#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <sys/time.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/ioctl.h>
#include <arpa/inet.h>
#include <netinet/in.h>
#include <netinet/ip.h>

struct _entry {
	u_int16_t gameid;
	u_int32_t ip;
	u_int16_t port1;
	u_int16_t port2;
} __attribute__ ((packed));

static char scanmsg[] = "\xFF\xFF\xFF\xFFHLSWLANSEARCH";

char *gameid2name[] = { "Unknown",	//  0
			"HL",
			"Q1",
			"Q2",
			"Q3Comp",
			"UT",
			"Q3",
			"EF",
			"RtCW",
			"GSProt",
			"CCR",		// 10
			"MoHAA",
			"JK2",
			"SoF2",
			"UT2K3",
			"AAO",
			"BF1942",
			"AvP2",
			"Rune",
			"IGI2",
			"NWN",		// 20
			"MoHAAS",
			"OPF",
			"OPFR",
			"DVS",
			"ET",
			"EF2",
			"JK3",
			"MoHAAB",
			"Tribes2",
			"HALO",		// 30
			"CoD",
			"Savage",
			"UT2K4",
			"HLSteam",
			"BFV",
			"GS2Prot",
			"PK",
			"D3",
			"OGPProt",
			"HL2",		// 40
			"TribesV",
			"CoDUO" };

int main(int argc, char *argv[]) {
	struct sockaddr_in dst;
	struct timeval tv;
	struct _entry *srv;
	fd_set fdsel, fdcpy;
	int sock, i = 1, recvsize;
	void *pkt;

	if ((sock = socket(PF_INET, SOCK_DGRAM, 0)) < 0) {
		perror("socket()");
		exit(-1);
	}

	if (setsockopt(sock, SOL_SOCKET, SO_BROADCAST, &i, sizeof(i))) {
		perror("setsockopt()");
		exit(-1);
	}
	
	dst.sin_family = AF_INET;
	dst.sin_port = htons(7130);
	inet_aton("0.0.0.0", &dst.sin_addr);
	
	if (bind(sock, (struct sockaddr *)&dst, sizeof(dst)) < 0) {
		perror("bind()");
		exit(-1);
	}
	
	dst.sin_port = htons(7140);
	inet_aton("255.255.255.255", &dst.sin_addr);
	
	if (sendto(sock, scanmsg, sizeof(scanmsg), 0, (struct sockaddr *)&dst, sizeof(dst)) < 0) {
		perror("sendto()");
		exit(-1);
	}

	FD_ZERO(&fdsel);
	FD_SET(sock, &fdsel);

	tv.tv_sec = 1;
	tv.tv_usec = 0;
	
	while (1) {
		memcpy(&fdcpy, &fdsel, sizeof(fdsel));
		if (select(FD_SETSIZE, &fdcpy, NULL, NULL, &tv) < 0) {
			perror("select");
			exit(-1);
		}

		if (tv.tv_sec == 0 && tv.tv_usec == 0)
			exit(0);
		
		ioctl(sock, FIONREAD, &recvsize);

		if (recvsize <= 0) {
			continue;
		}
		
		if (!(pkt = malloc(recvsize))) {
			perror("malloc()");
			exit(-1);
		}

		i = sizeof(struct sockaddr_in);
		recvsize = recvfrom(sock, pkt, recvsize, 0, (struct sockaddr *)&dst, &i);

		printf("received packet from: %s:%d  size=%d\n",
			inet_ntoa(dst.sin_addr), ntohs(dst.sin_port), recvsize);

		srv = pkt + sizeof(scanmsg);
		while ((void *)srv < pkt + recvsize) {
			dst.sin_addr.s_addr = srv->ip;
			printf("  ip=%s port1=%d port2=%d gameid=%d (%s)\n",
				inet_ntoa(dst.sin_addr),
				srv->port1,
				srv->port2,
				srv->gameid,
				gameid2name[srv->gameid]);
			srv++;
		}
		free(pkt);
	}

	return 0;
}