remove 'target' parameter from dns_name_concatenate()

the target buffer passed to dns_name_concatenate() was never
used (except for one place in dig, where it wasn't actually
needed, and has already been removed in a prior commit).
we can safely remove the parameter.

bin/dig/dighost.c

@@ -2277,7 +2277,7 @@ setup_lookup(dig_lookup_t *lookup) {
 				if (!dns_name_isabsolute(name)) {
 					result = dns_name_concatenate(
 						name, lookup->oname,
-						lookup->name, NULL);
+						lookup->name);
 				} else {
 					dns_name_copy(name, lookup->name);
 				}

bin/dnssec/dnssec-signzone.c

@@ -959,7 +959,7 @@ addnowildcardhash(hashlist_t *l,
 
 	wild = dns_fixedname_initname(&fixed);
 
-	result = dns_name_concatenate(dns_wildcardname, name, wild, NULL);
+	result = dns_name_concatenate(dns_wildcardname, name, wild);
 	if (result == ISC_R_NOSPACE) {
 		return;
 	}

lib/dns/adb.c

@@ -875,8 +875,7 @@ set_target(dns_adb_t *adb, const dns_name_t *name, const dns_name_t *fname,
 		prefix = dns_fixedname_initname(&fixed1);
 		new_target = dns_fixedname_initname(&fixed2);
 		dns_name_split(name, nlabels, prefix, NULL);
-		result = dns_name_concatenate(prefix, &dname.dname, new_target,
-					      NULL);
+		result = dns_name_concatenate(prefix, &dname.dname, new_target);
 		dns_rdata_freestruct(&dname);
 		if (result != ISC_R_SUCCESS) {
 			return result;

lib/dns/client.c

@@ -652,7 +652,7 @@ client_resfind(resctx_t *rctx, dns_fetchresponse_t *resp) {
 			prefix = dns_fixedname_initname(&fixed);
 			dns_name_split(name, nlabels, prefix, NULL);
 			tresult = dns_name_concatenate(prefix, &dname.dname,
-						       name, NULL);
+						       name);
 			dns_rdata_freestruct(&dname);
 			if (tresult == ISC_R_SUCCESS) {
 				want_restart = true;

lib/dns/dnssec.c

@@ -592,7 +592,7 @@ cleanup_struct:
 			RUNTIME_CHECK(dns_name_concatenate(
 					      dns_wildcardname,
 					      dns_fixedname_name(&fnewname),
-					      wild, NULL) == ISC_R_SUCCESS);
+					      wild) == ISC_R_SUCCESS);
 		}
 		inc_stat(dns_dnssecstats_wildcard);
 		ret = DNS_R_FROMWILDCARD;

lib/dns/include/dns/name.h

@@ -302,9 +302,10 @@ dns_name_setbuffer(dns_name_t *name, isc_buffer_t *buffer) {
  * Dedicate a buffer for use with 'name'.
  *
  * Notes:
- * \li	Specification of a target buffer in dns_name_fromwire(),
- *	dns_name_fromtext(), and dns_name_concatenate() is optional if
- *	'name' has a dedicated buffer.
+ * \li	Specification of a target buffer in dns_name_fromwire() and
+ *	dns_name_fromtext() is optional if 'name' has a dedicated buffer.
+ *	The target name in dns_name_concatenate() must have a dedicated
+ *	buffer.
  *
  * \li	The caller must not write to buffer until the name has been
  *	invalidated or is otherwise known not to be in use.
@@ -959,9 +960,11 @@ dns_name_downcase(const dns_name_t *source, dns_name_t *name);
 
 isc_result_t
 dns_name_concatenate(const dns_name_t *prefix, const dns_name_t *suffix,
-		     dns_name_t *name, isc_buffer_t *target);
+		     dns_name_t *name);
 /*%<
- *	Concatenate 'prefix' and 'suffix'.
+ *	Concatenate 'prefix' and 'suffix' and place the result in 'name'.
+ *	(Note that 'name' may be the same as 'prefix', in which case
+ *	'suffix' will be appended to it.)
  *
  * Requires:
  *
@@ -969,20 +972,10 @@ dns_name_concatenate(const dns_name_t *prefix, const dns_name_t *suffix,
  *
  *\li	'suffix' is a valid name or NULL.
  *
- *\li	'name' is a valid name or NULL.
- *
- *\li	'target' is a valid buffer or 'target' is NULL and 'name' has
- *	a dedicated buffer.
+ *\li	'name' is a valid name with a dedicated buffer.
  *
  *\li	If 'prefix' is absolute, 'suffix' must be NULL or the empty name.
  *
- * Ensures:
- *
- *\li	On success,
- *	 	If 'target' is not NULL and 'name' is not NULL, then 'name'
- *		is attached to it.
- *		The used space in target is updated.
- *
  * Returns:
  *\li	#ISC_R_SUCCESS
  *\li	#ISC_R_NOSPACE

lib/dns/name.c

@@ -1511,13 +1511,14 @@ dns_name_towire(const dns_name_t *name, dns_compress_t *cctx,
 
 isc_result_t
 dns_name_concatenate(const dns_name_t *prefix, const dns_name_t *suffix,
-		     dns_name_t *name, isc_buffer_t *target) {
-	unsigned char *ndata;
+		     dns_name_t *name) {
+	unsigned char *ndata = NULL;
 	unsigned int nrem, prefix_length, length;
 	bool copy_prefix = true;
 	bool copy_suffix = true;
 	bool absolute = false;
 	dns_name_t tmp_name;
+	isc_buffer_t *target = NULL;
 
 	/*
 	 * Concatenate 'prefix' and 'suffix'.
@@ -1525,10 +1526,9 @@ dns_name_concatenate(const dns_name_t *prefix, const dns_name_t *suffix,
 
 	REQUIRE(prefix == NULL || DNS_NAME_VALID(prefix));
 	REQUIRE(suffix == NULL || DNS_NAME_VALID(suffix));
-	REQUIRE(name == NULL || DNS_NAME_VALID(name));
-	REQUIRE((target != NULL && ISC_BUFFER_VALID(target)) ||
-		(target == NULL && name != NULL &&
-		 ISC_BUFFER_VALID(name->buffer)));
+	REQUIRE(DNS_NAME_VALID(name) && ISC_BUFFER_VALID(name->buffer));
+	REQUIRE(DNS_NAME_BINDABLE(name));
+
 	if (prefix == NULL || prefix->length == 0) {
 		copy_prefix = false;
 	}
@@ -1543,13 +1543,9 @@ dns_name_concatenate(const dns_name_t *prefix, const dns_name_t *suffix,
 		dns_name_init(&tmp_name);
 		name = &tmp_name;
 	}
-	if (target == NULL) {
-		INSIST(name->buffer != NULL);
-		target = name->buffer;
-		isc_buffer_clear(name->buffer);
-	}
 
-	REQUIRE(DNS_NAME_BINDABLE(name));
+	target = name->buffer;
+	isc_buffer_clear(target);
 
 	/*
 	 * Set up.
@@ -1583,8 +1579,7 @@ dns_name_concatenate(const dns_name_t *prefix, const dns_name_t *suffix,
 	}
 
 	/*
-	 * If 'prefix' and 'name' are the same object, and the object has
-	 * a dedicated buffer, and we're using it, then we don't have to
+	 * If 'prefix' and 'name' are the same object, we don't have to
 	 * copy anything.
 	 */
 	if (copy_prefix && (prefix != name || prefix->buffer != target)) {

lib/dns/nsec.c

@@ -483,8 +483,7 @@ dns_nsec_noexistnodata(dns_rdatatype_t type, const dns_name_t *name,
 			dns_name_getlabelsequence(&nsec.next, labels - nlabels,
 						  nlabels, &common);
 		}
-		result = dns_name_concatenate(dns_wildcardname, &common, wild,
-					      NULL);
+		result = dns_name_concatenate(dns_wildcardname, &common, wild);
 		if (result != ISC_R_SUCCESS) {
 			dns_rdata_freestruct(&nsec);
 			(*logit)(arg, ISC_LOG_DEBUG(3),

lib/dns/qpzone.c

@@ -2960,7 +2960,7 @@ find_wildcard(qpz_search_t *search, qpznode_t **nodep,
 			 * Construct the wildcard name for this level.
 			 */
 			result = dns_name_concatenate(dns_wildcardname,
-						      &node->name, wname, NULL);
+						      &node->name, wname);
 			if (result != ISC_R_SUCCESS) {
 				break;
 			}

lib/dns/rdata/generic/mx_15.c

@@ -290,7 +290,7 @@ additionaldata_mx(ARGS_ADDLDATA) {
 
 	dns_fixedname_init(&fixed);
 	result = dns_name_concatenate(&port25, &name,
-				      dns_fixedname_name(&fixed), NULL);
+				      dns_fixedname_name(&fixed));
 	if (result != ISC_R_SUCCESS) {
 		return ISC_R_SUCCESS;
 	}

lib/dns/rdata/in_1/srv_33.c

@@ -341,7 +341,7 @@ additionaldata_in_srv(ARGS_ADDLDATA) {
 	}
 
 	result = dns_name_concatenate(dns_fixedname_name(&fixed), &name,
-				      dns_fixedname_name(&fixed), NULL);
+				      dns_fixedname_name(&fixed));
 	if (result != ISC_R_SUCCESS) {
 		return ISC_R_SUCCESS;
 	}

lib/dns/resolver.c

@@ -6929,8 +6929,7 @@ is_answertarget_allowed(fetchctx_t *fctx, dns_name_t *qname, dns_name_t *rname,
 		tname = dns_fixedname_initname(&fixed);
 		nlabels = dns_name_countlabels(rname);
 		dns_name_split(qname, nlabels, &prefix, NULL);
-		result = dns_name_concatenate(&prefix, &dname.dname, tname,
-					      NULL);
+		result = dns_name_concatenate(&prefix, &dname.dname, tname);
 		if (result == DNS_R_NAMETOOLONG) {
 			SET_IF_NOT_NULL(chainingp, true);
 			return true;

lib/dns/rpz.c

@@ -1071,7 +1071,7 @@ name2data(dns_rpz_zone_t *rpz, dns_rpz_type_t rpz_type,
 		n -= dns_name_countlabels(&rpz->nsdname);
 	}
 	dns_name_getlabelsequence(src_name, prefix_len, n, &tmp_name);
-	(void)dns_name_concatenate(&tmp_name, dns_rootname, trig_name, NULL);
+	(void)dns_name_concatenate(&tmp_name, dns_rootname, trig_name);
 }
 
 #ifndef HAVE_BUILTIN_CLZ

lib/dns/rrl.c

@@ -432,7 +432,7 @@ make_key(const dns_rrl_t *rrl, dns_rrl_key_t *key,
 			 */
 			wild = dns_fixedname_initname(&fixed);
 			result = dns_name_concatenate(dns_wildcardname, origin,
-						      wild, NULL);
+						      wild);
 			if (result != ISC_R_SUCCESS) {
 				/*
 				 * Fallback to use the zone's origin name

lib/dns/sdlz.c

@@ -549,8 +549,8 @@ getnodedata(dns_db_t *db, const dns_name_t *name, bool create,
 				fname = dns_fixedname_name(&fixed);
 				dns_name_getlabelsequence(
 					name, i + 1, dlabels - i - 1, fname);
-				result = dns_name_concatenate(
-					dns_wildcardname, fname, fname, NULL);
+				result = dns_name_concatenate(dns_wildcardname,
+							      fname, fname);
 				if (result != ISC_R_SUCCESS) {
 					MAYBE_UNLOCK(sdlz->dlzimp);
 					return result;

lib/dns/ssu.c

@@ -631,7 +631,7 @@ dns_ssutable_checkrules(dns_ssutable_t *table, const dns_name_t *signer,
 		case dns_ssumatchtype_selfwild:
 			wildcard = dns_fixedname_initname(&fixed);
 			result = dns_name_concatenate(dns_wildcardname, signer,
-						      wildcard, NULL);
+						      wildcard);
 			if (result != ISC_R_SUCCESS) {
 				if (logit) {
 					isc_log_write(

lib/dns/tkey.c

@@ -475,8 +475,7 @@ dns_tkey_processquery(dns_message_t *msg, dns_tkeyctx_t *tctx,
 			RETERR(isc_hex_totext(&r, 2, "", &b));
 			RETERR(dns_name_fromtext(keyname, &b, NULL, 0, NULL));
 		}
-		RETERR(dns_name_concatenate(keyname, dns_rootname, keyname,
-					    NULL));
+		RETERR(dns_name_concatenate(keyname, dns_rootname, keyname));
 
 		result = dns_tsigkey_find(&tsigkey, keyname, NULL, ring);
 		if (result == ISC_R_SUCCESS) {

lib/dns/validator.c

@@ -2610,8 +2610,7 @@ findnsec3proofs(dns_validator_t *val) {
 	{
 		val->attributes |= VALATTR_FOUNDCLOSEST;
 		result = dns_name_concatenate(dns_wildcardname, closest,
-					      dns_fixedname_name(&val->wild),
-					      NULL);
+					      dns_fixedname_name(&val->wild));
 		RUNTIME_CHECK(result == ISC_R_SUCCESS);
 	} else {
 		val->attributes &= ~VALATTR_FOUNDNOQNAME;

lib/dns/zone.c

@@ -4881,7 +4881,7 @@ check_reportchannel(dns_zone_t *zone, dns_db_t *db) {
 	 * Otherwise, we need a '*._er' wildcard with a TXT rdataset.
 	 */
 	name = dns_fixedname_initname(&fixed);
-	CHECK(dns_name_concatenate(&er, &zone->origin, name, NULL));
+	CHECK(dns_name_concatenate(&er, &zone->origin, name));
 	CHECK(dns_db_findnode(db, name, false, &node));
 
 	dns_db_currentversion(db, &version);

lib/ns/query.c

@@ -3181,7 +3181,7 @@ rpz_get_p_name(ns_client_t *client, dns_name_t *p_name, dns_rpz_zone_t *rpz,
 	for (;;) {
 		dns_name_getlabelsequence(trig_name, first, labels - first - 1,
 					  &prefix);
-		result = dns_name_concatenate(&prefix, suffix, p_name, NULL);
+		result = dns_name_concatenate(&prefix, suffix, p_name);
 		if (result == ISC_R_SUCCESS) {
 			break;
 		}
@@ -4900,9 +4900,8 @@ redirect2(ns_client_t *client, dns_name_t *name, dns_rdataset_t *rdataset,
 		dns_name_init(&prefix);
 		dns_name_getlabelsequence(client->query.qname, 0, labels - 1,
 					  &prefix);
-		result = dns_name_concatenate(&prefix,
-					      client->view->redirectzone,
-					      redirectname, NULL);
+		result = dns_name_concatenate(
+			&prefix, client->view->redirectzone, redirectname);
 		if (result != ISC_R_SUCCESS) {
 			return ISC_R_NOTFOUND;
 		}
@@ -4980,7 +4979,7 @@ redirect2(ns_client_t *client, dns_name_t *name, dns_rdataset_t *rdataset,
 	/*
 	 * Make the name absolute.
 	 */
-	result = dns_name_concatenate(found, dns_rootname, found, NULL);
+	result = dns_name_concatenate(found, dns_rootname, found);
 	RUNTIME_CHECK(result == ISC_R_SUCCESS);
 
 	dns_name_copy(found, name);
@@ -7269,7 +7268,7 @@ query_rpzcname(query_ctx_t *qctx, dns_name_t *cname) {
 			       dns_fixedname_name(&suffix));
 		result = dns_name_concatenate(dns_fixedname_name(&prefix),
 					      dns_fixedname_name(&suffix),
-					      qctx->fname, NULL);
+					      qctx->fname);
 		if (result == DNS_R_NAMETOOLONG) {
 			client->message->rcode = dns_rcode_yxdomain;
 		} else if (result != ISC_R_SUCCESS) {
@@ -9271,8 +9270,8 @@ query_addnxrrsetnsec(query_ctx_t *qctx) {
 
 	dns_name_split(qctx->fname, sig.labels + 1, NULL, fname);
 	/* This will succeed, since we've stripped labels. */
-	RUNTIME_CHECK(dns_name_concatenate(dns_wildcardname, fname, fname,
-					   NULL) == ISC_R_SUCCESS);
+	RUNTIME_CHECK(dns_name_concatenate(dns_wildcardname, fname, fname) ==
+		      ISC_R_SUCCESS);
 	query_addrrset(qctx, &fname, &qctx->rdataset, &qctx->sigrdataset, dbuf,
 		       DNS_SECTION_AUTHORITY);
 }
@@ -10385,7 +10384,7 @@ query_dname(query_ctx_t *qctx) {
 	INSIST(qctx->fname == NULL);
 	qctx->dbuf = ns_client_getnamebuf(qctx->client);
 	qctx->fname = ns_client_newname(qctx->client, qctx->dbuf, &b);
-	result = dns_name_concatenate(prefix, tname, qctx->fname, NULL);
+	result = dns_name_concatenate(prefix, tname, qctx->fname);
 	dns_message_puttempname(qctx->client->message, &tname);
 
 	/*
@@ -11190,8 +11189,7 @@ again:
 		/*
 		 * Add the no wildcard proof.
 		 */
-		result = dns_name_concatenate(dns_wildcardname, cname, wname,
-					      NULL);
+		result = dns_name_concatenate(dns_wildcardname, cname, wname);
 		if (result != ISC_R_SUCCESS) {
 			goto cleanup;
 		}
@@ -11232,7 +11230,7 @@ again:
 				dns_name_split(name, nlabels, NULL, wname);
 			}
 			result = dns_name_concatenate(dns_wildcardname, wname,
-						      wname, NULL);
+						      wname);
 			if (result == ISC_R_SUCCESS) {
 				have_wname = true;
 			}