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2017.2 Multiplayer compatibility fixes

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2017.2 in compatible mode was not compatible with 2017.1.x because the V1 packet had V2 properties in it; the protocol version and the new launchbar encoding - both of which should not be transmitted. This only affected 2017.1 because it discards the rest of the packet once an unknown property is encountered (to increase reliability).
This commit is contained in:
Richard Harrison 2017-05-20 13:31:46 +02:00
parent ef66ba69c1
commit ee951c00e7
1 changed files with 30 additions and 8 deletions
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38
src/MultiPlayer/multiplaymgr.cxx
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@ -89,9 +89,12 @@ enum TransmissionType {
* The pad magic is used to force older clients to use verifyProperties and as the first property transmitted is short int encoded it
* will cause the rest of the packet to be discarded. This is the section of the packet that contains the properties defined in the list
* here - the basic motion properties remain compatible, so the older client will see just the model, not chat, not animations etc.
* The lower 16 bits of the prop_id (version) are the version and the upper 16bits are for meta data.
*/
const int V1_1_PROP_ID = 1;
const int V1_1_2_PROP_ID = 2;
const int V2_PROP_ID_PROTOCOL = 0x10001;
const int V2_PAD_MAGIC = 0x1face002;
/*
@ -200,7 +203,7 @@ static xdr_data_t *decode_received_launchbar_state(const IdPropertyList *propDef
// This should be extendable dynamically for every specific aircraft ...
// For now only that static list
static const IdPropertyList sIdPropertyList[] = {
{ 10, "sim/multiplay/protocol-version", simgear::props::INT, TT_SHORTINT, V1_1_PROP_ID, NULL, NULL },
{ 10, "sim/multiplay/protocol-version", simgear::props::INT, TT_SHORTINT, V2_PROP_ID_PROTOCOL, NULL, NULL },
{ 100, "surface-positions/left-aileron-pos-norm", simgear::props::FLOAT, TT_SHORT_FLOAT_NORM, V1_1_PROP_ID, NULL, NULL },
{ 101, "surface-positions/right-aileron-pos-norm", simgear::props::FLOAT, TT_SHORT_FLOAT_NORM, V1_1_PROP_ID, NULL, NULL },
{ 102, "surface-positions/elevator-pos-norm", simgear::props::FLOAT, TT_SHORT_FLOAT_NORM, V1_1_PROP_ID, NULL, NULL },
@ -1102,6 +1105,8 @@ FGMultiplayMgr::isSane(const FGExternalMotionData& motionInfo)
void
FGMultiplayMgr::SendMyPosition(const FGExternalMotionData& motionInfo)
{
int protocolToUse = getProtocolToUse();
if ((! mInitialised) || (! mHaveServer))
return;
@ -1130,7 +1135,7 @@ FGMultiplayMgr::SendMyPosition(const FGExternalMotionData& motionInfo)
* MP2017(V2) (for V1 clients) will always have an unknown property because V2 transmits
* the protocol version as the very first property as a shortint.
*/
if (getProtocolToUse() > 1)
if (protocolToUse > 1)
PosMsg->pad = XDR_encode_int32(V2_PAD_MAGIC);
else
PosMsg->pad = 0;
@ -1189,19 +1194,34 @@ FGMultiplayMgr::SendMyPosition(const FGExternalMotionData& motionInfo)
xdr_data_t* data = ptr;
xdr_data_t* msgEnd = msgBuf.propsEnd();
int protocolVersion = getProtocolToUse();
//if (pMultiPlayDebugLevel->getIntValue())
// msgBuf.zero();
struct BoolArrayBuffer boolBuffer[MAX_BOOL_BUFFERS];
memset(&boolBuffer, 0, sizeof(boolBuffer));
for (int partition = 1; partition <= protocolVersion; partition++)
for (int partition = 1; partition <= protocolToUse; partition++)
{
std::vector<FGPropertyData*>::const_iterator it = motionInfo.properties.begin();
while (it != motionInfo.properties.end()) {
const struct IdPropertyList* propDef = mPropertyDefinition[(*it)->id];
if (propDef->version == partition || propDef->version > getProtocolToUse())
/*
* Excludes the 2017.2 property for the protocol version from V1 packets.
*/
if (protocolToUse == 1 && propDef->version == V2_PROP_ID_PROTOCOL)
{
++it;
continue;
}
/*
* 2017.2 partitions the buffer sent into protocol versions. Originally this was intended to allow
* compatability with older clients; however this will only work in the future or with support from fgms
* - so if a future version adds more properties to the protocol these can be transmitted in a third partition
* that will be ignored by older clients (such as 2017.2).
*/
if ( (propDef->version & 0xffff) == partition || (propDef->version & 0xffff) > protocolToUse)
{
if (ptr + 2 >= msgEnd)
{
@ -1220,7 +1240,7 @@ FGMultiplayMgr::SendMyPosition(const FGExternalMotionData& motionInfo)
*/
int transmit_type = (*it)->type;
if (propDef->TransmitAs != TT_ASIS && protocolVersion > 1)
if (propDef->TransmitAs != TT_ASIS && protocolToUse > 1)
{
transmit_type = propDef->TransmitAs;
}
@ -1233,7 +1253,7 @@ FGMultiplayMgr::SendMyPosition(const FGExternalMotionData& motionInfo)
": buf[" << (ptr - data) * sizeof(*ptr)
<< "] id=" << (*it)->id << " type " << transmit_type);
if (propDef->encode_for_transmit)
if (propDef->encode_for_transmit && protocolToUse > 1)
{
ptr = (*propDef->encode_for_transmit)(propDef, ptr, (*it));
}
@ -1241,6 +1261,8 @@ FGMultiplayMgr::SendMyPosition(const FGExternalMotionData& motionInfo)
{
// The actual data representation depends on the type
switch (transmit_type) {
case TT_NOSEND:
break;
case TT_SHORTINT:
{
*ptr++ = XDR_encode_shortints32((*it)->id, (*it)->int_value);
@ -1310,7 +1332,7 @@ FGMultiplayMgr::SendMyPosition(const FGExternalMotionData& motionInfo)
case simgear::props::STRING:
case simgear::props::UNSPECIFIED:
{
if (protocolVersion > 1)
if (protocolToUse > 1)
{
// New string encoding:
// xdr[0] : ID length packed into 32 bit containing two shorts.