lua: fix a mistake in kr_query, and simplify serve_stale

Fields after kr_nsrep got offset; fortunately only new fields were
added in there, unused from lua so far.

config.mk

@@ -3,7 +3,7 @@ MAJOR := 2
 MINOR := 0
 PATCH := 0
 EXTRA :=
-ABIVER := 5
+ABIVER := 6
 BUILDMODE := dynamic
 HARDENING := yes
 

daemon/lua/kres-gen.lua

@@ -201,7 +201,7 @@ struct kr_nsrep {
 	unsigned int reputation;
 	const knot_dname_t *name;
 	struct kr_context *ctx;
-	/* beware: hidden stub */
+	/* beware: hidden stub, to avoid hardcoding sockaddr lengths */
 };
 struct kr_query {
 	struct kr_query *parent;
@@ -218,12 +218,12 @@ struct kr_query {
 	uint64_t timestamp_mono;
 	struct timeval timestamp;
 	struct kr_zonecut zone_cut;
-	struct kr_nsrep ns;
 	struct kr_layer_pickle *deferred;
 	uint32_t uid;
 	struct kr_query *cname_parent;
 	struct kr_request *request;
 	kr_stale_cb stale_cb;
+	struct kr_nsrep ns;
 };
 struct kr_context {
 	struct kr_qflags options;
@@ -286,7 +286,6 @@ struct sockaddr *kr_straddr_socket(const char *, int);
 int kr_ranked_rrarray_add(ranked_rr_array_t *, const knot_rrset_t *, uint8_t, _Bool, uint32_t, knot_mm_t *);
 void kr_qflags_set(struct kr_qflags *, struct kr_qflags);
 void kr_qflags_clear(struct kr_qflags *, struct kr_qflags);
-void kr_query_set_stale_cb(struct kr_query *, kr_stale_cb);
 int kr_zonecut_add(struct kr_zonecut *, const knot_dname_t *, const knot_rdata_t *);
 void kr_zonecut_set(struct kr_zonecut *, const knot_dname_t *);
 uint64_t kr_now();

daemon/lua/kres-gen.sh

@@ -80,7 +80,7 @@ genResType "struct knot_rrset" | sed 's/\<owner\>/_owner/'
 ## Some definitions would need too many deps, so shorten them.
 
 genResType "struct kr_nsrep" | sed '/union/,$ d'
-printf "\t/* beware: hidden stub */\n};\n"
+printf "\t/* beware: hidden stub, to avoid hardcoding sockaddr lengths */\n};\n"
 
 genResType "struct kr_query"
 
@@ -153,7 +153,6 @@ EOF
 	kr_ranked_rrarray_add
 	kr_qflags_set
 	kr_qflags_clear
-	kr_query_set_stale_cb
 	kr_zonecut_add
 	kr_zonecut_set
 	kr_now

lib/rplan.c

@@ -27,11 +27,6 @@
 #define QUERY_PROVIDES(q, name, cls, type) \
     ((q)->sclass == (cls) && (q)->stype == type && knot_dname_is_equal((q)->sname, name))
 
-void kr_query_set_stale_cb(struct kr_query *qry, kr_stale_cb cb)
-{
-	qry->stale_cb = cb;
-}
-
 inline static unsigned char chars_or(const unsigned char a, const unsigned char b)
 {
 	return a | b;

lib/rplan.h

@@ -78,10 +78,6 @@ void kr_qflags_clear(struct kr_qflags *fl1, struct kr_qflags fl2);
  */
 typedef int32_t (*kr_stale_cb)(int32_t ttl, const knot_dname_t *owner, uint16_t type,
 				const struct kr_query *qry);
-/** Trivial wrapper to set kr_query::stale_cb.
- * For some unknown reason, direct setting via lua doesn't work. */
-KR_EXPORT
-void kr_query_set_stale_cb(struct kr_query *qry, kr_stale_cb cb);
 
 /**
  * Single query representation.
@@ -103,13 +99,14 @@ struct kr_query {
 	                           * query to upstream resolver (milliseconds). */
 	struct timeval timestamp; /**< Real time for TTL+DNSSEC checks (.tv_sec only). */
 	struct kr_zonecut zone_cut;
-	struct kr_nsrep ns;
 	struct kr_layer_pickle *deferred;
 	uint32_t uid; /**< Query iteration number, unique within the kr_rplan. */
 	/** Pointer to the query that originated this one because of following a CNAME (or NULL). */
 	struct kr_query *cname_parent;
 	struct kr_request *request; /**< Parent resolution request. */
 	kr_stale_cb stale_cb; /**< See the type */
+	/* Beware: this must remain the last, because of lua bindings. */
+	struct kr_nsrep ns;
 };
 
 /** @cond internal Array of queries. */

modules/serve_stale/serve_stale.lua

@@ -28,7 +28,7 @@ M.layer = {
 		local deadline = qry.creation_time_mono + M.timeout
 		if now > deadline then
 			--log('[     ][stal]   => deadline has passed')
-			ffi.C.kr_query_set_stale_cb(qry, M.callback)
+			qry.stale_cb = M.callback
 			-- TODO: probably start the same request that doesn't stale-serve,
 			-- but first we need some detection of non-interactive / internal requests.
 			-- resolve(kres.dname2str(qry.sname), qry.stype, qry.sclass)