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

#define DATA "exit"

int main(int argc, char *argv[])
{
    int sock;
    socklen_t length;
    struct sockaddr_in server;
    int msgsock;
    char buf[1024];
    int rval;
    sock = socket(AF_INET, SOCK_STREAM, 0);
    if (sock == -1)
    {
        perror("opening stream socket");
        exit(1);
    }
    server.sin_family = AF_INET;
    server.sin_addr.s_addr = htoml(INADDR_ANY);
    if(argc == 2){
        server.sin_port = htons(atoi(argv[1]));
    }
    else{
        server.sin_port = 0;
    }
    if(bind(sock, (struct sockaddr *) &server, sizeof server) == -1){
        perror("binding stream socket");
        exit(1);
    }
    length = sizeof server;
    if(getsockname(sock,(struct sockaddr *) &server, &length) == -1){
        perror("getting socket name");
        exit(1);
    }
    printf("socket port %d\n", ntohs(server.sin_port));
    listen(sock, 5);
    do{
        if ((msgsock = accept(sock, (struct sockaddr *)NULL, (socklen_t *)NULL)) == -1)
        {
            perror("accept");
        }
        else
            do
            {
                memset(buf, 0, sizeof buf);
                if ((rval = read(msgsock, buf, 1024)) == -1)
                    perror("reading stream message");
                dprintf(1, "-[%d]\n", rval);
                if (rval == 0)
                {
                    printf("connecting finished\n");
                }
                else
                {
                    dprintf(1, "[%s]\n", buf);
                }
            } while ((rval > 0) && (strcmp(buf, FIN)));
        close(msgsock);

    }while(strcmp(buf,FIN));
    exit(0);
}