gossip: Add the `struct exclude_entry` and `enum exclude_entry_type`

gossipd/routing.h

@@ -268,6 +268,19 @@ struct route_hop {
 	u32 delay;
 };
 
+enum exclude_entry_type {
+	EXCLUDE_CHANNEL = 1,
+	EXCLUDE_NODE = 2
+};
+
+struct exclude_entry {
+	enum exclude_entry_type type;
+	union {
+		struct short_channel_id_dir chan_id;
+		struct node_id node_id;
+	} u;
+};
+
 struct routing_state *new_routing_state(const tal_t *ctx,
 					const struct chainparams *chainparams,
 					const struct node_id *local_id,

lightningd/gossip_msg.c

@@ -195,3 +195,33 @@ void towire_peer_features(u8 **pptr, const struct peer_features *pf)
 	towire_u16(pptr, tal_count(pf->globalfeatures));
 	towire_u8_array(pptr, pf->globalfeatures, tal_count(pf->globalfeatures));
 }
+
+struct exclude_entry *fromwire_exclude_entry(const tal_t *ctx,
+					     const u8 **pptr, size_t *max)
+{
+	struct exclude_entry *entry = tal(ctx, struct exclude_entry);
+	entry->type = fromwire_u8(pptr, max);
+	switch (entry->type) {
+		case EXCLUDE_CHANNEL:
+			fromwire_short_channel_id_dir(pptr, max, &entry->u.chan_id);
+			return entry;
+		case EXCLUDE_NODE:
+			fromwire_node_id(pptr, max, &entry->u.node_id);
+			return entry;
+		default:
+			fromwire_fail(pptr, max);
+			return NULL;
+	}
+}
+
+void towire_exclude_entry(u8 **pptr, const struct exclude_entry *entry)
+{
+	assert(entry->type == EXCLUDE_CHANNEL ||
+	       entry->type == EXCLUDE_NODE);
+
+	towire_u8(pptr, entry->type);
+	if (entry->type == EXCLUDE_CHANNEL)
+		towire_short_channel_id_dir(pptr, &entry->u.chan_id);
+	else
+		towire_node_id(pptr, &entry->u.node_id);
+}

lightningd/gossip_msg.h

@@ -61,4 +61,9 @@ fromwire_gossip_getchannels_entry(const tal_t *ctx,
 void towire_gossip_getchannels_entry(
     u8 **pptr, const struct gossip_getchannels_entry *entry);
 
+struct exclude_entry *
+fromwire_exclude_entry(const tal_t *ctx,
+		       const u8 **pptr, size_t *max);
+void towire_exclude_entry(u8 **pptr, const struct exclude_entry *entry);
+
 #endif /* LIGHTNING_LIGHTNINGD_GOSSIP_MSG_H */

tools/generate-wire.py

@@ -217,6 +217,7 @@ class Type(FieldSet):
         'wirestring',
         'per_peer_state',
         'bitcoin_tx_output',
+        'exclude_entry',
     ]
 
     # Some BOLT types are re-typed based on their field name