core-lightning/gossipd/broadcast.h
Rusty Russell 6afc7dcc09 gossipd: don't increment broadcast_index until *after* message sent.
If the peer is moved from remote to local, this may be lost; it's more
secure to increment after we've sent the broadcast.
2017-12-17 02:44:20 +00:00

41 lines
1.1 KiB
C

#ifndef LIGHTNING_LIGHTNINGD_GOSSIP_BROADCAST_H
#define LIGHTNING_LIGHTNINGD_GOSSIP_BROADCAST_H
#include "config.h"
#include <ccan/intmap/intmap.h>
#include <ccan/list/list.h>
#include <ccan/short_types/short_types.h>
#include <ccan/tal/tal.h>
/* Common functionality to implement staggered broadcasts with replacement. */
struct queued_message {
int type;
/* Unique tag specifying the msg origin */
void *tag;
/* Serialized payload */
u8 *payload;
};
struct broadcast_state {
u32 next_index;
UINTMAP(struct queued_message *) broadcasts;
};
struct broadcast_state *new_broadcast_state(tal_t *ctx);
/* Queue a new message to be broadcast and replace any outdated
* broadcast. Replacement is done by comparing the `type` and the
* `tag`, if both match the old message is dropped from the queue. The
* new message is added to the top of the broadcast queue. */
void queue_broadcast(struct broadcast_state *bstate,
const int type,
const u8 *tag,
const u8 *payload);
struct queued_message *next_broadcast_message(struct broadcast_state *bstate, u64 last_index);
#endif /* LIGHTNING_LIGHTNINGD_GOSSIP_BROADCAST_H */