From 74840ec50befe691261b46e4f919448587f993b7 Mon Sep 17 00:00:00 2001
From: Diego Fronza <diego@isc.org>
Date: Sat, 28 Nov 2020 18:10:35 -0300
Subject: [PATCH] Added dns_view_staleanswerenabled() function

Since it takes a couple lines of code to check whether stale answers
are enabled for a given view, code was extracted out to a proper
function.
---
 lib/dns/include/dns/view.h  |  9 +++++++++
 lib/dns/view.c              | 22 ++++++++++++++++++++++
 lib/dns/win32/libdns.def.in |  1 +
 lib/ns/query.c              | 16 +++-------------
 4 files changed, 35 insertions(+), 13 deletions(-)

diff --git a/lib/dns/include/dns/view.h b/lib/dns/include/dns/view.h
index ff72c8b758..1da372a89a 100644
--- a/lib/dns/include/dns/view.h
+++ b/lib/dns/include/dns/view.h
@@ -1343,6 +1343,15 @@ dns_view_setviewrevert(dns_view_t *view);
  *\li	'view' to be valid.
  */
 
+bool
+dns_view_staleanswerenabled(dns_view_t *view);
+/*%<
+ * Check if stale answers are enabled for this view.
+ *
+ * Requires:
+ *\li	'view' to be valid.
+ */
+
 ISC_LANG_ENDDECLS
 
 #endif /* DNS_VIEW_H */
diff --git a/lib/dns/view.c b/lib/dns/view.c
index 42c17dc6da..3572cec04a 100644
--- a/lib/dns/view.c
+++ b/lib/dns/view.c
@@ -2518,3 +2518,25 @@ dns_view_setviewrevert(dns_view_t *view) {
 		dns_zt_setviewrevert(zonetable);
 	}
 }
+
+bool
+dns_view_staleanswerenabled(dns_view_t *view) {
+	uint32_t stale_ttl = 0;
+	bool result = false;
+
+	REQUIRE(DNS_VIEW_VALID(view));
+
+	if (dns_db_getservestalettl(view->cachedb, &stale_ttl) != ISC_R_SUCCESS)
+	{
+		return (false);
+	}
+	if (stale_ttl > 0) {
+		if (view->staleanswersok == dns_stale_answer_yes) {
+			result = true;
+		} else if (view->staleanswersok == dns_stale_answer_conf) {
+			result = view->staleanswersenable;
+		}
+	}
+
+	return (result);
+}
diff --git a/lib/dns/win32/libdns.def.in b/lib/dns/win32/libdns.def.in
index c9b4e1fe80..917484d1ec 100644
--- a/lib/dns/win32/libdns.def.in
+++ b/lib/dns/win32/libdns.def.in
@@ -1147,6 +1147,7 @@ dns_view_setrootdelonly
 dns_view_setviewcommit
 dns_view_setviewrevert
 dns_view_simplefind
+dns_view_staleanswerenabled
 dns_view_thaw
 dns_view_untrust
 dns_view_weakattach
diff --git a/lib/ns/query.c b/lib/ns/query.c
index ae0a7bef4b..a8712f3a99 100644
--- a/lib/ns/query.c
+++ b/lib/ns/query.c
@@ -5581,7 +5581,6 @@ query_lookup(query_ctx_t *qctx) {
 	dns_clientinfo_t ci;
 	dns_name_t *rpzqname = NULL;
 	unsigned int dboptions;
-	dns_ttl_t stale_ttl = 0;
 	dns_ttl_t stale_refresh = 0;
 	bool dbfind_stale = false;
 
@@ -5644,18 +5643,9 @@ query_lookup(query_ctx_t *qctx) {
 
 	(void)dns_db_getservestalerefresh(qctx->client->view->cachedb,
 					  &stale_refresh);
-	(void)dns_db_getservestalettl(qctx->client->view->cachedb, &stale_ttl);
-	if (stale_refresh > 0) {
-		if (qctx->client->view->staleanswersok == dns_stale_answer_yes)
-		{
-			dboptions |= DNS_DBFIND_STALEENABLED;
-		} else if (qctx->client->view->staleanswersok ==
-			   dns_stale_answer_conf) {
-			if (qctx->client->view->staleanswersenable &&
-			    stale_ttl > 0) {
-				dboptions |= DNS_DBFIND_STALEENABLED;
-			}
-		}
+	if (stale_refresh > 0 &&
+	    dns_view_staleanswerenabled(qctx->client->view)) {
+		dboptions |= DNS_DBFIND_STALEENABLED;
 	}
 
 	result = dns_db_findext(qctx->db, rpzqname, qctx->version, qctx->type,