network_command.cpp

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00001 /* $Id$ */
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 #ifdef ENABLE_NETWORK
00013 
00014 #include "../stdafx.h"
00015 #include "network_admin.h"
00016 #include "network_client.h"
00017 #include "network_server.h"
00018 #include "../command_func.h"
00019 #include "../company_func.h"
00020 #include "../settings_type.h"
00021 
00023 static CommandCallback * const _callback_table[] = {
00024   /* 0x00 */ NULL,
00025   /* 0x01 */ CcBuildPrimaryVehicle,
00026   /* 0x02 */ CcBuildAirport,
00027   /* 0x03 */ CcBuildBridge,
00028   /* 0x04 */ CcBuildCanal,
00029   /* 0x05 */ CcBuildDocks,
00030   /* 0x06 */ CcFoundTown,
00031   /* 0x07 */ CcBuildRoadTunnel,
00032   /* 0x08 */ CcBuildRailTunnel,
00033   /* 0x09 */ CcBuildWagon,
00034   /* 0x0A */ CcRoadDepot,
00035   /* 0x0B */ CcRailDepot,
00036   /* 0x0C */ CcPlaceSign,
00037   /* 0x0D */ CcPlaySound10,
00038   /* 0x0E */ CcPlaySound1D,
00039   /* 0x0F */ CcPlaySound1E,
00040   /* 0x10 */ CcStation,
00041   /* 0x11 */ CcTerraform,
00042   /* 0x12 */ CcAI,
00043   /* 0x13 */ CcCloneVehicle,
00044   /* 0x14 */ CcGiveMoney,
00045   /* 0x15 */ CcCreateGroup,
00046   /* 0x16 */ CcFoundRandomTown,
00047   /* 0x17 */ CcRoadStop,
00048   /* 0x18 */ CcBuildIndustry,
00049   /* 0x19 */ CcStartStopVehicle,
00050 };
00051 
00057 void CommandQueue::Append(CommandPacket *p)
00058 {
00059   CommandPacket *add = MallocT<CommandPacket>(1);
00060   *add = *p;
00061   add->next = NULL;
00062   if (this->first == NULL) {
00063     this->first = add;
00064   } else {
00065     this->last->next = add;
00066   }
00067   this->last = add;
00068   this->count++;
00069 }
00070 
00076 CommandPacket *CommandQueue::Pop(bool ignore_paused)
00077 {
00078   CommandPacket **prev = &this->first;
00079   CommandPacket *ret = this->first;
00080   CommandPacket *prev_item = NULL;
00081   if (ignore_paused && _pause_mode != PM_UNPAUSED) {
00082     while (ret != NULL && !IsCommandAllowedWhilePaused(ret->cmd)) {
00083       prev_item = ret;
00084       prev = &ret->next;
00085       ret = ret->next;
00086     }
00087   }
00088   if (ret != NULL) {
00089     if (ret == this->last) this->last = prev_item;
00090     *prev = ret->next;
00091     this->count--;
00092   }
00093   return ret;
00094 }
00095 
00101 CommandPacket *CommandQueue::Peek(bool ignore_paused)
00102 {
00103   if (!ignore_paused || _pause_mode == PM_UNPAUSED) return this->first;
00104 
00105   for (CommandPacket *p = this->first; p != NULL; p = p->next) {
00106     if (IsCommandAllowedWhilePaused(p->cmd)) return p;
00107   }
00108   return NULL;
00109 }
00110 
00112 void CommandQueue::Free()
00113 {
00114   CommandPacket *cp;
00115   while ((cp = this->Pop()) != NULL) {
00116     free(cp);
00117   }
00118   assert(this->count == 0);
00119 }
00120 
00122 static CommandQueue _local_wait_queue;
00124 static CommandQueue _local_execution_queue;
00125 
00136 void NetworkSendCommand(TileIndex tile, uint32 p1, uint32 p2, uint32 cmd, CommandCallback *callback, const char *text, CompanyID company)
00137 {
00138   assert((cmd & CMD_FLAGS_MASK) == 0);
00139 
00140   CommandPacket c;
00141   c.company  = company;
00142   c.tile     = tile;
00143   c.p1       = p1;
00144   c.p2       = p2;
00145   c.cmd      = cmd;
00146   c.callback = callback;
00147 
00148   strecpy(c.text, (text != NULL) ? text : "", lastof(c.text));
00149 
00150   if (_network_server) {
00151     /* If we are the server, we queue the command in our 'special' queue.
00152      *   In theory, we could execute the command right away, but then the
00153      *   client on the server can do everything 1 tick faster than others.
00154      *   So to keep the game fair, we delay the command with 1 tick
00155      *   which gives about the same speed as most clients.
00156      */
00157     c.frame = _frame_counter_max + 1;
00158     c.my_cmd = true;
00159 
00160     _local_wait_queue.Append(&c);
00161     return;
00162   }
00163 
00164   c.frame = 0; // The client can't tell which frame, so just make it 0
00165 
00166   /* Clients send their command to the server and forget all about the packet */
00167   MyClient::SendCommand(&c);
00168 }
00169 
00179 void NetworkSyncCommandQueue(NetworkClientSocket *cs)
00180 {
00181   for (CommandPacket *p = _local_execution_queue.Peek(); p != NULL; p = p->next) {
00182     CommandPacket c = *p;
00183     c.callback = 0;
00184     cs->outgoing_queue.Append(&c);
00185   }
00186 }
00187 
00191 void NetworkExecuteLocalCommandQueue()
00192 {
00193   assert(IsLocalCompany());
00194 
00195   CommandQueue &queue = (_network_server ? _local_execution_queue : ClientNetworkGameSocketHandler::my_client->incoming_queue);
00196 
00197   CommandPacket *cp;
00198   while ((cp = queue.Peek()) != NULL) {
00199     /* The queue is always in order, which means
00200      * that the first element will be executed first. */
00201     if (_frame_counter < cp->frame) break;
00202 
00203     if (_frame_counter > cp->frame) {
00204       /* If we reach here, it means for whatever reason, we've already executed
00205        * past the command we need to execute. */
00206       error("[net] Trying to execute a packet in the past!");
00207     }
00208 
00209     /* We can execute this command */
00210     _current_company = cp->company;
00211     cp->cmd |= CMD_NETWORK_COMMAND;
00212     DoCommandP(cp, cp->my_cmd);
00213 
00214     queue.Pop();
00215     free(cp);
00216   }
00217 
00218   /* Local company may have changed, so we should not restore the old value */
00219   _current_company = _local_company;
00220 }
00221 
00225 void NetworkFreeLocalCommandQueue()
00226 {
00227   _local_wait_queue.Free();
00228   _local_execution_queue.Free();
00229 }
00230 
00236 static void DistributeCommandPacket(CommandPacket cp, const NetworkClientSocket *owner)
00237 {
00238   CommandCallback *callback = cp.callback;
00239   cp.frame = _frame_counter_max + 1;
00240 
00241   NetworkClientSocket *cs;
00242   FOR_ALL_CLIENT_SOCKETS(cs) {
00243     if (cs->status >= NetworkClientSocket::STATUS_MAP) {
00244       /* Callbacks are only send back to the client who sent them in the
00245        *  first place. This filters that out. */
00246       cp.callback = (cs != owner) ? NULL : callback;
00247       cp.my_cmd = (cs == owner);
00248       cs->outgoing_queue.Append(&cp);
00249     }
00250   }
00251 
00252   cp.callback = (cs != owner) ? NULL : callback;
00253   cp.my_cmd = (cs == owner);
00254   _local_execution_queue.Append(&cp);
00255 }
00256 
00262 static void DistributeQueue(CommandQueue *queue, const NetworkClientSocket *owner)
00263 {
00264   int to_go = _settings_client.network.commands_per_frame;
00265 
00266   CommandPacket *cp;
00267   while (--to_go >= 0 && (cp = queue->Pop(true)) != NULL) {
00268     DistributeCommandPacket(*cp, owner);
00269     NetworkAdminCmdLogging(owner, cp);
00270     free(cp);
00271   }
00272 }
00273 
00275 void NetworkDistributeCommands()
00276 {
00277   /* First send the server's commands. */
00278   DistributeQueue(&_local_wait_queue, NULL);
00279 
00280   /* Then send the queues of the others. */
00281   NetworkClientSocket *cs;
00282   FOR_ALL_CLIENT_SOCKETS(cs) {
00283     DistributeQueue(&cs->incoming_queue, cs);
00284   }
00285 }
00286 
00293 const char *NetworkGameSocketHandler::ReceiveCommand(Packet *p, CommandPacket *cp)
00294 {
00295   cp->company = (CompanyID)p->Recv_uint8();
00296   cp->cmd     = p->Recv_uint32();
00297   cp->p1      = p->Recv_uint32();
00298   cp->p2      = p->Recv_uint32();
00299   cp->tile    = p->Recv_uint32();
00300   p->Recv_string(cp->text, lengthof(cp->text));
00301 
00302   byte callback = p->Recv_uint8();
00303 
00304   if (!IsValidCommand(cp->cmd))               return "invalid command";
00305   if (GetCommandFlags(cp->cmd) & CMD_OFFLINE) return "offline only command";
00306   if ((cp->cmd & CMD_FLAGS_MASK) != 0)        return "invalid command flag";
00307   if (callback >= lengthof(_callback_table))  return "invalid callback";
00308 
00309   cp->callback = _callback_table[callback];
00310   return NULL;
00311 }
00312 
00318 void NetworkGameSocketHandler::SendCommand(Packet *p, const CommandPacket *cp)
00319 {
00320   p->Send_uint8 (cp->company);
00321   p->Send_uint32(cp->cmd);
00322   p->Send_uint32(cp->p1);
00323   p->Send_uint32(cp->p2);
00324   p->Send_uint32(cp->tile);
00325   p->Send_string(cp->text);
00326 
00327   byte callback = 0;
00328   while (callback < lengthof(_callback_table) && _callback_table[callback] != cp->callback) {
00329     callback++;
00330   }
00331 
00332   if (callback == lengthof(_callback_table)) {
00333     DEBUG(net, 0, "Unknown callback. (Pointer: %p) No callback sent", cp->callback);
00334     callback = 0; // _callback_table[0] == NULL
00335   }
00336   p->Send_uint8 (callback);
00337 }
00338 
00339 #endif /* ENABLE_NETWORK */