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   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 "announce.h"
  27 #include "util.h"
  28
  29 #define AVAHI_ANNOUNCEMENT_JITTER_MSEC 250
  30 #define AVAHI_PROBE_JITTER_MSEC 250
  31 #define AVAHI_PROBE_INTERVAL_MSEC 250
  32
  33 static void remove_announcement(AvahiServer *s, AvahiAnnouncement *a) {
  34     g_assert(s);
  35     g_assert(a);
  36
  37     if (a->time_event)
  38         avahi_time_event_queue_remove(s->time_event_queue, a->time_event);
  39
  40     AVAHI_LLIST_REMOVE(AvahiAnnouncement, by_interface, a->interface->announcements, a);
  41     AVAHI_LLIST_REMOVE(AvahiAnnouncement, by_entry, a->entry->announcements, a);
  42
  43     g_free(a);
  44 }
  45
  46 static void elapse_announce(AvahiTimeEvent *e, void *userdata);
  47
  48 static void set_timeout(AvahiAnnouncement *a, const GTimeVal *tv) {
  49     g_assert(a);
  50
  51     if (!tv) {
  52         if (a->time_event) {
  53             avahi_time_event_queue_remove(a->server->time_event_queue, a->time_event);
  54             a->time_event = NULL;
  55         }
  56     } else {
  57
  58         if (a->time_event)
  59             avahi_time_event_queue_update(a->server->time_event_queue, a->time_event, tv);
  60         else
  61             a->time_event = avahi_time_event_queue_add(a->server->time_event_queue, tv, elapse_announce, a);
  62     }
  63 }
  64
  65 static void next_state(AvahiAnnouncement *a);
  66
  67 void avahi_entry_group_check_probed(AvahiEntryGroup *g, gboolean immediately) {
  68     AvahiEntry *e;
  69     g_assert(g);
  70     g_assert(!g->dead);
  71
  72     /* Check whether all group members have been probed */
  73
  74     if (g->state != AVAHI_ENTRY_GROUP_REGISTERING || g->n_probing > 0)
  75         return;
  76
  77     avahi_entry_group_change_state(g, AVAHI_ENTRY_GROUP_ESTABLISHED);
  78
  79     if (g->dead)
  80         return;
  81
  82     for (e = g->entries; e; e = e->entries_next) {
  83         AvahiAnnouncement *a;
  84
  85         for (a = e->announcements; a; a = a->by_entry_next) {
  86
  87             if (a->state != AVAHI_WAITING)
  88                 continue;
  89
  90             a->state = AVAHI_ANNOUNCING;
  91
  92             if (immediately) {
  93                 /* Shortcut */
  94
  95                 a->n_iteration = 1;
  96                 next_state(a);
  97             } else {
  98                 GTimeVal tv;
  99                 a->n_iteration = 0;
 100                 avahi_elapse_time(&tv, 0, AVAHI_ANNOUNCEMENT_JITTER_MSEC);
 101                 set_timeout(a, &tv);
 102             }
 103         }
 104     }
 105 }
 106
 107 static void next_state(AvahiAnnouncement *a) {
 108     g_assert(a);
 109
 110 /*     g_message("%i -- %u", a->state, a->n_iteration);   */
 111
 112     if (a->state == AVAHI_WAITING) {
 113
 114         g_assert(a->entry->group);
 115
 116         avahi_entry_group_check_probed(a->entry->group, TRUE);
 117
 118     } else if (a->state == AVAHI_PROBING) {
 119
 120         if (a->n_iteration >= 4) {
 121             /* Probing done */
 122
 123             gchar *t;
 124
 125             g_message("Enough probes for record [%s]", t = avahi_record_to_string(a->entry->record));
 126             g_free(t);
 127
 128             if (a->entry->group) {
 129                 g_assert(a->entry->group->n_probing);
 130                 a->entry->group->n_probing--;
 131             }
 132
 133             if (a->entry->group && a->entry->group->state == AVAHI_ENTRY_GROUP_REGISTERING)
 134                 a->state = AVAHI_WAITING;
 135             else {
 136                 a->state = AVAHI_ANNOUNCING;
 137                 a->n_iteration = 1;
 138             }
 139
 140             set_timeout(a, NULL);
 141             next_state(a);
 142         } else {
 143             GTimeVal tv;
 144
 145             avahi_interface_post_probe(a->interface, a->entry->record, FALSE);
 146
 147             avahi_elapse_time(&tv, AVAHI_PROBE_INTERVAL_MSEC, 0);
 148             set_timeout(a, &tv);
 149
 150             a->n_iteration++;
 151         }
 152
 153     } else if (a->state == AVAHI_ANNOUNCING) {
 154
 155         avahi_interface_post_response(a->interface, NULL, a->entry->record, a->entry->flags & AVAHI_ENTRY_UNIQUE, FALSE);
 156
 157         if (++a->n_iteration >= 4) {
 158             gchar *t;
 159             /* Announcing done */
 160
 161             g_message("Enough announcements for record [%s]", t = avahi_record_to_string(a->entry->record));
 162             g_free(t);
 163
 164             a->state = AVAHI_ESTABLISHED;
 165
 166             set_timeout(a, NULL);
 167         } else {
 168             GTimeVal tv;
 169             avahi_elapse_time(&tv, a->sec_delay*1000, AVAHI_ANNOUNCEMENT_JITTER_MSEC);
 170
 171             if (a->n_iteration < 10)
 172                 a->sec_delay *= 2;
 173
 174             set_timeout(a, &tv);
 175         }
 176     }
 177 }
 178
 179 static void elapse_announce(AvahiTimeEvent *e, void *userdata) {
 180     g_assert(e);
 181
 182     next_state(userdata);
 183 }
 184
 185 AvahiAnnouncement *avahi_get_announcement(AvahiServer *s, AvahiEntry *e, AvahiInterface *i) {
 186     AvahiAnnouncement *a;
 187
 188     g_assert(s);
 189     g_assert(e);
 190     g_assert(i);
 191
 192     for (a = e->announcements; a; a = a->by_entry_next)
 193         if (a->interface == i)
 194             return a;
 195
 196     return NULL;
 197 }
 198
 199 static void new_announcement(AvahiServer *s, AvahiInterface *i, AvahiEntry *e) {
 200     AvahiAnnouncement *a;
 201     GTimeVal tv;
 202     gchar *t;
 203
 204     g_assert(s);
 205     g_assert(i);
 206     g_assert(e);
 207     g_assert(!e->dead);
 208
 209 /*     g_message("NEW ANNOUNCEMENT: %s.%i [%s]", i->hardware->name, i->protocol, t = avahi_record_to_string(e->record)); */
 210 /*     g_free(t); */
 211
 212     if (!avahi_interface_match(i, e->interface, e->protocol) || !i->announcing || !avahi_entry_commited(e))
 213         return;
 214
 215     /* We don't want duplicate announcements */
 216     if (avahi_get_announcement(s, e, i))
 217         return;
 218
 219     a = g_new(AvahiAnnouncement, 1);
 220     a->server = s;
 221     a->interface = i;
 222     a->entry = e;
 223
 224     if ((e->flags & AVAHI_ENTRY_UNIQUE) && !(e->flags & AVAHI_ENTRY_NOPROBE))
 225         a->state = AVAHI_PROBING;
 226     else if (!(e->flags & AVAHI_ENTRY_NOANNOUNCE)) {
 227
 228         if (!e->group || e->group->state == AVAHI_ENTRY_GROUP_ESTABLISHED)
 229             a->state = AVAHI_ANNOUNCING;
 230         else
 231             a->state = AVAHI_WAITING;
 232
 233     } else
 234         a->state = AVAHI_ESTABLISHED;
 235
 236
 237     g_message("New announcement on interface %s.%i for entry [%s] state=%i", i->hardware->name, i->protocol, t = avahi_record_to_string(e->record), a->state);
 238     g_free(t);
 239
 240     a->n_iteration = 1;
 241     a->sec_delay = 1;
 242     a->time_event = NULL;
 243
 244     if (a->state == AVAHI_PROBING)
 245         if (e->group)
 246             e->group->n_probing++;
 247
 248     AVAHI_LLIST_PREPEND(AvahiAnnouncement, by_interface, i->announcements, a);
 249     AVAHI_LLIST_PREPEND(AvahiAnnouncement, by_entry, e->announcements, a);
 250
 251     if (a->state == AVAHI_PROBING) {
 252         avahi_elapse_time(&tv, 0, AVAHI_PROBE_JITTER_MSEC);
 253         set_timeout(a, &tv);
 254     } else if (a->state == AVAHI_ANNOUNCING) {
 255         avahi_elapse_time(&tv, 0, AVAHI_ANNOUNCEMENT_JITTER_MSEC);
 256         set_timeout(a, &tv);
 257     }
 258 }
 259
 260 void avahi_announce_interface(AvahiServer *s, AvahiInterface *i) {
 261     AvahiEntry *e;
 262
 263     g_assert(s);
 264     g_assert(i);
 265
 266     if (!i->announcing)
 267         return;
 268
 269     for (e = s->entries; e; e = e->entries_next)
 270         if (!e->dead)
 271             new_announcement(s, i, e);
 272 }
 273
 274 static void announce_walk_callback(AvahiInterfaceMonitor *m, AvahiInterface *i, gpointer userdata) {
 275     AvahiEntry *e = userdata;
 276
 277     g_assert(m);
 278     g_assert(i);
 279     g_assert(e);
 280     g_assert(!e->dead);
 281
 282     new_announcement(m->server, i, e);
 283 }
 284
 285 void avahi_announce_entry(AvahiServer *s, AvahiEntry *e) {
 286     g_assert(s);
 287     g_assert(e);
 288     g_assert(!e->dead);
 289
 290     avahi_interface_monitor_walk(s->monitor, e->interface, e->protocol, announce_walk_callback, e);
 291 }
 292
 293 void avahi_announce_group(AvahiServer *s, AvahiEntryGroup *g) {
 294     AvahiEntry *e;
 295
 296     g_assert(s);
 297     g_assert(g);
 298
 299     for (e = g->entries; e; e = e->by_group_next)
 300         if (!e->dead)
 301             avahi_announce_entry(s, e);
 302 }
 303
 304 gboolean avahi_entry_registered(AvahiServer *s, AvahiEntry *e, AvahiInterface *i) {
 305     AvahiAnnouncement *a;
 306
 307     g_assert(s);
 308     g_assert(e);
 309     g_assert(i);
 310     g_assert(!e->dead);
 311
 312     if (!(a = avahi_get_announcement(s, e, i)))
 313         return FALSE;
 314
 315     return a->state == AVAHI_ANNOUNCING || a->state == AVAHI_ESTABLISHED;
 316 }
 317
 318 gboolean avahi_entry_registering(AvahiServer *s, AvahiEntry *e, AvahiInterface *i) {
 319     AvahiAnnouncement *a;
 320
 321     g_assert(s);
 322     g_assert(e);
 323     g_assert(i);
 324     g_assert(!e->dead);
 325
 326     if (!(a = avahi_get_announcement(s, e, i)))
 327         return FALSE;
 328
 329     return a->state == AVAHI_PROBING || a->state == AVAHI_WAITING;
 330 }
 331
 332 static AvahiRecord *make_goodbye_record(AvahiRecord *r) {
 333 /*     gchar *t; */
 334     AvahiRecord *g;
 335
 336     g_assert(r);
 337
 338 /*     g_message("Preparing goodbye for record [%s]", t = avahi_record_to_string(r)); */
 339 /*     g_free(t); */
 340
 341     g = avahi_record_copy(r);
 342     g_assert(g->ref == 1);
 343     g->ttl = 0;
 344
 345     return g;
 346 }
 347
 348 static void send_goodbye_callback(AvahiInterfaceMonitor *m, AvahiInterface *i, gpointer userdata) {
 349     AvahiEntry *e = userdata;
 350     AvahiRecord *g;
 351
 352     g_assert(m);
 353     g_assert(i);
 354     g_assert(e);
 355     g_assert(!e->dead);
 356
 357     if (!avahi_interface_match(i, e->interface, e->protocol))
 358         return;
 359
 360     if (e->flags & AVAHI_ENTRY_NOANNOUNCE)
 361         return;
 362
 363     if (!avahi_entry_registered(m->server, e, i))
 364         return;
 365
 366     g = make_goodbye_record(e->record);
 367     avahi_interface_post_response(i, NULL, g, e->flags & AVAHI_ENTRY_UNIQUE, TRUE);
 368     avahi_record_unref(g);
 369 }
 370
 371 void avahi_goodbye_interface(AvahiServer *s, AvahiInterface *i, gboolean goodbye) {
 372     g_assert(s);
 373     g_assert(i);
 374
 375 /*     g_message("goodbye interface: %s.%u", i->hardware->name, i->protocol); */
 376
 377     if (goodbye && avahi_interface_relevant(i)) {
 378         AvahiEntry *e;
 379
 380         for (e = s->entries; e; e = e->entries_next)
 381             if (!e->dead)
 382                 send_goodbye_callback(s->monitor, i, e);
 383     }
 384
 385     while (i->announcements)
 386         remove_announcement(s, i->announcements);
 387
 388 /*     g_message("goodbye interface done: %s.%u", i->hardware->name, i->protocol); */
 389
 390 }
 391
 392 void avahi_goodbye_entry(AvahiServer *s, AvahiEntry *e, gboolean goodbye) {
 393     g_assert(s);
 394     g_assert(e);
 395
 396 /*     g_message("goodbye entry: %p", e); */
 397
 398     if (goodbye && !e->dead)
 399         avahi_interface_monitor_walk(s->monitor, 0, AF_UNSPEC, send_goodbye_callback, e);
 400
 401     while (e->announcements)
 402         remove_announcement(s, e->announcements);
 403
 404 /*     g_message("goodbye entry done: %p", e); */
 405
 406 }
 407
 408 void avahi_goodbye_all(AvahiServer *s, gboolean goodbye) {
 409     AvahiEntry *e;
 410
 411     g_assert(s);
 412
 413 /*     g_message("goodbye all"); */
 414
 415     for (e = s->entries; e; e = e->entries_next)
 416         if (!e->dead)
 417             avahi_goodbye_entry(s, e, goodbye);
 418
 419 /*     g_message("goodbye all done"); */
 420
 421 }
 422