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/*
* Program: router
* Autor: Franciszek Malinka, 316093
*/
#include "dist_vector.h"
#include <stdio.h>
#include <time.h>
#include <string.h>
bool is_connected_directly(struct vector_item item) {
return item.is_connected_directly;
}
bool is_reachable(struct vector_item item) {
return (item.distance < INFINITY_DIST);
}
void init_dv(list_t *dv, int n_cnt, struct network_addr *neighbours) {
for (int i = 0; i < n_cnt; i++) {
struct vector_item new_item;
new_item.network = neighbours[i];
new_item.distance = INFINITY_DIST;
new_item.is_connected_directly = true;
insert(dv, &new_item, sizeof(new_item));
}
}
void update_dv_reachability(list_t *distance_vector) {
reset(distance_vector);
while (distance_vector->it != NULL) {
struct vector_item *current = (struct vector_item *)distance_vector->it->data;
if(++current->reachable > REACHABILITY_WAIT_TIME) {
if (current->distance >= INFINITY_DIST) {
if (!is_connected_directly(*current)) {
erase_it(distance_vector);
}
} else {
current->distance = INFINITY_DIST;
current->reachable = 0;
}
}
iterate(distance_vector);
}
}
void update_dv_new_item(list_t *distance_vector, struct vector_item new_item) {
bool new_entry = true;
reset(distance_vector);
while (distance_vector->it != NULL) {
struct vector_item *current = (struct vector_item *)distance_vector->it->data;
/* If the network is already in the distance vector, then we possibly want to change it:
* - if the new item has better distance than the previous one, then we just want to change it no matter what,
* - if the new item has the same via ip, then we want to check two things:
* - if new item has infinity dist, then we want to set infinity (if it wasn't set, then we want to change reachable to 0)
* - if new item has < inf dist, then we want to change reachable to 0 and set our dist accordingly.
* - else we ignore the entry.
*/
if (get_network_address(current->network).s_addr == get_network_address(new_item.network).s_addr) {
if (current->distance > new_item.distance) {
*current = new_item;
current->reachable = 0;
} else if(current->via_ip.s_addr == new_item.via_ip.s_addr) {
if (new_item.distance >= INFINITY_DIST) {
if (current->distance < INFINITY_DIST) {
current->distance = INFINITY_DIST;
current->reachable = 0;
}
} else {
current->distance = new_item.distance;
current->reachable = 0;
}
}
new_entry = false;
}
iterate(distance_vector);
}
if (new_entry && new_item.reachable < INFINITY_DIST) {
insert(distance_vector, &new_item, sizeof(new_item));
}
}
void print_dv(list_t *distance_vector) {
time_t rawtime;
struct tm * timeinfo;
time ( &rawtime );
timeinfo = localtime ( &rawtime );
char t[100];
strcpy(t, asctime(timeinfo));
t[strlen(t) - 1] = 0;
printf("Distance vector [%s]:\n", t);
reset(distance_vector);
while (distance_vector->it != NULL) {
char addr[20], via_addr[20];
struct vector_item current = *(struct vector_item *)distance_vector->it->data;
struct in_addr net_addr = get_network_address(current.network);
inet_ntop(AF_INET, &net_addr, addr, sizeof(addr));
printf("%s/%d ", addr, current.network.netmask);
if (is_reachable(current)) printf("distance %d ", current.distance);
else printf("unreachable ");
inet_ntop(AF_INET, ¤t.via_ip, via_addr, sizeof(via_addr));
if (is_connected_directly(current)) printf("connected directly\n");
else printf("via %s\n", via_addr);
iterate(distance_vector);
}
printf("\n");
}
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