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 // server stuff
  42
  43 static TCPsocket sfd;           // TCP server socket
  44 static UDPsocket udp;           // UDP server socket
  45 static SDLNet_SocketSet rfds;   // socket set
  46
  47 static struct NetworkBuffer *read_buffer = NULL;
  48 static struct NetworkBuffer *write_buffer = NULL;
  49
  50 static boolean stop_network_game = FALSE;
  51 static boolean stop_network_client = FALSE;
  52 static char stop_network_client_message[MAX_OUTPUT_LINESIZE + 1];
  53
  54 static struct NetworkLevelInfo network_level;
  55
  56 static void DrawNetworkTextExt(char *message, int font_nr, boolean initialize)
  57 {
  58   static int xpos = 0, ypos = 0;
  59   static int max_line_width = 0;
  60   int font_width = getFontWidth(font_nr);
  61   int font_height = getFontHeight(font_nr);
  62   int ypos_1 = 120;
  63   int ypos_2 = 150;
  64
  65   if (initialize)
  66   {
  67     if (game_status == GAME_MODE_LOADING)
  68     {
  69       max_line_width = WIN_XSIZE;
  70
  71       xpos = (max_line_width - getTextWidth(message, font_nr)) / 2;
  72       ypos = ypos_1;
  73
  74       DrawText(xpos, ypos, message, font_nr);
  75
  76       xpos = 0;
  77       ypos = ypos_2;
  78     }
  79     else
  80     {
  81       max_line_width = SXSIZE;
  82
  83       DrawTextSCentered(ypos_1, font_nr, message);
  84
  85       // calculate offset to x position caused by rounding
  86       int max_chars_per_line = max_line_width / font_width;
  87       int xoffset = (max_line_width - max_chars_per_line * font_width) / 2;
  88
  89       xpos = SX + xoffset;
  90       ypos = SY + ypos_2;
  91     }
  92
  93     Error(ERR_DEBUG, "========== %s ==========", message);
  94   }
  95   else
  96   {
  97     int max_chars_per_line = max_line_width / font_width;
  98     int max_lines_per_text = 10;
  99     int num_lines_spacing = (font_nr == FC_YELLOW ? 1 : 3);
 100     int num_lines_printed = DrawTextBuffer(xpos, ypos, message, font_nr,
 101                                            max_chars_per_line, -1,
 102                                            max_lines_per_text, 0, -1,
 103                                            TRUE, TRUE, FALSE);
 104
 105     ypos += (num_lines_printed + num_lines_spacing) * font_height;
 106
 107     Error(ERR_DEBUG, "%s", message);
 108   }
 109
 110   BackToFront();
 111 }
 112
 113 static void DrawNetworkText(char *message)
 114 {
 115   DrawNetworkTextExt(message, FC_YELLOW, FALSE);
 116 }
 117
 118 static void DrawNetworkText_Success(char *message)
 119 {
 120   DrawNetworkTextExt(message, FC_GREEN, FALSE);
 121 }
 122
 123 static void DrawNetworkText_Failed(char *message)
 124 {
 125   DrawNetworkTextExt(message, FC_RED, FALSE);
 126 }
 127
 128 static void DrawNetworkText_Title(char *message)
 129 {
 130   DrawNetworkTextExt(message, FC_GREEN, TRUE);
 131 }
 132
 133 static void SendNetworkBufferToServer(struct NetworkBuffer *nb)
 134 {
 135   if (!network.enabled)
 136     return;
 137
 138   // set message length header
 139   putNetwork32BitInteger(nb->buffer, nb->size - 4);
 140
 141   // directly send the buffer to the network server
 142   SDLNet_TCP_Send(sfd, nb->buffer, nb->size);
 143 }
 144
 145 static struct NetworkClientPlayerInfo *getNetworkPlayer(int player_nr)
 146 {
 147   struct NetworkClientPlayerInfo *player = NULL;
 148
 149   for (player = &first_player; player; player = player->next)
 150     if (player->nr == player_nr)
 151       break;
 152
 153   if (player == NULL)   // should not happen
 154     Error(ERR_EXIT, "protocol error: reference to non-existing player %d",
 155           player_nr);
 156
 157   return player;
 158 }
 159
 160 char *getNetworkPlayerName(int player_nr)
 161 {
 162   struct NetworkClientPlayerInfo *player;
 163
 164   if (player_nr == 0)
 165     return("the network game server");
 166   else if (player_nr == first_player.nr)
 167     return("you");
 168   else
 169     for (player = &first_player; player; player = player->next)
 170       if (player->nr == player_nr && strlen(player->name) > 0)
 171         return(player->name);
 172
 173   return(EMPTY_PLAYER_NAME);
 174 }
 175
 176 boolean hasStartedNetworkGame(void)
 177 {
 178   return !network_level.use_network_level_files;
 179 }
 180
 181 static boolean hasPathSeparator(char *s)
 182 {
 183   return (strchr(s, '/') != NULL);
 184 }
 185
 186 static void StartNetworkServer(int port)
 187 {
 188   static int p;
 189
 190   p = port;
 191 #if defined(TARGET_SDL2)
 192   server_thread = SDL_CreateThread(NetworkServerThread,
 193                                    "NetworkServerThread", &p);
 194 #else
 195   server_thread = SDL_CreateThread(NetworkServerThread, &p);
 196 #endif
 197   network_server = TRUE;
 198 }
 199
 200 boolean ConnectToServer(char *hostname, int port)
 201 {
 202   IPaddress ip;
 203   int server_host = 0;
 204   int i;
 205
 206   if (read_buffer == NULL)
 207     read_buffer = newNetworkBuffer();
 208
 209   if (write_buffer == NULL)
 210     write_buffer = newNetworkBuffer();
 211
 212   DrawNetworkText_Title("Initializing Network");
 213
 214   if (port == 0)
 215     port = DEFAULT_SERVER_PORT;
 216
 217   if (hostname == NULL)
 218   {
 219     // if no hostname given, try to auto-detect network server in local network
 220     // by doing a UDP broadcast on the network server port and wait for answer
 221
 222     SDLNet_SocketSet udp_socket_set = SDLNet_AllocSocketSet(1);
 223     if (!udp_socket_set)
 224       Error(ERR_EXIT, "SDLNet_AllocSocketSet() failed: %s"), SDLNet_GetError();
 225
 226     udp = SDLNet_UDP_Open(0);
 227     if(!udp)
 228       Error(ERR_EXIT, "SDLNet_UDP_Open() failed: %s", SDLNet_GetError());
 229
 230     if (SDLNet_UDP_AddSocket(udp_socket_set, udp) == -1)
 231       Error(ERR_EXIT_NETWORK_SERVER, "SDLNet_TCP_AddSocket() failed: %s"),
 232         SDLNet_GetError();
 233
 234     char *data_ptr = "network server UDB broadcast";
 235     int data_len = strlen(data_ptr) + 1;
 236     IPaddress ip_address;
 237
 238     SDLNet_Write32(0xffffffff, &ip_address.host);       // 255.255.255.255
 239     SDLNet_Write16(port,       &ip_address.port);
 240
 241     UDPpacket packet =
 242     {
 243       -1,
 244       (Uint8 *)data_ptr,
 245       data_len,
 246       data_len,
 247       0,
 248       ip_address
 249     };
 250
 251     SDLNet_UDP_Send(udp, -1, &packet);
 252
 253     DrawNetworkText("Looking for nearby network server ...");
 254
 255     // wait for any nearby network server to answer UDP broadcast
 256     for (i = 0; i < 5; i++)
 257     {
 258       if (SDLNet_CheckSockets(udp_socket_set, 0) == 1)
 259       {
 260         int num_packets = SDLNet_UDP_Recv(udp, &packet);
 261
 262         if (num_packets == 1)
 263         {
 264           char message[100];
 265
 266           server_host = SDLNet_Read32(&packet.address.host);
 267
 268           sprintf(message, "Network server found at %d.%d.%d.%d!",
 269                   (server_host >> 24) & 0xff,
 270                   (server_host >> 16) & 0xff,
 271                   (server_host >>  8) & 0xff,
 272                   (server_host >>  0) & 0xff);
 273
 274           DrawNetworkText_Success(message);
 275         }
 276         else
 277         {
 278           DrawNetworkText_Failed("No answer from network server!");
 279         }
 280
 281         break;
 282       }
 283       else
 284       {
 285         Delay_WithScreenUpdates(100);
 286       }
 287     }
 288
 289     if (server_host == 0)
 290       DrawNetworkText_Failed("No nearby network server found!");
 291   }
 292
 293   rfds = SDLNet_AllocSocketSet(1);
 294
 295   if (hostname)
 296   {
 297     char message[100];
 298
 299     SDLNet_ResolveHost(&ip, hostname, port);
 300
 301     if (ip.host == INADDR_NONE)
 302     {
 303       sprintf(message, "Failed to resolve network server hostname '%s'!",
 304               hostname);
 305
 306       DrawNetworkText_Failed(message);
 307
 308       return FALSE;
 309     }
 310     else
 311     {
 312       server_host = SDLNet_Read32(&ip.host);
 313     }
 314
 315     sprintf(message, "Connecting to network server host %s ...", hostname);
 316
 317     DrawNetworkText(message);
 318   }
 319   else
 320   {
 321     // if no hostname was given and no network server was auto-detected in the
 322     // local network, try to connect to a network server at the local host
 323     if (server_host == 0)
 324     {
 325       server_host = 0x7f000001;                 // 127.0.0.1
 326
 327       DrawNetworkText("Looking for local network server ...");
 328     }
 329     else
 330     {
 331       DrawNetworkText("Connecting to network server ...");
 332     }
 333
 334     SDLNet_Write32(server_host, &ip.host);
 335     SDLNet_Write16(port,        &ip.port);
 336   }
 337
 338   Error(ERR_DEBUG, "trying to connect to network server at %d.%d.%d.%d ...",
 339         (server_host >> 24) & 0xff,
 340         (server_host >> 16) & 0xff,
 341         (server_host >>  8) & 0xff,
 342         (server_host >>  0) & 0xff);
 343
 344   sfd = SDLNet_TCP_Open(&ip);
 345
 346   if (sfd)
 347   {
 348     SDLNet_TCP_AddSocket(rfds, sfd);
 349
 350     DrawNetworkText_Success("Successfully connected!");
 351
 352     return TRUE;
 353   }
 354   else
 355   {
 356     if (hostname)
 357       DrawNetworkText_Failed("Failed to connect to network server!");
 358     else
 359       DrawNetworkText_Failed("No local network server found!");
 360
 361     printf("SDLNet_TCP_Open(): %s\n", SDLNet_GetError());
 362   }
 363
 364   if (hostname)                 // connect to specified server failed
 365     return FALSE;
 366
 367   DrawNetworkText("Starting new local network server ...");
 368
 369   StartNetworkServer(port);
 370
 371   // wait for server to start up and try connecting several times
 372   for (i = 0; i < 30; i++)
 373   {
 374     if ((sfd = SDLNet_TCP_Open(&ip)))           // connected
 375     {
 376       DrawNetworkText_Success("Successfully connected to newly started network server!");
 377
 378       SDLNet_TCP_AddSocket(rfds, sfd);
 379
 380       return TRUE;
 381     }
 382
 383     Delay_WithScreenUpdates(100);
 384   }
 385
 386   DrawNetworkText_Failed("Failed to connect to newly started network server!");
 387
 388   // when reaching this point, connect to newly started server has failed
 389   return FALSE;
 390 }
 391
 392 void SendToServer_PlayerName(char *player_name)
 393 {
 394   initNetworkBufferForWriting(write_buffer, OP_PLAYER_NAME, 0);
 395
 396   putNetworkBufferString(write_buffer, player_name);
 397
 398   SendNetworkBufferToServer(write_buffer);
 399
 400   Error(ERR_NETWORK_CLIENT, "you set your player name to \"%s\"", player_name);
 401 }
 402
 403 void SendToServer_ProtocolVersion(void)
 404 {
 405   initNetworkBufferForWriting(write_buffer, OP_PROTOCOL_VERSION, 0);
 406
 407   putNetworkBuffer8BitInteger(write_buffer, PROTOCOL_VERSION_MAJOR);
 408   putNetworkBuffer8BitInteger(write_buffer, PROTOCOL_VERSION_MINOR);
 409   putNetworkBuffer8BitInteger(write_buffer, PROTOCOL_VERSION_PATCH);
 410
 411   SendNetworkBufferToServer(write_buffer);
 412 }
 413
 414 void SendToServer_NrWanted(int nr_wanted)
 415 {
 416   initNetworkBufferForWriting(write_buffer, OP_NUMBER_WANTED, 0);
 417
 418   putNetworkBuffer8BitInteger(write_buffer, nr_wanted);
 419
 420   SendNetworkBufferToServer(write_buffer);
 421 }
 422
 423 void SendToServer_LevelFile(void)
 424 {
 425   initNetworkBufferForWriting(write_buffer, OP_LEVEL_FILE, 0);
 426
 427   putNetworkBufferString(      write_buffer, leveldir_current->identifier);
 428   putNetworkBuffer16BitInteger(write_buffer, level.file_info.nr);
 429   putNetworkBuffer8BitInteger( write_buffer, level.file_info.type);
 430   putNetworkBuffer8BitInteger( write_buffer, level.file_info.packed);
 431   putNetworkBufferString(      write_buffer, level.file_info.basename);
 432   putNetworkBufferFile(        write_buffer, level.file_info.filename);
 433   putNetworkBuffer8BitInteger( write_buffer, level.use_custom_template);
 434
 435   if (level.use_custom_template)
 436   {
 437     putNetworkBufferString(write_buffer, level_template.file_info.basename);
 438     putNetworkBufferFile(  write_buffer, level_template.file_info.filename);
 439   }
 440
 441   SendNetworkBufferToServer(write_buffer);
 442
 443   setString(&network_level.leveldir_identifier, leveldir_current->identifier);
 444
 445   // the sending client does not use network level files (but the real ones)
 446   network_level.use_network_level_files = FALSE;
 447
 448 #if 0
 449   printf("::: '%s'\n", leveldir_current->identifier);
 450   printf("::: '%d'\n", level.file_info.nr);
 451   printf("::: '%d'\n", level.file_info.type);
 452   printf("::: '%d'\n", level.file_info.packed);
 453   printf("::: '%s'\n", level.file_info.basename);
 454   printf("::: '%s'\n", level.file_info.filename);
 455
 456   if (level.use_custom_template)
 457     printf("::: '%s'\n", level_template.file_info.filename);
 458 #endif
 459 }
 460
 461 void SendToServer_StartPlaying(void)
 462 {
 463   unsigned int new_random_seed = InitRND(level.random_seed);
 464
 465   initNetworkBufferForWriting(write_buffer, OP_START_PLAYING, 0);
 466
 467   putNetworkBufferString(      write_buffer, leveldir_current->identifier);
 468   putNetworkBuffer16BitInteger(write_buffer, level_nr);
 469   putNetworkBuffer32BitInteger(write_buffer, new_random_seed);
 470
 471   SendNetworkBufferToServer(write_buffer);
 472 }
 473
 474 void SendToServer_PausePlaying(void)
 475 {
 476   initNetworkBufferForWriting(write_buffer, OP_PAUSE_PLAYING, 0);
 477
 478   SendNetworkBufferToServer(write_buffer);
 479 }
 480
 481 void SendToServer_ContinuePlaying(void)
 482 {
 483   initNetworkBufferForWriting(write_buffer, OP_CONTINUE_PLAYING, 0);
 484
 485   SendNetworkBufferToServer(write_buffer);
 486 }
 487
 488 void SendToServer_StopPlaying(int cause_for_stopping)
 489 {
 490   initNetworkBufferForWriting(write_buffer, OP_STOP_PLAYING, 0);
 491
 492   putNetworkBuffer8BitInteger(write_buffer, cause_for_stopping);
 493
 494   SendNetworkBufferToServer(write_buffer);
 495 }
 496
 497 void SendToServer_MovePlayer(byte player_action)
 498 {
 499   initNetworkBufferForWriting(write_buffer, OP_MOVE_PLAYER, 0);
 500
 501   putNetworkBuffer8BitInteger(write_buffer, player_action);
 502
 503   SendNetworkBufferToServer(write_buffer);
 504 }
 505
 506 static void Handle_OP_BAD_PROTOCOL_VERSION(void)
 507 {
 508   int protocol_version_major = getNetworkBuffer8BitInteger(read_buffer);
 509   int protocol_version_minor = getNetworkBuffer8BitInteger(read_buffer);
 510
 511   Error(ERR_WARN, "protocol version mismatch");
 512   Error(ERR_WARN, "server expects %d.%d.x instead of %d.%d.%d",
 513         protocol_version_major,
 514         protocol_version_minor,
 515         PROTOCOL_VERSION_MAJOR,
 516         PROTOCOL_VERSION_MINOR,
 517         PROTOCOL_VERSION_PATCH);
 518
 519   sprintf(stop_network_client_message, "Network protocol version mismatch! Server expects version %d.%d.x instead of %d.%d.%d!",
 520           protocol_version_major,
 521           protocol_version_minor,
 522           PROTOCOL_VERSION_MAJOR,
 523           PROTOCOL_VERSION_MINOR,
 524           PROTOCOL_VERSION_PATCH);
 525
 526   stop_network_client = TRUE;
 527 }
 528
 529 static void Handle_OP_YOUR_NUMBER(void)
 530 {
 531   int old_client_nr = getNetworkBuffer8BitInteger(read_buffer);
 532   int new_client_nr = getNetworkBuffer8BitInteger(read_buffer);
 533   int new_index_nr = new_client_nr - 1;
 534   struct PlayerInfo *old_local_player = local_player;
 535   struct PlayerInfo *new_local_player = &stored_player[new_index_nr];
 536
 537   printf("OP_YOUR_NUMBER: %d\n", old_client_nr);
 538   first_player.nr = new_client_nr;
 539
 540   if (old_local_player != new_local_player)
 541   {
 542     // set relevant player settings and change to new player
 543
 544     local_player = new_local_player;
 545
 546     old_local_player->connected_locally = FALSE;
 547     new_local_player->connected_locally = TRUE;
 548
 549     old_local_player->connected_network = FALSE;
 550     new_local_player->connected_network = TRUE;
 551   }
 552
 553   if (first_player.nr > MAX_PLAYERS)
 554     Error(ERR_EXIT, "sorry, more than %d players not allowed", MAX_PLAYERS);
 555
 556   Error(ERR_NETWORK_CLIENT, "you get client # %d", new_client_nr);
 557
 558   stored_player[new_index_nr].connected_network = TRUE;
 559 }
 560
 561 static void Handle_OP_NUMBER_WANTED(void)
 562 {
 563   int old_client_nr    = getNetworkBuffer8BitInteger(read_buffer);
 564   int client_nr_wanted = getNetworkBuffer8BitInteger(read_buffer);
 565   int new_client_nr    = getNetworkBuffer8BitInteger(read_buffer);
 566   int old_index_nr = old_client_nr - 1;
 567   int new_index_nr = new_client_nr - 1;
 568   int index_nr_wanted = client_nr_wanted - 1;
 569   struct PlayerInfo *old_player = &stored_player[old_index_nr];
 570   struct PlayerInfo *new_player = &stored_player[new_index_nr];
 571
 572   printf("OP_NUMBER_WANTED: %d\n", old_client_nr);
 573
 574   if (new_client_nr == client_nr_wanted)        // switching succeeded
 575   {
 576     struct NetworkClientPlayerInfo *player;
 577
 578     if (old_client_nr != client_nr_wanted)      // client's nr has changed
 579       Error(ERR_NETWORK_CLIENT, "client %d switches to # %d",
 580             old_client_nr, new_client_nr);
 581     else if (old_client_nr == first_player.nr)  // local player keeps his nr
 582       Error(ERR_NETWORK_CLIENT, "keeping client # %d", new_client_nr);
 583
 584     if (old_client_nr != new_client_nr)
 585     {
 586       // set relevant player settings and change to new player
 587
 588       old_player->connected_network = FALSE;
 589       new_player->connected_network = TRUE;
 590     }
 591
 592     player = getNetworkPlayer(old_client_nr);
 593     player->nr = new_client_nr;
 594
 595     if (old_player == local_player)             // local player switched
 596     {
 597       local_player = new_player;
 598
 599       old_player->connected_locally = FALSE;
 600       new_player->connected_locally = TRUE;
 601     }
 602   }
 603   else if (old_client_nr == first_player.nr)    // failed -- local player?
 604   {
 605     char request[100];
 606
 607     sprintf(request, "Sorry! Player %d already exists! You are player %d!",
 608             index_nr_wanted + 1, new_index_nr + 1);
 609
 610     Request(request, REQ_CONFIRM);
 611
 612     Error(ERR_NETWORK_CLIENT, "cannot switch -- you keep client # %d",
 613           new_client_nr);
 614   }
 615
 616   if (game_status == GAME_MODE_MAIN)
 617     DrawNetworkPlayers();
 618 }
 619
 620 static void Handle_OP_PLAYER_NAME(void)
 621 {
 622   int player_nr = getNetworkBuffer8BitInteger(read_buffer);
 623   char *player_name = getNetworkBufferString(read_buffer);
 624   struct NetworkClientPlayerInfo *player = getNetworkPlayer(player_nr);
 625
 626   printf("OP_PLAYER_NAME: %d\n", player_nr);
 627
 628   strncpy(player->name, player_name, MAX_PLAYER_NAME_LEN);
 629   player->name[MAX_PLAYER_NAME_LEN] = '\0';
 630
 631   Error(ERR_NETWORK_CLIENT, "client %d calls itself \"%s\"",
 632         player_nr, player->name);
 633 }
 634
 635 static void Handle_OP_PLAYER_CONNECTED(void)
 636 {
 637   struct NetworkClientPlayerInfo *player, *last_player = NULL;
 638   int new_client_nr = getNetworkBuffer8BitInteger(read_buffer);
 639   int new_index_nr = new_client_nr - 1;
 640
 641   printf("OP_PLAYER_CONNECTED: %d\n", new_client_nr);
 642   Error(ERR_NETWORK_CLIENT, "new client %d connected", new_client_nr);
 643
 644   for (player = &first_player; player; player = player->next)
 645   {
 646     if (player->nr == new_client_nr)
 647       Error(ERR_EXIT, "multiplayer server sent duplicate player id");
 648
 649     last_player = player;
 650   }
 651
 652   last_player->next = player =
 653     checked_malloc(sizeof(struct NetworkClientPlayerInfo));
 654   player->nr = new_client_nr;
 655   player->name[0] = '\0';
 656   player->next = NULL;
 657
 658   stored_player[new_index_nr].connected_network = TRUE;
 659 }
 660
 661 static void Handle_OP_PLAYER_DISCONNECTED(void)
 662 {
 663   struct NetworkClientPlayerInfo *player, *player_disconnected;
 664   int player_nr = getNetworkBuffer8BitInteger(read_buffer);
 665   int index_nr = player_nr - 1;
 666
 667   printf("OP_PLAYER_DISCONNECTED: %d\n", player_nr);
 668   player_disconnected = getNetworkPlayer(player_nr);
 669   Error(ERR_NETWORK_CLIENT, "client %d (%s) disconnected",
 670         player_nr, getNetworkPlayerName(player_nr));
 671
 672   for (player = &first_player; player; player = player->next)
 673     if (player->next == player_disconnected)
 674       player->next = player_disconnected->next;
 675   free(player_disconnected);
 676
 677   stored_player[index_nr].connected_locally = FALSE;
 678   stored_player[index_nr].connected_network = FALSE;
 679
 680   if (game_status == GAME_MODE_PLAYING)
 681   {
 682     char message[100];
 683
 684     sprintf(message, "Player %d left network server! Network game stopped!",
 685             player_nr);
 686
 687     Request(message, REQ_CONFIRM | REQ_STAY_CLOSED);
 688
 689     SetGameStatus(GAME_MODE_MAIN);
 690
 691     DrawMainMenu();
 692   }
 693   else if (game_status == GAME_MODE_MAIN)
 694   {
 695     DrawNetworkPlayers();
 696   }
 697 }
 698
 699 static void Handle_OP_START_PLAYING(void)
 700 {
 701   int player_nr = getNetworkBuffer8BitInteger(read_buffer);
 702   char *new_leveldir_identifier = getNetworkBufferString(read_buffer);
 703   int new_level_nr = getNetworkBuffer16BitInteger(read_buffer);
 704   unsigned int new_random_seed = getNetworkBuffer32BitInteger(read_buffer);
 705
 706   if (!strEqual(new_leveldir_identifier, network_level.leveldir_identifier))
 707   {
 708     Error(ERR_WARN, "no such level identifier: '%s'", new_leveldir_identifier);
 709
 710     stop_network_game = TRUE;
 711
 712     return;
 713   }
 714
 715   printf("OP_START_PLAYING: %d\n", player_nr);
 716   Error(ERR_NETWORK_CLIENT,
 717         "client %d starts game [level %d from level identifier '%s']\n",
 718         player_nr, new_level_nr, new_leveldir_identifier);
 719
 720   LevelDirTree *new_leveldir =
 721     getTreeInfoFromIdentifier(leveldir_first, new_leveldir_identifier);
 722
 723   if (new_leveldir != NULL)
 724   {
 725     leveldir_current = new_leveldir;
 726     level_nr = new_level_nr;
 727   }
 728
 729   // needed if level set of network game changed graphics, sounds or music
 730   ReloadCustomArtwork(0);
 731
 732   TapeErase();
 733
 734   if (network_level.use_network_level_files)
 735     LoadNetworkLevel(&network_level);
 736   else
 737     LoadLevel(level_nr);
 738
 739   StartGameActions(FALSE, setup.autorecord, new_random_seed);
 740 }
 741
 742 static void Handle_OP_PAUSE_PLAYING(void)
 743 {
 744   int player_nr = getNetworkBuffer8BitInteger(read_buffer);
 745
 746   printf("OP_PAUSE_PLAYING: %d\n", player_nr);
 747   Error(ERR_NETWORK_CLIENT, "client %d pauses game", player_nr);
 748
 749   if (game_status == GAME_MODE_PLAYING)
 750   {
 751     tape.pausing = TRUE;
 752     DrawVideoDisplay(VIDEO_STATE_PAUSE_ON, 0);
 753   }
 754 }
 755
 756 static void Handle_OP_CONTINUE_PLAYING(void)
 757 {
 758   int player_nr = getNetworkBuffer8BitInteger(read_buffer);
 759
 760   printf("OP_CONTINUE_PLAYING: %d\n", player_nr);
 761   Error(ERR_NETWORK_CLIENT, "client %d continues game", player_nr);
 762
 763   if (game_status == GAME_MODE_PLAYING)
 764   {
 765     tape.pausing = FALSE;
 766     DrawVideoDisplay(VIDEO_STATE_PAUSE_OFF, 0);
 767   }
 768 }
 769
 770 static void Handle_OP_STOP_PLAYING(void)
 771 {
 772   int client_nr = getNetworkBuffer8BitInteger(read_buffer);
 773   int cause_for_stopping = getNetworkBuffer8BitInteger(read_buffer);
 774
 775   printf("OP_STOP_PLAYING: %d [%d]\n", client_nr, cause_for_stopping);
 776   Error(ERR_NETWORK_CLIENT, "client %d stops game [%d]",
 777         client_nr, cause_for_stopping);
 778
 779   if (game_status == GAME_MODE_PLAYING)
 780   {
 781     int index_nr = client_nr - 1;
 782     struct PlayerInfo *client_player = &stored_player[index_nr];
 783     boolean stopped_by_remote_player = (!client_player->connected_locally);
 784     char message[100];
 785
 786     if (cause_for_stopping == NETWORK_STOP_BY_PLAYER)
 787       sprintf(message, "Network game stopped by player %d!", client_nr);
 788     else
 789       sprintf(message, (cause_for_stopping == NETWORK_STOP_BY_ERROR ?
 790                         "Network game stopped due to internal error!" :
 791                         "Network game stopped!"));
 792
 793     if (cause_for_stopping != NETWORK_STOP_BY_PLAYER ||
 794         stopped_by_remote_player)
 795       Request(message, REQ_CONFIRM | REQ_STAY_CLOSED);
 796
 797     SetGameStatus(GAME_MODE_MAIN);
 798
 799     DrawMainMenu();
 800   }
 801 }
 802
 803 static void Handle_OP_MOVE_PLAYER(void)
 804 {
 805   int player_nr = getNetworkBuffer8BitInteger(read_buffer);
 806   int server_frame_counter = getNetworkBuffer32BitInteger(read_buffer);
 807   int i;
 808
 809   if (!network_playing)
 810     return;
 811
 812   if (server_frame_counter != FrameCounter)
 813   {
 814     Error(ERR_INFO, "frame counters of client %d and server out of sync",
 815           player_nr);
 816     Error(ERR_INFO, "frame counter of client is %d", FrameCounter);
 817     Error(ERR_INFO, "frame counter of server is %d", server_frame_counter);
 818     Error(ERR_INFO, "this should not happen -- please debug");
 819
 820     stop_network_game = TRUE;
 821
 822     return;
 823   }
 824
 825   // copy valid player actions (will be set to 0 for not connected players)
 826   for (i = 0; i < MAX_PLAYERS; i++)
 827     stored_player[i].effective_action =
 828       getNetworkBuffer8BitInteger(read_buffer);
 829
 830   network_player_action_received = TRUE;
 831 }
 832
 833 static void Handle_OP_BROADCAST_MESSAGE(void)
 834 {
 835   int player_nr = getNetworkBuffer8BitInteger(read_buffer);
 836
 837   printf("OP_BROADCAST_MESSAGE: %d\n", player_nr);
 838   Error(ERR_NETWORK_CLIENT, "client %d sends message", player_nr);
 839 }
 840
 841 static void Handle_OP_LEVEL_FILE(void)
 842 {
 843   int player_nr = getNetworkBuffer8BitInteger(read_buffer);
 844   char *leveldir_identifier;
 845   char *network_level_dir;
 846   struct LevelFileInfo *file_info = &network_level.file_info;
 847   struct LevelFileInfo *tmpl_info = &network_level.tmpl_info;
 848   boolean use_custom_template;
 849
 850   setString(&network_level.leveldir_identifier, NULL);
 851   setString(&network_level.file_info.basename,  NULL);
 852   setString(&network_level.file_info.filename,  NULL);
 853   setString(&network_level.tmpl_info.basename,  NULL);
 854   setString(&network_level.tmpl_info.filename,  NULL);
 855
 856   printf("OP_LEVEL_FILE: %d\n", player_nr);
 857
 858   leveldir_identifier = getStringCopy(getNetworkBufferString(read_buffer));
 859
 860   if (hasPathSeparator(leveldir_identifier))
 861     Error(ERR_EXIT, "protocol error: invalid filename from network client");
 862
 863   InitNetworkLevelDirectory(leveldir_identifier);
 864
 865   network_level_dir   = getNetworkLevelDir(leveldir_identifier);
 866
 867   file_info->nr       = getNetworkBuffer16BitInteger(read_buffer);
 868   file_info->type     = getNetworkBuffer8BitInteger(read_buffer);
 869   file_info->packed   = getNetworkBuffer8BitInteger(read_buffer);
 870   file_info->basename = getStringCopy(getNetworkBufferString(read_buffer));
 871   file_info->filename = getPath2(network_level_dir, file_info->basename);
 872
 873   if (hasPathSeparator(file_info->basename))
 874     Error(ERR_EXIT, "protocol error: invalid filename from network client");
 875
 876   getNetworkBufferFile(read_buffer, file_info->filename);
 877
 878   use_custom_template = getNetworkBuffer8BitInteger(read_buffer);
 879   if (use_custom_template)
 880   {
 881     *tmpl_info = *file_info;
 882
 883     tmpl_info->basename = getStringCopy(getNetworkBufferString(read_buffer));
 884     tmpl_info->filename = getPath2(network_level_dir, tmpl_info->basename);
 885
 886     if (hasPathSeparator(tmpl_info->basename))
 887       Error(ERR_EXIT, "protocol error: invalid filename from network client");
 888
 889     getNetworkBufferFile(read_buffer, tmpl_info->filename);
 890   }
 891
 892   network_level.leveldir_identifier = leveldir_identifier;
 893   network_level.use_custom_template = use_custom_template;
 894
 895   // the receiving client(s) use(s) the transferred network level files
 896   network_level.use_network_level_files = TRUE;
 897
 898 #if 0
 899   printf("::: '%s'\n", leveldir_identifier);
 900   printf("::: '%d'\n", file_info->nr);
 901   printf("::: '%d'\n", file_info->type);
 902   printf("::: '%d'\n", file_info->packed);
 903   printf("::: '%s'\n", file_info->basename);
 904   printf("::: '%s'\n", file_info->filename);
 905
 906   if (use_custom_template)
 907     printf("::: '%s'\n", tmpl_info->filename);
 908 #endif
 909 }
 910
 911 static void HandleNetworkingMessage(void)
 912 {
 913   stop_network_game = FALSE;
 914
 915   initNetworkBufferForReading(read_buffer);
 916
 917   int message_type = getNetworkBuffer8BitInteger(read_buffer);
 918
 919   switch (message_type)
 920   {
 921     case OP_BAD_PROTOCOL_VERSION:
 922       Handle_OP_BAD_PROTOCOL_VERSION();
 923       break;
 924
 925     case OP_YOUR_NUMBER:
 926       Handle_OP_YOUR_NUMBER();
 927       break;
 928
 929     case OP_NUMBER_WANTED:
 930       Handle_OP_NUMBER_WANTED();
 931       break;
 932
 933     case OP_PLAYER_NAME:
 934       Handle_OP_PLAYER_NAME();
 935       break;
 936
 937     case OP_PLAYER_CONNECTED:
 938       Handle_OP_PLAYER_CONNECTED();
 939       break;
 940
 941     case OP_PLAYER_DISCONNECTED:
 942       Handle_OP_PLAYER_DISCONNECTED();
 943       break;
 944
 945     case OP_START_PLAYING:
 946       Handle_OP_START_PLAYING();
 947       break;
 948
 949     case OP_PAUSE_PLAYING:
 950       Handle_OP_PAUSE_PLAYING();
 951       break;
 952
 953     case OP_CONTINUE_PLAYING:
 954       Handle_OP_CONTINUE_PLAYING();
 955       break;
 956
 957     case OP_STOP_PLAYING:
 958       Handle_OP_STOP_PLAYING();
 959       break;
 960
 961     case OP_MOVE_PLAYER:
 962       Handle_OP_MOVE_PLAYER();
 963       break;
 964
 965     case OP_BROADCAST_MESSAGE:
 966       Handle_OP_BROADCAST_MESSAGE();
 967       break;
 968
 969     case OP_LEVEL_FILE:
 970       Handle_OP_LEVEL_FILE();
 971       break;
 972
 973     default:
 974       if (options.verbose)
 975         Error(ERR_NETWORK_CLIENT,
 976               "unknown opcode %d from server", message_type);
 977   }
 978
 979   fflush(stdout);
 980
 981   // in case of internal error, stop network game
 982   if (stop_network_game)
 983     SendToServer_StopPlaying(NETWORK_STOP_BY_ERROR);
 984 }
 985
 986 static char *HandleNetworkingPackets(void)
 987 {
 988   while (1)
 989   {
 990     // ---------- check network server for activity ----------
 991
 992     int num_active_sockets = SDLNet_CheckSockets(rfds, 0);
 993
 994     if (num_active_sockets < 0)
 995       return "Error checking network sockets!";
 996
 997     if (num_active_sockets == 0)
 998       break;    // no active sockets, stop here
 999
1000     // ---------- read packets from network server ----------
1001
1002     initNetworkBufferForReceiving(read_buffer);
1003
1004     int num_bytes = receiveNetworkBufferPacket(read_buffer, sfd);
1005
1006     if (num_bytes < 0)
1007       return "Error reading from network server!";
1008
1009     if (num_bytes == 0)
1010       return "Connection to network server lost!";
1011
1012     HandleNetworkingMessage();
1013
1014     if (stop_network_client)
1015       return stop_network_client_message;
1016   }
1017
1018   return NULL;
1019 }
1020
1021 static void FreeNetworkClientPlayerInfo(struct NetworkClientPlayerInfo *player)
1022 {
1023   if (player == NULL)
1024     return;
1025
1026   if (player->next)
1027     FreeNetworkClientPlayerInfo(player->next);
1028
1029   checked_free(player);
1030 }
1031
1032 static void HandleNetworkingDisconnect(void)
1033 {
1034   int i;
1035
1036   SDLNet_TCP_DelSocket(rfds, sfd);
1037   SDLNet_TCP_Close(sfd);
1038
1039   network_playing = FALSE;
1040
1041   network.enabled = FALSE;
1042   network.connected = FALSE;
1043
1044   setup.network_mode = FALSE;
1045
1046   for (i = 0; i < MAX_PLAYERS; i++)
1047     stored_player[i].connected_network = FALSE;
1048
1049   FreeNetworkClientPlayerInfo(first_player.next);
1050
1051   first_player.nr = 0;
1052   first_player.next = NULL;
1053 }
1054
1055 void HandleNetworking(void)
1056 {
1057   // do not handle any networking packets if request dialog is active
1058   if (game.request_active)
1059     return;
1060
1061   char *error_message = HandleNetworkingPackets();
1062
1063   if (error_message != NULL)
1064   {
1065     HandleNetworkingDisconnect();
1066
1067     if (game_status == GAME_MODE_PLAYING)
1068     {
1069       Request(error_message, REQ_CONFIRM | REQ_STAY_CLOSED);
1070
1071       SetGameStatus(GAME_MODE_MAIN);
1072
1073       DrawMainMenu();
1074     }
1075     else
1076     {
1077       Request(error_message, REQ_CONFIRM);
1078
1079       if (game_status == GAME_MODE_MAIN)
1080         ClearNetworkPlayers();
1081     }
1082   }
1083 }
1084
1085 void DisconnectFromNetworkServer(void)
1086 {
1087   DrawNetworkText_Title("Terminating Network");
1088   DrawNetworkText("Disconnecting from network server ...");
1089
1090   HandleNetworkingDisconnect();
1091
1092   DrawNetworkText_Success("Successfully disconnected!");
1093 }