zone contents: cleanup of changeset-related functions, comments

src/knot/updates/changesets.c

@@ -178,8 +178,8 @@ static bool need_to_insert(zone_contents_t *counterpart, const knot_rrset_t *rr)
 
 	if (node->rrset_count == 0) {
 		// Remove empty node.
-		zone_tree_t *t = zone_contents_rrset_is_nsec3rel(rr) ? counterpart->nsec3_nodes :
-		                                                   counterpart->nodes;
+		zone_tree_t *t = knot_rrset_is_nsec3rel(rr) ?
+		                     counterpart->nsec3_nodes : counterpart->nodes;
 		zone_contents_delete_empty_node(counterpart, t, node);
 	}
 

src/knot/zone/contents.c

@@ -643,18 +643,61 @@ static int recreate_nsec3_tree(const zone_contents_t *z, zone_contents_t *out)
 	return KNOT_EOK;
 }
 
-bool zone_contents_rrset_is_nsec3rel(const knot_rrset_t *rr)
+static zone_node_t *get_previous(const zone_contents_t *zone,
+                                 const knot_dname_t *name)
 {
-	if (rr == NULL) {
-		return false;
+	if (zone == NULL || name == NULL) {
+		return NULL;
+	}
+
+	zone_node_t *found = NULL, *prev = NULL;
+
+	int exact_match = find_in_tree(zone->nodes, name, &found, &prev);
+	assert(exact_match >= 0);
+	//assert(prev != NULL);
+
+	return prev;
+}
+
+static zone_node_t *zone_contents_get_greatest_child(const zone_contents_t *zone, const knot_dname_t *parent)
+{
+	if (knot_dname_size(parent) + 2 > KNOT_DNAME_MAXLEN) {
+		// Not enough space for children.
+		return NULL;
+	}
+
+	knot_dname_t dn[KNOT_DNAME_MAXLEN] = { 0x01, 0xff };
+	knot_dname_to_wire(dn + 2, parent, KNOT_DNAME_MAXLEN);
+	zone_node_t *child = get_node(zone, dn);
+	if (child) {
+		return child;
 	}
 
-	/* Is NSEC3 or non-empty RRSIG covering NSEC3. */
-	return ((rr->type == KNOT_RRTYPE_NSEC3) ||
-	        (rr->type == KNOT_RRTYPE_RRSIG
-	         && knot_rrsig_type_covered(&rr->rrs, 0) == KNOT_RRTYPE_NSEC3));
+	child = get_previous(zone, dn);
+	if (!child) {
+		return NULL;
+	}
+	//assert(child);
+	const int parent_labels = knot_dname_labels(parent, NULL);
+	const int child_labels = knot_dname_labels(child->owner, NULL);
+	if (child_labels <= parent_labels) {
+		return NULL;
+	}
+
+	if (knot_dname_matched_labels(parent, child->owner) != parent_labels) {
+		return NULL;
+	}
+
+	return child;
+}
+
+static bool contents_has_children(const zone_contents_t *zone, const knot_dname_t *owner)
+{
+	return zone_contents_get_greatest_child(zone, owner) != NULL;
 }
 
+// Public API
+
 int zone_contents_add_rr(zone_contents_t *z, const knot_rrset_t *rr,
                          zone_node_t **n)
 {
@@ -662,15 +705,82 @@ int zone_contents_add_rr(zone_contents_t *z, const knot_rrset_t *rr,
 		return KNOT_EINVAL;
 	}
 
-	return insert_rr(z, rr, n, zone_contents_rrset_is_nsec3rel(rr));
+	return insert_rr(z, rr, n, knot_rrset_is_nsec3rel(rr));
+}
+
+zone_node_t *zone_contents_get_node_for_rr(zone_contents_t *zone, const knot_rrset_t *rrset)
+{
+	if (zone == NULL || rrset == NULL) {
+		return NULL;
+	}
+
+	const bool nsec3 = knot_rrset_is_nsec3rel(rrset);
+	zone_node_t *node = nsec3 ? get_nsec3_node(zone, rrset->owner) :
+	                            get_node(zone, rrset->owner);
+	if (node == NULL) {
+		node = node_new(rrset->owner, NULL);
+		int ret = nsec3 ? add_nsec3_node(zone, node) : add_node(zone, node, 1);
+		if (ret != KNOT_EOK) {
+			node_free(&node, NULL);
+			return NULL;
+		}
+
+		return node;
+	} else {
+		return node;
+	}
+}
+
+int zone_contents_delete_empty_node(zone_contents_t *contents, zone_tree_t *tree, zone_node_t *node)
+{
+	if (!contents || !tree || !node) {
+		return KNOT_EINVAL;
+	}
+
+	if (node->rrset_count == 0 && !contents_has_children(contents, node->owner)) {
+		const knot_dname_t *parent_dname = knot_wire_next_label(node->owner, NULL);
+		zone_node_t *parent_node = NULL;
+		if (tree == contents->nsec3_nodes) {
+			// Only one level in NSEC3 tree
+			parent_node = (node == contents->apex) ? NULL : contents->apex;
+		} else {
+			parent_node = (zone_node_t *) zone_contents_find_node(contents, parent_dname);
+		}
+
+		if (parent_node && parent_node != contents->apex) {
+			// Recurse using the parent node, do not delete possibly empty parent.
+			int ret = zone_contents_delete_empty_node(contents, tree, parent_node);
+			if (ret != KNOT_EOK) {
+				return ret;
+			}
+		}
+
+		// Delete node
+		zone_node_t *removed_node = NULL;
+		zone_tree_remove(tree, node->owner, &removed_node);
+		UNUSED(removed_node);
+		node_free(&node, NULL);
+	}
+
+	return KNOT_EOK;
 }
 
-const zone_node_t *zone_contents_find_node(const zone_contents_t *zone,
-                                           const knot_dname_t *name)
+const zone_node_t *zone_contents_find_node(const zone_contents_t *zone, const knot_dname_t *name)
 {
 	return get_node(zone, name);
 }
 
+zone_node_t *zone_contents_find_node_for_rr(zone_contents_t *contents, const knot_rrset_t *rrset)
+{
+	if (contents == NULL || rrset == NULL) {
+		return NULL;
+	}
+
+	const bool nsec3 = knot_rrset_is_nsec3rel(rrset);
+	return nsec3 ? get_nsec3_node(contents, rrset->owner) :
+	               get_node(contents, rrset->owner);
+}
+
 int zone_contents_find_dname(const zone_contents_t *zone,
                              const knot_dname_t *name,
                              const zone_node_t **node,
@@ -723,22 +833,6 @@ int zone_contents_find_dname(const zone_contents_t *zone,
 	return exact_match ? ZONE_NAME_FOUND : ZONE_NAME_NOT_FOUND;
 }
 
-static zone_node_t *get_previous(const zone_contents_t *zone,
-                                 const knot_dname_t *name)
-{
-	if (zone == NULL || name == NULL) {
-		return NULL;
-	}
-
-	zone_node_t *found = NULL, *prev = NULL;
-
-	int exact_match = find_in_tree(zone->nodes, name, &found, &prev);
-	assert(exact_match >= 0);
-	//assert(prev != NULL);
-
-	return prev;
-}
-
 const zone_node_t *zone_contents_find_previous(const zone_contents_t *zone,
                                                const knot_dname_t *name)
 {
@@ -1100,102 +1194,3 @@ bool zone_contents_is_empty(const zone_contents_t *zone)
 {
 	return !zone || !node_rrtype_exists(zone->apex, KNOT_RRTYPE_SOA);
 }
-
-zone_node_t *zone_contents_get_node_for_rr(zone_contents_t *zone, const knot_rrset_t *rrset)
-{
-	if (zone == NULL || rrset == NULL) {
-		return NULL;
-	}
-
-	const bool nsec3 = zone_contents_rrset_is_nsec3rel(rrset);
-	zone_node_t *node = nsec3 ? get_nsec3_node(zone, rrset->owner) :
-	                            get_node(zone, rrset->owner);
-	if (node == NULL) {
-		node = node_new(rrset->owner, NULL);
-		int ret = nsec3 ? add_nsec3_node(zone, node) : add_node(zone, node, 1);
-		if (ret != KNOT_EOK) {
-			node_free(&node, NULL);
-			return NULL;
-		}
-
-		return node;
-	} else {
-		return node;
-	}
-}
-
-zone_node_t *zone_contents_find_node_for_rr(zone_contents_t *zone, const knot_rrset_t *rrset)
-{
-	if (zone == NULL || rrset == NULL) {
-		return NULL;
-	}
-
-	const bool nsec3 = zone_contents_rrset_is_nsec3rel(rrset);
-	return nsec3 ? get_nsec3_node(zone, rrset->owner) :
-	               get_node(zone, rrset->owner);
-}
-
-zone_node_t *zone_contents_greatest_child(const zone_contents_t *zone, const knot_dname_t *parent)
-{
-	if (knot_dname_size(parent) + 2 > KNOT_DNAME_MAXLEN) {
-		// Not enough space for children.
-		return NULL;
-	}
-
-	knot_dname_t dn[KNOT_DNAME_MAXLEN] = { 0x01, 0xff };
-	knot_dname_to_wire(dn + 2, parent, KNOT_DNAME_MAXLEN);
-	zone_node_t *child = get_node(zone, dn);
-	if (child) {
-		return child;
-	}
-
-	child = get_previous(zone, dn);
-	if (!child) {
-		return NULL;
-	}
-	//assert(child);
-	const int parent_labels = knot_dname_labels(parent, NULL);
-	const int child_labels = knot_dname_labels(child->owner, NULL);
-	if (child_labels <= parent_labels) {
-		return NULL;
-	}
-
-	if (knot_dname_matched_labels(parent, child->owner) != parent_labels) {
-		return NULL;
-	}
-
-	return child;
-}
-
-static bool contents_has_children(const zone_contents_t *zone, const knot_dname_t *owner)
-{
-	return zone_contents_greatest_child(zone, owner) != NULL;
-}
-
-void zone_contents_delete_empty_node(zone_contents_t *zone, zone_tree_t *tree, zone_node_t *node)
-{
-	assert(zone);
-	assert(tree);
-	assert(node);
-	if (node->rrset_count == 0 && !contents_has_children(zone, node->owner)) {
-		const knot_dname_t *parent_dname = knot_wire_next_label(node->owner, NULL);
-		zone_node_t *parent_node = NULL;
-		if (tree == zone->nsec3_nodes) {
-			// Only one level in NSEC3 tree
-			parent_node = (node == zone->apex) ? NULL : zone->apex;
-		} else {
-			parent_node = zone_contents_find_node(zone, parent_dname);
-		}
-		if (parent_node && parent_node != zone->apex) {
-			// Recurse using the parent node, do not delete possibly empty parent.
-			zone_contents_delete_empty_node(zone, tree, parent_node);
-		}
-
-		// Delete node
-		zone_node_t *removed_node = NULL;
-		zone_tree_remove(tree, node->owner, &removed_node);
-		UNUSED(removed_node);
-		node_free(&node, NULL);
-	}
-}
-

src/knot/zone/contents.h

@@ -48,13 +48,46 @@ typedef struct zone_contents {
  */
 typedef int (*zone_contents_apply_cb_t)(zone_node_t *node, void *data);
 
+/*!
+ * \brief Allocate and create new zone contents.
+ *
+ * \param apex_name  Name of the root node.
+ *
+ * \return New contents or NULL on error.
+ */
 zone_contents_t *zone_contents_new(const knot_dname_t *apex_name);
 
+/*!
+ * \brief Add an RR to contents.
+ *
+ * \param z   Contents to add to.
+ * \param rr  The RR to add.
+ * \param n   Node to which the RR has been added to on success, unchanged otherwise.
+ *
+ * \return KNOT_E*
+ */
+int zone_contents_add_rr(zone_contents_t *z, const knot_rrset_t *rr, zone_node_t **n);
 
-bool zone_contents_rrset_is_nsec3rel(const knot_rrset_t *rr);
-
+/*!
+ * \brief Get the node with this RR (the RR's owner).
+ *
+ * \param zone   Contents to add to.
+ * \param rrset  The RR to add.
+ *
+ * \return The searched node if it exists, a new added empty node or NULL on error.
+ */
+zone_node_t *zone_contents_get_node_for_rr(zone_contents_t *zone, const knot_rrset_t *rrset);
 
-int zone_contents_add_rr(zone_contents_t *z, const knot_rrset_t *rr, zone_node_t **n);
+/*!
+ * \brief Delete a node that has no RRSets and no children.
+ *
+ * \param contents  Contents to delete from.
+ * \param tree      The tree to remove from.
+ * \param node      The node to remove.
+ *
+ * \return KNOT_E*.
+ */
+int zone_contents_delete_empty_node(zone_contents_t *contents, zone_tree_t *tree, zone_node_t *node);
 
 /*!
  * \brief Tries to find a node with the specified name in the zone.
@@ -67,8 +100,9 @@ int zone_contents_add_rr(zone_contents_t *z, const knot_rrset_t *rr, zone_node_t
  *
  * \return Corresponding node if found, NULL otherwise.
  */
-const zone_node_t *zone_contents_find_node(const zone_contents_t *contents,
-                                           const knot_dname_t *name);
+const zone_node_t *zone_contents_find_node(const zone_contents_t *contents, const knot_dname_t *name);
+
+zone_node_t *zone_contents_find_node_for_rr(zone_contents_t *contents, const knot_rrset_t *rrset);
 
 /*!
  * \brief Tries to find a node by owner in the zone contents.
@@ -249,8 +283,18 @@ int zone_contents_nsec3_apply_inorder(zone_contents_t *zone,
  */
 int zone_contents_shallow_copy(const zone_contents_t *from, zone_contents_t **to);
 
+/*!
+ * \brief Deallocate directly owned data of zone contents.
+ *
+ * \param contents  Zone contents to free.
+ */
 void zone_contents_free(zone_contents_t **contents);
 
+/*!
+ * \brief Deallocate node RRSets inside the trees, then call zone_contents_free.
+ *
+ * \param contents  Zone contents to free.
+ */
 void zone_contents_deep_free(zone_contents_t **contents);
 
 /*!
@@ -272,9 +316,4 @@ bool zone_contents_is_signed(const zone_contents_t *zone);
  */
 bool zone_contents_is_empty(const zone_contents_t *zone);
 
-zone_node_t *zone_contents_get_node_for_rr(zone_contents_t *zone, const knot_rrset_t *rrset);
-
-zone_node_t *zone_contents_find_node_for_rr(zone_contents_t *zone, const knot_rrset_t *rrset);
-
-void zone_contents_delete_empty_node(zone_contents_t *zone, zone_tree_t *tree, zone_node_t *node);
 /*! @} */

src/libknot/rrset.c

@@ -26,6 +26,7 @@
 #include "libknot/internal/mempattern.h"
 #include "libknot/rrset.h"
 #include "libknot/rrtype/naptr.h"
+#include "libknot/rrtype/rrsig.h"
 
 _public_
 knot_rrset_t *knot_rrset_new(const knot_dname_t *owner, uint16_t type,
@@ -168,6 +169,19 @@ uint32_t knot_rrset_ttl(const knot_rrset_t *rrset)
 	return knot_rdata_ttl(knot_rdataset_at(&(rrset->rrs), 0));
 }
 
+_public_
+bool knot_rrset_is_nsec3rel(const knot_rrset_t *rr)
+{
+	if (rr == NULL) {
+		return false;
+	}
+
+	/* Is NSEC3 or non-empty RRSIG covering NSEC3. */
+	return ((rr->type == KNOT_RRTYPE_NSEC3) ||
+	        (rr->type == KNOT_RRTYPE_RRSIG
+	         && knot_rrsig_type_covered(&rr->rrs, 0) == KNOT_RRTYPE_NSEC3));
+}
+
 _public_
 int knot_rrset_rr_to_canonical(knot_rrset_t *rrset)
 {

src/libknot/rrset.h

@@ -175,6 +175,12 @@ bool knot_rrset_empty(const knot_rrset_t *rrset);
  */
 uint32_t knot_rrset_ttl(const knot_rrset_t *rrset);
 
+/*!
+ * \brief Return whether the RR type is NSEC3 related (NSEC3 or RRSIG).
+ */
+bool knot_rrset_is_nsec3rel(const knot_rrset_t *rr);
+
+
 /*!
  * \brief Convert one RR into canonical format.
  *