diff options
Diffstat (limited to 'src/resolve/resolved-mdns.c')
| -rw-r--r-- | src/resolve/resolved-mdns.c | 43 |
1 files changed, 43 insertions, 0 deletions
diff --git a/src/resolve/resolved-mdns.c b/src/resolve/resolved-mdns.c index 3e6e83f..8f93af3 100644 --- a/src/resolve/resolved-mdns.c +++ b/src/resolve/resolved-mdns.c @@ -349,6 +349,33 @@ static int mdns_scope_process_query(DnsScope *s, DnsPacket *p) { return 0; } +static int mdns_goodbye_callback(sd_event_source *s, uint64_t usec, void *userdata) { + DnsScope *scope = userdata; + int r; + + assert(s); + assert(scope); + + scope->mdns_goodbye_event_source = sd_event_source_disable_unref(scope->mdns_goodbye_event_source); + + dns_cache_prune(&scope->cache); + + if (dns_cache_expiry_in_one_second(&scope->cache, usec)) { + r = sd_event_add_time_relative( + scope->manager->event, + &scope->mdns_goodbye_event_source, + CLOCK_BOOTTIME, + USEC_PER_SEC, + 0, + mdns_goodbye_callback, + scope); + if (r < 0) + return log_error_errno(r, "mDNS: Failed to re-schedule goodbye callback: %m"); + } + + return 0; +} + static int on_mdns_packet(sd_event_source *s, int fd, uint32_t revents, void *userdata) { _cleanup_(dns_packet_unrefp) DnsPacket *p = NULL; Manager *m = userdata; @@ -407,6 +434,22 @@ static int on_mdns_packet(sd_event_source *s, int fd, uint32_t revents, void *us log_debug("Got a goodbye packet"); /* See the section 10.1 of RFC6762 */ rr->ttl = 1; + + /* Look at the cache 1 second later and remove stale entries. + * This is particularly useful to keep service browsers updated on service removal, + * as there are no other reliable triggers to propagate that info. */ + if (!scope->mdns_goodbye_event_source) { + r = sd_event_add_time_relative( + scope->manager->event, + &scope->mdns_goodbye_event_source, + CLOCK_BOOTTIME, + USEC_PER_SEC, + 0, + mdns_goodbye_callback, + scope); + if (r < 0) + return r; + } } } |