--- /dev/null
+/***
+ 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/domain.h>
+#include <avahi/timeval.h>
+#include <avahi/malloc.h>
+
+#include "probe-sched.h"
+#include <avahi/log.h>
+#include "rr-util.h"
+
+#define AVAHI_PROBE_HISTORY_MSEC 150
+#define AVAHI_PROBE_DEFER_MSEC 50
+
+typedef struct AvahiProbeJob AvahiProbeJob;
+
+struct AvahiProbeJob {
+ AvahiProbeScheduler *scheduler;
+ AvahiTimeEvent *time_event;
+
+ int chosen; /* Use for packet assembling */
+ int done;
+ struct timeval delivery;
+
+ AvahiRecord *record;
+
+ AVAHI_LLIST_FIELDS(AvahiProbeJob, jobs);
+};
+
+struct AvahiProbeScheduler {
+ AvahiInterface *interface;
+ AvahiTimeEventQueue *time_event_queue;
+
+ AVAHI_LLIST_HEAD(AvahiProbeJob, jobs);
+ AVAHI_LLIST_HEAD(AvahiProbeJob, history);
+};
+
+static AvahiProbeJob* job_new(AvahiProbeScheduler *s, AvahiRecord *record, int done) {
+ AvahiProbeJob *pj;
+
+ assert(s);
+ assert(record);
+
+ if (!(pj = avahi_new(AvahiProbeJob, 1))) {
+ avahi_log_error(__FILE__": Out of memory");
+ return NULL; /* OOM */
+ }
+
+ pj->scheduler = s;
+ pj->record = avahi_record_ref(record);
+ pj->time_event = NULL;
+ pj->chosen = 0;
+
+ if ((pj->done = done))
+ AVAHI_LLIST_PREPEND(AvahiProbeJob, jobs, s->history, pj);
+ else
+ AVAHI_LLIST_PREPEND(AvahiProbeJob, jobs, s->jobs, pj);
+
+ return pj;
+}
+
+static void job_free(AvahiProbeScheduler *s, AvahiProbeJob *pj) {
+ assert(pj);
+
+ if (pj->time_event)
+ avahi_time_event_free(pj->time_event);
+
+ if (pj->done)
+ AVAHI_LLIST_REMOVE(AvahiProbeJob, jobs, s->history, pj);
+ else
+ AVAHI_LLIST_REMOVE(AvahiProbeJob, jobs, s->jobs, pj);
+
+ avahi_record_unref(pj->record);
+ avahi_free(pj);
+}
+
+static void elapse_callback(AvahiTimeEvent *e, void* data);
+
+static void job_set_elapse_time(AvahiProbeScheduler *s, AvahiProbeJob *pj, unsigned msec, unsigned jitter) {
+ struct timeval tv;
+
+ assert(s);
+ assert(pj);
+
+ avahi_elapse_time(&tv, msec, jitter);
+
+ if (pj->time_event)
+ avahi_time_event_update(pj->time_event, &tv);
+ else
+ pj->time_event = avahi_time_event_new(s->time_event_queue, &tv, elapse_callback, pj);
+}
+
+static void job_mark_done(AvahiProbeScheduler *s, AvahiProbeJob *pj) {
+ assert(s);
+ assert(pj);
+
+ assert(!pj->done);
+
+ AVAHI_LLIST_REMOVE(AvahiProbeJob, jobs, s->jobs, pj);
+ AVAHI_LLIST_PREPEND(AvahiProbeJob, jobs, s->history, pj);
+
+ pj->done = 1;
+
+ job_set_elapse_time(s, pj, AVAHI_PROBE_HISTORY_MSEC, 0);
+ gettimeofday(&pj->delivery, NULL);
+}
+
+AvahiProbeScheduler *avahi_probe_scheduler_new(AvahiInterface *i) {
+ AvahiProbeScheduler *s;
+
+ assert(i);
+
+ if (!(s = avahi_new(AvahiProbeScheduler, 1))) {
+ avahi_log_error(__FILE__": Out of memory");
+ return NULL;
+ }
+
+ s->interface = i;
+ s->time_event_queue = i->monitor->server->time_event_queue;
+
+ AVAHI_LLIST_HEAD_INIT(AvahiProbeJob, s->jobs);
+ AVAHI_LLIST_HEAD_INIT(AvahiProbeJob, s->history);
+
+ return s;
+}
+
+void avahi_probe_scheduler_free(AvahiProbeScheduler *s) {
+ assert(s);
+
+ avahi_probe_scheduler_clear(s);
+ avahi_free(s);
+}
+
+void avahi_probe_scheduler_clear(AvahiProbeScheduler *s) {
+ assert(s);
+
+ while (s->jobs)
+ job_free(s, s->jobs);
+ while (s->history)
+ job_free(s, s->history);
+}
+
+static int packet_add_probe_query(AvahiProbeScheduler *s, AvahiDnsPacket *p, AvahiProbeJob *pj) {
+ size_t size;
+ AvahiKey *k;
+ int b;
+
+ assert(s);
+ assert(p);
+ assert(pj);
+
+ 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 0;
+
+ /* Create the probe query */
+ if (!(k = avahi_key_new(pj->record->key->name, pj->record->key->clazz, AVAHI_DNS_TYPE_ANY)))
+ return 0; /* OOM */
+
+ b = !!avahi_dns_packet_append_key(p, k, 0);
+ assert(b);
+
+ /* Mark this job for addition to the packet */
+ pj->chosen = 1;
+
+ /* Scan for more jobs whith matching key pattern */
+ for (pj = s->jobs; pj; pj = pj->jobs_next) {
+ if (pj->chosen)
+ continue;
+
+ /* Does the record match the probe? */
+ if (k->clazz != pj->record->key->clazz || !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 = 1;
+ }
+
+ avahi_key_unref(k);
+
+ return 1;
+}
+
+static void elapse_callback(AVAHI_GCC_UNUSED AvahiTimeEvent *e, void* data) {
+ AvahiProbeJob *pj = data, *next;
+ AvahiProbeScheduler *s;
+ AvahiDnsPacket *p;
+ unsigned n;
+
+ assert(pj);
+ s = pj->scheduler;
+
+ if (pj->done) {
+ /* Lets remove it from the history */
+ job_free(s, pj);
+ return;
+ }
+
+ if (!(p = avahi_dns_packet_new_query(s->interface->hardware->mtu)))
+ return; /* OOM */
+ n = 1;
+
+ /* Add the import probe */
+ if (!packet_add_probe_query(s, p, pj)) {
+ size_t size;
+ AvahiKey *k;
+ int b;
+
+ avahi_dns_packet_free(p);
+
+ /* The probe didn't fit in the package, so let's allocate a larger one */
+
+ size =
+ avahi_key_get_estimate_size(pj->record->key) +
+ avahi_record_get_estimate_size(pj->record) +
+ AVAHI_DNS_PACKET_HEADER_SIZE;
+
+ if (!(p = avahi_dns_packet_new_query(size + AVAHI_DNS_PACKET_EXTRA_SIZE)))
+ return; /* OOM */
+
+ if (!(k = avahi_key_new(pj->record->key->name, pj->record->key->clazz, AVAHI_DNS_TYPE_ANY))) {
+ avahi_dns_packet_free(p);
+ return; /* OOM */
+ }
+
+ b = avahi_dns_packet_append_key(p, k, 0) && avahi_dns_packet_append_record(p, pj->record, 0, 0);
+ avahi_key_unref(k);
+
+ if (b) {
+ avahi_dns_packet_set_field(p, AVAHI_DNS_FIELD_NSCOUNT, 1);
+ avahi_dns_packet_set_field(p, AVAHI_DNS_FIELD_QDCOUNT, 1);
+ avahi_interface_send_packet(s->interface, p);
+ } else
+ avahi_log_warn("Probe record too large, cannot send");
+
+ avahi_dns_packet_free(p);
+ job_mark_done(s, pj);
+
+ return;
+ }
+
+ /* Try to fill up packet with more probes, if available */
+ for (pj = s->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->jobs; pj; pj = next) {
+
+ next = pj->jobs_next;
+
+ if (!pj->chosen)
+ continue;
+
+ if (!avahi_dns_packet_append_record(p, pj->record, 0, 0)) {
+/* avahi_log_warn("Bad probe size estimate!"); */
+
+ /* Unmark all following jobs */
+ for (; pj; pj = pj->jobs_next)
+ pj->chosen = 0;
+
+ break;
+ }
+
+ job_mark_done(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);
+}
+
+static AvahiProbeJob* find_scheduled_job(AvahiProbeScheduler *s, AvahiRecord *record) {
+ AvahiProbeJob *pj;
+
+ assert(s);
+ assert(record);
+
+ for (pj = s->jobs; pj; pj = pj->jobs_next) {
+ assert(!pj->done);
+
+ if (avahi_record_equal_no_ttl(pj->record, record))
+ return pj;
+ }
+
+ return NULL;
+}
+
+static AvahiProbeJob* find_history_job(AvahiProbeScheduler *s, AvahiRecord *record) {
+ AvahiProbeJob *pj;
+
+ assert(s);
+ assert(record);
+
+ for (pj = s->history; pj; pj = pj->jobs_next) {
+ assert(pj->done);
+
+ if (avahi_record_equal_no_ttl(pj->record, record)) {
+ /* Check whether this entry is outdated */
+
+ if (avahi_age(&pj->delivery) > AVAHI_PROBE_HISTORY_MSEC*1000) {
+ /* it is outdated, so let's remove it */
+ job_free(s, pj);
+ return NULL;
+ }
+
+ return pj;
+ }
+ }
+
+ return NULL;
+}
+
+int avahi_probe_scheduler_post(AvahiProbeScheduler *s, AvahiRecord *record, int immediately) {
+ AvahiProbeJob *pj;
+ struct timeval tv;
+
+ assert(s);
+ assert(record);
+ assert(!avahi_key_is_pattern(record->key));
+
+ if ((pj = find_history_job(s, record)))
+ return 0;
+
+ avahi_elapse_time(&tv, immediately ? 0 : AVAHI_PROBE_DEFER_MSEC, 0);
+
+ if ((pj = find_scheduled_job(s, record))) {
+
+ if (avahi_timeval_compare(&tv, &pj->delivery) < 0) {
+ /* If the new entry should be scheduled earlier, update the old entry */
+ pj->delivery = tv;
+ avahi_time_event_update(pj->time_event, &pj->delivery);
+ }
+
+ return 1;
+ } else {
+ /* Create a new job and schedule it */
+ if (!(pj = job_new(s, record, 0)))
+ return 0; /* OOM */
+
+ pj->delivery = tv;
+ pj->time_event = avahi_time_event_new(s->time_event_queue, &pj->delivery, elapse_callback, pj);
+
+
+/* avahi_log_debug("Accepted new probe job."); */
+
+ return 1;
+ }
+}
projects / catta / blobdiff