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

   1 /***
   2   This file is part of avahi.
   3
   4   avahi is free software; you can redistribute it and/or modify it
   5   under the terms of the GNU Lesser General Public License as
   6   published by the Free Software Foundation; either version 2.1 of the
   7   License, or (at your option) any later version.
   8
   9   avahi is distributed in the hope that it will be useful, but WITHOUT
  10   ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  11   or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General
  12   Public License for more details.
  13
  14   You should have received a copy of the GNU Lesser General Public
  15   License along with avahi; if not, write to the Free Software
  16   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  17   USA.
  18 ***/
  19
  20 #ifdef HAVE_CONFIG_H
  21 #include <config.h>
  22 #endif
  23
  24 #include <stdlib.h>
  25 #include <stdio.h>
  26 #include <string.h>
  27
  28 #include <dbus/dbus.h>
  29
  30 #include <avahi-common/dbus.h>
  31 #include <avahi-common/llist.h>
  32 #include <avahi-common/error.h>
  33 #include <avahi-common/dbus.h>
  34 #include <avahi-common/malloc.h>
  35 #include <avahi-common/dbus-watch-glue.h>
  36 #include <avahi-common/i18n.h>
  37
  38 #include "client.h"
  39 #include "internal.h"
  40
  41 #define AVAHI_CLIENT_DBUS_API_SUPPORTED ((uint32_t) 0x0201)
  42
  43 static int init_server(AvahiClient *client, int *ret_error);
  44
  45 int avahi_client_set_errno (AvahiClient *client, int error) {
  46     assert(client);
  47
  48     return client->error = error;
  49 }
  50
  51 int avahi_client_set_dbus_error(AvahiClient *client, DBusError *error) {
  52     assert(client);
  53     assert(error);
  54
  55     return avahi_client_set_errno(client, avahi_error_dbus_to_number(error->name));
  56 }
  57
  58 static void client_set_state (AvahiClient *client, AvahiServerState state) {
  59     assert(client);
  60
  61     if (client->state == state)
  62         return;
  63
  64     client->state = state;
  65
  66     switch (client->state) {
  67         case AVAHI_CLIENT_FAILURE:
  68             if (client->bus) {
  69 #ifdef HAVE_DBUS_CONNECTION_CLOSE
  70                 dbus_connection_close(client->bus);
  71 #else
  72                 dbus_connection_disconnect(client->bus);
  73 #endif
  74                 dbus_connection_unref(client->bus);
  75                 client->bus = NULL;
  76             }
  77
  78             /* Fall through */
  79
  80         case AVAHI_CLIENT_S_COLLISION:
  81         case AVAHI_CLIENT_S_REGISTERING:
  82
  83             /* Clear cached strings */
  84             avahi_free(client->host_name);
  85             avahi_free(client->host_name_fqdn);
  86             avahi_free(client->domain_name);
  87
  88             client->host_name =  NULL;
  89             client->host_name_fqdn = NULL;
  90             client->domain_name = NULL;
  91             break;
  92
  93         case AVAHI_CLIENT_S_RUNNING:
  94         case AVAHI_CLIENT_CONNECTING:
  95             break;
  96
  97     }
  98
  99     if (client->callback)
 100         client->callback (client, state, client->userdata);
 101 }
 102
 103 static DBusHandlerResult filter_func(DBusConnection *bus, DBusMessage *message, void *userdata) {
 104     AvahiClient *client = userdata;
 105     DBusError error;
 106
 107     assert(bus);
 108     assert(message);
 109
 110     dbus_error_init(&error);
 111
 112 /*     fprintf(stderr, "dbus: interface=%s, path=%s, member=%s\n", */
 113 /*             dbus_message_get_interface (message), */
 114 /*             dbus_message_get_path (message), */
 115 /*             dbus_message_get_member (message)); */
 116
 117     if (dbus_message_is_signal(message, DBUS_INTERFACE_LOCAL, "Disconnected")) {
 118
 119         /* The DBUS server died or kicked us */
 120         avahi_client_set_errno(client, AVAHI_ERR_DISCONNECTED);
 121         goto fail;
 122
 123     } else if (dbus_message_is_signal(message, DBUS_INTERFACE_DBUS, "NameAcquired")) {
 124
 125         /* Ignore this message */
 126
 127     } else if (dbus_message_is_signal(message, DBUS_INTERFACE_DBUS, "NameOwnerChanged")) {
 128         char *name, *old, *new;
 129
 130         if (!dbus_message_get_args(
 131                   message, &error,
 132                   DBUS_TYPE_STRING, &name,
 133                   DBUS_TYPE_STRING, &old,
 134                   DBUS_TYPE_STRING, &new,
 135                   DBUS_TYPE_INVALID) || dbus_error_is_set(&error)) {
 136
 137             fprintf(stderr, "WARNING: Failed to parse NameOwnerChanged signal: %s\n", error.message);
 138             avahi_client_set_errno(client, AVAHI_ERR_DBUS_ERROR);
 139             goto fail;
 140         }
 141
 142         if (strcmp(name, AVAHI_DBUS_NAME) == 0) {
 143
 144             if (avahi_client_is_connected(client)) {
 145
 146                 /* Regardless if the server lost or acquired its name or
 147                  * if the name was transfered: our services are no longer
 148                  * available, so we disconnect ourselves */
 149                 avahi_client_set_errno(client, AVAHI_ERR_DISCONNECTED);
 150                 goto fail;
 151
 152             } else if (client->state == AVAHI_CLIENT_CONNECTING && (!old || *old == 0)) {
 153                 int ret;
 154
 155                 /* Server appeared */
 156
 157                 if ((ret = init_server(client, NULL)) < 0) {
 158                     avahi_client_set_errno(client, ret);
 159                     goto fail;
 160                 }
 161             }
 162         }
 163
 164     } else if (!avahi_client_is_connected(client)) {
 165
 166         /* Ignore messages we get in unconnected state */
 167
 168     } else if (dbus_message_is_signal (message, AVAHI_DBUS_INTERFACE_SERVER, "StateChanged")) {
 169         int32_t state;
 170         char *e = NULL;
 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) || dbus_error_is_set (&error)) {
 178
 179             fprintf(stderr, "WARNING: Failed to parse Server.StateChanged signal: %s\n", error.message);
 180             avahi_client_set_errno(client, AVAHI_ERR_DBUS_ERROR);
 181             goto fail;
 182         }
 183
 184         if ((c = avahi_error_dbus_to_number(e)) != AVAHI_OK)
 185             avahi_client_set_errno(client, c);
 186
 187         client_set_state(client, (AvahiClientState) state);
 188
 189     } else if (dbus_message_is_signal (message, AVAHI_DBUS_INTERFACE_ENTRY_GROUP, "StateChanged")) {
 190         const char *path;
 191         AvahiEntryGroup *g;
 192         path = dbus_message_get_path(message);
 193
 194         for (g = client->groups; g; g = g->groups_next)
 195             if (strcmp(g->path, path) == 0)
 196                 break;
 197
 198         if (g) {
 199             int32_t state;
 200             char *e;
 201             int c;
 202
 203             if (!dbus_message_get_args(
 204                       message, &error,
 205                       DBUS_TYPE_INT32, &state,
 206                       DBUS_TYPE_STRING, &e,
 207                       DBUS_TYPE_INVALID) ||
 208                 dbus_error_is_set(&error)) {
 209
 210                 fprintf(stderr, "WARNING: Failed to parse EntryGroup.StateChanged signal: %s\n", error.message);
 211                 avahi_client_set_errno(client, AVAHI_ERR_DBUS_ERROR);
 212                 goto fail;
 213             }
 214
 215             if ((c = avahi_error_dbus_to_number(e)) != AVAHI_OK)
 216                 avahi_client_set_errno(client, c);
 217
 218             avahi_entry_group_set_state(g, state);
 219         }
 220
 221     } else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_DOMAIN_BROWSER, "ItemNew"))
 222         return avahi_domain_browser_event(client, AVAHI_BROWSER_NEW, message);
 223     else if (dbus_message_is_signal (message, AVAHI_DBUS_INTERFACE_DOMAIN_BROWSER, "ItemRemove"))
 224         return avahi_domain_browser_event(client, AVAHI_BROWSER_REMOVE, message);
 225     else if (dbus_message_is_signal (message, AVAHI_DBUS_INTERFACE_DOMAIN_BROWSER, "CacheExhausted"))
 226         return avahi_domain_browser_event(client, AVAHI_BROWSER_CACHE_EXHAUSTED, message);
 227     else if (dbus_message_is_signal (message, AVAHI_DBUS_INTERFACE_DOMAIN_BROWSER, "AllForNow"))
 228         return avahi_domain_browser_event(client, AVAHI_BROWSER_ALL_FOR_NOW, message);
 229     else if (dbus_message_is_signal (message, AVAHI_DBUS_INTERFACE_DOMAIN_BROWSER, "Failure"))
 230         return avahi_domain_browser_event(client, AVAHI_BROWSER_FAILURE, message);
 231
 232     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_SERVICE_TYPE_BROWSER, "ItemNew"))
 233         return avahi_service_type_browser_event (client, AVAHI_BROWSER_NEW, message);
 234     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_SERVICE_TYPE_BROWSER, "ItemRemove"))
 235         return avahi_service_type_browser_event (client, AVAHI_BROWSER_REMOVE, message);
 236     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_SERVICE_TYPE_BROWSER, "CacheExhausted"))
 237         return avahi_service_type_browser_event (client, AVAHI_BROWSER_CACHE_EXHAUSTED, message);
 238     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_SERVICE_TYPE_BROWSER, "AllForNow"))
 239         return avahi_service_type_browser_event (client, AVAHI_BROWSER_ALL_FOR_NOW, message);
 240     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_SERVICE_TYPE_BROWSER, "Failure"))
 241         return avahi_service_type_browser_event (client, AVAHI_BROWSER_FAILURE, message);
 242
 243     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_SERVICE_BROWSER, "ItemNew"))
 244         return avahi_service_browser_event (client, AVAHI_BROWSER_NEW, message);
 245     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_SERVICE_BROWSER, "ItemRemove"))
 246         return avahi_service_browser_event (client, AVAHI_BROWSER_REMOVE, message);
 247     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_SERVICE_BROWSER, "CacheExhausted"))
 248         return avahi_service_browser_event (client, AVAHI_BROWSER_CACHE_EXHAUSTED, message);
 249     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_SERVICE_BROWSER, "AllForNow"))
 250         return avahi_service_browser_event (client, AVAHI_BROWSER_ALL_FOR_NOW, message);
 251     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_SERVICE_BROWSER, "Failure"))
 252         return avahi_service_browser_event (client, AVAHI_BROWSER_FAILURE, message);
 253
 254     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_SERVICE_RESOLVER, "Found"))
 255         return avahi_service_resolver_event (client, AVAHI_RESOLVER_FOUND, message);
 256     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_SERVICE_RESOLVER, "Failure"))
 257         return avahi_service_resolver_event (client, AVAHI_RESOLVER_FAILURE, message);
 258
 259     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_HOST_NAME_RESOLVER, "Found"))
 260         return avahi_host_name_resolver_event (client, AVAHI_RESOLVER_FOUND, message);
 261     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_HOST_NAME_RESOLVER, "Failure"))
 262         return avahi_host_name_resolver_event (client, AVAHI_RESOLVER_FAILURE, message);
 263
 264     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_ADDRESS_RESOLVER, "Found"))
 265         return avahi_address_resolver_event (client, AVAHI_RESOLVER_FOUND, message);
 266     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_ADDRESS_RESOLVER, "Failure"))
 267         return avahi_address_resolver_event (client, AVAHI_RESOLVER_FAILURE, message);
 268
 269     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_RECORD_BROWSER, "ItemNew"))
 270         return avahi_record_browser_event (client, AVAHI_BROWSER_NEW, message);
 271     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_RECORD_BROWSER, "ItemRemove"))
 272         return avahi_record_browser_event (client, AVAHI_BROWSER_REMOVE, message);
 273     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_RECORD_BROWSER, "CacheExhausted"))
 274         return avahi_record_browser_event (client, AVAHI_BROWSER_CACHE_EXHAUSTED, message);
 275     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_RECORD_BROWSER, "AllForNow"))
 276         return avahi_record_browser_event (client, AVAHI_BROWSER_ALL_FOR_NOW, message);
 277     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_RECORD_BROWSER, "Failure"))
 278         return avahi_record_browser_event (client, AVAHI_BROWSER_FAILURE, message);
 279
 280     else {
 281
 282         fprintf(stderr, "WARNING: Unhandled message: interface=%s, path=%s, member=%s\n",
 283                dbus_message_get_interface(message),
 284                dbus_message_get_path(message),
 285                dbus_message_get_member(message));
 286
 287         return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
 288     }
 289
 290     return DBUS_HANDLER_RESULT_HANDLED;
 291
 292 fail:
 293
 294     if (dbus_error_is_set(&error)) {
 295         avahi_client_set_errno(client, avahi_error_dbus_to_number(error.name));
 296         dbus_error_free(&error);
 297     }
 298
 299     client_set_state(client, AVAHI_CLIENT_FAILURE);
 300
 301     return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
 302 }
 303
 304 static int get_server_state(AvahiClient *client, int *ret_error) {
 305     DBusMessage *message = NULL, *reply = NULL;
 306     DBusError error;
 307     int32_t state;
 308     int e = AVAHI_ERR_NO_MEMORY;
 309
 310     assert(client);
 311
 312     dbus_error_init(&error);
 313
 314     if (!(message = dbus_message_new_method_call(AVAHI_DBUS_NAME, AVAHI_DBUS_PATH_SERVER, AVAHI_DBUS_INTERFACE_SERVER, "GetState")))
 315         goto fail;
 316
 317     reply = dbus_connection_send_with_reply_and_block (client->bus, message, -1, &error);
 318
 319     if (!reply || dbus_error_is_set (&error))
 320         goto fail;
 321
 322     if (!dbus_message_get_args(reply, &error, DBUS_TYPE_INT32, &state, DBUS_TYPE_INVALID) ||
 323         dbus_error_is_set (&error))
 324         goto fail;
 325
 326     client_set_state(client, (AvahiServerState) state);
 327
 328     dbus_message_unref(message);
 329     dbus_message_unref(reply);
 330
 331     return AVAHI_OK;
 332
 333 fail:
 334     if (dbus_error_is_set(&error)) {
 335         e = avahi_error_dbus_to_number (error.name);
 336         dbus_error_free(&error);
 337     }
 338
 339     if (ret_error)
 340         *ret_error = e;
 341
 342     if (message)
 343         dbus_message_unref(message);
 344     if (reply)
 345         dbus_message_unref(reply);
 346
 347     return e;
 348 }
 349
 350 static int check_version(AvahiClient *client, int *ret_error) {
 351     DBusMessage *message = NULL, *reply  = NULL;
 352     DBusError error;
 353     uint32_t version;
 354     int e = AVAHI_ERR_NO_MEMORY;
 355
 356     assert(client);
 357
 358     dbus_error_init(&error);
 359
 360     if (!(message = dbus_message_new_method_call(AVAHI_DBUS_NAME, AVAHI_DBUS_PATH_SERVER, AVAHI_DBUS_INTERFACE_SERVER, "GetAPIVersion")))
 361         goto fail;
 362
 363     reply = dbus_connection_send_with_reply_and_block (client->bus, message, -1, &error);
 364
 365     if (!reply || dbus_error_is_set (&error)) {
 366         char *version_str;
 367
 368         if (!dbus_error_is_set(&error) || strcmp(error.name, DBUS_ERROR_UNKNOWN_METHOD))
 369             goto fail;
 370
 371         /* If the method GetAPIVersion is not known, we look if
 372          * GetVersionString matches "avahi 0.6" which is the only
 373          * version we support which doesn't have GetAPIVersion() .*/
 374
 375         dbus_message_unref(message);
 376         if (reply) dbus_message_unref(reply);
 377         dbus_error_free(&error);
 378
 379         if (!(message = dbus_message_new_method_call(AVAHI_DBUS_NAME, AVAHI_DBUS_PATH_SERVER, AVAHI_DBUS_INTERFACE_SERVER, "GetVersionString")))
 380             goto fail;
 381
 382         reply = dbus_connection_send_with_reply_and_block (client->bus, message, -1, &error);
 383
 384         if (!reply || dbus_error_is_set (&error))
 385             goto fail;
 386
 387         if (!dbus_message_get_args (reply, &error, DBUS_TYPE_STRING, &version_str, DBUS_TYPE_INVALID) ||
 388             dbus_error_is_set (&error))
 389             goto fail;
 390
 391         version = strcmp(version_str, "avahi 0.6") == 0 ? 0x0201 : 0x0000;
 392
 393     } else {
 394
 395         if (!dbus_message_get_args (reply, &error, DBUS_TYPE_UINT32, &version, DBUS_TYPE_INVALID) ||
 396             dbus_error_is_set(&error))
 397             goto fail;
 398     }
 399
 400     /*fprintf(stderr, "API Version 0x%04x\n", version);*/
 401
 402     if ((version & 0xFF00) != (AVAHI_CLIENT_DBUS_API_SUPPORTED & 0xFF00) ||
 403         (version & 0x00FF) < (AVAHI_CLIENT_DBUS_API_SUPPORTED & 0x00FF)) {
 404         e = AVAHI_ERR_VERSION_MISMATCH;
 405         goto fail;
 406     }
 407
 408     dbus_message_unref(message);
 409     dbus_message_unref(reply);
 410
 411     return AVAHI_OK;
 412
 413 fail:
 414     if (dbus_error_is_set(&error)) {
 415         e = avahi_error_dbus_to_number (error.name);
 416         dbus_error_free(&error);
 417     }
 418
 419     if (ret_error)
 420         *ret_error = e;
 421
 422     if (message)
 423         dbus_message_unref(message);
 424     if (reply)
 425         dbus_message_unref(reply);
 426
 427     return e;
 428 }
 429
 430 static int init_server(AvahiClient *client, int *ret_error) {
 431     int r;
 432
 433     if ((r = check_version(client, ret_error)) < 0)
 434         return r;
 435
 436     if ((r = get_server_state(client, ret_error)) < 0)
 437         return r;
 438
 439     return AVAHI_OK;
 440 }
 441
 442 /* This function acts like dbus_bus_get but creates a private
 443  * connection instead.  */
 444 static DBusConnection* avahi_dbus_bus_get(DBusError *error) {
 445     DBusConnection *c;
 446
 447 #ifdef HAVE_DBUS_BUS_GET_PRIVATE
 448     if (!(c = dbus_bus_get_private(DBUS_BUS_SYSTEM, error)))
 449         return NULL;
 450
 451     dbus_connection_set_exit_on_disconnect(c, FALSE);
 452 #else
 453     const char *a;
 454
 455     if (!(a = getenv("DBUS_SYSTEM_BUS_ADDRESS")) || !*a)
 456         a = DBUS_SYSTEM_BUS_DEFAULT_ADDRESS;
 457
 458     if (!(c = dbus_connection_open_private(a, error)))
 459         return NULL;
 460
 461     dbus_connection_set_exit_on_disconnect(c, FALSE);
 462
 463     if (!dbus_bus_register(c, error)) {
 464 #ifdef HAVE_DBUS_CONNECTION_CLOSE
 465         dbus_connection_close(c);
 466 #else
 467         dbus_connection_disconnect(c);
 468 #endif
 469         dbus_connection_unref(c);
 470         return NULL;
 471     }
 472 #endif
 473
 474     return c;
 475 }
 476
 477 AvahiClient *avahi_client_new(const AvahiPoll *poll_api, AvahiClientFlags flags, AvahiClientCallback callback, void *userdata, int *ret_error) {
 478     AvahiClient *client = NULL;
 479     DBusError error;
 480
 481     avahi_init_i18n();
 482
 483     dbus_error_init(&error);
 484
 485     if (!(client = avahi_new(AvahiClient, 1))) {
 486         if (ret_error)
 487             *ret_error = AVAHI_ERR_NO_MEMORY;
 488         goto fail;
 489     }
 490
 491     client->poll_api = poll_api;
 492     client->error = AVAHI_OK;
 493     client->callback = callback;
 494     client->userdata = userdata;
 495     client->state = (AvahiClientState) -1;
 496     client->flags = flags;
 497
 498     client->host_name = NULL;
 499     client->host_name_fqdn = NULL;
 500     client->domain_name = NULL;
 501     client->version_string = NULL;
 502     client->local_service_cookie_valid = 0;
 503
 504     AVAHI_LLIST_HEAD_INIT(AvahiEntryGroup, client->groups);
 505     AVAHI_LLIST_HEAD_INIT(AvahiDomainBrowser, client->domain_browsers);
 506     AVAHI_LLIST_HEAD_INIT(AvahiServiceBrowser, client->service_browsers);
 507     AVAHI_LLIST_HEAD_INIT(AvahiServiceTypeBrowser, client->service_type_browsers);
 508     AVAHI_LLIST_HEAD_INIT(AvahiServiceResolver, client->service_resolvers);
 509     AVAHI_LLIST_HEAD_INIT(AvahiHostNameResolver, client->host_name_resolvers);
 510     AVAHI_LLIST_HEAD_INIT(AvahiAddressResolver, client->address_resolvers);
 511     AVAHI_LLIST_HEAD_INIT(AvahiRecordBrowser, client->record_browsers);
 512
 513     if (!(client->bus = avahi_dbus_bus_get(&error)) || dbus_error_is_set(&error)) {
 514         if (ret_error)
 515             *ret_error = AVAHI_ERR_DBUS_ERROR;
 516         goto fail;
 517     }
 518
 519     if (avahi_dbus_connection_glue(client->bus, poll_api) < 0) {
 520         if (ret_error)
 521             *ret_error = AVAHI_ERR_NO_MEMORY; /* Not optimal */
 522         goto fail;
 523     }
 524
 525     if (!dbus_connection_add_filter (client->bus, filter_func, client, NULL)) {
 526         if (ret_error)
 527             *ret_error = AVAHI_ERR_NO_MEMORY;
 528         goto fail;
 529     }
 530
 531     dbus_bus_add_match(
 532         client->bus,
 533         "type='signal', "
 534         "interface='" AVAHI_DBUS_INTERFACE_SERVER "', "
 535         "sender='" AVAHI_DBUS_NAME "', "
 536         "path='" AVAHI_DBUS_PATH_SERVER "'",
 537         &error);
 538
 539     if (dbus_error_is_set(&error))
 540         goto fail;
 541
 542     dbus_bus_add_match (
 543         client->bus,
 544         "type='signal', "
 545         "interface='" DBUS_INTERFACE_DBUS "', "
 546         "sender='" DBUS_SERVICE_DBUS "', "
 547         "path='" DBUS_PATH_DBUS "'",
 548         &error);
 549
 550     if (dbus_error_is_set(&error))
 551         goto fail;
 552
 553     dbus_bus_add_match (
 554         client->bus,
 555         "type='signal', "
 556         "interface='" DBUS_INTERFACE_LOCAL "'",
 557         &error);
 558
 559     if (dbus_error_is_set(&error))
 560         goto fail;
 561
 562
 563     if (!(dbus_bus_name_has_owner(client->bus, AVAHI_DBUS_NAME, &error)) ||
 564         dbus_error_is_set(&error)) {
 565
 566         /* We free the error so its not set, that way the fail target
 567          * will return the NO_DAEMON error rather than a DBUS error */
 568         dbus_error_free(&error);
 569
 570         if (!(flags & AVAHI_CLIENT_NO_FAIL)) {
 571
 572             if (ret_error)
 573                 *ret_error = AVAHI_ERR_NO_DAEMON;
 574
 575             goto fail;
 576         }
 577
 578         /* The user doesn't want this call to fail if the daemon is not
 579          * available, so let's return succesfully */
 580         client_set_state(client, AVAHI_CLIENT_CONNECTING);
 581
 582     } else {
 583
 584         if (init_server(client, ret_error) < 0)
 585             goto fail;
 586     }
 587
 588     return client;
 589
 590 fail:
 591
 592     if (client)
 593         avahi_client_free(client);
 594
 595     if (dbus_error_is_set(&error)) {
 596
 597         if (ret_error) {
 598             if (strcmp(error.name, DBUS_ERROR_FILE_NOT_FOUND) == 0)
 599                 /* DBUS returns this error when the DBUS daemon is not running */
 600                 *ret_error = AVAHI_ERR_NO_DAEMON;
 601             else
 602                 *ret_error = avahi_error_dbus_to_number(error.name);
 603         }
 604
 605         dbus_error_free(&error);
 606     }
 607
 608     return NULL;
 609 }
 610
 611 void avahi_client_free(AvahiClient *client) {
 612     assert(client);
 613
 614     if (client->bus)
 615         /* Disconnect in advance, so that the free() functions won't
 616          * issue needless server calls */
 617 #ifdef HAVE_DBUS_CONNECTION_CLOSE
 618         dbus_connection_close(client->bus);
 619 #else
 620         dbus_connection_disconnect(client->bus);
 621 #endif
 622
 623     while (client->groups)
 624         avahi_entry_group_free(client->groups);
 625
 626     while (client->domain_browsers)
 627         avahi_domain_browser_free(client->domain_browsers);
 628
 629     while (client->service_browsers)
 630         avahi_service_browser_free(client->service_browsers);
 631
 632     while (client->service_type_browsers)
 633         avahi_service_type_browser_free(client->service_type_browsers);
 634
 635     while (client->service_resolvers)
 636         avahi_service_resolver_free(client->service_resolvers);
 637
 638     while (client->host_name_resolvers)
 639         avahi_host_name_resolver_free(client->host_name_resolvers);
 640
 641     while (client->address_resolvers)
 642         avahi_address_resolver_free(client->address_resolvers);
 643
 644     while (client->record_browsers)
 645         avahi_record_browser_free(client->record_browsers);
 646
 647     if (client->bus)
 648         dbus_connection_unref(client->bus);
 649
 650     avahi_free(client->version_string);
 651     avahi_free(client->host_name);
 652     avahi_free(client->host_name_fqdn);
 653     avahi_free(client->domain_name);
 654
 655     avahi_free(client);
 656 }
 657
 658 static char* avahi_client_get_string_reply_and_block (AvahiClient *client, const char *method, const char *param) {
 659     DBusMessage *message = NULL, *reply = NULL;
 660     DBusError error;
 661     char *ret, *n;
 662
 663     assert(client);
 664     assert(method);
 665
 666     dbus_error_init (&error);
 667
 668     if (!(message = dbus_message_new_method_call (AVAHI_DBUS_NAME, AVAHI_DBUS_PATH_SERVER, AVAHI_DBUS_INTERFACE_SERVER, method))) {
 669         avahi_client_set_errno(client, AVAHI_ERR_NO_MEMORY);
 670         goto fail;
 671     }
 672
 673     if (param) {
 674         if (!dbus_message_append_args (message, DBUS_TYPE_STRING, &param, DBUS_TYPE_INVALID)) {
 675             avahi_client_set_errno (client, AVAHI_ERR_NO_MEMORY);
 676             goto fail;
 677         }
 678     }
 679
 680     reply = dbus_connection_send_with_reply_and_block (client->bus, message, -1, &error);
 681
 682     if (!reply || dbus_error_is_set (&error))
 683         goto fail;
 684
 685     if (!dbus_message_get_args (reply, &error, DBUS_TYPE_STRING, &ret, DBUS_TYPE_INVALID) ||
 686         dbus_error_is_set (&error))
 687         goto fail;
 688
 689     if (!(n = avahi_strdup(ret))) {
 690         avahi_client_set_errno(client, AVAHI_ERR_NO_MEMORY);
 691         goto fail;
 692     }
 693
 694     dbus_message_unref(message);
 695     dbus_message_unref(reply);
 696
 697     return n;
 698
 699 fail:
 700
 701     if (message)
 702         dbus_message_unref(message);
 703     if (reply)
 704         dbus_message_unref(reply);
 705
 706     if (dbus_error_is_set(&error)) {
 707         avahi_client_set_dbus_error(client, &error);
 708         dbus_error_free(&error);
 709     }
 710
 711     return NULL;
 712 }
 713
 714 const char* avahi_client_get_version_string(AvahiClient *client) {
 715     assert(client);
 716
 717     if (!avahi_client_is_connected(client)) {
 718         avahi_client_set_errno(client, AVAHI_ERR_BAD_STATE);
 719         return NULL;
 720     }
 721
 722     if (!client->version_string)
 723         client->version_string = avahi_client_get_string_reply_and_block(client, "GetVersionString", NULL);
 724
 725     return client->version_string;
 726 }
 727
 728 const char* avahi_client_get_domain_name(AvahiClient *client) {
 729     assert(client);
 730
 731     if (!avahi_client_is_connected(client)) {
 732         avahi_client_set_errno(client, AVAHI_ERR_BAD_STATE);
 733         return NULL;
 734     }
 735
 736     if (!client->domain_name)
 737         client->domain_name = avahi_client_get_string_reply_and_block(client, "GetDomainName", NULL);
 738
 739     return client->domain_name;
 740 }
 741
 742 const char* avahi_client_get_host_name(AvahiClient *client) {
 743     assert(client);
 744
 745     if (!avahi_client_is_connected(client)) {
 746         avahi_client_set_errno(client, AVAHI_ERR_BAD_STATE);
 747         return NULL;
 748     }
 749
 750     if (!client->host_name)
 751         client->host_name = avahi_client_get_string_reply_and_block(client, "GetHostName", NULL);
 752
 753     return client->host_name;
 754 }
 755
 756 const char* avahi_client_get_host_name_fqdn (AvahiClient *client) {
 757     assert(client);
 758
 759     if (!avahi_client_is_connected(client)) {
 760         avahi_client_set_errno(client, AVAHI_ERR_BAD_STATE);
 761         return NULL;
 762     }
 763
 764     if (!client->host_name_fqdn)
 765         client->host_name_fqdn = avahi_client_get_string_reply_and_block(client, "GetHostNameFqdn", NULL);
 766
 767     return client->host_name_fqdn;
 768 }
 769
 770 AvahiClientState avahi_client_get_state(AvahiClient *client) {
 771     assert(client);
 772
 773     return client->state;
 774 }
 775
 776 int avahi_client_errno(AvahiClient *client) {
 777     assert(client);
 778
 779     return client->error;
 780 }
 781
 782 /* Just for internal use */
 783 int avahi_client_simple_method_call(AvahiClient *client, const char *path, const char *interface, const char *method) {
 784     DBusMessage *message = NULL, *reply = NULL;
 785     DBusError error;
 786     int r = AVAHI_OK;
 787
 788     dbus_error_init(&error);
 789
 790     assert(client);
 791     assert(path);
 792     assert(interface);
 793     assert(method);
 794
 795     if (!(message = dbus_message_new_method_call(AVAHI_DBUS_NAME, path, interface, method))) {
 796         r = avahi_client_set_errno(client, AVAHI_ERR_NO_MEMORY);
 797         goto fail;
 798     }
 799
 800     if (!(reply = dbus_connection_send_with_reply_and_block(client->bus, message, -1, &error)) ||
 801         dbus_error_is_set (&error)) {
 802         r = avahi_client_set_errno(client, AVAHI_ERR_DBUS_ERROR);
 803         goto fail;
 804     }
 805
 806     if (!dbus_message_get_args(reply, &error, DBUS_TYPE_INVALID) ||
 807         dbus_error_is_set (&error)) {
 808         r = avahi_client_set_errno(client, AVAHI_ERR_DBUS_ERROR);
 809         goto fail;
 810     }
 811
 812     dbus_message_unref(message);
 813     dbus_message_unref(reply);
 814
 815     return AVAHI_OK;
 816
 817 fail:
 818     if (dbus_error_is_set(&error)) {
 819         r = avahi_client_set_dbus_error(client, &error);
 820         dbus_error_free(&error);
 821     }
 822
 823     if (message)
 824         dbus_message_unref(message);
 825
 826     if (reply)
 827         dbus_message_unref(reply);
 828
 829     return r;
 830 }
 831
 832 uint32_t avahi_client_get_local_service_cookie(AvahiClient *client) {
 833     DBusMessage *message = NULL, *reply = NULL;
 834     DBusError error;
 835     assert(client);
 836
 837     if (!avahi_client_is_connected(client)) {
 838         avahi_client_set_errno(client, AVAHI_ERR_BAD_STATE);
 839         return AVAHI_SERVICE_COOKIE_INVALID;
 840     }
 841
 842     if (client->local_service_cookie_valid)
 843         return client->local_service_cookie;
 844
 845     dbus_error_init (&error);
 846
 847     if (!(message = dbus_message_new_method_call(AVAHI_DBUS_NAME, AVAHI_DBUS_PATH_SERVER, AVAHI_DBUS_INTERFACE_SERVER, "GetLocalServiceCookie"))) {
 848         avahi_client_set_errno(client, AVAHI_ERR_NO_MEMORY);
 849         goto fail;
 850     }
 851
 852     reply = dbus_connection_send_with_reply_and_block (client->bus, message, -1, &error);
 853
 854     if (!reply || dbus_error_is_set (&error))
 855         goto fail;
 856
 857     if (!dbus_message_get_args (reply, &error, DBUS_TYPE_UINT32, &client->local_service_cookie, DBUS_TYPE_INVALID) ||
 858         dbus_error_is_set (&error))
 859         goto fail;
 860
 861     dbus_message_unref(message);
 862     dbus_message_unref(reply);
 863
 864     client->local_service_cookie_valid = 1;
 865     return client->local_service_cookie;
 866
 867 fail:
 868
 869     if (message)
 870         dbus_message_unref(message);
 871     if (reply)
 872         dbus_message_unref(reply);
 873
 874     if (dbus_error_is_set(&error)) {
 875         avahi_client_set_dbus_error(client, &error);
 876         dbus_error_free(&error);
 877     }
 878
 879     return AVAHI_SERVICE_COOKIE_INVALID;
 880 }
 881
 882 int avahi_client_is_connected(AvahiClient *client) {
 883     assert(client);
 884
 885     return
 886         client->bus &&
 887         dbus_connection_get_is_connected(client->bus) &&
 888         (client->state == AVAHI_CLIENT_S_RUNNING || client->state == AVAHI_CLIENT_S_REGISTERING || client->state == AVAHI_CLIENT_S_COLLISION);
 889 }
 890
 891 int avahi_client_set_host_name(AvahiClient* client, const char *name) {
 892     DBusMessage *message = NULL, *reply = NULL;
 893     DBusError error;
 894
 895     assert(client);
 896
 897     if (!avahi_client_is_connected(client))
 898         return avahi_client_set_errno(client, AVAHI_ERR_BAD_STATE);
 899
 900     dbus_error_init (&error);
 901
 902     if (!(message = dbus_message_new_method_call (AVAHI_DBUS_NAME, AVAHI_DBUS_PATH_SERVER, AVAHI_DBUS_INTERFACE_SERVER, "SetHostName"))) {
 903         avahi_client_set_errno(client, AVAHI_ERR_NO_MEMORY);
 904         goto fail;
 905     }
 906
 907     if (!dbus_message_append_args (message, DBUS_TYPE_STRING, &name, DBUS_TYPE_INVALID)) {
 908         avahi_client_set_errno (client, AVAHI_ERR_NO_MEMORY);
 909         goto fail;
 910     }
 911
 912     reply = dbus_connection_send_with_reply_and_block(client->bus, message, -1, &error);
 913
 914     if (!reply || dbus_error_is_set (&error))
 915         goto fail;
 916
 917     if (!dbus_message_get_args(reply, &error, DBUS_TYPE_INVALID) ||
 918         dbus_error_is_set (&error))
 919         goto fail;
 920
 921     dbus_message_unref(message);
 922     dbus_message_unref(reply);
 923
 924     avahi_free(client->host_name);
 925     client->host_name = NULL;
 926     avahi_free(client->host_name_fqdn);
 927     client->host_name_fqdn = NULL;
 928
 929     return 0;
 930
 931 fail:
 932
 933     if (message)
 934         dbus_message_unref(message);
 935     if (reply)
 936         dbus_message_unref(reply);
 937
 938     if (dbus_error_is_set(&error)) {
 939         avahi_client_set_dbus_error(client, &error);
 940         dbus_error_free(&error);
 941     }
 942
 943     return client->error;
 944 }