diff --git a/src/knot/zone/semantic-check.c b/src/knot/zone/semantic-check.c
index 1d20993524f52d065294bc5c1118a796461a4f1b..83fb37d6d7a61686d3c2b77c99e029cf32e78835 100644
--- a/src/knot/zone/semantic-check.c
+++ b/src/knot/zone/semantic-check.c
@@ -144,7 +144,7 @@ const struct check_function check_functions[] = {
 	{check_nsec_bitmap, SEM_CHECK_NSEC | SEM_CHECK_NSEC3},
 };
 
-const int check_functions_len = sizeof(check_functions)/sizeof(struct check_function);
+const int check_functions_len = sizeof(check_functions) / sizeof(struct check_function);
 
 void err_handler_init(err_handler_t *h)
 {
@@ -164,9 +164,9 @@ void err_handler_deinit(err_handler_t *h)
 }
 
 int err_handler_node_error(err_handler_t *handler, const zone_contents_t *zone,
-			     const zone_node_t *node, int error, const char *data)
+                           const zone_node_t *node, int error, const char *data)
 {
-	err_node_t * log = malloc(sizeof(err_node_t));
+	err_node_t *log = malloc(sizeof(err_node_t));
 	if (log == NULL) {
 		return KNOT_ENOMEM;
 	}
@@ -179,7 +179,7 @@ int err_handler_node_error(err_handler_t *handler, const zone_contents_t *zone,
 
 	log->name = knot_dname_to_str_alloc(node->owner);
 	log->zone_name = knot_dname_to_str_alloc(zone->apex->owner);
-	add_tail(&handler->error_list, (node_t*)log);
+	add_tail(&handler->error_list, (node_t *)log);
 	handler->errors[-error]++;
 	handler->error_count++;
 
@@ -189,7 +189,7 @@ int err_handler_node_error(err_handler_t *handler, const zone_contents_t *zone,
 int err_handler_zone_error(err_handler_t *handler, const knot_dname_t *zname,
                            int error)
 {
-	err_node_t * log = malloc(sizeof(err_node_t));
+	err_node_t *log = malloc(sizeof(err_node_t));
 	if (log == NULL) {
 		return KNOT_ENOMEM;
 	}
@@ -199,7 +199,7 @@ int err_handler_zone_error(err_handler_t *handler, const knot_dname_t *zname,
 
 	log->zone_name = knot_dname_to_str_alloc(zname);
 
-	add_tail(&handler->error_list, (node_t*)log);
+	add_tail(&handler->error_list, (node_t *)log);
 	handler->errors[-error]++;
 	handler->error_count++;
 
@@ -280,8 +280,8 @@ static int check_rrsig_rdata(err_handler_t *handler,
 
 	if (knot_rrsig_type_covered(rrsig, 0) != rrset->type) {
 		err_handler_node_error(handler, zone, node,
-		                         ZC_ERR_RRSIG_RDATA_TYPE_COVERED,
-		                         info_str);
+		                       ZC_ERR_RRSIG_RDATA_TYPE_COVERED,
+		                       info_str);
 	}
 
 	/* label number at the 2nd index should be same as owner's */
@@ -293,13 +293,13 @@ static int check_rrsig_rdata(err_handler_t *handler,
 		/* if name has wildcard, label must not be included */
 		if (!knot_dname_is_wildcard(rrset->owner)) {
 			err_handler_node_error(handler, zone, node,
-			                         ZC_ERR_RRSIG_RDATA_LABELS,
-			                         info_str);
+			                       ZC_ERR_RRSIG_RDATA_LABELS,
+			                       info_str);
 		} else {
 			if (abs(tmp) != 1) {
 				err_handler_node_error(handler, zone, node,
-				             ZC_ERR_RRSIG_RDATA_LABELS,
-				                         info_str);
+				                       ZC_ERR_RRSIG_RDATA_LABELS,
+				                       info_str);
 			}
 		}
 	}
@@ -311,22 +311,22 @@ static int check_rrsig_rdata(err_handler_t *handler,
 	for (uint16_t i = 0; i < rr_count; ++i) {
 		if (original_ttl != knot_rdata_ttl(knot_rdataset_at(&rrset->rrs, i))) {
 			err_handler_node_error(handler, zone, node,
-			                         ZC_ERR_RRSIG_RDATA_TTL,
-			                         info_str);
+			                       ZC_ERR_RRSIG_RDATA_TTL,
+			                       info_str);
 		}
 	}
 
 	/* Check for expired signature. */
 	if (knot_rrsig_sig_expiration(rrsig, rr_pos) < time(NULL)) {
 		err_handler_node_error(handler, zone, node,
-		                         ZC_ERR_RRSIG_RDATA_EXPIRATION,
-		                         info_str);
+		                       ZC_ERR_RRSIG_RDATA_EXPIRATION,
+		                       info_str);
 	}
 
 	/* Check if DNSKEY exists. */
 	if (knot_rrset_empty(dnskey_rrset)) {
 		err_handler_node_error(handler, zone, node,
-		                         ZC_ERR_RRSIG_NO_DNSKEY, info_str);
+		                       ZC_ERR_RRSIG_NO_DNSKEY, info_str);
 	}
 
 	/* signer's name is same as in the zone apex */
@@ -336,8 +336,8 @@ static int check_rrsig_rdata(err_handler_t *handler,
 	if (!knot_rrset_empty(dnskey_rrset) &&
 	    !knot_dname_is_equal(signer, dnskey_rrset->owner)) {
 		err_handler_node_error(handler, zone, node,
-		                         ZC_ERR_RRSIG_RDATA_DNSKEY_OWNER,
-		                         info_str);
+		                       ZC_ERR_RRSIG_RDATA_DNSKEY_OWNER,
+		                       info_str);
 	}
 
 	knot_dname_free(&signer, NULL);
@@ -374,14 +374,14 @@ static int check_rrsig_rdata(err_handler_t *handler,
 			match = 1;
 		} else {
 			err_handler_node_error(handler, zone, node,
-			                         ZC_ERR_RRSIG_RDATA_SIGNED_WRONG,
-			                         "DNSKEY RDATA not matching");
+			                       ZC_ERR_RRSIG_RDATA_SIGNED_WRONG,
+			                       "DNSKEY RDATA not matching");
 		}
 	}
 
 	if (!match) {
 		err_handler_node_error(handler, zone, node,
-		                         ZC_ERR_RRSIG_NO_DNSKEY, info_str);
+		                       ZC_ERR_RRSIG_NO_DNSKEY, info_str);
 	}
 
 	return KNOT_EOK;
@@ -392,7 +392,7 @@ static void check_signed_rrsig(const zone_node_t *node, semchecks_data_t *data)
 	/* signed rrsig - nonsense */
 	if (node_rrtype_is_signed(node, KNOT_RRTYPE_RRSIG)) {
 		err_handler_node_error(data->handler, data->zone, node,
-		                         ZC_ERR_RRSIG_SIGNED, NULL);
+		                       ZC_ERR_RRSIG_SIGNED, NULL);
 	}
 }
 /*!
@@ -435,16 +435,16 @@ static int check_rrsig_in_rrset(err_handler_t *handler,
 
 	if (ret == KNOT_ENOENT) {
 		err_handler_node_error(handler, zone, node,
-		                         ZC_ERR_RRSIG_NO_RRSIG,
-		                         info_str);
+		                       ZC_ERR_RRSIG_NO_RRSIG,
+		                       info_str);
 		return KNOT_EOK;
 	}
 
 	const knot_rdata_t *sig_rr = knot_rdataset_at(&rrsigs, 0);
 	if (knot_rdata_ttl(knot_rdataset_at(&rrset->rrs, 0)) != knot_rdata_ttl(sig_rr)) {
 		err_handler_node_error(handler, zone, node,
-		                         ZC_ERR_RRSIG_TTL,
-		                         info_str);
+		                       ZC_ERR_RRSIG_TTL,
+		                       info_str);
 	}
 
 	for (uint16_t i = 0; i < (&rrsigs)->rr_count; ++i) {
@@ -460,7 +460,7 @@ static int check_rrsig_in_rrset(err_handler_t *handler,
 }
 
 /*!
- * \brief Check if glue record for delegation are presenr.
+ * \brief Check if glue record for delegation is present.
  *
  * Also check if there is NS record in the zone.
  * \param node Node to check
@@ -474,8 +474,7 @@ static void check_delegation(const zone_node_t *node, semchecks_data_t *data)
 	const knot_rdataset_t *ns_rrs = node_rdataset(node, KNOT_RRTYPE_NS);
 	if (ns_rrs == NULL) {
 		err_handler_node_error(data->handler, data->zone, node,
-		                         ZC_ERR_MISSING_NS_DEL_POINT,
-		                         NULL);
+		                       ZC_ERR_MISSING_NS_DEL_POINT, NULL);
 		return;
 	}
 
@@ -500,9 +499,8 @@ static void check_delegation(const zone_node_t *node, semchecks_data_t *data)
 			const zone_node_t *wildcard_node =
 				zone_contents_find_node(data->zone, wildcard);
 			if (wildcard_node == NULL) {
-				err_handler_node_error(
-					data->handler, data->zone, node,
-					ZC_ERR_GLUE_NODE, NULL);
+				err_handler_node_error(data->handler, data->zone,
+				                       node, ZC_ERR_GLUE_NODE, NULL);
 				// Cannot continue
 				return;
 			}
@@ -511,7 +509,7 @@ static void check_delegation(const zone_node_t *node, semchecks_data_t *data)
 		if (!node_rrtype_exists(glue_node, KNOT_RRTYPE_A) &&
 		    !node_rrtype_exists(glue_node, KNOT_RRTYPE_AAAA)) {
 			err_handler_node_error(data->handler, data->zone,
-			                         node, ZC_ERR_GLUE_RECORD, NULL);
+			                       node, ZC_ERR_GLUE_RECORD, NULL);
 		}
 	}
 }
@@ -551,7 +549,7 @@ static void check_rrsig(const zone_node_t *node, semchecks_data_t *data)
  * \brief Add all RR types from a node into the bitmap.
  */
 inline static void bitmap_add_all_node_rrsets(dnssec_nsec_bitmap_t *bitmap,
-                                          const zone_node_t *node)
+                                              const zone_node_t *node)
 {
 	bool deleg = node->flags && NODE_FLAGS_DELEG;
 	for (int i = 0; i < node->rrset_count; i++) {
@@ -596,7 +594,7 @@ static void check_nsec_bitmap(const zone_node_t *node, semchecks_data_t *data)
 	// create NSEC bitmap from node
 	dnssec_nsec_bitmap_t *node_bitmap = dnssec_nsec_bitmap_new();
 	if (node_bitmap == NULL) {
-		return ;
+		return;
 	}
 	bitmap_add_all_node_rrsets(node_bitmap, node);
 
@@ -620,9 +618,9 @@ static void check_nsec_bitmap(const zone_node_t *node, semchecks_data_t *data)
 	if (node_wire_size != nsec_wire_size ||
 	    memcmp(node_wire, nsec_wire, node_wire_size) != 0) {
 		err_handler_node_error(data->handler,
-		                         data->zone, node,
-		                         ZC_ERR_NSEC_RDATA_BITMAP,
-		                         NULL);
+		                       data->zone, node,
+		                       ZC_ERR_NSEC_RDATA_BITMAP,
+		                       NULL);
 	}
 
 	free(node_wire);
@@ -643,26 +641,25 @@ static void check_nsec(const zone_node_t *node, semchecks_data_t *data)
 	}
 
 	/* check for NSEC record */
-	const knot_rdataset_t *nsec_rrs =
-		node_rdataset(node, KNOT_RRTYPE_NSEC);
+	const knot_rdataset_t *nsec_rrs = node_rdataset(node, KNOT_RRTYPE_NSEC);
 	if (nsec_rrs == NULL) {
 		err_handler_node_error(data->handler, data->zone, node,
-		                         ZC_ERR_NO_NSEC, NULL);
+		                       ZC_ERR_NO_NSEC, NULL);
 		return;
 	}
 
 	/* Test that only one record is in the NSEC RRSet */
 	if (nsec_rrs->rr_count != 1) {
 		err_handler_node_error(data->handler,
-		                         data->zone, node,
-		                         ZC_ERR_NSEC_RDATA_MULTIPLE,
-		                         NULL);
+		                       data->zone, node,
+		                       ZC_ERR_NSEC_RDATA_MULTIPLE,
+		                       NULL);
 	}
 
-	if (data->next_nsec != node ) {
+	if (data->next_nsec != node) {
 		err_handler_node_error(data->handler, data->zone, node,
-		                         ZC_ERR_NSEC_RDATA_CHAIN,
-		                         NULL);
+		                       ZC_ERR_NSEC_RDATA_CHAIN,
+		                       NULL);
 	}
 
 	/*
@@ -678,8 +675,8 @@ static void check_nsec(const zone_node_t *node, semchecks_data_t *data)
 
 	if (data->next_nsec == NULL) {
 		err_handler_node_error(data->handler, data->zone, node,
-		                         ZC_ERR_NSEC_RDATA_CHAIN,
-		                         NULL);
+		                       ZC_ERR_NSEC_RDATA_CHAIN,
+		                       NULL);
 	}
 }
 
@@ -699,9 +696,8 @@ static void check_nsec3_opt_out(const zone_node_t *node, semchecks_data_t *data)
 	/* I know it's probably not what RFCs say, but it will have to
 	 * do for now. */
 	if (node_rrtype_exists(node, KNOT_RRTYPE_DS)) {
-		err_handler_node_error(
-				data->handler, data->zone, node,
-				ZC_ERR_NSEC3_UNSECURED_DELEGATION, NULL);
+		err_handler_node_error(data->handler, data->zone, node,
+		                       ZC_ERR_NSEC3_UNSECURED_DELEGATION, NULL);
 		return;
 	} else {
 		/* Unsecured delegation, check whether it is part of
@@ -713,9 +709,9 @@ static void check_nsec3_opt_out(const zone_node_t *node, semchecks_data_t *data)
 		                                      &nsec3_node,
 		                                      &nsec3_previous) != ZONE_NAME_NOT_FOUND) {
 			err_handler_node_error(data->handler,
-			                         data->zone, node,
-			                         ZC_ERR_NSEC3_NOT_FOUND,
-			                         NULL);
+			                       data->zone, node,
+			                       ZC_ERR_NSEC3_NOT_FOUND,
+			                       NULL);
 			return;
 		}
 		assert(nsec3_previous);
@@ -733,10 +729,9 @@ static void check_nsec3_opt_out(const zone_node_t *node, semchecks_data_t *data)
 			// opt-out no need to check more
 			return;
 		} else {
-			err_handler_node_error(data->handler,
-				data->zone, node,
-				ZC_ERR_NSEC3_UNSECURED_DELEGATION_OPT,
-				NULL);
+			err_handler_node_error(data->handler, data->zone, node,
+			                       ZC_ERR_NSEC3_UNSECURED_DELEGATION_OPT,
+			                       NULL);
 			/* We cannot continue from here. */
 			return;
 		}
@@ -754,10 +749,10 @@ static void check_nsec3_opt_out(const zone_node_t *node, semchecks_data_t *data)
 static void check_nsec3(const zone_node_t *node, semchecks_data_t *data)
 {
 	assert(node);
-	bool auth = !(node->flags & NODE_FLAGS_NONAUTH);
-	bool deleg = (node->flags & NODE_FLAGS_DELEG);
+	bool auth = (node->flags & NODE_FLAGS_NONAUTH) == 0;
+	bool deleg = (node->flags & NODE_FLAGS_DELEG) != 0;
 
-	if (!(auth || deleg)) {
+	if (!auth && !deleg) {
 		return;
 	}
 
@@ -770,7 +765,7 @@ static void check_nsec3(const zone_node_t *node, semchecks_data_t *data)
 	                                            KNOT_RRTYPE_NSEC3);
 	if (nsec3_rrs == NULL) {
 		err_handler_node_error(data->handler, data->zone, node,
-		                         ZC_ERR_NSEC3_RDATA_CHAIN, NULL);
+		                       ZC_ERR_NSEC3_RDATA_CHAIN, NULL);
 		return;
 	}
 
@@ -780,7 +775,7 @@ static void check_nsec3(const zone_node_t *node, semchecks_data_t *data)
 	uint32_t minimum_ttl = knot_soa_minimum(soa_rrs);
 	if (knot_rdata_ttl(nsec3_rr) != minimum_ttl) {
 		err_handler_node_error(data->handler, data->zone, node,
-		                         ZC_ERR_NSEC3_RDATA_TTL, NULL);
+		                       ZC_ERR_NSEC3_RDATA_TTL, NULL);
 	}
 
 	/* Get next nsec3 node */
@@ -803,10 +798,10 @@ static void check_nsec3(const zone_node_t *node, semchecks_data_t *data)
 
 	if (next_nsec3 == NULL) {
 		err_handler_node_error(data->handler, data->zone, node,
-		                         ZC_ERR_NSEC3_RDATA_CHAIN, NULL);
+		                       ZC_ERR_NSEC3_RDATA_CHAIN, NULL);
 	} else if (next_nsec3->prev != nsec3_node) {
 		err_handler_node_error(data->handler, data->zone, node,
-		                         ZC_ERR_NSEC3_RDATA_CHAIN, NULL);
+		                       ZC_ERR_NSEC3_RDATA_CHAIN, NULL);
 	}
 
 	/* Check that the node only contains NSEC3 and RRSIG. */
@@ -816,8 +811,7 @@ static void check_nsec3(const zone_node_t *node, semchecks_data_t *data)
 		if (!(type == KNOT_RRTYPE_NSEC3 ||
 		    type == KNOT_RRTYPE_RRSIG)) {
 			err_handler_node_error(data->handler, data->zone, nsec3_node,
-			                         ZC_ERR_NSEC3_EXTRA_RECORD,
-			                         NULL);
+			                       ZC_ERR_NSEC3_EXTRA_RECORD, NULL);
 		}
 	}
 }
@@ -854,7 +848,7 @@ static void check_cname_multiple(const zone_node_t *node, semchecks_data_t *data
 	if (cname_rrs->rr_count != 1) {
 		data->fatal_error = true;
 		err_handler_node_error(data->handler, data->zone, node,
-		                         ZC_ERR_CNAME_MULTIPLE, NULL);
+		                       ZC_ERR_CNAME_MULTIPLE, NULL);
 	}
 }
 
@@ -871,15 +865,15 @@ static void check_dname(const zone_node_t *node, semchecks_data_t *data)
 	if (dname_rrs != NULL && node->children != 0) {
 		data->fatal_error = true;
 		err_handler_node_error(data->handler, data->zone, node,
-		                         ZC_ERR_DNAME_CHILDREN,
-		                         "error triggered by parent node");
+		                       ZC_ERR_DNAME_CHILDREN,
+		                       "error triggered by parent node");
 	}
 
 	if (node->parent != NULL && node_rrtype_exists(node->parent, KNOT_RRTYPE_DNAME)) {
 		data->fatal_error = true;
 		err_handler_node_error(data->handler, data->zone, node,
-		                         ZC_ERR_DNAME_CHILDREN,
-		                         "error triggered by child node");
+		                       ZC_ERR_DNAME_CHILDREN,
+		                       "error triggered by child node");
 	}
 }
 
@@ -893,14 +887,14 @@ static void check_nsec_cyclic(semchecks_data_t *data)
 {
 	if (data->next_nsec == NULL) {
 		err_handler_node_error(data->handler, data->zone,
-		                         data->zone->apex,
-		                         ZC_ERR_NSEC_RDATA_CHAIN_NOT_CYCLIC, NULL);
+		                       data->zone->apex,
+		                       ZC_ERR_NSEC_RDATA_CHAIN_NOT_CYCLIC, NULL);
 		return;
 	}
 
 	if (!knot_dname_is_equal(data->next_nsec->owner, data->zone->apex->owner)) {
 		err_handler_node_error(data->handler, data->zone, data->next_nsec,
-		                         ZC_ERR_NSEC_RDATA_CHAIN_NOT_CYCLIC, NULL);
+		                       ZC_ERR_NSEC_RDATA_CHAIN_NOT_CYCLIC, NULL);
 		return;
 	}
 }
diff --git a/src/knot/zone/semantic-check.h b/src/knot/zone/semantic-check.h
index 3254741295f3c4e433e6ab8ed3bd6c1e07137eea..04290194bff8ceae895511a05bdc63bc2ec8b105 100644
--- a/src/knot/zone/semantic-check.h
+++ b/src/knot/zone/semantic-check.h
@@ -29,7 +29,6 @@
 #include "contrib/ucw/lists.h"
 #include "libknot/mm_ctx.h"
 
-
 enum check_levels {
 	SEM_CHECK_MANDATORY = 1 << 0,
 	SEM_CHECK_OPTIONAL =  1 << 1,