avahi_client_get_string_reply_and_block(client, "GetVersionString", NULL);
 587
 588     return client->version_string;
 589 }
 590
 591 const char* avahi_client_get_domain_name (AvahiClient *client) {
 592     assert(client);
 593
 594     if (client->state == AVAHI_CLIENT_DISCONNECTED) {
 595         avahi_client_set_errno(client, AVAHI_ERR_BAD_STATE);
 596         return NULL;
 597     }
 598
 599     if (!client->domain_name)
 600         client->domain_name = avahi_client_get_string_reply_and_block(client, "GetDomainName", NULL);
 601
 602     return client->domain_name;
 603 }
 604
 605 const char* avahi_client_get_host_name (AvahiClient *client) {
 606     assert(client);
 607
 608     if (client->state == AVAHI_CLIENT_DISCONNECTED) {
 609         avahi_client_set_errno(client, AVAHI_ERR_BAD_STATE);
 610         return NULL;
 611     }
 612
 613     if (!client->host_name)
 614         client->host_name = avahi_client_get_string_reply_and_block(client, "GetHostName", NULL);
 615
 616     return client->host_name;
 617 }
 618
 619 const char* avahi_client_get_host_name_fqdn (AvahiClient *client) {
 620     assert(client);
 621
 622     if (client->state == AVAHI_CLIENT_DISCONNECTED) {
 623         avahi_client_set_errno(client, AVAHI_ERR_BAD_STATE);
 624         return NULL;
 625     }
 626
 627     if (!client->host_name_fqdn)
 628         client->host_name_fqdn = avahi_client_get_string_reply_and_block(client, "GetHostNameFqdn", NULL);
 629
 630     return client->host_name_fqdn;
 631 }
 632
 633 AvahiClientState avahi_client_get_state(AvahiClient *client) {
 634     assert(client);
 635
 636     return client->state;
 637 }
 638
 639 int avahi_client_errno(AvahiClient *client) {
 640     assert(client);
 641
 642     return client->error;
 643 }
 644
 645 /* Just for internal use */
 646 int avahi_client_simple_method_call(AvahiClient *client, const char *path, const char *interface, const char *method) {
 647     DBusMessage *message = NULL, *reply = NULL;
 648     DBusError error;
 649     int r = AVAHI_OK;
 650
 651     dbus_error_init(&error);
 652
 653     assert(client);
 654     assert(path);
 655     assert(interface);
 656     assert(method);
 657
 658     if (!(message = dbus_message_new_method_call(AVAHI_DBUS_NAME, path, interface, method))) {
 659         r = avahi_client_set_errno(client, AVAHI_ERR_NO_MEMORY);
 660         goto fail;
 661     }
 662
 663     if (!(reply = dbus_connection_send_with_reply_and_block(client->bus, message, -1, &error)) ||
 664         dbus_error_is_set (&error)) {
 665         r = avahi_client_set_errno(client, AVAHI_ERR_DBUS_ERROR);
 666         goto fail;
 667     }
 668
 669     if (!dbus_message_get_args(reply, &error, DBUS_TYPE_INVALID) ||
 670         dbus_error_is_set (&error)) {
 671         r = avahi_client_set_errno(client, AVAHI_ERR_DBUS_ERROR);
 672         goto fail;
 673     }
 674
 675     dbus_message_unref(message);
 676     dbus_message_unref(reply);
 677
 678     return AVAHI_OK;
 679
 680 fail:
 681     if (dbus_error_is_set(&error)) {
 682         r = avahi_client_set_dbus_error(client, &error);
 683         dbus_error_free(&error);
 684     }
 685
 686     if (message)
 687         dbus_message_unref(message);
 688
 689     if (reply)
 690         dbus_message_unref(reply);
 691
 692     return r;
 693 }
 694
 695 uint32_t avahi_client_get_local_service_cookie(AvahiClient *client) {
 696     DBusMessage *message = NULL, *reply = NULL;
 697     DBusError error;
 698     assert(client);
 699
 700     if (client->state == AVAHI_CLIENT_DISCONNECTED) {
 701         avahi_client_set_errno(client, AVAHI_ERR_BAD_STATE);
 702         return AVAHI_SERVICE_COOKIE_INVALID;
 703     }
 704
 705     if (client->local_service_cookie_valid)
 706         return client->local_service_cookie;
 707
 708     dbus_error_init (&error);
 709
 710     if (!(message = dbus_message_new_method_call(AVAHI_DBUS_NAME, AVAHI_DBUS_PATH_SERVER, AVAHI_DBUS_INTERFACE_SERVER, "GetLocalServiceCookie"))) {
 711         avahi_client_set_errno(client, AVAHI_ERR_NO_MEMORY);
 712         goto fail;
 713     }
 714
 715     reply = dbus_connection_send_with_reply_and_block (client->bus, message, -1, &error);
 716
 717     if (!reply || dbus_error_is_set (&error))
 718         goto fail;
 719
 720     if (!dbus_message_get_args (reply, &error, DBUS_TYPE_UINT32, &client->local_service_cookie, DBUS_TYPE_INVALID) ||
 721         dbus_error_is_set (&error))
 722         goto fail;
 723
 724     dbus_message_unref(message);
 725     dbus_message_unref(reply);
 726
 727     client->local_service_cookie_valid = 1;
 728     return client->local_service_cookie;
 729
 730 fail:
 731
 732     if (message)
 733         dbus_message_unref(message);
 734     if (reply)
 735         dbus_message_unref(reply);
 736
 737     if (dbus_error_is_set(&error)) {
 738         avahi_client_set_dbus_error(client, &error);
 739         dbus_error_free(&error);
 740     }
 741
 742     return AVAHI_SERVICE_COOKIE_INVALID;
 743 }