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 #include "init.h"
  26
  27 struct NetworkClientPlayerInfo
  28 {
  29   byte nr;
  30   char name[MAX_PLAYER_NAME_LEN + 1];
  31   struct NetworkClientPlayerInfo *next;
  32 };
  33
  34 static struct NetworkClientPlayerInfo first_player =
  35 {
  36   0,
  37   EMPTY_PLAYER_NAME,
  38   NULL
  39 };
  40
  41 struct NetworkLevelFileInfo
  42 {
  43   char *leveldir_identifier;
  44   struct LevelFileInfo file_info;
  45   struct LevelFileInfo tmpl_info;
  46   boolean use_network_level_files;
  47   boolean use_custom_template;
  48 };
  49
  50 /* server stuff */
  51
  52 static TCPsocket sfd;           /* TCP server socket */
  53 static UDPsocket udp;           /* UDP server socket */
  54 static SDLNet_SocketSet rfds;   /* socket set */
  55
  56 static struct NetworkBuffer *read_buffer = NULL;
  57 static struct NetworkBuffer *write_buffer = NULL;
  58
  59 static boolean stop_network_game = FALSE;
  60 static boolean stop_network_client = FALSE;
  61 static char stop_network_client_message[MAX_OUTPUT_LINESIZE + 1];
  62
  63 static struct NetworkLevelFileInfo network_level;
  64
  65 static void DrawNetworkTextExt(char *message, int font_nr, boolean initialize)
  66 {
  67   static int xpos = 0, ypos = 0;
  68   static int max_line_width = 0;
  69   int font_width = getFontWidth(font_nr);
  70   int font_height = getFontHeight(font_nr);
  71   int ypos_1 = 120;
  72   int ypos_2 = 150;
  73
  74   if (initialize)
  75   {
  76     if (game_status == GAME_MODE_LOADING)
  77     {
  78       max_line_width = WIN_XSIZE;
  79
  80       xpos = (max_line_width - getTextWidth(message, font_nr)) / 2;
  81       ypos = ypos_1;
  82
  83       DrawText(xpos, ypos, message, font_nr);
  84
  85       xpos = 0;
  86       ypos = ypos_2;
  87     }
  88     else
  89     {
  90       max_line_width = SXSIZE;
  91
  92       DrawTextSCentered(ypos_1, font_nr, message);
  93
  94       /* calculate offset to x position caused by rounding */
  95       int max_chars_per_line = max_line_width / font_width;
  96       int xoffset = (max_line_width - max_chars_per_line * font_width) / 2;
  97
  98       xpos = SX + xoffset;
  99       ypos = SY + ypos_2;
 100     }
 101
 102     Error(ERR_DEBUG, "========== %s ==========", message);
 103   }
 104   else
 105   {
 106     int max_chars_per_line = max_line_width / font_width;
 107     int max_lines_per_text = 10;
 108     int num_lines_spacing = (font_nr == FC_YELLOW ? 1 : 3);
 109     int num_lines_printed = DrawTextBuffer(xpos, ypos, message, font_nr,
 110                                            max_chars_per_line, -1,
 111                                            max_lines_per_text, 0, -1,
 112                                            TRUE, TRUE, FALSE);
 113
 114     ypos += (num_lines_printed + num_lines_spacing) * font_height;
 115
 116     Error(ERR_DEBUG, "%s", message);
 117   }
 118
 119   BackToFront();
 120 }
 121
 122 static void DrawNetworkText(char *message)
 123 {
 124   DrawNetworkTextExt(message, FC_YELLOW, FALSE);
 125 }
 126
 127 static void DrawNetworkText_Success(char *message)
 128 {
 129   DrawNetworkTextExt(message, FC_GREEN, FALSE);
 130 }
 131
 132 static void DrawNetworkText_Failed(char *message)
 133 {
 134   DrawNetworkTextExt(message, FC_RED, FALSE);
 135 }
 136
 137 static void DrawNetworkText_Title(char *message)
 138 {
 139   DrawNetworkTextExt(message, FC_GREEN, TRUE);
 140 }
 141
 142 static void SendNetworkBufferToServer(struct NetworkBuffer *nb)
 143 {
 144   if (!network.enabled)
 145     return;
 146
 147   /* set message length header */
 148   putNetwork32BitInteger(nb->buffer, nb->size - 4);
 149
 150   /* directly send the buffer to the network server */
 151   SDLNet_TCP_Send(sfd, nb->buffer, nb->size);
 152 }
 153
 154 struct NetworkClientPlayerInfo *getNetworkPlayer(int player_nr)
 155 {
 156   struct NetworkClientPlayerInfo *player = NULL;
 157
 158   for (player = &first_player; player; player = player->next)
 159     if (player->nr == player_nr)
 160       break;
 161
 162   if (player == NULL)   /* should not happen */
 163     Error(ERR_EXIT, "protocol error: reference to non-existing player %d",
 164           player_nr);
 165
 166   return player;
 167 }
 168
 169 char *getNetworkPlayerName(int player_nr)
 170 {
 171   struct NetworkClientPlayerInfo *player;
 172
 173   if (player_nr == 0)
 174     return("the network game server");
 175   else if (player_nr == first_player.nr)
 176     return("you");
 177   else
 178     for (player = &first_player; player; player = player->next)
 179       if (player->nr == player_nr && strlen(player->name) > 0)
 180         return(player->name);
 181
 182   return(EMPTY_PLAYER_NAME);
 183 }
 184
 185 static boolean hasPathSeparator(char *s)
 186 {
 187   return (strchr(s, '/') != NULL);
 188 }
 189
 190 static void StartNetworkServer(int port)
 191 {
 192   static int p;
 193
 194   p = port;
 195 #if defined(TARGET_SDL2)
 196   server_thread = SDL_CreateThread(NetworkServerThread,
 197                                    "NetworkServerThread", &p);
 198 #else
 199   server_thread = SDL_CreateThread(NetworkServerThread, &p);
 200 #endif
 201   network_server = TRUE;
 202 }
 203
 204 boolean ConnectToServer(char *hostname, int port)
 205 {
 206   IPaddress ip;
 207   int server_host = 0;
 208   int i;
 209
 210   if (read_buffer == NULL)
 211     read_buffer = newNetworkBuffer();
 212
 213   if (write_buffer == NULL)
 214     write_buffer = newNetworkBuffer();
 215
 216   DrawNetworkText_Title("Initializing Network");
 217
 218   if (port == 0)
 219     port = DEFAULT_SERVER_PORT;
 220
 221   if (hostname == NULL)
 222   {
 223     // if no hostname given, try to auto-detect network server in local network
 224     // by doing a UDP broadcast on the network server port and wait for answer
 225
 226     SDLNet_SocketSet udp_socket_set = SDLNet_AllocSocketSet(1);
 227     if (!udp_socket_set)
 228       Error(ERR_EXIT, "SDLNet_AllocSocketSet() failed: %s"), SDLNet_GetError();
 229
 230     udp = SDLNet_UDP_Open(0);
 231     if(!udp)
 232       Error(ERR_EXIT, "SDLNet_UDP_Open() failed: %s", SDLNet_GetError());
 233
 234     if (SDLNet_UDP_AddSocket(udp_socket_set, udp) == -1)
 235       Error(ERR_EXIT_NETWORK_SERVER, "SDLNet_TCP_AddSocket() failed: %s"),
 236         SDLNet_GetError();
 237
 238     char *data_ptr = "network server UDB broadcast";
 239     int data_len = strlen(data_ptr) + 1;
 240     IPaddress ip_address;
 241
 242     SDLNet_Write32(0xffffffff, &ip_address.host);       /* 255.255.255.255 */
 243     SDLNet_Write16(port,       &ip_address.port);
 244
 245     UDPpacket packet =
 246     {
 247       -1,
 248       (Uint8 *)data_ptr,
 249       data_len,
 250       data_len,
 251       0,
 252       ip_address
 253     };
 254
 255     SDLNet_UDP_Send(udp, -1, &packet);
 256
 257     DrawNetworkText("Looking for local network server ...");
 258
 259     /* wait for any local network server to answer UDP broadcast */
 260     for (i = 0; i < 5; i++)
 261     {
 262       if (SDLNet_CheckSockets(udp_socket_set, 0) == 1)
 263       {
 264         int num_packets = SDLNet_UDP_Recv(udp, &packet);
 265
 266         if (num_packets == 1)
 267         {
 268           DrawNetworkText_Success("Network server found!");
 269
 270           server_host = SDLNet_Read32(&packet.address.host);
 271         }
 272         else
 273         {
 274           DrawNetworkText_Failed("No answer from network server!");
 275         }
 276
 277         break;
 278       }
 279       else
 280       {
 281         Delay_WithScreenUpdates(100);
 282       }
 283     }
 284
 285     if (server_host == 0)
 286       DrawNetworkText_Failed("No network server found!");
 287   }
 288
 289   rfds = SDLNet_AllocSocketSet(1);
 290
 291   if (hostname)
 292   {
 293     SDLNet_ResolveHost(&ip, hostname, port);
 294
 295     if (ip.host == INADDR_NONE)
 296       Error(ERR_EXIT, "cannot locate host '%s'", hostname);
 297     else
 298       server_host = SDLNet_Read32(&ip.host);
 299
 300     DrawNetworkText("Connecting to remote host ...");
 301   }
 302   else
 303   {
 304     // if no hostname was given and no network server was auto-detected in the
 305     // local network, try to connect to a network server at the local host
 306     if (server_host == 0)
 307       server_host = 0x7f000001;                 /* 127.0.0.1 */
 308
 309     SDLNet_Write32(server_host, &ip.host);
 310     SDLNet_Write16(port,        &ip.port);
 311
 312     DrawNetworkText("Connecting to local host ...");
 313   }
 314
 315   Error(ERR_DEBUG, "trying to connect to network server at %d.%d.%d.%d ...",
 316         (server_host >> 24) & 0xff,
 317         (server_host >> 16) & 0xff,
 318         (server_host >>  8) & 0xff,
 319         (server_host >>  0) & 0xff);
 320
 321   sfd = SDLNet_TCP_Open(&ip);
 322
 323   if (sfd)
 324   {
 325     SDLNet_TCP_AddSocket(rfds, sfd);
 326
 327     DrawNetworkText_Success("Successfully connected!");
 328
 329     return TRUE;
 330   }
 331   else
 332   {
 333     DrawNetworkText_Failed("Failed to connect to network server!");
 334
 335     printf("SDLNet_TCP_Open(): %s\n", SDLNet_GetError());
 336   }
 337
 338   if (hostname)                 /* connect to specified server failed */
 339     return FALSE;
 340
 341   DrawNetworkText("Starting new local network server ...");
 342
 343   StartNetworkServer(port);
 344
 345   /* wait for server to start up and try connecting several times */
 346   for (i = 0; i < 30; i++)
 347   {
 348     if ((sfd = SDLNet_TCP_Open(&ip)))           /* connected */
 349     {
 350       DrawNetworkText_Success("Successfully connected!");
 351
 352       SDLNet_TCP_AddSocket(rfds, sfd);
 353       return TRUE;
 354     }
 355
 356     Delay_WithScreenUpdates(100);
 357   }
 358
 359   DrawNetworkText_Failed("Failed to connect to network server!");
 360
 361   /* when reaching this point, connect to newly started server has failed */
 362   return FALSE;
 363 }
 364
 365 void SendToServer_PlayerName(char *player_name)
 366 {
 367   initNetworkBufferForWriting(write_buffer, OP_PLAYER_NAME, 0);
 368
 369   putNetworkBufferString(write_buffer, player_name);
 370
 371   SendNetworkBufferToServer(write_buffer);
 372
 373   Error(ERR_NETWORK_CLIENT, "you set your player name to \"%s\"", player_name);
 374 }
 375
 376 void SendToServer_ProtocolVersion()
 377 {
 378   initNetworkBufferForWriting(write_buffer, OP_PROTOCOL_VERSION, 0);
 379
 380   putNetworkBuffer8BitInteger(write_buffer, PROTOCOL_VERSION_MAJOR);
 381   putNetworkBuffer8BitInteger(write_buffer, PROTOCOL_VERSION_MINOR);
 382   putNetworkBuffer8BitInteger(write_buffer, PROTOCOL_VERSION_PATCH);
 383
 384   SendNetworkBufferToServer(write_buffer);
 385 }
 386
 387 void SendToServer_NrWanted(int nr_wanted)
 388 {
 389   initNetworkBufferForWriting(write_buffer, OP_NUMBER_WANTED, 0);
 390
 391   putNetworkBuffer8BitInteger(write_buffer, nr_wanted);
 392
 393   SendNetworkBufferToServer(write_buffer);
 394 }
 395
 396 void SendToServer_LevelFile()
 397 {
 398   initNetworkBufferForWriting(write_buffer, OP_LEVEL_FILE, 0);
 399
 400   putNetworkBufferString(      write_buffer, leveldir_current->identifier);
 401   putNetworkBuffer16BitInteger(write_buffer, level.file_info.nr);
 402   putNetworkBuffer8BitInteger( write_buffer, level.file_info.type);
 403   putNetworkBuffer8BitInteger( write_buffer, level.file_info.packed);
 404   putNetworkBufferString(      write_buffer, level.file_info.basename);
 405   putNetworkBufferFile(        write_buffer, level.file_info.filename);
 406   putNetworkBuffer8BitInteger( write_buffer, level.use_custom_template);
 407
 408   if (level.use_custom_template)
 409   {
 410     putNetworkBufferString(write_buffer, level_template.file_info.basename);
 411     putNetworkBufferFile(  write_buffer, level_template.file_info.filename);
 412   }
 413
 414   SendNetworkBufferToServer(write_buffer);
 415
 416   setString(&network_level.leveldir_identifier, leveldir_current->identifier);
 417
 418   /* the sending client does not use network level files (but the real ones) */
 419   network_level.use_network_level_files = FALSE;
 420
 421 #if 0
 422   printf("::: '%s'\n", leveldir_current->identifier);
 423   printf("::: '%d'\n", level.file_info.nr);
 424   printf("::: '%d'\n", level.file_info.type);
 425   printf("::: '%d'\n", level.file_info.packed);
 426   printf("::: '%s'\n", level.file_info.basename);
 427   printf("::: '%s'\n", level.file_info.filename);
 428
 429   if (level.use_custom_template)
 430     printf("::: '%s'\n", level_template.file_info.filename);
 431 #endif
 432 }
 433
 434 void SendToServer_StartPlaying()
 435 {
 436   unsigned int new_random_seed = InitRND(level.random_seed);
 437
 438   initNetworkBufferForWriting(write_buffer, OP_START_PLAYING, 0);
 439
 440   putNetworkBufferString(      write_buffer, leveldir_current->identifier);
 441   putNetworkBuffer16BitInteger(write_buffer, level_nr);
 442   putNetworkBuffer32BitInteger(write_buffer, new_random_seed);
 443
 444   SendNetworkBufferToServer(write_buffer);
 445 }
 446
 447 void SendToServer_PausePlaying()
 448 {
 449   initNetworkBufferForWriting(write_buffer, OP_PAUSE_PLAYING, 0);
 450
 451   SendNetworkBufferToServer(write_buffer);
 452 }
 453
 454 void SendToServer_ContinuePlaying()
 455 {
 456   initNetworkBufferForWriting(write_buffer, OP_CONTINUE_PLAYING, 0);
 457
 458   SendNetworkBufferToServer(write_buffer);
 459 }
 460
 461 void SendToServer_StopPlaying(int cause_for_stopping)
 462 {
 463   initNetworkBufferForWriting(write_buffer, OP_STOP_PLAYING, 0);
 464
 465   putNetworkBuffer8BitInteger(write_buffer, cause_for_stopping);
 466
 467   SendNetworkBufferToServer(write_buffer);
 468 }
 469
 470 void SendToServer_MovePlayer(byte player_action)
 471 {
 472   initNetworkBufferForWriting(write_buffer, OP_MOVE_PLAYER, 0);
 473
 474   putNetworkBuffer8BitInteger(write_buffer, player_action);
 475
 476   SendNetworkBufferToServer(write_buffer);
 477 }
 478
 479 static void Handle_OP_BAD_PROTOCOL_VERSION()
 480 {
 481   int protocol_version_major = getNetworkBuffer8BitInteger(read_buffer);
 482   int protocol_version_minor = getNetworkBuffer8BitInteger(read_buffer);
 483
 484   Error(ERR_WARN, "protocol version mismatch");
 485   Error(ERR_WARN, "server expects %d.%d.x instead of %d.%d.%d",
 486         protocol_version_major,
 487         protocol_version_minor,
 488         PROTOCOL_VERSION_MAJOR,
 489         PROTOCOL_VERSION_MINOR,
 490         PROTOCOL_VERSION_PATCH);
 491
 492   sprintf(stop_network_client_message, "Network protocol version mismatch! Server expects version %d.%d.x instead of %d.%d.%d!",
 493           protocol_version_major,
 494           protocol_version_minor,
 495           PROTOCOL_VERSION_MAJOR,
 496           PROTOCOL_VERSION_MINOR,
 497           PROTOCOL_VERSION_PATCH);
 498
 499   stop_network_client = TRUE;
 500 }
 501
 502 static void Handle_OP_YOUR_NUMBER()
 503 {
 504   int old_client_nr = getNetworkBuffer8BitInteger(read_buffer);
 505   int new_client_nr = getNetworkBuffer8BitInteger(read_buffer);
 506   int new_index_nr = new_client_nr - 1;
 507   struct PlayerInfo *old_local_player = local_player;
 508   struct PlayerInfo *new_local_player = &stored_player[new_index_nr];
 509
 510   printf("OP_YOUR_NUMBER: %d\n", old_client_nr);
 511   first_player.nr = new_client_nr;
 512
 513   if (old_local_player != new_local_player)
 514   {
 515     /* set relevant player settings and change to new player */
 516
 517     local_player = new_local_player;
 518
 519     old_local_player->connected_locally = FALSE;
 520     new_local_player->connected_locally = TRUE;
 521
 522     old_local_player->connected_network = FALSE;
 523     new_local_player->connected_network = TRUE;
 524   }
 525
 526   if (first_player.nr > MAX_PLAYERS)
 527     Error(ERR_EXIT, "sorry, more than %d players not allowed", MAX_PLAYERS);
 528
 529   Error(ERR_NETWORK_CLIENT, "you get client # %d", new_client_nr);
 530
 531   stored_player[new_index_nr].connected_network = TRUE;
 532 }
 533
 534 static void Handle_OP_NUMBER_WANTED()
 535 {
 536   int old_client_nr    = getNetworkBuffer8BitInteger(read_buffer);
 537   int client_nr_wanted = getNetworkBuffer8BitInteger(read_buffer);
 538   int new_client_nr    = getNetworkBuffer8BitInteger(read_buffer);
 539   int old_index_nr = old_client_nr - 1;
 540   int new_index_nr = new_client_nr - 1;
 541   int index_nr_wanted = client_nr_wanted - 1;
 542   struct PlayerInfo *old_player = &stored_player[old_index_nr];
 543   struct PlayerInfo *new_player = &stored_player[new_index_nr];
 544
 545   printf("OP_NUMBER_WANTED: %d\n", old_client_nr);
 546
 547   if (new_client_nr == client_nr_wanted)        /* switching succeeded */
 548   {
 549     struct NetworkClientPlayerInfo *player;
 550
 551     if (old_client_nr != client_nr_wanted)      /* client's nr has changed */
 552       Error(ERR_NETWORK_CLIENT, "client %d switches to # %d",
 553             old_client_nr, new_client_nr);
 554     else if (old_client_nr == first_player.nr)  /* local player keeps his nr */
 555       Error(ERR_NETWORK_CLIENT, "keeping client # %d", new_client_nr);
 556
 557     if (old_client_nr != new_client_nr)
 558     {
 559       /* set relevant player settings and change to new player */
 560
 561       old_player->connected_network = FALSE;
 562       new_player->connected_network = TRUE;
 563     }
 564
 565     player = getNetworkPlayer(old_client_nr);
 566     player->nr = new_client_nr;
 567
 568     if (old_player == local_player)             /* local player switched */
 569     {
 570       local_player = new_player;
 571
 572       old_player->connected_locally = FALSE;
 573       new_player->connected_locally = TRUE;
 574     }
 575   }
 576   else if (old_client_nr == first_player.nr)    /* failed -- local player? */
 577   {
 578     char request[100];
 579
 580     sprintf(request, "Sorry! Player %d already exists! You are player %d!",
 581             index_nr_wanted + 1, new_index_nr + 1);
 582
 583     Request(request, REQ_CONFIRM);
 584
 585     Error(ERR_NETWORK_CLIENT, "cannot switch -- you keep client # %d",
 586           new_client_nr);
 587   }
 588
 589   if (game_status == GAME_MODE_MAIN)
 590     DrawNetworkPlayers();
 591 }
 592
 593 static void Handle_OP_PLAYER_NAME()
 594 {
 595   int player_nr = getNetworkBuffer8BitInteger(read_buffer);
 596   char *player_name = getNetworkBufferString(read_buffer);
 597   struct NetworkClientPlayerInfo *player = getNetworkPlayer(player_nr);
 598
 599   printf("OP_PLAYER_NAME: %d\n", player_nr);
 600
 601   strncpy(player->name, player_name, MAX_PLAYER_NAME_LEN);
 602   player->name[MAX_PLAYER_NAME_LEN] = '\0';
 603
 604   Error(ERR_NETWORK_CLIENT, "client %d calls itself \"%s\"",
 605         player_nr, player->name);
 606 }
 607
 608 static void Handle_OP_PLAYER_CONNECTED()
 609 {
 610   struct NetworkClientPlayerInfo *player, *last_player = NULL;
 611   int new_client_nr = getNetworkBuffer8BitInteger(read_buffer);
 612   int new_index_nr = new_client_nr - 1;
 613
 614   printf("OP_PLAYER_CONNECTED: %d\n", new_client_nr);
 615   Error(ERR_NETWORK_CLIENT, "new client %d connected", new_client_nr);
 616
 617   for (player = &first_player; player; player = player->next)
 618   {
 619     if (player->nr == new_client_nr)
 620       Error(ERR_EXIT, "multiplayer server sent duplicate player id");
 621
 622     last_player = player;
 623   }
 624
 625   last_player->next = player =
 626     checked_malloc(sizeof(struct NetworkClientPlayerInfo));
 627   player->nr = new_client_nr;
 628   player->name[0] = '\0';
 629   player->next = NULL;
 630
 631   stored_player[new_index_nr].connected_network = TRUE;
 632 }
 633
 634 static void Handle_OP_PLAYER_DISCONNECTED()
 635 {
 636   struct NetworkClientPlayerInfo *player, *player_disconnected;
 637   int player_nr = getNetworkBuffer8BitInteger(read_buffer);
 638   int index_nr = player_nr - 1;
 639
 640   printf("OP_PLAYER_DISCONNECTED: %d\n", player_nr);
 641   player_disconnected = getNetworkPlayer(player_nr);
 642   Error(ERR_NETWORK_CLIENT, "client %d (%s) disconnected",
 643         player_nr, getNetworkPlayerName(player_nr));
 644
 645   for (player = &first_player; player; player = player->next)
 646     if (player->next == player_disconnected)
 647       player->next = player_disconnected->next;
 648   free(player_disconnected);
 649
 650   stored_player[index_nr].connected_locally = FALSE;
 651   stored_player[index_nr].connected_network = FALSE;
 652
 653   if (game_status == GAME_MODE_PLAYING)
 654   {
 655     char message[100];
 656
 657     sprintf(message, "Player %d left network server! Network game stopped!",
 658             player_nr);
 659
 660     Request(message, REQ_CONFIRM | REQ_STAY_CLOSED);
 661
 662     SetGameStatus(GAME_MODE_MAIN);
 663
 664     DrawMainMenu();
 665   }
 666   else if (game_status == GAME_MODE_MAIN)
 667   {
 668     DrawNetworkPlayers();
 669   }
 670 }
 671
 672 static void Handle_OP_START_PLAYING()
 673 {
 674   int player_nr = getNetworkBuffer8BitInteger(read_buffer);
 675   char *new_leveldir_identifier = getNetworkBufferString(read_buffer);
 676   int new_level_nr = getNetworkBuffer16BitInteger(read_buffer);
 677   unsigned int new_random_seed = getNetworkBuffer32BitInteger(read_buffer);
 678
 679   if (!strEqual(new_leveldir_identifier, network_level.leveldir_identifier))
 680   {
 681     Error(ERR_WARN, "no such level identifier: '%s'", new_leveldir_identifier);
 682
 683     stop_network_game = TRUE;
 684
 685     return;
 686   }
 687
 688   printf("OP_START_PLAYING: %d\n", player_nr);
 689   Error(ERR_NETWORK_CLIENT,
 690         "client %d starts game [level %d from level identifier '%s']\n",
 691         player_nr, new_level_nr, new_leveldir_identifier);
 692
 693   LevelDirTree *new_leveldir =
 694     getTreeInfoFromIdentifier(leveldir_first, new_leveldir_identifier);
 695
 696   if (new_leveldir != NULL)
 697   {
 698     leveldir_current = new_leveldir;
 699     level_nr = new_level_nr;
 700   }
 701
 702   SetLevelSetInfo(new_leveldir_identifier, new_level_nr);
 703
 704   /* needed if level set of network game changed graphics, sounds or music */
 705   ReloadCustomArtwork(0);
 706
 707   TapeErase();
 708
 709   if (network_level.use_network_level_files)
 710     LoadLevelFromNetwork(&network_level.file_info,
 711                          &network_level.tmpl_info);
 712   else
 713     LoadLevel(level_nr);
 714
 715   StartGameActions(FALSE, setup.autorecord, new_random_seed);
 716 }
 717
 718 static void Handle_OP_PAUSE_PLAYING()
 719 {
 720   int player_nr = getNetworkBuffer8BitInteger(read_buffer);
 721
 722   printf("OP_PAUSE_PLAYING: %d\n", player_nr);
 723   Error(ERR_NETWORK_CLIENT, "client %d pauses game", player_nr);
 724
 725   if (game_status == GAME_MODE_PLAYING)
 726   {
 727     tape.pausing = TRUE;
 728     DrawVideoDisplay(VIDEO_STATE_PAUSE_ON, 0);
 729   }
 730 }
 731
 732 static void Handle_OP_CONTINUE_PLAYING()
 733 {
 734   int player_nr = getNetworkBuffer8BitInteger(read_buffer);
 735
 736   printf("OP_CONTINUE_PLAYING: %d\n", player_nr);
 737   Error(ERR_NETWORK_CLIENT, "client %d continues game", player_nr);
 738
 739   if (game_status == GAME_MODE_PLAYING)
 740   {
 741     tape.pausing = FALSE;
 742     DrawVideoDisplay(VIDEO_STATE_PAUSE_OFF, 0);
 743   }
 744 }
 745
 746 static void Handle_OP_STOP_PLAYING()
 747 {
 748   int client_nr = getNetworkBuffer8BitInteger(read_buffer);
 749   int cause_for_stopping = getNetworkBuffer8BitInteger(read_buffer);
 750
 751   printf("OP_STOP_PLAYING: %d [%d]\n", client_nr, cause_for_stopping);
 752   Error(ERR_NETWORK_CLIENT, "client %d stops game [%d]",
 753         client_nr, cause_for_stopping);
 754
 755   if (game_status == GAME_MODE_PLAYING)
 756   {
 757     int index_nr = client_nr - 1;
 758     struct PlayerInfo *client_player = &stored_player[index_nr];
 759     boolean stopped_by_remote_player = (!client_player->connected_locally);
 760     char message[100];
 761
 762     sprintf(message, (cause_for_stopping == NETWORK_STOP_BY_PLAYER ?
 763                       "Network game stopped by player %d!" :
 764                       cause_for_stopping == NETWORK_STOP_BY_ERROR ?
 765                       "Network game stopped due to internal error!" :
 766                       "Network game stopped!"), client_nr);
 767
 768     if (cause_for_stopping != NETWORK_STOP_BY_PLAYER ||
 769         stopped_by_remote_player)
 770       Request(message, REQ_CONFIRM | REQ_STAY_CLOSED);
 771
 772     SetGameStatus(GAME_MODE_MAIN);
 773
 774     DrawMainMenu();
 775   }
 776 }
 777
 778 static void Handle_OP_MOVE_PLAYER()
 779 {
 780   int player_nr = getNetworkBuffer8BitInteger(read_buffer);
 781   int server_frame_counter = getNetworkBuffer32BitInteger(read_buffer);
 782   int i;
 783
 784   if (!network_playing)
 785     return;
 786
 787   if (server_frame_counter != FrameCounter)
 788   {
 789     Error(ERR_INFO, "frame counters of client %d and server out of sync",
 790           player_nr);
 791     Error(ERR_INFO, "frame counter of client is %d", FrameCounter);
 792     Error(ERR_INFO, "frame counter of server is %d", server_frame_counter);
 793     Error(ERR_INFO, "this should not happen -- please debug");
 794
 795     stop_network_game = TRUE;
 796
 797     return;
 798   }
 799
 800   /* copy valid player actions (will be set to 0 for not connected players) */
 801   for (i = 0; i < MAX_PLAYERS; i++)
 802     stored_player[i].effective_action =
 803       getNetworkBuffer8BitInteger(read_buffer);
 804
 805   network_player_action_received = TRUE;
 806 }
 807
 808 static void Handle_OP_BROADCAST_MESSAGE()
 809 {
 810   int player_nr = getNetworkBuffer8BitInteger(read_buffer);
 811
 812   printf("OP_BROADCAST_MESSAGE: %d\n", player_nr);
 813   Error(ERR_NETWORK_CLIENT, "client %d sends message", player_nr);
 814 }
 815
 816 static void Handle_OP_LEVEL_FILE()
 817 {
 818   int player_nr = getNetworkBuffer8BitInteger(read_buffer);
 819   char *leveldir_identifier;
 820   char *network_level_dir;
 821   struct LevelFileInfo *file_info = &network_level.file_info;
 822   struct LevelFileInfo *tmpl_info = &network_level.tmpl_info;
 823   boolean use_custom_template;
 824
 825   setString(&network_level.leveldir_identifier, NULL);
 826   setString(&network_level.file_info.basename,  NULL);
 827   setString(&network_level.file_info.filename,  NULL);
 828   setString(&network_level.tmpl_info.basename,  NULL);
 829   setString(&network_level.tmpl_info.filename,  NULL);
 830
 831   printf("OP_LEVEL_FILE: %d\n", player_nr);
 832
 833   leveldir_identifier = getStringCopy(getNetworkBufferString(read_buffer));
 834
 835   if (hasPathSeparator(leveldir_identifier))
 836     Error(ERR_EXIT, "protocol error: invalid filename from network client");
 837
 838   InitNetworkLevelDirectory(leveldir_identifier);
 839
 840   network_level_dir   = getNetworkLevelDir(leveldir_identifier);
 841
 842   file_info->nr       = getNetworkBuffer16BitInteger(read_buffer);
 843   file_info->type     = getNetworkBuffer8BitInteger(read_buffer);
 844   file_info->packed   = getNetworkBuffer8BitInteger(read_buffer);
 845   file_info->basename = getStringCopy(getNetworkBufferString(read_buffer));
 846   file_info->filename = getPath2(network_level_dir, file_info->basename);
 847
 848   if (hasPathSeparator(file_info->basename))
 849     Error(ERR_EXIT, "protocol error: invalid filename from network client");
 850
 851   getNetworkBufferFile(read_buffer, file_info->filename);
 852
 853   use_custom_template = getNetworkBuffer8BitInteger(read_buffer);
 854   if (use_custom_template)
 855   {
 856     *tmpl_info = *file_info;
 857
 858     tmpl_info->basename = getStringCopy(getNetworkBufferString(read_buffer));
 859     tmpl_info->filename = getPath2(network_level_dir, tmpl_info->basename);
 860
 861     if (hasPathSeparator(tmpl_info->basename))
 862       Error(ERR_EXIT, "protocol error: invalid filename from network client");
 863
 864     getNetworkBufferFile(read_buffer, tmpl_info->filename);
 865   }
 866
 867   network_level.leveldir_identifier = leveldir_identifier;
 868   network_level.use_custom_template = use_custom_template;
 869
 870   /* the receiving client(s) use(s) the transferred network level files */
 871   network_level.use_network_level_files = TRUE;
 872
 873 #if 0
 874   printf("::: '%s'\n", leveldir_identifier);
 875   printf("::: '%d'\n", file_info->nr);
 876   printf("::: '%d'\n", file_info->type);
 877   printf("::: '%d'\n", file_info->packed);
 878   printf("::: '%s'\n", file_info->basename);
 879   printf("::: '%s'\n", file_info->filename);
 880
 881   if (use_custom_template)
 882     printf("::: '%s'\n", tmpl_info->filename);
 883 #endif
 884 }
 885
 886 static void HandleNetworkingMessage()
 887 {
 888   stop_network_game = FALSE;
 889
 890   initNetworkBufferForReading(read_buffer);
 891
 892   int message_type = getNetworkBuffer8BitInteger(read_buffer);
 893
 894   switch (message_type)
 895   {
 896     case OP_BAD_PROTOCOL_VERSION:
 897       Handle_OP_BAD_PROTOCOL_VERSION();
 898       break;
 899
 900     case OP_YOUR_NUMBER:
 901       Handle_OP_YOUR_NUMBER();
 902       break;
 903
 904     case OP_NUMBER_WANTED:
 905       Handle_OP_NUMBER_WANTED();
 906       break;
 907
 908     case OP_PLAYER_NAME:
 909       Handle_OP_PLAYER_NAME();
 910       break;
 911
 912     case OP_PLAYER_CONNECTED:
 913       Handle_OP_PLAYER_CONNECTED();
 914       break;
 915
 916     case OP_PLAYER_DISCONNECTED:
 917       Handle_OP_PLAYER_DISCONNECTED();
 918       break;
 919
 920     case OP_START_PLAYING:
 921       Handle_OP_START_PLAYING();
 922       break;
 923
 924     case OP_PAUSE_PLAYING:
 925       Handle_OP_PAUSE_PLAYING();
 926       break;
 927
 928     case OP_CONTINUE_PLAYING:
 929       Handle_OP_CONTINUE_PLAYING();
 930       break;
 931
 932     case OP_STOP_PLAYING:
 933       Handle_OP_STOP_PLAYING();
 934       break;
 935
 936     case OP_MOVE_PLAYER:
 937       Handle_OP_MOVE_PLAYER();
 938       break;
 939
 940     case OP_BROADCAST_MESSAGE:
 941       Handle_OP_BROADCAST_MESSAGE();
 942       break;
 943
 944     case OP_LEVEL_FILE:
 945       Handle_OP_LEVEL_FILE();
 946       break;
 947
 948     default:
 949       if (options.verbose)
 950         Error(ERR_NETWORK_CLIENT,
 951               "unknown opcode %d from server", message_type);
 952   }
 953
 954   fflush(stdout);
 955
 956   /* in case of internal error, stop network game */
 957   if (stop_network_game)
 958     SendToServer_StopPlaying(NETWORK_STOP_BY_ERROR);
 959 }
 960
 961 static char *HandleNetworkingPackets()
 962 {
 963   while (1)
 964   {
 965     /* ---------- check network server for activity ---------- */
 966
 967     int num_active_sockets = SDLNet_CheckSockets(rfds, 0);
 968
 969     if (num_active_sockets < 0)
 970       return "Error checking network sockets!";
 971
 972     if (num_active_sockets == 0)
 973       break;    // no active sockets, stop here
 974
 975     /* ---------- read packets from network server ---------- */
 976
 977     initNetworkBufferForReceiving(read_buffer);
 978
 979     int num_bytes = receiveNetworkBufferPacket(read_buffer, sfd);
 980
 981     if (num_bytes < 0)
 982       return "Error reading from network server!";
 983
 984     if (num_bytes == 0)
 985       return "Connection to network server lost!";
 986
 987     HandleNetworkingMessage();
 988
 989     if (stop_network_client)
 990       return stop_network_client_message;
 991   }
 992
 993   return NULL;
 994 }
 995
 996 static void FreeNetworkClientPlayerInfo(struct NetworkClientPlayerInfo *player)
 997 {
 998   if (player == NULL)
 999     return;
1000
1001   if (player->next)
1002     FreeNetworkClientPlayerInfo(player->next);
1003
1004   checked_free(player);
1005 }
1006
1007 static void HandleNetworkingDisconnect()
1008 {
1009   int i;
1010
1011   SDLNet_TCP_DelSocket(rfds, sfd);
1012   SDLNet_TCP_Close(sfd);
1013
1014   network_playing = FALSE;
1015
1016   network.enabled = FALSE;
1017   network.connected = FALSE;
1018
1019   setup.network_mode = FALSE;
1020
1021   for (i = 0; i < MAX_PLAYERS; i++)
1022     stored_player[i].connected_network = FALSE;
1023
1024   FreeNetworkClientPlayerInfo(first_player.next);
1025
1026   first_player.nr = 0;
1027   first_player.next = NULL;
1028 }
1029
1030 void HandleNetworking()
1031 {
1032   char *error_message = HandleNetworkingPackets();
1033
1034   if (error_message != NULL)
1035   {
1036     HandleNetworkingDisconnect();
1037
1038     if (game_status == GAME_MODE_PLAYING)
1039     {
1040       Request(error_message, REQ_CONFIRM | REQ_STAY_CLOSED);
1041
1042       SetGameStatus(GAME_MODE_MAIN);
1043
1044       DrawMainMenu();
1045     }
1046     else
1047     {
1048       Request(error_message, REQ_CONFIRM);
1049
1050       if (game_status == GAME_MODE_MAIN)
1051         ClearNetworkPlayers();
1052     }
1053   }
1054 }
1055
1056 void DisconnectFromNetworkServer()
1057 {
1058   DrawNetworkText_Title("Terminating Network");
1059   DrawNetworkText("Disconnecting from network server ...");
1060
1061   HandleNetworkingDisconnect();
1062
1063   DrawNetworkText_Success("Successfully disconnected!");
1064
1065   /* short time to recognize result of network initialization */
1066   Delay_WithScreenUpdates(1000);
1067 }