RTM Project

Routing-Table/routing-table.c

@@ -0,0 +1,59 @@
+#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));
+
+}