GAME TIC-TAC-TOE

// UDP Library // Computer Engineering IoT/Networks Course // Jason Losh //----------------------------------------------------------------------------- // Device includes, defines, and assembler directives //----------------------------------------------------------------------------- #include <stdlib.h> // EXIT_ codes #include <stdbool.h> // bool #include <stdio.h> // printf, scanf #include <string.h> // memset, strlen, strcmp #include <unistd.h> // close #include <sys/socket.h> // socket, bind, recvfrom, sendto, setsockopt #include <netinet/in.h> // in_addr #include <arpa/inet.h> // inet_aton, inet_ntoa #include "udp.h" //----------------------------------------------------------------------------- // Local statics //----------------------------------------------------------------------------- int listen_sockfd; struct in_addr listen_remote_ip; //----------------------------------------------------------------------------- // Functions //----------------------------------------------------------------------------- // Sends UDP package containing a string to ipv4Address::port // returns true if successful bool sendData(const char ipv4Address[], int port, const char str[]) { struct sockaddr_in remote_addr; struct in_addr remote_ip; int sockfd; int count; int result; bool ok; ok = (sockfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP)) != -1; if (ok) { inet_aton(ipv4Address, &remote_ip); remote_addr.sin_family = AF_INET; remote_addr.sin_port = htons(port); remote_addr.sin_addr = remote_ip; memset(&(remote_addr.sin_zero), 0, 8); count = sendto(sockfd, str, strlen(str)+1, 0, (struct sockaddr *)&remote_addr, sizeof(struct sockaddr)); ok = count > 0; close(sockfd); } return ok; } // Opens listener port that accepts only data from given address bool openListenerPort(const char ipv4Address[], int listenPort) { struct sockaddr_in local_addr; int opt = 1; int result; bool ok = true; // Store expected source of messages inet_aton(ipv4Address, &listen_remote_ip); local_addr.sin_family = AF_INET; local_addr.sin_port = htons(listenPort); local_addr.sin_addr.s_addr = INADDR_ANY; memset(&(local_addr.sin_zero), 0, 8); ok = (listen_sockfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP)) != -1; if (ok) ok = setsockopt(listen_sockfd, SOL_SOCKET, SO_REUSEADDR | SO_REUSEPORT, &opt, sizeof(opt)) != -1; if (ok) ok = bind(listen_sockfd, (struct sockaddr *)&local_addr, sizeof(struct sockaddr)) != -1; return ok; } void receiveData(char str[], int str_length) { // Listener struct sockaddr_in sender_addr; int sender_add_length = sizeof(struct sockaddr); int count; bool received = false; while (!received) { count = recvfrom(listen_sockfd, str, str_length, 0, (struct sockaddr *)&sender_addr, &sender_add_length); if (count > 0) received = strcmp(inet_ntoa(sender_addr.sin_addr), inet_ntoa(listen_remote_ip)) == 0; } } // Closes listener port void closeListenerPort() { close(listen_sockfd); }