listincoming: add htlc_min_msat, public and peer_features fields.

This is needed for offers to generate blinded paths.

No documentation changes since listincoming is an undocumented
internal hack interface which topology presents for production
of routehints.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

common/gossmap.c

@@ -1289,3 +1289,22 @@ int gossmap_node_get_feature(const struct gossmap *map,
 	return map_feature_test(map, COMPULSORY_FEATURE(fbit),
 				n->nann_off + feature_len_off + 2, feature_len);
 }
+
+u8 *gossmap_node_get_features(const tal_t *ctx,
+			      const struct gossmap *map,
+			      const struct gossmap_node *n)
+{
+	u8 *ret;
+	/* Note that first two bytes are message type */
+	const size_t feature_len_off = 2 + 64;
+	size_t feature_len;
+
+	if (n->nann_off == 0)
+		return NULL;
+
+	feature_len = map_be16(map, n->nann_off + feature_len_off);
+	ret = tal_arr(ctx, u8, feature_len);
+
+	map_copy(map, n->nann_off + feature_len_off + 2, ret, feature_len);
+	return ret;
+}

common/gossmap.h

@@ -134,21 +134,26 @@ u8 *gossmap_node_get_announce(const tal_t *ctx,
 			      const struct gossmap *map,
 			      const struct gossmap_node *n);
 
-/* Return the feature bit (odd or even), or -1 if neither. */
+/* Return the channel feature bit (odd or even), or -1 if neither. */
 int gossmap_chan_get_feature(const struct gossmap *map,
 			     const struct gossmap_chan *c,
 			     int fbit);
 
-/* Return the feature bitmap */
+/* Return the channel feature bitmap */
 u8 *gossmap_chan_get_features(const tal_t *ctx,
 			      const struct gossmap *map,
 			      const struct gossmap_chan *c);
 
-/* Return the feature bit (odd or even), or -1 if neither (or no announcement) */
+/* Return the node feature bit (odd or even), or -1 if neither (or no announcement) */
 int gossmap_node_get_feature(const struct gossmap *map,
 			     const struct gossmap_node *n,
 			     int fbit);
 
+/* Return the node feature bitmap: NULL if no announcement. */
+u8 *gossmap_node_get_features(const tal_t *ctx,
+			      const struct gossmap *map,
+			      const struct gossmap_node *n);
+
 /* Returns details from channel_update (must be gossmap_chan_set, and
  * does not work for local_updatechan! */
 void gossmap_chan_get_update_details(const struct gossmap *map,

plugins/topology.c

@@ -577,6 +577,7 @@ static struct command_result *json_listincoming(struct command *cmd,
 		struct gossmap_chan *ourchan;
 		struct gossmap_node *peer;
 		struct short_channel_id scid;
+		const u8 *peer_features;
 
 		ourchan = gossmap_nth_chan(gossmap, me, i, &dir);
 		/* If its half is disabled, ignore. */
@@ -593,6 +594,9 @@ static struct command_result *json_listincoming(struct command *cmd,
 		json_add_amount_msat_only(js, "fee_base_msat",
 					  amount_msat(ourchan->half[!dir]
 						      .base_fee));
+		json_add_amount_msat_only(js, "htlc_min_msat",
+					  amount_msat(fp16_to_u64(ourchan->half[!dir]
+								  .htlc_min)));
 		json_add_amount_msat_only(js, "htlc_max_msat",
 					  amount_msat(fp16_to_u64(ourchan->half[!dir]
 								  .htlc_max)));
@@ -602,6 +606,10 @@ static struct command_result *json_listincoming(struct command *cmd,
 		json_add_amount_msat_only(js, "incoming_capacity_msat",
 					 peer_capacity(gossmap,
 						       me, peer, ourchan));
+		json_add_bool(js, "public", !ourchan->private);
+		peer_features = gossmap_node_get_features(tmpctx, gossmap, peer);
+		if (peer_features)
+			json_add_hex_talarr(js, "peer_features", peer_features);
 		json_object_end(js);
 	}
 done: