#define closesocket close
#include <sys/socket.h>
#include <arpa/inet.h>
#include <unistd.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <unistd.h>
#include <stdio.h>
#include <stdio.h>
#include <stdlib.h> // for atoi()
#include <string.h>
#define PROTOPORT 27015 // default protocol port number
#define QLEN 6 // size of request queue

void errorhandler(char *errorMessage) {
printf ("%s", errorMessage);
}

void clearwinsock() {

}

int main(int argc, char *argv[]) {
    int port;
    if (argc > 1) {
        port = atoi(argv[1]); // if argument specified convert argument tobinary
    }
    else
        port = PROTOPORT; // use default port number
    if (port < 0) {
        printf("bad port number %s \n", argv[1]);
        return 0;
    }


    // CREAZIONE DELLA SOCKET
    int my_socket;
    my_socket = socket(PF_INET, SOCK_STREAM, IPPROTO_TCP);
    if (my_socket < 0) {
    errorhandler("socket creation failed.\n");
    return -1;
    }
    // ASSEGNAZIONE DI UN INDIRIZZO ALLA SOCKET
    struct sockaddr_in sad;
    memset(&sad, 0, sizeof(sad)); // ensures that extra bytes contain 0
    sad.sin_family = AF_INET;
    sad.sin_addr.s_addr = inet_addr("127.0.0.1");
    sad.sin_port = htons(PROTOPORT); /* converts values between the host and
    network byte order. Specifically, htons() converts 16-bit quantities
    from host byte order to network byte order. */
    if (bind(my_socket, (struct sockaddr*) &sad, sizeof(sad)) < 0) {
        errorhandler("bind() failed.\n");
        close(my_socket);
        return -1;
    }


    // SETTAGGIO DELLA SOCKET ALL'ASCOLTO
    if (listen (my_socket, QLEN) < 0) {
        errorhandler("listen() failed.\n");
        close(my_socket);
        return -1;
    }
    printf("1");

    // ACCETTARE UNA NUOVA CONNESSIONE
    struct sockaddr_in cad; // structure for the client address
    int client_socket;

    // socket descriptor for the client
    int client_len;

    // the size of the client address
    printf("Waiting for a client to connect...");
    while (1) { /* oppure for (;;) */
        client_len = sizeof(cad); // set the size of the client address
        if ((client_socket = accept(my_socket, (struct sockaddr*)&cad, &client_len)) < 0) {
            errorhandler("accept() failed.\n");

            // CHIUSURA DELLA CONNESSIONE
            close(my_socket);
            return 0;
        }

        printf("Handling client %s\n", inet_ntoa(cad.sin_addr));
    } // end-while
}