# network_command.cpp

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    00001 /* $Id: network_command.cpp 15299 2009-01-31 20:16:06Z smatz $ */
    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", callback);
    00183     callback = 0; // _callback_table[0] == NULL
    00184   }
    00185   p->Send_uint8 (callback);
    00186 }
    00187
    00188 #endif /* ENABLE_NETWORK */