src/network.c

   1 /***********************************************************
   2 *  Rocks'n'Diamonds -- McDuffin Strikes Back!              *
   3 *----------------------------------------------------------*
   4 *  (c) 1995-98 Artsoft Entertainment                       *
   5 *              Holger Schemel                              *
   6 *              Oststrasse 11a                              *
   7 *              33604 Bielefeld                             *
   8 *              phone: ++49 +521 290471                     *
   9 *              email: aeglos@valinor.owl.de                *
  10 *----------------------------------------------------------*
  11 *  network.c                                               *
  12 ***********************************************************/
  13
  14 #ifndef MSDOS
  15
  16 #include <unistd.h>
  17 #include <signal.h>
  18 #include <sys/time.h>
  19 #include <sys/wait.h>
  20 #include <sys/socket.h>
  21 #include <netinet/in.h>
  22 #include <netinet/tcp.h>
  23 #include <arpa/inet.h>
  24 #include <netdb.h>
  25
  26 #include "network.h"
  27 #include "netserv.h"
  28 #include "game.h"
  29 #include "tape.h"
  30 #include "files.h"
  31 #include "tools.h"
  32 #include "buttons.h"
  33 #include "screens.h"
  34 #include "misc.h"
  35
  36 #define MAX_PLAYER_NAME_LEN 14
  37
  38 struct NetworkClientPlayerInfo
  39 {
  40   byte nr;
  41   char name[MAX_PLAYER_NAME_LEN + 2];
  42   struct NetworkClientPlayerInfo *next;
  43 };
  44
  45 static struct NetworkClientPlayerInfo first_player =
  46 {
  47   0,
  48   EMPTY_PLAYER_NAME,
  49   NULL
  50 };
  51
  52 /* server stuff */
  53
  54 static int sfd;
  55 static byte realbuffer[512];
  56 static byte readbuffer[MAX_BUFFER_SIZE], writbuffer[MAX_BUFFER_SIZE];
  57 static byte *buffer = realbuffer + 4;
  58 static int nread = 0, nwrite = 0;
  59
  60 static void SendBufferToServer(int size)
  61 {
  62   if (!options.network)
  63     return;
  64
  65   realbuffer[0] = realbuffer[1] = realbuffer[2] = 0;
  66   realbuffer[3] = (byte)size;
  67   buffer[0] = 0;
  68
  69   if (nwrite + 4 + size >= MAX_BUFFER_SIZE)
  70     Error(ERR_EXIT, "internal error: network send buffer overflow");
  71
  72   memcpy(writbuffer + nwrite, realbuffer, 4 + size);
  73   nwrite += 4 + size;
  74
  75   /* directly send the buffer to the network server */
  76   write(sfd, writbuffer, nwrite);
  77   nwrite = 0;
  78 }
  79
  80 struct NetworkClientPlayerInfo *getNetworkPlayer(int player_nr)
  81 {
  82   struct NetworkClientPlayerInfo *player = NULL;
  83
  84   for (player = &first_player; player; player = player->next)
  85     if (player->nr == player_nr)
  86       break;
  87
  88   if (player == NULL)   /* should not happen */
  89     Error(ERR_EXIT, "protocol error: reference to non-existing player %d",
  90           player_nr);
  91
  92   return player;
  93 }
  94
  95 char *getNetworkPlayerName(int player_nr)
  96 {
  97   struct NetworkClientPlayerInfo *player;
  98
  99   if (player_nr == 0)
 100     return("the network game server");
 101   else if (player_nr == first_player.nr)
 102     return("you");
 103   else
 104     for (player=&first_player; player; player=player->next)
 105       if (player->nr == player_nr && player->name && strlen(player->name))
 106         return(player->name);
 107
 108   return(EMPTY_PLAYER_NAME);
 109 }
 110
 111 static void StartNetworkServer(int port)
 112 {
 113   switch (fork())
 114   {
 115     case 0:
 116       NetworkServer(port, options.serveronly);
 117
 118       /* never reached */
 119       exit(0);
 120
 121     case -1:
 122       Error(ERR_WARN,
 123             "cannot create network server process - no network playing");
 124       options.network = FALSE;
 125       return;
 126
 127     default:
 128       /* we are parent process -- resume normal operation */
 129       return;
 130   }
 131 }
 132
 133 boolean ConnectToServer(char *hostname, int port)
 134 {
 135   struct sockaddr_in s;
 136   struct protoent *tcpproto;
 137   int on = 1, i;
 138
 139   if (hostname)
 140   {
 141     if ((s.sin_addr.s_addr = inet_addr(hostname)) == -1)
 142     {
 143       struct hostent *host;
 144
 145       if ((host = gethostbyname(hostname)) == NULL)
 146         Error(ERR_EXIT, "cannot locate host '%s'", hostname);
 147
 148       s.sin_addr = *(struct in_addr *)(host->h_addr_list[0]);
 149     }
 150   }
 151   else
 152     s.sin_addr.s_addr = inet_addr("127.0.0.1");         /* localhost */
 153
 154   if (port == 0)
 155     port = DEFAULT_SERVER_PORT;
 156
 157   s.sin_port = htons(port);
 158   s.sin_family = AF_INET;
 159
 160   sfd = socket(PF_INET, SOCK_STREAM, 0);
 161   if (sfd < 0)
 162     Error(ERR_EXIT, "out of file descriptors");
 163
 164   if ((tcpproto = getprotobyname("tcp")) != NULL)
 165     setsockopt(sfd, tcpproto->p_proto, TCP_NODELAY, (char *)&on, sizeof(int));
 166
 167   if (connect(sfd, (struct sockaddr *)&s, sizeof(s)) == 0)      /* connected */
 168     return TRUE;
 169
 170   if (hostname) /* connect to specified server failed */
 171     return FALSE;
 172
 173   printf("No rocksndiamonds server on localhost - starting up one ...\n");
 174   StartNetworkServer(port);
 175
 176   /* wait for server to start up and try connecting several times */
 177   for (i=0; i<6; i++)
 178   {
 179     Delay(500);         /* wait 500 ms == 0.5 seconds */
 180     close(sfd);
 181
 182     sfd = socket(PF_INET, SOCK_STREAM, 0);
 183     if (sfd < 0)
 184       Error(ERR_EXIT, "out of file descriptors");
 185
 186     setsockopt(sfd, tcpproto->p_proto, TCP_NODELAY, (char *)&on, sizeof(int));
 187
 188     if (connect(sfd, (struct sockaddr *)&s, sizeof(s)) >= 0)    /* connected */
 189       return TRUE;
 190   }
 191
 192   /* when reaching this point, connect to newly started server has failed */
 193   return FALSE;
 194 }
 195
 196 void SendToServer_PlayerName(char *player_name)
 197 {
 198   int len_player_name = strlen(player_name);
 199
 200   buffer[1] = OP_PLAYER_NAME;
 201   memcpy(&buffer[2], player_name, len_player_name);
 202   SendBufferToServer(2 + len_player_name);
 203   Error(ERR_NETWORK_CLIENT, "you set your player name to \"%s\"", player_name);
 204 }
 205
 206 void SendToServer_ProtocolVersion()
 207 {
 208   buffer[1] = OP_PROTOCOL_VERSION;
 209   buffer[2] = PROTOCOL_VERSION_1;
 210   buffer[3] = PROTOCOL_VERSION_2;
 211   buffer[4] = PROTOCOL_VERSION_3;
 212
 213   SendBufferToServer(5);
 214 }
 215
 216 void SendToServer_NrWanted(int nr_wanted)
 217 {
 218   buffer[1] = OP_NUMBER_WANTED;
 219   buffer[2] = nr_wanted;
 220
 221   SendBufferToServer(3);
 222 }
 223
 224 void SendToServer_StartPlaying()
 225 {
 226   unsigned long new_random_seed = InitRND(NEW_RANDOMIZE);
 227
 228   buffer[1] = OP_START_PLAYING;
 229   buffer[2] = (byte)(level_nr >> 8);
 230   buffer[3] = (byte)(level_nr & 0xff);
 231   buffer[4] = (byte)(leveldir_nr >> 8);
 232   buffer[5] = (byte)(leveldir_nr & 0xff);
 233
 234   buffer[6] = (unsigned char)((new_random_seed >> 24) & 0xff);
 235   buffer[7] = (unsigned char)((new_random_seed >> 16) & 0xff);
 236   buffer[8] = (unsigned char)((new_random_seed >>  8) & 0xff);
 237   buffer[9] = (unsigned char)((new_random_seed >>  0) & 0xff);
 238
 239   strcpy((char *)&buffer[10], leveldir[leveldir_nr].name);
 240
 241   SendBufferToServer(10 + strlen(leveldir[leveldir_nr].name)+1);
 242 }
 243
 244 void SendToServer_PausePlaying()
 245 {
 246   buffer[1] = OP_PAUSE_PLAYING;
 247
 248   SendBufferToServer(2);
 249 }
 250
 251 void SendToServer_ContinuePlaying()
 252 {
 253   buffer[1] = OP_CONTINUE_PLAYING;
 254
 255   SendBufferToServer(2);
 256 }
 257
 258 void SendToServer_StopPlaying()
 259 {
 260   buffer[1] = OP_STOP_PLAYING;
 261
 262   SendBufferToServer(2);
 263 }
 264
 265 void SendToServer_MovePlayer(byte player_action)
 266 {
 267   buffer[1] = OP_MOVE_FIGURE;
 268   buffer[2] = player_action;
 269
 270   SendBufferToServer(3);
 271 }
 272
 273 static void Handle_OP_BAD_PROTOCOL_VERSION()
 274 {
 275   Error(ERR_WARN, "protocol version mismatch");
 276   Error(ERR_EXIT, "server expects %d.%d.x instead of %d.%d.%d",
 277         buffer[2], buffer[3],
 278         PROTOCOL_VERSION_1, PROTOCOL_VERSION_2, PROTOCOL_VERSION_3);
 279 }
 280
 281 static void Handle_OP_YOUR_NUMBER()
 282 {
 283   int new_client_nr = buffer[2];
 284   int new_index_nr = new_client_nr - 1;
 285   struct PlayerInfo *old_local_player = local_player;
 286   struct PlayerInfo *new_local_player = &stored_player[new_index_nr];
 287
 288   printf("OP_YOUR_NUMBER: %d\n", buffer[0]);
 289   first_player.nr = new_client_nr;
 290
 291   if (old_local_player != new_local_player)
 292   {
 293     /* copy existing player settings and change to new player */
 294
 295     *new_local_player = *old_local_player;
 296     old_local_player->connected = FALSE;
 297     local_player = new_local_player;
 298   }
 299
 300   if (first_player.nr > MAX_PLAYERS)
 301     Error(ERR_EXIT, "sorry - no more than %d players", MAX_PLAYERS);
 302
 303   Error(ERR_NETWORK_CLIENT, "you get client # %d", new_client_nr);
 304 }
 305
 306 static void Handle_OP_NUMBER_WANTED()
 307 {
 308   int client_nr_wanted = buffer[2];
 309   int old_client_nr = buffer[0];
 310   int new_client_nr = buffer[3];
 311   int old_index_nr = old_client_nr - 1;
 312   int new_index_nr = new_client_nr - 1;
 313   int index_nr_wanted = client_nr_wanted - 1;
 314   struct PlayerInfo *old_player = &stored_player[old_index_nr];
 315   struct PlayerInfo *new_player = &stored_player[new_index_nr];
 316
 317   printf("OP_NUMBER_WANTED: %d\n", buffer[0]);
 318
 319   if (new_client_nr == client_nr_wanted)        /* switching succeeded */
 320   {
 321     struct NetworkClientPlayerInfo *player;
 322
 323     if (old_client_nr != client_nr_wanted)      /* client's nr has changed */
 324       Error(ERR_NETWORK_CLIENT, "client %d switches to # %d",
 325             old_client_nr, new_client_nr);
 326     else if (old_client_nr == first_player.nr)  /* local player keeps his nr */
 327       Error(ERR_NETWORK_CLIENT, "keeping client # %d", new_client_nr);
 328
 329     if (old_client_nr != new_client_nr)
 330     {
 331       /* copy existing player settings and change to new player */
 332
 333       *new_player = *old_player;
 334       old_player->connected = FALSE;
 335     }
 336
 337     player = getNetworkPlayer(old_client_nr);
 338     player->nr = new_client_nr;
 339
 340     if (old_player == local_player)             /* local player switched */
 341       local_player = new_player;
 342   }
 343   else if (old_client_nr == first_player.nr)    /* failed -- local player? */
 344   {
 345     char *color[] = { "yellow", "red", "green", "blue" };
 346     char request[100];
 347
 348     sprintf(request, "Sorry ! %s player still exists ! You are %s player !",
 349             color[index_nr_wanted], color[new_index_nr]);
 350     Request(request, REQ_CONFIRM);
 351
 352     Error(ERR_NETWORK_CLIENT, "cannot switch -- you keep client # %d",
 353           new_client_nr);
 354   }
 355 }
 356
 357 static void Handle_OP_PLAYER_NAME(unsigned int len)
 358 {
 359   struct NetworkClientPlayerInfo *player;
 360   int player_nr = (int)buffer[0];
 361
 362   printf("OP_PLAYER_NAME: %d\n", player_nr);
 363   player = getNetworkPlayer(player_nr);
 364   buffer[len] = 0;
 365   Error(ERR_NETWORK_CLIENT, "client %d calls itself \"%s\"",
 366         buffer[0], &buffer[2]);
 367   strncpy(player->name, (char *)&buffer[2], MAX_PLAYER_NAME_LEN);
 368 }
 369
 370 static void Handle_OP_PLAYER_CONNECTED()
 371 {
 372   struct NetworkClientPlayerInfo *player, *last_player = NULL;
 373   int new_client_nr = (int)buffer[0];
 374   int new_index_nr = new_client_nr - 1;
 375
 376   printf("OP_PLAYER_CONNECTED: %d\n", new_client_nr);
 377   Error(ERR_NETWORK_CLIENT, "new client %d connected", new_client_nr);
 378
 379   for (player=&first_player; player; player=player->next)
 380   {
 381     if (player->nr == new_client_nr)
 382       Error(ERR_EXIT, "multiplayer server sent duplicate player id");
 383
 384     last_player = player;
 385   }
 386
 387   last_player->next = player =
 388     checked_malloc(sizeof(struct NetworkClientPlayerInfo));
 389   player->nr = new_client_nr;
 390   player->name[0] = '\0';
 391   player->next = NULL;
 392
 393   stored_player[new_index_nr].connected = TRUE;
 394 }
 395
 396 static void Handle_OP_PLAYER_DISCONNECTED()
 397 {
 398   struct NetworkClientPlayerInfo *player, *player_disconnected;
 399   int player_nr = (int)buffer[0];
 400
 401   printf("OP_PLAYER_DISCONNECTED: %d\n", player_nr);
 402   player_disconnected = getNetworkPlayer(player_nr);
 403   Error(ERR_NETWORK_CLIENT, "client %d (%s) disconnected",
 404         player_nr, getNetworkPlayerName(buffer[0]));
 405
 406   for (player=&first_player; player; player=player->next)
 407     if (player->next == player_disconnected)
 408       player->next = player_disconnected->next;
 409   free(player_disconnected);
 410 }
 411
 412 static void Handle_OP_START_PLAYING()
 413 {
 414   int new_level_nr, new_leveldir_nr;
 415   unsigned long new_random_seed;
 416   char *new_leveldir_name;
 417
 418   new_level_nr = (buffer[2] << 8) + buffer[3];
 419   new_leveldir_nr = (buffer[4] << 8) + buffer[5];
 420   new_random_seed =
 421     (buffer[6] << 24) | (buffer[7] << 16) | (buffer[8] << 8) | (buffer[9]);
 422   new_leveldir_name = (char *)&buffer[10];
 423
 424   printf("OP_START_PLAYING: %d\n", buffer[0]);
 425   Error(ERR_NETWORK_CLIENT,
 426         "client %d starts game [level %d from levedir %d (%s)]\n",
 427         buffer[0], new_level_nr, new_leveldir_nr, new_leveldir_name);
 428
 429   if (strcmp(leveldir[new_leveldir_nr].name, new_leveldir_name) != 0)
 430     Error(ERR_WARN, "no such level directory: '%s'",new_leveldir_name);
 431
 432   leveldir_nr = new_leveldir_nr;
 433   level_nr = new_level_nr;
 434
 435   TapeErase();
 436   LoadTape(level_nr);
 437   LoadLevel(level_nr);
 438
 439   if (setup.autorecord)
 440     TapeStartRecording();
 441
 442   if (tape.recording)
 443     tape.random_seed = new_random_seed;
 444
 445   InitRND(new_random_seed);
 446
 447   game_status = PLAYING;
 448   InitGame();
 449 }
 450
 451 static void Handle_OP_PAUSE_PLAYING()
 452 {
 453   printf("OP_PAUSE_PLAYING: %d\n", buffer[0]);
 454   Error(ERR_NETWORK_CLIENT, "client %d pauses game", buffer[0]);
 455
 456   tape.pausing = TRUE;
 457   DrawVideoDisplay(VIDEO_STATE_PAUSE_ON,0);
 458 }
 459
 460 static void Handle_OP_CONTINUE_PLAYING()
 461 {
 462   printf("OP_CONTINUE_PLAYING: %d\n", buffer[0]);
 463   Error(ERR_NETWORK_CLIENT, "client %d continues game", buffer[0]);
 464
 465   tape.pausing = FALSE;
 466   DrawVideoDisplay(VIDEO_STATE_PAUSE_OFF,0);
 467 }
 468
 469 static void Handle_OP_STOP_PLAYING()
 470 {
 471   printf("OP_STOP_PLAYING: %d\n", buffer[0]);
 472   Error(ERR_NETWORK_CLIENT, "client %d stops game", buffer[0]);
 473
 474   game_status = MAINMENU;
 475   DrawMainMenu();
 476 }
 477
 478 static void Handle_OP_MOVE_FIGURE(unsigned int len)
 479 {
 480   int server_frame_counter;
 481   int i;
 482
 483   if (!network_playing)
 484     return;
 485
 486   server_frame_counter =
 487     (buffer[2] << 24) | (buffer[3] << 16) | (buffer[4] << 8) | (buffer[5]);
 488
 489   if (server_frame_counter != FrameCounter)
 490   {
 491     Error(ERR_RETURN, "client and servers frame counters out of sync");
 492     Error(ERR_RETURN, "frame counter of client is %d", FrameCounter);
 493     Error(ERR_RETURN, "frame counter of server is %d", server_frame_counter);
 494     Error(ERR_EXIT,   "this should not happen -- please debug");
 495   }
 496
 497   /* copy valid player actions */
 498   for (i=0; i<MAX_PLAYERS; i++)
 499     stored_player[i].effective_action =
 500       (i < len - 6 && stored_player[i].active ? buffer[6 + i] : 0);
 501
 502   network_player_action_received = TRUE;
 503 }
 504
 505 static void HandleNetworkingMessages()
 506 {
 507   unsigned int message_length;
 508
 509   while (nread >= 4 && nread >= 4 + readbuffer[3])
 510   {
 511     message_length = readbuffer[3];
 512     if (readbuffer[0] || readbuffer[1] || readbuffer[2])
 513       Error(ERR_EXIT, "wrong network server line length");
 514
 515     memcpy(buffer, &readbuffer[4], message_length);
 516     nread -= 4 + message_length;
 517     memmove(readbuffer, readbuffer + 4 + message_length, nread);
 518
 519     switch(buffer[1])
 520     {
 521       case OP_BAD_PROTOCOL_VERSION:
 522         Handle_OP_BAD_PROTOCOL_VERSION();
 523         break;
 524
 525       case OP_YOUR_NUMBER:
 526         Handle_OP_YOUR_NUMBER();
 527         break;
 528
 529       case OP_NUMBER_WANTED:
 530         Handle_OP_NUMBER_WANTED();
 531         break;
 532
 533       case OP_PLAYER_NAME:
 534         Handle_OP_PLAYER_NAME(message_length);
 535         break;
 536
 537       case OP_PLAYER_CONNECTED:
 538         Handle_OP_PLAYER_CONNECTED();
 539         break;
 540
 541       case OP_PLAYER_DISCONNECTED:
 542         Handle_OP_PLAYER_DISCONNECTED();
 543         break;
 544
 545       case OP_START_PLAYING:
 546         Handle_OP_START_PLAYING();
 547         break;
 548
 549       case OP_PAUSE_PLAYING:
 550         Handle_OP_PAUSE_PLAYING();
 551         break;
 552
 553       case OP_CONTINUE_PLAYING:
 554         Handle_OP_CONTINUE_PLAYING();
 555         break;
 556
 557       case OP_STOP_PLAYING:
 558         Handle_OP_STOP_PLAYING();
 559         break;
 560
 561       case OP_MOVE_FIGURE:
 562         Handle_OP_MOVE_FIGURE(message_length);
 563         break;
 564
 565       case OP_BROADCAST_MESSAGE:
 566         printf("OP_BROADCAST_MESSAGE: %d\n", buffer[0]);
 567         Error(ERR_NETWORK_CLIENT, "client %d sends message", buffer[0]);
 568         break;
 569     }
 570   }
 571
 572   fflush(stdout);
 573 }
 574
 575 void HandleNetworking()
 576 {
 577   static struct timeval tv = { 0, 0 };
 578   fd_set rfds;
 579   int r = 0;
 580
 581   FD_ZERO(&rfds);
 582   FD_SET(sfd, &rfds);
 583
 584   r = select(sfd + 1, &rfds, NULL, NULL, &tv);
 585
 586   if (r < 0 && errno != EINTR)
 587     Error(ERR_EXIT, "HandleNetworking(): select() failed");
 588
 589   if (r < 0)
 590     FD_ZERO(&rfds);
 591
 592   if (FD_ISSET(sfd, &rfds))
 593   {
 594     int r;
 595
 596     r = read(sfd, readbuffer + nread, MAX_BUFFER_SIZE - nread);
 597
 598     if (r < 0)
 599       Error(ERR_EXIT, "error reading from network server");
 600
 601     if (r == 0)
 602       Error(ERR_EXIT, "connection to network server lost");
 603
 604     nread += r;
 605
 606     HandleNetworkingMessages();
 607   }
 608 }
 609
 610 #endif /* !MSDOS */