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
 178     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_SERVICE_TYPE_BROWSER, "ItemNew"))
 179         return avahi_service_type_browser_event (client, AVAHI_BROWSER_NEW, message);
 180     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_SERVICE_TYPE_BROWSER, "ItemRemove"))
 181         return avahi_service_type_browser_event (client, AVAHI_BROWSER_REMOVE, message);
 182
 183     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_SERVICE_BROWSER, "ItemNew"))
 184         return avahi_service_browser_event (client, AVAHI_BROWSER_NEW, message);
 185     else if (dbus_message_is_signal(message, AVAHI_DBUS_INTERFACE_SERVICE_BROWSER, "ItemRemove"))
 186         return avahi_service_browser_event (client, AVAHI_BROWSER_REMOVE, message);
 187
 188     return DBUS_HANDLER_RESULT_HANDLED;
 189
 190 fail:
 191
 192     dbus_error_free (&error);
 193     return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
 194 }
 195
 196 static int get_server_state(AvahiClient *client, int *ret_error) {
 197     DBusMessage *message, *reply;
 198     DBusError error;
 199     int32_t state;
 200     int e;
 201
 202     assert(client);
 203
 204     dbus_error_init(&error);
 205
 206     if (!(message = dbus_message_new_method_call(AVAHI_DBUS_NAME, AVAHI_DBUS_PATH_SERVER, AVAHI_DBUS_INTERFACE_SERVER, "GetState")))
 207         goto fail;
 208
 209     reply = dbus_connection_send_with_reply_and_block (client->bus, message, -1, &error);
 210     dbus_message_unref(message);
 211
 212     if (!reply)
 213         goto fail;
 214
 215     if (!(dbus_message_get_args(reply, &error, DBUS_TYPE_INT32, &state, DBUS_TYPE_INVALID)))
 216         goto fail;
 217
 218     client_set_state(client, (AvahiServerState) state);
 219
 220     return AVAHI_OK;
 221
 222 fail:
 223     if (dbus_error_is_set(&error)) {
 224         e = avahi_error_dbus_to_number (error.name);
 225         dbus_error_free(&error);
 226     } else
 227         e = AVAHI_ERR_NO_MEMORY;
 228
 229     if (ret_error)
 230         *ret_error = e;
 231
 232     return e;
 233 }
 234
 235 /* This function acts like dbus_bus_get but creates a private
 236  * connection instead */
 237 static DBusConnection*
 238 avahi_dbus_bus_get (DBusError *error)
 239 {
 240     DBusConnection *conn;
 241     char *env_addr;
 242
 243     env_addr = getenv ("DBUS_SYSTEM_BUS_ADDRESS");
 244
 245     if (env_addr == NULL || (*env_addr == 0))
 246     {
 247         env_addr = DBUS_SYSTEM_BUS_DEFAULT_ADDRESS;
 248     }
 249
 250     conn = dbus_connection_open_private (env_addr, error);
 251
 252     if (!conn)
 253         return NULL;
 254
 255     dbus_connection_set_exit_on_disconnect (conn, FALSE);
 256
 257     if (!dbus_bus_register (conn, error))
 258     {
 259         dbus_connection_close (conn);
 260         dbus_connection_unref (conn);
 261
 262         return NULL;
 263     }
 264
 265     return conn;
 266 }
 267
 268 AvahiClient *avahi_client_new(const AvahiPoll *poll_api, AvahiClientCallback callback, void *userdata, int *ret_error) {
 269     AvahiClient *client = NULL;
 270     DBusError error;
 271
 272     dbus_error_init (&error);
 273
 274     if (!(client = avahi_new(AvahiClient, 1))) {
 275         if (ret_error)
 276             *ret_error = AVAHI_ERR_NO_MEMORY;
 277         goto fail;
 278     }
 279
 280     client->poll_api = poll_api;
 281     client->error = AVAHI_OK;
 282     client->callback = callback;
 283     client->userdata = userdata;
 284     client->state = AVAHI_CLIENT_DISCONNECTED;
 285
 286     client->host_name = NULL;
 287     client->host_name_fqdn = NULL;
 288     client->domain_name = NULL;
 289     client->version_string = NULL;
 290
 291     AVAHI_LLIST_HEAD_INIT(AvahiEntryGroup, client->groups);
 292     AVAHI_LLIST_HEAD_INIT(AvahiDomainBrowser, client->domain_browsers);
 293     AVAHI_LLIST_HEAD_INIT(AvahiServiceBrowser, client->service_browsers);
 294     AVAHI_LLIST_HEAD_INIT(AvahiServiceTypeBrowser, client->service_type_browsers);
 295     AVAHI_LLIST_HEAD_INIT(AvahiServiceResolver, client->service_resolvers);
 296     AVAHI_LLIST_HEAD_INIT(AvahiHostNameResolver, client->host_name_resolvers);
 297     AVAHI_LLIST_HEAD_INIT(AvahiAddressResolver, client->address_resolvers);
 298
 299     if (!(client->bus = avahi_dbus_bus_get(&error)) ||
 300         dbus_error_is_set (&error))
 301         goto fail;
 302
 303     if (avahi_dbus_connection_glue(client->bus, poll_api) < 0) {
 304         if (ret_error)
 305             *ret_error = AVAHI_ERR_NO_MEMORY; /* Not optimal */
 306         goto fail;
 307     }
 308
 309     if (!dbus_connection_add_filter (client->bus, filter_func, client, NULL)) {
 310         if (ret_error)
 311             *ret_error = AVAHI_ERR_NO_MEMORY;
 312         goto fail;
 313     }
 314
 315     dbus_bus_add_match(
 316         client->bus,
 317         "type='signal', "
 318         "interface='" AVAHI_DBUS_INTERFACE_SERVER "', "
 319         "sender='" AVAHI_DBUS_NAME "', "
 320         "path='" AVAHI_DBUS_PATH_SERVER "'",
 321         &error);
 322
 323     if (dbus_error_is_set (&error))
 324         goto fail;
 325
 326     dbus_bus_add_match (
 327         client->bus,
 328         "type='signal', "
 329         "interface='" DBUS_INTERFACE_DBUS "', "
 330         "sender='" DBUS_SERVICE_DBUS "', "
 331         "path='" DBUS_PATH_DBUS "'",
 332         &error);
 333
 334     if (dbus_error_is_set (&error))
 335         goto fail;
 336
 337         dbus_bus_add_match (
 338         client->bus,
 339         "type='signal', "
 340         "interface='" DBUS_INTERFACE_LOCAL "'",
 341         &error);
 342
 343     if (dbus_error_is_set (&error))
 344         goto fail;
 345
 346     if (!(dbus_bus_name_has_owner(client->bus, AVAHI_DBUS_NAME, &error)) ||
 347         dbus_error_is_set(&error)) {
 348
 349         if (ret_error)
 350             *ret_error = AVAHI_ERR_NO_DAEMON;
 351
 352         goto fail;
 353     }
 354
 355     if (get_server_state(client, ret_error) < 0)
 356         goto fail;
 357
 358     return client;
 359
 360 fail:
 361
 362     if (client)
 363         avahi_client_free(client);
 364
 365     if (dbus_error_is_set(&error)) {
 366
 367         if (ret_error)
 368             *ret_error = avahi_error_dbus_to_number(error.name);
 369
 370         dbus_error_free(&error);
 371     }
 372
 373     return NULL;
 374 }
 375
 376 void avahi_client_free(AvahiClient *client) {
 377     assert(client);
 378
 379     while (client->groups)
 380         avahi_entry_group_free(client->groups);
 381
 382     while (client->domain_browsers)
 383         avahi_domain_browser_free(client->domain_browsers);
 384
 385     while (client->service_browsers)
 386         avahi_service_browser_free(client->service_browsers);
 387
 388     while (client->service_type_browsers)
 389         avahi_service_type_browser_free(client->service_type_browsers);
 390
 391     while (client->service_resolvers)
 392         avahi_service_resolver_free(client->service_resolvers);
 393
 394     if (client->bus) {
 395         dbus_connection_disconnect(client->bus);
 396         dbus_connection_unref(client->bus);
 397     }
 398
 399     avahi_free(client->version_string);
 400     avahi_free(client->host_name);
 401     avahi_free(client->host_name_fqdn);
 402     avahi_free(client->domain_name);
 403
 404     avahi_free(client);
 405 }
 406
 407 static char* avahi_client_get_string_reply_and_block (AvahiClient *client, const char *method, const char *param) {
 408     DBusMessage *message = NULL, *reply = NULL;
 409     DBusError error;
 410     char *ret, *n;
 411
 412     assert(client);
 413     assert(method);
 414
 415     dbus_error_init (&error);
 416
 417     if (!(message = dbus_message_new_method_call (AVAHI_DBUS_NAME, AVAHI_DBUS_PATH_SERVER, AVAHI_DBUS_INTERFACE_SERVER, method))) {
 418         avahi_client_set_errno(client, AVAHI_ERR_NO_MEMORY);
 419         goto fail;
 420     }
 421
 422     if (param) {
 423         if (!dbus_message_append_args (message, DBUS_TYPE_STRING, &param, DBUS_TYPE_INVALID)) {
 424             avahi_client_set_errno (client, AVAHI_ERR_NO_MEMORY);
 425             goto fail;
 426         }
 427     }
 428
 429     reply = dbus_connection_send_with_reply_and_block (client->bus, message, -1, &error);
 430
 431     if (!reply || dbus_error_is_set (&error))
 432         goto fail;
 433
 434     if (!dbus_message_get_args (reply, &error, DBUS_TYPE_STRING, &ret, DBUS_TYPE_INVALID) ||
 435         dbus_error_is_set (&error))
 436         goto fail;
 437
 438     if (!(n = avahi_strdup(ret))) {
 439         avahi_client_set_errno(client, AVAHI_ERR_NO_MEMORY);
 440         goto fail;
 441     }
 442
 443     dbus_message_unref(message);
 444     dbus_message_unref(reply);
 445
 446     return n;
 447
 448 fail:
 449
 450     if (message)
 451         dbus_message_unref(message);
 452     if (reply)
 453         dbus_message_unref(reply);
 454
 455     if (dbus_error_is_set(&error)) {
 456         avahi_client_set_dbus_error(client, &error);
 457         dbus_error_free(&error);
 458     }
 459
 460     return NULL;
 461 }
 462
 463 const char* avahi_client_get_version_string (AvahiClient *client) {
 464     assert(client);
 465
 466     if (client->state == AVAHI_CLIENT_DISCONNECTED) {
 467         avahi_client_set_errno(client, AVAHI_ERR_BAD_STATE);
 468         return NULL;
 469     }
 470
 471     if (!client->version_string)
 472         client->version_string = avahi_client_get_string_reply_and_block(client, "GetVersionString", NULL);
 473
 474     return client->version_string;
 475 }
 476
 477 const char* avahi_client_get_domain_name (AvahiClient *client) {
 478     assert(client);
 479
 480     if (client->state == AVAHI_CLIENT_DISCONNECTED) {
 481         avahi_client_set_errno(client, AVAHI_ERR_BAD_STATE);
 482         return NULL;
 483     }
 484
 485     if (!client->domain_name)
 486         client->domain_name = avahi_client_get_string_reply_and_block(client, "GetDomainName", NULL);
 487
 488     return client->domain_name;
 489 }
 490
 491 const char* avahi_client_get_host_name (AvahiClient *client) {
 492     assert(client);
 493
 494     if (client->state == AVAHI_CLIENT_DISCONNECTED) {
 495         avahi_client_set_errno(client, AVAHI_ERR_BAD_STATE);
 496         return NULL;
 497     }
 498
 499     if (!client->host_name)
 500         client->host_name = avahi_client_get_string_reply_and_block(client, "GetHostName", NULL);
 501
 502     return client->host_name;
 503 }
 504
 505 const char* avahi_client_get_host_name_fqdn (AvahiClient *client) {
 506     assert(client);
 507
 508     if (client->state == AVAHI_CLIENT_DISCONNECTED) {
 509         avahi_client_set_errno(client, AVAHI_ERR_BAD_STATE);
 510         return NULL;
 511     }
 512
 513     if (!client->host_name_fqdn)
 514         client->host_name_fqdn = avahi_client_get_string_reply_and_block(client, "GetHostNameFqdn", NULL);
 515
 516     return client->host_name_fqdn;
 517 }
 518
 519 AvahiClientState avahi_client_get_state(AvahiClient *client) {
 520     assert(client);
 521
 522     return client->state;
 523 }
 524
 525 int avahi_client_errno(AvahiClient *client) {
 526     assert(client);
 527
 528     return client->error;
 529 }