# network.cpp

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    00001 /* $Id: network.cpp 21184 2010-11-14 12:42:29Z 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
    00254   /* All of these strings start with "***". These characters are interpreted as both left-to-right and
    00255    * right-to-left characters depending on the context. As the next text might be an user's name, the
    00256    * user name's characters will influence the direction of the "***" instead of the language setting
    00257    * of the game. Manually set the direction of the "***" by inserting a text-direction marker. */
    00258   char *msg_ptr = message + Utf8Encode(message, _dynlang.text_dir == TD_LTR ? CHAR_TD_LRM : CHAR_TD_RLM);
    00259   GetString(msg_ptr, strid, lastof(message));
    00260
    00261   DEBUG(desync, 1, "msg: %08x; %02x; %s", _date, _date_fract, message);
    00262   IConsolePrintF(colour, "%s", message);
    00263   NetworkAddChatMessage((TextColour)colour, duration, "%s", message);
    00264 }
    00265
    00266 /* Calculate the frame-lag of a client */
    00267 uint NetworkCalculateLag(const NetworkClientSocket *cs)
    00268 {
    00269   int lag = cs->last_frame_server - cs->last_frame;
    00270   /* This client has missed his ACK packet after 1 DAY_TICKS..
    00271    *  so we increase his lag for every frame that passes!
    00272    * The packet can be out by a max of _net_frame_freq */
    00273   if (cs->last_frame_server + DAY_TICKS + _settings_client.network.frame_freq < _frame_counter)
    00274     lag += _frame_counter - (cs->last_frame_server + DAY_TICKS + _settings_client.network.frame_freq);
    00275
    00276   return lag;
    00277 }
    00278
    00279
    00280 /* There was a non-recoverable error, drop back to the main menu with a nice
    00281  *  error */
    00282 static void NetworkError(StringID error_string)
    00283 {
    00284   _switch_mode = SM_MENU;
    00285   extern StringID _switch_mode_errorstr;
    00286   _switch_mode_errorstr = error_string;
    00287 }
    00288
    00289 static void ServerStartError(const char *error)
    00290 {
    00291   DEBUG(net, 0, "[server] could not start network: %s",error);
    00292   NetworkError(STR_NETWORK_ERROR_SERVER_START);
    00293 }
    00294
    00295 static void NetworkClientError(NetworkRecvStatus res, NetworkClientSocket *cs)
    00296 {
    00297   /* First, send a CLIENT_ERROR to the server, so he knows we are
    00298    *  disconnection (and why!) */
    00299   NetworkErrorCode errorno;
    00300
    00301   /* We just want to close the connection.. */
    00302   if (res == NETWORK_RECV_STATUS_CLOSE_QUERY) {
    00303     cs->NetworkSocketHandler::CloseConnection();
    00304     NetworkCloseClient(cs, res);
    00305     _networking = false;
    00306
    00307     DeleteWindowById(WC_NETWORK_STATUS_WINDOW, 0);
    00308     return;
    00309   }
    00310
    00311   switch (res) {
    00312     case NETWORK_RECV_STATUS_DESYNC:          errorno = NETWORK_ERROR_DESYNC; break;
    00313     case NETWORK_RECV_STATUS_SAVEGAME:        errorno = NETWORK_ERROR_SAVEGAME_FAILED; break;
    00314     case NETWORK_RECV_STATUS_NEWGRF_MISMATCH: errorno = NETWORK_ERROR_NEWGRF_MISMATCH; break;
    00315     default:                                  errorno = NETWORK_ERROR_GENERAL; break;
    00316   }
    00317
    00318   /* This means we fucked up and the server closed the connection */
    00319   if (res != NETWORK_RECV_STATUS_SERVER_ERROR && res != NETWORK_RECV_STATUS_SERVER_FULL &&
    00320       res != NETWORK_RECV_STATUS_SERVER_BANNED) {
    00321     SEND_COMMAND(PACKET_CLIENT_ERROR)(errorno);
    00322   }
    00323
    00324   _switch_mode = SM_MENU;
    00325   NetworkCloseClient(cs, res);
    00326   _networking = false;
    00327 }
    00328
    00334 StringID GetNetworkErrorMsg(NetworkErrorCode err)
    00335 {
    00336   /* List of possible network errors, used by
    00337    * PACKET_SERVER_ERROR and PACKET_CLIENT_ERROR */
    00338   static const StringID network_error_strings[] = {
    00339     STR_NETWORK_ERROR_CLIENT_GENERAL,
    00340     STR_NETWORK_ERROR_CLIENT_DESYNC,
    00341     STR_NETWORK_ERROR_CLIENT_SAVEGAME,
    00342     STR_NETWORK_ERROR_CLIENT_CONNECTION_LOST,
    00343     STR_NETWORK_ERROR_CLIENT_PROTOCOL_ERROR,
    00344     STR_NETWORK_ERROR_CLIENT_NEWGRF_MISMATCH,
    00345     STR_NETWORK_ERROR_CLIENT_NOT_AUTHORIZED,
    00346     STR_NETWORK_ERROR_CLIENT_NOT_EXPECTED,
    00347     STR_NETWORK_ERROR_CLIENT_WRONG_REVISION,
    00348     STR_NETWORK_ERROR_CLIENT_NAME_IN_USE,
    00349     STR_NETWORK_ERROR_CLIENT_WRONG_PASSWORD,
    00350     STR_NETWORK_ERROR_CLIENT_COMPANY_MISMATCH,
    00351     STR_NETWORK_ERROR_CLIENT_KICKED,
    00352     STR_NETWORK_ERROR_CLIENT_CHEATER,
    00353     STR_NETWORK_ERROR_CLIENT_SERVER_FULL
    00354   };
    00355
    00356   if (err >= (ptrdiff_t)lengthof(network_error_strings)) err = NETWORK_ERROR_GENERAL;
    00357
    00358   return network_error_strings[err];
    00359 }
    00360
    00366 void NetworkHandlePauseChange(PauseMode prev_mode, PauseMode changed_mode)
    00367 {
    00368   if (!_networking) return;
    00369
    00370   switch (changed_mode) {
    00371     case PM_PAUSED_NORMAL:
    00372     case PM_PAUSED_JOIN:
    00373     case PM_PAUSED_ACTIVE_CLIENTS: {
    00374       bool changed = ((_pause_mode == PM_UNPAUSED) != (prev_mode == PM_UNPAUSED));
    00375       bool paused = (_pause_mode != PM_UNPAUSED);
    00376       if (!paused && !changed) return;
    00377
    00378       StringID str;
    00379       if (!changed) {
    00380         int i = -1;
    00381         if ((_pause_mode & PM_PAUSED_NORMAL) != PM_UNPAUSED)         SetDParam(++i, STR_NETWORK_SERVER_MESSAGE_GAME_REASON_MANUAL);
    00382         if ((_pause_mode & PM_PAUSED_JOIN) != PM_UNPAUSED)           SetDParam(++i, STR_NETWORK_SERVER_MESSAGE_GAME_REASON_CONNECTING_CLIENTS);
    00383         if ((_pause_mode & PM_PAUSED_ACTIVE_CLIENTS) != PM_UNPAUSED) SetDParam(++i, STR_NETWORK_SERVER_MESSAGE_GAME_REASON_NOT_ENOUGH_PLAYERS);
    00384         str = STR_NETWORK_SERVER_MESSAGE_GAME_STILL_PAUSED_1 + i;
    00385       } else {
    00386         switch (changed_mode) {
    00387           case PM_PAUSED_NORMAL:         SetDParam(0, STR_NETWORK_SERVER_MESSAGE_GAME_REASON_MANUAL); break;
    00388           case PM_PAUSED_JOIN:           SetDParam(0, STR_NETWORK_SERVER_MESSAGE_GAME_REASON_CONNECTING_CLIENTS); break;
    00389           case PM_PAUSED_ACTIVE_CLIENTS: SetDParam(0, STR_NETWORK_SERVER_MESSAGE_GAME_REASON_NOT_ENOUGH_PLAYERS); break;
    00390           default: NOT_REACHED();
    00391         }
    00392         str = paused ? STR_NETWORK_SERVER_MESSAGE_GAME_PAUSED : STR_NETWORK_SERVER_MESSAGE_GAME_UNPAUSED;
    00393       }
    00394
    00395       char buffer[DRAW_STRING_BUFFER];
    00396       GetString(buffer, str, lastof(buffer));
    00397       NetworkTextMessage(NETWORK_ACTION_SERVER_MESSAGE, CC_DEFAULT, false, NULL, buffer);
    00398     } break;
    00399
    00400     default:
    00401       return;
    00402   }
    00403 }
    00404
    00405
    00414 static void CheckPauseHelper(bool pause, PauseMode pm)
    00415 {
    00416   if (pause == ((_pause_mode & pm) != PM_UNPAUSED)) return;
    00417
    00418   DoCommandP(0, pm, pause ? 1 : 0, CMD_PAUSE);
    00419 }
    00420
    00426 static uint NetworkCountActiveClients()
    00427 {
    00428   const NetworkClientSocket *cs;
    00429   uint count = 0;
    00430
    00431   FOR_ALL_CLIENT_SOCKETS(cs) {
    00432     if (cs->status != STATUS_ACTIVE) continue;
    00433     if (!Company::IsValidID(cs->GetInfo()->client_playas)) continue;
    00434     count++;
    00435   }
    00436
    00437   return count;
    00438 }
    00439
    00443 static void CheckMinActiveClients()
    00444 {
    00445   if ((_pause_mode & PM_PAUSED_ERROR) != PM_UNPAUSED ||
    00446       !_network_dedicated ||
    00447       (_settings_client.network.min_active_clients == 0 && (_pause_mode & PM_PAUSED_ACTIVE_CLIENTS) == PM_UNPAUSED)) {
    00448     return;
    00449   }
    00450   CheckPauseHelper(NetworkCountActiveClients() < _settings_client.network.min_active_clients, PM_PAUSED_ACTIVE_CLIENTS);
    00451 }
    00452
    00457 static bool NetworkHasJoiningClient()
    00458 {
    00459   const NetworkClientSocket *cs;
    00460   FOR_ALL_CLIENT_SOCKETS(cs) {
    00461     if (cs->status >= STATUS_AUTHORIZED && cs->status < STATUS_ACTIVE) return true;
    00462   }
    00463
    00464   return false;
    00465 }
    00466
    00470 static void CheckPauseOnJoin()
    00471 {
    00472   if ((_pause_mode & PM_PAUSED_ERROR) != PM_UNPAUSED ||
    00473       (!_settings_client.network.pause_on_join && (_pause_mode & PM_PAUSED_JOIN) == PM_UNPAUSED)) {
    00474     return;
    00475   }
    00476   CheckPauseHelper(NetworkHasJoiningClient(), PM_PAUSED_JOIN);
    00477 }
    00478
    00485 void ParseConnectionString(const char **company, const char **port, char *connection_string)
    00486 {
    00487   bool ipv6 = (strchr(connection_string, ':') != strrchr(connection_string, ':'));
    00488   char *p;
    00489   for (p = connection_string; *p != '\0'; p++) {
    00490     switch (*p) {
    00491       case '[':
    00492         ipv6 = true;
    00493         break;
    00494
    00495       case ']':
    00496         ipv6 = false;
    00497         break;
    00498
    00499       case '#':
    00500         *company = p + 1;
    00501         *p = '\0';
    00502         break;
    00503
    00504       case ':':
    00505         if (ipv6) break;
    00506         *port = p + 1;
    00507         *p = '\0';
    00508         break;
    00509     }
    00510   }
    00511 }
    00512
    00513 /* Creates a new client from a socket
    00514  *   Used both by the server and the client */
    00515 static NetworkClientSocket *NetworkAllocClient(SOCKET s)
    00516 {
    00517   if (_network_server) {
    00518     /* Can we handle a new client? */
    00519     if (_network_clients_connected >= MAX_CLIENTS) return NULL;
    00520     if (_network_game_info.clients_on >= _settings_client.network.max_clients) return NULL;
    00521
    00522     /* Register the login */
    00523     _network_clients_connected++;
    00524   }
    00525
    00526   NetworkClientSocket *cs = new NetworkClientSocket(INVALID_CLIENT_ID);
    00527   cs->sock = s;
    00528   cs->last_frame = _frame_counter;
    00529   cs->last_frame_server = _frame_counter;
    00530
    00531   if (_network_server) {
    00532     cs->client_id = _network_client_id++;
    00533     NetworkClientInfo *ci = new NetworkClientInfo(cs->client_id);
    00534     cs->SetInfo(ci);
    00535     ci->client_playas = COMPANY_INACTIVE_CLIENT;
    00536     ci->join_date = _date;
    00537
    00538     SetWindowDirty(WC_CLIENT_LIST, 0);
    00539   }
    00540
    00541   return cs;
    00542 }
    00543
    00544 /* Close a connection */
    00545 NetworkRecvStatus NetworkCloseClient(NetworkClientSocket *cs, NetworkRecvStatus status)
    00546 {
    00547   assert(status != NETWORK_RECV_STATUS_OKAY);
    00548   /*
    00549    * Sending a message just before leaving the game calls cs->Send_Packets.
    00550    * This might invoke this function, which means that when we close the
    00551    * connection after cs->Send_Packets we will close an already closed
    00552    * connection. This handles that case gracefully without having to make
    00553    * that code any more complex or more aware of the validity of the socket.
    00554    */
    00555   if (cs->sock == INVALID_SOCKET) return status;
    00556
    00557   if (status != NETWORK_RECV_STATUS_CONN_LOST && !cs->HasClientQuit() && _network_server && cs->status >= STATUS_AUTHORIZED) {
    00558     /* We did not receive a leave message from this client... */
    00559     char client_name[NETWORK_CLIENT_NAME_LENGTH];
    00560     NetworkClientSocket *new_cs;
    00561
    00562     NetworkGetClientName(client_name, sizeof(client_name), cs);
    00563
    00564     NetworkTextMessage(NETWORK_ACTION_LEAVE, CC_DEFAULT, false, client_name, NULL, STR_NETWORK_ERROR_CLIENT_CONNECTION_LOST);
    00565
    00566     /* Inform other clients of this... strange leaving ;) */
    00567     FOR_ALL_CLIENT_SOCKETS(new_cs) {
    00568       if (new_cs->status > STATUS_AUTHORIZED && cs != new_cs) {
    00569         SEND_COMMAND(PACKET_SERVER_ERROR_QUIT)(new_cs, cs->client_id, NETWORK_ERROR_CONNECTION_LOST);
    00570       }
    00571     }
    00572   }
    00573
    00574   DEBUG(net, 1, "Closed client connection %d", cs->client_id);
    00575
    00576   if (_network_server) {
    00577     /* We just lost one client :( */
    00578     if (cs->status >= STATUS_AUTHORIZED) _network_game_info.clients_on--;
    00579     _network_clients_connected--;
    00580
    00581     SetWindowDirty(WC_CLIENT_LIST, 0);
    00582   }
    00583
    00584   cs->Send_Packets(true);
    00585
    00586   delete cs->GetInfo();
    00587   delete cs;
    00588
    00589   return status;
    00590 }
    00591
    00592 /* For the server, to accept new clients */
    00593 static void NetworkAcceptClients(SOCKET ls)
    00594 {
    00595   for (;;) {
    00596     struct sockaddr_storage sin;
    00597     memset(&sin, 0, sizeof(sin));
    00598     socklen_t sin_len = sizeof(sin);
    00599     SOCKET s = accept(ls, (struct sockaddr*)&sin, &sin_len);
    00600     if (s == INVALID_SOCKET) return;
    00601
    00602     SetNonBlocking(s); // XXX error handling?
    00603
    00604     NetworkAddress address(sin, sin_len);
    00605     DEBUG(net, 1, "Client connected from %s on frame %d", address.GetHostname(), _frame_counter);
    00606
    00607     SetNoDelay(s); // XXX error handling?
    00608
    00609     /* Check if the client is banned */
    00610     bool banned = false;
    00611     for (char **iter = _network_ban_list.Begin(); iter != _network_ban_list.End(); iter++) {
    00612       banned = address.IsInNetmask(*iter);
    00613       if (banned) {
    00614         Packet p(PACKET_SERVER_BANNED);
    00615         p.PrepareToSend();
    00616
    00617         DEBUG(net, 1, "Banned ip tried to join (%s), refused", *iter);
    00618
    00619         send(s, (const char*)p.buffer, p.size, 0);
    00620         closesocket(s);
    00621         break;
    00622       }
    00623     }
    00624     /* If this client is banned, continue with next client */
    00625     if (banned) continue;
    00626
    00627     NetworkClientSocket *cs = NetworkAllocClient(s);
    00628     if (cs == NULL) {
    00629       /* no more clients allowed?
    00630        * Send to the client that we are full! */
    00631       Packet p(PACKET_SERVER_FULL);
    00632       p.PrepareToSend();
    00633
    00634       send(s, (const char*)p.buffer, p.size, 0);
    00635       closesocket(s);
    00636
    00637       continue;
    00638     }
    00639
    00640     /* a new client has connected. We set him at inactive for now
    00641      *  maybe he is only requesting server-info. Till he has sent a PACKET_CLIENT_MAP_OK
    00642      *  the client stays inactive */
    00643     cs->status = STATUS_INACTIVE;
    00644
    00645     cs->GetInfo()->client_address = address; // Save the IP of the client
    00646   }
    00647 }
    00648
    00649 /* Set up the listen socket for the server */
    00650 static bool NetworkListen()
    00651 {
    00652   assert(_listensockets.Length() == 0);
    00653
    00654   NetworkAddressList addresses;
    00655   GetBindAddresses(&addresses, _settings_client.network.server_port);
    00656
    00657   for (NetworkAddress *address = addresses.Begin(); address != addresses.End(); address++) {
    00658     address->Listen(SOCK_STREAM, &_listensockets);
    00659   }
    00660
    00661   if (_listensockets.Length() == 0) {
    00662     ServerStartError("Could not create listening socket");
    00663     return false;
    00664   }
    00665
    00666   return true;
    00667 }
    00668
    00670 static void InitializeNetworkPools()
    00671 {
    00672   _networkclientsocket_pool.CleanPool();
    00673   _networkclientinfo_pool.CleanPool();
    00674 }
    00675
    00676 /* Close all current connections */
    00677 static void NetworkClose()
    00678 {
    00679   NetworkClientSocket *cs;
    00680
    00681   FOR_ALL_CLIENT_SOCKETS(cs) {
    00682     if (!_network_server) {
    00683       SEND_COMMAND(PACKET_CLIENT_QUIT)();
    00684       cs->Send_Packets(true);
    00685     }
    00686     NetworkCloseClient(cs, NETWORK_RECV_STATUS_CONN_LOST);
    00687   }
    00688
    00689   if (_network_server) {
    00690     /* We are a server, also close the listensocket */
    00691     for (SocketList::iterator s = _listensockets.Begin(); s != _listensockets.End(); s++) {
    00692       closesocket(s->second);
    00693     }
    00694     _listensockets.Clear();
    00695     DEBUG(net, 1, "[tcp] closed listeners");
    00696   }
    00697
    00698   TCPConnecter::KillAll();
    00699
    00700   _networking = false;
    00701   _network_server = false;
    00702
    00703   NetworkFreeLocalCommandQueue();
    00704
    00705   free(_network_company_states);
    00706   _network_company_states = NULL;
    00707
    00708   InitializeNetworkPools();
    00709 }
    00710
    00711 /* Inits the network (cleans sockets and stuff) */
    00712 static void NetworkInitialize()
    00713 {
    00714   InitializeNetworkPools();
    00715   NetworkUDPInitialize();
    00716
    00717   _sync_frame = 0;
    00718   _network_first_time = true;
    00719
    00720   _network_reconnect = 0;
    00721 }
    00722
    00724 class TCPQueryConnecter : TCPConnecter {
    00725 public:
    00726   TCPQueryConnecter(const NetworkAddress &address) : TCPConnecter(address) {}
    00727
    00728   virtual void OnFailure()
    00729   {
    00730     NetworkDisconnect();
    00731   }
    00732
    00733   virtual void OnConnect(SOCKET s)
    00734   {
    00735     _networking = true;
    00736     NetworkAllocClient(s);
    00737     SEND_COMMAND(PACKET_CLIENT_COMPANY_INFO)();
    00738   }
    00739 };
    00740
    00741 /* Query a server to fetch his game-info
    00742  *  If game_info is true, only the gameinfo is fetched,
    00743  *   else only the client_info is fetched */
    00744 void NetworkTCPQueryServer(NetworkAddress address)
    00745 {
    00746   if (!_network_available) return;
    00747
    00748   NetworkDisconnect();
    00749   NetworkInitialize();
    00750
    00751   new TCPQueryConnecter(address);
    00752 }
    00753
    00754 /* Validates an address entered as a string and adds the server to
    00755  * the list. If you use this function, the games will be marked
    00756  * as manually added. */
    00757 void NetworkAddServer(const char *b)
    00758 {
    00759   if (*b != '\0') {
    00760     const char *port = NULL;
    00761     const char *company = NULL;
    00762     char host[NETWORK_HOSTNAME_LENGTH];
    00763     uint16 rport;
    00764
    00765     strecpy(host, b, lastof(host));
    00766
    00767     strecpy(_settings_client.network.connect_to_ip, b, lastof(_settings_client.network.connect_to_ip));
    00768     rport = NETWORK_DEFAULT_PORT;
    00769
    00770     ParseConnectionString(&company, &port, host);
    00771     if (port != NULL) rport = atoi(port);
    00772
    00773     NetworkUDPQueryServer(NetworkAddress(host, rport), true);
    00774   }
    00775 }
    00776
    00782 void GetBindAddresses(NetworkAddressList *addresses, uint16 port)
    00783 {
    00784   for (char **iter = _network_bind_list.Begin(); iter != _network_bind_list.End(); iter++) {
    00785     *addresses->Append() = NetworkAddress(*iter, port);
    00786   }
    00787
    00788   /* No address, so bind to everything. */
    00789   if (addresses->Length() == 0) {
    00790     *addresses->Append() = NetworkAddress("", port);
    00791   }
    00792 }
    00793
    00794 /* Generates the list of manually added hosts from NetworkGameList and
    00795  * dumps them into the array _network_host_list. This array is needed
    00796  * by the function that generates the config file. */
    00797 void NetworkRebuildHostList()
    00798 {
    00799   _network_host_list.Clear();
    00800
    00801   for (NetworkGameList *item = _network_game_list; item != NULL; item = item->next) {
    00802     if (item->manually) *_network_host_list.Append() = strdup(item->address.GetAddressAsString(false));
    00803   }
    00804 }
    00805
    00807 class TCPClientConnecter : TCPConnecter {
    00808 public:
    00809   TCPClientConnecter(const NetworkAddress &address) : TCPConnecter(address) {}
    00810
    00811   virtual void OnFailure()
    00812   {
    00813     NetworkError(STR_NETWORK_ERROR_NOCONNECTION);
    00814   }
    00815
    00816   virtual void OnConnect(SOCKET s)
    00817   {
    00818     _networking = true;
    00819     NetworkAllocClient(s);
    00820     IConsoleCmdExec("exec scripts/on_client.scr 0");
    00821     NetworkClient_Connected();
    00822   }
    00823 };
    00824
    00825
    00826 /* Used by clients, to connect to a server */
    00827 void NetworkClientConnectGame(NetworkAddress address, CompanyID join_as, const char *join_server_password, const char *join_company_password)
    00828 {
    00829   if (!_network_available) return;
    00830
    00831   if (address.GetPort() == 0) return;
    00832
    00833   strecpy(_settings_client.network.last_host, address.GetHostname(), lastof(_settings_client.network.last_host));
    00834   _settings_client.network.last_port = address.GetPort();
    00835   _network_join_as = join_as;
    00836   _network_join_server_password = join_server_password;
    00837   _network_join_company_password = join_company_password;
    00838
    00839   NetworkDisconnect();
    00840   NetworkInitialize();
    00841
    00842   _network_join_status = NETWORK_JOIN_STATUS_CONNECTING;
    00843   ShowJoinStatusWindow();
    00844
    00845   new TCPClientConnecter(address);
    00846 }
    00847
    00848 static void NetworkInitGameInfo()
    00849 {
    00850   if (StrEmpty(_settings_client.network.server_name)) {
    00851     snprintf(_settings_client.network.server_name, sizeof(_settings_client.network.server_name), "Unnamed Server");
    00852   }
    00853
    00854   /* The server is a client too */
    00855   _network_game_info.clients_on = _network_dedicated ? 0 : 1;
    00856
    00857   NetworkClientInfo *ci = new NetworkClientInfo(CLIENT_ID_SERVER);
    00858   ci->client_playas = _network_dedicated ? COMPANY_SPECTATOR : _local_company;
    00859   /* Give the server a valid IP; banning it is pointless anyways */
    00860   sockaddr_in sock;
    00861   memset(&sock, 0, sizeof(sock));
    00862   sock.sin_family = AF_INET;
    00863   ci->client_address = NetworkAddress((sockaddr*)&sock, sizeof(sock));
    00864
    00865   strecpy(ci->client_name, _settings_client.network.client_name, lastof(ci->client_name));
    00866 }
    00867
    00868 bool NetworkServerStart()
    00869 {
    00870   if (!_network_available) return false;
    00871
    00872   /* Call the pre-scripts */
    00873   IConsoleCmdExec("exec scripts/pre_server.scr 0");
    00874   if (_network_dedicated) IConsoleCmdExec("exec scripts/pre_dedicated.scr 0");
    00875
    00876   NetworkDisconnect();
    00877   NetworkInitialize();
    00878   if (!NetworkListen()) return false;
    00879
    00880   /* Try to start UDP-server */
    00881   _network_udp_server = _udp_server_socket->Listen();
    00882
    00883   _network_company_states = CallocT<NetworkCompanyState>(MAX_COMPANIES);
    00884   _network_server = true;
    00885   _networking = true;
    00886   _frame_counter = 0;
    00887   _frame_counter_server = 0;
    00888   _frame_counter_max = 0;
    00889   _last_sync_frame = 0;
    00890   _network_own_client_id = CLIENT_ID_SERVER;
    00891
    00892   _network_clients_connected = 0;
    00893   _network_company_passworded = 0;
    00894
    00895   NetworkInitGameInfo();
    00896
    00897   /* execute server initialization script */
    00898   IConsoleCmdExec("exec scripts/on_server.scr 0");
    00899   /* if the server is dedicated ... add some other script */
    00900   if (_network_dedicated) IConsoleCmdExec("exec scripts/on_dedicated.scr 0");
    00901
    00902   /* Try to register us to the master server */
    00903   _network_last_advertise_frame = 0;
    00904   _network_need_advertise = true;
    00905   NetworkUDPAdvertise();
    00906   return true;
    00907 }
    00908
    00909 /* The server is rebooting...
    00910  * The only difference with NetworkDisconnect, is the packets that is sent */
    00911 void NetworkReboot()
    00912 {
    00913   if (_network_server) {
    00914     NetworkClientSocket *cs;
    00915     FOR_ALL_CLIENT_SOCKETS(cs) {
    00916       SEND_COMMAND(PACKET_SERVER_NEWGAME)(cs);
    00917       cs->Send_Packets();
    00918     }
    00919   }
    00920
    00921   NetworkClose();
    00922 }
    00923
    00928 void NetworkDisconnect(bool blocking)
    00929 {
    00930   if (_network_server) {
    00931     NetworkClientSocket *cs;
    00932     FOR_ALL_CLIENT_SOCKETS(cs) {
    00933       SEND_COMMAND(PACKET_SERVER_SHUTDOWN)(cs);
    00934       cs->Send_Packets();
    00935     }
    00936   }
    00937
    00938   if (_settings_client.network.server_advertise) NetworkUDPRemoveAdvertise(blocking);
    00939
    00940   DeleteWindowById(WC_NETWORK_STATUS_WINDOW, 0);
    00941
    00942   NetworkClose();
    00943
    00944   /* Reinitialize the UDP stack, i.e. close all existing connections. */
    00945   NetworkUDPInitialize();
    00946 }
    00947
    00952 static bool NetworkReceive()
    00953 {
    00954   NetworkClientSocket *cs;
    00955   fd_set read_fd, write_fd;
    00956   struct timeval tv;
    00957
    00958   FD_ZERO(&read_fd);
    00959   FD_ZERO(&write_fd);
    00960
    00961   FOR_ALL_CLIENT_SOCKETS(cs) {
    00962     FD_SET(cs->sock, &read_fd);
    00963     FD_SET(cs->sock, &write_fd);
    00964   }
    00965
    00966   /* take care of listener port */
    00967   for (SocketList::iterator s = _listensockets.Begin(); s != _listensockets.End(); s++) {
    00968     FD_SET(s->second, &read_fd);
    00969   }
    00970
    00971   tv.tv_sec = tv.tv_usec = 0; // don't block at all.
    00972 #if !defined(__MORPHOS__) && !defined(__AMIGA__)
    00973   int n = select(FD_SETSIZE, &read_fd, &write_fd, NULL, &tv);
    00974 #else
    00975   int n = WaitSelect(FD_SETSIZE, &read_fd, &write_fd, NULL, &tv, NULL);
    00976 #endif
    00977   if (n == -1 && !_network_server) NetworkError(STR_NETWORK_ERROR_LOSTCONNECTION);
    00978
    00979   /* accept clients.. */
    00980   for (SocketList::iterator s = _listensockets.Begin(); s != _listensockets.End(); s++) {
    00981     if (FD_ISSET(s->second, &read_fd)) NetworkAcceptClients(s->second);
    00982   }
    00983
    00984   /* read stuff from clients */
    00985   FOR_ALL_CLIENT_SOCKETS(cs) {
    00986     cs->writable = !!FD_ISSET(cs->sock, &write_fd);
    00987     if (FD_ISSET(cs->sock, &read_fd)) {
    00988       if (_network_server) {
    00989         NetworkServer_ReadPackets(cs);
    00990       } else {
    00991         NetworkRecvStatus res;
    00992
    00993         /* The client already was quiting! */
    00994         if (cs->HasClientQuit()) return false;
    00995
    00996         res = NetworkClient_ReadPackets(cs);
    00997         if (res != NETWORK_RECV_STATUS_OKAY) {
    00998           /* The client made an error of which we can not recover
    00999            *   close the client and drop back to main menu */
    01000           NetworkClientError(res, cs);
    01001           return false;
    01002         }
    01003       }
    01004     }
    01005   }
    01006   return _networking;
    01007 }
    01008
    01009 /* This sends all buffered commands (if possible) */
    01010 static void NetworkSend()
    01011 {
    01012   NetworkClientSocket *cs;
    01013   FOR_ALL_CLIENT_SOCKETS(cs) {
    01014     if (cs->writable) {
    01015       if (cs->Send_Packets() && cs->status == STATUS_MAP) {
    01016         /* This client is in the middle of a map-send, call the function for that */
    01017         SEND_COMMAND(PACKET_SERVER_MAP)(cs);
    01018       }
    01019     }
    01020   }
    01021 }
    01022
    01023 static bool NetworkDoClientLoop()
    01024 {
    01025   _frame_counter++;
    01026
    01027   NetworkExecuteLocalCommandQueue();
    01028
    01029   StateGameLoop();
    01030
    01031   /* Check if we are in sync! */
    01032   if (_sync_frame != 0) {
    01033     if (_sync_frame == _frame_counter) {
    01034 #ifdef NETWORK_SEND_DOUBLE_SEED
    01035       if (_sync_seed_1 != _random.state[0] || _sync_seed_2 != _random.state[1]) {
    01036 #else
    01037       if (_sync_seed_1 != _random.state[0]) {
    01038 #endif
    01039         NetworkError(STR_NETWORK_ERROR_DESYNC);
    01040         DEBUG(desync, 1, "sync_err: %08x; %02x", _date, _date_fract);
    01041         DEBUG(net, 0, "Sync error detected!");
    01042         NetworkClientError(NETWORK_RECV_STATUS_DESYNC, NetworkClientSocket::Get(0));
    01043         return false;
    01044       }
    01045
    01046       /* If this is the first time we have a sync-frame, we
    01047        *   need to let the server know that we are ready and at the same
    01048        *   frame as he is.. so we can start playing! */
    01049       if (_network_first_time) {
    01050         _network_first_time = false;
    01051         SEND_COMMAND(PACKET_CLIENT_ACK)();
    01052       }
    01053
    01054       _sync_frame = 0;
    01055     } else if (_sync_frame < _frame_counter) {
    01056       DEBUG(net, 1, "Missed frame for sync-test (%d / %d)", _sync_frame, _frame_counter);
    01057       _sync_frame = 0;
    01058     }
    01059   }
    01060
    01061   return true;
    01062 }
    01063
    01064 /* We have to do some UDP checking */
    01065 void NetworkUDPGameLoop()
    01066 {
    01067   _network_content_client.SendReceive();
    01068   TCPConnecter::CheckCallbacks();
    01069   NetworkHTTPSocketHandler::HTTPReceive();
    01070
    01071   if (_network_udp_server) {
    01072     _udp_server_socket->ReceivePackets();
    01073     _udp_master_socket->ReceivePackets();
    01074   } else {
    01075     _udp_client_socket->ReceivePackets();
    01076     if (_network_udp_broadcast > 0) _network_udp_broadcast--;
    01077     NetworkGameListRequery();
    01078   }
    01079 }
    01080
    01081 /* The main loop called from ttd.c
    01082  *  Here we also have to do StateGameLoop if needed! */
    01083 void NetworkGameLoop()
    01084 {
    01085   if (!_networking) return;
    01086
    01087   if (!NetworkReceive()) return;
    01088
    01089   if (_network_server) {
    01090     /* Log the sync state to check for in-syncedness of replays. */
    01091     if (_date_fract == 0) {
    01092       /* We don't want to log multiple times if paused. */
    01093       static Date last_log;
    01094       if (last_log != _date) {
    01095         DEBUG(desync, 1, "sync: %08x; %02x; %08x; %08x", _date, _date_fract, _random.state[0], _random.state[1]);
    01096         last_log = _date;
    01097       }
    01098     }
    01099
    01100 #ifdef DEBUG_DUMP_COMMANDS
    01101     /* Loading of the debug commands from -ddesync>=1 */
    01102     static FILE *f = FioFOpenFile("commands.log", "rb", SAVE_DIR);
    01103     static Date next_date = 0;
    01104     static uint32 next_date_fract;
    01105     static CommandPacket *cp = NULL;
    01106     static bool check_sync_state = false;
    01107     static uint32 sync_state[2];
    01108     if (f == NULL && next_date == 0) {
    01109       DEBUG(net, 0, "Cannot open commands.log");
    01110       next_date = 1;
    01111     }
    01112
    01113     while (f != NULL && !feof(f)) {
    01114       if (_date == next_date && _date_fract == next_date_fract) {
    01115         if (cp != NULL) {
    01116           NetworkSend_Command(cp->tile, cp->p1, cp->p2, cp->cmd & ~CMD_FLAGS_MASK, NULL, cp->text, cp->company);
    01117           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));
    01118           free(cp);
    01119           cp = NULL;
    01120         }
    01121         if (check_sync_state) {
    01122           if (sync_state[0] == _random.state[0] && sync_state[1] == _random.state[1]) {
    01123             DEBUG(net, 0, "sync check: %08x; %02x; match", _date, _date_fract);
    01124           } else {
    01125             DEBUG(net, 0, "sync check: %08x; %02x; mismatch expected {%08x, %08x}, got {%08x, %08x}",
    01126                   _date, _date_fract, sync_state[0], sync_state[1], _random.state[0], _random.state[1]);
    01127             NOT_REACHED();
    01128           }
    01129           check_sync_state = false;
    01130         }
    01131       }
    01132
    01133       if (cp != NULL || check_sync_state) break;
    01134
    01135       char buff[4096];
    01136       if (fgets(buff, lengthof(buff), f) == NULL) break;
    01137
    01138       char *p = buff;
    01139       /* Ignore the "[date time] " part of the message */
    01140       if (*p == '[') {
    01141         p = strchr(p, ']');
    01142         if (p == NULL) break;
    01143         p += 2;
    01144       }
    01145
    01146       if (strncmp(p, "cmd: ", 5) == 0) {
    01147         cp = CallocT<CommandPacket>(1);
    01148         int company;
    01149         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);
    01150         /* There are 8 pieces of data to read, however the last is a
    01151          * string that might or might not exist. Ignore it if that
    01152          * string misses because in 99% of the time it's not used. */
    01153         assert(ret == 8 || ret == 7);
    01154         cp->company = (CompanyID)company;
    01155       } else if (strncmp(p, "join: ", 6) == 0) {
    01156         /* Manually insert a pause when joining; this way the client can join at the exact right time. */
    01157         int ret = sscanf(p + 6, "%x; %x", &next_date, &next_date_fract);
    01158         assert(ret == 2);
    01159         DEBUG(net, 0, "injecting pause for join at %08x:%02x; please join when paused", next_date, next_date_fract);
    01160         cp = CallocT<CommandPacket>(1);
    01161         cp->company = COMPANY_SPECTATOR;
    01162         cp->cmd = CMD_PAUSE;
    01163         cp->p1 = PM_PAUSED_NORMAL;
    01164         cp->p2 = 1;
    01165         _ddc_fastforward = false;
    01166       } else if (strncmp(p, "sync: ", 6) == 0) {
    01167         int ret = sscanf(p + 6, "%x; %x; %x; %x", &next_date, &next_date_fract, &sync_state[0], &sync_state[1]);
    01168         assert(ret == 4);
    01169         check_sync_state = true;
    01170       } else if (strncmp(p, "msg: ", 5) == 0 || strncmp(p, "client: ", 8) == 0 ||
    01171             strncmp(p, "load: ", 6) == 0 || strncmp(p, "save: ", 6) == 0) {
    01172         /* A message that is not very important to the log playback, but part of the log. */
    01173       } else {
    01174         /* Can't parse a line; what's wrong here? */
    01175         DEBUG(net, 0, "trying to parse: %s", p);
    01176         NOT_REACHED();
    01177       }
    01178     }
    01179     if (f != NULL && feof(f)) {
    01180       DEBUG(net, 0, "End of commands.log");
    01181       fclose(f);
    01182       f = NULL;
    01183     }
    01184 #endif /* DEBUG_DUMP_COMMANDS */
    01185     if (_frame_counter >= _frame_counter_max) {
    01186       /* Only check for active clients just before we're going to send out
    01187        * the commands so we don't send multiple pause/unpause commands when
    01188        * the frame_freq is more than 1 tick. */
    01189       CheckPauseOnJoin();
    01190       CheckMinActiveClients();
    01191     }
    01192
    01193     bool send_frame = false;
    01194
    01195     /* We first increase the _frame_counter */
    01196     _frame_counter++;
    01197     /* Update max-frame-counter */
    01198     if (_frame_counter > _frame_counter_max) {
    01199       _frame_counter_max = _frame_counter + _settings_client.network.frame_freq;
    01200       send_frame = true;
    01201     }
    01202
    01203     NetworkExecuteLocalCommandQueue();
    01204
    01205     /* Then we make the frame */
    01206     StateGameLoop();
    01207
    01208     _sync_seed_1 = _random.state[0];
    01209 #ifdef NETWORK_SEND_DOUBLE_SEED
    01210     _sync_seed_2 = _random.state[1];
    01211 #endif
    01212
    01213     NetworkServer_Tick(send_frame);
    01214   } else {
    01215     /* Client */
    01216
    01217     /* Make sure we are at the frame were the server is (quick-frames) */
    01218     if (_frame_counter_server > _frame_counter) {
    01219       while (_frame_counter_server > _frame_counter) {
    01220         if (!NetworkDoClientLoop()) break;
    01221       }
    01222     } else {
    01223       /* Else, keep on going till _frame_counter_max */
    01224       if (_frame_counter_max > _frame_counter) NetworkDoClientLoop();
    01225     }
    01226   }
    01227
    01228   NetworkSend();
    01229 }
    01230
    01231 static void NetworkGenerateServerId()
    01232 {
    01233   Md5 checksum;
    01234   uint8 digest[16];
    01235   char hex_output[16 * 2 + 1];
    01236   char coding_string[NETWORK_NAME_LENGTH];
    01237   int di;
    01238
    01239   snprintf(coding_string, sizeof(coding_string), "%d%s", (uint)Random(), "OpenTTD Server ID");
    01240
    01241   /* Generate the MD5 hash */
    01242   checksum.Append((const uint8*)coding_string, strlen(coding_string));
    01243   checksum.Finish(digest);
    01244
    01245   for (di = 0; di < 16; ++di) {
    01246     sprintf(hex_output + di * 2, "%02x", digest[di]);
    01247   }
    01248
    01249   /* _settings_client.network.network_id is our id */
    01250   snprintf(_settings_client.network.network_id, sizeof(_settings_client.network.network_id), "%s", hex_output);
    01251 }
    01252
    01253 void NetworkStartDebugLog(NetworkAddress address)
    01254 {
    01255   extern SOCKET _debug_socket;  // Comes from debug.c
    01256
    01257   DEBUG(net, 0, "Redirecting DEBUG() to %s:%d", address.GetHostname(), address.GetPort());
    01258
    01259   SOCKET s = address.Connect();
    01260   if (s == INVALID_SOCKET) {
    01261     DEBUG(net, 0, "Failed to open socket for redirection DEBUG()");
    01262     return;
    01263   }
    01264
    01265   _debug_socket = s;
    01266
    01267   DEBUG(net, 0, "DEBUG() is now redirected");
    01268 }
    01269
    01271 void NetworkStartUp()
    01272 {
    01273   DEBUG(net, 3, "[core] starting network...");
    01274
    01275   /* Network is available */
    01276   _network_available = NetworkCoreInitialize();
    01277   _network_dedicated = false;
    01278   _network_last_advertise_frame = 0;
    01279   _network_need_advertise = true;
    01280   _network_advertise_retries = 0;
    01281
    01282   /* Generate an server id when there is none yet */
    01283   if (StrEmpty(_settings_client.network.network_id)) NetworkGenerateServerId();
    01284
    01285   memset(&_network_game_info, 0, sizeof(_network_game_info));
    01286
    01287   NetworkInitialize();
    01288   DEBUG(net, 3, "[core] network online, multiplayer available");
    01289   NetworkFindBroadcastIPs(&_broadcast_list);
    01290 }
    01291
    01293 void NetworkShutDown()
    01294 {
    01295   NetworkDisconnect(true);
    01296   NetworkUDPClose();
    01297
    01298   DEBUG(net, 3, "[core] shutting down network");
    01299
    01300   _network_available = false;
    01301
    01302   NetworkCoreShutdown();
    01303 }
    01304
    01309 bool IsNetworkCompatibleVersion(const char *other)
    01310 {
    01311   return strncmp(_openttd_revision, other, NETWORK_REVISION_LENGTH - 1) == 0;
    01312 }
    01313
    01314 #endif /* ENABLE_NETWORK */