# network_command.cpp

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    00001 /* $Id: network_command.cpp 17693 2009-10-04 17:16:41Z 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 #ifdef ENABLE_NETWORK
    00013
    00014 #include "../stdafx.h"
    00015 #include "../debug.h"
    00016 #include "network_internal.h"
    00017 #include "network_client.h"
    00018 #include "../command_func.h"
    00019 #include "../callback_table.h"
    00020 #include "../company_func.h"
    00021
    00023 static CommandPacket *_local_command_queue = NULL;
    00024
    00031 void NetworkAddCommandQueue(CommandPacket cp, NetworkClientSocket *cs)
    00032 {
    00033   CommandPacket *new_cp = MallocT<CommandPacket>(1);
    00034   *new_cp = cp;
    00035
    00036   CommandPacket **begin = (cs == NULL ? &_local_command_queue : &cs->command_queue);
    00037
    00038   if (*begin == NULL) {
    00039     *begin = new_cp;
    00040   } else {
    00041     CommandPacket *c = *begin;
    00042     while (c->next != NULL) c = c->next;
    00043     c->next = new_cp;
    00044   }
    00045 }
    00046
    00056 void NetworkSend_Command(TileIndex tile, uint32 p1, uint32 p2, uint32 cmd, CommandCallback *callback, const char *text)
    00057 {
    00058   assert((cmd & CMD_FLAGS_MASK) == 0);
    00059
    00060   CommandPacket c;
    00061   c.company  = _local_company;
    00062   c.next     = NULL;
    00063   c.tile     = tile;
    00064   c.p1       = p1;
    00065   c.p2       = p2;
    00066   c.cmd      = cmd;
    00067   c.callback = callback;
    00068
    00069   strecpy(c.text, (text != NULL) ? text : "", lastof(c.text));
    00070
    00071   if (_network_server) {
    00072     /* If we are the server, we queue the command in our 'special' queue.
    00073      *   In theory, we could execute the command right away, but then the
    00074      *   client on the server can do everything 1 tick faster than others.
    00075      *   So to keep the game fair, we delay the command with 1 tick
    00076      *   which gives about the same speed as most clients.
    00077      */
    00078     c.frame = _frame_counter_max + 1;
    00079     c.my_cmd = true;
    00080
    00081     NetworkAddCommandQueue(c);
    00082
    00083     /* Only the local client (in this case, the server) gets the callback */
    00084     c.callback = 0;
    00085     /* And we queue it for delivery to the clients */
    00086     NetworkClientSocket *cs;
    00087     FOR_ALL_CLIENT_SOCKETS(cs) {
    00088       if (cs->status > STATUS_MAP_WAIT) NetworkAddCommandQueue(c, cs);
    00089     }
    00090     return;
    00091   }
    00092
    00093   c.frame = 0; // The client can't tell which frame, so just make it 0
    00094
    00095   /* Clients send their command to the server and forget all about the packet */
    00096   SEND_COMMAND(PACKET_CLIENT_COMMAND)(&c);
    00097 }
    00098
    00102 void NetworkExecuteLocalCommandQueue()
    00103 {
    00104   while (_local_command_queue != NULL) {
    00105
    00106     /* The queue is always in order, which means
    00107      * that the first element will be executed first. */
    00108     if (_frame_counter < _local_command_queue->frame) break;
    00109
    00110     if (_frame_counter > _local_command_queue->frame) {
    00111       /* If we reach here, it means for whatever reason, we've already executed
    00112        * past the command we need to execute. */
    00113       error("[net] Trying to execute a packet in the past!");
    00114     }
    00115
    00116     CommandPacket *cp = _local_command_queue;
    00117
    00118     /* We can execute this command */
    00119     _current_company = cp->company;
    00120     cp->cmd |= CMD_NETWORK_COMMAND;
    00121     DoCommandP(cp, cp->my_cmd);
    00122
    00123     _local_command_queue = _local_command_queue->next;
    00124     free(cp);
    00125   }
    00126 }
    00127
    00131 void NetworkFreeLocalCommandQueue()
    00132 {
    00133   /* Free all queued commands */
    00134   while (_local_command_queue != NULL) {
    00135     CommandPacket *p = _local_command_queue;
    00136     _local_command_queue = _local_command_queue->next;
    00137     free(p);
    00138   }
    00139 }
    00140
    00147 const char *NetworkClientSocket::Recv_Command(Packet *p, CommandPacket *cp)
    00148 {
    00149   cp->company = (CompanyID)p->Recv_uint8();
    00150   cp->cmd     = p->Recv_uint32();
    00151   cp->p1      = p->Recv_uint32();
    00152   cp->p2      = p->Recv_uint32();
    00153   cp->tile    = p->Recv_uint32();
    00154   p->Recv_string(cp->text, lengthof(cp->text));
    00155
    00156   byte callback = p->Recv_uint8();
    00157
    00158   if (!IsValidCommand(cp->cmd))               return "invalid command";
    00159   if (GetCommandFlags(cp->cmd) & CMD_OFFLINE) return "offline only command";
    00160   if ((cp->cmd & CMD_FLAGS_MASK) != 0)        return "invalid command flag";
    00161   if (callback > _callback_table_count)       return "invalid callback";
    00162
    00163   cp->callback = _callback_table[callback];
    00164   return NULL;
    00165 }
    00166
    00172 void NetworkClientSocket::Send_Command(Packet *p, const CommandPacket *cp)
    00173 {
    00174   p->Send_uint8 (cp->company);
    00175   p->Send_uint32(cp->cmd);
    00176   p->Send_uint32(cp->p1);
    00177   p->Send_uint32(cp->p2);
    00178   p->Send_uint32(cp->tile);
    00179   p->Send_string(cp->text);
    00180
    00181   byte callback = 0;
    00182   while (callback < _callback_table_count && _callback_table[callback] != cp->callback) {
    00183     callback++;
    00184   }
    00185
    00186   if (callback == _callback_table_count) {
    00187     DEBUG(net, 0, "Unknown callback. (Pointer: %p) No callback sent", cp->callback);
    00188     callback = 0; // _callback_table[0] == NULL
    00189   }
    00190   p->Send_uint8 (callback);
    00191 }
    00192
    00193 #endif /* ENABLE_NETWORK */