lightningd/lightningd.h: Maintain a round-robin list of channels.

lightningd/channel.c

@@ -110,6 +110,8 @@ static void destroy_channel(struct channel *channel)
 	channel_set_owner(channel, NULL);
 
 	list_del_from(&channel->peer->channels, &channel->list);
+
+	list_del(&channel->rr_list);
 }
 
 void delete_channel(struct channel *channel STEALS)
@@ -275,6 +277,7 @@ struct channel *new_channel(struct peer *peer, u64 dbid,
 	channel->forgets = tal_arr(channel, struct command *, 0);
 
 	list_add_tail(&peer->channels, &channel->list);
+	list_add_tail(&peer->ld->rr_channels, &channel->rr_list);
 	tal_add_destructor(channel, destroy_channel);
 
 	/* Make sure we see any spends using this key */

lightningd/channel.h

@@ -136,6 +136,9 @@ struct channel {
 
 	/* Any commands trying to forget us. */
 	struct command **forgets;
+
+	/* Our position in the round-robin list.  */
+	struct list_node rr_list;
 };
 
 struct channel *new_channel(struct peer *peer, u64 dbid,

lightningd/lightningd.c

@@ -285,6 +285,11 @@ static struct lightningd *new_lightningd(const tal_t *ctx)
 	 */
 	ld->exit_code = NULL;
 
+	/*~ We maintain a round-robin list of channels.
+	 * This round-robin list of channels is used to ensure that
+	 * each invoice we generate has a different set of channels.  */
+	list_head_init(&ld->rr_channels);
+
 	return ld;
 }
 

lightningd/lightningd.h

@@ -274,6 +274,9 @@ struct lightningd {
 
 	/* If non-NULL, contains the exit code to use.  */
 	int *exit_code;
+
+	/* The round-robin list of channels, for use when doing MPP.  */
+	struct list_head rr_channels;
 };
 
 /* Turning this on allows a tal allocation to return NULL, rather than aborting.