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 "libgame/platform.h"
  13
  14 #if defined(NETWORK_AVALIABLE)
  15
  16 #include <signal.h>
  17 #include <sys/time.h>
  18
  19 #include "main.h"
  20
  21 #include "libgame/libgame.h"
  22
  23 #include "network.h"
  24 #include "netserv.h"
  25 #include "game.h"
  26 #include "tape.h"
  27 #include "files.h"
  28 #include "tools.h"
  29 #include "screens.h"
  30
  31 struct NetworkClientPlayerInfo
  32 {
  33   byte nr;
  34   char name[MAX_PLAYER_NAME_LEN + 1];
  35   struct NetworkClientPlayerInfo *next;
  36 };
  37
  38 static struct NetworkClientPlayerInfo first_player =
  39 {
  40   0,
  41   EMPTY_PLAYER_NAME,
  42   NULL
  43 };
  44
  45 /* server stuff */
  46
  47 static TCPsocket sfd;           /* server socket */
  48 static SDLNet_SocketSet rfds;   /* socket set */
  49
  50 static byte realbuffer[512];
  51 static byte readbuffer[MAX_BUFFER_SIZE], writbuffer[MAX_BUFFER_SIZE];
  52 static byte *buffer = realbuffer + 4;
  53 static int nread = 0, nwrite = 0;
  54 static boolean stop_network_game = FALSE;
  55
  56 static void SendBufferToServer(int size)
  57 {
  58   if (!options.network)
  59     return;
  60
  61   realbuffer[0] = realbuffer[1] = realbuffer[2] = 0;
  62   realbuffer[3] = (byte)size;
  63   buffer[0] = 0;
  64
  65   if (nwrite + 4 + size >= MAX_BUFFER_SIZE)
  66     Error(ERR_EXIT, "internal error: network send buffer overflow");
  67
  68   memcpy(writbuffer + nwrite, realbuffer, 4 + size);
  69   nwrite += 4 + size;
  70
  71   /* directly send the buffer to the network server */
  72   SDLNet_TCP_Send(sfd, writbuffer, nwrite);
  73   nwrite = 0;
  74 }
  75
  76 struct NetworkClientPlayerInfo *getNetworkPlayer(int player_nr)
  77 {
  78   struct NetworkClientPlayerInfo *player = NULL;
  79
  80   for (player = &first_player; player; player = player->next)
  81     if (player->nr == player_nr)
  82       break;
  83
  84   if (player == NULL)   /* should not happen */
  85     Error(ERR_EXIT, "protocol error: reference to non-existing player %d",
  86           player_nr);
  87
  88   return player;
  89 }
  90
  91 char *getNetworkPlayerName(int player_nr)
  92 {
  93   struct NetworkClientPlayerInfo *player;
  94
  95   if (player_nr == 0)
  96     return("the network game server");
  97   else if (player_nr == first_player.nr)
  98     return("you");
  99   else
 100     for (player = &first_player; player; player = player->next)
 101       if (player->nr == player_nr && player->name && strlen(player->name))
 102         return(player->name);
 103
 104   return(EMPTY_PLAYER_NAME);
 105 }
 106
 107 static void StartNetworkServer(int port)
 108 {
 109   static int p;
 110
 111   p = port;
 112 #if defined(TARGET_SDL2)
 113   server_thread = SDL_CreateThread(NetworkServerThread,
 114                                    "NetworkServerThread", &p);
 115 #else
 116   server_thread = SDL_CreateThread(NetworkServerThread, &p);
 117 #endif
 118   network_server = TRUE;
 119 }
 120
 121 boolean ConnectToServer(char *hostname, int port)
 122 {
 123   IPaddress ip;
 124   int i;
 125
 126   if (port == 0)
 127     port = DEFAULT_SERVER_PORT;
 128
 129   rfds = SDLNet_AllocSocketSet(1);
 130
 131   if (hostname)
 132   {
 133     SDLNet_ResolveHost(&ip, hostname, port);
 134     if (ip.host == INADDR_NONE)
 135       Error(ERR_EXIT, "cannot locate host '%s'", hostname);
 136   }
 137   else
 138   {
 139     SDLNet_Write32(0x7f000001, &ip.host);       /* 127.0.0.1 */
 140     SDLNet_Write16(port, &ip.port);
 141   }
 142
 143   sfd = SDLNet_TCP_Open(&ip);
 144
 145   if (sfd)
 146   {
 147     SDLNet_TCP_AddSocket(rfds, sfd);
 148     return TRUE;
 149   }
 150   else
 151   {
 152     printf("SDLNet_TCP_Open(): %s\n", SDLNet_GetError());
 153   }
 154
 155   if (hostname)                 /* connect to specified server failed */
 156     return FALSE;
 157
 158   printf("No rocksndiamonds server on localhost -- starting up one ...\n");
 159   StartNetworkServer(port);
 160
 161   /* wait for server to start up and try connecting several times */
 162   for (i = 0; i < 6; i++)
 163   {
 164     Delay(500);                 /* wait 500 ms == 0.5 seconds */
 165
 166     if ((sfd = SDLNet_TCP_Open(&ip)))           /* connected */
 167     {
 168       SDLNet_TCP_AddSocket(rfds, sfd);
 169       return TRUE;
 170     }
 171   }
 172
 173   /* when reaching this point, connect to newly started server has failed */
 174   return FALSE;
 175 }
 176
 177 void SendToServer_PlayerName(char *player_name)
 178 {
 179   int len_player_name = strlen(player_name);
 180
 181   buffer[1] = OP_PLAYER_NAME;
 182   memcpy(&buffer[2], player_name, len_player_name);
 183   SendBufferToServer(2 + len_player_name);
 184   Error(ERR_NETWORK_CLIENT, "you set your player name to \"%s\"", player_name);
 185 }
 186
 187 void SendToServer_ProtocolVersion()
 188 {
 189   buffer[1] = OP_PROTOCOL_VERSION;
 190   buffer[2] = PROTOCOL_VERSION_1;
 191   buffer[3] = PROTOCOL_VERSION_2;
 192   buffer[4] = PROTOCOL_VERSION_3;
 193
 194   SendBufferToServer(5);
 195 }
 196
 197 void SendToServer_NrWanted(int nr_wanted)
 198 {
 199   buffer[1] = OP_NUMBER_WANTED;
 200   buffer[2] = nr_wanted;
 201
 202   SendBufferToServer(3);
 203 }
 204
 205 void SendToServer_StartPlaying()
 206 {
 207   unsigned int new_random_seed = InitRND(level.random_seed);
 208
 209   int dummy = 0;                /* !!! HAS NO MEANING ANYMORE !!! */
 210                                 /* the name of the level must be enough */
 211
 212   buffer[1] = OP_START_PLAYING;
 213   buffer[2] = (byte)(level_nr >> 8);
 214   buffer[3] = (byte)(level_nr & 0xff);
 215   buffer[4] = (byte)(dummy >> 8);
 216   buffer[5] = (byte)(dummy & 0xff);
 217
 218   buffer[6] = (unsigned char)((new_random_seed >> 24) & 0xff);
 219   buffer[7] = (unsigned char)((new_random_seed >> 16) & 0xff);
 220   buffer[8] = (unsigned char)((new_random_seed >>  8) & 0xff);
 221   buffer[9] = (unsigned char)((new_random_seed >>  0) & 0xff);
 222
 223   strcpy((char *)&buffer[10], leveldir_current->identifier);
 224
 225   SendBufferToServer(10 + strlen(leveldir_current->identifier) + 1);
 226 }
 227
 228 void SendToServer_PausePlaying()
 229 {
 230   buffer[1] = OP_PAUSE_PLAYING;
 231
 232   SendBufferToServer(2);
 233 }
 234
 235 void SendToServer_ContinuePlaying()
 236 {
 237   buffer[1] = OP_CONTINUE_PLAYING;
 238
 239   SendBufferToServer(2);
 240 }
 241
 242 void SendToServer_StopPlaying(int cause_for_stopping)
 243 {
 244   buffer[1] = OP_STOP_PLAYING;
 245   buffer[2] = cause_for_stopping;
 246
 247   SendBufferToServer(3);
 248 }
 249
 250 void SendToServer_MovePlayer(byte player_action)
 251 {
 252   buffer[1] = OP_MOVE_PLAYER;
 253   buffer[2] = player_action;
 254
 255   SendBufferToServer(3);
 256 }
 257
 258 static void Handle_OP_BAD_PROTOCOL_VERSION()
 259 {
 260   Error(ERR_WARN, "protocol version mismatch");
 261   Error(ERR_EXIT, "server expects %d.%d.x instead of %d.%d.%d",
 262         buffer[2], buffer[3],
 263         PROTOCOL_VERSION_1, PROTOCOL_VERSION_2, PROTOCOL_VERSION_3);
 264 }
 265
 266 static void Handle_OP_YOUR_NUMBER()
 267 {
 268   int new_client_nr = buffer[2];
 269   int new_index_nr = new_client_nr - 1;
 270   struct PlayerInfo *old_local_player = local_player;
 271   struct PlayerInfo *new_local_player = &stored_player[new_index_nr];
 272
 273   printf("OP_YOUR_NUMBER: %d\n", buffer[0]);
 274   first_player.nr = new_client_nr;
 275
 276   if (old_local_player != new_local_player)
 277   {
 278     /* copy existing player settings and change to new player */
 279
 280     *new_local_player = *old_local_player;
 281     old_local_player->connected = FALSE;
 282     local_player = new_local_player;
 283   }
 284
 285   if (first_player.nr > MAX_PLAYERS)
 286     Error(ERR_EXIT, "sorry, more than %d players not allowed", MAX_PLAYERS);
 287
 288   Error(ERR_NETWORK_CLIENT, "you get client # %d", new_client_nr);
 289 }
 290
 291 static void Handle_OP_NUMBER_WANTED()
 292 {
 293   int client_nr_wanted = buffer[2];
 294   int old_client_nr = buffer[0];
 295   int new_client_nr = buffer[3];
 296   int old_index_nr = old_client_nr - 1;
 297   int new_index_nr = new_client_nr - 1;
 298   int index_nr_wanted = client_nr_wanted - 1;
 299   struct PlayerInfo *old_player = &stored_player[old_index_nr];
 300   struct PlayerInfo *new_player = &stored_player[new_index_nr];
 301
 302   printf("OP_NUMBER_WANTED: %d\n", buffer[0]);
 303
 304   if (new_client_nr == client_nr_wanted)        /* switching succeeded */
 305   {
 306     struct NetworkClientPlayerInfo *player;
 307
 308     if (old_client_nr != client_nr_wanted)      /* client's nr has changed */
 309       Error(ERR_NETWORK_CLIENT, "client %d switches to # %d",
 310             old_client_nr, new_client_nr);
 311     else if (old_client_nr == first_player.nr)  /* local player keeps his nr */
 312       Error(ERR_NETWORK_CLIENT, "keeping client # %d", new_client_nr);
 313
 314     if (old_client_nr != new_client_nr)
 315     {
 316       /* copy existing player settings and change to new player */
 317
 318       *new_player = *old_player;
 319       old_player->connected = FALSE;
 320     }
 321
 322     player = getNetworkPlayer(old_client_nr);
 323     player->nr = new_client_nr;
 324
 325     if (old_player == local_player)             /* local player switched */
 326       local_player = new_player;
 327   }
 328   else if (old_client_nr == first_player.nr)    /* failed -- local player? */
 329   {
 330     char request[100];
 331
 332     sprintf(request, "Sorry! Player %d already exists! You are player %d!",
 333             index_nr_wanted + 1, new_index_nr + 1);
 334
 335     Request(request, REQ_CONFIRM);
 336
 337     Error(ERR_NETWORK_CLIENT, "cannot switch -- you keep client # %d",
 338           new_client_nr);
 339   }
 340 }
 341
 342 static void Handle_OP_PLAYER_NAME(unsigned int len)
 343 {
 344   struct NetworkClientPlayerInfo *player;
 345   int player_nr = (int)buffer[0];
 346
 347   printf("OP_PLAYER_NAME: %d\n", player_nr);
 348   player = getNetworkPlayer(player_nr);
 349   buffer[len] = 0;
 350   Error(ERR_NETWORK_CLIENT, "client %d calls itself \"%s\"",
 351         buffer[0], &buffer[2]);
 352   strncpy(player->name, (char *)&buffer[2], MAX_PLAYER_NAME_LEN);
 353 }
 354
 355 static void Handle_OP_PLAYER_CONNECTED()
 356 {
 357   struct NetworkClientPlayerInfo *player, *last_player = NULL;
 358   int new_client_nr = (int)buffer[0];
 359   int new_index_nr = new_client_nr - 1;
 360
 361   printf("OP_PLAYER_CONNECTED: %d\n", new_client_nr);
 362   Error(ERR_NETWORK_CLIENT, "new client %d connected", new_client_nr);
 363
 364   for (player = &first_player; player; player = player->next)
 365   {
 366     if (player->nr == new_client_nr)
 367       Error(ERR_EXIT, "multiplayer server sent duplicate player id");
 368
 369     last_player = player;
 370   }
 371
 372   last_player->next = player =
 373     checked_malloc(sizeof(struct NetworkClientPlayerInfo));
 374   player->nr = new_client_nr;
 375   player->name[0] = '\0';
 376   player->next = NULL;
 377
 378   stored_player[new_index_nr].connected = TRUE;
 379 }
 380
 381 static void Handle_OP_PLAYER_DISCONNECTED()
 382 {
 383   struct NetworkClientPlayerInfo *player, *player_disconnected;
 384   int player_nr = (int)buffer[0];
 385
 386   printf("OP_PLAYER_DISCONNECTED: %d\n", player_nr);
 387   player_disconnected = getNetworkPlayer(player_nr);
 388   Error(ERR_NETWORK_CLIENT, "client %d (%s) disconnected",
 389         player_nr, getNetworkPlayerName(buffer[0]));
 390
 391   for (player = &first_player; player; player = player->next)
 392     if (player->next == player_disconnected)
 393       player->next = player_disconnected->next;
 394   free(player_disconnected);
 395 }
 396
 397 static void Handle_OP_START_PLAYING()
 398 {
 399   LevelDirTree *new_leveldir;
 400   int new_level_nr;
 401   unsigned int new_random_seed;
 402   char *new_leveldir_identifier;
 403
 404   new_level_nr = (buffer[2] << 8) + buffer[3];
 405   new_random_seed =
 406     (buffer[6] << 24) | (buffer[7] << 16) | (buffer[8] << 8) | (buffer[9]);
 407   new_leveldir_identifier = (char *)&buffer[10];
 408
 409   new_leveldir = getTreeInfoFromIdentifier(leveldir_first,
 410                                            new_leveldir_identifier);
 411   if (new_leveldir == NULL)
 412   {
 413     Error(ERR_WARN, "no such level identifier: '%s'", new_leveldir_identifier);
 414
 415     new_leveldir = leveldir_first;
 416     Error(ERR_WARN, "using default level set: '%s'", new_leveldir->identifier);
 417   }
 418
 419   printf("OP_START_PLAYING: %d\n", buffer[0]);
 420   Error(ERR_NETWORK_CLIENT,
 421         "client %d starts game [level %d from level identifier '%s']\n",
 422         buffer[0], new_level_nr, new_leveldir->identifier);
 423
 424   leveldir_current = new_leveldir;
 425   level_nr = new_level_nr;
 426
 427   TapeErase();
 428   LoadTape(level_nr);
 429   LoadLevel(level_nr);
 430
 431   StartGameActions(FALSE, setup.autorecord, new_random_seed);
 432 }
 433
 434 static void Handle_OP_PAUSE_PLAYING()
 435 {
 436   printf("OP_PAUSE_PLAYING: %d\n", buffer[0]);
 437   Error(ERR_NETWORK_CLIENT, "client %d pauses game", buffer[0]);
 438
 439   tape.pausing = TRUE;
 440   DrawVideoDisplay(VIDEO_STATE_PAUSE_ON,0);
 441 }
 442
 443 static void Handle_OP_CONTINUE_PLAYING()
 444 {
 445   printf("OP_CONTINUE_PLAYING: %d\n", buffer[0]);
 446   Error(ERR_NETWORK_CLIENT, "client %d continues game", buffer[0]);
 447
 448   tape.pausing = FALSE;
 449   DrawVideoDisplay(VIDEO_STATE_PAUSE_OFF,0);
 450 }
 451
 452 static void Handle_OP_STOP_PLAYING()
 453 {
 454   printf("OP_STOP_PLAYING: %d [%d]\n", buffer[0], buffer[2]);
 455   Error(ERR_NETWORK_CLIENT, "client %d stops game [%d]", buffer[0], buffer[2]);
 456
 457   if (game_status == GAME_MODE_PLAYING)
 458   {
 459     if (buffer[2] == NETWORK_STOP_BY_PLAYER)
 460       Request("Network game stopped by player!", REQ_CONFIRM);
 461     else if (buffer[2] == NETWORK_STOP_BY_ERROR)
 462       Request("Network game stopped due to internal error!", REQ_CONFIRM);
 463     else
 464       Request("Network game stopped!", REQ_CONFIRM);
 465   }
 466
 467   game_status = GAME_MODE_MAIN;
 468   DrawMainMenu();
 469 }
 470
 471 static void Handle_OP_MOVE_PLAYER(unsigned int len)
 472 {
 473   int server_frame_counter;
 474   int i;
 475
 476   if (!network_playing)
 477     return;
 478
 479   server_frame_counter =
 480     (buffer[2] << 24) | (buffer[3] << 16) | (buffer[4] << 8) | (buffer[5]);
 481
 482   if (server_frame_counter != FrameCounter)
 483   {
 484     Error(ERR_INFO, "client and servers frame counters out of sync");
 485     Error(ERR_INFO, "frame counter of client is %d", FrameCounter);
 486     Error(ERR_INFO, "frame counter of server is %d", server_frame_counter);
 487     Error(ERR_INFO, "this should not happen -- please debug");
 488
 489     stop_network_game = TRUE;
 490
 491     return;
 492   }
 493
 494   /* copy valid player actions */
 495   for (i = 0; i < MAX_PLAYERS; i++)
 496     stored_player[i].effective_action =
 497       (i < len - 6 && stored_player[i].active ? buffer[6 + i] : 0);
 498
 499   network_player_action_received = TRUE;
 500 }
 501
 502 static void HandleNetworkingMessages()
 503 {
 504   unsigned int message_length;
 505
 506   stop_network_game = FALSE;
 507
 508   while (nread >= 4 && nread >= 4 + readbuffer[3])
 509   {
 510     message_length = readbuffer[3];
 511     if (readbuffer[0] || readbuffer[1] || readbuffer[2])
 512       Error(ERR_EXIT, "wrong network server line length");
 513
 514     memcpy(buffer, &readbuffer[4], message_length);
 515     nread -= 4 + message_length;
 516     memmove(readbuffer, readbuffer + 4 + message_length, nread);
 517
 518     switch (buffer[1])
 519     {
 520       case OP_BAD_PROTOCOL_VERSION:
 521         Handle_OP_BAD_PROTOCOL_VERSION();
 522         break;
 523
 524       case OP_YOUR_NUMBER:
 525         Handle_OP_YOUR_NUMBER();
 526         break;
 527
 528       case OP_NUMBER_WANTED:
 529         Handle_OP_NUMBER_WANTED();
 530         break;
 531
 532       case OP_PLAYER_NAME:
 533         Handle_OP_PLAYER_NAME(message_length);
 534         break;
 535
 536       case OP_PLAYER_CONNECTED:
 537         Handle_OP_PLAYER_CONNECTED();
 538         break;
 539
 540       case OP_PLAYER_DISCONNECTED:
 541         Handle_OP_PLAYER_DISCONNECTED();
 542         break;
 543
 544       case OP_START_PLAYING:
 545         Handle_OP_START_PLAYING();
 546         break;
 547
 548       case OP_PAUSE_PLAYING:
 549         Handle_OP_PAUSE_PLAYING();
 550         break;
 551
 552       case OP_CONTINUE_PLAYING:
 553         Handle_OP_CONTINUE_PLAYING();
 554         break;
 555
 556       case OP_STOP_PLAYING:
 557         Handle_OP_STOP_PLAYING();
 558         break;
 559
 560       case OP_MOVE_PLAYER:
 561         Handle_OP_MOVE_PLAYER(message_length);
 562         break;
 563
 564       case OP_BROADCAST_MESSAGE:
 565         printf("OP_BROADCAST_MESSAGE: %d\n", buffer[0]);
 566         Error(ERR_NETWORK_CLIENT, "client %d sends message", buffer[0]);
 567         break;
 568     }
 569   }
 570
 571   fflush(stdout);
 572
 573   /* in case of internal error, stop network game */
 574   if (stop_network_game)
 575     SendToServer_StopPlaying(NETWORK_STOP_BY_ERROR);
 576 }
 577
 578 /* TODO */
 579
 580 void HandleNetworking()
 581 {
 582   int r = 0;
 583
 584   do
 585   {
 586     if ((r = SDLNet_CheckSockets(rfds, 1)) < 0)
 587       Error(ERR_EXIT, "HandleNetworking(): SDLNet_CheckSockets() failed");
 588
 589     if (r > 0)
 590     {
 591       r = SDLNet_TCP_Recv(sfd, readbuffer + nread, 1);
 592
 593       if (r < 0)
 594         Error(ERR_EXIT, "error reading from network server");
 595
 596       if (r == 0)
 597         Error(ERR_EXIT, "connection to network server lost");
 598
 599       nread += r;
 600
 601       HandleNetworkingMessages();
 602     }
 603   }
 604   while (r > 0);
 605 }
 606
 607 #endif /* NETWORK_AVALIABLE */