Print in dump-file stale ttl

This change makes rndc dumpdb correctly print the "; stale" line.
It also provides extra information on how long this data may still
be served to clients (in other words how long the stale RRset may
still be used).

lib/dns/include/dns/rdataset.h

@@ -108,6 +108,7 @@ struct dns_rdataset {
 	unsigned int			magic;		/* XXX ? */
 	dns_rdatasetmethods_t *		methods;
 	ISC_LINK(dns_rdataset_t)	link;
+
 	/*
 	 * XXX do we need these, or should they be retrieved by methods?
 	 * Leaning towards the latter, since they are not frequently required
@@ -116,12 +117,19 @@ struct dns_rdataset {
 	dns_rdataclass_t		rdclass;
 	dns_rdatatype_t			type;
 	dns_ttl_t			ttl;
+	/*
+	 * Stale ttl is used to see how long this RRset can still be used
+	 * to serve to clients, after the TTL has expired.
+	 */
+	dns_ttl_t			stale_ttl;
 	dns_trust_t			trust;
 	dns_rdatatype_t			covers;
+
 	/*
 	 * attributes
 	 */
 	unsigned int			attributes;
+
 	/*%
 	 * the counter provides the starting point in the "cyclic" order.
 	 * The value UINT32_MAX has a special meaning of "picking up a
@@ -129,11 +137,13 @@ struct dns_rdataset {
 	 * increment the counter.
 	 */
 	uint32_t			count;
+
 	/*
 	 * This RRSIG RRset should be re-generated around this time.
 	 * Only valid if DNS_RDATASETATTR_RESIGN is set in attributes.
 	 */
 	isc_stdtime_t			resign;
+
 	/*@{*/
 	/*%
 	 * These are for use by the rdataset implementation, and MUST NOT

lib/dns/masterdump.c

@@ -81,6 +81,9 @@ struct dns_master_style {
  */
 #define DNS_TOTEXT_LINEBREAK_MAXLEN 100
 
+/*% Does the rdataset 'r' contain a stale answer? */
+#define STALE(r) (((r)->attributes & DNS_RDATASETATTR_STALE) != 0)
+
 /*%
  * Context structure for a masterfile dump in progress.
  */
@@ -1040,8 +1043,11 @@ dump_rdatasets_text(isc_mem_t *mctx, const dns_name_t *name,
 			/* Omit negative cache entries */
 		} else {
 			isc_result_t result;
-			if (rds->ttl < ctx->serve_stale_ttl)
-				fprintf(f, "; stale\n");
+			if (STALE(rds)) {
+				fprintf(f, "; stale (for %u more seconds)\n",
+					(rds->stale_ttl -
+					 ctx->serve_stale_ttl));
+			}
 			result = dump_rdataset(mctx, name, rds, ctx, buffer, f);
 			if (result != ISC_R_SUCCESS)
 				dumpresult = result;
@@ -1509,13 +1515,14 @@ dumpctx_create(isc_mem_t *mctx, dns_db_t *db, dns_dbversion_t *version,
 
 	dctx->do_date = dns_db_iscache(dctx->db);
 	if (dctx->do_date) {
-	    /*
-	     * Adjust the date backwards by the serve-stale TTL, if any.
-	     * This is so the TTL will be loaded correctly when next started.
-	     */
-	    (void)dns_db_getservestalettl(dctx->db,
-					  &dctx->tctx.serve_stale_ttl);
-	    dctx->now -= dctx->tctx.serve_stale_ttl;
+		/*
+		 * Adjust the date backwards by the serve-stale TTL, if any.
+		 * This is so the TTL will be loaded correctly when next
+		 * started.
+		 */
+		(void)dns_db_getservestalettl(dctx->db,
+					      &dctx->tctx.serve_stale_ttl);
+		dctx->now -= dctx->tctx.serve_stale_ttl;
 	}
 
 	if (dctx->format == dns_masterformat_text &&

lib/dns/rbtdb.c

@@ -2979,6 +2979,8 @@ bind_rdataset(dns_rbtdb_t *rbtdb, dns_rbtnode_t *node,
 		rdataset->attributes |= DNS_RDATASETATTR_PREFETCH;
 	if (STALE(header)) {
 		rdataset->attributes |= DNS_RDATASETATTR_STALE;
+		rdataset->stale_ttl =
+			(rbtdb->serve_stale_ttl + header->rdh_ttl) - now;
 		rdataset->ttl = 0;
 	}
 	rdataset->private1 = rbtdb;

lib/ns/query.c

@@ -149,7 +149,7 @@ do { \
 #define NOQNAME(r)		(((r)->attributes & \
 				  DNS_RDATASETATTR_NOQNAME) != 0)
 
-/*% Does the rdataset 'r' contains a stale answer? */
+/*% Does the rdataset 'r' contain a stale answer? */
 #define STALE(r)		(((r)->attributes & \
 				  DNS_RDATASETATTR_STALE) != 0)