#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>

#ifdef WIN32
    #include <winsock.h>
    #include "winerr.h"

    #define    close    closesocket
    #define sleep   Sleep
    #define ONESEC  1000
#else
    #include <unistd.h>
    #include <sys/socket.h>
    #include <sys/types.h>
    #include <arpa/inet.h>
    #include <netdb.h>

    #define ONESEC  1
#endif



#define VER     "0.1"
#define BUFFSZ  4096
#define MS      "master.quake3arena.com"
#define MSPORT  27950
#define REQ     "\xff\xff\xff\xff" \
                "getservers 68\n"
#define TIMEOUT 5



int timeout(int sock);
u_int resolv(char *host);
void std_err(void);



int main(int argc, char *argv[]) {
    struct    sockaddr_in     peer;
    int        sd,
            err,
            rlen,
            i,
            tot = 0;
    u_char  *buff,
            *ptr;
    u_int  ip;
    u_short port;

#ifdef WIN32
    WSADATA    wsadata;
    WSAStartup(MAKEWORD(2,0), &wsadata);
#endif
    FILE *file;
    file = fopen("input.txt","w");
    setbuf(stdout, NULL);

    peer.sin_addr.s_addr = resolv(MS);
    peer.sin_port        = htons(MSPORT);
    peer.sin_family      = AF_INET;
    rlen                 = sizeof(peer);

    buff = malloc(BUFFSZ + 1);
    if(!buff) std_err();

    sd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
    if(sd < 0) std_err();

    err = sendto(sd, REQ, sizeof(REQ) - 1, 0, (struct sockaddr *)&peer, rlen);
    if(err < 0) std_err();

    while(1) {
        err = timeout(sd);
        if(err < 0) break;
        err = recvfrom(sd, buff, BUFFSZ, 0, (struct sockaddr *)&peer, &rlen);
        if(err < 0) std_err();
        if(!err) break;

        if(memcmp(buff + 4, "getserversResponse", 18)) break;

        i = 23;             /* 4 (ffffffff) + 18 (get..) + 1 (\) */
        ptr = buff + 23;
        while(i < err) {
            if(!memcmp(ptr, "EOT", 3)) break;
            ip = *(u_int *)ptr;
            port = *(u_short *)(ptr + 4);
            printf("%15s   %hu\n",
                inet_ntoa(*(struct in_addr *)&ip),
                htons(port));
            ptr += 7;
            i += 7;
            tot++;
            fprintf(file,"%15s   %hu\n",
                inet_ntoa(*(struct in_addr *)&ip),
                htons(port));
        }
    }
    fclose(file); /*done!*/ 
    close(sd);

    printf("\nTotal servers found: %d\n\n", tot);

    return(0);
}



int timeout(int sock) {
    struct    timeval    tout;
    fd_set    fd_read;
    int    err;

    tout.tv_sec = TIMEOUT;
    tout.tv_usec = 0;
    FD_ZERO(&fd_read);
    FD_SET(sock, &fd_read);
    err = select(sock + 1, &fd_read, NULL, NULL, &tout);
    if(err < 0) std_err();
    if(!err) return(-1);
    return(0);
}



u_int resolv(char *host) {
    struct        hostent    *hp;
    u_int        host_ip;

    host_ip = inet_addr(host);
    if(host_ip == INADDR_NONE) {
        hp = gethostbyname(host);
        if(!hp) {
            printf("\nError: Unable to resolv hostname (%s)\n", host);
            exit(1);
        } else host_ip = *(u_int *)(hp->h_addr);
    }
    return(host_ip);
}



#ifndef WIN32
    void std_err(void) {
        perror("\nError");
        exit(1);
    }
#endif

 while(1) {
        err = timeout(sd);
        if(err < 0) break;
        err = recvfrom(sd, buff, BUFFSZ, 0, (struct sockaddr *)&peer, &rlen);
        if(err < 0) std_err();
        if(!err) break;

        if(memcmp(buff + 4, "getserversResponse", 18)) break;

        i = 23;             /* 4 (ffffffff) + 18 (get..) + 1 (\) */
        ptr = buff + 23;
        while(i < err) {
            if(!memcmp(ptr, "EOT", 3)) break;
            ip = *(u_int *)ptr;
            port = *(u_short *)(ptr + 4);
            printf("%15s   %hu\n",
                inet_ntoa(*(struct in_addr *)&ip),
                htons(port));
            ptr += 7;
            i += 7;
            tot++;
            fprintf(file,"%15s   %hu\n",
                inet_ntoa(*(struct in_addr *)&ip),
                htons(port));
        }
    }