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#include "utils.h"
#include <arpa/inet.h>
#include <netinet/ip.h>
#include <stdlib.h>
#include <errno.h>
#include <stdio.h>
#include <string.h>
int get_socket() {
int sockfd = socket(AF_INET, SOCK_DGRAM, 0);
if (sockfd < 0) {
fprintf(stderr, "Socket error: %s\n", strerror(errno));
exit(EXIT_FAILURE);
}
return sockfd;
}
void bind_to_port(int sockfd, uint16_t port) {
struct sockaddr_in server_address;
bzero(&server_address, sizeof(server_address));
server_address.sin_family = AF_INET;
server_address.sin_port = htons(port);
server_address.sin_addr.s_addr = htonl(INADDR_ANY);
if (bind(sockfd, (struct sockaddr*)&server_address, sizeof(server_address)) < 0) {
fprintf(stderr, "Bind error: %s\n", strerror(errno));
exit(EXIT_FAILURE);
}
int broadcastPermission = 1;
setsockopt (sockfd, SOL_SOCKET, SO_BROADCAST, (void *)&broadcastPermission, sizeof(broadcastPermission));
}
long get_time_interval(struct timespec start, struct timespec finish) {
return S_TO_MS(finish.tv_sec - start.tv_sec) + NS_TO_MS(finish.tv_nsec - start.tv_nsec);
}
int poll_socket_modify_timeout(int sockfd, int *timeout) {
if (*timeout < 0) {
fprintf(stderr, "poll_modify_timeout: timeout is negative.\n");
exit(EXIT_FAILURE);
}
struct pollfd fds;
fds.fd = sockfd;
fds.events = POLLIN;
fds.revents = 0;
struct timespec start;
clock_gettime(CLOCK_REALTIME, &start);
int result = poll(&fds, 1, *timeout);
if (result == -1) {
fprintf(stderr, "poll error: %s\n", strerror(errno));
exit(EXIT_FAILURE);
}
if (result == 0) {
*timeout = 0;
return 0;
}
struct timespec finish;
clock_gettime(CLOCK_REALTIME, &finish);
*timeout -= get_time_interval(start, finish);
printf("Timeout: %dms, time waiting: %ldms.\n", *timeout, get_time_interval(start, finish));
return result;
}
/* For debug purposes only */
void recv_and_print(int sockfd, int networks_number, struct router_addr *networks) {
struct sockaddr_in sender;
socklen_t sender_len = sizeof(sender);
uint8_t buffer[IP_MAXPACKET + 1];
ssize_t datagram_len = recvfrom(sockfd, buffer, IP_MAXPACKET, 0,
(struct sockaddr*)&sender, &sender_len);
if (datagram_len < 0) {
fprintf(stderr, "recvfrom error: %s\n", strerror(errno));
exit(EXIT_FAILURE);
}
for (int i = 0; i < networks_number; i++) {
if (networks[i].addr.s_addr == sender.sin_addr.s_addr) {
return;
}
}
char sender_ip_str[20];
inet_ntop(AF_INET, &(sender.sin_addr), sender_ip_str, sizeof(sender_ip_str));
printf("Received UDP packet from IP address: %s, port %d\n",
sender_ip_str, ntohs(sender.sin_port));
buffer[datagram_len] = 0;
printf("%ld-byte message: +%s+\n", datagram_len, buffer);
}
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