/* Server program for Internet UDP sockets */
/* From the book of Haviland, pp. 269 - 270, modified */
/* Read more explanation in this book */
/* Server starts, creates and binds a socket */
/* and, before reading from client, sleeps */
/* for 60 seconds */
/* During this period, the client starts, sends */
/* a request to the server and terminates */
/* After awaiking, the server reads */
/* the client's request and terminates */


#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <string.h>
#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <netdb.h>
#include <arpa/inet.h>
#include <ctype.h>

#define PORT  7000 /* Port of this server */
#define SIZE sizeof(struct sockaddr_in)

int
main(void)
{
    char buf[1024];
    int n, s, ns, len;
    struct sockaddr_in srv = {AF_INET, PORT, INADDR_ANY};
    struct sockaddr_in cli; /* For client's address */
    int cli_len = SIZE;
     
    printf("SERVER: starting ...\n");
    
    /*
     * Create the Internet socket, of SOCK_DGRAM type.
     */
    if ((s = socket(AF_INET, SOCK_DGRAM, 0)) < 0) 
        {
        perror("socket problem");
        exit(1);
        }


    /*
     * For simplicity, use the IP address as the OS selects.
     * It is more preferable to set a specific IP address
     * which must be known to all clients...
     */


    /*
     * Bind the socket to the the IP address of this host.
     */
    if (bind(s, (struct sockaddr *) &srv, SIZE) < 0) 
        {
        perror("bind problem");
        exit(1);
        }
     printf ("... and sleeping during 60 sec\n");   
     /* Long sleep before reading */
     sleep(60); /* 60 sec */

    /*
     * Now read from the socket s
     */
    n = recvfrom(s, buf, sizeof(buf), 0, (struct sockaddr *)&cli, &cli_len);
    if (n < 0) {perror("recvfrom problem"); exit(1);}

    write(1, buf, n);
    printf ("SERVER: terminated...\n");
    /*
     * Close the socket and terminate.
     */

    close(s);
    exit(0);
}