/*
* ===============
* CL_Netchan_Transmit
* ================
*/
void CL_Netchan_Transmit(netchan_t *chan, msg_t *msg)
{
MSG_WriteByte(msg, clc_EOF);
CL_Netchan_Encode(msg);
Netchan_Transmit(chan, msg->cursize, msg->data);
}
/*
* =================
* Netchan_SV_Process
* =================
*/
bool SV_Netchan_Process(client_t *client, msg_t *msg)
{
int ret;
ret = Netchan_Process(&client->netchan, msg);
if (!ret)
{
return(false);
}
SV_Netchan_Decode(client, msg);
return(true);
}
/*
* =================
* CL_Netchan_Process
* =================
*/
bool CL_Netchan_Process(netchan_t *chan, msg_t *msg)
{
int ret;
ret = Netchan_Process(chan, msg);
if (!ret)
{
return(false);
}
CL_Netchan_Decode(msg);
newsize += msg->cursize;
return(true);
}
/*
* ==================
* SV_UpdateServerCommandsToClient
*
* (re)send all server commands the client hasn't acknowledged yet
* ==================
*/
void SV_UpdateServerCommandsToClient(client_t *client, msg_t *msg)
{
int i;
// write any unacknowledged serverCommands
for (i = client->reliableAcknowledge + 1; i <= client->reliableSequence; i++)
{
MSG_WriteByte(msg, svc_serverCommand);
MSG_WriteLong(msg, i);
MSG_WriteString(msg, client->reliableCommands[i & (MAX_RELIABLE_COMMANDS - 1)]);
}
client->reliableSent = client->reliableSequence;
}
/*
* ==============
* CL_Netchan_Encode
*
* // first 12 bytes of the data are always:
* long serverId;
* long messageAcknowledge;
* long reliableAcknowledge;
*
* ==============
*/
static void CL_Netchan_Encode(msg_t *msg)
{
int serverId, messageAcknowledge, reliableAcknowledge;
int i, index, srdc, sbit, soob;
byte key, *string;
if (msg->cursize <= CL_ENCODE_START)
{
return;
}
srdc = msg->readcount;
sbit = msg->bit;
soob = msg->oob;
msg->bit = 0;
msg->readcount = 0;
msg->oob = (bool)0;
serverId = MSG_ReadLong(msg);
messageAcknowledge = MSG_ReadLong(msg);
reliableAcknowledge = MSG_ReadLong(msg);
msg->oob = (bool)soob;
msg->bit = sbit;
msg->readcount = srdc;
string = (byte *)clc.serverCommands[reliableAcknowledge & (MAX_RELIABLE_COMMANDS - 1)];
index = 0;
//
key = clc.challenge ^ serverId ^ messageAcknowledge;
for (i = CL_ENCODE_START; i < msg->cursize; i++)
{
// modify the key with the last received now acknowledged server command
if (!string[index])
{
index = 0;
}
if (string[index] > 127 || string[index] == '%')
{
key ^= '.' << (i & 1);
}
else
{
key ^= string[index] << (i & 1);
}
index++;
// encode the data with this key
*(msg->data + i) = (*(msg->data + i)) ^ key;
}
}
/*
* ==============
* SV_Netchan_Encode
*
* // first four bytes of the data are always:
* long reliableAcknowledge;
*
* ==============
*/
static void SV_Netchan_Encode(client_t *client, msg_t *msg)
{
long reliableAcknowledge, i, index;
byte key, *string;
int srdc, sbit, soob;
if (msg->cursize < SV_ENCODE_START)
{
return;
}
srdc = msg->readcount;
sbit = msg->bit;
soob = msg->oob;
msg->bit = 0;
msg->readcount = 0;
msg->oob = (bool)0;
reliableAcknowledge = MSG_ReadLong(msg);
msg->oob = (bool)soob;
msg->bit = sbit;
msg->readcount = srdc;
string = (byte *)client->lastClientCommandString;
index = 0;
// xor the client challenge with the netchan sequence number
key = client->challenge ^ client->netchan.outgoingSequence;
for (i = SV_ENCODE_START; i < msg->cursize; i++)
{
// modify the key with the last received and with this message acknowledged client command
if (!string[index])
{
index = 0;
}
if (string[index] > 127 || string[index] == '%')
{
key ^= '.' << (i & 1);
}
else
{
key ^= string[index] << (i & 1);
}
index++;
// encode the data with this key
*(msg->data + i) = *(msg->data + i) ^ key;
}
}
/*
* ==============
* SV_Netchan_Decode
*
* // first 12 bytes of the data are always:
* long serverId;
* long messageAcknowledge;
* long reliableAcknowledge;
*
* ==============
*/
static void SV_Netchan_Decode(client_t *client, msg_t *msg)
{
int serverId, messageAcknowledge, reliableAcknowledge;
int i, index, srdc, sbit, soob;
byte key, *string;
srdc = msg->readcount;
sbit = msg->bit;
soob = msg->oob;
msg->oob = (bool)0;
serverId = MSG_ReadLong(msg);
messageAcknowledge = MSG_ReadLong(msg);
reliableAcknowledge = MSG_ReadLong(msg);
msg->oob = (bool)soob;
msg->bit = sbit;
msg->readcount = srdc;
string = (byte *)client->reliableCommands[reliableAcknowledge & (MAX_RELIABLE_COMMANDS - 1)];
index = 0;
//
key = client->challenge ^ serverId ^ messageAcknowledge;
for (i = msg->readcount + SV_DECODE_START; i < msg->cursize; i++)
{
// modify the key with the last sent and acknowledged server command
if (!string[index])
{
index = 0;
}
if (string[index] > 127 || string[index] == '%')
{
key ^= '.' << (i & 1);
}
else
{
key ^= string[index] << (i & 1);
}
index++;
// decode the data with this key
*(msg->data + i) = *(msg->data + i) ^ key;
}
}
/*
* ==============
* CL_Netchan_Decode
*
* // first four bytes of the data are always:
* long reliableAcknowledge;
*
* ==============
*/
static void CL_Netchan_Decode(msg_t *msg)
{
long reliableAcknowledge, i, index;
byte key, *string;
int srdc, sbit, soob;
srdc = msg->readcount;
sbit = msg->bit;
soob = msg->oob;
msg->oob = (bool)0;
reliableAcknowledge = MSG_ReadLong(msg);
msg->oob = (bool)soob;
msg->bit = sbit;
msg->readcount = srdc;
string = (byte *)clc.reliableCommands[reliableAcknowledge & (MAX_RELIABLE_COMMANDS - 1)];
index = 0;
// xor the client challenge with the netchan sequence number (need something that changes every message)
key = clc.challenge ^ LittleLong(*(unsigned *)msg->data);
for (i = msg->readcount + CL_DECODE_START; i < msg->cursize; i++)
{
// modify the key with the last sent and with this message acknowledged client command
if (!string[index])
{
index = 0;
}
if (string[index] > 127 || string[index] == '%')
{
key ^= '.' << (i & 1);
}
else
{
key ^= string[index] << (i & 1);
}
index++;
// decode the data with this key
*(msg->data + i) = *(msg->data + i) ^ key;
}
}
/*
* ===============
* SV_Netchan_Transmit
* TTimo
* https://zerowing.idsoftware.com/bugzilla/show_bug.cgi?id=462
* if there are some unsent fragments (which may happen if the snapshots
* and the gamestate are fragmenting, and collide on send for instance)
* then buffer them and make sure they get sent in correct order
* ================
*/
void SV_Netchan_Transmit(client_t *client, msg_t *msg) //int length, const byte *data ) {
{
MSG_WriteByte(msg, svc_EOF);
if (client->netchan.unsentFragments)
{
netchan_buffer_t *netbuf;
Com_DPrintf("#462 SV_Netchan_Transmit: unsent fragments, stacked\n");
netbuf = (netchan_buffer_t *)Z_Malloc(sizeof(netchan_buffer_t));
// store the msg, we can't store it encoded, as the encoding depends on stuff we still have to finish sending
MSG_Copy(&netbuf->msg, netbuf->msgBuffer, sizeof(netbuf->msgBuffer), msg);
netbuf->next = NULL;
// insert it in the queue, the message will be encoded and sent later
*client->netchan_end_queue = netbuf;
client->netchan_end_queue = &(*client->netchan_end_queue)->next;
// emit the next fragment of the current message for now
Netchan_TransmitNextFragment(&client->netchan);
}
else
{
SV_Netchan_Encode(client, msg);
Netchan_Transmit(&client->netchan, msg->cursize, msg->data);
}
}
void Huff_Decompress(msg_t *mbuf, int offset)
{
int ch, cch, i, j, size;
byte seq[65536];
bool Sys_GetPacket(netadr_t *net_from, msg_t *net_message);
/*
* =============================================================================
*
* Delta encode a client frame onto the network channel
*
* A normal server packet will look like:
*
* 4 sequence number (high bit set if an oversize fragment)
* <optional reliable commands>
* 1 svc_snapshot
* 4 last client reliable command
* 4 serverTime
* 1 lastframe for delta compression
* 1 snapFlags
* 1 areaBytes
* <areabytes>
* <playerstate>
* <packetentities>
*
* =============================================================================
*/
/*
* =============
* SV_EmitPacketEntities
*
* Writes a delta update of an entityState_t list to the message.
* =============
*/
static void SV_EmitPacketEntities(clientSnapshot_t *from, clientSnapshot_t *to, msg_t *msg)
{
entityState_t *oldent, *newent;
int oldindex, newindex;
int oldnum, newnum;
int from_num_entities;
// generate the delta update
if (!from)
{
from_num_entities = 0;
}
else
{
from_num_entities = from->num_entities;
}
newent = NULL;
oldent = NULL;
newindex = 0;
oldindex = 0;
while (newindex < to->num_entities || oldindex < from_num_entities)
{
if (newindex >= to->num_entities)
{
newnum = 9999;
}
else
{
newent = &svs.snapshotEntities[(to->first_entity + newindex) % svs.numSnapshotEntities];
newnum = newent->number;
}
if (oldindex >= from_num_entities)
{
oldnum = 9999;
}
else
{
oldent = &svs.snapshotEntities[(from->first_entity + oldindex) % svs.numSnapshotEntities];
oldnum = oldent->number;
}
if (newnum == oldnum)
{
// delta update from old position
// because the force parm is false, this will not result
// in any bytes being emited if the entity has not changed at all
MSG_WriteDeltaEntity(msg, oldent, newent, false);
oldindex++;
newindex++;
continue;
}
if (newnum < oldnum)
{
// this is a new entity, send it from the baseline
MSG_WriteDeltaEntity(msg, &sv.svEntities[newnum].baseline, newent, true);
newindex++;
continue;
}
if (newnum > oldnum)
{
// the old entity isn't present in the new message
MSG_WriteDeltaEntity(msg, oldent, NULL, true);
oldindex++;
continue;
}
}
MSG_WriteBits(msg, (MAX_GENTITIES - 1), GENTITYNUM_BITS); // end of packetentities
}
/*
* ==================
* SV_WriteSnapshotToClient
* ==================
*/
static void SV_WriteSnapshotToClient(client_t *client, msg_t *msg)
{
clientSnapshot_t *frame, *oldframe;
int lastframe;
int i;
int snapFlags;
// this is the snapshot we are creating
frame = &client->frames[client->netchan.outgoingSequence & PACKET_MASK];
// try to use a previous frame as the source for delta compressing the snapshot
if (client->deltaMessage <= 0 || client->state != CS_ACTIVE)
{
// client is asking for a retransmit
oldframe = NULL;
lastframe = 0;
}
else if (client->netchan.outgoingSequence - client->deltaMessage
>= (PACKET_BACKUP - 3))
{
// client hasn't gotten a good message through in a long time
Com_DPrintf("%s: Delta request from out of date packet.\n", client->name);
oldframe = NULL;
lastframe = 0;
}
else
{
// we have a valid snapshot to delta from
oldframe = &client->frames[client->deltaMessage & PACKET_MASK];
lastframe = client->netchan.outgoingSequence - client->deltaMessage;
// the snapshot's entities may still have rolled off the buffer, though
if (oldframe->first_entity <= svs.nextSnapshotEntities - svs.numSnapshotEntities)
{
Com_DPrintf("%s: Delta request from out of date entities.\n", client->name);
oldframe = NULL;
lastframe = 0;
}
}
MSG_WriteByte(msg, svc_snapshot);
// NOTE, MRE: now sent at the start of every message from server to client
// let the client know which reliable clientCommands we have received
//MSG_WriteLong( msg, client->lastClientCommand );
// send over the current server time so the client can drift
// its view of time to try to match
MSG_WriteLong(msg, svs.time);
// what we are delta'ing from
MSG_WriteByte(msg, lastframe);
snapFlags = svs.snapFlagServerBit;
if (client->rateDelayed)
{
snapFlags |= SNAPFLAG_RATE_DELAYED;
}
if (client->state != CS_ACTIVE)
{
snapFlags |= SNAPFLAG_NOT_ACTIVE;
}
MSG_WriteByte(msg, snapFlags);
// send over the areabits
MSG_WriteByte(msg, frame->areabytes);
MSG_WriteData(msg, frame->areabits, frame->areabytes);
// delta encode the playerstate
if (oldframe)
{
MSG_WriteDeltaPlayerstate(msg, &oldframe->ps, &frame->ps);
}
else
{
MSG_WriteDeltaPlayerstate(msg, NULL, &frame->ps);
}
// delta encode the entities
SV_EmitPacketEntities(oldframe, frame, msg);
// padding for rate debugging
if (sv_padPackets->integer)
{
for (i = 0; i < sv_padPackets->integer; i++)
{
MSG_WriteByte(msg, svc_nop);
}
}
}
