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-rw-r--r--avahi-core/psched.c738
1 files changed, 0 insertions, 738 deletions
diff --git a/avahi-core/psched.c b/avahi-core/psched.c
deleted file mode 100644
index 5121054..0000000
--- a/avahi-core/psched.c
+++ /dev/null
@@ -1,738 +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 <string.h>
-
-#include "util.h"
-#include "psched.h"
-
-#define AVAHI_QUERY_HISTORY_MSEC 100
-#define AVAHI_QUERY_DEFER_MSEC 100
-#define AVAHI_RESPONSE_HISTORY_MSEC 700
-#define AVAHI_RESPONSE_DEFER_MSEC 20
-#define AVAHI_RESPONSE_JITTER_MSEC 100
-#define AVAHI_PROBE_DEFER_MSEC 70
-
-AvahiPacketScheduler *avahi_packet_scheduler_new(AvahiServer *server, AvahiInterface *i) {
- AvahiPacketScheduler *s;
-
- g_assert(server);
- g_assert(i);
-
- s = g_new(AvahiPacketScheduler, 1);
- s->server = server;
- s->interface = i;
-
- AVAHI_LLIST_HEAD_INIT(AvahiQueryJob, s->query_jobs);
- AVAHI_LLIST_HEAD_INIT(AvahiResponseJob, s->response_jobs);
- AVAHI_LLIST_HEAD_INIT(AvahiKnownAnswer, s->known_answers);
- AVAHI_LLIST_HEAD_INIT(AvahiProbeJob, s->probe_jobs);
-
- return s;
-}
-
-static void query_job_free(AvahiPacketScheduler *s, AvahiQueryJob *qj) {
- g_assert(qj);
-
- if (qj->time_event)
- avahi_time_event_queue_remove(qj->scheduler->server->time_event_queue, qj->time_event);
-
- AVAHI_LLIST_REMOVE(AvahiQueryJob, jobs, s->query_jobs, qj);
-
- avahi_key_unref(qj->key);
- g_free(qj);
-}
-
-static void response_job_free(AvahiPacketScheduler *s, AvahiResponseJob *rj) {
- g_assert(rj);
-
- if (rj->time_event)
- avahi_time_event_queue_remove(rj->scheduler->server->time_event_queue, rj->time_event);
-
- AVAHI_LLIST_REMOVE(AvahiResponseJob, jobs, s->response_jobs, rj);
-
- avahi_record_unref(rj->record);
- g_free(rj);
-}
-
-static void probe_job_free(AvahiPacketScheduler *s, AvahiProbeJob *pj) {
- g_assert(pj);
-
- if (pj->time_event)
- avahi_time_event_queue_remove(pj->scheduler->server->time_event_queue, pj->time_event);
-
- AVAHI_LLIST_REMOVE(AvahiProbeJob, jobs, s->probe_jobs, pj);
-
- avahi_record_unref(pj->record);
- g_free(pj);
-}
-
-void avahi_packet_scheduler_free(AvahiPacketScheduler *s) {
- AvahiQueryJob *qj;
- AvahiResponseJob *rj;
- AvahiProbeJob *pj;
-
- g_assert(s);
-
- g_assert(!s->known_answers);
-
- while ((qj = s->query_jobs))
- query_job_free(s, qj);
- while ((rj = s->response_jobs))
- response_job_free(s, rj);
- while ((pj = s->probe_jobs))
- probe_job_free(s, pj);
-
- g_free(s);
-}
-
-static gpointer known_answer_walk_callback(AvahiCache *c, AvahiKey *pattern, AvahiCacheEntry *e, gpointer userdata) {
- AvahiPacketScheduler *s = userdata;
- AvahiKnownAnswer *ka;
-
- g_assert(c);
- g_assert(pattern);
- g_assert(e);
- g_assert(s);
-
- if (avahi_cache_entry_half_ttl(c, e))
- return NULL;
-
- ka = g_new0(AvahiKnownAnswer, 1);
- ka->scheduler = s;
- ka->record = avahi_record_ref(e->record);
-
- AVAHI_LLIST_PREPEND(AvahiKnownAnswer, known_answer, s->known_answers, ka);
- return NULL;
-}
-
-static guint8* packet_add_query_job(AvahiPacketScheduler *s, AvahiDnsPacket *p, AvahiQueryJob *qj) {
- guint8 *d;
-
- g_assert(s);
- g_assert(p);
- g_assert(qj);
-
- if ((d = avahi_dns_packet_append_key(p, qj->key, FALSE))) {
- GTimeVal tv;
-
- qj->done = 1;
-
- /* Drop query after some time from history */
- avahi_elapse_time(&tv, AVAHI_QUERY_HISTORY_MSEC, 0);
- avahi_time_event_queue_update(s->server->time_event_queue, qj->time_event, &tv);
-
- g_get_current_time(&qj->delivery);
-
- /* Add all matching known answers to the list */
- avahi_cache_walk(s->interface->cache, qj->key, known_answer_walk_callback, s);
- }
-
- return d;
-}
-
-static void append_known_answers_and_send(AvahiPacketScheduler *s, AvahiDnsPacket *p) {
- AvahiKnownAnswer *ka;
- guint n;
- g_assert(s);
- g_assert(p);
-
- n = 0;
-
- while ((ka = s->known_answers)) {
-
- while (!avahi_dns_packet_append_record(p, ka->record, FALSE, 0)) {
-
- g_assert(!avahi_dns_packet_is_empty(p));
-
- avahi_dns_packet_set_field(p, AVAHI_DNS_FIELD_FLAGS, avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_FLAGS) | AVAHI_DNS_FLAG_TC);
- avahi_dns_packet_set_field(p, AVAHI_DNS_FIELD_ANCOUNT, n);
- avahi_interface_send_packet(s->interface, p);
- avahi_dns_packet_free(p);
-
- p = avahi_dns_packet_new_query(s->interface->hardware->mtu);
- n = 0;
- }
-
- AVAHI_LLIST_REMOVE(AvahiKnownAnswer, known_answer, s->known_answers, ka);
- avahi_record_unref(ka->record);
- g_free(ka);
-
- n++;
- }
-
- avahi_dns_packet_set_field(p, AVAHI_DNS_FIELD_ANCOUNT, n);
- avahi_interface_send_packet(s->interface, p);
- avahi_dns_packet_free(p);
-}
-
-static void query_elapse(AvahiTimeEvent *e, gpointer data) {
- AvahiQueryJob *qj = data;
- AvahiPacketScheduler *s;
- AvahiDnsPacket *p;
- guint n;
- guint8 *d;
-
- g_assert(qj);
- s = qj->scheduler;
-
- if (qj->done) {
- /* Lets remove it from the history */
- query_job_free(s, qj);
- return;
- }
-
- g_assert(!s->known_answers);
-
- p = avahi_dns_packet_new_query(s->interface->hardware->mtu);
- d = packet_add_query_job(s, p, qj);
- g_assert(d);
- n = 1;
-
- /* Try to fill up packet with more queries, if available */
- for (qj = s->query_jobs; qj; qj = qj->jobs_next) {
-
- if (qj->done)
- continue;
-
- if (!packet_add_query_job(s, p, qj))
- break;
-
- n++;
- }
-
- avahi_dns_packet_set_field(p, AVAHI_DNS_FIELD_QDCOUNT, n);
-
- /* Now add known answers */
- append_known_answers_and_send(s, p);
-}
-
-static AvahiQueryJob* query_job_new(AvahiPacketScheduler *s, AvahiKey *key) {
- AvahiQueryJob *qj;
-
- g_assert(s);
- g_assert(key);
-
- qj = g_new(AvahiQueryJob, 1);
- qj->scheduler = s;
- qj->key = avahi_key_ref(key);
- qj->done = FALSE;
- qj->time_event = NULL;
-
- AVAHI_LLIST_PREPEND(AvahiQueryJob, jobs, s->query_jobs, qj);
-
- return qj;
-}
-
-static AvahiQueryJob* look_for_query(AvahiPacketScheduler *s, AvahiKey *key) {
- AvahiQueryJob *qj;
-
- g_assert(s);
- g_assert(key);
-
- for (qj = s->query_jobs; qj; qj = qj->jobs_next)
- if (avahi_key_equal(qj->key, key))
- return qj;
-
- return NULL;
-}
-
-gboolean avahi_packet_scheduler_post_query(AvahiPacketScheduler *s, AvahiKey *key, gboolean immediately) {
- GTimeVal tv;
- AvahiQueryJob *qj;
-
- g_assert(s);
- g_assert(key);
-
- avahi_elapse_time(&tv, immediately ? 0 : AVAHI_QUERY_DEFER_MSEC, 0);
-
- if ((qj = look_for_query(s, key))) {
- glong d = avahi_timeval_diff(&tv, &qj->delivery);
-
- /* Duplicate questions suppression */
- if (!qj->done || d <= AVAHI_QUERY_HISTORY_MSEC*1000) {
- g_message("WARNING! DUPLICATE QUERY SUPPRESSION ACTIVE!");
-
- if (!qj->done && d < 0) {
- /* If the new entry should be scheduled earlier,
- * update the old entry */
- qj->delivery = tv;
- avahi_time_event_queue_update(s->server->time_event_queue, qj->time_event, &qj->delivery);
- }
-
- return FALSE;
- } else
- query_job_free(s, qj);
- }
-
- qj = query_job_new(s, key);
- qj->delivery = tv;
- qj->time_event = avahi_time_event_queue_add(s->server->time_event_queue, &qj->delivery, query_elapse, qj);
- return TRUE;
-}
-
-
-void avahi_packet_scheduler_incoming_query(AvahiPacketScheduler *s, AvahiKey *key) {
- AvahiQueryJob *qj;
- GTimeVal tv;
-
- g_assert(s);
- g_assert(key);
-
- /* This function is called whenever an incoming query was
- * receieved. We mark all matching queries that match as done. The
- * keyword is "DUPLICATE QUESTION SUPPRESION". */
-
- if (!(qj = look_for_query(s, key)))
- qj = query_job_new(s, key);
-
- qj->done = TRUE;
-
- /* Drop the query after some time */
- avahi_elapse_time(&tv, AVAHI_QUERY_HISTORY_MSEC, 0);
-
- if (qj->time_event)
- avahi_time_event_queue_update(s->server->time_event_queue, qj->time_event, &tv);
- else
- qj->time_event = avahi_time_event_queue_add(s->server->time_event_queue, &tv, query_elapse, qj);
-
- g_get_current_time(&qj->delivery);
-}
-
-static guint8* packet_add_response_job(AvahiPacketScheduler *s, AvahiDnsPacket *p, AvahiResponseJob *rj) {
- guint8 *d;
-
- g_assert(s);
- g_assert(p);
- g_assert(rj);
-
- if ((d = avahi_dns_packet_append_record(p, rj->record, rj->flush_cache, 0))) {
- GTimeVal tv;
-
- rj->done = 1;
-
- /* Drop response after some time from history */
- avahi_elapse_time(&tv, AVAHI_RESPONSE_HISTORY_MSEC, 0);
- avahi_time_event_queue_update(s->server->time_event_queue, rj->time_event, &tv);
-
- g_get_current_time(&rj->delivery);
- }
-
- return d;
-}
-
-static void send_response_packet(AvahiPacketScheduler *s, AvahiResponseJob *rj) {
- AvahiDnsPacket *p;
- guint n;
-
- g_assert(s);
-
- p = avahi_dns_packet_new_response(s->interface->hardware->mtu, TRUE);
- n = 0;
-
- /* If a job was specified, put it in the packet. */
- if (rj) {
- guint8 *d;
- d = packet_add_response_job(s, p, rj);
- g_assert(d);
- n++;
- }
-
- /* Try to fill up packet with more responses, if available */
- for (rj = s->response_jobs; rj; rj = rj->jobs_next) {
-
- if (rj->done)
- continue;
-
- if (!packet_add_response_job(s, p, rj))
- break;
-
- n++;
- }
-
- avahi_dns_packet_set_field(p, AVAHI_DNS_FIELD_ANCOUNT, n);
- avahi_interface_send_packet(s->interface, p);
- avahi_dns_packet_free(p);
-}
-
-static void response_elapse(AvahiTimeEvent *e, gpointer data) {
- AvahiResponseJob *rj = data;
- AvahiPacketScheduler *s;
-
- g_assert(rj);
- s = rj->scheduler;
-
- if (rj->done) {
- /* Lets remove it from the history */
- response_job_free(s, rj);
- return;
- }
-
- send_response_packet(s, rj);
-}
-
-static AvahiResponseJob* look_for_response(AvahiPacketScheduler *s, AvahiRecord *record) {
- AvahiResponseJob *rj;
-
- g_assert(s);
- g_assert(record);
-
- for (rj = s->response_jobs; rj; rj = rj->jobs_next)
- if (avahi_record_equal_no_ttl(rj->record, record))
- return rj;
-
- return NULL;
-}
-
-static AvahiResponseJob* response_job_new(AvahiPacketScheduler *s, AvahiRecord *record) {
- AvahiResponseJob *rj;
-
- g_assert(s);
- g_assert(record);
-
- rj = g_new(AvahiResponseJob, 1);
- rj->scheduler = s;
- rj->record = avahi_record_ref(record);
- rj->done = FALSE;
- rj->time_event = NULL;
- rj->flush_cache = FALSE;
- rj->querier_valid = FALSE;
-
- AVAHI_LLIST_PREPEND(AvahiResponseJob, jobs, s->response_jobs, rj);
-
- return rj;
-}
-
-gboolean avahi_packet_scheduler_post_response(AvahiPacketScheduler *s, AvahiRecord *record, gboolean flush_cache, gboolean immediately, const AvahiAddress *querier) {
- AvahiResponseJob *rj;
- GTimeVal tv;
-
- g_assert(s);
- g_assert(record);
-
- g_assert(!avahi_key_is_pattern(record->key));
-
- avahi_elapse_time(&tv, immediately ? 0 : AVAHI_RESPONSE_DEFER_MSEC, immediately ? 0 : AVAHI_RESPONSE_JITTER_MSEC);
-
- /* Don't send out duplicates */
-
- if ((rj = look_for_response(s, record))) {
-
- glong d = avahi_timeval_diff(&tv, &rj->delivery);
-
- /* If there's already a matching packet in our history or in
- * the schedule, we do nothing. */
-
- if ((!!record->ttl == !!rj->record->ttl) &&
- (rj->flush_cache || !flush_cache) &&
- ((!rj->done && d >= 0) || (rj->done && d <= AVAHI_RESPONSE_HISTORY_MSEC*1000))) {
-
- g_message("Duplicate suppresion active.");
- return FALSE;
- }
-
- /* If the old job was not yet done but scheduled earlier than
- * our new one, we chedule our new job at the same time. */
- if (!rj->done && d > 0)
- tv = rj->delivery;
-
- /* If the old job had the flush_cache bit enabled, we must
- enable it on our new one, too */
- if (!rj->done && rj->flush_cache)
- flush_cache = TRUE;
-
- /* For known answer suppresion we have record for which host this data was intended */
- if (querier && !rj->done && (!rj->querier_valid || avahi_address_cmp(&rj->querier, querier) != 0))
- querier = NULL;
-
- /* The old job wasn't good enough, so let's drop it */
- response_job_free(s, rj);
- }
-
- /* Create a new job and schedule it */
- rj = response_job_new(s, record);
- rj->flush_cache = flush_cache;
- rj->delivery = tv;
- rj->time_event = avahi_time_event_queue_add(s->server->time_event_queue, &rj->delivery, response_elapse, rj);
-
- if ((rj->querier_valid = !!querier))
- rj->querier = *querier;
-
- return TRUE;
-}
-
-void response_job_set_elapse_time(AvahiPacketScheduler *s, AvahiResponseJob *rj, guint msec, guint jitter) {
- GTimeVal tv;
-
- g_assert(s);
- g_assert(rj);
-
- avahi_elapse_time(&tv, msec, jitter);
-
- if (rj->time_event)
- avahi_time_event_queue_update(s->server->time_event_queue, rj->time_event, &tv);
- else
- rj->time_event = avahi_time_event_queue_add(s->server->time_event_queue, &tv, response_elapse, rj);
-}
-
-void avahi_packet_scheduler_incoming_response(AvahiPacketScheduler *s, AvahiRecord *record, gboolean flush_cache) {
- AvahiResponseJob *rj = NULL;
-
- g_assert(s);
- g_assert(record);
-
- /* This function is called whenever an incoming response was
- * receieved. We drop all scheduled responses which match
- * here. The keyword is "DUPLICATE ANSWER SUPPRESION". */
-
- if ((rj = look_for_response(s, record))) {
-
- if (!rj->done) {
-
- if (rj->flush_cache && !flush_cache)
- /* The incoming response didn't have flush_cache
- * set, but our scheduled has => we still have to
- * send our response */
- return;
-
-
- if (!!record->ttl != !!rj->record->ttl) {
- /* Either one was a goodbye packet but other was
- * none => we still have to send our response */
- return;
- }
- }
-
- /* The two responses match, so let's mark the history
- * entry as done or update it */
- }
-
- /* No matching job was found. Add the query to the history */
- if (!rj)
- rj = response_job_new(s, record);
- else {
- avahi_record_unref(rj->record);
- rj->record = avahi_record_ref(record);
- }
-
- rj->done = TRUE;
- rj->flush_cache = rj->flush_cache || flush_cache;
-
- /* Drop response after 500ms from history */
- response_job_set_elapse_time(s, rj, AVAHI_RESPONSE_HISTORY_MSEC, 0);
-
- g_get_current_time(&rj->delivery);
-}
-
-
-void avahi_packet_scheduler_incoming_known_answer(AvahiPacketScheduler *s, AvahiRecord *record, const AvahiAddress *querier) {
- AvahiResponseJob *rj;
-
- g_assert(s);
- g_assert(record);
- g_assert(querier);
-
- /* Check whether a matching job has been scheduled */
- if (!(rj = look_for_response(s, record)) || rj->done)
- return;
-
- /* Chech whether another querier demanded the original job */
- if (!rj->querier_valid || avahi_address_cmp(&rj->querier, querier) != 0)
- return;
-
- /* Check whether one of them is a goodbye packet, while the other is not */
- if (!!record->ttl != !!rj->record->ttl)
- return;
-
- /* Check whether the known answer has a good TTL */
- if (record->ttl <= rj->record->ttl/2)
- return;
-
- g_message("Known answer suppression active!");
- response_job_free(s, rj);
-}
-
-void avahi_packet_scheduler_flush_responses(AvahiPacketScheduler *s) {
- AvahiResponseJob *rj;
-
- g_assert(s);
-
- /* Send all scheduled responses, ignoring the scheduled time */
-
- for (rj = s->response_jobs; rj; rj = rj->jobs_next)
- if (!rj->done)
- send_response_packet(s, rj);
-}
-
-static AvahiProbeJob* probe_job_new(AvahiPacketScheduler *s, AvahiRecord *record) {
- AvahiProbeJob *pj;
-
- g_assert(s);
- g_assert(record);
-
- pj = g_new(AvahiProbeJob, 1);
- pj->scheduler = s;
- pj->record = avahi_record_ref(record);
- pj->time_event = NULL;
- pj->chosen = FALSE;
-
- AVAHI_LLIST_PREPEND(AvahiProbeJob, jobs, s->probe_jobs, pj);
-
- return pj;
-}
-
-static guint8* packet_add_probe_query(AvahiPacketScheduler *s, AvahiDnsPacket *p, AvahiProbeJob *pj) {
- guint size;
- guint8 *ret;
- AvahiKey *k;
-
- g_assert(s);
- g_assert(p);
- g_assert(pj);
-
- g_assert(!pj->chosen);
-
- /* Estimate the size for this record */
- size =
- avahi_key_get_estimate_size(pj->record->key) +
- avahi_record_get_estimate_size(pj->record);
-
- /* Too large */
- if (size > avahi_dns_packet_space(p))
- return NULL;
-
- /* Create the probe query */
- k = avahi_key_new(pj->record->key->name, pj->record->key->class, AVAHI_DNS_TYPE_ANY);
- ret = avahi_dns_packet_append_key(p, k, FALSE);
- g_assert(ret);
-
- /* Mark this job for addition to the packet */
- pj->chosen = TRUE;
-
- /* Scan for more jobs whith matching key pattern */
- for (pj = s->probe_jobs; pj; pj = pj->jobs_next) {
- if (pj->chosen)
- continue;
-
- /* Does the record match the probe? */
- if (k->class != pj->record->key->class || !avahi_domain_equal(k->name, pj->record->key->name))
- continue;
-
- /* This job wouldn't fit in */
- if (avahi_record_get_estimate_size(pj->record) > avahi_dns_packet_space(p))
- break;
-
- /* Mark this job for addition to the packet */
- pj->chosen = TRUE;
- }
-
- avahi_key_unref(k);
-
- return ret;
-}
-
-static void probe_elapse(AvahiTimeEvent *e, gpointer data) {
- AvahiProbeJob *pj = data, *next;
- AvahiPacketScheduler *s;
- AvahiDnsPacket *p;
- guint n;
-
- g_assert(pj);
- s = pj->scheduler;
-
- p = avahi_dns_packet_new_query(s->interface->hardware->mtu);
-
- /* Add the import probe */
- if (!packet_add_probe_query(s, p, pj)) {
- g_warning("Record too large! ---");
- avahi_dns_packet_free(p);
- return;
- }
-
- n = 1;
-
- /* Try to fill up packet with more probes, if available */
- for (pj = s->probe_jobs; pj; pj = pj->jobs_next) {
-
- if (pj->chosen)
- continue;
-
- if (!packet_add_probe_query(s, p, pj))
- break;
-
- n++;
- }
-
- avahi_dns_packet_set_field(p, AVAHI_DNS_FIELD_QDCOUNT, n);
-
- n = 0;
-
- /* Now add the chosen records to the authorative section */
- for (pj = s->probe_jobs; pj; pj = next) {
-
- next = pj->jobs_next;
-
- if (!pj->chosen)
- continue;
-
- if (!avahi_dns_packet_append_record(p, pj->record, FALSE, 0)) {
- g_warning("Bad probe size estimate!");
-
- /* Unmark all following jobs */
- for (; pj; pj = pj->jobs_next)
- pj->chosen = FALSE;
-
- break;
- }
-
- probe_job_free(s, pj);
-
- n ++;
- }
-
- avahi_dns_packet_set_field(p, AVAHI_DNS_FIELD_NSCOUNT, n);
-
- /* Send it now */
- avahi_interface_send_packet(s->interface, p);
- avahi_dns_packet_free(p);
-}
-
-gboolean avahi_packet_scheduler_post_probe(AvahiPacketScheduler *s, AvahiRecord *record, gboolean immediately) {
- AvahiProbeJob *pj;
- GTimeVal tv;
-
- g_assert(s);
- g_assert(record);
- g_assert(!avahi_key_is_pattern(record->key));
-
- avahi_elapse_time(&tv, immediately ? 0 : AVAHI_PROBE_DEFER_MSEC, 0);
-
- /* Create a new job and schedule it */
- pj = probe_job_new(s, record);
- pj->delivery = tv;
- pj->time_event = avahi_time_event_queue_add(s->server->time_event_queue, &pj->delivery, probe_elapse, pj);
-
- return TRUE;
-}
generated by cgit (git 2.34.1) at 2024-05-24 04:00:56 +0000