1 /***********************************************************
2 * Rocks'n'Diamonds -- McDuffin Strikes Back! *
3 *----------------------------------------------------------*
4 * (c) 1995-2006 Artsoft Entertainment *
5 * Holger Schemel *
6 * Detmolder Strasse 189 *
7 * 33604 Bielefeld *
8 * Germany *
9 * e-mail: info@artsoft.org *
10 *----------------------------------------------------------*
11 * network.c *
12 ***********************************************************/
13
14 #include "libgame/platform.h"
15
16 #if defined(NETWORK_AVALIABLE)
17
18 #include <signal.h>
19 #include <sys/time.h>
20
21 #if defined(TARGET_SDL)
22 #include "main.h"
23 #else
24 #include <sys/wait.h>
25 #include <sys/socket.h>
26 #include <netinet/in.h>
27 #include <netinet/tcp.h>
28 #include <arpa/inet.h>
29 #include <netdb.h>
30 #endif
31
32 #include "libgame/libgame.h"
33
34 #include "network.h"
35 #include "netserv.h"
36 #include "game.h"
37 #include "tape.h"
38 #include "files.h"
39 #include "tools.h"
40 #include "screens.h"
41
42 struct NetworkClientPlayerInfo
43 {
44 byte nr;
45 char name[MAX_PLAYER_NAME_LEN + 1];
46 struct NetworkClientPlayerInfo *next;
47 };
48
49 static struct NetworkClientPlayerInfo first_player =
50 {
51 0,
52 EMPTY_PLAYER_NAME,
53 NULL
54 };
55
56 /* server stuff */
57
58 #if defined(TARGET_SDL)
59 static TCPsocket sfd; /* server socket */
60 static SDLNet_SocketSet rfds; /* socket set */
61 #else
62 static int sfd; /* server socket */
63 #endif
64
65 static byte realbuffer[512];
66 static byte readbuffer[MAX_BUFFER_SIZE], writbuffer[MAX_BUFFER_SIZE];
67 static byte *buffer = realbuffer + 4;
68 static int nread = 0, nwrite = 0;
69 static boolean stop_network_game = FALSE;
70
SendBufferToServer(int size)71 static void SendBufferToServer(int size)
72 {
73 if (!options.network)
74 return;
75
76 realbuffer[0] = realbuffer[1] = realbuffer[2] = 0;
77 realbuffer[3] = (byte)size;
78 buffer[0] = 0;
79
80 if (nwrite + 4 + size >= MAX_BUFFER_SIZE)
81 Error(ERR_EXIT, "internal error: network send buffer overflow");
82
83 memcpy(writbuffer + nwrite, realbuffer, 4 + size);
84 nwrite += 4 + size;
85
86 /* directly send the buffer to the network server */
87 #if defined(TARGET_SDL)
88 SDLNet_TCP_Send(sfd, writbuffer, nwrite);
89 #else
90 write(sfd, writbuffer, nwrite);
91 #endif
92 nwrite = 0;
93 }
94
getNetworkPlayer(int player_nr)95 struct NetworkClientPlayerInfo *getNetworkPlayer(int player_nr)
96 {
97 struct NetworkClientPlayerInfo *player = NULL;
98
99 for (player = &first_player; player; player = player->next)
100 if (player->nr == player_nr)
101 break;
102
103 if (player == NULL) /* should not happen */
104 Error(ERR_EXIT, "protocol error: reference to non-existing player %d",
105 player_nr);
106
107 return player;
108 }
109
getNetworkPlayerName(int player_nr)110 char *getNetworkPlayerName(int player_nr)
111 {
112 struct NetworkClientPlayerInfo *player;
113
114 if (player_nr == 0)
115 return("the network game server");
116 else if (player_nr == first_player.nr)
117 return("you");
118 else
119 for (player = &first_player; player; player = player->next)
120 if (player->nr == player_nr && player->name && strlen(player->name))
121 return(player->name);
122
123 return(EMPTY_PLAYER_NAME);
124 }
125
StartNetworkServer(int port)126 static void StartNetworkServer(int port)
127 {
128 #if defined(TARGET_SDL)
129 static int p;
130
131 p = port;
132 server_thread = SDL_CreateThread(NetworkServerThread, &p);
133 network_server = TRUE;
134
135 #else
136
137 switch (fork())
138 {
139 case 0:
140 NetworkServer(port, options.serveronly);
141
142 /* never reached */
143 exit(0);
144
145 case -1:
146 Error(ERR_WARN,
147 "cannot create network server process - no network playing");
148 options.network = FALSE;
149 return;
150
151 default:
152 /* we are parent process -- resume normal operation */
153 return;
154 }
155 #endif
156 }
157
158 #if defined(TARGET_SDL)
ConnectToServer(char * hostname,int port)159 boolean ConnectToServer(char *hostname, int port)
160 {
161 IPaddress ip;
162 int i;
163
164 if (port == 0)
165 port = DEFAULT_SERVER_PORT;
166
167 rfds = SDLNet_AllocSocketSet(1);
168
169 if (hostname)
170 {
171 SDLNet_ResolveHost(&ip, hostname, port);
172 if (ip.host == INADDR_NONE)
173 Error(ERR_EXIT, "cannot locate host '%s'", hostname);
174 }
175 else
176 {
177 SDLNet_Write32(0x7f000001, &ip.host); /* 127.0.0.1 */
178 SDLNet_Write16(port, &ip.port);
179 }
180
181 sfd = SDLNet_TCP_Open(&ip);
182
183 if (sfd)
184 {
185 SDLNet_TCP_AddSocket(rfds, sfd);
186 return TRUE;
187 }
188 else
189 {
190 printf("SDLNet_TCP_Open(): %s\n", SDLNet_GetError());
191 }
192
193 if (hostname) /* connect to specified server failed */
194 return FALSE;
195
196 printf("No rocksndiamonds server on localhost -- starting up one ...\n");
197 StartNetworkServer(port);
198
199 /* wait for server to start up and try connecting several times */
200 for (i = 0; i < 6; i++)
201 {
202 Delay(500); /* wait 500 ms == 0.5 seconds */
203
204 if ((sfd = SDLNet_TCP_Open(&ip))) /* connected */
205 {
206 SDLNet_TCP_AddSocket(rfds, sfd);
207 return TRUE;
208 }
209 }
210
211 /* when reaching this point, connect to newly started server has failed */
212 return FALSE;
213 }
214
215 #else
216
ConnectToServer(char * hostname,int port)217 boolean ConnectToServer(char *hostname, int port)
218 {
219 struct sockaddr_in s;
220 struct protoent *tcpproto;
221 int on = 1, i;
222
223 if (hostname)
224 {
225 if ((s.sin_addr.s_addr = inet_addr(hostname)) == -1)
226 {
227 struct hostent *host;
228
229 if ((host = gethostbyname(hostname)) == NULL)
230 Error(ERR_EXIT, "cannot locate host '%s'", hostname);
231
232 s.sin_addr = *(struct in_addr *)(host->h_addr_list[0]);
233 }
234 }
235 else
236 s.sin_addr.s_addr = inet_addr("127.0.0.1"); /* localhost */
237
238 if (port == 0)
239 port = DEFAULT_SERVER_PORT;
240
241 s.sin_port = htons(port);
242 s.sin_family = AF_INET;
243
244 sfd = socket(PF_INET, SOCK_STREAM, 0);
245 if (sfd < 0)
246 Error(ERR_EXIT, "out of file descriptors");
247
248 if ((tcpproto = getprotobyname("tcp")) != NULL)
249 setsockopt(sfd, tcpproto->p_proto, TCP_NODELAY, (char *)&on, sizeof(int));
250
251 if (connect(sfd, (struct sockaddr *)&s, sizeof(s)) == 0) /* connected */
252 return TRUE;
253
254 if (hostname) /* connect to specified server failed */
255 return FALSE;
256
257 printf("No rocksndiamonds server on localhost -- starting up one ...\n");
258 StartNetworkServer(port);
259
260 /* wait for server to start up and try connecting several times */
261 for (i = 0; i < 6; i++)
262 {
263 Delay(500); /* wait 500 ms == 0.5 seconds */
264 close(sfd);
265
266 sfd = socket(PF_INET, SOCK_STREAM, 0);
267 if (sfd < 0)
268 Error(ERR_EXIT, "out of file descriptors");
269
270 setsockopt(sfd, tcpproto->p_proto, TCP_NODELAY, (char *)&on, sizeof(int));
271
272 if (connect(sfd, (struct sockaddr *)&s, sizeof(s)) >= 0) /* connected */
273 return TRUE;
274 }
275
276 /* when reaching this point, connect to newly started server has failed */
277 return FALSE;
278 }
279 #endif /* defined(TARGET_SDL) */
280
SendToServer_PlayerName(char * player_name)281 void SendToServer_PlayerName(char *player_name)
282 {
283 int len_player_name = strlen(player_name);
284
285 buffer[1] = OP_PLAYER_NAME;
286 memcpy(&buffer[2], player_name, len_player_name);
287 SendBufferToServer(2 + len_player_name);
288 Error(ERR_NETWORK_CLIENT, "you set your player name to \"%s\"", player_name);
289 }
290
SendToServer_ProtocolVersion()291 void SendToServer_ProtocolVersion()
292 {
293 buffer[1] = OP_PROTOCOL_VERSION;
294 buffer[2] = PROTOCOL_VERSION_1;
295 buffer[3] = PROTOCOL_VERSION_2;
296 buffer[4] = PROTOCOL_VERSION_3;
297
298 SendBufferToServer(5);
299 }
300
SendToServer_NrWanted(int nr_wanted)301 void SendToServer_NrWanted(int nr_wanted)
302 {
303 buffer[1] = OP_NUMBER_WANTED;
304 buffer[2] = nr_wanted;
305
306 SendBufferToServer(3);
307 }
308
SendToServer_StartPlaying()309 void SendToServer_StartPlaying()
310 {
311 unsigned long new_random_seed = InitRND(level.random_seed);
312
313 int dummy = 0; /* !!! HAS NO MEANING ANYMORE !!! */
314 /* the name of the level must be enough */
315
316 buffer[1] = OP_START_PLAYING;
317 buffer[2] = (byte)(level_nr >> 8);
318 buffer[3] = (byte)(level_nr & 0xff);
319 buffer[4] = (byte)(dummy >> 8);
320 buffer[5] = (byte)(dummy & 0xff);
321
322 buffer[6] = (unsigned char)((new_random_seed >> 24) & 0xff);
323 buffer[7] = (unsigned char)((new_random_seed >> 16) & 0xff);
324 buffer[8] = (unsigned char)((new_random_seed >> 8) & 0xff);
325 buffer[9] = (unsigned char)((new_random_seed >> 0) & 0xff);
326
327 strcpy((char *)&buffer[10], leveldir_current->identifier);
328
329 SendBufferToServer(10 + strlen(leveldir_current->identifier) + 1);
330 }
331
SendToServer_PausePlaying()332 void SendToServer_PausePlaying()
333 {
334 buffer[1] = OP_PAUSE_PLAYING;
335
336 SendBufferToServer(2);
337 }
338
SendToServer_ContinuePlaying()339 void SendToServer_ContinuePlaying()
340 {
341 buffer[1] = OP_CONTINUE_PLAYING;
342
343 SendBufferToServer(2);
344 }
345
SendToServer_StopPlaying(int cause_for_stopping)346 void SendToServer_StopPlaying(int cause_for_stopping)
347 {
348 buffer[1] = OP_STOP_PLAYING;
349 buffer[2] = cause_for_stopping;
350
351 SendBufferToServer(3);
352 }
353
SendToServer_MovePlayer(byte player_action)354 void SendToServer_MovePlayer(byte player_action)
355 {
356 buffer[1] = OP_MOVE_PLAYER;
357 buffer[2] = player_action;
358
359 SendBufferToServer(3);
360 }
361
Handle_OP_BAD_PROTOCOL_VERSION()362 static void Handle_OP_BAD_PROTOCOL_VERSION()
363 {
364 Error(ERR_WARN, "protocol version mismatch");
365 Error(ERR_EXIT, "server expects %d.%d.x instead of %d.%d.%d",
366 buffer[2], buffer[3],
367 PROTOCOL_VERSION_1, PROTOCOL_VERSION_2, PROTOCOL_VERSION_3);
368 }
369
Handle_OP_YOUR_NUMBER()370 static void Handle_OP_YOUR_NUMBER()
371 {
372 int new_client_nr = buffer[2];
373 int new_index_nr = new_client_nr - 1;
374 struct PlayerInfo *old_local_player = local_player;
375 struct PlayerInfo *new_local_player = &stored_player[new_index_nr];
376
377 printf("OP_YOUR_NUMBER: %d\n", buffer[0]);
378 first_player.nr = new_client_nr;
379
380 if (old_local_player != new_local_player)
381 {
382 /* copy existing player settings and change to new player */
383
384 *new_local_player = *old_local_player;
385 old_local_player->connected = FALSE;
386 local_player = new_local_player;
387 }
388
389 if (first_player.nr > MAX_PLAYERS)
390 Error(ERR_EXIT, "sorry, more than %d players not allowed", MAX_PLAYERS);
391
392 Error(ERR_NETWORK_CLIENT, "you get client # %d", new_client_nr);
393 }
394
Handle_OP_NUMBER_WANTED()395 static void Handle_OP_NUMBER_WANTED()
396 {
397 int client_nr_wanted = buffer[2];
398 int old_client_nr = buffer[0];
399 int new_client_nr = buffer[3];
400 int old_index_nr = old_client_nr - 1;
401 int new_index_nr = new_client_nr - 1;
402 int index_nr_wanted = client_nr_wanted - 1;
403 struct PlayerInfo *old_player = &stored_player[old_index_nr];
404 struct PlayerInfo *new_player = &stored_player[new_index_nr];
405
406 printf("OP_NUMBER_WANTED: %d\n", buffer[0]);
407
408 if (new_client_nr == client_nr_wanted) /* switching succeeded */
409 {
410 struct NetworkClientPlayerInfo *player;
411
412 if (old_client_nr != client_nr_wanted) /* client's nr has changed */
413 Error(ERR_NETWORK_CLIENT, "client %d switches to # %d",
414 old_client_nr, new_client_nr);
415 else if (old_client_nr == first_player.nr) /* local player keeps his nr */
416 Error(ERR_NETWORK_CLIENT, "keeping client # %d", new_client_nr);
417
418 if (old_client_nr != new_client_nr)
419 {
420 /* copy existing player settings and change to new player */
421
422 *new_player = *old_player;
423 old_player->connected = FALSE;
424 }
425
426 player = getNetworkPlayer(old_client_nr);
427 player->nr = new_client_nr;
428
429 if (old_player == local_player) /* local player switched */
430 local_player = new_player;
431 }
432 else if (old_client_nr == first_player.nr) /* failed -- local player? */
433 {
434 char request[100];
435
436 sprintf(request, "Sorry ! Player %d already exists ! You are player %d !",
437 index_nr_wanted + 1, new_index_nr + 1);
438
439 Request(request, REQ_CONFIRM);
440
441 Error(ERR_NETWORK_CLIENT, "cannot switch -- you keep client # %d",
442 new_client_nr);
443 }
444 }
445
Handle_OP_PLAYER_NAME(unsigned int len)446 static void Handle_OP_PLAYER_NAME(unsigned int len)
447 {
448 struct NetworkClientPlayerInfo *player;
449 int player_nr = (int)buffer[0];
450
451 printf("OP_PLAYER_NAME: %d\n", player_nr);
452 player = getNetworkPlayer(player_nr);
453 buffer[len] = 0;
454 Error(ERR_NETWORK_CLIENT, "client %d calls itself \"%s\"",
455 buffer[0], &buffer[2]);
456 strncpy(player->name, (char *)&buffer[2], MAX_PLAYER_NAME_LEN);
457 }
458
Handle_OP_PLAYER_CONNECTED()459 static void Handle_OP_PLAYER_CONNECTED()
460 {
461 struct NetworkClientPlayerInfo *player, *last_player = NULL;
462 int new_client_nr = (int)buffer[0];
463 int new_index_nr = new_client_nr - 1;
464
465 printf("OP_PLAYER_CONNECTED: %d\n", new_client_nr);
466 Error(ERR_NETWORK_CLIENT, "new client %d connected", new_client_nr);
467
468 for (player = &first_player; player; player = player->next)
469 {
470 if (player->nr == new_client_nr)
471 Error(ERR_EXIT, "multiplayer server sent duplicate player id");
472
473 last_player = player;
474 }
475
476 last_player->next = player =
477 checked_malloc(sizeof(struct NetworkClientPlayerInfo));
478 player->nr = new_client_nr;
479 player->name[0] = '\0';
480 player->next = NULL;
481
482 stored_player[new_index_nr].connected = TRUE;
483 }
484
Handle_OP_PLAYER_DISCONNECTED()485 static void Handle_OP_PLAYER_DISCONNECTED()
486 {
487 struct NetworkClientPlayerInfo *player, *player_disconnected;
488 int player_nr = (int)buffer[0];
489
490 printf("OP_PLAYER_DISCONNECTED: %d\n", player_nr);
491 player_disconnected = getNetworkPlayer(player_nr);
492 Error(ERR_NETWORK_CLIENT, "client %d (%s) disconnected",
493 player_nr, getNetworkPlayerName(buffer[0]));
494
495 for (player = &first_player; player; player = player->next)
496 if (player->next == player_disconnected)
497 player->next = player_disconnected->next;
498 free(player_disconnected);
499 }
500
Handle_OP_START_PLAYING()501 static void Handle_OP_START_PLAYING()
502 {
503 LevelDirTree *new_leveldir;
504 int new_level_nr;
505 int dummy;
506 unsigned long new_random_seed;
507 char *new_leveldir_identifier;
508
509 new_level_nr = (buffer[2] << 8) + buffer[3];
510 dummy = (buffer[4] << 8) + buffer[5]; /* (obsolete) */
511 new_random_seed =
512 (buffer[6] << 24) | (buffer[7] << 16) | (buffer[8] << 8) | (buffer[9]);
513 new_leveldir_identifier = (char *)&buffer[10];
514
515 new_leveldir = getTreeInfoFromIdentifier(leveldir_first,
516 new_leveldir_identifier);
517 if (new_leveldir == NULL)
518 {
519 Error(ERR_WARN, "no such level identifier: '%s'", new_leveldir_identifier);
520
521 new_leveldir = leveldir_first;
522 Error(ERR_WARN, "using default level set: '%s'", new_leveldir->identifier);
523 }
524
525 printf("OP_START_PLAYING: %d\n", buffer[0]);
526 Error(ERR_NETWORK_CLIENT,
527 "client %d starts game [level %d from level identifier '%s']\n",
528 buffer[0], new_level_nr, new_leveldir->identifier);
529
530 leveldir_current = new_leveldir;
531 level_nr = new_level_nr;
532
533 TapeErase();
534 LoadTape(level_nr);
535 LoadLevel(level_nr);
536
537 StartGameActions(FALSE, setup.autorecord, new_random_seed);
538 }
539
Handle_OP_PAUSE_PLAYING()540 static void Handle_OP_PAUSE_PLAYING()
541 {
542 printf("OP_PAUSE_PLAYING: %d\n", buffer[0]);
543 Error(ERR_NETWORK_CLIENT, "client %d pauses game", buffer[0]);
544
545 tape.pausing = TRUE;
546 DrawVideoDisplay(VIDEO_STATE_PAUSE_ON,0);
547 }
548
Handle_OP_CONTINUE_PLAYING()549 static void Handle_OP_CONTINUE_PLAYING()
550 {
551 printf("OP_CONTINUE_PLAYING: %d\n", buffer[0]);
552 Error(ERR_NETWORK_CLIENT, "client %d continues game", buffer[0]);
553
554 tape.pausing = FALSE;
555 DrawVideoDisplay(VIDEO_STATE_PAUSE_OFF,0);
556 }
557
Handle_OP_STOP_PLAYING()558 static void Handle_OP_STOP_PLAYING()
559 {
560 printf("OP_STOP_PLAYING: %d [%d]\n", buffer[0], buffer[2]);
561 Error(ERR_NETWORK_CLIENT, "client %d stops game [%d]", buffer[0], buffer[2]);
562
563 if (game_status == GAME_MODE_PLAYING)
564 {
565 if (buffer[2] == NETWORK_STOP_BY_PLAYER)
566 Request("Network game stopped by player!", REQ_CONFIRM);
567 else if (buffer[2] == NETWORK_STOP_BY_ERROR)
568 Request("Network game stopped due to internal error!", REQ_CONFIRM);
569 else
570 Request("Network game stopped !", REQ_CONFIRM);
571 }
572
573 game_status = GAME_MODE_MAIN;
574 DrawMainMenu();
575 }
576
Handle_OP_MOVE_PLAYER(unsigned int len)577 static void Handle_OP_MOVE_PLAYER(unsigned int len)
578 {
579 int server_frame_counter;
580 int i;
581
582 if (!network_playing)
583 return;
584
585 server_frame_counter =
586 (buffer[2] << 24) | (buffer[3] << 16) | (buffer[4] << 8) | (buffer[5]);
587
588 #if 0
589 Error(ERR_NETWORK_CLIENT, "receiving server frame counter value %d [%d]",
590 server_frame_counter, FrameCounter);
591 #endif
592
593 if (server_frame_counter != FrameCounter)
594 {
595 Error(ERR_INFO, "client and servers frame counters out of sync");
596 Error(ERR_INFO, "frame counter of client is %d", FrameCounter);
597 Error(ERR_INFO, "frame counter of server is %d", server_frame_counter);
598 Error(ERR_INFO, "this should not happen -- please debug");
599
600 stop_network_game = TRUE;
601
602 return;
603 }
604
605 /* copy valid player actions */
606 for (i = 0; i < MAX_PLAYERS; i++)
607 stored_player[i].effective_action =
608 (i < len - 6 && stored_player[i].active ? buffer[6 + i] : 0);
609
610 network_player_action_received = TRUE;
611 }
612
HandleNetworkingMessages()613 static void HandleNetworkingMessages()
614 {
615 unsigned int message_length;
616
617 stop_network_game = FALSE;
618
619 while (nread >= 4 && nread >= 4 + readbuffer[3])
620 {
621 message_length = readbuffer[3];
622 if (readbuffer[0] || readbuffer[1] || readbuffer[2])
623 Error(ERR_EXIT, "wrong network server line length");
624
625 memcpy(buffer, &readbuffer[4], message_length);
626 nread -= 4 + message_length;
627 memmove(readbuffer, readbuffer + 4 + message_length, nread);
628
629 switch (buffer[1])
630 {
631 case OP_BAD_PROTOCOL_VERSION:
632 Handle_OP_BAD_PROTOCOL_VERSION();
633 break;
634
635 case OP_YOUR_NUMBER:
636 Handle_OP_YOUR_NUMBER();
637 break;
638
639 case OP_NUMBER_WANTED:
640 Handle_OP_NUMBER_WANTED();
641 break;
642
643 case OP_PLAYER_NAME:
644 Handle_OP_PLAYER_NAME(message_length);
645 break;
646
647 case OP_PLAYER_CONNECTED:
648 Handle_OP_PLAYER_CONNECTED();
649 break;
650
651 case OP_PLAYER_DISCONNECTED:
652 Handle_OP_PLAYER_DISCONNECTED();
653 break;
654
655 case OP_START_PLAYING:
656 Handle_OP_START_PLAYING();
657 break;
658
659 case OP_PAUSE_PLAYING:
660 Handle_OP_PAUSE_PLAYING();
661 break;
662
663 case OP_CONTINUE_PLAYING:
664 Handle_OP_CONTINUE_PLAYING();
665 break;
666
667 case OP_STOP_PLAYING:
668 Handle_OP_STOP_PLAYING();
669 break;
670
671 case OP_MOVE_PLAYER:
672 Handle_OP_MOVE_PLAYER(message_length);
673 break;
674
675 case OP_BROADCAST_MESSAGE:
676 printf("OP_BROADCAST_MESSAGE: %d\n", buffer[0]);
677 Error(ERR_NETWORK_CLIENT, "client %d sends message", buffer[0]);
678 break;
679 }
680 }
681
682 fflush(stdout);
683
684 /* in case of internal error, stop network game */
685 if (stop_network_game)
686 SendToServer_StopPlaying(NETWORK_STOP_BY_ERROR);
687 }
688
689 /* TODO */
690
HandleNetworking()691 void HandleNetworking()
692 {
693 #if !defined(TARGET_SDL)
694 static struct timeval tv = { 0, 0 };
695 fd_set rfds;
696 #endif
697 int r = 0;
698
699 do
700 {
701 #if defined(TARGET_SDL)
702 if ((r = SDLNet_CheckSockets(rfds, 1)) < 0)
703 Error(ERR_EXIT, "HandleNetworking(): SDLNet_CheckSockets() failed");
704
705 #else
706
707 FD_ZERO(&rfds);
708 FD_SET(sfd, &rfds);
709
710 r = select(sfd + 1, &rfds, NULL, NULL, &tv);
711
712 if (r < 0 && errno != EINTR)
713 Error(ERR_EXIT, "HandleNetworking(): select() failed");
714
715 if (r < 0)
716 FD_ZERO(&rfds);
717 #endif
718
719 #if defined(TARGET_SDL)
720 if (r > 0)
721 #else
722 if (FD_ISSET(sfd, &rfds))
723 #endif
724 {
725 #if defined(TARGET_SDL)
726 r = SDLNet_TCP_Recv(sfd, readbuffer + nread, 1);
727 #else
728 r = read(sfd, readbuffer + nread, MAX_BUFFER_SIZE - nread);
729 #endif
730
731 if (r < 0)
732 Error(ERR_EXIT, "error reading from network server");
733
734 if (r == 0)
735 Error(ERR_EXIT, "connection to network server lost");
736
737 nread += r;
738
739 HandleNetworkingMessages();
740 }
741 }
742 while (r > 0);
743 }
744
745 #endif /* PLATFORM_UNIX */
746