src/network.c

   1 // ============================================================================
   2 // Rocks'n'Diamonds - McDuffin Strikes Back!
   3 // ----------------------------------------------------------------------------
   4 // (c) 1995-2014 by Artsoft Entertainment
   5 //                  Holger Schemel
   6 //                  info@artsoft.org
   7 //                  http://www.artsoft.org/
   8 // ----------------------------------------------------------------------------
   9 // network.c
  10 // ============================================================================
  11
  12 #include <signal.h>
  13 #include <sys/time.h>
  14
  15 #include "libgame/libgame.h"
  16
  17 #include "network.h"
  18 #include "netserv.h"
  19 #include "main.h"
  20 #include "game.h"
  21 #include "tape.h"
  22 #include "files.h"
  23 #include "tools.h"
  24 #include "screens.h"
  25
  26 struct NetworkClientPlayerInfo
  27 {
  28   byte nr;
  29   char name[MAX_PLAYER_NAME_LEN + 1];
  30   struct NetworkClientPlayerInfo *next;
  31 };
  32
  33 static struct NetworkClientPlayerInfo first_player =
  34 {
  35   0,
  36   EMPTY_PLAYER_NAME,
  37   NULL
  38 };
  39
  40 /* server stuff */
  41
  42 static TCPsocket sfd;           /* TCP server socket */
  43 static UDPsocket udp;           /* UDP server socket */
  44 static SDLNet_SocketSet rfds;   /* socket set */
  45
  46 static struct NetworkBuffer *read_buffer = NULL;
  47 static struct NetworkBuffer *write_buffer = NULL;
  48
  49 static boolean stop_network_game = FALSE;
  50 static boolean stop_network_client = FALSE;
  51 static char stop_network_client_message[MAX_OUTPUT_LINESIZE + 1];
  52
  53 static void DrawNetworkTextExt(char *message, int font_nr, boolean initialize)
  54 {
  55   static int xpos = 0, ypos = 0;
  56   static int max_line_width = 0;
  57   int font_width = getFontWidth(font_nr);
  58   int font_height = getFontHeight(font_nr);
  59   int ypos_1 = 120;
  60   int ypos_2 = 150;
  61
  62   if (initialize)
  63   {
  64     if (game_status == GAME_MODE_LOADING)
  65     {
  66       max_line_width = WIN_XSIZE;
  67
  68       xpos = (max_line_width - getTextWidth(message, font_nr)) / 2;
  69       ypos = ypos_1;
  70
  71       DrawText(xpos, ypos, message, font_nr);
  72
  73       xpos = 0;
  74       ypos = ypos_2;
  75     }
  76     else
  77     {
  78       max_line_width = SXSIZE;
  79
  80       DrawTextSCentered(ypos_1, font_nr, message);
  81
  82       /* calculate offset to x position caused by rounding */
  83       int max_chars_per_line = max_line_width / font_width;
  84       int xoffset = (max_line_width - max_chars_per_line * font_width) / 2;
  85
  86       xpos = SX + xoffset;
  87       ypos = SY + ypos_2;
  88     }
  89
  90     Error(ERR_DEBUG, "========== %s ==========", message);
  91   }
  92   else
  93   {
  94     int max_chars_per_line = max_line_width / font_width;
  95     int max_lines_per_text = 10;
  96     int num_lines_spacing = (font_nr == FC_YELLOW ? 1 : 3);
  97     int num_lines_printed = DrawTextBuffer(xpos, ypos, message, font_nr,
  98                                            max_chars_per_line, -1,
  99                                            max_lines_per_text, 0, -1,
 100                                            TRUE, TRUE, FALSE);
 101
 102     ypos += (num_lines_printed + num_lines_spacing) * font_height;
 103
 104     Error(ERR_DEBUG, "%s", message);
 105   }
 106
 107   BackToFront();
 108 }
 109
 110 static void DrawNetworkText(char *message)
 111 {
 112   DrawNetworkTextExt(message, FC_YELLOW, FALSE);
 113 }
 114
 115 static void DrawNetworkText_Success(char *message)
 116 {
 117   DrawNetworkTextExt(message, FC_GREEN, FALSE);
 118 }
 119
 120 static void DrawNetworkText_Failed(char *message)
 121 {
 122   DrawNetworkTextExt(message, FC_RED, FALSE);
 123 }
 124
 125 static void DrawNetworkText_Title(char *message)
 126 {
 127   DrawNetworkTextExt(message, FC_GREEN, TRUE);
 128 }
 129
 130 static void SendNetworkBufferToServer(struct NetworkBuffer *nb)
 131 {
 132   if (!network.enabled)
 133     return;
 134
 135   /* set message length header */
 136   putNetwork32BitInteger(nb->buffer, nb->size - 4);
 137
 138   /* directly send the buffer to the network server */
 139   SDLNet_TCP_Send(sfd, nb->buffer, nb->size);
 140 }
 141
 142 struct NetworkClientPlayerInfo *getNetworkPlayer(int player_nr)
 143 {
 144   struct NetworkClientPlayerInfo *player = NULL;
 145
 146   for (player = &first_player; player; player = player->next)
 147     if (player->nr == player_nr)
 148       break;
 149
 150   if (player == NULL)   /* should not happen */
 151     Error(ERR_EXIT, "protocol error: reference to non-existing player %d",
 152           player_nr);
 153
 154   return player;
 155 }
 156
 157 char *getNetworkPlayerName(int player_nr)
 158 {
 159   struct NetworkClientPlayerInfo *player;
 160
 161   if (player_nr == 0)
 162     return("the network game server");
 163   else if (player_nr == first_player.nr)
 164     return("you");
 165   else
 166     for (player = &first_player; player; player = player->next)
 167       if (player->nr == player_nr && strlen(player->name) > 0)
 168         return(player->name);
 169
 170   return(EMPTY_PLAYER_NAME);
 171 }
 172
 173 static void StartNetworkServer(int port)
 174 {
 175   static int p;
 176
 177   p = port;
 178 #if defined(TARGET_SDL2)
 179   server_thread = SDL_CreateThread(NetworkServerThread,
 180                                    "NetworkServerThread", &p);
 181 #else
 182   server_thread = SDL_CreateThread(NetworkServerThread, &p);
 183 #endif
 184   network_server = TRUE;
 185 }
 186
 187 boolean ConnectToServer(char *hostname, int port)
 188 {
 189   IPaddress ip;
 190   int server_host = 0;
 191   int i;
 192
 193   if (read_buffer == NULL)
 194     read_buffer = newNetworkBuffer();
 195
 196   if (write_buffer == NULL)
 197     write_buffer = newNetworkBuffer();
 198
 199   DrawNetworkText_Title("Initializing Network");
 200
 201   if (port == 0)
 202     port = DEFAULT_SERVER_PORT;
 203
 204   if (hostname == NULL)
 205   {
 206     // if no hostname given, try to auto-detect network server in local network
 207     // by doing a UDP broadcast on the network server port and wait for answer
 208
 209     SDLNet_SocketSet udp_socket_set = SDLNet_AllocSocketSet(1);
 210     if (!udp_socket_set)
 211       Error(ERR_EXIT, "SDLNet_AllocSocketSet() failed: %s"), SDLNet_GetError();
 212
 213     udp = SDLNet_UDP_Open(0);
 214     if(!udp)
 215       Error(ERR_EXIT, "SDLNet_UDP_Open() failed: %s", SDLNet_GetError());
 216
 217     if (SDLNet_UDP_AddSocket(udp_socket_set, udp) == -1)
 218       Error(ERR_EXIT_NETWORK_SERVER, "SDLNet_TCP_AddSocket() failed: %s"),
 219         SDLNet_GetError();
 220
 221     char *data_ptr = "network server UDB broadcast";
 222     int data_len = strlen(data_ptr) + 1;
 223     IPaddress ip_address;
 224
 225     SDLNet_Write32(0xffffffff, &ip_address.host);       /* 255.255.255.255 */
 226     SDLNet_Write16(port,       &ip_address.port);
 227
 228     UDPpacket packet =
 229     {
 230       -1,
 231       (Uint8 *)data_ptr,
 232       data_len,
 233       data_len,
 234       0,
 235       ip_address
 236     };
 237
 238     SDLNet_UDP_Send(udp, -1, &packet);
 239
 240     DrawNetworkText("Looking for local network server ...");
 241
 242     /* wait for any local network server to answer UDP broadcast */
 243     for (i = 0; i < 5; i++)
 244     {
 245       if (SDLNet_CheckSockets(udp_socket_set, 0) == 1)
 246       {
 247         int num_packets = SDLNet_UDP_Recv(udp, &packet);
 248
 249         if (num_packets == 1)
 250         {
 251           DrawNetworkText_Success("Network server found!");
 252
 253           server_host = SDLNet_Read32(&packet.address.host);
 254         }
 255         else
 256         {
 257           DrawNetworkText_Failed("No answer from network server!");
 258         }
 259
 260         break;
 261       }
 262       else
 263       {
 264         Delay_WithScreenUpdates(100);
 265       }
 266     }
 267
 268     if (server_host == 0)
 269       DrawNetworkText_Failed("No network server found!");
 270   }
 271
 272   rfds = SDLNet_AllocSocketSet(1);
 273
 274   if (hostname)
 275   {
 276     SDLNet_ResolveHost(&ip, hostname, port);
 277
 278     if (ip.host == INADDR_NONE)
 279       Error(ERR_EXIT, "cannot locate host '%s'", hostname);
 280     else
 281       server_host = SDLNet_Read32(&ip.host);
 282
 283     DrawNetworkText("Connecting to remote host ...");
 284   }
 285   else
 286   {
 287     // if no hostname was given and no network server was auto-detected in the
 288     // local network, try to connect to a network server at the local host
 289     if (server_host == 0)
 290       server_host = 0x7f000001;                 /* 127.0.0.1 */
 291
 292     SDLNet_Write32(server_host, &ip.host);
 293     SDLNet_Write16(port,        &ip.port);
 294
 295     DrawNetworkText("Connecting to local host ...");
 296   }
 297
 298   Error(ERR_DEBUG, "trying to connect to network server at %d.%d.%d.%d ...",
 299         (server_host >> 24) & 0xff,
 300         (server_host >> 16) & 0xff,
 301         (server_host >>  8) & 0xff,
 302         (server_host >>  0) & 0xff);
 303
 304   sfd = SDLNet_TCP_Open(&ip);
 305
 306   if (sfd)
 307   {
 308     SDLNet_TCP_AddSocket(rfds, sfd);
 309
 310     DrawNetworkText_Success("Successfully connected!");
 311
 312     return TRUE;
 313   }
 314   else
 315   {
 316     DrawNetworkText_Failed("Failed to connect to network server!");
 317
 318     printf("SDLNet_TCP_Open(): %s\n", SDLNet_GetError());
 319   }
 320
 321   if (hostname)                 /* connect to specified server failed */
 322     return FALSE;
 323
 324   DrawNetworkText("Starting new local network server ...");
 325
 326   StartNetworkServer(port);
 327
 328   /* wait for server to start up and try connecting several times */
 329   for (i = 0; i < 30; i++)
 330   {
 331     if ((sfd = SDLNet_TCP_Open(&ip)))           /* connected */
 332     {
 333       DrawNetworkText_Success("Successfully connected!");
 334
 335       SDLNet_TCP_AddSocket(rfds, sfd);
 336       return TRUE;
 337     }
 338
 339     Delay_WithScreenUpdates(100);
 340   }
 341
 342   DrawNetworkText_Failed("Failed to connect to network server!");
 343
 344   /* when reaching this point, connect to newly started server has failed */
 345   return FALSE;
 346 }
 347
 348 void SendToServer_PlayerName(char *player_name)
 349 {
 350   initNetworkBufferForWriting(write_buffer, OP_PLAYER_NAME, 0);
 351
 352   putNetworkBufferString(write_buffer, player_name);
 353
 354   SendNetworkBufferToServer(write_buffer);
 355
 356   Error(ERR_NETWORK_CLIENT, "you set your player name to \"%s\"", player_name);
 357 }
 358
 359 void SendToServer_ProtocolVersion()
 360 {
 361   initNetworkBufferForWriting(write_buffer, OP_PROTOCOL_VERSION, 0);
 362
 363   putNetworkBuffer8BitInteger(write_buffer, PROTOCOL_VERSION_MAJOR);
 364   putNetworkBuffer8BitInteger(write_buffer, PROTOCOL_VERSION_MINOR);
 365   putNetworkBuffer8BitInteger(write_buffer, PROTOCOL_VERSION_PATCH);
 366
 367   SendNetworkBufferToServer(write_buffer);
 368 }
 369
 370 void SendToServer_NrWanted(int nr_wanted)
 371 {
 372   initNetworkBufferForWriting(write_buffer, OP_NUMBER_WANTED, 0);
 373
 374   putNetworkBuffer8BitInteger(write_buffer, nr_wanted);
 375
 376   SendNetworkBufferToServer(write_buffer);
 377 }
 378
 379 void SendToServer_StartPlaying()
 380 {
 381   unsigned int new_random_seed = InitRND(level.random_seed);
 382
 383   initNetworkBufferForWriting(write_buffer, OP_START_PLAYING, 0);
 384
 385   putNetworkBufferString(      write_buffer, leveldir_current->identifier);
 386   putNetworkBuffer16BitInteger(write_buffer, level_nr);
 387   putNetworkBuffer32BitInteger(write_buffer, new_random_seed);
 388
 389   SendNetworkBufferToServer(write_buffer);
 390 }
 391
 392 void SendToServer_PausePlaying()
 393 {
 394   initNetworkBufferForWriting(write_buffer, OP_PAUSE_PLAYING, 0);
 395
 396   SendNetworkBufferToServer(write_buffer);
 397 }
 398
 399 void SendToServer_ContinuePlaying()
 400 {
 401   initNetworkBufferForWriting(write_buffer, OP_CONTINUE_PLAYING, 0);
 402
 403   SendNetworkBufferToServer(write_buffer);
 404 }
 405
 406 void SendToServer_StopPlaying(int cause_for_stopping)
 407 {
 408   initNetworkBufferForWriting(write_buffer, OP_STOP_PLAYING, 0);
 409
 410   putNetworkBuffer8BitInteger(write_buffer, cause_for_stopping);
 411
 412   SendNetworkBufferToServer(write_buffer);
 413 }
 414
 415 void SendToServer_MovePlayer(byte player_action)
 416 {
 417   initNetworkBufferForWriting(write_buffer, OP_MOVE_PLAYER, 0);
 418
 419   putNetworkBuffer8BitInteger(write_buffer, player_action);
 420
 421   SendNetworkBufferToServer(write_buffer);
 422 }
 423
 424 static void Handle_OP_BAD_PROTOCOL_VERSION()
 425 {
 426   int protocol_version_major = getNetworkBuffer8BitInteger(read_buffer);
 427   int protocol_version_minor = getNetworkBuffer8BitInteger(read_buffer);
 428
 429   Error(ERR_WARN, "protocol version mismatch");
 430   Error(ERR_WARN, "server expects %d.%d.x instead of %d.%d.%d",
 431         protocol_version_major,
 432         protocol_version_minor,
 433         PROTOCOL_VERSION_MAJOR,
 434         PROTOCOL_VERSION_MINOR,
 435         PROTOCOL_VERSION_PATCH);
 436
 437   sprintf(stop_network_client_message, "Network protocol version mismatch! Server expects version %d.%d.x instead of %d.%d.%d!",
 438           protocol_version_major,
 439           protocol_version_minor,
 440           PROTOCOL_VERSION_MAJOR,
 441           PROTOCOL_VERSION_MINOR,
 442           PROTOCOL_VERSION_PATCH);
 443
 444   stop_network_client = TRUE;
 445 }
 446
 447 static void Handle_OP_YOUR_NUMBER()
 448 {
 449   int old_client_nr = getNetworkBuffer8BitInteger(read_buffer);
 450   int new_client_nr = getNetworkBuffer8BitInteger(read_buffer);
 451   int new_index_nr = new_client_nr - 1;
 452   struct PlayerInfo *old_local_player = local_player;
 453   struct PlayerInfo *new_local_player = &stored_player[new_index_nr];
 454
 455   printf("OP_YOUR_NUMBER: %d\n", old_client_nr);
 456   first_player.nr = new_client_nr;
 457
 458   if (old_local_player != new_local_player)
 459   {
 460     /* set relevant player settings and change to new player */
 461
 462     local_player = new_local_player;
 463
 464     old_local_player->connected_locally = FALSE;
 465     new_local_player->connected_locally = TRUE;
 466
 467     old_local_player->connected_network = FALSE;
 468     new_local_player->connected_network = TRUE;
 469   }
 470
 471   if (first_player.nr > MAX_PLAYERS)
 472     Error(ERR_EXIT, "sorry, more than %d players not allowed", MAX_PLAYERS);
 473
 474   Error(ERR_NETWORK_CLIENT, "you get client # %d", new_client_nr);
 475
 476   stored_player[new_index_nr].connected_network = TRUE;
 477 }
 478
 479 static void Handle_OP_NUMBER_WANTED()
 480 {
 481   int old_client_nr    = getNetworkBuffer8BitInteger(read_buffer);
 482   int client_nr_wanted = getNetworkBuffer8BitInteger(read_buffer);
 483   int new_client_nr    = getNetworkBuffer8BitInteger(read_buffer);
 484   int old_index_nr = old_client_nr - 1;
 485   int new_index_nr = new_client_nr - 1;
 486   int index_nr_wanted = client_nr_wanted - 1;
 487   struct PlayerInfo *old_player = &stored_player[old_index_nr];
 488   struct PlayerInfo *new_player = &stored_player[new_index_nr];
 489
 490   printf("OP_NUMBER_WANTED: %d\n", old_client_nr);
 491
 492   if (new_client_nr == client_nr_wanted)        /* switching succeeded */
 493   {
 494     struct NetworkClientPlayerInfo *player;
 495
 496     if (old_client_nr != client_nr_wanted)      /* client's nr has changed */
 497       Error(ERR_NETWORK_CLIENT, "client %d switches to # %d",
 498             old_client_nr, new_client_nr);
 499     else if (old_client_nr == first_player.nr)  /* local player keeps his nr */
 500       Error(ERR_NETWORK_CLIENT, "keeping client # %d", new_client_nr);
 501
 502     if (old_client_nr != new_client_nr)
 503     {
 504       /* set relevant player settings and change to new player */
 505
 506       old_player->connected_network = FALSE;
 507       new_player->connected_network = TRUE;
 508     }
 509
 510     player = getNetworkPlayer(old_client_nr);
 511     player->nr = new_client_nr;
 512
 513     if (old_player == local_player)             /* local player switched */
 514     {
 515       local_player = new_player;
 516
 517       old_player->connected_locally = FALSE;
 518       new_player->connected_locally = TRUE;
 519     }
 520   }
 521   else if (old_client_nr == first_player.nr)    /* failed -- local player? */
 522   {
 523     char request[100];
 524
 525     sprintf(request, "Sorry! Player %d already exists! You are player %d!",
 526             index_nr_wanted + 1, new_index_nr + 1);
 527
 528     Request(request, REQ_CONFIRM);
 529
 530     Error(ERR_NETWORK_CLIENT, "cannot switch -- you keep client # %d",
 531           new_client_nr);
 532   }
 533
 534   if (game_status == GAME_MODE_MAIN)
 535     DrawNetworkPlayers();
 536 }
 537
 538 static void Handle_OP_PLAYER_NAME()
 539 {
 540   int player_nr = getNetworkBuffer8BitInteger(read_buffer);
 541   char *player_name = getNetworkBufferString(read_buffer);
 542   struct NetworkClientPlayerInfo *player = getNetworkPlayer(player_nr);
 543
 544   printf("OP_PLAYER_NAME: %d\n", player_nr);
 545
 546   strncpy(player->name, player_name, MAX_PLAYER_NAME_LEN);
 547   player->name[MAX_PLAYER_NAME_LEN] = '\0';
 548
 549   Error(ERR_NETWORK_CLIENT, "client %d calls itself \"%s\"",
 550         player_nr, player->name);
 551 }
 552
 553 static void Handle_OP_PLAYER_CONNECTED()
 554 {
 555   struct NetworkClientPlayerInfo *player, *last_player = NULL;
 556   int new_client_nr = getNetworkBuffer8BitInteger(read_buffer);
 557   int new_index_nr = new_client_nr - 1;
 558
 559   printf("OP_PLAYER_CONNECTED: %d\n", new_client_nr);
 560   Error(ERR_NETWORK_CLIENT, "new client %d connected", new_client_nr);
 561
 562   for (player = &first_player; player; player = player->next)
 563   {
 564     if (player->nr == new_client_nr)
 565       Error(ERR_EXIT, "multiplayer server sent duplicate player id");
 566
 567     last_player = player;
 568   }
 569
 570   last_player->next = player =
 571     checked_malloc(sizeof(struct NetworkClientPlayerInfo));
 572   player->nr = new_client_nr;
 573   player->name[0] = '\0';
 574   player->next = NULL;
 575
 576   stored_player[new_index_nr].connected_network = TRUE;
 577 }
 578
 579 static void Handle_OP_PLAYER_DISCONNECTED()
 580 {
 581   struct NetworkClientPlayerInfo *player, *player_disconnected;
 582   int player_nr = getNetworkBuffer8BitInteger(read_buffer);
 583   int index_nr = player_nr - 1;
 584
 585   printf("OP_PLAYER_DISCONNECTED: %d\n", player_nr);
 586   player_disconnected = getNetworkPlayer(player_nr);
 587   Error(ERR_NETWORK_CLIENT, "client %d (%s) disconnected",
 588         player_nr, getNetworkPlayerName(player_nr));
 589
 590   for (player = &first_player; player; player = player->next)
 591     if (player->next == player_disconnected)
 592       player->next = player_disconnected->next;
 593   free(player_disconnected);
 594
 595   stored_player[index_nr].connected_locally = FALSE;
 596   stored_player[index_nr].connected_network = FALSE;
 597
 598   if (game_status == GAME_MODE_PLAYING)
 599   {
 600     char message[100];
 601
 602     sprintf(message, "Player %d left network server! Network game stopped!",
 603             player_nr);
 604
 605     Request(message, REQ_CONFIRM | REQ_STAY_CLOSED);
 606
 607     SetGameStatus(GAME_MODE_MAIN);
 608
 609     DrawMainMenu();
 610   }
 611   else if (game_status == GAME_MODE_MAIN)
 612   {
 613     DrawNetworkPlayers();
 614   }
 615 }
 616
 617 static void Handle_OP_START_PLAYING()
 618 {
 619   int player_nr = getNetworkBuffer8BitInteger(read_buffer);
 620   char *new_leveldir_identifier = getNetworkBufferString(read_buffer);
 621   int new_level_nr = getNetworkBuffer16BitInteger(read_buffer);
 622   unsigned int new_random_seed = getNetworkBuffer32BitInteger(read_buffer);
 623
 624   LevelDirTree *new_leveldir =
 625     getTreeInfoFromIdentifier(leveldir_first, new_leveldir_identifier);
 626
 627   if (new_leveldir == NULL)
 628   {
 629     Error(ERR_WARN, "no such level identifier: '%s'", new_leveldir_identifier);
 630
 631     stop_network_game = TRUE;
 632
 633     return;
 634   }
 635
 636   printf("OP_START_PLAYING: %d\n", player_nr);
 637   Error(ERR_NETWORK_CLIENT,
 638         "client %d starts game [level %d from level identifier '%s']\n",
 639         player_nr, new_level_nr, new_leveldir->identifier);
 640
 641   leveldir_current = new_leveldir;
 642   level_nr = new_level_nr;
 643
 644   TapeErase();
 645   LoadTape(level_nr);
 646   LoadLevel(level_nr);
 647
 648   StartGameActions(FALSE, setup.autorecord, new_random_seed);
 649 }
 650
 651 static void Handle_OP_PAUSE_PLAYING()
 652 {
 653   int player_nr = getNetworkBuffer8BitInteger(read_buffer);
 654
 655   printf("OP_PAUSE_PLAYING: %d\n", player_nr);
 656   Error(ERR_NETWORK_CLIENT, "client %d pauses game", player_nr);
 657
 658   if (game_status == GAME_MODE_PLAYING)
 659   {
 660     tape.pausing = TRUE;
 661     DrawVideoDisplay(VIDEO_STATE_PAUSE_ON, 0);
 662   }
 663 }
 664
 665 static void Handle_OP_CONTINUE_PLAYING()
 666 {
 667   int player_nr = getNetworkBuffer8BitInteger(read_buffer);
 668
 669   printf("OP_CONTINUE_PLAYING: %d\n", player_nr);
 670   Error(ERR_NETWORK_CLIENT, "client %d continues game", player_nr);
 671
 672   if (game_status == GAME_MODE_PLAYING)
 673   {
 674     tape.pausing = FALSE;
 675     DrawVideoDisplay(VIDEO_STATE_PAUSE_OFF, 0);
 676   }
 677 }
 678
 679 static void Handle_OP_STOP_PLAYING()
 680 {
 681   int client_nr = getNetworkBuffer8BitInteger(read_buffer);
 682   int cause_for_stopping = getNetworkBuffer8BitInteger(read_buffer);
 683
 684   printf("OP_STOP_PLAYING: %d [%d]\n", client_nr, cause_for_stopping);
 685   Error(ERR_NETWORK_CLIENT, "client %d stops game [%d]",
 686         client_nr, cause_for_stopping);
 687
 688   if (game_status == GAME_MODE_PLAYING)
 689   {
 690     int index_nr = client_nr - 1;
 691     struct PlayerInfo *client_player = &stored_player[index_nr];
 692     boolean stopped_by_remote_player = (!client_player->connected_locally);
 693     char message[100];
 694
 695     sprintf(message, (cause_for_stopping == NETWORK_STOP_BY_PLAYER ?
 696                       "Network game stopped by player %d!" :
 697                       cause_for_stopping == NETWORK_STOP_BY_ERROR ?
 698                       "Network game stopped due to internal error!" :
 699                       "Network game stopped!"), client_nr);
 700
 701     if (cause_for_stopping != NETWORK_STOP_BY_PLAYER ||
 702         stopped_by_remote_player)
 703       Request(message, REQ_CONFIRM | REQ_STAY_CLOSED);
 704
 705     SetGameStatus(GAME_MODE_MAIN);
 706
 707     DrawMainMenu();
 708   }
 709 }
 710
 711 static void Handle_OP_MOVE_PLAYER()
 712 {
 713   int player_nr = getNetworkBuffer8BitInteger(read_buffer);
 714   int server_frame_counter = getNetworkBuffer32BitInteger(read_buffer);
 715   int i;
 716
 717   if (!network_playing)
 718     return;
 719
 720   if (server_frame_counter != FrameCounter)
 721   {
 722     Error(ERR_INFO, "frame counters of client %d and server out of sync",
 723           player_nr);
 724     Error(ERR_INFO, "frame counter of client is %d", FrameCounter);
 725     Error(ERR_INFO, "frame counter of server is %d", server_frame_counter);
 726     Error(ERR_INFO, "this should not happen -- please debug");
 727
 728     stop_network_game = TRUE;
 729
 730     return;
 731   }
 732
 733   /* copy valid player actions (will be set to 0 for not connected players) */
 734   for (i = 0; i < MAX_PLAYERS; i++)
 735     stored_player[i].effective_action =
 736       getNetworkBuffer8BitInteger(read_buffer);
 737
 738   network_player_action_received = TRUE;
 739 }
 740
 741 static void Handle_OP_BROADCAST_MESSAGE()
 742 {
 743   int player_nr = getNetworkBuffer8BitInteger(read_buffer);
 744
 745   printf("OP_BROADCAST_MESSAGE: %d\n", player_nr);
 746   Error(ERR_NETWORK_CLIENT, "client %d sends message", player_nr);
 747 }
 748
 749 static void HandleNetworkingMessage()
 750 {
 751   stop_network_game = FALSE;
 752
 753   initNetworkBufferForReading(read_buffer);
 754
 755   int message_type = getNetworkBuffer8BitInteger(read_buffer);
 756
 757   switch (message_type)
 758   {
 759     case OP_BAD_PROTOCOL_VERSION:
 760       Handle_OP_BAD_PROTOCOL_VERSION();
 761       break;
 762
 763     case OP_YOUR_NUMBER:
 764       Handle_OP_YOUR_NUMBER();
 765       break;
 766
 767     case OP_NUMBER_WANTED:
 768       Handle_OP_NUMBER_WANTED();
 769       break;
 770
 771     case OP_PLAYER_NAME:
 772       Handle_OP_PLAYER_NAME();
 773       break;
 774
 775     case OP_PLAYER_CONNECTED:
 776       Handle_OP_PLAYER_CONNECTED();
 777       break;
 778
 779     case OP_PLAYER_DISCONNECTED:
 780       Handle_OP_PLAYER_DISCONNECTED();
 781       break;
 782
 783     case OP_START_PLAYING:
 784       Handle_OP_START_PLAYING();
 785       break;
 786
 787     case OP_PAUSE_PLAYING:
 788       Handle_OP_PAUSE_PLAYING();
 789       break;
 790
 791     case OP_CONTINUE_PLAYING:
 792       Handle_OP_CONTINUE_PLAYING();
 793       break;
 794
 795     case OP_STOP_PLAYING:
 796       Handle_OP_STOP_PLAYING();
 797       break;
 798
 799     case OP_MOVE_PLAYER:
 800       Handle_OP_MOVE_PLAYER();
 801       break;
 802
 803     case OP_BROADCAST_MESSAGE:
 804       Handle_OP_BROADCAST_MESSAGE();
 805       break;
 806
 807     default:
 808       if (options.verbose)
 809         Error(ERR_NETWORK_CLIENT,
 810               "unknown opcode %d from server", message_type);
 811   }
 812
 813   fflush(stdout);
 814
 815   /* in case of internal error, stop network game */
 816   if (stop_network_game)
 817     SendToServer_StopPlaying(NETWORK_STOP_BY_ERROR);
 818 }
 819
 820 static char *HandleNetworkingPackets()
 821 {
 822   while (1)
 823   {
 824     /* ---------- check network server for activity ---------- */
 825
 826     int num_active_sockets = SDLNet_CheckSockets(rfds, 0);
 827
 828     if (num_active_sockets < 0)
 829       return "Error checking network sockets!";
 830
 831     if (num_active_sockets == 0)
 832       break;    // no active sockets, stop here
 833
 834     /* ---------- read packets from network server ---------- */
 835
 836     initNetworkBufferForReceiving(read_buffer);
 837
 838     int num_bytes = receiveNetworkBufferPacket(read_buffer, sfd);
 839
 840     if (num_bytes < 0)
 841       return "Error reading from network server!";
 842
 843     if (num_bytes == 0)
 844       return "Connection to network server lost!";
 845
 846     HandleNetworkingMessage();
 847
 848     if (stop_network_client)
 849       return stop_network_client_message;
 850   }
 851
 852   return NULL;
 853 }
 854
 855 static void FreeNetworkClientPlayerInfo(struct NetworkClientPlayerInfo *player)
 856 {
 857   if (player == NULL)
 858     return;
 859
 860   if (player->next)
 861     FreeNetworkClientPlayerInfo(player->next);
 862
 863   checked_free(player);
 864 }
 865
 866 static void HandleNetworkingDisconnect()
 867 {
 868   int i;
 869
 870   SDLNet_TCP_DelSocket(rfds, sfd);
 871   SDLNet_TCP_Close(sfd);
 872
 873   network_playing = FALSE;
 874
 875   network.enabled = FALSE;
 876   network.connected = FALSE;
 877
 878   setup.network_mode = FALSE;
 879
 880   for (i = 0; i < MAX_PLAYERS; i++)
 881     stored_player[i].connected_network = FALSE;
 882
 883   FreeNetworkClientPlayerInfo(first_player.next);
 884
 885   first_player.nr = 0;
 886   first_player.next = NULL;
 887 }
 888
 889 void HandleNetworking()
 890 {
 891   char *error_message = HandleNetworkingPackets();
 892
 893   if (error_message != NULL)
 894   {
 895     HandleNetworkingDisconnect();
 896
 897     if (game_status == GAME_MODE_PLAYING)
 898     {
 899       Request(error_message, REQ_CONFIRM | REQ_STAY_CLOSED);
 900
 901       SetGameStatus(GAME_MODE_MAIN);
 902
 903       DrawMainMenu();
 904     }
 905     else
 906     {
 907       Request(error_message, REQ_CONFIRM);
 908
 909       if (game_status == GAME_MODE_MAIN)
 910         ClearNetworkPlayers();
 911     }
 912   }
 913 }
 914
 915 void DisconnectFromNetworkServer()
 916 {
 917   DrawNetworkText_Title("Terminating Network");
 918   DrawNetworkText("Disconnecting from network server ...");
 919
 920   HandleNetworkingDisconnect();
 921
 922   DrawNetworkText_Success("Successfully disconnected!");
 923
 924   /* short time to recognize result of network initialization */
 925   Delay_WithScreenUpdates(1000);
 926 }