dazibao/src/node.h

// Define constants

#ifndef NODE_H
#define NODE_H

#include <stdlib.h>
#include <time.h>
#include <stdio.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <string.h>

#include "tlv.h"
#include "hash.h"
#include "parser.h"

// On which port do we listen to
#define LISTEN_PORT 1212

// The node ID
#define NODE_ID 42675882021843277

// The number of neighbours
// The neighbour table has 15 entries
#define NEIGHBOUR_MAX 15

/* la table de voisins, qui est indexée par adresses de socket (des paires (IP, Port)),
 * et dont chaque entrée contient un booléen indiquant si le pair est permanent
 * (configuré au lancement) ou transitoire, et la date de dernière réception d’un
 * paquet de la part de ce pair ;
*/
typedef struct neighbour_peer {
    struct in6_addr ip;
    short port;
    char is_temporary;
    struct timeval last_seen;
} neighbour_peer;

// The strucuture to hold the messages
/* It's a list of triplets, (Li,Si,Di)
 * Li : The Node ID of the publisher 64 bits
 * Si : the sequence number 16 bits
 * Di : the data of the message 192 bytes
*/

typedef struct pub_data {
	unsigned char length;
    long id;
    short seqno;
    char *data;
} pub_data;

// General list
typedef struct list {
	void *data;
	void *next;
} list;

// Static variables
static list *data_list;
static list *neighbour_list;

// TODO

// fonctions signatures
void listen_for_packets();

int check_header(char * received_datagram[], int buffer_len, struct packet * packet_to_return);

int validate_tlvs(struct packet * pack, struct tlv_list * tlv_l);

int update_neighbours();

int work_with_tlvs(char * data[], short packet_len, struct sockaddr_in6 sender);

void add_tlv(struct packet *packet, union tlv *tlv, char type);

// int send_packet();

/* Takes a TLV and sends it over to everyone in the list of addresses.
 * Returns -1 in case of error, 0 otherwise.
 */
int send_tlv(union tlv * tlv_to_send, int tlv_size, struct sockaddr_in6 * dest_list[], int dest_list_size, int socket_num);

/* Takes a list of TLV and sends them over to everyone in the list of addresses.
 * Returns -1 in case of error, 0 otherwise.
 */
int send_tlvs(struct list * tlv_list, int tlv_size, struct sockaddr_in6 * dest_list[], int dest_list_size, int socket_num);

// threaded functions
void t_ask_for_more_peers();

void t_update_neighbours();

void t_get_network_state();

// Helper functions
int len_list(list *l);

neighbour_peer *get_random_neighbour();

// get data associated with id, if it doesn't exist return NULL
pub_data *get_data(long id);

// Take data as args and create a pub_data structure in the heap
pub_data *copy_data(unsigned char len, long id, short seqno, char *data);

// add new data to data list
void add_data(unsigned char len, long id, short seqno, char *data);

#endif