/*
 * udpclient.c - A simple UDP client
 * usage: udpclient <host> <port>
 */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>
#include <arpa/inet.h>
#include <sys/ioctl.h>
#include <net/if.h>
#include <errno.h>

#define BUFSIZE 1024

/*
 * error - wrapper for perror
 */
void error(char *msg)
{
    perror(msg);
    exit(0);
}

int main(int argc, char **argv)
{
    int sockfd, portno, n;
    int serverlen;
    struct sockaddr_in serveraddr;
    struct sockaddr_in bindaddr;

    char *bindaddr_str;

    struct hostent *server;
    char *hostname;


    char buf[BUFSIZE];

    /* check command line arguments */
    if (argc != 4) {
        fprintf(stderr,"usage: %s <hostname> <port> <bind iface>\n", argv[0]);
        exit(0);
    }
    hostname = argv[1];
    portno = atoi(argv[2]);
    bindaddr_str = argv[3];

    /* socket: create the socket */
    sockfd = socket(AF_INET, SOCK_DGRAM, 0);
    if (sockfd < 0)
        error("ERROR opening socket");


    struct ifreq ifr;

    snprintf(ifr.ifr_name, sizeof(ifr.ifr_name), bindaddr_str);

/*  if (setsockopt(sockfd, SOL_SOCKET, SO_BINDTODEVICE, (void *)&ifr, sizeof(ifr)) < 0) {
        fprintf(stderr, "ERROR: can't bind to device %s,\n%s",
            bindaddr_str, strerror(errno));
        exit(1);
    }*/


    /* gethostbyname: get the server's DNS entry */
    server = gethostbyname(hostname);
    if (server == NULL) {
        fprintf(stderr,"ERROR, no such host as %s\n", hostname);
        exit(0);
    }

    /* build the server's Internet address */
    bzero((char *) &serveraddr, sizeof(serveraddr));
    serveraddr.sin_family = AF_INET;
    bcopy((char *)server->h_addr,
            (char *)&serveraddr.sin_addr.s_addr, server->h_length);
    serveraddr.sin_port = htons(portno);

    /*memset((void *) &bindaddr, 0, sizeof(bindaddr));
    bindaddr.sin_family = AF_INET;
    inet_pton(AF_INET, bindaddr_str, &(bindaddr.sin_addr));

    if (bind(sockfd, (struct sockaddr *) &bindaddr, sizeof(bindaddr)) < 0) {
        perror("Error in binding");
        exit(1);
    }*/



    while (1) {
        /* get a message from the user */
        bzero(buf, BUFSIZE);
        printf("Please enter msg: ");
        fgets(buf, BUFSIZE, stdin);
        /* send the message to the server */
        serverlen = sizeof(serveraddr);
        n = sendto(sockfd, buf, strlen(buf), 0,
               (struct sockaddr *)&serveraddr, serverlen);
        printf("sent %s", buf);
        if (n < 0)
            error("ERROR in sendto");

        /* print the server's reply */
        n = recvfrom(sockfd, buf, strlen(buf), 0,
                 (struct sockaddr *)&serveraddr, &serverlen);
        if (n < 0)
            error("ERROR in recvfrom");
        printf("Echo from server: %s", buf);
    }
    return 0;
}