git.meshlink.io Git - catta/blob - libavahi-core/subscribe.c

   1 #include "subscribe.h"
   2 #include "util.h"
   3
   4 static void elapse(AvahiTimeEvent *e, void *userdata) {
   5     AvahiSubscription *s = userdata;
   6     GTimeVal tv;
   7     gchar *t;
   8
   9     g_assert(s);
  10
  11     avahi_server_post_query(s->server, s->interface, s->protocol, s->key);
  12
  13     if (s->n_query++ <= 8)
  14         s->sec_delay *= 2;
  15
  16     g_message("%i. Continuous querying for %s", s->n_query, t = avahi_key_to_string(s->key));
  17     g_free(t);
  18
  19     avahi_elapse_time(&tv, s->sec_delay*1000, 0);
  20     avahi_time_event_queue_update(s->server->time_event_queue, s->time_event, &tv);
  21 }
  22
  23 struct cbdata {
  24     AvahiSubscription *subscription;
  25     AvahiInterface *interface;
  26 };
  27
  28 static gpointer scan_cache_callback(AvahiCache *c, AvahiKey *pattern, AvahiCacheEntry *e, gpointer userdata) {
  29     struct cbdata *cbdata = userdata;
  30
  31     g_assert(c);
  32     g_assert(pattern);
  33     g_assert(e);
  34     g_assert(cbdata);
  35
  36     cbdata->subscription->callback(
  37         cbdata->subscription,
  38         e->record,
  39         cbdata->interface->hardware->index,
  40         cbdata->interface->protocol,
  41         AVAHI_SUBSCRIPTION_NEW,
  42         cbdata->subscription->userdata);
  43
  44     return NULL;
  45 }
  46
  47 static void scan_interface_callback(AvahiInterfaceMonitor *m, AvahiInterface *i, gpointer userdata) {
  48     AvahiSubscription *s = userdata;
  49     struct cbdata cbdata = { s, i };
  50
  51     g_assert(m);
  52     g_assert(i);
  53     g_assert(s);
  54
  55     avahi_cache_walk(i->cache, s->key, scan_cache_callback, &cbdata);
  56 }
  57
  58 AvahiSubscription *avahi_subscription_new(AvahiServer *server, AvahiKey *key, gint interface, guchar protocol, AvahiSubscriptionCallback callback, gpointer userdata) {
  59     AvahiSubscription *s, *t;
  60     GTimeVal tv;
  61
  62     g_assert(server);
  63     g_assert(key);
  64     g_assert(callback);
  65
  66     g_assert(!avahi_key_is_pattern(key));
  67
  68     s = g_new(AvahiSubscription, 1);
  69     s->server = server;
  70     s->key = avahi_key_ref(key);
  71     s->interface = interface;
  72     s->protocol = protocol;
  73     s->callback = callback;
  74     s->userdata = userdata;
  75     s->n_query = 1;
  76     s->sec_delay = 1;
  77
  78     avahi_server_post_query(s->server, s->interface, s->protocol, s->key);
  79
  80     avahi_elapse_time(&tv, s->sec_delay*1000, 0);
  81     s->time_event = avahi_time_event_queue_add(server->time_event_queue, &tv, elapse, s);
  82
  83     AVAHI_LLIST_PREPEND(AvahiSubscription, subscriptions, server->subscriptions, s);
  84
  85     /* Add the new entry to the subscription hash table */
  86     t = g_hash_table_lookup(server->subscription_hashtable, key);
  87     AVAHI_LLIST_PREPEND(AvahiSubscription, by_key, t, s);
  88     g_hash_table_replace(server->subscription_hashtable, key, t);
  89
  90     /* Scan the caches */
  91     avahi_interface_monitor_walk(s->server->monitor, s->interface, s->protocol, scan_interface_callback, s);
  92
  93     return s;
  94 }
  95
  96 void avahi_subscription_free(AvahiSubscription *s) {
  97     AvahiSubscription *t;
  98
  99     g_assert(s);
 100
 101     AVAHI_LLIST_REMOVE(AvahiSubscription, subscriptions, s->server->subscriptions, s);
 102
 103     t = g_hash_table_lookup(s->server->subscription_hashtable, s->key);
 104     AVAHI_LLIST_REMOVE(AvahiSubscription, by_key, t, s);
 105     if (t)
 106         g_hash_table_replace(s->server->subscription_hashtable, t->key, t);
 107     else
 108         g_hash_table_remove(s->server->subscription_hashtable, s->key);
 109
 110     avahi_time_event_queue_remove(s->server->time_event_queue, s->time_event);
 111     avahi_key_unref(s->key);
 112
 113
 114     g_free(s);
 115 }
 116
 117 void avahi_subscription_notify(AvahiServer *server, AvahiInterface *i, AvahiRecord *record, AvahiSubscriptionEvent event) {
 118     AvahiSubscription *s;
 119     AvahiKey *pattern;
 120
 121     g_assert(server);
 122     g_assert(record);
 123
 124     for (s = g_hash_table_lookup(server->subscription_hashtable, record->key); s; s = s->by_key_next)
 125         if (avahi_interface_match(i, s->interface, s->protocol))
 126             s->callback(s, record, i->hardware->index, i->protocol, event, s->userdata);
 127 }
 128
 129 gboolean avahi_is_subscribed(AvahiServer *server, AvahiKey *k) {
 130     g_assert(server);
 131     g_assert(k);
 132
 133     return !!g_hash_table_lookup(server->subscription_hashtable, k);
 134 }