node_id.h

/* Encapsulation for pubkeys used as node ids: more compact, more dangerous. */
#ifndef LIGHTNING_COMMON_NODE_ID_H
#define LIGHTNING_COMMON_NODE_ID_H
#include "config.h"
#include <bitcoin/pubkey.h>

struct node_id {
	u8 k[PUBKEY_CMPR_LEN];
};

static inline bool node_id_eq(const struct node_id *a,
			      const struct node_id *b)
{
	return memcmp(a->k, b->k, sizeof(a->k)) == 0;
}

/* Is this actually a valid pubkey?  Relatively expensive. */
bool node_id_valid(const struct node_id *id);

/* Convert from pubkey to compressed pubkey. */
void node_id_from_pubkey(struct node_id *id, const struct pubkey *key);

/* Returns false if not a valid pubkey: relatively expensive */
WARN_UNUSED_RESULT
bool pubkey_from_node_id(struct pubkey *key, const struct node_id *id);

/* Convert to hex string of SEC1 encoding. */
char *node_id_to_hexstr(const tal_t *ctx, const struct node_id *id);

/* Convert from hex string of SEC1 encoding: checks validity! */
bool node_id_from_hexstr(const char *str, size_t slen, struct node_id *id);

/* Compare the keys `a` and `b`. Return <0 if `a`<`b`, 0 if equal and >0 otherwise */
int node_id_cmp(const struct node_id *a, const struct node_id *b);

/* If the two nodes[] are id1 and id2, which index would id1 be? */
static inline int node_id_idx(const struct node_id *id1,
			      const struct node_id *id2)
{
	return node_id_cmp(id1, id2) > 0;
}

#endif /* LIGHTNING_COMMON_NODE_ID_H */