git.meshlink.io Git - catta/blob - libavahi-core/announce.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 #include "announce.h"
  23 #include "util.h"
  24
  25 #define AVAHI_ANNOUNCEMENT_JITTER_MSEC 250
  26 #define AVAHI_PROBE_JITTER_MSEC 250
  27 #define AVAHI_PROBE_INTERVAL_MSEC 250
  28
  29 static void remove_announcement(AvahiServer *s, AvahiAnnouncement *a) {
  30     g_assert(s);
  31     g_assert(a);
  32
  33     if (a->time_event)
  34         avahi_time_event_queue_remove(s->time_event_queue, a->time_event);
  35
  36     AVAHI_LLIST_REMOVE(AvahiAnnouncement, by_interface, a->interface->announcements, a);
  37     AVAHI_LLIST_REMOVE(AvahiAnnouncement, by_entry, a->entry->announcements, a);
  38
  39     g_free(a);
  40 }
  41
  42 static void elapse_announce(AvahiTimeEvent *e, void *userdata);
  43
  44 static void set_timeout(AvahiAnnouncement *a, const GTimeVal *tv) {
  45     g_assert(a);
  46
  47     if (!tv) {
  48         if (a->time_event) {
  49             avahi_time_event_queue_remove(a->server->time_event_queue, a->time_event);
  50             a->time_event = NULL;
  51         }
  52     } else {
  53
  54         if (a->time_event)
  55             avahi_time_event_queue_update(a->server->time_event_queue, a->time_event, tv);
  56         else
  57             a->time_event = avahi_time_event_queue_add(a->server->time_event_queue, tv, elapse_announce, a);
  58     }
  59 }
  60
  61 static void next_state(AvahiAnnouncement *a);
  62
  63 void avahi_entry_group_check_probed(AvahiEntryGroup *g, gboolean immediately) {
  64     AvahiEntry *e;
  65     g_assert(g);
  66     g_assert(!g->dead);
  67
  68     /* Check whether all group members have been probed */
  69
  70     if (g->state != AVAHI_ENTRY_GROUP_REGISTERING || g->n_probing > 0)
  71         return;
  72
  73     avahi_entry_group_change_state(g, AVAHI_ENTRY_GROUP_ESTABLISHED);
  74
  75     if (g->dead)
  76         return;
  77
  78     for (e = g->entries; e; e = e->entries_next) {
  79         AvahiAnnouncement *a;
  80
  81         for (a = e->announcements; a; a = a->by_entry_next) {
  82
  83             if (a->state != AVAHI_WAITING)
  84                 continue;
  85
  86             a->state = AVAHI_ANNOUNCING;
  87
  88             if (immediately) {
  89                 /* Shortcut */
  90
  91                 a->n_iteration = 1;
  92                 next_state(a);
  93             } else {
  94                 GTimeVal tv;
  95                 a->n_iteration = 0;
  96                 avahi_elapse_time(&tv, 0, AVAHI_ANNOUNCEMENT_JITTER_MSEC);
  97                 set_timeout(a, &tv);
  98             }
  99         }
 100     }
 101 }
 102
 103 static void next_state(AvahiAnnouncement *a) {
 104     g_assert(a);
 105
 106 /*     g_message("%i -- %u", a->state, a->n_iteration);   */
 107
 108     if (a->state == AVAHI_WAITING) {
 109
 110         g_assert(a->entry->group);
 111
 112         avahi_entry_group_check_probed(a->entry->group, TRUE);
 113
 114     } else if (a->state == AVAHI_PROBING) {
 115
 116         if (a->n_iteration >= 4) {
 117             /* Probing done */
 118
 119             gchar *t;
 120
 121             g_message("Enough probes for record [%s]", t = avahi_record_to_string(a->entry->record));
 122             g_free(t);
 123
 124             if (a->entry->group) {
 125                 g_assert(a->entry->group->n_probing);
 126                 a->entry->group->n_probing--;
 127             }
 128
 129             if (a->entry->group && a->entry->group->state == AVAHI_ENTRY_GROUP_REGISTERING)
 130                 a->state = AVAHI_WAITING;
 131             else {
 132                 a->state = AVAHI_ANNOUNCING;
 133                 a->n_iteration = 1;
 134             }
 135
 136             set_timeout(a, NULL);
 137             next_state(a);
 138         } else {
 139             GTimeVal tv;
 140
 141             avahi_interface_post_probe(a->interface, a->entry->record, FALSE);
 142
 143             avahi_elapse_time(&tv, AVAHI_PROBE_INTERVAL_MSEC, 0);
 144             set_timeout(a, &tv);
 145
 146             a->n_iteration++;
 147         }
 148
 149     } else if (a->state == AVAHI_ANNOUNCING) {
 150
 151         avahi_interface_post_response(a->interface, NULL, a->entry->record, a->entry->flags & AVAHI_ENTRY_UNIQUE, FALSE);
 152
 153         if (++a->n_iteration >= 4) {
 154             gchar *t;
 155             /* Announcing done */
 156
 157             g_message("Enough announcements for record [%s]", t = avahi_record_to_string(a->entry->record));
 158             g_free(t);
 159
 160             a->state = AVAHI_ESTABLISHED;
 161
 162             set_timeout(a, NULL);
 163         } else {
 164             GTimeVal tv;
 165             avahi_elapse_time(&tv, a->sec_delay*1000, AVAHI_ANNOUNCEMENT_JITTER_MSEC);
 166
 167             if (a->n_iteration < 10)
 168                 a->sec_delay *= 2;
 169
 170             set_timeout(a, &tv);
 171         }
 172     }
 173 }
 174
 175 static void elapse_announce(AvahiTimeEvent *e, void *userdata) {
 176     g_assert(e);
 177
 178     next_state(userdata);
 179 }
 180
 181 AvahiAnnouncement *avahi_get_announcement(AvahiServer *s, AvahiEntry *e, AvahiInterface *i) {
 182     AvahiAnnouncement *a;
 183
 184     g_assert(s);
 185     g_assert(e);
 186     g_assert(i);
 187
 188     for (a = e->announcements; a; a = a->by_entry_next)
 189         if (a->interface == i)
 190             return a;
 191
 192     return NULL;
 193 }
 194
 195 static void new_announcement(AvahiServer *s, AvahiInterface *i, AvahiEntry *e) {
 196     AvahiAnnouncement *a;
 197     GTimeVal tv;
 198     gchar *t;
 199
 200     g_assert(s);
 201     g_assert(i);
 202     g_assert(e);
 203     g_assert(!e->dead);
 204
 205 /*     g_message("NEW ANNOUNCEMENT: %s.%i [%s]", i->hardware->name, i->protocol, t = avahi_record_to_string(e->record)); */
 206 /*     g_free(t); */
 207
 208     if (!avahi_interface_match(i, e->interface, e->protocol) || !i->announcing || !avahi_entry_commited(e))
 209         return;
 210
 211     /* We don't want duplicate announcements */
 212     if (avahi_get_announcement(s, e, i))
 213         return;
 214
 215     a = g_new(AvahiAnnouncement, 1);
 216     a->server = s;
 217     a->interface = i;
 218     a->entry = e;
 219
 220     if ((e->flags & AVAHI_ENTRY_UNIQUE) && !(e->flags & AVAHI_ENTRY_NOPROBE))
 221         a->state = AVAHI_PROBING;
 222     else if (!(e->flags & AVAHI_ENTRY_NOANNOUNCE)) {
 223
 224         if (!e->group || e->group->state == AVAHI_ENTRY_GROUP_ESTABLISHED)
 225             a->state = AVAHI_ANNOUNCING;
 226         else
 227             a->state = AVAHI_WAITING;
 228
 229     } else
 230         a->state = AVAHI_ESTABLISHED;
 231
 232
 233     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);
 234     g_free(t);
 235
 236     a->n_iteration = 1;
 237     a->sec_delay = 1;
 238     a->time_event = NULL;
 239
 240     if (a->state == AVAHI_PROBING)
 241         if (e->group)
 242             e->group->n_probing++;
 243
 244     AVAHI_LLIST_PREPEND(AvahiAnnouncement, by_interface, i->announcements, a);
 245     AVAHI_LLIST_PREPEND(AvahiAnnouncement, by_entry, e->announcements, a);
 246
 247     if (a->state == AVAHI_PROBING) {
 248         avahi_elapse_time(&tv, 0, AVAHI_PROBE_JITTER_MSEC);
 249         set_timeout(a, &tv);
 250     } else if (a->state == AVAHI_ANNOUNCING) {
 251         avahi_elapse_time(&tv, 0, AVAHI_ANNOUNCEMENT_JITTER_MSEC);
 252         set_timeout(a, &tv);
 253     }
 254 }
 255
 256 void avahi_announce_interface(AvahiServer *s, AvahiInterface *i) {
 257     AvahiEntry *e;
 258
 259     g_assert(s);
 260     g_assert(i);
 261
 262     if (!i->announcing)
 263         return;
 264
 265     for (e = s->entries; e; e = e->entries_next)
 266         if (!e->dead)
 267             new_announcement(s, i, e);
 268 }
 269
 270 static void announce_walk_callback(AvahiInterfaceMonitor *m, AvahiInterface *i, gpointer userdata) {
 271     AvahiEntry *e = userdata;
 272
 273     g_assert(m);
 274     g_assert(i);
 275     g_assert(e);
 276     g_assert(!e->dead);
 277
 278     new_announcement(m->server, i, e);
 279 }
 280
 281 void avahi_announce_entry(AvahiServer *s, AvahiEntry *e) {
 282     g_assert(s);
 283     g_assert(e);
 284     g_assert(!e->dead);
 285
 286     avahi_interface_monitor_walk(s->monitor, e->interface, e->protocol, announce_walk_callback, e);
 287 }
 288
 289 void avahi_announce_group(AvahiServer *s, AvahiEntryGroup *g) {
 290     AvahiEntry *e;
 291
 292     g_assert(s);
 293     g_assert(g);
 294
 295     for (e = g->entries; e; e = e->by_group_next)
 296         if (!e->dead)
 297             avahi_announce_entry(s, e);
 298 }
 299
 300 gboolean avahi_entry_registered(AvahiServer *s, AvahiEntry *e, AvahiInterface *i) {
 301     AvahiAnnouncement *a;
 302
 303     g_assert(s);
 304     g_assert(e);
 305     g_assert(i);
 306     g_assert(!e->dead);
 307
 308     if (!(a = avahi_get_announcement(s, e, i)))
 309         return FALSE;
 310
 311     return a->state == AVAHI_ANNOUNCING || a->state == AVAHI_ESTABLISHED;
 312 }
 313
 314 gboolean avahi_entry_registering(AvahiServer *s, AvahiEntry *e, AvahiInterface *i) {
 315     AvahiAnnouncement *a;
 316
 317     g_assert(s);
 318     g_assert(e);
 319     g_assert(i);
 320     g_assert(!e->dead);
 321
 322     if (!(a = avahi_get_announcement(s, e, i)))
 323         return FALSE;
 324
 325     return a->state == AVAHI_PROBING || a->state == AVAHI_WAITING;
 326 }
 327
 328 static AvahiRecord *make_goodbye_record(AvahiRecord *r) {
 329 /*     gchar *t; */
 330     AvahiRecord *g;
 331
 332     g_assert(r);
 333
 334 /*     g_message("Preparing goodbye for record [%s]", t = avahi_record_to_string(r)); */
 335 /*     g_free(t); */
 336
 337     g = avahi_record_copy(r);
 338     g_assert(g->ref == 1);
 339     g->ttl = 0;
 340
 341     return g;
 342 }
 343
 344 static void send_goodbye_callback(AvahiInterfaceMonitor *m, AvahiInterface *i, gpointer userdata) {
 345     AvahiEntry *e = userdata;
 346     AvahiRecord *g;
 347
 348     g_assert(m);
 349     g_assert(i);
 350     g_assert(e);
 351     g_assert(!e->dead);
 352
 353     if (!avahi_interface_match(i, e->interface, e->protocol))
 354         return;
 355
 356     if (e->flags & AVAHI_ENTRY_NOANNOUNCE)
 357         return;
 358
 359     if (!avahi_entry_registered(m->server, e, i))
 360         return;
 361
 362     g = make_goodbye_record(e->record);
 363     avahi_interface_post_response(i, NULL, g, e->flags & AVAHI_ENTRY_UNIQUE, TRUE);
 364     avahi_record_unref(g);
 365 }
 366
 367 void avahi_goodbye_interface(AvahiServer *s, AvahiInterface *i, gboolean goodbye) {
 368     g_assert(s);
 369     g_assert(i);
 370
 371 /*     g_message("goodbye interface: %s.%u", i->hardware->name, i->protocol); */
 372
 373     if (goodbye && avahi_interface_relevant(i)) {
 374         AvahiEntry *e;
 375
 376         for (e = s->entries; e; e = e->entries_next)
 377             if (!e->dead)
 378                 send_goodbye_callback(s->monitor, i, e);
 379     }
 380
 381     while (i->announcements)
 382         remove_announcement(s, i->announcements);
 383
 384 /*     g_message("goodbye interface done: %s.%u", i->hardware->name, i->protocol); */
 385
 386 }
 387
 388 void avahi_goodbye_entry(AvahiServer *s, AvahiEntry *e, gboolean goodbye) {
 389     g_assert(s);
 390     g_assert(e);
 391
 392 /*     g_message("goodbye entry: %p", e); */
 393
 394     if (goodbye && !e->dead)
 395         avahi_interface_monitor_walk(s->monitor, 0, AF_UNSPEC, send_goodbye_callback, e);
 396
 397     while (e->announcements)
 398         remove_announcement(s, e->announcements);
 399
 400 /*     g_message("goodbye entry done: %p", e); */
 401
 402 }
 403
 404 void avahi_goodbye_all(AvahiServer *s, gboolean goodbye) {
 405     AvahiEntry *e;
 406
 407     g_assert(s);
 408
 409 /*     g_message("goodbye all"); */
 410
 411     for (e = s->entries; e; e = e->entries_next)
 412         if (!e->dead)
 413             avahi_goodbye_entry(s, e, goodbye);
 414
 415 /*     g_message("goodbye all done"); */
 416
 417 }
 418