Routing-Table-Manager/Routing-Table/routing-table.c

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "routing-table.h"
#include "dll.h"

/*
* Display each (entry) of a routing table.
*/

void display_routing_table(const dll_t* routing_table) {

	printf("Printing routing table.\n");

	dll_node_t* node = routing_table->head->next;
	while (node != routing_table->head) {
		routing_table_entry_t entry = *((routing_table_entry_t*)node->data);

		printf("Destination IP: %s  Mask: %u Gateway IP: %s  OIF: %s\n", entry.dest,
			entry.mask, entry.gw, entry.oif);
		node = node->next;
	}
}

/*
* Look up entry in routing table by destination IP and subnet mask.
*/

dll_node_t* find_routing_table_entry(const dll_t* routing_table, const char* dest,
	const unsigned short mask) {

	dll_node_t* node = routing_table->head->next;
	while (node != routing_table->head) {

		routing_table_entry_t entry = *((routing_table_entry_t*)node->data);
		if (!strcmp(entry.dest, dest) && entry.mask == mask) {
			break;
		}

		node = node->next;
	}

	return node;
}

/*
* Updates the entry whose destination IP is dest and subnet mask is mask.
*/

void update(dll_node_t* node, const char* gw, const char* oif) {

	routing_table_entry_t* entry = node->data;
	memset(entry->gw, 0, IP_ADDR_LEN);
	memset(entry->oif, 0, OIF_LEN);
	memcpy(entry->gw, gw, strlen(gw));
	memcpy(entry->oif, oif, strlen(oif));

}