From f7f543d99bcb7008808e0c55e35ccd6788cb32a7 Mon Sep 17 00:00:00 2001
From: Matthijs Mekking <matthijs@isc.org>
Date: Thu, 27 May 2021 09:43:21 +0200
Subject: [PATCH] Reuse rdatset->ttl when dumping ancient RRsets

Rather than having an expensive 'expired' (fka 'stale_ttl') in the
rdataset structure, that is only used to be printed in a comment on
ancient RRsets, reuse the TTL field of the RRset.
---
 lib/dns/include/dns/rdataset.h | 7 -------
 lib/dns/masterdump.c           | 4 ++--
 lib/dns/rbtdb.c                | 4 +---
 3 files changed, 3 insertions(+), 12 deletions(-)

diff --git a/lib/dns/include/dns/rdataset.h b/lib/dns/include/dns/rdataset.h
index 906edd0aa3..2569e40d23 100644
--- a/lib/dns/include/dns/rdataset.h
+++ b/lib/dns/include/dns/rdataset.h
@@ -130,13 +130,6 @@ struct dns_rdataset {
 	 */
 	isc_stdtime_t resign;
 
-	/*
-	 * When a cache rdataset's TTL has expired but it hasn't been
-	 * cleaned up yet, it will have this value set so that the time
-	 * it expired can be printed by dns_master_dump*().
-	 */
-	isc_stdtime_t expired;
-
 	/*@{*/
 	/*%
 	 * These are for use by the rdataset implementation, and MUST NOT
diff --git a/lib/dns/masterdump.c b/lib/dns/masterdump.c
index 74ec7972ba..c66eb7cceb 100644
--- a/lib/dns/masterdump.c
+++ b/lib/dns/masterdump.c
@@ -1109,12 +1109,12 @@ again:
 			isc_result_t result;
 			if (STALE(rds)) {
 				fprintf(f, "; stale\n");
-			} else if (ANCIENT(rds) && rds->expired != 0) {
+			} else if (ANCIENT(rds)) {
 				isc_buffer_t b;
 				char buf[sizeof("YYYYMMDDHHMMSS")];
 				memset(buf, 0, sizeof(buf));
 				isc_buffer_init(&b, buf, sizeof(buf) - 1);
-				dns_time64_totext((uint64_t)rds->expired, &b);
+				dns_time64_totext((uint64_t)rds->ttl, &b);
 				fprintf(f,
 					"; expired since %s "
 					"(awaiting cleanup)\n",
diff --git a/lib/dns/rbtdb.c b/lib/dns/rbtdb.c
index f1074d3fd4..4d37a36ba3 100644
--- a/lib/dns/rbtdb.c
+++ b/lib/dns/rbtdb.c
@@ -3135,7 +3135,6 @@ bind_rdataset(dns_rbtdb_t *rbtdb, dns_rbtnode_t *node, rdatasetheader_t *header,
 	rdataset->type = RBTDB_RDATATYPE_BASE(header->type);
 	rdataset->covers = RBTDB_RDATATYPE_EXT(header->type);
 	rdataset->ttl = header->rdh_ttl - now;
-	rdataset->expired = 0;
 	rdataset->trust = header->trust;
 
 	if (NEGATIVE(header)) {
@@ -3164,8 +3163,7 @@ bind_rdataset(dns_rbtdb_t *rbtdb, dns_rbtnode_t *node, rdatasetheader_t *header,
 		rdataset->attributes |= DNS_RDATASETATTR_STALE;
 	} else if (IS_CACHE(rbtdb) && !ACTIVE(header, now)) {
 		rdataset->attributes |= DNS_RDATASETATTR_ANCIENT;
-		rdataset->expired = header->rdh_ttl;
-		rdataset->ttl = 0;
+		rdataset->ttl = header->rdh_ttl;
 	}
 
 	rdataset->private1 = rbtdb;