diff options
Diffstat (limited to 'trunk/avahi-core/browse.c')
| -rw-r--r-- | trunk/avahi-core/browse.c | 615 |
1 files changed, 0 insertions, 615 deletions
diff --git a/trunk/avahi-core/browse.c b/trunk/avahi-core/browse.c deleted file mode 100644 index 16d8954..0000000 --- a/trunk/avahi-core/browse.c +++ /dev/null @@ -1,615 +0,0 @@ -/* $Id$ */ - -/*** - 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 <avahi-common/rlist.h> -#include <avahi-common/address.h> - -#include "browse.h" -#include "log.h" -#include "querier.h" -#include "domain-util.h" -#include "rr-util.h" - -#define AVAHI_LOOKUPS_PER_BROWSER_MAX 15 - -struct AvahiSRBLookup { - AvahiSRecordBrowser *record_browser; - - unsigned ref; - - AvahiIfIndex interface; - AvahiProtocol protocol; - AvahiLookupFlags flags; - - AvahiKey *key; - - AvahiWideAreaLookup *wide_area; - AvahiMulticastLookup *multicast; - - AvahiRList *cname_lookups; - - AVAHI_LLIST_FIELDS(AvahiSRBLookup, lookups); -}; - -static void lookup_handle_cname(AvahiSRBLookup *l, AvahiIfIndex interface, AvahiProtocol protocol, AvahiLookupFlags flags, AvahiRecord *r); -static void lookup_drop_cname(AvahiSRBLookup *l, AvahiIfIndex interface, AvahiProtocol protocol, AvahiLookupFlags flags, AvahiRecord *r); - -static void transport_flags_from_domain(AvahiServer *s, AvahiLookupFlags *flags, const char *domain) { - assert(flags); - assert(domain); - - assert(!((*flags & AVAHI_LOOKUP_USE_MULTICAST) && (*flags & AVAHI_LOOKUP_USE_WIDE_AREA))); - - if (*flags & (AVAHI_LOOKUP_USE_MULTICAST|AVAHI_LOOKUP_USE_WIDE_AREA)) - return; - - if (!s->wide_area_lookup_engine || - !avahi_wide_area_has_servers(s->wide_area_lookup_engine) || - avahi_domain_ends_with(domain, AVAHI_MDNS_SUFFIX_LOCAL) || - avahi_domain_ends_with(domain, AVAHI_MDNS_SUFFIX_ADDR_IPV4) || - avahi_domain_ends_with(domain, AVAHI_MDNS_SUFFIX_ADDR_IPV6)) - *flags |= AVAHI_LOOKUP_USE_MULTICAST; - else - *flags |= AVAHI_LOOKUP_USE_WIDE_AREA; -} - -static AvahiSRBLookup* lookup_new( - AvahiSRecordBrowser *b, - AvahiIfIndex interface, - AvahiProtocol protocol, - AvahiLookupFlags flags, - AvahiKey *key) { - - AvahiSRBLookup *l; - - assert(b); - assert(AVAHI_IF_VALID(interface)); - assert(AVAHI_PROTO_VALID(protocol)); - - if (b->n_lookups >= AVAHI_LOOKUPS_PER_BROWSER_MAX) - /* We don't like cyclic CNAMEs */ - return NULL; - - if (!(l = avahi_new(AvahiSRBLookup, 1))) - return NULL; - - l->ref = 1; - l->record_browser = b; - l->interface = interface; - l->protocol = protocol; - l->key = avahi_key_ref(key); - l->wide_area = NULL; - l->multicast = NULL; - l->cname_lookups = NULL; - l->flags = flags; - - transport_flags_from_domain(b->server, &l->flags, key->name); - - AVAHI_LLIST_PREPEND(AvahiSRBLookup, lookups, b->lookups, l); - - b->n_lookups ++; - - return l; -} - -static void lookup_unref(AvahiSRBLookup *l) { - assert(l); - assert(l->ref >= 1); - - if (--l->ref >= 1) - return; - - AVAHI_LLIST_REMOVE(AvahiSRBLookup, lookups, l->record_browser->lookups, l); - l->record_browser->n_lookups --; - - if (l->wide_area) { - avahi_wide_area_lookup_free(l->wide_area); - l->wide_area = NULL; - } - - if (l->multicast) { - avahi_multicast_lookup_free(l->multicast); - l->multicast = NULL; - } - - while (l->cname_lookups) { - lookup_unref(l->cname_lookups->data); - l->cname_lookups = avahi_rlist_remove_by_link(l->cname_lookups, l->cname_lookups); - } - - avahi_key_unref(l->key); - avahi_free(l); -} - -static AvahiSRBLookup* lookup_ref(AvahiSRBLookup *l) { - assert(l); - assert(l->ref >= 1); - - l->ref++; - return l; -} - -static AvahiSRBLookup *lookup_find( - AvahiSRecordBrowser *b, - AvahiIfIndex interface, - AvahiProtocol protocol, - AvahiLookupFlags flags, - AvahiKey *key) { - - AvahiSRBLookup *l; - - assert(b); - - for (l = b->lookups; l; l = l->lookups_next) { - - if ((l->interface == AVAHI_IF_UNSPEC || l->interface == interface) && - (l->interface == AVAHI_PROTO_UNSPEC || l->protocol == protocol) && - l->flags == flags && - avahi_key_equal(l->key, key)) - - return l; - } - - return NULL; -} - -static void browser_cancel(AvahiSRecordBrowser *b) { - assert(b); - - if (b->root_lookup) { - lookup_unref(b->root_lookup); - b->root_lookup = NULL; - } - - if (b->defer_time_event) { - avahi_time_event_free(b->defer_time_event); - b->defer_time_event = NULL; - } -} - -static void lookup_wide_area_callback( - AvahiWideAreaLookupEngine *e, - AvahiBrowserEvent event, - AvahiLookupResultFlags flags, - AvahiRecord *r, - void *userdata) { - - AvahiSRBLookup *l = userdata; - AvahiSRecordBrowser *b; - - assert(e); - assert(l); - assert(l->ref >= 1); - - b = l->record_browser; - - if (b->dead) - return; - - lookup_ref(l); - - switch (event) { - case AVAHI_BROWSER_NEW: - assert(r); - - if (r->key->clazz == AVAHI_DNS_CLASS_IN && - r->key->type == AVAHI_DNS_TYPE_CNAME) - /* It's a CNAME record, so let's follow it. We only follow it on wide area DNS! */ - lookup_handle_cname(l, AVAHI_IF_UNSPEC, AVAHI_PROTO_UNSPEC, AVAHI_LOOKUP_USE_WIDE_AREA, r); - else { - /* It's a normal record, so let's call the user callback */ - assert(avahi_key_equal(r->key, l->key)); - - b->callback(b, AVAHI_IF_UNSPEC, AVAHI_PROTO_UNSPEC, event, r, flags, b->userdata); - } - break; - - case AVAHI_BROWSER_REMOVE: - case AVAHI_BROWSER_CACHE_EXHAUSTED: - /* Not defined for wide area DNS */ - abort(); - - case AVAHI_BROWSER_ALL_FOR_NOW: - case AVAHI_BROWSER_FAILURE: - - b->callback(b, AVAHI_IF_UNSPEC, AVAHI_PROTO_UNSPEC, event, NULL, flags, b->userdata); - break; - } - - lookup_unref(l); - -} - -static void lookup_multicast_callback( - AvahiMulticastLookupEngine *e, - AvahiIfIndex interface, - AvahiProtocol protocol, - AvahiBrowserEvent event, - AvahiLookupResultFlags flags, - AvahiRecord *r, - void *userdata) { - - AvahiSRBLookup *l = userdata; - AvahiSRecordBrowser *b; - - assert(e); - assert(l); - - b = l->record_browser; - - if (b->dead) - return; - - lookup_ref(l); - - switch (event) { - case AVAHI_BROWSER_NEW: - assert(r); - - if (r->key->clazz == AVAHI_DNS_CLASS_IN && - r->key->type == AVAHI_DNS_TYPE_CNAME) - /* It's a CNAME record, so let's follow it. We allow browsing on both multicast and wide area. */ - lookup_handle_cname(l, interface, protocol, b->flags, r); - else { - /* It's a normal record, so let's call the user callback */ - - if (avahi_server_is_record_local(b->server, interface, protocol, r)) - flags |= AVAHI_LOOKUP_RESULT_LOCAL; - - b->callback(b, interface, protocol, event, r, flags, b->userdata); - } - break; - - case AVAHI_BROWSER_REMOVE: - assert(r); - - if (r->key->clazz == AVAHI_DNS_CLASS_IN && - r->key->type == AVAHI_DNS_TYPE_CNAME) - /* It's a CNAME record, so let's drop that query! */ - lookup_drop_cname(l, interface, protocol, 0, r); - else { - /* It's a normal record, so let's call the user callback */ - assert(avahi_key_equal(b->key, l->key)); - - b->callback(b, interface, protocol, event, r, flags, b->userdata); - } - break; - - case AVAHI_BROWSER_ALL_FOR_NOW: - - b->callback(b, AVAHI_IF_UNSPEC, AVAHI_PROTO_UNSPEC, event, NULL, flags, b->userdata); - break; - - case AVAHI_BROWSER_CACHE_EXHAUSTED: - case AVAHI_BROWSER_FAILURE: - /* Not defined for multicast DNS */ - abort(); - - } - - lookup_unref(l); -} - -static int lookup_start(AvahiSRBLookup *l) { - assert(l); - - assert(!(l->flags & AVAHI_LOOKUP_USE_WIDE_AREA) != !(l->flags & AVAHI_LOOKUP_USE_MULTICAST)); - assert(!l->wide_area && !l->multicast); - - if (l->flags & AVAHI_LOOKUP_USE_WIDE_AREA) { - - if (!(l->wide_area = avahi_wide_area_lookup_new(l->record_browser->server->wide_area_lookup_engine, l->key, lookup_wide_area_callback, l))) - return -1; - - } else { - assert(l->flags & AVAHI_LOOKUP_USE_MULTICAST); - - if (!(l->multicast = avahi_multicast_lookup_new(l->record_browser->server->multicast_lookup_engine, l->interface, l->protocol, l->key, lookup_multicast_callback, l))) - return -1; - } - - return 0; -} - -static int lookup_scan_cache(AvahiSRBLookup *l) { - int n = 0; - - assert(l); - - assert(!(l->flags & AVAHI_LOOKUP_USE_WIDE_AREA) != !(l->flags & AVAHI_LOOKUP_USE_MULTICAST)); - - - if (l->flags & AVAHI_LOOKUP_USE_WIDE_AREA) { - n = (int) avahi_wide_area_scan_cache(l->record_browser->server->wide_area_lookup_engine, l->key, lookup_wide_area_callback, l); - - } else { - assert(l->flags & AVAHI_LOOKUP_USE_MULTICAST); - n = (int) avahi_multicast_lookup_engine_scan_cache(l->record_browser->server->multicast_lookup_engine, l->interface, l->protocol, l->key, lookup_multicast_callback, l); - } - - return n; -} - -static AvahiSRBLookup* lookup_add(AvahiSRecordBrowser *b, AvahiIfIndex interface, AvahiProtocol protocol, AvahiLookupFlags flags, AvahiKey *key) { - AvahiSRBLookup *l; - - assert(b); - assert(!b->dead); - - if ((l = lookup_find(b, interface, protocol, flags, key))) - return lookup_ref(l); - - if (!(l = lookup_new(b, interface, protocol, flags, key))) - return NULL; - - return l; -} - -static int lookup_go(AvahiSRBLookup *l) { - int n = 0; - assert(l); - - if (l->record_browser->dead) - return 0; - - lookup_ref(l); - - /* Browse the cache for the root request */ - n = lookup_scan_cache(l); - - /* Start the lookup */ - if (!l->record_browser->dead && l->ref > 1) { - - if ((l->flags & AVAHI_LOOKUP_USE_MULTICAST) || n == 0) - /* We do no start a query if the cache contained entries and we're on wide area */ - - if (lookup_start(l) < 0) - n = -1; - } - - lookup_unref(l); - - return n; -} - -static void lookup_handle_cname(AvahiSRBLookup *l, AvahiIfIndex interface, AvahiProtocol protocol, AvahiLookupFlags flags, AvahiRecord *r) { - AvahiKey *k; - AvahiSRBLookup *n; - - assert(l); - assert(r); - - assert(r->key->clazz == AVAHI_DNS_CLASS_IN); - assert(r->key->type == AVAHI_DNS_TYPE_CNAME); - - k = avahi_key_new(r->data.ptr.name, l->record_browser->key->clazz, l->record_browser->key->type); - n = lookup_add(l->record_browser, interface, protocol, flags, k); - avahi_key_unref(k); - - if (!n) { - avahi_log_debug(__FILE__": Failed to create SRBLookup."); - return; - } - - l->cname_lookups = avahi_rlist_prepend(l->cname_lookups, lookup_ref(n)); - - lookup_go(n); - lookup_unref(n); -} - -static void lookup_drop_cname(AvahiSRBLookup *l, AvahiIfIndex interface, AvahiProtocol protocol, AvahiLookupFlags flags, AvahiRecord *r) { - AvahiKey *k; - AvahiSRBLookup *n = NULL; - AvahiRList *rl; - - assert(r->key->clazz == AVAHI_DNS_CLASS_IN); - assert(r->key->type == AVAHI_DNS_TYPE_CNAME); - - k = avahi_key_new(r->data.ptr.name, l->record_browser->key->clazz, l->record_browser->key->type); - - for (rl = l->cname_lookups; rl; rl = rl->rlist_next) { - n = rl->data; - - assert(n); - - if ((n->interface == AVAHI_IF_UNSPEC || n->interface == interface) && - (n->interface == AVAHI_PROTO_UNSPEC || n->protocol == protocol) && - n->flags == flags && - avahi_key_equal(n->key, k)) - break; - } - - avahi_key_unref(k); - - if (rl) { - l->cname_lookups = avahi_rlist_remove_by_link(l->cname_lookups, rl); - lookup_unref(n); - } -} - -static void defer_callback(AVAHI_GCC_UNUSED AvahiTimeEvent *e, void *userdata) { - AvahiSRecordBrowser *b = userdata; - int n; - - assert(b); - assert(!b->dead); - - /* Remove the defer timeout */ - if (b->defer_time_event) { - avahi_time_event_free(b->defer_time_event); - b->defer_time_event = NULL; - } - - /* Create initial query */ - assert(!b->root_lookup); - b->root_lookup = lookup_add(b, b->interface, b->protocol, b->flags, b->key); - assert(b->root_lookup); - - n = lookup_go(b->root_lookup); - - if (b->dead) - return; - - if (n < 0) { - /* sending of the initial query failed */ - - avahi_server_set_errno(b->server, AVAHI_ERR_FAILURE); - - b->callback( - b, b->interface, b->protocol, AVAHI_BROWSER_FAILURE, NULL, - b->flags & AVAHI_LOOKUP_USE_WIDE_AREA ? AVAHI_LOOKUP_RESULT_WIDE_AREA : AVAHI_LOOKUP_RESULT_MULTICAST, - b->userdata); - - browser_cancel(b); - return; - } - - /* Tell the client that we're done with the cache */ - b->callback( - b, b->interface, b->protocol, AVAHI_BROWSER_CACHE_EXHAUSTED, NULL, - b->flags & AVAHI_LOOKUP_USE_WIDE_AREA ? AVAHI_LOOKUP_RESULT_WIDE_AREA : AVAHI_LOOKUP_RESULT_MULTICAST, - b->userdata); - - if (!b->dead && b->root_lookup && b->root_lookup->flags & AVAHI_LOOKUP_USE_WIDE_AREA && n > 0) { - - /* If we do wide area lookups and the the cache contained - * entries, we assume that it is complete, and tell the user - * so by firing ALL_FOR_NOW. */ - - b->callback(b, b->interface, b->protocol, AVAHI_BROWSER_ALL_FOR_NOW, NULL, AVAHI_LOOKUP_RESULT_WIDE_AREA, b->userdata); - } -} - -void avahi_s_record_browser_restart(AvahiSRecordBrowser *b) { - assert(b); - assert(!b->dead); - - browser_cancel(b); - - /* Request a new iteration of the cache scanning */ - if (!b->defer_time_event) { - b->defer_time_event = avahi_time_event_new(b->server->time_event_queue, NULL, defer_callback, b); - assert(b->defer_time_event); - } -} - -AvahiSRecordBrowser *avahi_s_record_browser_new( - AvahiServer *server, - AvahiIfIndex interface, - AvahiProtocol protocol, - AvahiKey *key, - AvahiLookupFlags flags, - AvahiSRecordBrowserCallback callback, - void* userdata) { - - AvahiSRecordBrowser *b; - - assert(server); - assert(key); - 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, !avahi_key_is_pattern(key), AVAHI_ERR_IS_PATTERN); - AVAHI_CHECK_VALIDITY_RETURN_NULL(server, avahi_key_is_valid(key), AVAHI_ERR_INVALID_KEY); - AVAHI_CHECK_VALIDITY_RETURN_NULL(server, AVAHI_FLAGS_VALID(flags, AVAHI_LOOKUP_USE_WIDE_AREA|AVAHI_LOOKUP_USE_MULTICAST), AVAHI_ERR_INVALID_FLAGS); - AVAHI_CHECK_VALIDITY_RETURN_NULL(server, !(flags & AVAHI_LOOKUP_USE_WIDE_AREA) || !(flags & AVAHI_LOOKUP_USE_MULTICAST), AVAHI_ERR_INVALID_FLAGS); - - if (!(b = avahi_new(AvahiSRecordBrowser, 1))) { - avahi_server_set_errno(server, AVAHI_ERR_NO_MEMORY); - return NULL; - } - - b->dead = 0; - b->server = server; - b->interface = interface; - b->protocol = protocol; - b->key = avahi_key_ref(key); - b->flags = flags; - b->callback = callback; - b->userdata = userdata; - b->n_lookups = 0; - AVAHI_LLIST_HEAD_INIT(AvahiSRBLookup, b->lookups); - b->root_lookup = NULL; - - AVAHI_LLIST_PREPEND(AvahiSRecordBrowser, browser, server->record_browsers, b); - - /* The currently cached entries are scanned a bit later, and than we will start querying, too */ - b->defer_time_event = avahi_time_event_new(server->time_event_queue, NULL, defer_callback, b); - assert(b->defer_time_event); - - return b; -} - -void avahi_s_record_browser_free(AvahiSRecordBrowser *b) { - assert(b); - assert(!b->dead); - - b->dead = 1; - b->server->need_browser_cleanup = 1; - - browser_cancel(b); -} - -void avahi_s_record_browser_destroy(AvahiSRecordBrowser *b) { - assert(b); - - browser_cancel(b); - - AVAHI_LLIST_REMOVE(AvahiSRecordBrowser, browser, b->server->record_browsers, b); - - avahi_key_unref(b->key); - - avahi_free(b); -} - -void avahi_browser_cleanup(AvahiServer *server) { - AvahiSRecordBrowser *b; - AvahiSRecordBrowser *n; - - assert(server); - - while (server->need_browser_cleanup) { - server->need_browser_cleanup = 0; - - for (b = server->record_browsers; b; b = n) { - n = b->browser_next; - - if (b->dead) - avahi_s_record_browser_destroy(b); - } - } - - if (server->wide_area_lookup_engine) - avahi_wide_area_cleanup(server->wide_area_lookup_engine); - avahi_multicast_lookup_engine_cleanup(server->multicast_lookup_engine); -} - |