add question attribute

lib/dns/include/dns/rdataset.h

@@ -60,7 +60,7 @@
 ISC_LANG_BEGINDECLS
 
 typedef struct dns_rdatasetmethods {
-	dns_result_t		(*disassociate)(dns_rdataset_t *rdataset);
+	void			(*disassociate)(dns_rdataset_t *rdataset);
 	dns_result_t		(*first)(dns_rdataset_t *rdataset);
 	dns_result_t		(*next)(dns_rdataset_t *rdataset);
 	void			(*current)(dns_rdataset_t *rdataset,
@@ -106,7 +106,8 @@ struct dns_rdataset {
 	void *				private5;
 };
 
-#define DNS_RDATASETATTR_RENDERED	0x0001		/* used by message.c */
+#define DNS_RDATASETATTR_QUESTION	0x0001
+#define DNS_RDATASETATTR_RENDERED	0x0002		/* used by message.c */
 
 void
 dns_rdataset_init(dns_rdataset_t *rdataset);
@@ -147,7 +148,23 @@ dns_rdataset_disassociate(dns_rdataset_t *rdataset);
  *
  * Ensures:
  *	'rdataset' is a valid, disassociated rdataset.
- *	
+ */
+
+void
+dns_rdataset_makequestion(dns_rdataset_t *rdataset, dns_rdataclass_t rdclass,
+			  dns_rdatatype_t type);
+/*
+ * Make 'rdataset' a valid, associated, question rdataset, with a
+ * question class of 'rdclass' and type 'type'.
+ *
+ * Notes:
+ *	Question rdatasets have a class and type, but no rdata.
+ *
+ * Requires:
+ *	'rdataset' is a valid, disassociated rdataset.
+ *
+ * Ensures:
+ *	'rdataset' is a valid, associated, question rdataset.
  */
 
 dns_result_t
@@ -222,7 +239,6 @@ dns_result_t
 dns_rdataset_towire(dns_rdataset_t *rdataset,
 		    dns_name_t *owner_name,
 		    dns_compress_t *cctx,
-		    isc_boolean_t no_rdata_or_ttl,
 		    isc_buffer_t *target,
 		    unsigned int *countp);
 /*
@@ -232,10 +248,6 @@ dns_rdataset_towire(dns_rdataset_t *rdataset,
  * Notes:
  *	The rdata cursor position will be changed.
  *
- *	The no_rdata_or_ttl should normally be ISC_FALSE.  If it is ISC_TRUE
- *	the ttl and rdata fields are not printed.  This is mainly for use
- *	in the question section.
- *
  *	The number of RRs added to target will be added to *countp.
  *
  * Requires:

lib/dns/rdataset.c

@@ -101,6 +101,53 @@ dns_rdataset_disassociate(dns_rdataset_t *rdataset) {
 	rdataset->private5 = NULL;
 }
 
+static void
+question_disassociate(dns_rdataset_t *rdataset) {
+	(void)rdataset;
+}
+
+static dns_result_t
+question_cursor(dns_rdataset_t *rdataset) {
+	(void)rdataset;
+	return (DNS_R_NOMORE);
+}
+
+static void
+question_current(dns_rdataset_t *rdataset, dns_rdata_t *rdata) {
+	/*
+	 * This routine should never be called.
+	 */
+	(void)rdataset;
+	(void)rdata;
+	REQUIRE(0);
+}
+
+static dns_rdatasetmethods_t question_methods = {
+	question_disassociate,
+	question_cursor,
+	question_cursor,
+	question_current
+};
+
+void
+dns_rdataset_makequestion(dns_rdataset_t *rdataset, dns_rdataclass_t rdclass,
+			  dns_rdatatype_t type)
+{
+
+	/*
+	 * Make 'rdataset' a valid, associated, question rdataset, with a
+	 * question class of 'rdclass' and type 'type'.
+	 */
+
+	REQUIRE(DNS_RDATASET_VALID(rdataset));
+	REQUIRE(rdataset->methods == NULL);
+
+	rdataset->methods = &question_methods;
+	rdataset->rdclass = rdclass;
+	rdataset->type = type;
+	rdataset->attributes |= DNS_RDATASETATTR_QUESTION;
+}
+
 dns_result_t
 dns_rdataset_first(dns_rdataset_t *rdataset) {
 
@@ -144,7 +191,6 @@ dns_result_t
 dns_rdataset_towire(dns_rdataset_t *rdataset,
 		    dns_name_t *owner_name,
 		    dns_compress_t *cctx,
-		    isc_boolean_t no_rdata_or_ttl,
 		    isc_buffer_t *target,
 		    unsigned int *countp)
 {
@@ -155,6 +201,7 @@ dns_rdataset_towire(dns_rdataset_t *rdataset,
 	isc_buffer_t st;
 	isc_buffer_t rdlen;
 	unsigned int headlen;
+	isc_boolean_t question = ISC_FALSE;
 
 	/*
 	 * Convert 'rdataset' to wire format, compressing names as specified
@@ -162,14 +209,16 @@ dns_rdataset_towire(dns_rdataset_t *rdataset,
 	 */
 
 	REQUIRE(DNS_RDATASET_VALID(rdataset));
-	result = dns_rdataset_first(rdataset);
-	if (no_rdata_or_ttl) {
-		REQUIRE(result == DNS_R_NOMORE);
-	} else {
-		REQUIRE(result == DNS_R_SUCCESS);
-	}
 	REQUIRE(countp != NULL);
 
+	if ((rdataset->attributes & DNS_RDATASETATTR_QUESTION) != 0)
+		question = ISC_TRUE;
+	else {
+		result = dns_rdataset_first(rdataset);
+		if (result != DNS_R_SUCCESS)
+			return (result);
+	}
+
 	count = 0;
 	do {
 		/*
@@ -188,7 +237,7 @@ dns_rdataset_towire(dns_rdataset_t *rdataset,
 			return (result);
 		}
 		headlen = sizeof(dns_rdataclass_t) + sizeof(dns_rdatatype_t);
-		if (!no_rdata_or_ttl)
+		if (!question)
 			headlen += sizeof(dns_ttl_t)
 				+ 2;  /* XXX 2 for rdata len */
 		isc_buffer_available(target, &r);
@@ -200,7 +249,7 @@ dns_rdataset_towire(dns_rdataset_t *rdataset,
 		}
 		isc_buffer_putuint16(target, rdataset->type);
 		isc_buffer_putuint16(target, rdataset->rdclass);
-		if (!no_rdata_or_ttl) {
+		if (!question) {
 			isc_buffer_putuint32(target, rdataset->ttl);
 
 			/*