ref: 1bcdb39fd1b273941c493be9259b44c8560b5d16
dir: /src/heretic/d_net.c/
// Emacs style mode select -*- C++ -*-
//-----------------------------------------------------------------------------
//
// Copyright(C) 1993-1996 Id Software, Inc.
// Copyright(C) 1993-2008 Raven Software
// Copyright(C) 2008 Simon Howard
//
// This program 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; either version 2
// of the License, or (at your option) any later version.
//
// This program 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. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
// 02111-1307, USA.
//
//-----------------------------------------------------------------------------
// d_net.c
// This version has the fixed ticdup code
#include <stdlib.h>
#include "doomdef.h"
#include "doomkeys.h"
#include "i_system.h"
#include "i_timer.h"
#include "i_video.h"
#define NCMD_EXIT 0x80000000
#define NCMD_RETRANSMIT 0x40000000
#define NCMD_SETUP 0x20000000
#define NCMD_KILL 0x10000000 // kill game
#define NCMD_CHECKSUM 0x0fffffff
doomcom_t *doomcom;
doomdata_t *netbuffer; // points inside doomcom
/*
==============================================================================
NETWORKING
gametic is the tic about to (or currently being) run
maketic is the tick that hasn't had control made for it yet
nettics[] has the maketics for all players
a gametic cannot be run until nettics[] > gametic for all players
==============================================================================
*/
#define RESENDCOUNT 10
#define PL_DRONE 0x80 // bit flag in doomdata->player
ticcmd_t localcmds[BACKUPTICS];
ticcmd_t netcmds[MAXPLAYERS][BACKUPTICS];
int nettics[MAXNETNODES];
boolean nodeingame[MAXNETNODES]; // set false as nodes leave game
boolean remoteresend[MAXNETNODES]; // set when local needs tics
int resendto[MAXNETNODES]; // set when remote needs tics
int resendcount[MAXNETNODES];
int nodeforplayer[MAXPLAYERS];
int maketic;
int lastnettic, skiptics;
int ticdup;
int maxsend; // BACKUPTICS/(2*ticdup)-1
void D_ProcessEvents(void);
void G_BuildTiccmd(ticcmd_t * cmd);
void D_DoAdvanceDemo(void);
boolean reboundpacket;
doomdata_t reboundstore;
int NetbufferSize(void)
{
return (int) &(((doomdata_t *) 0)->cmds[netbuffer->numtics]);
}
unsigned NetbufferChecksum(void)
{
unsigned c;
int i, l;
c = 0x1234567;
#if defined(NeXT) || defined(NORMALUNIX)
return 0; // byte order problems
#endif
l = (NetbufferSize() - (int) &(((doomdata_t *) 0)->retransmitfrom)) / 4;
for (i = 0; i < l; i++)
c += ((unsigned *) &netbuffer->retransmitfrom)[i] * (i + 1);
return c & NCMD_CHECKSUM;
}
int ExpandTics(int low)
{
int delta;
delta = low - (maketic & 0xff);
if (delta >= -64 && delta <= 64)
return (maketic & ~0xff) + low;
if (delta > 64)
return (maketic & ~0xff) - 256 + low;
if (delta < -64)
return (maketic & ~0xff) + 256 + low;
I_Error("ExpandTics: strange value %i at maketic %i", low, maketic);
return 0;
}
//============================================================================
/*
==============
=
= HSendPacket
=
==============
*/
void HSendPacket(int node, int flags)
{
netbuffer->checksum = NetbufferChecksum() | flags;
if (!node)
{
reboundstore = *netbuffer;
reboundpacket = true;
return;
}
if (demoplayback)
return;
if (!netgame)
I_Error("Tried to transmit to another node");
doomcom->command = CMD_SEND;
doomcom->remotenode = node;
doomcom->datalength = NetbufferSize();
if (debugfile)
{
int i;
int realretrans;
if (netbuffer->checksum & NCMD_RETRANSMIT)
realretrans = ExpandTics(netbuffer->retransmitfrom);
else
realretrans = -1;
fprintf(debugfile, "send (%i + %i, R %i) [%i] ",
ExpandTics(netbuffer->starttic), netbuffer->numtics,
realretrans, doomcom->datalength);
for (i = 0; i < doomcom->datalength; i++)
fprintf(debugfile, "%i ", ((byte *) netbuffer)[i]);
fprintf(debugfile, "\n");
}
#ifdef I_NET
I_NetCmd();
#endif
}
/*
==============
=
= HGetPacket
=
= Returns false if no packet is waiting
=
==============
*/
boolean HGetPacket(void)
{
if (reboundpacket)
{
*netbuffer = reboundstore;
doomcom->remotenode = 0;
reboundpacket = false;
return true;
}
if (!netgame)
return false;
if (demoplayback)
return false;
doomcom->command = CMD_GET;
#ifdef I_NET
I_NetCmd();
#endif
if (doomcom->remotenode == -1)
return false;
if (doomcom->datalength != NetbufferSize())
{
if (debugfile)
fprintf(debugfile, "bad packet length %i\n", doomcom->datalength);
return false;
}
if (NetbufferChecksum() != (netbuffer->checksum & NCMD_CHECKSUM))
{
if (debugfile)
fprintf(debugfile, "bad packet checksum\n");
return false;
}
if (debugfile)
{
int realretrans;
int i;
if (netbuffer->checksum & NCMD_SETUP)
fprintf(debugfile, "setup packet\n");
else
{
if (netbuffer->checksum & NCMD_RETRANSMIT)
realretrans = ExpandTics(netbuffer->retransmitfrom);
else
realretrans = -1;
fprintf(debugfile, "get %i = (%i + %i, R %i)[%i] ",
doomcom->remotenode, ExpandTics(netbuffer->starttic),
netbuffer->numtics, realretrans, doomcom->datalength);
for (i = 0; i < doomcom->datalength; i++)
fprintf(debugfile, "%i ", ((byte *) netbuffer)[i]);
fprintf(debugfile, "\n");
}
}
return true;
}
/*
===================
=
= GetPackets
=
===================
*/
char exitmsg[80];
void GetPackets(void)
{
int netconsole;
int netnode;
ticcmd_t *src, *dest;
int realend;
int realstart;
while (HGetPacket())
{
if (netbuffer->checksum & NCMD_SETUP)
continue; // extra setup packet
netconsole = netbuffer->player & ~PL_DRONE;
netnode = doomcom->remotenode;
//
// to save bytes, only the low byte of tic numbers are sent
// Figure out what the rest of the bytes are
//
realstart = ExpandTics(netbuffer->starttic);
realend = (realstart + netbuffer->numtics);
//
// check for exiting the game
//
if (netbuffer->checksum & NCMD_EXIT)
{
if (!nodeingame[netnode])
continue;
nodeingame[netnode] = false;
playeringame[netconsole] = false;
strcpy(exitmsg, "PLAYER 1 LEFT THE GAME");
exitmsg[7] += netconsole;
players[consoleplayer].message = exitmsg;
// if (demorecording)
// G_CheckDemoStatus ();
continue;
}
//
// check for a remote game kill
//
if (netbuffer->checksum & NCMD_KILL)
I_Error("Killed by network driver");
nodeforplayer[netconsole] = netnode;
//
// check for retransmit request
//
if (resendcount[netnode] <= 0
&& (netbuffer->checksum & NCMD_RETRANSMIT))
{
resendto[netnode] = ExpandTics(netbuffer->retransmitfrom);
if (debugfile)
fprintf(debugfile, "retransmit from %i\n", resendto[netnode]);
resendcount[netnode] = RESENDCOUNT;
}
else
resendcount[netnode]--;
//
// check for out of order / duplicated packet
//
if (realend == nettics[netnode])
continue;
if (realend < nettics[netnode])
{
if (debugfile)
fprintf(debugfile, "out of order packet (%i + %i)\n",
realstart, netbuffer->numtics);
continue;
}
//
// check for a missed packet
//
if (realstart > nettics[netnode])
{
// stop processing until the other system resends the missed tics
if (debugfile)
fprintf(debugfile, "missed tics from %i (%i - %i)\n", netnode,
realstart, nettics[netnode]);
remoteresend[netnode] = true;
continue;
}
//
// update command store from the packet
//
{
int start;
remoteresend[netnode] = false;
start = nettics[netnode] - realstart;
src = &netbuffer->cmds[start];
while (nettics[netnode] < realend)
{
dest = &netcmds[netconsole][nettics[netnode] % BACKUPTICS];
nettics[netnode]++;
*dest = *src;
src++;
}
}
}
}
/*
=============
=
= NetUpdate
=
= Builds ticcmds for console player
= sends out a packet
=============
*/
int gametime;
void NetUpdate(void)
{
int nowtime;
int newtics;
int i, j;
int realstart;
int gameticdiv;
//
// check time
//
nowtime = I_GetTime() / ticdup;
newtics = nowtime - gametime;
gametime = nowtime;
if (newtics <= 0) // nothing new to update
goto listen;
if (skiptics <= newtics)
{
newtics -= skiptics;
skiptics = 0;
}
else
{
skiptics -= newtics;
newtics = 0;
}
netbuffer->player = consoleplayer;
//
// build new ticcmds for console player
//
gameticdiv = gametic / ticdup;
for (i = 0; i < newtics; i++)
{
I_StartTic();
D_ProcessEvents();
if (maketic - gameticdiv >= BACKUPTICS / 2 - 1)
break; // can't hold any more
//printf ("mk:%i ",maketic);
G_BuildTiccmd(&localcmds[maketic % BACKUPTICS]);
maketic++;
}
if (singletics)
return; // singletic update is syncronous
//
// send the packet to the other nodes
//
for (i = 0; i < doomcom->numnodes; i++)
if (nodeingame[i])
{
netbuffer->starttic = realstart = resendto[i];
netbuffer->numtics = maketic - realstart;
if (netbuffer->numtics > BACKUPTICS)
I_Error("NetUpdate: netbuffer->numtics > BACKUPTICS");
resendto[i] = maketic - doomcom->extratics;
for (j = 0; j < netbuffer->numtics; j++)
netbuffer->cmds[j] = localcmds[(realstart + j) % BACKUPTICS];
if (remoteresend[i])
{
netbuffer->retransmitfrom = nettics[i];
HSendPacket(i, NCMD_RETRANSMIT);
}
else
{
netbuffer->retransmitfrom = 0;
HSendPacket(i, 0);
}
}
//
// listen for other packets
//
listen:
GetPackets();
}
/*
=====================
=
= CheckAbort
=
=====================
*/
void CheckAbort(void)
{
event_t *ev;
int stoptic;
stoptic = I_GetTime() + 2;
while (I_GetTime() < stoptic)
I_StartTic();
I_StartTic();
while ((ev = D_PopEvent()) != NULL)
{
if (ev->type == ev_keydown && ev->data1 == KEY_ESCAPE)
I_Error("Network game synchronization aborted.");
}
}
/*
=====================
=
= D_ArbitrateNetStart
=
=====================
*/
void D_ArbitrateNetStart(void)
{
int i;
boolean gotinfo[MAXNETNODES];
autostart = true;
memset(gotinfo, 0, sizeof(gotinfo));
if (doomcom->consoleplayer)
{ // listen for setup info from key player
// mprintf ("listening for network start info...\n");
while (1)
{
CheckAbort();
if (!HGetPacket())
continue;
if (netbuffer->checksum & NCMD_SETUP)
{
if (netbuffer->player != HERETIC_VERSION)
I_Error
("Different DOOM versions cannot play a net game!");
startskill = netbuffer->retransmitfrom & 15;
deathmatch = (netbuffer->retransmitfrom & 0xc0) >> 6;
nomonsters = (netbuffer->retransmitfrom & 0x20) > 0;
respawnparm = (netbuffer->retransmitfrom & 0x10) > 0;
//startmap = netbuffer->starttic & 0x3f;
//startepisode = netbuffer->starttic >> 6;
startmap = netbuffer->starttic & 15;
startepisode = netbuffer->starttic >> 4;
return;
}
}
}
else
{ // key player, send the setup info
// mprintf ("sending network start info...\n");
do
{
CheckAbort();
for (i = 0; i < doomcom->numnodes; i++)
{
netbuffer->retransmitfrom = startskill;
if (deathmatch)
netbuffer->retransmitfrom |= (deathmatch << 6);
if (nomonsters)
netbuffer->retransmitfrom |= 0x20;
if (respawnparm)
netbuffer->retransmitfrom |= 0x10;
//netbuffer->starttic = startepisode * 64 + startmap;
netbuffer->starttic = (startepisode << 4) + startmap;
netbuffer->player = HERETIC_VERSION;
netbuffer->numtics = 0;
HSendPacket(i, NCMD_SETUP);
}
#if 1
for (i = 10; i && HGetPacket(); --i)
{
if ((netbuffer->player & 0x7f) < MAXNETNODES)
gotinfo[netbuffer->player & 0x7f] = true;
}
#else
while (HGetPacket())
{
gotinfo[netbuffer->player & 0x7f] = true;
}
#endif
for (i = 1; i < doomcom->numnodes; i++)
if (!gotinfo[i])
break;
}
while (i < doomcom->numnodes);
}
}
/*
====================
=
= I_InitNetwork
=
====================
*/
static void I_InitNetwork(void)
{
doomcom = malloc(sizeof(*doomcom));
memset(doomcom, 0, sizeof(*doomcom));
netgame = false;
doomcom->id = DOOMCOM_ID;
doomcom->numplayers = 1;
doomcom->numnodes = 1;
doomcom->deathmatch = false;
doomcom->consoleplayer = 0;
doomcom->ticdup = 1;
doomcom->extratics = 0;
}
/*
===================
=
= D_CheckNetGame
=
= Works out player numbers among the net participants
===================
*/
extern int viewangleoffset;
void D_CheckNetGame(void)
{
int i;
for (i = 0; i < MAXNETNODES; i++)
{
nodeingame[i] = false;
nettics[i] = 0;
remoteresend[i] = false; // set when local needs tics
resendto[i] = 0; // which tic to start sending
}
// I_InitNetwork sets doomcom and netgame
I_InitNetwork();
if (doomcom->id != DOOMCOM_ID)
I_Error("Doomcom buffer invalid!");
netbuffer = &doomcom->data;
consoleplayer = displayplayer = doomcom->consoleplayer;
if (netgame)
D_ArbitrateNetStart();
//printf ("startskill %i deathmatch: %i startmap: %i startepisode: %i\n", startskill, deathmatch, startmap, startepisode);
// read values out of doomcom
ticdup = doomcom->ticdup;
maxsend = BACKUPTICS / (2 * ticdup) - 1;
if (maxsend < 1)
maxsend = 1;
for (i = 0; i < doomcom->numplayers; i++)
playeringame[i] = true;
for (i = 0; i < doomcom->numnodes; i++)
nodeingame[i] = true;
//printf ("player %i of %i (%i nodes)\n", consoleplayer+1, doomcom->numplayers, doomcom->numnodes);
}
/*
==================
=
= D_QuitNetGame
=
= Called before quitting to leave a net game without hanging the
= other players
=
==================
*/
void D_QuitNetGame(void)
{
int i, j;
if (debugfile)
fclose(debugfile);
if (!netgame || !usergame || consoleplayer == -1 || demoplayback)
return;
// send a bunch of packets for security
netbuffer->player = consoleplayer;
netbuffer->numtics = 0;
for (i = 0; i < 4; i++)
{
for (j = 1; j < doomcom->numnodes; j++)
if (nodeingame[j])
HSendPacket(j, NCMD_EXIT);
I_WaitVBL(1);
}
}
/*
===============
=
= TryRunTics
=
===============
*/
int frametics[4], frameon;
int frameskip[4];
int oldnettics;
extern boolean advancedemo;
void TryRunTics(void)
{
int i;
int lowtic;
int entertic;
static int oldentertics;
int realtics, availabletics;
int counts;
int numplaying;
//
// get real tics
//
entertic = I_GetTime() / ticdup;
realtics = entertic - oldentertics;
oldentertics = entertic;
//
// get available tics
//
NetUpdate();
lowtic = INT_MAX;
numplaying = 0;
for (i = 0; i < doomcom->numnodes; i++)
if (nodeingame[i])
{
numplaying++;
if (nettics[i] < lowtic)
lowtic = nettics[i];
}
availabletics = lowtic - gametic / ticdup;
//
// decide how many tics to run
//
if (realtics < availabletics - 1)
counts = realtics + 1;
else if (realtics < availabletics)
counts = realtics;
else
counts = availabletics;
if (counts < 1)
counts = 1;
frameon++;
if (debugfile)
fprintf(debugfile, "=======real: %i avail: %i game: %i\n", realtics,
availabletics, counts);
if (!demoplayback)
{
//=============================================================================
//
// ideally nettics[0] should be 1 - 3 tics above lowtic
// if we are consistantly slower, speed up time
//
for (i = 0; i < MAXPLAYERS; i++)
if (playeringame[i])
break;
if (consoleplayer == i)
{ // the key player does not adapt
}
else
{
if (nettics[0] <= nettics[nodeforplayer[i]])
{
gametime--;
// printf ("-");
}
frameskip[frameon & 3] = (oldnettics > nettics[nodeforplayer[i]]);
oldnettics = nettics[0];
if (frameskip[0] && frameskip[1] && frameskip[2] && frameskip[3])
{
skiptics = 1;
// printf ("+");
}
}
//=============================================================================
} // demoplayback
//
// wait for new tics if needed
//
while (lowtic < gametic / ticdup + counts)
{
NetUpdate();
lowtic = INT_MAX;
for (i = 0; i < doomcom->numnodes; i++)
if (nodeingame[i] && nettics[i] < lowtic)
lowtic = nettics[i];
if (lowtic < gametic / ticdup)
I_Error("TryRunTics: lowtic < gametic");
// don't stay in here forever -- give the menu a chance to work
if (I_GetTime() / ticdup - entertic >= 20)
{
MN_Ticker();
return;
}
// Don't hog the CPU
I_Sleep(1);
}
//
// run the count * ticdup dics
//
while (counts--)
{
for (i = 0; i < ticdup; i++)
{
if (gametic / ticdup > lowtic)
I_Error("gametic>lowtic");
if (advancedemo)
D_DoAdvanceDemo();
MN_Ticker();
G_Ticker();
gametic++;
//
// modify command for duplicated tics
//
if (i != ticdup - 1)
{
ticcmd_t *cmd;
int buf;
int j;
buf = (gametic / ticdup) % BACKUPTICS;
for (j = 0; j < MAXPLAYERS; j++)
{
cmd = &netcmds[j][buf];
cmd->chatchar = 0;
if (cmd->buttons & BT_SPECIAL)
cmd->buttons = 0;
}
}
}
NetUpdate(); // check for new console commands
}
}