network_command.cpp

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00001 /* $Id: network_command.cpp 16273 2009-05-10 21:33:55Z rubidium $ */
00002 
00005 #ifdef ENABLE_NETWORK
00006 
00007 #include "../stdafx.h"
00008 #include "../debug.h"
00009 #include "network_internal.h"
00010 #include "network_client.h"
00011 #include "../command_func.h"
00012 #include "../callback_table.h"
00013 #include "../core/alloc_func.hpp"
00014 #include "../string_func.h"
00015 #include "../company_func.h"
00016 
00018 static CommandPacket *_local_command_queue = NULL;
00019 
00026 void NetworkAddCommandQueue(CommandPacket cp, NetworkClientSocket *cs)
00027 {
00028   CommandPacket *new_cp = MallocT<CommandPacket>(1);
00029   *new_cp = cp;
00030 
00031   CommandPacket **begin = (cs == NULL ? &_local_command_queue : &cs->command_queue);
00032 
00033   if (*begin == NULL) {
00034     *begin = new_cp;
00035   } else {
00036     CommandPacket *c = *begin;
00037     while (c->next != NULL) c = c->next;
00038     c->next = new_cp;
00039   }
00040 }
00041 
00051 void NetworkSend_Command(TileIndex tile, uint32 p1, uint32 p2, uint32 cmd, CommandCallback *callback, const char *text)
00052 {
00053   assert((cmd & CMD_FLAGS_MASK) == 0);
00054 
00055   CommandPacket c;
00056   c.company  = _local_company;
00057   c.next     = NULL;
00058   c.tile     = tile;
00059   c.p1       = p1;
00060   c.p2       = p2;
00061   c.cmd      = cmd;
00062   c.callback = callback;
00063 
00064   strecpy(c.text, (text != NULL) ? text : "", lastof(c.text));
00065 
00066   if (_network_server) {
00067     /* If we are the server, we queue the command in our 'special' queue.
00068      *   In theory, we could execute the command right away, but then the
00069      *   client on the server can do everything 1 tick faster than others.
00070      *   So to keep the game fair, we delay the command with 1 tick
00071      *   which gives about the same speed as most clients.
00072      */
00073     c.frame = _frame_counter_max + 1;
00074     c.my_cmd = true;
00075 
00076     NetworkAddCommandQueue(c);
00077 
00078     /* Only the local client (in this case, the server) gets the callback */
00079     c.callback = 0;
00080     /* And we queue it for delivery to the clients */
00081     NetworkClientSocket *cs;
00082     FOR_ALL_CLIENT_SOCKETS(cs) {
00083       if (cs->status > STATUS_MAP_WAIT) NetworkAddCommandQueue(c, cs);
00084     }
00085     return;
00086   }
00087 
00088   c.frame = 0; // The client can't tell which frame, so just make it 0
00089 
00090   /* Clients send their command to the server and forget all about the packet */
00091   SEND_COMMAND(PACKET_CLIENT_COMMAND)(&c);
00092 }
00093 
00097 void NetworkExecuteLocalCommandQueue()
00098 {
00099   while (_local_command_queue != NULL) {
00100 
00101     /* The queue is always in order, which means
00102      * that the first element will be executed first. */
00103     if (_frame_counter < _local_command_queue->frame) break;
00104 
00105     if (_frame_counter > _local_command_queue->frame) {
00106       /* If we reach here, it means for whatever reason, we've already executed
00107        * past the command we need to execute. */
00108       error("[net] Trying to execute a packet in the past!");
00109     }
00110 
00111     CommandPacket *cp = _local_command_queue;
00112 
00113     /* We can execute this command */
00114     _current_company = cp->company;
00115     cp->cmd |= CMD_NETWORK_COMMAND;
00116     DoCommandP(cp, cp->my_cmd);
00117 
00118     _local_command_queue = _local_command_queue->next;
00119     free(cp);
00120   }
00121 }
00122 
00126 void NetworkFreeLocalCommandQueue()
00127 {
00128   /* Free all queued commands */
00129   while (_local_command_queue != NULL) {
00130     CommandPacket *p = _local_command_queue;
00131     _local_command_queue = _local_command_queue->next;
00132     free(p);
00133   }
00134 }
00135 
00142 const char *NetworkClientSocket::Recv_Command(Packet *p, CommandPacket *cp)
00143 {
00144   cp->company = (CompanyID)p->Recv_uint8();
00145   cp->cmd     = p->Recv_uint32();
00146   cp->p1      = p->Recv_uint32();
00147   cp->p2      = p->Recv_uint32();
00148   cp->tile    = p->Recv_uint32();
00149   p->Recv_string(cp->text, lengthof(cp->text));
00150 
00151   byte callback = p->Recv_uint8();
00152 
00153   if (!IsValidCommand(cp->cmd))               return "invalid command";
00154   if (GetCommandFlags(cp->cmd) & CMD_OFFLINE) return "offline only command";
00155   if ((cp->cmd & CMD_FLAGS_MASK) != 0)        return "invalid command flag";
00156   if (callback > _callback_table_count)       return "invalid callback";
00157 
00158   cp->callback = _callback_table[callback];
00159   return NULL;
00160 }
00161 
00167 void NetworkClientSocket::Send_Command(Packet *p, const CommandPacket *cp)
00168 {
00169   p->Send_uint8 (cp->company);
00170   p->Send_uint32(cp->cmd);
00171   p->Send_uint32(cp->p1);
00172   p->Send_uint32(cp->p2);
00173   p->Send_uint32(cp->tile);
00174   p->Send_string(cp->text);
00175 
00176   byte callback = 0;
00177   while (callback < _callback_table_count && _callback_table[callback] != cp->callback) {
00178     callback++;
00179   }
00180 
00181   if (callback == _callback_table_count) {
00182     DEBUG(net, 0, "Unknown callback. (Pointer: %p) No callback sent", cp->callback);
00183     callback = 0; // _callback_table[0] == NULL
00184   }
00185   p->Send_uint8 (callback);
00186 }
00187 
00188 #endif /* ENABLE_NETWORK */

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