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