# network.cpp

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    00001 /* $Id: network.cpp 19624 2010-04-13 21:40:24Z rubidium $ */
    00002
    00003 /*
    00004  * This file is part of OpenTTD.
    00005  * OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2.
    00006  * OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
    00007  * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
    00008  */
    00009
    00012 #include "../stdafx.h"
    00013
    00014 #ifdef ENABLE_NETWORK
    00015
    00016 #include "../strings_func.h"
    00017 #include "../command_func.h"
    00018 #include "../date_func.h"
    00019 #include "network_client.h"
    00020 #include "network_server.h"
    00021 #include "network_content.h"
    00022 #include "network_udp.h"
    00023 #include "network_gamelist.h"
    00024 #include "network_base.h"
    00025 #include "core/udp.h"
    00026 #include "core/host.h"
    00027 #include "network_gui.h"
    00028 #include "../console_func.h"
    00029 #include "../3rdparty/md5/md5.h"
    00030 #include "../core/random_func.hpp"
    00031 #include "../window_func.h"
    00032 #include "../company_func.h"
    00033 #include "../company_base.h"
    00034 #include "../landscape_type.h"
    00035 #include "../rev.h"
    00036 #include "../core/pool_func.hpp"
    00037 #include "../gfx_func.h"
    00038 #include "table/strings.h"
    00039
    00040 #ifdef DEBUG_DUMP_COMMANDS
    00041 #include "../fileio_func.h"
    00043 bool _ddc_fastforward = true;
    00044 #endif /* DEBUG_DUMP_COMMANDS */
    00045
    00046 DECLARE_POSTFIX_INCREMENT(ClientID);
    00047
    00048 assert_compile(NetworkClientInfoPool::MAX_SIZE == NetworkClientSocketPool::MAX_SIZE);
    00049
    00050 NetworkClientInfoPool _networkclientinfo_pool("NetworkClientInfo");
    00051 INSTANTIATE_POOL_METHODS(NetworkClientInfo)
    00052
    00053 bool _networking;
    00054 bool _network_server;
    00055 bool _network_available;
    00056 bool _network_dedicated;
    00057 bool _is_network_server;
    00058 NetworkServerGameInfo _network_game_info;
    00059 NetworkCompanyState *_network_company_states = NULL;
    00060 ClientID _network_own_client_id;
    00061 ClientID _redirect_console_to_client;
    00062 bool _network_need_advertise;
    00063 uint32 _network_last_advertise_frame;
    00064 uint8 _network_reconnect;
    00065 StringList _network_bind_list;
    00066 StringList _network_host_list;
    00067 StringList _network_ban_list;
    00068 uint32 _frame_counter_server; // The frame_counter of the server, if in network-mode
    00069 uint32 _frame_counter_max; // To where we may go with our clients
    00070 uint32 _frame_counter;
    00071 uint32 _last_sync_frame; // Used in the server to store the last time a sync packet was sent to clients.
    00072 NetworkAddressList _broadcast_list;
    00073 uint32 _sync_seed_1;
    00074 #ifdef NETWORK_SEND_DOUBLE_SEED
    00075 uint32 _sync_seed_2;
    00076 #endif
    00077 uint32 _sync_frame;
    00078 bool _network_first_time;
    00079 bool _network_udp_server;
    00080 uint16 _network_udp_broadcast;
    00081 uint8 _network_advertise_retries;
    00082 CompanyMask _network_company_passworded;
    00083
    00084 /* Check whether NETWORK_NUM_LANDSCAPES is still in sync with NUM_LANDSCAPE */
    00085 assert_compile((int)NETWORK_NUM_LANDSCAPES == (int)NUM_LANDSCAPE);
    00086 assert_compile((int)NETWORK_COMPANY_NAME_LENGTH == MAX_LENGTH_COMPANY_NAME_BYTES);
    00087
    00088 extern NetworkUDPSocketHandler *_udp_client_socket;
    00089 extern NetworkUDPSocketHandler *_udp_server_socket;
    00090 extern NetworkUDPSocketHandler *_udp_master_socket;
    00091
    00092 /* The listen socket for the server */
    00093 static SocketList _listensockets;
    00094
    00095 /* The amount of clients connected */
    00096 static byte _network_clients_connected = 0;
    00097 /* The identifier counter for new clients (is never decreased) */
    00098 static ClientID _network_client_id = CLIENT_ID_FIRST;
    00099
    00100 /* Some externs / forwards */
    00101 extern void StateGameLoop();
    00102
    00106 NetworkClientInfo::~NetworkClientInfo()
    00107 {
    00108   /* Delete the chat window, if you were chatting with this client. */
    00109   InvalidateWindowData(WC_SEND_NETWORK_MSG, DESTTYPE_CLIENT, this->client_id);
    00110 }
    00111
    00117 NetworkClientInfo *NetworkFindClientInfoFromIndex(ClientIndex index)
    00118 {
    00119   return NetworkClientInfo::GetIfValid(index);
    00120 }
    00121
    00127 NetworkClientInfo *NetworkFindClientInfoFromClientID(ClientID client_id)
    00128 {
    00129   NetworkClientInfo *ci;
    00130
    00131   FOR_ALL_CLIENT_INFOS(ci) {
    00132     if (ci->client_id == client_id) return ci;
    00133   }
    00134
    00135   return NULL;
    00136 }
    00137
    00143 NetworkClientInfo *NetworkFindClientInfoFromIP(const char *ip)
    00144 {
    00145   NetworkClientInfo *ci;
    00146   NetworkAddress address(ip);
    00147
    00148   if (address.GetAddressLength() == 0) return NULL;
    00149
    00150   FOR_ALL_CLIENT_INFOS(ci) {
    00151     if (ci->client_address == address) return ci;
    00152   }
    00153
    00154   return NULL;
    00155 }
    00156
    00162 NetworkClientSocket *NetworkFindClientStateFromClientID(ClientID client_id)
    00163 {
    00164   NetworkClientSocket *cs;
    00165
    00166   FOR_ALL_CLIENT_SOCKETS(cs) {
    00167     if (cs->client_id == client_id) return cs;
    00168   }
    00169
    00170   return NULL;
    00171 }
    00172
    00173 /* NetworkGetClientName is a server-safe function to get the name of the client
    00174  *  if the user did not send it yet, Client #<no> is used. */
    00175 void NetworkGetClientName(char *client_name, size_t size, const NetworkClientSocket *cs)
    00176 {
    00177   const NetworkClientInfo *ci = cs->GetInfo();
    00178
    00179   if (StrEmpty(ci->client_name)) {
    00180     snprintf(client_name, size, "Client #%4d", cs->client_id);
    00181   } else {
    00182     ttd_strlcpy(client_name, ci->client_name, size);
    00183   }
    00184 }
    00185
    00186 byte NetworkSpectatorCount()
    00187 {
    00188   const NetworkClientInfo *ci;
    00189   byte count = 0;
    00190
    00191   FOR_ALL_CLIENT_INFOS(ci) {
    00192     if (ci->client_playas == COMPANY_SPECTATOR) count++;
    00193   }
    00194
    00195   /* Don't count a dedicated server as spectator */
    00196   if (_network_dedicated) count--;
    00197
    00198   return count;
    00199 }
    00200
    00206 bool NetworkCompanyIsPassworded(CompanyID company_id)
    00207 {
    00208   return HasBit(_network_company_passworded, company_id);
    00209 }
    00210
    00211 /* This puts a text-message to the console, or in the future, the chat-box,
    00212  *  (to keep it all a bit more general)
    00213  * If 'self_send' is true, this is the client who is sending the message */
    00214 void NetworkTextMessage(NetworkAction action, ConsoleColour colour, bool self_send, const char *name, const char *str, int64 data)
    00215 {
    00216   const int duration = 10; // Game days the messages stay visible
    00217
    00218   StringID strid;
    00219   switch (action) {
    00220     case NETWORK_ACTION_SERVER_MESSAGE:
    00221       /* Ignore invalid messages */
    00222       strid = STR_NETWORK_SERVER_MESSAGE;
    00223       colour = CC_DEFAULT;
    00224       break;
    00225     case NETWORK_ACTION_COMPANY_SPECTATOR:
    00226       colour = CC_DEFAULT;
    00227       strid = STR_NETWORK_MESSAGE_CLIENT_COMPANY_SPECTATE;
    00228       break;
    00229     case NETWORK_ACTION_COMPANY_JOIN:
    00230       colour = CC_DEFAULT;
    00231       strid = STR_NETWORK_MESSAGE_CLIENT_COMPANY_JOIN;
    00232       break;
    00233     case NETWORK_ACTION_COMPANY_NEW:
    00234       colour = CC_DEFAULT;
    00235       strid = STR_NETWORK_MESSAGE_CLIENT_COMPANY_NEW;
    00236       break;
    00237     case NETWORK_ACTION_JOIN:
    00238       /* Show the Client ID for the server but not for the client. */
    00239       strid = _network_server ? STR_NETWORK_MESSAGE_CLIENT_JOINED_ID :  STR_NETWORK_MESSAGE_CLIENT_JOINED;
    00240       break;
    00241     case NETWORK_ACTION_LEAVE:          strid = STR_NETWORK_MESSAGE_CLIENT_LEFT; break;
    00242     case NETWORK_ACTION_NAME_CHANGE:    strid = STR_NETWORK_MESSAGE_NAME_CHANGE; break;
    00243     case NETWORK_ACTION_GIVE_MONEY:     strid = self_send ? STR_NETWORK_MESSAGE_GAVE_MONEY_AWAY : STR_NETWORK_MESSAGE_GIVE_MONEY;   break;
    00244     case NETWORK_ACTION_CHAT_COMPANY:   strid = self_send ? STR_NETWORK_CHAT_TO_COMPANY : STR_NETWORK_CHAT_COMPANY; break;
    00245     case NETWORK_ACTION_CHAT_CLIENT:    strid = self_send ? STR_NETWORK_CHAT_TO_CLIENT  : STR_NETWORK_CHAT_CLIENT;  break;
    00246     default:                            strid = STR_NETWORK_CHAT_ALL; break;
    00247   }
    00248
    00249   char message[1024];
    00250   SetDParamStr(0, name);
    00251   SetDParamStr(1, str);
    00252   SetDParam(2, data);
    00253   GetString(message, strid, lastof(message));
    00254
    00255   DEBUG(desync, 1, "msg: %08x; %02x; %s", _date, _date_fract, message);
    00256   IConsolePrintF(colour, "%s", message);
    00257   NetworkAddChatMessage((TextColour)colour, duration, "%s", message);
    00258 }
    00259
    00260 /* Calculate the frame-lag of a client */
    00261 uint NetworkCalculateLag(const NetworkClientSocket *cs)
    00262 {
    00263   int lag = cs->last_frame_server - cs->last_frame;
    00264   /* This client has missed his ACK packet after 1 DAY_TICKS..
    00265    *  so we increase his lag for every frame that passes!
    00266    * The packet can be out by a max of _net_frame_freq */
    00267   if (cs->last_frame_server + DAY_TICKS + _settings_client.network.frame_freq < _frame_counter)
    00268     lag += _frame_counter - (cs->last_frame_server + DAY_TICKS + _settings_client.network.frame_freq);
    00269
    00270   return lag;
    00271 }
    00272
    00273
    00274 /* There was a non-recoverable error, drop back to the main menu with a nice
    00275  *  error */
    00276 static void NetworkError(StringID error_string)
    00277 {
    00278   _switch_mode = SM_MENU;
    00279   extern StringID _switch_mode_errorstr;
    00280   _switch_mode_errorstr = error_string;
    00281 }
    00282
    00283 static void ServerStartError(const char *error)
    00284 {
    00285   DEBUG(net, 0, "[server] could not start network: %s",error);
    00286   NetworkError(STR_NETWORK_ERROR_SERVER_START);
    00287 }
    00288
    00289 static void NetworkClientError(NetworkRecvStatus res, NetworkClientSocket *cs)
    00290 {
    00291   /* First, send a CLIENT_ERROR to the server, so he knows we are
    00292    *  disconnection (and why!) */
    00293   NetworkErrorCode errorno;
    00294
    00295   /* We just want to close the connection.. */
    00296   if (res == NETWORK_RECV_STATUS_CLOSE_QUERY) {
    00297     cs->NetworkSocketHandler::CloseConnection();
    00298     NetworkCloseClient(cs, res);
    00299     _networking = false;
    00300
    00301     DeleteWindowById(WC_NETWORK_STATUS_WINDOW, 0);
    00302     return;
    00303   }
    00304
    00305   switch (res) {
    00306     case NETWORK_RECV_STATUS_DESYNC:          errorno = NETWORK_ERROR_DESYNC; break;
    00307     case NETWORK_RECV_STATUS_SAVEGAME:        errorno = NETWORK_ERROR_SAVEGAME_FAILED; break;
    00308     case NETWORK_RECV_STATUS_NEWGRF_MISMATCH: errorno = NETWORK_ERROR_NEWGRF_MISMATCH; break;
    00309     default:                                  errorno = NETWORK_ERROR_GENERAL; break;
    00310   }
    00311
    00312   /* This means we fucked up and the server closed the connection */
    00313   if (res != NETWORK_RECV_STATUS_SERVER_ERROR && res != NETWORK_RECV_STATUS_SERVER_FULL &&
    00314       res != NETWORK_RECV_STATUS_SERVER_BANNED) {
    00315     SEND_COMMAND(PACKET_CLIENT_ERROR)(errorno);
    00316   }
    00317
    00318   _switch_mode = SM_MENU;
    00319   NetworkCloseClient(cs, res);
    00320   _networking = false;
    00321 }
    00322
    00328 StringID GetNetworkErrorMsg(NetworkErrorCode err)
    00329 {
    00330   /* List of possible network errors, used by
    00331    * PACKET_SERVER_ERROR and PACKET_CLIENT_ERROR */
    00332   static const StringID network_error_strings[] = {
    00333     STR_NETWORK_ERROR_CLIENT_GENERAL,
    00334     STR_NETWORK_ERROR_CLIENT_DESYNC,
    00335     STR_NETWORK_ERROR_CLIENT_SAVEGAME,
    00336     STR_NETWORK_ERROR_CLIENT_CONNECTION_LOST,
    00337     STR_NETWORK_ERROR_CLIENT_PROTOCOL_ERROR,
    00338     STR_NETWORK_ERROR_CLIENT_NEWGRF_MISMATCH,
    00339     STR_NETWORK_ERROR_CLIENT_NOT_AUTHORIZED,
    00340     STR_NETWORK_ERROR_CLIENT_NOT_EXPECTED,
    00341     STR_NETWORK_ERROR_CLIENT_WRONG_REVISION,
    00342     STR_NETWORK_ERROR_CLIENT_NAME_IN_USE,
    00343     STR_NETWORK_ERROR_CLIENT_WRONG_PASSWORD,
    00344     STR_NETWORK_ERROR_CLIENT_COMPANY_MISMATCH,
    00345     STR_NETWORK_ERROR_CLIENT_KICKED,
    00346     STR_NETWORK_ERROR_CLIENT_CHEATER,
    00347     STR_NETWORK_ERROR_CLIENT_SERVER_FULL
    00348   };
    00349
    00350   if (err >= (ptrdiff_t)lengthof(network_error_strings)) err = NETWORK_ERROR_GENERAL;
    00351
    00352   return network_error_strings[err];
    00353 }
    00354
    00360 void NetworkHandlePauseChange(PauseMode prev_mode, PauseMode changed_mode)
    00361 {
    00362   if (!_networking) return;
    00363
    00364   switch (changed_mode) {
    00365     case PM_PAUSED_NORMAL:
    00366     case PM_PAUSED_JOIN:
    00367     case PM_PAUSED_ACTIVE_CLIENTS: {
    00368       bool changed = ((_pause_mode == PM_UNPAUSED) != (prev_mode == PM_UNPAUSED));
    00369       bool paused = (_pause_mode != PM_UNPAUSED);
    00370       if (!paused && !changed) return;
    00371
    00372       StringID str;
    00373       if (!changed) {
    00374         int i = -1;
    00375         if ((_pause_mode & PM_PAUSED_NORMAL) != PM_UNPAUSED)         SetDParam(++i, STR_NETWORK_SERVER_MESSAGE_GAME_REASON_MANUAL);
    00376         if ((_pause_mode & PM_PAUSED_JOIN) != PM_UNPAUSED)           SetDParam(++i, STR_NETWORK_SERVER_MESSAGE_GAME_REASON_CONNECTING_CLIENTS);
    00377         if ((_pause_mode & PM_PAUSED_ACTIVE_CLIENTS) != PM_UNPAUSED) SetDParam(++i, STR_NETWORK_SERVER_MESSAGE_GAME_REASON_NOT_ENOUGH_PLAYERS);
    00378         str = STR_NETWORK_SERVER_MESSAGE_GAME_STILL_PAUSED_1 + i;
    00379       } else {
    00380         switch (changed_mode) {
    00381           case PM_PAUSED_NORMAL:         SetDParam(0, STR_NETWORK_SERVER_MESSAGE_GAME_REASON_MANUAL); break;
    00382           case PM_PAUSED_JOIN:           SetDParam(0, STR_NETWORK_SERVER_MESSAGE_GAME_REASON_CONNECTING_CLIENTS); break;
    00383           case PM_PAUSED_ACTIVE_CLIENTS: SetDParam(0, STR_NETWORK_SERVER_MESSAGE_GAME_REASON_NOT_ENOUGH_PLAYERS); break;
    00384           default: NOT_REACHED();
    00385         }
    00386         str = paused ? STR_NETWORK_SERVER_MESSAGE_GAME_PAUSED : STR_NETWORK_SERVER_MESSAGE_GAME_UNPAUSED;
    00387       }
    00388
    00389       char buffer[DRAW_STRING_BUFFER];
    00390       GetString(buffer, str, lastof(buffer));
    00391       NetworkTextMessage(NETWORK_ACTION_SERVER_MESSAGE, CC_DEFAULT, false, NULL, buffer);
    00392     } break;
    00393
    00394     default:
    00395       return;
    00396   }
    00397 }
    00398
    00399
    00408 static void CheckPauseHelper(bool pause, PauseMode pm)
    00409 {
    00410   if (pause == ((_pause_mode & pm) != PM_UNPAUSED)) return;
    00411
    00412   DoCommandP(0, pm, pause ? 1 : 0, CMD_PAUSE);
    00413 }
    00414
    00420 static uint NetworkCountActiveClients()
    00421 {
    00422   const NetworkClientSocket *cs;
    00423   uint count = 0;
    00424
    00425   FOR_ALL_CLIENT_SOCKETS(cs) {
    00426     if (cs->status != STATUS_ACTIVE) continue;
    00427     if (!Company::IsValidID(cs->GetInfo()->client_playas)) continue;
    00428     count++;
    00429   }
    00430
    00431   return count;
    00432 }
    00433
    00437 static void CheckMinActiveClients()
    00438 {
    00439   if ((_pause_mode & PM_PAUSED_ERROR) != PM_UNPAUSED ||
    00440       !_network_dedicated ||
    00441       (_settings_client.network.min_active_clients == 0 && (_pause_mode & PM_PAUSED_ACTIVE_CLIENTS) == PM_UNPAUSED)) {
    00442     return;
    00443   }
    00444   CheckPauseHelper(NetworkCountActiveClients() < _settings_client.network.min_active_clients, PM_PAUSED_ACTIVE_CLIENTS);
    00445 }
    00446
    00451 static bool NetworkHasJoiningClient()
    00452 {
    00453   const NetworkClientSocket *cs;
    00454   FOR_ALL_CLIENT_SOCKETS(cs) {
    00455     if (cs->status >= STATUS_AUTHORIZED && cs->status < STATUS_ACTIVE) return true;
    00456   }
    00457
    00458   return false;
    00459 }
    00460
    00464 static void CheckPauseOnJoin()
    00465 {
    00466   if ((_pause_mode & PM_PAUSED_ERROR) != PM_UNPAUSED ||
    00467       (!_settings_client.network.pause_on_join && (_pause_mode & PM_PAUSED_JOIN) == PM_UNPAUSED)) {
    00468     return;
    00469   }
    00470   CheckPauseHelper(NetworkHasJoiningClient(), PM_PAUSED_JOIN);
    00471 }
    00472
    00479 void ParseConnectionString(const char **company, const char **port, char *connection_string)
    00480 {
    00481   bool ipv6 = (strchr(connection_string, ':') != strrchr(connection_string, ':'));
    00482   char *p;
    00483   for (p = connection_string; *p != '\0'; p++) {
    00484     switch (*p) {
    00485       case '[':
    00486         ipv6 = true;
    00487         break;
    00488
    00489       case ']':
    00490         ipv6 = false;
    00491         break;
    00492
    00493       case '#':
    00494         *company = p + 1;
    00495         *p = '\0';
    00496         break;
    00497
    00498       case ':':
    00499         if (ipv6) break;
    00500         *port = p + 1;
    00501         *p = '\0';
    00502         break;
    00503     }
    00504   }
    00505 }
    00506
    00507 /* Creates a new client from a socket
    00508  *   Used both by the server and the client */
    00509 static NetworkClientSocket *NetworkAllocClient(SOCKET s)
    00510 {
    00511   if (_network_server) {
    00512     /* Can we handle a new client? */
    00513     if (_network_clients_connected >= MAX_CLIENTS) return NULL;
    00514     if (_network_game_info.clients_on >= _settings_client.network.max_clients) return NULL;
    00515
    00516     /* Register the login */
    00517     _network_clients_connected++;
    00518   }
    00519
    00520   NetworkClientSocket *cs = new NetworkClientSocket(INVALID_CLIENT_ID);
    00521   cs->sock = s;
    00522   cs->last_frame = _frame_counter;
    00523   cs->last_frame_server = _frame_counter;
    00524
    00525   if (_network_server) {
    00526     cs->client_id = _network_client_id++;
    00527     NetworkClientInfo *ci = new NetworkClientInfo(cs->client_id);
    00528     cs->SetInfo(ci);
    00529     ci->client_playas = COMPANY_INACTIVE_CLIENT;
    00530     ci->join_date = _date;
    00531
    00532     SetWindowDirty(WC_CLIENT_LIST, 0);
    00533   }
    00534
    00535   return cs;
    00536 }
    00537
    00538 /* Close a connection */
    00539 NetworkRecvStatus NetworkCloseClient(NetworkClientSocket *cs, NetworkRecvStatus status)
    00540 {
    00541   assert(status != NETWORK_RECV_STATUS_OKAY);
    00542   /*
    00543    * Sending a message just before leaving the game calls cs->Send_Packets.
    00544    * This might invoke this function, which means that when we close the
    00545    * connection after cs->Send_Packets we will close an already closed
    00546    * connection. This handles that case gracefully without having to make
    00547    * that code any more complex or more aware of the validity of the socket.
    00548    */
    00549   if (cs->sock == INVALID_SOCKET) return status;
    00550
    00551   if (status != NETWORK_RECV_STATUS_CONN_LOST && !cs->HasClientQuit() && _network_server && cs->status >= STATUS_AUTHORIZED) {
    00552     /* We did not receive a leave message from this client... */
    00553     char client_name[NETWORK_CLIENT_NAME_LENGTH];
    00554     NetworkClientSocket *new_cs;
    00555
    00556     NetworkGetClientName(client_name, sizeof(client_name), cs);
    00557
    00558     NetworkTextMessage(NETWORK_ACTION_LEAVE, CC_DEFAULT, false, client_name, NULL, STR_NETWORK_ERROR_CLIENT_CONNECTION_LOST);
    00559
    00560     /* Inform other clients of this... strange leaving ;) */
    00561     FOR_ALL_CLIENT_SOCKETS(new_cs) {
    00562       if (new_cs->status > STATUS_AUTHORIZED && cs != new_cs) {
    00563         SEND_COMMAND(PACKET_SERVER_ERROR_QUIT)(new_cs, cs->client_id, NETWORK_ERROR_CONNECTION_LOST);
    00564       }
    00565     }
    00566   }
    00567
    00568   DEBUG(net, 1, "Closed client connection %d", cs->client_id);
    00569
    00570   if (_network_server) {
    00571     /* We just lost one client :( */
    00572     if (cs->status >= STATUS_AUTHORIZED) _network_game_info.clients_on--;
    00573     _network_clients_connected--;
    00574
    00575     SetWindowDirty(WC_CLIENT_LIST, 0);
    00576   }
    00577
    00578   cs->Send_Packets(true);
    00579
    00580   delete cs->GetInfo();
    00581   delete cs;
    00582
    00583   return status;
    00584 }
    00585
    00586 /* For the server, to accept new clients */
    00587 static void NetworkAcceptClients(SOCKET ls)
    00588 {
    00589   for (;;) {
    00590     struct sockaddr_storage sin;
    00591     memset(&sin, 0, sizeof(sin));
    00592     socklen_t sin_len = sizeof(sin);
    00593     SOCKET s = accept(ls, (struct sockaddr*)&sin, &sin_len);
    00594     if (s == INVALID_SOCKET) return;
    00595
    00596     SetNonBlocking(s); // XXX error handling?
    00597
    00598     NetworkAddress address(sin, sin_len);
    00599     DEBUG(net, 1, "Client connected from %s on frame %d", address.GetHostname(), _frame_counter);
    00600
    00601     SetNoDelay(s); // XXX error handling?
    00602
    00603     /* Check if the client is banned */
    00604     bool banned = false;
    00605     for (char **iter = _network_ban_list.Begin(); iter != _network_ban_list.End(); iter++) {
    00606       banned = address.IsInNetmask(*iter);
    00607       if (banned) {
    00608         Packet p(PACKET_SERVER_BANNED);
    00609         p.PrepareToSend();
    00610
    00611         DEBUG(net, 1, "Banned ip tried to join (%s), refused", *iter);
    00612
    00613         send(s, (const char*)p.buffer, p.size, 0);
    00614         closesocket(s);
    00615         break;
    00616       }
    00617     }
    00618     /* If this client is banned, continue with next client */
    00619     if (banned) continue;
    00620
    00621     NetworkClientSocket *cs = NetworkAllocClient(s);
    00622     if (cs == NULL) {
    00623       /* no more clients allowed?
    00624        * Send to the client that we are full! */
    00625       Packet p(PACKET_SERVER_FULL);
    00626       p.PrepareToSend();
    00627
    00628       send(s, (const char*)p.buffer, p.size, 0);
    00629       closesocket(s);
    00630
    00631       continue;
    00632     }
    00633
    00634     /* a new client has connected. We set him at inactive for now
    00635      *  maybe he is only requesting server-info. Till he has sent a PACKET_CLIENT_MAP_OK
    00636      *  the client stays inactive */
    00637     cs->status = STATUS_INACTIVE;
    00638
    00639     cs->GetInfo()->client_address = address; // Save the IP of the client
    00640   }
    00641 }
    00642
    00643 /* Set up the listen socket for the server */
    00644 static bool NetworkListen()
    00645 {
    00646   assert(_listensockets.Length() == 0);
    00647
    00648   NetworkAddressList addresses;
    00649   GetBindAddresses(&addresses, _settings_client.network.server_port);
    00650
    00651   for (NetworkAddress *address = addresses.Begin(); address != addresses.End(); address++) {
    00652     address->Listen(SOCK_STREAM, &_listensockets);
    00653   }
    00654
    00655   if (_listensockets.Length() == 0) {
    00656     ServerStartError("Could not create listening socket");
    00657     return false;
    00658   }
    00659
    00660   return true;
    00661 }
    00662
    00664 static void InitializeNetworkPools()
    00665 {
    00666   _networkclientsocket_pool.CleanPool();
    00667   _networkclientinfo_pool.CleanPool();
    00668 }
    00669
    00670 /* Close all current connections */
    00671 static void NetworkClose()
    00672 {
    00673   NetworkClientSocket *cs;
    00674
    00675   FOR_ALL_CLIENT_SOCKETS(cs) {
    00676     if (!_network_server) {
    00677       SEND_COMMAND(PACKET_CLIENT_QUIT)();
    00678       cs->Send_Packets();
    00679     }
    00680     NetworkCloseClient(cs, NETWORK_RECV_STATUS_CONN_LOST);
    00681   }
    00682
    00683   if (_network_server) {
    00684     /* We are a server, also close the listensocket */
    00685     for (SocketList::iterator s = _listensockets.Begin(); s != _listensockets.End(); s++) {
    00686       closesocket(s->second);
    00687     }
    00688     _listensockets.Clear();
    00689     DEBUG(net, 1, "[tcp] closed listeners");
    00690   }
    00691
    00692   TCPConnecter::KillAll();
    00693
    00694   _networking = false;
    00695   _network_server = false;
    00696
    00697   NetworkFreeLocalCommandQueue();
    00698
    00699   free(_network_company_states);
    00700   _network_company_states = NULL;
    00701
    00702   InitializeNetworkPools();
    00703 }
    00704
    00705 /* Inits the network (cleans sockets and stuff) */
    00706 static void NetworkInitialize()
    00707 {
    00708   InitializeNetworkPools();
    00709   NetworkUDPInitialize();
    00710
    00711   _sync_frame = 0;
    00712   _network_first_time = true;
    00713
    00714   _network_reconnect = 0;
    00715 }
    00716
    00718 class TCPQueryConnecter : TCPConnecter {
    00719 public:
    00720   TCPQueryConnecter(const NetworkAddress &address) : TCPConnecter(address) {}
    00721
    00722   virtual void OnFailure()
    00723   {
    00724     NetworkDisconnect();
    00725   }
    00726
    00727   virtual void OnConnect(SOCKET s)
    00728   {
    00729     _networking = true;
    00730     NetworkAllocClient(s);
    00731     SEND_COMMAND(PACKET_CLIENT_COMPANY_INFO)();
    00732   }
    00733 };
    00734
    00735 /* Query a server to fetch his game-info
    00736  *  If game_info is true, only the gameinfo is fetched,
    00737  *   else only the client_info is fetched */
    00738 void NetworkTCPQueryServer(NetworkAddress address)
    00739 {
    00740   if (!_network_available) return;
    00741
    00742   NetworkDisconnect();
    00743   NetworkInitialize();
    00744
    00745   new TCPQueryConnecter(address);
    00746 }
    00747
    00748 /* Validates an address entered as a string and adds the server to
    00749  * the list. If you use this function, the games will be marked
    00750  * as manually added. */
    00751 void NetworkAddServer(const char *b)
    00752 {
    00753   if (*b != '\0') {
    00754     const char *port = NULL;
    00755     const char *company = NULL;
    00756     char host[NETWORK_HOSTNAME_LENGTH];
    00757     uint16 rport;
    00758
    00759     strecpy(host, b, lastof(host));
    00760
    00761     strecpy(_settings_client.network.connect_to_ip, b, lastof(_settings_client.network.connect_to_ip));
    00762     rport = NETWORK_DEFAULT_PORT;
    00763
    00764     ParseConnectionString(&company, &port, host);
    00765     if (port != NULL) rport = atoi(port);
    00766
    00767     NetworkUDPQueryServer(NetworkAddress(host, rport), true);
    00768   }
    00769 }
    00770
    00776 void GetBindAddresses(NetworkAddressList *addresses, uint16 port)
    00777 {
    00778   for (char **iter = _network_bind_list.Begin(); iter != _network_bind_list.End(); iter++) {
    00779     *addresses->Append() = NetworkAddress(*iter, port);
    00780   }
    00781
    00782   /* No address, so bind to everything. */
    00783   if (addresses->Length() == 0) {
    00784     *addresses->Append() = NetworkAddress("", port);
    00785   }
    00786 }
    00787
    00788 /* Generates the list of manually added hosts from NetworkGameList and
    00789  * dumps them into the array _network_host_list. This array is needed
    00790  * by the function that generates the config file. */
    00791 void NetworkRebuildHostList()
    00792 {
    00793   _network_host_list.Clear();
    00794
    00795   for (NetworkGameList *item = _network_game_list; item != NULL; item = item->next) {
    00796     if (item->manually) *_network_host_list.Append() = strdup(item->address.GetAddressAsString(false));
    00797   }
    00798 }
    00799
    00801 class TCPClientConnecter : TCPConnecter {
    00802 public:
    00803   TCPClientConnecter(const NetworkAddress &address) : TCPConnecter(address) {}
    00804
    00805   virtual void OnFailure()
    00806   {
    00807     NetworkError(STR_NETWORK_ERROR_NOCONNECTION);
    00808   }
    00809
    00810   virtual void OnConnect(SOCKET s)
    00811   {
    00812     _networking = true;
    00813     NetworkAllocClient(s);
    00814     IConsoleCmdExec("exec scripts/on_client.scr 0");
    00815     NetworkClient_Connected();
    00816   }
    00817 };
    00818
    00819
    00820 /* Used by clients, to connect to a server */
    00821 void NetworkClientConnectGame(NetworkAddress address, CompanyID join_as, const char *join_server_password, const char *join_company_password)
    00822 {
    00823   if (!_network_available) return;
    00824
    00825   if (address.GetPort() == 0) return;
    00826
    00827   strecpy(_settings_client.network.last_host, address.GetHostname(), lastof(_settings_client.network.last_host));
    00828   _settings_client.network.last_port = address.GetPort();
    00829   _network_join_as = join_as;
    00830   _network_join_server_password = join_server_password;
    00831   _network_join_company_password = join_company_password;
    00832
    00833   NetworkDisconnect();
    00834   NetworkInitialize();
    00835
    00836   _network_join_status = NETWORK_JOIN_STATUS_CONNECTING;
    00837   ShowJoinStatusWindow();
    00838
    00839   new TCPClientConnecter(address);
    00840 }
    00841
    00842 static void NetworkInitGameInfo()
    00843 {
    00844   if (StrEmpty(_settings_client.network.server_name)) {
    00845     snprintf(_settings_client.network.server_name, sizeof(_settings_client.network.server_name), "Unnamed Server");
    00846   }
    00847
    00848   /* The server is a client too */
    00849   _network_game_info.clients_on = _network_dedicated ? 0 : 1;
    00850
    00851   NetworkClientInfo *ci = new NetworkClientInfo(CLIENT_ID_SERVER);
    00852   ci->client_playas = _network_dedicated ? COMPANY_SPECTATOR : _local_company;
    00853   /* Give the server a valid IP; banning it is pointless anyways */
    00854   sockaddr_in sock;
    00855   memset(&sock, 0, sizeof(sock));
    00856   sock.sin_family = AF_INET;
    00857   ci->client_address = NetworkAddress((sockaddr*)&sock, sizeof(sock));
    00858
    00859   strecpy(ci->client_name, _settings_client.network.client_name, lastof(ci->client_name));
    00860 }
    00861
    00862 bool NetworkServerStart()
    00863 {
    00864   if (!_network_available) return false;
    00865
    00866   /* Call the pre-scripts */
    00867   IConsoleCmdExec("exec scripts/pre_server.scr 0");
    00868   if (_network_dedicated) IConsoleCmdExec("exec scripts/pre_dedicated.scr 0");
    00869
    00870   NetworkDisconnect();
    00871   NetworkInitialize();
    00872   if (!NetworkListen()) return false;
    00873
    00874   /* Try to start UDP-server */
    00875   _network_udp_server = _udp_server_socket->Listen();
    00876
    00877   _network_company_states = CallocT<NetworkCompanyState>(MAX_COMPANIES);
    00878   _network_server = true;
    00879   _networking = true;
    00880   _frame_counter = 0;
    00881   _frame_counter_server = 0;
    00882   _frame_counter_max = 0;
    00883   _last_sync_frame = 0;
    00884   _network_own_client_id = CLIENT_ID_SERVER;
    00885
    00886   _network_clients_connected = 0;
    00887   _network_company_passworded = 0;
    00888
    00889   NetworkInitGameInfo();
    00890
    00891   /* execute server initialization script */
    00892   IConsoleCmdExec("exec scripts/on_server.scr 0");
    00893   /* if the server is dedicated ... add some other script */
    00894   if (_network_dedicated) IConsoleCmdExec("exec scripts/on_dedicated.scr 0");
    00895
    00896   /* Try to register us to the master server */
    00897   _network_last_advertise_frame = 0;
    00898   _network_need_advertise = true;
    00899   NetworkUDPAdvertise();
    00900   return true;
    00901 }
    00902
    00903 /* The server is rebooting...
    00904  * The only difference with NetworkDisconnect, is the packets that is sent */
    00905 void NetworkReboot()
    00906 {
    00907   if (_network_server) {
    00908     NetworkClientSocket *cs;
    00909     FOR_ALL_CLIENT_SOCKETS(cs) {
    00910       SEND_COMMAND(PACKET_SERVER_NEWGAME)(cs);
    00911       cs->Send_Packets();
    00912     }
    00913   }
    00914
    00915   NetworkClose();
    00916 }
    00917
    00922 void NetworkDisconnect(bool blocking)
    00923 {
    00924   if (_network_server) {
    00925     NetworkClientSocket *cs;
    00926     FOR_ALL_CLIENT_SOCKETS(cs) {
    00927       SEND_COMMAND(PACKET_SERVER_SHUTDOWN)(cs);
    00928       cs->Send_Packets();
    00929     }
    00930   }
    00931
    00932   if (_settings_client.network.server_advertise) NetworkUDPRemoveAdvertise(blocking);
    00933
    00934   DeleteWindowById(WC_NETWORK_STATUS_WINDOW, 0);
    00935
    00936   NetworkClose();
    00937 }
    00938
    00939 /* Receives something from the network */
    00940 static bool NetworkReceive()
    00941 {
    00942   NetworkClientSocket *cs;
    00943   fd_set read_fd, write_fd;
    00944   struct timeval tv;
    00945
    00946   FD_ZERO(&read_fd);
    00947   FD_ZERO(&write_fd);
    00948
    00949   FOR_ALL_CLIENT_SOCKETS(cs) {
    00950     FD_SET(cs->sock, &read_fd);
    00951     FD_SET(cs->sock, &write_fd);
    00952   }
    00953
    00954   /* take care of listener port */
    00955   for (SocketList::iterator s = _listensockets.Begin(); s != _listensockets.End(); s++) {
    00956     FD_SET(s->second, &read_fd);
    00957   }
    00958
    00959   tv.tv_sec = tv.tv_usec = 0; // don't block at all.
    00960 #if !defined(__MORPHOS__) && !defined(__AMIGA__)
    00961   int n = select(FD_SETSIZE, &read_fd, &write_fd, NULL, &tv);
    00962 #else
    00963   int n = WaitSelect(FD_SETSIZE, &read_fd, &write_fd, NULL, &tv, NULL);
    00964 #endif
    00965   if (n == -1 && !_network_server) NetworkError(STR_NETWORK_ERROR_LOSTCONNECTION);
    00966
    00967   /* accept clients.. */
    00968   for (SocketList::iterator s = _listensockets.Begin(); s != _listensockets.End(); s++) {
    00969     if (FD_ISSET(s->second, &read_fd)) NetworkAcceptClients(s->second);
    00970   }
    00971
    00972   /* read stuff from clients */
    00973   FOR_ALL_CLIENT_SOCKETS(cs) {
    00974     cs->writable = !!FD_ISSET(cs->sock, &write_fd);
    00975     if (FD_ISSET(cs->sock, &read_fd)) {
    00976       if (_network_server) {
    00977         NetworkServer_ReadPackets(cs);
    00978       } else {
    00979         NetworkRecvStatus res;
    00980
    00981         /* The client already was quiting! */
    00982         if (cs->HasClientQuit()) return false;
    00983
    00984         res = NetworkClient_ReadPackets(cs);
    00985         if (res != NETWORK_RECV_STATUS_OKAY) {
    00986           /* The client made an error of which we can not recover
    00987            *   close the client and drop back to main menu */
    00988           NetworkClientError(res, cs);
    00989           return false;
    00990         }
    00991       }
    00992     }
    00993   }
    00994   return true;
    00995 }
    00996
    00997 /* This sends all buffered commands (if possible) */
    00998 static void NetworkSend()
    00999 {
    01000   NetworkClientSocket *cs;
    01001   FOR_ALL_CLIENT_SOCKETS(cs) {
    01002     if (cs->writable) {
    01003       cs->Send_Packets();
    01004
    01005       if (cs->status == STATUS_MAP) {
    01006         /* This client is in the middle of a map-send, call the function for that */
    01007         SEND_COMMAND(PACKET_SERVER_MAP)(cs);
    01008       }
    01009     }
    01010   }
    01011 }
    01012
    01013 static bool NetworkDoClientLoop()
    01014 {
    01015   _frame_counter++;
    01016
    01017   NetworkExecuteLocalCommandQueue();
    01018
    01019   StateGameLoop();
    01020
    01021   /* Check if we are in sync! */
    01022   if (_sync_frame != 0) {
    01023     if (_sync_frame == _frame_counter) {
    01024 #ifdef NETWORK_SEND_DOUBLE_SEED
    01025       if (_sync_seed_1 != _random.state[0] || _sync_seed_2 != _random.state[1]) {
    01026 #else
    01027       if (_sync_seed_1 != _random.state[0]) {
    01028 #endif
    01029         NetworkError(STR_NETWORK_ERROR_DESYNC);
    01030         DEBUG(desync, 1, "sync_err: %08x; %02x", _date, _date_fract);
    01031         DEBUG(net, 0, "Sync error detected!");
    01032         NetworkClientError(NETWORK_RECV_STATUS_DESYNC, NetworkClientSocket::Get(0));
    01033         return false;
    01034       }
    01035
    01036       /* If this is the first time we have a sync-frame, we
    01037        *   need to let the server know that we are ready and at the same
    01038        *   frame as he is.. so we can start playing! */
    01039       if (_network_first_time) {
    01040         _network_first_time = false;
    01041         SEND_COMMAND(PACKET_CLIENT_ACK)();
    01042       }
    01043
    01044       _sync_frame = 0;
    01045     } else if (_sync_frame < _frame_counter) {
    01046       DEBUG(net, 1, "Missed frame for sync-test (%d / %d)", _sync_frame, _frame_counter);
    01047       _sync_frame = 0;
    01048     }
    01049   }
    01050
    01051   return true;
    01052 }
    01053
    01054 /* We have to do some UDP checking */
    01055 void NetworkUDPGameLoop()
    01056 {
    01057   _network_content_client.SendReceive();
    01058   TCPConnecter::CheckCallbacks();
    01059   NetworkHTTPSocketHandler::HTTPReceive();
    01060
    01061   if (_network_udp_server) {
    01062     _udp_server_socket->ReceivePackets();
    01063     _udp_master_socket->ReceivePackets();
    01064   } else {
    01065     _udp_client_socket->ReceivePackets();
    01066     if (_network_udp_broadcast > 0) _network_udp_broadcast--;
    01067     NetworkGameListRequery();
    01068   }
    01069 }
    01070
    01071 /* The main loop called from ttd.c
    01072  *  Here we also have to do StateGameLoop if needed! */
    01073 void NetworkGameLoop()
    01074 {
    01075   if (!_networking) return;
    01076
    01077   if (!NetworkReceive()) return;
    01078
    01079   if (_network_server) {
    01080     /* Log the sync state to check for in-syncedness of replays. */
    01081     if (_date_fract == 0) {
    01082       /* We don't want to log multiple times if paused. */
    01083       static Date last_log;
    01084       if (last_log != _date) {
    01085         DEBUG(desync, 1, "sync: %08x; %02x; %08x; %08x", _date, _date_fract, _random.state[0], _random.state[1]);
    01086         last_log = _date;
    01087       }
    01088     }
    01089
    01090 #ifdef DEBUG_DUMP_COMMANDS
    01091     /* Loading of the debug commands from -ddesync>=1 */
    01092     static FILE *f = FioFOpenFile("commands.log", "rb", SAVE_DIR);
    01093     static Date next_date = 0;
    01094     static uint32 next_date_fract;
    01095     static CommandPacket *cp = NULL;
    01096     static bool check_sync_state = false;
    01097     static uint32 sync_state[2];
    01098     if (f == NULL && next_date == 0) {
    01099       DEBUG(net, 0, "Cannot open commands.log");
    01100       next_date = 1;
    01101     }
    01102
    01103     while (f != NULL && !feof(f)) {
    01104       if (_date == next_date && _date_fract == next_date_fract) {
    01105         if (cp != NULL) {
    01106           NetworkSend_Command(cp->tile, cp->p1, cp->p2, cp->cmd & ~CMD_FLAGS_MASK, NULL, cp->text, cp->company);
    01107           DEBUG(net, 0, "injecting: %08x; %02x; %02x; %06x; %08x; %08x; %08x; \"%s\" (%s)", _date, _date_fract, (int)_current_company, cp->tile, cp->p1, cp->p2, cp->cmd, cp->text, GetCommandName(cp->cmd));
    01108           free(cp);
    01109           cp = NULL;
    01110         }
    01111         if (check_sync_state) {
    01112           if (sync_state[0] == _random.state[0] && sync_state[1] == _random.state[1]) {
    01113             DEBUG(net, 0, "sync check: %08x; %02x; match", _date, _date_fract);
    01114           } else {
    01115             DEBUG(net, 0, "sync check: %08x; %02x; mismatch expected {%08x, %08x}, got {%08x, %08x}",
    01116                   _date, _date_fract, sync_state[0], sync_state[1], _random.state[0], _random.state[1]);
    01117             NOT_REACHED();
    01118           }
    01119           check_sync_state = false;
    01120         }
    01121       }
    01122
    01123       if (cp != NULL || check_sync_state) break;
    01124
    01125       char buff[4096];
    01126       if (fgets(buff, lengthof(buff), f) == NULL) break;
    01127
    01128       char *p = buff;
    01129       /* Ignore the "[date time] " part of the message */
    01130       if (*p == '[') {
    01131         p = strchr(p, ']');
    01132         if (p == NULL) break;
    01133         p += 2;
    01134       }
    01135
    01136       if (strncmp(p, "cmd: ", 5) == 0) {
    01137         cp = CallocT<CommandPacket>(1);
    01138         int company;
    01139         int ret = sscanf(p + 5, "%x; %x; %x; %x; %x; %x; %x; \"%[^\"]\"", &next_date, &next_date_fract, &company, &cp->tile, &cp->p1, &cp->p2, &cp->cmd, cp->text);
    01140         /* There are 8 pieces of data to read, however the last is a
    01141          * string that might or might not exist. Ignore it if that
    01142          * string misses because in 99% of the time it's not used. */
    01143         assert(ret == 8 || ret == 7);
    01144         cp->company = (CompanyID)company;
    01145       } else if (strncmp(p, "join: ", 6) == 0) {
    01146         /* Manually insert a pause when joining; this way the client can join at the exact right time. */
    01147         int ret = sscanf(p + 6, "%x; %x", &next_date, &next_date_fract);
    01148         assert(ret == 2);
    01149         DEBUG(net, 0, "injecting pause for join at %08x:%02x; please join when paused", next_date, next_date_fract);
    01150         cp = CallocT<CommandPacket>(1);
    01151         cp->company = COMPANY_SPECTATOR;
    01152         cp->cmd = CMD_PAUSE;
    01153         cp->p1 = PM_PAUSED_NORMAL;
    01154         cp->p2 = 1;
    01155         _ddc_fastforward = false;
    01156       } else if (strncmp(p, "sync: ", 6) == 0) {
    01157         int ret = sscanf(p + 6, "%x; %x; %x; %x", &next_date, &next_date_fract, &sync_state[0], &sync_state[1]);
    01158         assert(ret == 4);
    01159         check_sync_state = true;
    01160       } else if (strncmp(p, "msg: ", 5) == 0 || strncmp(p, "client: ", 8) == 0 ||
    01161             strncmp(p, "load: ", 6) == 0 || strncmp(p, "save: ", 6) == 0) {
    01162         /* A message that is not very important to the log playback, but part of the log. */
    01163       } else {
    01164         /* Can't parse a line; what's wrong here? */
    01165         DEBUG(net, 0, "trying to parse: %s", p);
    01166         NOT_REACHED();
    01167       }
    01168     }
    01169     if (f != NULL && feof(f)) {
    01170       DEBUG(net, 0, "End of commands.log");
    01171       fclose(f);
    01172       f = NULL;
    01173     }
    01174 #endif /* DEBUG_DUMP_COMMANDS */
    01175     if (_frame_counter >= _frame_counter_max) {
    01176       /* Only check for active clients just before we're going to send out
    01177        * the commands so we don't send multiple pause/unpause commands when
    01178        * the frame_freq is more than 1 tick. */
    01179       CheckPauseOnJoin();
    01180       CheckMinActiveClients();
    01181     }
    01182
    01183     bool send_frame = false;
    01184
    01185     /* We first increase the _frame_counter */
    01186     _frame_counter++;
    01187     /* Update max-frame-counter */
    01188     if (_frame_counter > _frame_counter_max) {
    01189       _frame_counter_max = _frame_counter + _settings_client.network.frame_freq;
    01190       send_frame = true;
    01191     }
    01192
    01193     NetworkExecuteLocalCommandQueue();
    01194
    01195     /* Then we make the frame */
    01196     StateGameLoop();
    01197
    01198     _sync_seed_1 = _random.state[0];
    01199 #ifdef NETWORK_SEND_DOUBLE_SEED
    01200     _sync_seed_2 = _random.state[1];
    01201 #endif
    01202
    01203     NetworkServer_Tick(send_frame);
    01204   } else {
    01205     /* Client */
    01206
    01207     /* Make sure we are at the frame were the server is (quick-frames) */
    01208     if (_frame_counter_server > _frame_counter) {
    01209       while (_frame_counter_server > _frame_counter) {
    01210         if (!NetworkDoClientLoop()) break;
    01211       }
    01212     } else {
    01213       /* Else, keep on going till _frame_counter_max */
    01214       if (_frame_counter_max > _frame_counter) NetworkDoClientLoop();
    01215     }
    01216   }
    01217
    01218   NetworkSend();
    01219 }
    01220
    01221 static void NetworkGenerateServerId()
    01222 {
    01223   Md5 checksum;
    01224   uint8 digest[16];
    01225   char hex_output[16 * 2 + 1];
    01226   char coding_string[NETWORK_NAME_LENGTH];
    01227   int di;
    01228
    01229   snprintf(coding_string, sizeof(coding_string), "%d%s", (uint)Random(), "OpenTTD Server ID");
    01230
    01231   /* Generate the MD5 hash */
    01232   checksum.Append((const uint8*)coding_string, strlen(coding_string));
    01233   checksum.Finish(digest);
    01234
    01235   for (di = 0; di < 16; ++di) {
    01236     sprintf(hex_output + di * 2, "%02x", digest[di]);
    01237   }
    01238
    01239   /* _settings_client.network.network_id is our id */
    01240   snprintf(_settings_client.network.network_id, sizeof(_settings_client.network.network_id), "%s", hex_output);
    01241 }
    01242
    01243 void NetworkStartDebugLog(NetworkAddress address)
    01244 {
    01245   extern SOCKET _debug_socket;  // Comes from debug.c
    01246
    01247   DEBUG(net, 0, "Redirecting DEBUG() to %s:%d", address.GetHostname(), address.GetPort());
    01248
    01249   SOCKET s = address.Connect();
    01250   if (s == INVALID_SOCKET) {
    01251     DEBUG(net, 0, "Failed to open socket for redirection DEBUG()");
    01252     return;
    01253   }
    01254
    01255   _debug_socket = s;
    01256
    01257   DEBUG(net, 0, "DEBUG() is now redirected");
    01258 }
    01259
    01261 void NetworkStartUp()
    01262 {
    01263   DEBUG(net, 3, "[core] starting network...");
    01264
    01265   /* Network is available */
    01266   _network_available = NetworkCoreInitialize();
    01267   _network_dedicated = false;
    01268   _network_last_advertise_frame = 0;
    01269   _network_need_advertise = true;
    01270   _network_advertise_retries = 0;
    01271
    01272   /* Generate an server id when there is none yet */
    01273   if (StrEmpty(_settings_client.network.network_id)) NetworkGenerateServerId();
    01274
    01275   memset(&_network_game_info, 0, sizeof(_network_game_info));
    01276
    01277   NetworkInitialize();
    01278   DEBUG(net, 3, "[core] network online, multiplayer available");
    01279   NetworkFindBroadcastIPs(&_broadcast_list);
    01280 }
    01281
    01283 void NetworkShutDown()
    01284 {
    01285   NetworkDisconnect(true);
    01286   NetworkUDPClose();
    01287
    01288   DEBUG(net, 3, "[core] shutting down network");
    01289
    01290   _network_available = false;
    01291
    01292   NetworkCoreShutdown();
    01293 }
    01294
    01299 bool IsNetworkCompatibleVersion(const char *other)
    01300 {
    01301   return strncmp(_openttd_revision, other, NETWORK_REVISION_LENGTH - 1) == 0;
    01302 }
    01303
    01304 #endif /* ENABLE_NETWORK */