zone: support for zone-in-journal

src/knot/zone/zone-load.c

@@ -173,6 +173,40 @@ int zone_load_journal(conf_t *conf, zone_t *zone, zone_contents_t *contents)
 	return ret;
 }
 
+int zone_load_from_journal(conf_t *conf, zone_t *zone, zone_contents_t **contents)
+{
+	if (conf == NULL || zone == NULL || contents == NULL) {
+		return KNOT_EINVAL;
+	}
+
+	list_t chgs;
+	init_list(&chgs);
+	int ret = zone_in_journal_load(conf, zone, &chgs);
+	if (ret != KNOT_EOK) {
+		changesets_free(&chgs);
+		return ret; // include ENOENT, which is normal operation
+	}
+
+	changeset_t *boo_ch = (changeset_t *)HEAD(chgs);
+	rem_node(&boo_ch->n);
+	*contents = changeset_to_contents(boo_ch);
+
+	apply_ctx_t a_ctx = { 0 };
+	apply_init_ctx(&a_ctx, *contents, 0);
+	ret = apply_changesets_directly(&a_ctx, &chgs);
+	if (ret == KNOT_EOK) {
+		log_zone_info(zone->name, "zone loaded from journal, serial %u",
+		              zone_contents_serial(*contents));
+	} else {
+		log_zone_error(zone->name, "failed to load zone from journal (%s)",
+		               knot_strerror(ret));
+	}
+	update_cleanup(&a_ctx);
+	changesets_free(&chgs);
+
+	return ret;
+}
+
 int zone_load_post(conf_t *conf, zone_t *zone, zone_contents_t *contents,
                    uint32_t *dnssec_refresh)
 {

src/knot/zone/zone-load.h

@@ -42,6 +42,17 @@ int zone_load_contents(conf_t *conf, const knot_dname_t *zone_name,
  */
 int zone_load_journal(conf_t *conf, zone_t *zone, zone_contents_t *contents);
 
+/*!
+ * \brief Load zone contents from journal (headless).
+ *
+ * \param conf
+ * \param zone
+ * \param contents
+ * \return KNOT_EOK or an error
+ */
+int zone_load_from_journal(conf_t *conf, zone_t *zone,
+                           zone_contents_t **contents);
+
 /*!
  * \brief Zone loading post-actions (zone resign, calculation of delta)
  *

src/knot/zone/zone.c

@@ -313,6 +313,25 @@ int zone_changes_load(conf_t *conf, zone_t *zone, list_t *dst, uint32_t from)
 	return ret;
 }
 
+int zone_in_journal_load(conf_t *conf, zone_t *zone, list_t *dst)
+{
+	if (conf == NULL || zone == NULL || dst == NULL) {
+		return KNOT_EINVAL;
+	}
+
+	int ret = KNOT_ENOENT;
+
+	if (journal_exists(zone->journal_db, zone->name)) {
+		ret = open_journal(zone);
+	}
+
+	if (ret == KNOT_EOK) {
+		ret = journal_load_bootstrap(zone->journal, dst);
+	}
+
+	return ret;
+}
+
 int zone_flush_journal(conf_t *conf, zone_t *zone)
 {
 	if (conf == NULL || zone == NULL) {

src/knot/zone/zone.h

@@ -132,6 +132,7 @@ void zone_control_clear(zone_t *zone);
 int zone_change_store(conf_t *conf, zone_t *zone, changeset_t *change);
 int zone_changes_store(conf_t *conf, zone_t *zone, list_t *chgs);
 int zone_changes_load(conf_t *conf, zone_t *zone, list_t *dst, uint32_t from);
+int zone_in_journal_load(conf_t *conf, zone_t *zone, list_t *dst);
 
 /*! \brief Synchronize zone file with journal. */
 int zone_flush_journal(conf_t *conf, zone_t *zone);