Files @ r5149:d4d2b8888034
Branch filter:

Location: cpp/openttd-patchpack/source/network_udp.c

KUDr
(svn r7241) -Fix: czech town name generator now uses proper diacritics (Hadez)
  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
/* $Id$ */

#ifdef ENABLE_NETWORK

#include "stdafx.h"
#include "debug.h"
#include "string.h"
#include "network_data.h"
#include "date.h"
#include "map.h"
#include "network_gamelist.h"
#include "network_udp.h"
#include "variables.h"

//
// This file handles all the LAN-stuff
// Stuff like:
//   - UDP search over the network
//

typedef enum {
	PACKET_UDP_CLIENT_FIND_SERVER,
	PACKET_UDP_SERVER_RESPONSE,
	PACKET_UDP_CLIENT_DETAIL_INFO,
	PACKET_UDP_SERVER_DETAIL_INFO,   // Is not used in OpenTTD itself, only for external querying
	PACKET_UDP_SERVER_REGISTER,      // Packet to register itself to the master server
	PACKET_UDP_MASTER_ACK_REGISTER,  // Packet indicating registration has succedeed
	PACKET_UDP_CLIENT_GET_LIST,      // Request for serverlist from master server
	PACKET_UDP_MASTER_RESPONSE_LIST, // Response from master server with server ip's + port's
	PACKET_UDP_SERVER_UNREGISTER,    // Request to be removed from the server-list
	PACKET_UDP_END
} PacketUDPType;

enum {
	ADVERTISE_NORMAL_INTERVAL = 30000, // interval between advertising in ticks (15 minutes)
	ADVERTISE_RETRY_INTERVAL  =   300, // readvertise when no response after this many ticks (9 seconds)
	ADVERTISE_RETRY_TIMES     =     3  // give up readvertising after this much failed retries
};

#define DEF_UDP_RECEIVE_COMMAND(type) void NetworkPacketReceive_ ## type ## _command(Packet *p, struct sockaddr_in *client_addr)
static void NetworkSendUDP_Packet(SOCKET udp, Packet* p, struct sockaddr_in* recv);

static NetworkClientState _udp_cs;

DEF_UDP_RECEIVE_COMMAND(PACKET_UDP_CLIENT_FIND_SERVER)
{
	Packet *packet;
	// Just a fail-safe.. should never happen
	if (!_network_udp_server)
		return;

	packet = NetworkSend_Init(PACKET_UDP_SERVER_RESPONSE);

	// Update some game_info
	_network_game_info.game_date = _date;
	_network_game_info.map_width = MapSizeX();
	_network_game_info.map_height = MapSizeY();
	_network_game_info.map_set = _opt.landscape;

	NetworkSend_uint8 (packet, NETWORK_GAME_INFO_VERSION);

	/* NETWORK_GAME_INFO_VERSION = 3 */
	NetworkSend_uint32(packet, _network_game_info.game_date);
	NetworkSend_uint32(packet, _network_game_info.start_date);

	/* NETWORK_GAME_INFO_VERSION = 2 */
	NetworkSend_uint8 (packet, _network_game_info.companies_max);
	NetworkSend_uint8 (packet, ActivePlayerCount());
	NetworkSend_uint8 (packet, _network_game_info.spectators_max);

	/* NETWORK_GAME_INFO_VERSION = 1 */
	NetworkSend_string(packet, _network_game_info.server_name);
	NetworkSend_string(packet, _network_game_info.server_revision);
	NetworkSend_uint8 (packet, _network_game_info.server_lang);
	NetworkSend_uint8 (packet, _network_game_info.use_password);
	NetworkSend_uint8 (packet, _network_game_info.clients_max);
	NetworkSend_uint8 (packet, _network_game_info.clients_on);
	NetworkSend_uint8 (packet, NetworkSpectatorCount());
	NetworkSend_string(packet, _network_game_info.map_name);
	NetworkSend_uint16(packet, _network_game_info.map_width);
	NetworkSend_uint16(packet, _network_game_info.map_height);
	NetworkSend_uint8 (packet, _network_game_info.map_set);
	NetworkSend_uint8 (packet, _network_game_info.dedicated);

	// Let the client know that we are here
	NetworkSendUDP_Packet(_udp_server_socket, packet, client_addr);

	free(packet);

	DEBUG(net, 2)("[NET][UDP] Queried from %s", inet_ntoa(client_addr->sin_addr));
}

DEF_UDP_RECEIVE_COMMAND(PACKET_UDP_SERVER_RESPONSE)
{
	extern const char _openttd_revision[];
	NetworkGameList *item;
	byte game_info_version;

	// Just a fail-safe.. should never happen
	if (_network_udp_server)
		return;

	game_info_version = NetworkRecv_uint8(&_udp_cs, p);

	if (_udp_cs.has_quit) return;

	DEBUG(net, 6)("[NET][UDP] Server response from %s:%d", inet_ntoa(client_addr->sin_addr),ntohs(client_addr->sin_port));

	// Find next item
	item = NetworkGameListAddItem(inet_addr(inet_ntoa(client_addr->sin_addr)), ntohs(client_addr->sin_port));

	/* Please observer the order. In the order in which packets are sent
	 * they are to be received */
	switch (game_info_version) {
		case 3:
			item->info.game_date     = NetworkRecv_uint32(&_udp_cs, p);
			item->info.start_date    = NetworkRecv_uint32(&_udp_cs, p);
			/* Fallthrough */
		case 2:
			item->info.companies_max = NetworkRecv_uint8(&_udp_cs, p);
			item->info.companies_on = NetworkRecv_uint8(&_udp_cs, p);
			item->info.spectators_max = NetworkRecv_uint8(&_udp_cs, p);
			/* Fallthrough */
		case 1:
			NetworkRecv_string(&_udp_cs, p, item->info.server_name, sizeof(item->info.server_name));
			NetworkRecv_string(&_udp_cs, p, item->info.server_revision, sizeof(item->info.server_revision));
			item->info.server_lang   = NetworkRecv_uint8(&_udp_cs, p);
			item->info.use_password  = NetworkRecv_uint8(&_udp_cs, p);
			item->info.clients_max   = NetworkRecv_uint8(&_udp_cs, p);
			item->info.clients_on    = NetworkRecv_uint8(&_udp_cs, p);
			item->info.spectators_on = NetworkRecv_uint8(&_udp_cs, p);
			if (game_info_version < 3) { // 16 bits dates got scrapped and are read earlier
				item->info.game_date     = NetworkRecv_uint16(&_udp_cs, p) + DAYS_TILL_ORIGINAL_BASE_YEAR;
				item->info.start_date    = NetworkRecv_uint16(&_udp_cs, p) + DAYS_TILL_ORIGINAL_BASE_YEAR;
			}
			NetworkRecv_string(&_udp_cs, p, item->info.map_name, sizeof(item->info.map_name));
			item->info.map_width     = NetworkRecv_uint16(&_udp_cs, p);
			item->info.map_height    = NetworkRecv_uint16(&_udp_cs, p);
			item->info.map_set       = NetworkRecv_uint8(&_udp_cs, p);
			item->info.dedicated     = NetworkRecv_uint8(&_udp_cs, p);

			if (item->info.server_lang >= NETWORK_NUM_LANGUAGES) item->info.server_lang = 0;
			if (item->info.map_set >= NUM_LANDSCAPE ) item->info.map_set = 0;

			if (item->info.hostname[0] == '\0')
				snprintf(item->info.hostname, sizeof(item->info.hostname), "%s", inet_ntoa(client_addr->sin_addr));

			/* Check if we are allowed on this server based on the revision-match */
			item->info.compatible =
				strcmp(item->info.server_revision, _openttd_revision) == 0 ||
				strcmp(item->info.server_revision, NOREV_STRING) == 0;
			break;
	}

	item->online = true;

	UpdateNetworkGameWindow(false);
}

DEF_UDP_RECEIVE_COMMAND(PACKET_UDP_CLIENT_DETAIL_INFO)
{
	NetworkClientState *cs;
	NetworkClientInfo *ci;
	Packet *packet;
	Player *player;
	byte current = 0;
	int i;

	// Just a fail-safe.. should never happen
	if (!_network_udp_server) return;

	packet = NetworkSend_Init(PACKET_UDP_SERVER_DETAIL_INFO);

	/* Send the amount of active companies */
	NetworkSend_uint8 (packet, NETWORK_COMPANY_INFO_VERSION);
	NetworkSend_uint8 (packet, ActivePlayerCount());

	/* Fetch the latest version of everything */
	NetworkPopulateCompanyInfo();

	/* Go through all the players */
	FOR_ALL_PLAYERS(player) {
		/* Skip non-active players */
		if (!player->is_active) continue;

		current++;

		/* Send the information */
		NetworkSend_uint8(packet, current);

		NetworkSend_string(packet, _network_player_info[player->index].company_name);
		NetworkSend_uint32(packet, _network_player_info[player->index].inaugurated_year);
		NetworkSend_uint64(packet, _network_player_info[player->index].company_value);
		NetworkSend_uint64(packet, _network_player_info[player->index].money);
		NetworkSend_uint64(packet, _network_player_info[player->index].income);
		NetworkSend_uint16(packet, _network_player_info[player->index].performance);

		/* Send 1 if there is a passord for the company else send 0 */
		if (_network_player_info[player->index].password[0] != '\0') {
			NetworkSend_uint8(packet, 1);
		} else {
			NetworkSend_uint8(packet, 0);
		}

		for (i = 0; i < NETWORK_VEHICLE_TYPES; i++)
			NetworkSend_uint16(packet, _network_player_info[player->index].num_vehicle[i]);

		for (i = 0; i < NETWORK_STATION_TYPES; i++)
			NetworkSend_uint16(packet, _network_player_info[player->index].num_station[i]);

		/* Find the clients that are connected to this player */
		FOR_ALL_CLIENTS(cs) {
			ci = DEREF_CLIENT_INFO(cs);
			if (ci->client_playas == player->index) {
				/* The uint8 == 1 indicates that a client is following */
				NetworkSend_uint8(packet, 1);
				NetworkSend_string(packet, ci->client_name);
				NetworkSend_string(packet, ci->unique_id);
				NetworkSend_uint32(packet, ci->join_date);
			}
		}
		/* Also check for the server itself */
		ci = NetworkFindClientInfoFromIndex(NETWORK_SERVER_INDEX);
		if (ci->client_playas == player->index) {
			/* The uint8 == 1 indicates that a client is following */
			NetworkSend_uint8(packet, 1);
			NetworkSend_string(packet, ci->client_name);
			NetworkSend_string(packet, ci->unique_id);
			NetworkSend_uint32(packet, ci->join_date);
		}

		/* Indicates end of client list */
		NetworkSend_uint8(packet, 0);
	}

	/* And check if we have any spectators */
	FOR_ALL_CLIENTS(cs) {
		ci = DEREF_CLIENT_INFO(cs);
		if (!IsValidPlayer(ci->client_playas)) {
			/* The uint8 == 1 indicates that a client is following */
			NetworkSend_uint8(packet, 1);
			NetworkSend_string(packet, ci->client_name);
			NetworkSend_string(packet, ci->unique_id);
			NetworkSend_uint32(packet, ci->join_date);
		}
	}

	/* Also check for the server itself */
	ci = NetworkFindClientInfoFromIndex(NETWORK_SERVER_INDEX);
	if (!IsValidPlayer(ci->client_playas)) {
		/* The uint8 == 1 indicates that a client is following */
		NetworkSend_uint8(packet, 1);
		NetworkSend_string(packet, ci->client_name);
		NetworkSend_string(packet, ci->unique_id);
		NetworkSend_uint32(packet, ci->join_date);
	}

	/* Indicates end of client list */
	NetworkSend_uint8(packet, 0);

	NetworkSendUDP_Packet(_udp_server_socket, packet, client_addr);

	free(packet);
}

DEF_UDP_RECEIVE_COMMAND(PACKET_UDP_MASTER_RESPONSE_LIST)
{
	int i;
	struct in_addr ip;
	uint16 port;
	uint8 ver;

	/* packet begins with the protocol version (uint8)
	 * then an uint16 which indicates how many
	 * ip:port pairs are in this packet, after that
	 * an uint32 (ip) and an uint16 (port) for each pair
	 */

	ver = NetworkRecv_uint8(&_udp_cs, p);

	if (_udp_cs.has_quit) return;

	if (ver == 1) {
		for (i = NetworkRecv_uint16(&_udp_cs, p); i != 0 ; i--) {
			ip.s_addr = TO_LE32(NetworkRecv_uint32(&_udp_cs, p));
			port = NetworkRecv_uint16(&_udp_cs, p);
			NetworkUDPQueryServer(inet_ntoa(ip), port);
		}
	}
}

DEF_UDP_RECEIVE_COMMAND(PACKET_UDP_MASTER_ACK_REGISTER)
{
	_network_advertise_retries = 0;
	DEBUG(net, 2)("[NET][UDP] We are advertised on the master-server!");

	if (!_network_advertise) {
		/* We are advertised, but we don't want to! */
		NetworkUDPRemoveAdvertise();
	}
}


// The layout for the receive-functions by UDP
typedef void NetworkUDPPacket(Packet *p, struct sockaddr_in *client_addr);

static NetworkUDPPacket* const _network_udp_packet[] = {
	RECEIVE_COMMAND(PACKET_UDP_CLIENT_FIND_SERVER),
	RECEIVE_COMMAND(PACKET_UDP_SERVER_RESPONSE),
	RECEIVE_COMMAND(PACKET_UDP_CLIENT_DETAIL_INFO),
	NULL,
	NULL,
	RECEIVE_COMMAND(PACKET_UDP_MASTER_ACK_REGISTER),
	NULL,
	RECEIVE_COMMAND(PACKET_UDP_MASTER_RESPONSE_LIST),
	NULL
};


// If this fails, check the array above with network_data.h
assert_compile(lengthof(_network_udp_packet) == PACKET_UDP_END);


static void NetworkHandleUDPPacket(Packet* p, struct sockaddr_in* client_addr)
{
	byte type;

	/* Fake a client, so we can see when there is an illegal packet */
	_udp_cs.socket = INVALID_SOCKET;
	_udp_cs.has_quit = false;

	type = NetworkRecv_uint8(&_udp_cs, p);

	if (type < PACKET_UDP_END && _network_udp_packet[type] != NULL && !_udp_cs.has_quit) {
		_network_udp_packet[type](p, client_addr);
	} else {
		if (!_udp_cs.has_quit) {
			DEBUG(net, 0)("[NET][UDP] Received invalid packet type %d", type);
		} else {
			DEBUG(net, 0)("[NET][UDP] Received illegal packet");
		}
	}
}


// Send a packet over UDP
static void NetworkSendUDP_Packet(SOCKET udp, Packet* p, struct sockaddr_in* recv)
{
	int res;

	// Put the length in the buffer
	p->buffer[0] = p->size & 0xFF;
	p->buffer[1] = p->size >> 8;

	// Send the buffer
	res = sendto(udp, p->buffer, p->size, 0, (struct sockaddr *)recv, sizeof(*recv));

	// Check for any errors, but ignore it for the rest
	if (res == -1) {
		DEBUG(net, 1)("[NET][UDP] Send error: %i", GET_LAST_ERROR());
	}
}

// Start UDP listener
bool NetworkUDPListen(SOCKET *udp, uint32 host, uint16 port, bool broadcast)
{
	struct sockaddr_in sin;

	// Make sure socket is closed
	closesocket(*udp);

	*udp = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
	if (*udp == INVALID_SOCKET) {
		DEBUG(net, 1)("[NET][UDP] Failed to start UDP support");
		return false;
	}

	// set nonblocking mode for socket
	{
		unsigned long blocking = 1;
#ifndef BEOS_NET_SERVER
		ioctlsocket(*udp, FIONBIO, &blocking);
#else
		setsockopt(*udp, SOL_SOCKET, SO_NONBLOCK, &blocking, NULL);
#endif
	}

	sin.sin_family = AF_INET;
	// Listen on all IPs
	sin.sin_addr.s_addr = host;
	sin.sin_port = htons(port);

	if (bind(*udp, (struct sockaddr*)&sin, sizeof(sin)) != 0) {
		DEBUG(net, 1) ("[NET][UDP] error: bind failed on %s:%i", inet_ntoa(*(struct in_addr *)&host), port);
		return false;
	}

	if (broadcast) {
		/* Enable broadcast */
		unsigned long val = 1;
#ifndef BEOS_NET_SERVER // will work around this, some day; maybe.
		setsockopt(*udp, SOL_SOCKET, SO_BROADCAST, (char *) &val , sizeof(val));
#endif
	}

	DEBUG(net, 1)("[NET][UDP] Listening on port %s:%d", inet_ntoa(*(struct in_addr *)&host), port);

	return true;
}

// Close UDP connection
void NetworkUDPClose(void)
{
	DEBUG(net, 1) ("[NET][UDP] Closed listeners");

	if (_network_udp_server) {
		if (_udp_server_socket != INVALID_SOCKET) {
			closesocket(_udp_server_socket);
			_udp_server_socket = INVALID_SOCKET;
		}

		if (_udp_master_socket != INVALID_SOCKET) {
			closesocket(_udp_master_socket);
			_udp_master_socket = INVALID_SOCKET;
		}

		_network_udp_server = false;
		_network_udp_broadcast = 0;
	} else {
		if (_udp_client_socket != INVALID_SOCKET) {
			closesocket(_udp_client_socket);
			_udp_client_socket = INVALID_SOCKET;
		}
		_network_udp_broadcast = 0;
	}
}

// Receive something on UDP level
void NetworkUDPReceive(SOCKET udp)
{
	struct sockaddr_in client_addr;
	socklen_t client_len;
	int nbytes;
	static Packet *p = NULL;
	int packet_len;

	// If p is NULL, malloc him.. this prevents unneeded mallocs
	if (p == NULL) p = malloc(sizeof(*p));

	packet_len = sizeof(p->buffer);
	client_len = sizeof(client_addr);

	// Try to receive anything
	nbytes = recvfrom(udp, p->buffer, packet_len, 0, (struct sockaddr *)&client_addr, &client_len);

	// We got some bytes.. just asume we receive the whole packet
	if (nbytes > 0) {
		// Get the size of the buffer
		p->size = (uint16)p->buffer[0];
		p->size += (uint16)p->buffer[1] << 8;
		// Put the position on the right place
		p->pos = 2;
		p->next = NULL;

		// Handle the packet
		NetworkHandleUDPPacket(p, &client_addr);

		// Free the packet
		free(p);
		p = NULL;
	}
}

// Broadcast to all ips
static void NetworkUDPBroadCast(SOCKET udp)
{
	Packet* p = NetworkSend_Init(PACKET_UDP_CLIENT_FIND_SERVER);
	uint i;

	for (i = 0; _broadcast_list[i] != 0; i++) {
		struct sockaddr_in out_addr;

		out_addr.sin_family = AF_INET;
		out_addr.sin_port = htons(_network_server_port);
		out_addr.sin_addr.s_addr = _broadcast_list[i];

		DEBUG(net, 6)("[NET][UDP] Broadcasting to %s", inet_ntoa(out_addr.sin_addr));

		NetworkSendUDP_Packet(udp, p, &out_addr);
	}

	free(p);
}


// Request the the server-list from the master server
void NetworkUDPQueryMasterServer(void)
{
	struct sockaddr_in out_addr;
	Packet *p;

	if (_udp_client_socket == INVALID_SOCKET)
		if (!NetworkUDPListen(&_udp_client_socket, 0, 0, true))
			return;

	p = NetworkSend_Init(PACKET_UDP_CLIENT_GET_LIST);

	out_addr.sin_family = AF_INET;
	out_addr.sin_port = htons(NETWORK_MASTER_SERVER_PORT);
	out_addr.sin_addr.s_addr = NetworkResolveHost(NETWORK_MASTER_SERVER_HOST);

	// packet only contains protocol version
	NetworkSend_uint8(p, NETWORK_MASTER_SERVER_VERSION);

	NetworkSendUDP_Packet(_udp_client_socket, p, &out_addr);

	DEBUG(net, 2)("[NET][UDP] Queried Master Server at %s:%d", inet_ntoa(out_addr.sin_addr),ntohs(out_addr.sin_port));

	free(p);
}

// Find all servers
void NetworkUDPSearchGame(void)
{
	// We are still searching..
	if (_network_udp_broadcast > 0)
		return;

	// No UDP-socket yet..
	if (_udp_client_socket == INVALID_SOCKET)
		if (!NetworkUDPListen(&_udp_client_socket, 0, 0, true))
			return;

	DEBUG(net, 0)("[NET][UDP] Searching server");

	NetworkUDPBroadCast(_udp_client_socket);
	_network_udp_broadcast = 300; // Stay searching for 300 ticks
}

NetworkGameList *NetworkUDPQueryServer(const char* host, unsigned short port)
{
	struct sockaddr_in out_addr;
	Packet *p;
	NetworkGameList *item;

	// No UDP-socket yet..
	if (_udp_client_socket == INVALID_SOCKET)
		if (!NetworkUDPListen(&_udp_client_socket, 0, 0, true))
			return NULL;

	out_addr.sin_family = AF_INET;
	out_addr.sin_port = htons(port);
	out_addr.sin_addr.s_addr = NetworkResolveHost(host);

	// Clear item in gamelist
	item = NetworkGameListAddItem(inet_addr(inet_ntoa(out_addr.sin_addr)), ntohs(out_addr.sin_port));
	memset(&item->info, 0, sizeof(item->info));
	ttd_strlcpy(item->info.server_name, host, lengthof(item->info.server_name));
	ttd_strlcpy(item->info.hostname, host, lengthof(item->info.hostname));
	item->online = false;

	// Init the packet
	p = NetworkSend_Init(PACKET_UDP_CLIENT_FIND_SERVER);

	NetworkSendUDP_Packet(_udp_client_socket, p, &out_addr);

	free(p);

	UpdateNetworkGameWindow(false);
	return item;
}

/* Remove our advertise from the master-server */
void NetworkUDPRemoveAdvertise(void)
{
	struct sockaddr_in out_addr;
	Packet *p;

	/* Check if we are advertising */
	if (!_networking || !_network_server || !_network_udp_server)
		return;

	/* check for socket */
	if (_udp_master_socket == INVALID_SOCKET)
		if (!NetworkUDPListen(&_udp_master_socket, _network_server_bind_ip, 0, false))
			return;

	DEBUG(net, 2)("[NET][UDP] Removing advertise..");

	/* Find somewhere to send */
	out_addr.sin_family = AF_INET;
	out_addr.sin_port = htons(NETWORK_MASTER_SERVER_PORT);
	out_addr.sin_addr.s_addr = NetworkResolveHost(NETWORK_MASTER_SERVER_HOST);

	/* Send the packet */
	p = NetworkSend_Init(PACKET_UDP_SERVER_UNREGISTER);
	/* Packet is: Version, server_port */
	NetworkSend_uint8(p, NETWORK_MASTER_SERVER_VERSION);
	NetworkSend_uint16(p, _network_server_port);
	NetworkSendUDP_Packet(_udp_master_socket, p, &out_addr);

	free(p);
}

/* Register us to the master server
     This function checks if it needs to send an advertise */
void NetworkUDPAdvertise(void)
{
	struct sockaddr_in out_addr;
	Packet *p;

	/* Check if we should send an advertise */
	if (!_networking || !_network_server || !_network_udp_server || !_network_advertise)
		return;

	/* check for socket */
	if (_udp_master_socket == INVALID_SOCKET)
		if (!NetworkUDPListen(&_udp_master_socket, _network_server_bind_ip, 0, false))
			return;

	if (_network_need_advertise) {
		_network_need_advertise = false;
		_network_advertise_retries = ADVERTISE_RETRY_TIMES;
	} else {
		/* Only send once every ADVERTISE_NORMAL_INTERVAL ticks */
		if (_network_advertise_retries == 0) {
			if ((_network_last_advertise_frame + ADVERTISE_NORMAL_INTERVAL) > _frame_counter)
				return;
			_network_advertise_retries = ADVERTISE_RETRY_TIMES;
		}

		if ((_network_last_advertise_frame + ADVERTISE_RETRY_INTERVAL) > _frame_counter)
			return;
	}

	_network_advertise_retries--;
	_network_last_advertise_frame = _frame_counter;

	/* Find somewhere to send */
	out_addr.sin_family = AF_INET;
	out_addr.sin_port = htons(NETWORK_MASTER_SERVER_PORT);
	out_addr.sin_addr.s_addr = NetworkResolveHost(NETWORK_MASTER_SERVER_HOST);

	DEBUG(net, 1)("[NET][UDP] Advertising to master server");

	/* Send the packet */
	p = NetworkSend_Init(PACKET_UDP_SERVER_REGISTER);
	/* Packet is: WELCOME_MESSAGE, Version, server_port */
	NetworkSend_string(p, NETWORK_MASTER_SERVER_WELCOME_MESSAGE);
	NetworkSend_uint8(p, NETWORK_MASTER_SERVER_VERSION);
	NetworkSend_uint16(p, _network_server_port);
	NetworkSendUDP_Packet(_udp_master_socket, p, &out_addr);

	free(p);
}

void NetworkUDPInitialize(void)
{
	_udp_client_socket = INVALID_SOCKET;
	_udp_server_socket = INVALID_SOCKET;
	_udp_master_socket = INVALID_SOCKET;

	_network_udp_server = false;
	_network_udp_broadcast = 0;
}

#endif /* ENABLE_NETWORK */