summaryrefslogtreecommitdiff
path: root/src/network/network.cpp
blob: 050b644ba1b278ecce623d09953af82bb9ae2d7b (plain)
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
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
/* $Id$ */

/*
 * This file is part of OpenTTD.
 * OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2.
 * OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
 */

/** @file network.cpp Base functions for networking support. */

#include "../stdafx.h"

#ifdef ENABLE_NETWORK

#include "../strings_func.h"
#include "../command_func.h"
#include "../date_func.h"
#include "network_admin.h"
#include "network_client.h"
#include "network_server.h"
#include "network_content.h"
#include "network_udp.h"
#include "network_gamelist.h"
#include "network_base.h"
#include "core/udp.h"
#include "core/host.h"
#include "network_gui.h"
#include "../console_func.h"
#include "../3rdparty/md5/md5.h"
#include "../core/random_func.hpp"
#include "../window_func.h"
#include "../company_func.h"
#include "../company_base.h"
#include "../landscape_type.h"
#include "../rev.h"
#include "../core/pool_func.hpp"
#include "../gfx_func.h"
#include "table/strings.h"

#ifdef DEBUG_DUMP_COMMANDS
#include "../fileio_func.h"
/** When running the server till the wait point, run as fast as we can! */
bool _ddc_fastforward = true;
#endif /* DEBUG_DUMP_COMMANDS */

assert_compile(NetworkClientInfoPool::MAX_SIZE == NetworkClientSocketPool::MAX_SIZE);

NetworkClientInfoPool _networkclientinfo_pool("NetworkClientInfo");
INSTANTIATE_POOL_METHODS(NetworkClientInfo)

bool _networking;         ///< are we in networking mode?
bool _network_server;     ///< network-server is active
bool _network_available;  ///< is network mode available?
bool _network_dedicated;  ///< are we a dedicated server?
bool _is_network_server;  ///< Does this client wants to be a network-server?
NetworkServerGameInfo _network_game_info;
NetworkCompanyState *_network_company_states = NULL;
ClientID _network_own_client_id;
ClientID _redirect_console_to_client;
bool _network_need_advertise;
uint32 _network_last_advertise_frame;
uint8 _network_reconnect;
StringList _network_bind_list;
StringList _network_host_list;
StringList _network_ban_list;
uint32 _frame_counter_server; // The frame_counter of the server, if in network-mode
uint32 _frame_counter_max; // To where we may go with our clients
uint32 _frame_counter;
uint32 _last_sync_frame; // Used in the server to store the last time a sync packet was sent to clients.
NetworkAddressList _broadcast_list;
uint32 _sync_seed_1;
#ifdef NETWORK_SEND_DOUBLE_SEED
uint32 _sync_seed_2;
#endif
uint32 _sync_frame;
bool _network_first_time;
bool _network_udp_server;
uint16 _network_udp_broadcast;
uint8 _network_advertise_retries;
CompanyMask _network_company_passworded; ///< Bitmask of the password status of all companies.

/* Check whether NETWORK_NUM_LANDSCAPES is still in sync with NUM_LANDSCAPE */
assert_compile((int)NETWORK_NUM_LANDSCAPES == (int)NUM_LANDSCAPE);
assert_compile((int)NETWORK_COMPANY_NAME_LENGTH == MAX_LENGTH_COMPANY_NAME_BYTES);

extern NetworkUDPSocketHandler *_udp_client_socket; ///< udp client socket
extern NetworkUDPSocketHandler *_udp_server_socket; ///< udp server socket
extern NetworkUDPSocketHandler *_udp_master_socket; ///< udp master socket

/* The amount of clients connected */
byte _network_clients_connected = 0;

/* Some externs / forwards */
extern void StateGameLoop();

/**
 * Basically a client is leaving us right now.
 */
NetworkClientInfo::~NetworkClientInfo()
{
	/* Delete the chat window, if you were chatting with this client. */
	InvalidateWindowData(WC_SEND_NETWORK_MSG, DESTTYPE_CLIENT, this->client_id);
}

/**
 * Return the CI given it's client-identifier
 * @param client_id the ClientID to search for
 * @return return a pointer to the corresponding NetworkClientInfo struct or NULL when not found
 */
NetworkClientInfo *NetworkFindClientInfoFromClientID(ClientID client_id)
{
	NetworkClientInfo *ci;

	FOR_ALL_CLIENT_INFOS(ci) {
		if (ci->client_id == client_id) return ci;
	}

	return NULL;
}

/**
 * Return the client state given it's client-identifier
 * @param client_id the ClientID to search for
 * @return return a pointer to the corresponding NetworkClientSocket struct or NULL when not found
 */
NetworkClientSocket *NetworkFindClientStateFromClientID(ClientID client_id)
{
	NetworkClientSocket *cs;

	FOR_ALL_CLIENT_SOCKETS(cs) {
		if (cs->client_id == client_id) return cs;
	}

	return NULL;
}

byte NetworkSpectatorCount()
{
	const NetworkClientInfo *ci;
	byte count = 0;

	FOR_ALL_CLIENT_INFOS(ci) {
		if (ci->client_playas == COMPANY_SPECTATOR) count++;
	}

	/* Don't count a dedicated server as spectator */
	if (_network_dedicated) count--;

	return count;
}

/**
 * Check if the company we want to join requires a password.
 * @param company_id id of the company we want to check the 'passworded' flag for.
 * @return true if the company requires a password.
 */
bool NetworkCompanyIsPassworded(CompanyID company_id)
{
	return HasBit(_network_company_passworded, company_id);
}

/* This puts a text-message to the console, or in the future, the chat-box,
 *  (to keep it all a bit more general)
 * If 'self_send' is true, this is the client who is sending the message */
void NetworkTextMessage(NetworkAction action, ConsoleColour colour, bool self_send, const char *name, const char *str, int64 data)
{
	const int duration = 10; // Game days the messages stay visible

	StringID strid;
	switch (action) {
		case NETWORK_ACTION_SERVER_MESSAGE:
			/* Ignore invalid messages */
			strid = STR_NETWORK_SERVER_MESSAGE;
			colour = CC_DEFAULT;
			break;
		case NETWORK_ACTION_COMPANY_SPECTATOR:
			colour = CC_DEFAULT;
			strid = STR_NETWORK_MESSAGE_CLIENT_COMPANY_SPECTATE;
			break;
		case NETWORK_ACTION_COMPANY_JOIN:
			colour = CC_DEFAULT;
			strid = STR_NETWORK_MESSAGE_CLIENT_COMPANY_JOIN;
			break;
		case NETWORK_ACTION_COMPANY_NEW:
			colour = CC_DEFAULT;
			strid = STR_NETWORK_MESSAGE_CLIENT_COMPANY_NEW;
			break;
		case NETWORK_ACTION_JOIN:
			/* Show the Client ID for the server but not for the client. */
			strid = _network_server ? STR_NETWORK_MESSAGE_CLIENT_JOINED_ID :  STR_NETWORK_MESSAGE_CLIENT_JOINED;
			break;
		case NETWORK_ACTION_LEAVE:          strid = STR_NETWORK_MESSAGE_CLIENT_LEFT; break;
		case NETWORK_ACTION_NAME_CHANGE:    strid = STR_NETWORK_MESSAGE_NAME_CHANGE; break;
		case NETWORK_ACTION_GIVE_MONEY:     strid = self_send ? STR_NETWORK_MESSAGE_GAVE_MONEY_AWAY : STR_NETWORK_MESSAGE_GIVE_MONEY;   break;
		case NETWORK_ACTION_CHAT_COMPANY:   strid = self_send ? STR_NETWORK_CHAT_TO_COMPANY : STR_NETWORK_CHAT_COMPANY; break;
		case NETWORK_ACTION_CHAT_CLIENT:    strid = self_send ? STR_NETWORK_CHAT_TO_CLIENT  : STR_NETWORK_CHAT_CLIENT;  break;
		default:                            strid = STR_NETWORK_CHAT_ALL; break;
	}

	char message[1024];
	SetDParamStr(0, name);
	SetDParamStr(1, str);
	SetDParam(2, data);

	/* All of these strings start with "***". These characters are interpreted as both left-to-right and
	 * right-to-left characters depending on the context. As the next text might be an user's name, the
	 * user name's characters will influence the direction of the "***" instead of the language setting
	 * of the game. Manually set the direction of the "***" by inserting a text-direction marker. */
	char *msg_ptr = message + Utf8Encode(message, _current_text_dir == TD_LTR ? CHAR_TD_LRM : CHAR_TD_RLM);
	GetString(msg_ptr, strid, lastof(message));

	DEBUG(desync, 1, "msg: %08x; %02x; %s", _date, _date_fract, message);
	IConsolePrintF(colour, "%s", message);
	NetworkAddChatMessage((TextColour)colour, duration, "%s", message);
}

/* Calculate the frame-lag of a client */
uint NetworkCalculateLag(const NetworkClientSocket *cs)
{
	int lag = cs->last_frame_server - cs->last_frame;
	/* This client has missed his ACK packet after 1 DAY_TICKS..
	 *  so we increase his lag for every frame that passes!
	 * The packet can be out by a max of _net_frame_freq */
	if (cs->last_frame_server + DAY_TICKS + _settings_client.network.frame_freq < _frame_counter) {
		lag += _frame_counter - (cs->last_frame_server + DAY_TICKS + _settings_client.network.frame_freq);
	}
	return lag;
}


/* There was a non-recoverable error, drop back to the main menu with a nice
 *  error */
void NetworkError(StringID error_string)
{
	_switch_mode = SM_MENU;
	extern StringID _switch_mode_errorstr;
	_switch_mode_errorstr = error_string;
}

/**
 * Retrieve the string id of an internal error number
 * @param err NetworkErrorCode
 * @return the StringID
 */
StringID GetNetworkErrorMsg(NetworkErrorCode err)
{
	/* List of possible network errors, used by
	 * PACKET_SERVER_ERROR and PACKET_CLIENT_ERROR */
	static const StringID network_error_strings[] = {
		STR_NETWORK_ERROR_CLIENT_GENERAL,
		STR_NETWORK_ERROR_CLIENT_DESYNC,
		STR_NETWORK_ERROR_CLIENT_SAVEGAME,
		STR_NETWORK_ERROR_CLIENT_CONNECTION_LOST,
		STR_NETWORK_ERROR_CLIENT_PROTOCOL_ERROR,
		STR_NETWORK_ERROR_CLIENT_NEWGRF_MISMATCH,
		STR_NETWORK_ERROR_CLIENT_NOT_AUTHORIZED,
		STR_NETWORK_ERROR_CLIENT_NOT_EXPECTED,
		STR_NETWORK_ERROR_CLIENT_WRONG_REVISION,
		STR_NETWORK_ERROR_CLIENT_NAME_IN_USE,
		STR_NETWORK_ERROR_CLIENT_WRONG_PASSWORD,
		STR_NETWORK_ERROR_CLIENT_COMPANY_MISMATCH,
		STR_NETWORK_ERROR_CLIENT_KICKED,
		STR_NETWORK_ERROR_CLIENT_CHEATER,
		STR_NETWORK_ERROR_CLIENT_SERVER_FULL,
		STR_NETWORK_ERROR_CLIENT_TOO_MANY_COMMANDS
	};

	if (err >= (ptrdiff_t)lengthof(network_error_strings)) err = NETWORK_ERROR_GENERAL;

	return network_error_strings[err];
}

/**
 * Handle the pause mode change so we send the right messages to the chat.
 * @param prev_mode The previous pause mode.
 * @param changed_mode The pause mode that got changed.
 */
void NetworkHandlePauseChange(PauseMode prev_mode, PauseMode changed_mode)
{
	if (!_networking) return;

	switch (changed_mode) {
		case PM_PAUSED_NORMAL:
		case PM_PAUSED_JOIN:
		case PM_PAUSED_ACTIVE_CLIENTS: {
			bool changed = ((_pause_mode == PM_UNPAUSED) != (prev_mode == PM_UNPAUSED));
			bool paused = (_pause_mode != PM_UNPAUSED);
			if (!paused && !changed) return;

			StringID str;
			if (!changed) {
				int i = -1;
				if ((_pause_mode & PM_PAUSED_NORMAL) != PM_UNPAUSED)         SetDParam(++i, STR_NETWORK_SERVER_MESSAGE_GAME_REASON_MANUAL);
				if ((_pause_mode & PM_PAUSED_JOIN) != PM_UNPAUSED)           SetDParam(++i, STR_NETWORK_SERVER_MESSAGE_GAME_REASON_CONNECTING_CLIENTS);
				if ((_pause_mode & PM_PAUSED_ACTIVE_CLIENTS) != PM_UNPAUSED) SetDParam(++i, STR_NETWORK_SERVER_MESSAGE_GAME_REASON_NOT_ENOUGH_PLAYERS);
				str = STR_NETWORK_SERVER_MESSAGE_GAME_STILL_PAUSED_1 + i;
			} else {
				switch (changed_mode) {
					case PM_PAUSED_NORMAL:         SetDParam(0, STR_NETWORK_SERVER_MESSAGE_GAME_REASON_MANUAL); break;
					case PM_PAUSED_JOIN:           SetDParam(0, STR_NETWORK_SERVER_MESSAGE_GAME_REASON_CONNECTING_CLIENTS); break;
					case PM_PAUSED_ACTIVE_CLIENTS: SetDParam(0, STR_NETWORK_SERVER_MESSAGE_GAME_REASON_NOT_ENOUGH_PLAYERS); break;
					default: NOT_REACHED();
				}
				str = paused ? STR_NETWORK_SERVER_MESSAGE_GAME_PAUSED : STR_NETWORK_SERVER_MESSAGE_GAME_UNPAUSED;
			}

			char buffer[DRAW_STRING_BUFFER];
			GetString(buffer, str, lastof(buffer));
			NetworkTextMessage(NETWORK_ACTION_SERVER_MESSAGE, CC_DEFAULT, false, NULL, buffer);
			break;
		}

		default:
			return;
	}
}


/**
 * Helper function for the pause checkers. If pause is true and the
 * current pause mode isn't set the game will be paused, if it it false
 * and the pause mode is set the game will be unpaused. In the other
 * cases nothing happens to the pause state.
 * @param pause whether we'd like to pause
 * @param pm the mode which we would like to pause with
 */
static void CheckPauseHelper(bool pause, PauseMode pm)
{
	if (pause == ((_pause_mode & pm) != PM_UNPAUSED)) return;

	DoCommandP(0, pm, pause ? 1 : 0, CMD_PAUSE);
}

/**
 * Counts the number of active clients connected.
 * It has to be in STATUS_ACTIVE and not a spectator
 * @return number of active clients
 */
static uint NetworkCountActiveClients()
{
	const NetworkClientSocket *cs;
	uint count = 0;

	FOR_ALL_CLIENT_SOCKETS(cs) {
		if (cs->status != NetworkClientSocket::STATUS_ACTIVE) continue;
		if (!Company::IsValidID(cs->GetInfo()->client_playas)) continue;
		count++;
	}

	return count;
}

/**
 * Check if the minimum number of active clients has been reached and pause or unpause the game as appropriate
 */
static void CheckMinActiveClients()
{
	if ((_pause_mode & PM_PAUSED_ERROR) != PM_UNPAUSED ||
			!_network_dedicated ||
			(_settings_client.network.min_active_clients == 0 && (_pause_mode & PM_PAUSED_ACTIVE_CLIENTS) == PM_UNPAUSED)) {
		return;
	}
	CheckPauseHelper(NetworkCountActiveClients() < _settings_client.network.min_active_clients, PM_PAUSED_ACTIVE_CLIENTS);
}

/**
 * Checks whether there is a joining client
 * @return true iff one client is joining (but not authorizing)
 */
static bool NetworkHasJoiningClient()
{
	const NetworkClientSocket *cs;
	FOR_ALL_CLIENT_SOCKETS(cs) {
		if (cs->status >= NetworkClientSocket::STATUS_AUTHORIZED && cs->status < NetworkClientSocket::STATUS_ACTIVE) return true;
	}

	return false;
}

/**
 * Check whether we should pause on join
 */
static void CheckPauseOnJoin()
{
	if ((_pause_mode & PM_PAUSED_ERROR) != PM_UNPAUSED ||
			(!_settings_client.network.pause_on_join && (_pause_mode & PM_PAUSED_JOIN) == PM_UNPAUSED)) {
		return;
	}
	CheckPauseHelper(NetworkHasJoiningClient(), PM_PAUSED_JOIN);
}

/**
 * Converts a string to ip/port/company
 *  Format: IP:port#company
 *
 * connection_string will be re-terminated to seperate out the hostname, and company and port will
 * be set to the company and port strings given by the user, inside the memory area originally
 * occupied by connection_string.
 */
void ParseConnectionString(const char **company, const char **port, char *connection_string)
{
	bool ipv6 = (strchr(connection_string, ':') != strrchr(connection_string, ':'));
	char *p;
	for (p = connection_string; *p != '\0'; p++) {
		switch (*p) {
			case '[':
				ipv6 = true;
				break;

			case ']':
				ipv6 = false;
				break;

			case '#':
				*company = p + 1;
				*p = '\0';
				break;

			case ':':
				if (ipv6) break;
				*port = p + 1;
				*p = '\0';
				break;
		}
	}
}

/* static */ void ServerNetworkGameSocketHandler::AcceptConnection(SOCKET s, const NetworkAddress &address)
{
	/* Register the login */
	_network_clients_connected++;

	SetWindowDirty(WC_CLIENT_LIST, 0);
	ServerNetworkGameSocketHandler *cs = new ServerNetworkGameSocketHandler(s);
	cs->GetInfo()->client_address = address; // Save the IP of the client
}

/**
 * Resets the pools used for network clients, and the admin pool if needed.
 * @param close_admins Whether the admin pool has to be cleared as well.
 */
static void InitializeNetworkPools(bool close_admins = true)
{
	_networkclientsocket_pool.CleanPool();
	_networkclientinfo_pool.CleanPool();
	if (close_admins) _networkadminsocket_pool.CleanPool();
}

/**
 * Close current connections.
 * @param close_admins Whether the admin connections have to be closed as well.
 */
void NetworkClose(bool close_admins)
{
	if (_network_server) {
		if (close_admins) {
			ServerNetworkAdminSocketHandler *as;
			FOR_ALL_ADMIN_SOCKETS(as) {
				as->CloseConnection(true);
			}
		}

		NetworkClientSocket *cs;
		FOR_ALL_CLIENT_SOCKETS(cs) {
			cs->CloseConnection(NETWORK_RECV_STATUS_CONN_LOST);
		}
		ServerNetworkGameSocketHandler::CloseListeners();
		ServerNetworkAdminSocketHandler::CloseListeners();
	} else if (MyClient::my_client != NULL) {
		MyClient::SendQuit();
		MyClient::my_client->CloseConnection(NETWORK_RECV_STATUS_CONN_LOST);
	}

	TCPConnecter::KillAll();

	_networking = false;
	_network_server = false;

	NetworkFreeLocalCommandQueue();

	free(_network_company_states);
	_network_company_states = NULL;

	InitializeNetworkPools(close_admins);
}

/* Inits the network (cleans sockets and stuff) */
static void NetworkInitialize(bool close_admins = true)
{
	InitializeNetworkPools(close_admins);
	NetworkUDPInitialize();

	_sync_frame = 0;
	_network_first_time = true;

	_network_reconnect = 0;
}

/** Non blocking connection create to query servers */
class TCPQueryConnecter : TCPConnecter {
public:
	TCPQueryConnecter(const NetworkAddress &address) : TCPConnecter(address) {}

	virtual void OnFailure()
	{
		NetworkDisconnect();
	}

	virtual void OnConnect(SOCKET s)
	{
		_networking = true;
		new ClientNetworkGameSocketHandler(s);
		MyClient::SendCompanyInformationQuery();
	}
};

/* Query a server to fetch his game-info
 *  If game_info is true, only the gameinfo is fetched,
 *   else only the client_info is fetched */
void NetworkTCPQueryServer(NetworkAddress address)
{
	if (!_network_available) return;

	NetworkDisconnect();
	NetworkInitialize();

	new TCPQueryConnecter(address);
}

/* Validates an address entered as a string and adds the server to
 * the list. If you use this function, the games will be marked
 * as manually added. */
void NetworkAddServer(const char *b)
{
	if (*b != '\0') {
		const char *port = NULL;
		const char *company = NULL;
		char host[NETWORK_HOSTNAME_LENGTH];
		uint16 rport;

		strecpy(host, b, lastof(host));

		strecpy(_settings_client.network.connect_to_ip, b, lastof(_settings_client.network.connect_to_ip));
		rport = NETWORK_DEFAULT_PORT;

		ParseConnectionString(&company, &port, host);
		if (port != NULL) rport = atoi(port);

		NetworkUDPQueryServer(NetworkAddress(host, rport), true);
	}
}

/**
 * Get the addresses to bind to.
 * @param addresses the list to write to.
 * @param port the port to bind to.
 */
void GetBindAddresses(NetworkAddressList *addresses, uint16 port)
{
	for (char **iter = _network_bind_list.Begin(); iter != _network_bind_list.End(); iter++) {
		*addresses->Append() = NetworkAddress(*iter, port);
	}

	/* No address, so bind to everything. */
	if (addresses->Length() == 0) {
		*addresses->Append() = NetworkAddress("", port);
	}
}

/* Generates the list of manually added hosts from NetworkGameList and
 * dumps them into the array _network_host_list. This array is needed
 * by the function that generates the config file. */
void NetworkRebuildHostList()
{
	_network_host_list.Clear();

	for (NetworkGameList *item = _network_game_list; item != NULL; item = item->next) {
		if (item->manually) *_network_host_list.Append() = strdup(item->address.GetAddressAsString(false));
	}
}

/** Non blocking connection create to actually connect to servers */
class TCPClientConnecter : TCPConnecter {
public:
	TCPClientConnecter(const NetworkAddress &address) : TCPConnecter(address) {}

	virtual void OnFailure()
	{
		NetworkError(STR_NETWORK_ERROR_NOCONNECTION);
	}

	virtual void OnConnect(SOCKET s)
	{
		_networking = true;
		new ClientNetworkGameSocketHandler(s);
		IConsoleCmdExec("exec scripts/on_client.scr 0");
		NetworkClient_Connected();
	}
};


/* Used by clients, to connect to a server */
void NetworkClientConnectGame(NetworkAddress address, CompanyID join_as, const char *join_server_password, const char *join_company_password)
{
	if (!_network_available) return;

	if (address.GetPort() == 0) return;

	strecpy(_settings_client.network.last_host, address.GetHostname(), lastof(_settings_client.network.last_host));
	_settings_client.network.last_port = address.GetPort();
	_network_join_as = join_as;
	_network_join_server_password = join_server_password;
	_network_join_company_password = join_company_password;

	NetworkDisconnect();
	NetworkInitialize();

	_network_join_status = NETWORK_JOIN_STATUS_CONNECTING;
	ShowJoinStatusWindow();

	new TCPClientConnecter(address);
}

static void NetworkInitGameInfo()
{
	if (StrEmpty(_settings_client.network.server_name)) {
		snprintf(_settings_client.network.server_name, sizeof(_settings_client.network.server_name), "Unnamed Server");
	}

	/* The server is a client too */
	_network_game_info.clients_on = _network_dedicated ? 0 : 1;

	NetworkClientInfo *ci = new NetworkClientInfo(CLIENT_ID_SERVER);
	ci->client_playas = _network_dedicated ? COMPANY_SPECTATOR : _local_company;
	/* Give the server a valid IP; banning it is pointless anyways */
	sockaddr_in sock;
	memset(&sock, 0, sizeof(sock));
	sock.sin_family = AF_INET;
	ci->client_address = NetworkAddress((sockaddr*)&sock, sizeof(sock));

	strecpy(ci->client_name, _settings_client.network.client_name, lastof(ci->client_name));
}

bool NetworkServerStart()
{
	if (!_network_available) return false;

	/* Call the pre-scripts */
	IConsoleCmdExec("exec scripts/pre_server.scr 0");
	if (_network_dedicated) IConsoleCmdExec("exec scripts/pre_dedicated.scr 0");

	NetworkDisconnect(false, false);
	NetworkInitialize(false);
	if (!ServerNetworkGameSocketHandler::Listen(_settings_client.network.server_port)) return false;

	/* Only listen for admins when the password isn't empty. */
	if (!StrEmpty(_settings_client.network.admin_password) && !ServerNetworkAdminSocketHandler::Listen(_settings_client.network.server_admin_port)) return false;

	/* Try to start UDP-server */
	_network_udp_server = _udp_server_socket->Listen();

	_network_company_states = CallocT<NetworkCompanyState>(MAX_COMPANIES);
	_network_server = true;
	_networking = true;
	_frame_counter = 0;
	_frame_counter_server = 0;
	_frame_counter_max = 0;
	_last_sync_frame = 0;
	_network_own_client_id = CLIENT_ID_SERVER;

	_network_clients_connected = 0;
	_network_company_passworded = 0;

	NetworkInitGameInfo();

	/* execute server initialization script */
	IConsoleCmdExec("exec scripts/on_server.scr 0");
	/* if the server is dedicated ... add some other script */
	if (_network_dedicated) IConsoleCmdExec("exec scripts/on_dedicated.scr 0");

	/* Try to register us to the master server */
	_network_last_advertise_frame = 0;
	_network_need_advertise = true;
	NetworkUDPAdvertise();

	/* welcome possibly still connected admins - this can only happen on a dedicated server. */
	if (_network_dedicated) ServerNetworkAdminSocketHandler::WelcomeAll();

	return true;
}

/* The server is rebooting...
 * The only difference with NetworkDisconnect, is the packets that is sent */
void NetworkReboot()
{
	if (_network_server) {
		NetworkClientSocket *cs;
		FOR_ALL_CLIENT_SOCKETS(cs) {
			cs->SendNewGame();
			cs->Send_Packets();
		}

		ServerNetworkAdminSocketHandler *as;
		FOR_ALL_ADMIN_SOCKETS(as) {
			as->SendNewGame();
			as->Send_Packets();
		}
	}

	/* For non-dedicated servers we have to kick the admins as we are not
	 * certain that we will end up in a new network game. */
	NetworkClose(!_network_dedicated);
}

/**
 * We want to disconnect from the host/clients.
 * @param blocking whether to wait till everything has been closed.
 * @param close_admins Whether the admin sockets need to be closed as well.
 */
void NetworkDisconnect(bool blocking, bool close_admins)
{
	if (_network_server) {
		NetworkClientSocket *cs;
		FOR_ALL_CLIENT_SOCKETS(cs) {
			cs->SendShutdown();
			cs->Send_Packets();
		}

		if (close_admins) {
			ServerNetworkAdminSocketHandler *as;
			FOR_ALL_ADMIN_SOCKETS(as) {
				as->SendShutdown();
				as->Send_Packets();
			}
		}
	}

	if (_settings_client.network.server_advertise) NetworkUDPRemoveAdvertise(blocking);

	DeleteWindowById(WC_NETWORK_STATUS_WINDOW, 0);

	NetworkClose(close_admins);

	/* Reinitialize the UDP stack, i.e. close all existing connections. */
	NetworkUDPInitialize();
}

/**
 * Receives something from the network.
 * @return true if everthing went fine, false when the connection got closed.
 */
static bool NetworkReceive()
{
	if (_network_server) {
		ServerNetworkAdminSocketHandler::Receive();
		return ServerNetworkGameSocketHandler::Receive();
	} else {
		return ClientNetworkGameSocketHandler::Receive();
	}
}

/* This sends all buffered commands (if possible) */
static void NetworkSend()
{
	if (_network_server) {
		ServerNetworkAdminSocketHandler::Send();
		ServerNetworkGameSocketHandler::Send();
	} else {
		ClientNetworkGameSocketHandler::Send();
	}
}

/* We have to do some UDP checking */
void NetworkUDPGameLoop()
{
	_network_content_client.SendReceive();
	TCPConnecter::CheckCallbacks();
	NetworkHTTPSocketHandler::HTTPReceive();

	if (_network_udp_server) {
		_udp_server_socket->ReceivePackets();
		_udp_master_socket->ReceivePackets();
	} else {
		_udp_client_socket->ReceivePackets();
		if (_network_udp_broadcast > 0) _network_udp_broadcast--;
		NetworkGameListRequery();
	}
}

/* The main loop called from ttd.c
 *  Here we also have to do StateGameLoop if needed! */
void NetworkGameLoop()
{
	if (!_networking) return;

	if (!NetworkReceive()) return;

	if (_network_server) {
		/* Log the sync state to check for in-syncedness of replays. */
		if (_date_fract == 0) {
			/* We don't want to log multiple times if paused. */
			static Date last_log;
			if (last_log != _date) {
				DEBUG(desync, 1, "sync: %08x; %02x; %08x; %08x", _date, _date_fract, _random.state[0], _random.state[1]);
				last_log = _date;
			}
		}

#ifdef DEBUG_DUMP_COMMANDS
		/* Loading of the debug commands from -ddesync>=1 */
		static FILE *f = FioFOpenFile("commands.log", "rb", SAVE_DIR);
		static Date next_date = 0;
		static uint32 next_date_fract;
		static CommandPacket *cp = NULL;
		static bool check_sync_state = false;
		static uint32 sync_state[2];
		if (f == NULL && next_date == 0) {
			DEBUG(net, 0, "Cannot open commands.log");
			next_date = 1;
		}

		while (f != NULL && !feof(f)) {
			if (_date == next_date && _date_fract == next_date_fract) {
				if (cp != NULL) {
					NetworkSend_Command(cp->tile, cp->p1, cp->p2, cp->cmd & ~CMD_FLAGS_MASK, NULL, cp->text, cp->company);
					DEBUG(net, 0, "injecting: %08x; %02x; %02x; %06x; %08x; %08x; %08x; \"%s\" (%s)", _date, _date_fract, (int)_current_company, cp->tile, cp->p1, cp->p2, cp->cmd, cp->text, GetCommandName(cp->cmd));
					free(cp);
					cp = NULL;
				}
				if (check_sync_state) {
					if (sync_state[0] == _random.state[0] && sync_state[1] == _random.state[1]) {
						DEBUG(net, 0, "sync check: %08x; %02x; match", _date, _date_fract);
					} else {
						DEBUG(net, 0, "sync check: %08x; %02x; mismatch expected {%08x, %08x}, got {%08x, %08x}",
									_date, _date_fract, sync_state[0], sync_state[1], _random.state[0], _random.state[1]);
						NOT_REACHED();
					}
					check_sync_state = false;
				}
			}

			if (cp != NULL || check_sync_state) break;

			char buff[4096];
			if (fgets(buff, lengthof(buff), f) == NULL) break;

			char *p = buff;
			/* Ignore the "[date time] " part of the message */
			if (*p == '[') {
				p = strchr(p, ']');
				if (p == NULL) break;
				p += 2;
			}

			if (strncmp(p, "cmd: ", 5) == 0) {
				cp = CallocT<CommandPacket>(1);
				int company;
				int ret = sscanf(p + 5, "%x; %x; %x; %x; %x; %x; %x; \"%[^\"]\"", &next_date, &next_date_fract, &company, &cp->tile, &cp->p1, &cp->p2, &cp->cmd, cp->text);
				/* There are 8 pieces of data to read, however the last is a
				 * string that might or might not exist. Ignore it if that
				 * string misses because in 99% of the time it's not used. */
				assert(ret == 8 || ret == 7);
				cp->company = (CompanyID)company;
			} else if (strncmp(p, "join: ", 6) == 0) {
				/* Manually insert a pause when joining; this way the client can join at the exact right time. */
				int ret = sscanf(p + 6, "%x; %x", &next_date, &next_date_fract);
				assert(ret == 2);
				DEBUG(net, 0, "injecting pause for join at %08x:%02x; please join when paused", next_date, next_date_fract);
				cp = CallocT<CommandPacket>(1);
				cp->company = COMPANY_SPECTATOR;
				cp->cmd = CMD_PAUSE;
				cp->p1 = PM_PAUSED_NORMAL;
				cp->p2 = 1;
				_ddc_fastforward = false;
			} else if (strncmp(p, "sync: ", 6) == 0) {
				int ret = sscanf(p + 6, "%x; %x; %x; %x", &next_date, &next_date_fract, &sync_state[0], &sync_state[1]);
				assert(ret == 4);
				check_sync_state = true;
			} else if (strncmp(p, "msg: ", 5) == 0 || strncmp(p, "client: ", 8) == 0 ||
						strncmp(p, "load: ", 6) == 0 || strncmp(p, "save: ", 6) == 0) {
				/* A message that is not very important to the log playback, but part of the log. */
			} else {
				/* Can't parse a line; what's wrong here? */
				DEBUG(net, 0, "trying to parse: %s", p);
				NOT_REACHED();
			}
		}
		if (f != NULL && feof(f)) {
			DEBUG(net, 0, "End of commands.log");
			fclose(f);
			f = NULL;
		}
#endif /* DEBUG_DUMP_COMMANDS */
		if (_frame_counter >= _frame_counter_max) {
			/* Only check for active clients just before we're going to send out
			 * the commands so we don't send multiple pause/unpause commands when
			 * the frame_freq is more than 1 tick. Same with distributing commands. */
			CheckPauseOnJoin();
			CheckMinActiveClients();
			NetworkDistributeCommands();
		}

		bool send_frame = false;

		/* We first increase the _frame_counter */
		_frame_counter++;
		/* Update max-frame-counter */
		if (_frame_counter > _frame_counter_max) {
			_frame_counter_max = _frame_counter + _settings_client.network.frame_freq;
			send_frame = true;
		}

		NetworkExecuteLocalCommandQueue();

		/* Then we make the frame */
		StateGameLoop();

		_sync_seed_1 = _random.state[0];
#ifdef NETWORK_SEND_DOUBLE_SEED
		_sync_seed_2 = _random.state[1];
#endif

		NetworkServer_Tick(send_frame);
	} else {
		/* Client */

		/* Make sure we are at the frame were the server is (quick-frames) */
		if (_frame_counter_server > _frame_counter) {
			while (_frame_counter_server > _frame_counter) {
				if (!ClientNetworkGameSocketHandler::GameLoop()) break;
			}
		} else {
			/* Else, keep on going till _frame_counter_max */
			if (_frame_counter_max > _frame_counter) ClientNetworkGameSocketHandler::GameLoop();
		}
	}

	NetworkSend();
}

static void NetworkGenerateServerId()
{
	Md5 checksum;
	uint8 digest[16];
	char hex_output[16 * 2 + 1];
	char coding_string[NETWORK_NAME_LENGTH];
	int di;

	snprintf(coding_string, sizeof(coding_string), "%d%s", (uint)Random(), "OpenTTD Server ID");

	/* Generate the MD5 hash */
	checksum.Append((const uint8*)coding_string, strlen(coding_string));
	checksum.Finish(digest);

	for (di = 0; di < 16; ++di) {
		sprintf(hex_output + di * 2, "%02x", digest[di]);
	}

	/* _settings_client.network.network_id is our id */
	snprintf(_settings_client.network.network_id, sizeof(_settings_client.network.network_id), "%s", hex_output);
}

void NetworkStartDebugLog(NetworkAddress address)
{
	extern SOCKET _debug_socket;  // Comes from debug.c

	DEBUG(net, 0, "Redirecting DEBUG() to %s:%d", address.GetHostname(), address.GetPort());

	SOCKET s = address.Connect();
	if (s == INVALID_SOCKET) {
		DEBUG(net, 0, "Failed to open socket for redirection DEBUG()");
		return;
	}

	_debug_socket = s;

	DEBUG(net, 0, "DEBUG() is now redirected");
}

/** This tries to launch the network for a given OS */
void NetworkStartUp()
{
	DEBUG(net, 3, "[core] starting network...");

	/* Network is available */
	_network_available = NetworkCoreInitialize();
	_network_dedicated = false;
	_network_last_advertise_frame = 0;
	_network_need_advertise = true;
	_network_advertise_retries = 0;

	/* Generate an server id when there is none yet */
	if (StrEmpty(_settings_client.network.network_id)) NetworkGenerateServerId();

	memset(&_network_game_info, 0, sizeof(_network_game_info));

	NetworkInitialize();
	DEBUG(net, 3, "[core] network online, multiplayer available");
	NetworkFindBroadcastIPs(&_broadcast_list);
}

/** This shuts the network down */
void NetworkShutDown()
{
	NetworkDisconnect(true);
	NetworkUDPClose();

	DEBUG(net, 3, "[core] shutting down network");

	_network_available = false;

	NetworkCoreShutdown();
}

/**
 * Checks whether the given version string is compatible with our version.
 * @param other the version string to compare to
 */
bool IsNetworkCompatibleVersion(const char *other)
{
	return strncmp(_openttd_revision, other, NETWORK_REVISION_LENGTH - 1) == 0;
}

#endif /* ENABLE_NETWORK */