]> git.meshlink.io Git - catta/blobdiff - src/probe-sched.c
Merge branch 'release/0.0.1'
[catta] / src / probe-sched.c
diff --git a/src/probe-sched.c b/src/probe-sched.c
new file mode 100644 (file)
index 0000000..7d417ad
--- /dev/null
@@ -0,0 +1,397 @@
+/***
+  This file is part of catta.
+
+  catta 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.
+
+  catta 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 catta; 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 <catta/domain.h>
+#include <catta/timeval.h>
+#include <catta/malloc.h>
+
+#include "probe-sched.h"
+#include <catta/log.h>
+#include "rr-util.h"
+
+#define CATTA_PROBE_HISTORY_MSEC 150
+#define CATTA_PROBE_DEFER_MSEC 50
+
+typedef struct CattaProbeJob CattaProbeJob;
+
+struct CattaProbeJob {
+    CattaProbeScheduler *scheduler;
+    CattaTimeEvent *time_event;
+
+    int chosen; /* Use for packet assembling */
+    int done;
+    struct timeval delivery;
+
+    CattaRecord *record;
+
+    CATTA_LLIST_FIELDS(CattaProbeJob, jobs);
+};
+
+struct CattaProbeScheduler {
+    CattaInterface *iface;
+    CattaTimeEventQueue *time_event_queue;
+
+    CATTA_LLIST_HEAD(CattaProbeJob, jobs);
+    CATTA_LLIST_HEAD(CattaProbeJob, history);
+};
+
+static CattaProbeJob* job_new(CattaProbeScheduler *s, CattaRecord *record, int done) {
+    CattaProbeJob *pj;
+
+    assert(s);
+    assert(record);
+
+    if (!(pj = catta_new(CattaProbeJob, 1))) {
+        catta_log_error(__FILE__": Out of memory");
+        return NULL; /* OOM */
+    }
+
+    pj->scheduler = s;
+    pj->record = catta_record_ref(record);
+    pj->time_event = NULL;
+    pj->chosen = 0;
+
+    if ((pj->done = done))
+        CATTA_LLIST_PREPEND(CattaProbeJob, jobs, s->history, pj);
+    else
+        CATTA_LLIST_PREPEND(CattaProbeJob, jobs, s->jobs, pj);
+
+    return pj;
+}
+
+static void job_free(CattaProbeScheduler *s, CattaProbeJob *pj) {
+    assert(pj);
+
+    if (pj->time_event)
+        catta_time_event_free(pj->time_event);
+
+    if (pj->done)
+        CATTA_LLIST_REMOVE(CattaProbeJob, jobs, s->history, pj);
+    else
+        CATTA_LLIST_REMOVE(CattaProbeJob, jobs, s->jobs, pj);
+
+    catta_record_unref(pj->record);
+    catta_free(pj);
+}
+
+static void elapse_callback(CattaTimeEvent *e, void* data);
+
+static void job_set_elapse_time(CattaProbeScheduler *s, CattaProbeJob *pj, unsigned msec, unsigned jitter) {
+    struct timeval tv;
+
+    assert(s);
+    assert(pj);
+
+    catta_elapse_time(&tv, msec, jitter);
+
+    if (pj->time_event)
+        catta_time_event_update(pj->time_event, &tv);
+    else
+        pj->time_event = catta_time_event_new(s->time_event_queue, &tv, elapse_callback, pj);
+}
+
+static void job_mark_done(CattaProbeScheduler *s, CattaProbeJob *pj) {
+    assert(s);
+    assert(pj);
+
+    assert(!pj->done);
+
+    CATTA_LLIST_REMOVE(CattaProbeJob, jobs, s->jobs, pj);
+    CATTA_LLIST_PREPEND(CattaProbeJob, jobs, s->history, pj);
+
+    pj->done = 1;
+
+    job_set_elapse_time(s, pj, CATTA_PROBE_HISTORY_MSEC, 0);
+    gettimeofday(&pj->delivery, NULL);
+}
+
+CattaProbeScheduler *catta_probe_scheduler_new(CattaInterface *i) {
+    CattaProbeScheduler *s;
+
+    assert(i);
+
+    if (!(s = catta_new(CattaProbeScheduler, 1))) {
+        catta_log_error(__FILE__": Out of memory");
+        return NULL;
+    }
+
+    s->iface = i;
+    s->time_event_queue = i->monitor->server->time_event_queue;
+
+    CATTA_LLIST_HEAD_INIT(CattaProbeJob, s->jobs);
+    CATTA_LLIST_HEAD_INIT(CattaProbeJob, s->history);
+
+    return s;
+}
+
+void catta_probe_scheduler_free(CattaProbeScheduler *s) {
+    assert(s);
+
+    catta_probe_scheduler_clear(s);
+    catta_free(s);
+}
+
+void catta_probe_scheduler_clear(CattaProbeScheduler *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(CattaProbeScheduler *s, CattaDnsPacket *p, CattaProbeJob *pj) {
+    size_t size;
+    CattaKey *k;
+    int b;
+
+    assert(s);
+    assert(p);
+    assert(pj);
+
+    assert(!pj->chosen);
+
+    /* Estimate the size for this record */
+    size =
+        catta_key_get_estimate_size(pj->record->key) +
+        catta_record_get_estimate_size(pj->record);
+
+    /* Too large */
+    if (size > catta_dns_packet_space(p))
+        return 0;
+
+    /* Create the probe query */
+    if (!(k = catta_key_new(pj->record->key->name, pj->record->key->clazz, CATTA_DNS_TYPE_ANY)))
+        return 0; /* OOM */
+
+    b = !!catta_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 || !catta_domain_equal(k->name, pj->record->key->name))
+            continue;
+
+        /* This job wouldn't fit in */
+        if (catta_record_get_estimate_size(pj->record) > catta_dns_packet_space(p))
+            break;
+
+        /* Mark this job for addition to the packet */
+        pj->chosen = 1;
+    }
+
+    catta_key_unref(k);
+
+    return 1;
+}
+
+static void elapse_callback(CATTA_GCC_UNUSED CattaTimeEvent *e, void* data) {
+    CattaProbeJob *pj = data, *next;
+    CattaProbeScheduler *s;
+    CattaDnsPacket *p;
+    unsigned n;
+
+    assert(pj);
+    s = pj->scheduler;
+
+    if (pj->done) {
+        /* Lets remove it  from the history */
+        job_free(s, pj);
+        return;
+    }
+
+    if (!(p = catta_dns_packet_new_query(s->iface->hardware->mtu)))
+        return; /* OOM */
+    n = 1;
+
+    /* Add the import probe */
+    if (!packet_add_probe_query(s, p, pj)) {
+        size_t size;
+        CattaKey *k;
+        int b;
+
+        catta_dns_packet_free(p);
+
+        /* The probe didn't fit in the package, so let's allocate a larger one */
+
+        size =
+            catta_key_get_estimate_size(pj->record->key) +
+            catta_record_get_estimate_size(pj->record) +
+            CATTA_DNS_PACKET_HEADER_SIZE;
+
+        if (!(p = catta_dns_packet_new_query(size + CATTA_DNS_PACKET_EXTRA_SIZE)))
+            return; /* OOM */
+
+        if (!(k = catta_key_new(pj->record->key->name, pj->record->key->clazz, CATTA_DNS_TYPE_ANY))) {
+            catta_dns_packet_free(p);
+            return;  /* OOM */
+        }
+
+        b = catta_dns_packet_append_key(p, k, 0) && catta_dns_packet_append_record(p, pj->record, 0, 0);
+        catta_key_unref(k);
+
+        if (b) {
+            catta_dns_packet_set_field(p, CATTA_DNS_FIELD_NSCOUNT, 1);
+            catta_dns_packet_set_field(p, CATTA_DNS_FIELD_QDCOUNT, 1);
+            catta_interface_send_packet(s->iface, p);
+        } else
+            catta_log_warn("Probe record too large, cannot send");
+
+        catta_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++;
+    }
+
+    catta_dns_packet_set_field(p, CATTA_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 (!catta_dns_packet_append_record(p, pj->record, 0, 0)) {
+/*             catta_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 ++;
+    }
+
+    catta_dns_packet_set_field(p, CATTA_DNS_FIELD_NSCOUNT, n);
+
+    /* Send it now */
+    catta_interface_send_packet(s->iface, p);
+    catta_dns_packet_free(p);
+}
+
+static CattaProbeJob* find_scheduled_job(CattaProbeScheduler *s, CattaRecord *record) {
+    CattaProbeJob *pj;
+
+    assert(s);
+    assert(record);
+
+    for (pj = s->jobs; pj; pj = pj->jobs_next) {
+        assert(!pj->done);
+
+        if (catta_record_equal_no_ttl(pj->record, record))
+            return pj;
+    }
+
+    return NULL;
+}
+
+static CattaProbeJob* find_history_job(CattaProbeScheduler *s, CattaRecord *record) {
+    CattaProbeJob *pj;
+
+    assert(s);
+    assert(record);
+
+    for (pj = s->history; pj; pj = pj->jobs_next) {
+        assert(pj->done);
+
+        if (catta_record_equal_no_ttl(pj->record, record)) {
+            /* Check whether this entry is outdated */
+
+            if (catta_age(&pj->delivery) > CATTA_PROBE_HISTORY_MSEC*1000) {
+                /* it is outdated, so let's remove it */
+                job_free(s, pj);
+                return NULL;
+            }
+
+            return pj;
+        }
+    }
+
+    return NULL;
+}
+
+int catta_probe_scheduler_post(CattaProbeScheduler *s, CattaRecord *record, int immediately) {
+    CattaProbeJob *pj;
+    struct timeval tv;
+
+    assert(s);
+    assert(record);
+    assert(!catta_key_is_pattern(record->key));
+
+    if ((pj = find_history_job(s, record)))
+        return 0;
+
+    catta_elapse_time(&tv, immediately ? 0 : CATTA_PROBE_DEFER_MSEC, 0);
+
+    if ((pj = find_scheduled_job(s, record))) {
+
+        if (catta_timeval_compare(&tv, &pj->delivery) < 0) {
+            /* If the new entry should be scheduled earlier, update the old entry */
+            pj->delivery = tv;
+            catta_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 = catta_time_event_new(s->time_event_queue, &pj->delivery, elapse_callback, pj);
+
+
+/*     catta_log_debug("Accepted new probe job."); */
+
+        return 1;
+    }
+}