| /*** |
| This file is part of avahi. |
| |
| avahi is free software; you can redistribute it and/or modify it |
| under the terms of the GNU Lesser General Public License as |
| published by the Free Software Foundation; either version 2.1 of the |
| License, or (at your option) any later version. |
| |
| avahi is distributed in the hope that it will be useful, but WITHOUT |
| ANY WARRANTY; without even the implied warranty of MERCHANTABILITY |
| or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General |
| Public License for more details. |
| |
| You should have received a copy of the GNU Lesser General Public |
| License along with avahi; if not, write to the Free Software |
| Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 |
| USA. |
| ***/ |
| |
| #ifdef HAVE_CONFIG_H |
| #include <config.h> |
| #endif |
| |
| #include <stdlib.h> |
| |
| #include <avahi-common/timeval.h> |
| #include <avahi-common/malloc.h> |
| #include <avahi-common/error.h> |
| #include <avahi-common/domain.h> |
| |
| #include "browse.h" |
| |
| #define TIMEOUT_MSEC 5000 |
| |
| struct AvahiSAddressResolver { |
| AvahiServer *server; |
| AvahiAddress address; |
| |
| AvahiSRecordBrowser *record_browser; |
| |
| AvahiSAddressResolverCallback callback; |
| void* userdata; |
| |
| AvahiRecord *ptr_record; |
| AvahiIfIndex interface; |
| AvahiProtocol protocol; |
| AvahiLookupResultFlags flags; |
| |
| int retry_with_multicast; |
| AvahiKey *key; |
| |
| AvahiTimeEvent *time_event; |
| |
| AVAHI_LLIST_FIELDS(AvahiSAddressResolver, resolver); |
| }; |
| |
| static void finish(AvahiSAddressResolver *r, AvahiResolverEvent event) { |
| assert(r); |
| |
| if (r->time_event) { |
| avahi_time_event_free(r->time_event); |
| r->time_event = NULL; |
| } |
| |
| switch (event) { |
| case AVAHI_RESOLVER_FAILURE: |
| r->callback(r, r->interface, r->protocol, event, &r->address, NULL, r->flags, r->userdata); |
| break; |
| |
| case AVAHI_RESOLVER_FOUND: |
| assert(r->ptr_record); |
| r->callback(r, r->interface, r->protocol, event, &r->address, r->ptr_record->data.ptr.name, r->flags, r->userdata); |
| break; |
| } |
| } |
| |
| static void time_event_callback(AvahiTimeEvent *e, void *userdata) { |
| AvahiSAddressResolver *r = userdata; |
| |
| assert(e); |
| assert(r); |
| |
| avahi_server_set_errno(r->server, AVAHI_ERR_TIMEOUT); |
| finish(r, AVAHI_RESOLVER_FAILURE); |
| } |
| |
| static void start_timeout(AvahiSAddressResolver *r) { |
| struct timeval tv; |
| assert(r); |
| |
| if (r->time_event) |
| return; |
| |
| avahi_elapse_time(&tv, TIMEOUT_MSEC, 0); |
| r->time_event = avahi_time_event_new(r->server->time_event_queue, &tv, time_event_callback, r); |
| } |
| |
| static void record_browser_callback( |
| AvahiSRecordBrowser*rr, |
| AvahiIfIndex interface, |
| AvahiProtocol protocol, |
| AvahiBrowserEvent event, |
| AvahiRecord *record, |
| AvahiLookupResultFlags flags, |
| void* userdata) { |
| |
| AvahiSAddressResolver *r = userdata; |
| |
| assert(rr); |
| assert(r); |
| |
| switch (event) { |
| case AVAHI_BROWSER_NEW: |
| assert(record); |
| assert(record->key->type == AVAHI_DNS_TYPE_PTR); |
| |
| if (r->interface > 0 && interface != r->interface) |
| return; |
| |
| if (r->protocol != AVAHI_PROTO_UNSPEC && protocol != r->protocol) |
| return; |
| |
| if (r->interface <= 0) |
| r->interface = interface; |
| |
| if (r->protocol == AVAHI_PROTO_UNSPEC) |
| r->protocol = protocol; |
| |
| if (!r->ptr_record) { |
| r->ptr_record = avahi_record_ref(record); |
| r->flags = flags; |
| |
| finish(r, AVAHI_RESOLVER_FOUND); |
| } |
| break; |
| |
| case AVAHI_BROWSER_REMOVE: |
| assert(record); |
| assert(record->key->type == AVAHI_DNS_TYPE_PTR); |
| |
| if (r->ptr_record && avahi_record_equal_no_ttl(record, r->ptr_record)) { |
| avahi_record_unref(r->ptr_record); |
| r->ptr_record = NULL; |
| r->flags = flags; |
| |
| /** Look for a replacement */ |
| avahi_s_record_browser_restart(r->record_browser); |
| start_timeout(r); |
| } |
| |
| break; |
| |
| case AVAHI_BROWSER_CACHE_EXHAUSTED: |
| case AVAHI_BROWSER_ALL_FOR_NOW: |
| break; |
| |
| case AVAHI_BROWSER_FAILURE: |
| |
| if (r->retry_with_multicast) { |
| r->retry_with_multicast = 0; |
| |
| avahi_s_record_browser_free(r->record_browser); |
| r->record_browser = avahi_s_record_browser_new(r->server, r->interface, r->protocol, r->key, AVAHI_LOOKUP_USE_MULTICAST, record_browser_callback, r); |
| |
| if (r->record_browser) { |
| start_timeout(r); |
| break; |
| } |
| } |
| |
| r->flags = flags; |
| finish(r, AVAHI_RESOLVER_FAILURE); |
| break; |
| } |
| } |
| |
| AvahiSAddressResolver *avahi_s_address_resolver_new( |
| AvahiServer *server, |
| AvahiIfIndex interface, |
| AvahiProtocol protocol, |
| const AvahiAddress *address, |
| AvahiLookupFlags flags, |
| AvahiSAddressResolverCallback callback, |
| void* userdata) { |
| |
| AvahiSAddressResolver *r; |
| AvahiKey *k; |
| char n[AVAHI_DOMAIN_NAME_MAX]; |
| |
| assert(server); |
| assert(address); |
| assert(callback); |
| |
| AVAHI_CHECK_VALIDITY_RETURN_NULL(server, AVAHI_IF_VALID(interface), AVAHI_ERR_INVALID_INTERFACE); |
| AVAHI_CHECK_VALIDITY_RETURN_NULL(server, AVAHI_PROTO_VALID(protocol), AVAHI_ERR_INVALID_PROTOCOL); |
| AVAHI_CHECK_VALIDITY_RETURN_NULL(server, address->proto == AVAHI_PROTO_INET || address->proto == AVAHI_PROTO_INET6, AVAHI_ERR_INVALID_PROTOCOL); |
| AVAHI_CHECK_VALIDITY_RETURN_NULL(server, AVAHI_FLAGS_VALID(flags, AVAHI_LOOKUP_USE_WIDE_AREA|AVAHI_LOOKUP_USE_MULTICAST), AVAHI_ERR_INVALID_FLAGS); |
| |
| avahi_reverse_lookup_name(address, n, sizeof(n)); |
| |
| if (!(k = avahi_key_new(n, AVAHI_DNS_CLASS_IN, AVAHI_DNS_TYPE_PTR))) { |
| avahi_server_set_errno(server, AVAHI_ERR_NO_MEMORY); |
| return NULL; |
| } |
| |
| if (!(r = avahi_new(AvahiSAddressResolver, 1))) { |
| avahi_server_set_errno(server, AVAHI_ERR_NO_MEMORY); |
| avahi_key_unref(k); |
| return NULL; |
| } |
| |
| r->server = server; |
| r->address = *address; |
| r->callback = callback; |
| r->userdata = userdata; |
| r->ptr_record = NULL; |
| r->interface = interface; |
| r->protocol = protocol; |
| r->flags = 0; |
| r->retry_with_multicast = 0; |
| r->key = k; |
| |
| r->record_browser = NULL; |
| AVAHI_LLIST_PREPEND(AvahiSAddressResolver, resolver, server->address_resolvers, r); |
| |
| r->time_event = NULL; |
| |
| if (!(flags & (AVAHI_LOOKUP_USE_MULTICAST|AVAHI_LOOKUP_USE_WIDE_AREA))) { |
| |
| if (!server->wide_area_lookup_engine || !avahi_wide_area_has_servers(server->wide_area_lookup_engine)) |
| flags |= AVAHI_LOOKUP_USE_MULTICAST; |
| else { |
| flags |= AVAHI_LOOKUP_USE_WIDE_AREA; |
| r->retry_with_multicast = 1; |
| } |
| } |
| |
| r->record_browser = avahi_s_record_browser_new(server, interface, protocol, k, flags, record_browser_callback, r); |
| |
| if (!r->record_browser) { |
| avahi_s_address_resolver_free(r); |
| return NULL; |
| } |
| |
| start_timeout(r); |
| |
| return r; |
| } |
| |
| void avahi_s_address_resolver_free(AvahiSAddressResolver *r) { |
| assert(r); |
| |
| AVAHI_LLIST_REMOVE(AvahiSAddressResolver, resolver, r->server->address_resolvers, r); |
| |
| if (r->record_browser) |
| avahi_s_record_browser_free(r->record_browser); |
| |
| if (r->time_event) |
| avahi_time_event_free(r->time_event); |
| |
| if (r->ptr_record) |
| avahi_record_unref(r->ptr_record); |
| |
| if (r->key) |
| avahi_key_unref(r->key); |
| |
| avahi_free(r); |
| } |
