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/*
* Program: router
* Autor: Franciszek Malinka, 316093
*/
#include "network_addr.h"
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
struct in_addr _get_broadcast_address(struct in_addr addr, uint16_t netmask) {
struct in_addr result = addr;
result.s_addr = ntohl(result.s_addr);
/* bitshift by more than 31 is UB */
if (netmask == 0) {
result.s_addr = -1;
}
else {
result.s_addr |= ((1 << (32 - netmask)) - 1);
}
result.s_addr = htonl(result.s_addr);
return result;
}
struct in_addr _get_network_address(struct in_addr addr, uint16_t netmask) {
struct in_addr result = addr;
result.s_addr = ntohl(result.s_addr);
if (netmask == 0) {
result.s_addr = 0;
}
else {
result.s_addr &= ~((1 << (32 - netmask)) - 1);
}
result.s_addr = htonl(result.s_addr);
return result;
}
struct in_addr get_broadcast_address(struct network_addr na) {
return _get_broadcast_address(na.addr, na.netmask);
}
struct in_addr get_network_address(struct network_addr na) {
return _get_network_address(na.addr, na.netmask);
}
void pretty_print_network(struct network_addr na) {
char ip_addr[20];
inet_ntop(AF_INET, &na.addr, ip_addr, sizeof(ip_addr));
printf("%s/%d\n", ip_addr, na.netmask);
}
struct network_addr stona(char *str) {
struct network_addr result;
char addr[20];
size_t ip_preffix = strcspn(str, "/");
strncpy(addr, str, ip_preffix);
addr[ip_preffix] = 0;
inet_pton(AF_INET, addr, &(result.addr));
result.netmask = atoi(str + ip_preffix + 1);
return result;
}
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