////////////////////////////////////////////////////
// setCache
// adds current packet to specified cache
void EQPacketStream::setCache(uint16_t serverArqSeq, EQProtocolPacket& packet)
{
// check if the entry already exists in the cache
EQPacketMap::iterator it = m_cache.find(serverArqSeq);
if (it == m_cache.end())
{
// entry doesn't exist, so insert an entry into the cache
#ifdef PACKET_PROCESS_DIAG
seqDebug("SEQ: Insert arq (%04x) stream %d into cache", serverArqSeq, m_streamid);
#endif
m_cache.insert(EQPacketMap::value_type(serverArqSeq,
new EQProtocolPacket(packet, true)));
emit cacheSize(m_cache.size(), (int)m_streamid);
}
else
{
// replacing an existing entry, make sure the new data is valid
#ifdef APPLY_CRC_CHECK
if (! packet.hasCRC() || calculateCRC(packet) == packet.crc())
#endif
{
#ifdef PACKET_PROCESS_DIAG
seqDebug("SEQ: Update arq (%04x) stream %d in cache", serverArqSeq, m_streamid);
#endif
// Free the old packet at this place and replace with the new one.
delete it->second;
it->second = new EQProtocolPacket(packet, true);
}
#if defined(PACKET_PROCESS_DIAG) && defined(APPLY_CRC_CHECK)
else
seqDebug("SEQ: Not Updating arq (%04x) stream %d into cache, CRC error!",
serverArqSeq, m_streamid);
#endif
}
#ifdef PACKET_CACHE_DIAG
if (m_cache.size() > m_maxCacheCount)
m_maxCacheCount = m_cache.size();
#endif // PACKET_CACHE_DIAG
}
////////////////////////////////////////////////////
// Cache processing
void EQPacketStream::processCache()
{
#if defined(PACKET_CACHE_DIAG)
seqDebug("SEQ: START checking stream %s cache, arq %04x, cache count %04d",
EQStreamStr[m_streamid], m_arqSeqExp, m_cache.size());
#endif
EQPacketMap::iterator it;
EQPacketMap::iterator eraseIt;
EQProtocolPacket* packet;
// check if the cache has grown large enough that we should give up
// on seeing the current serverArqSeqExp
//
// If people see this a lot, they either have pathetic network cards, or
// are having problems keeping up with packets (slow computer? Too much
// net traffic?). Some possible solutions to this are to turn on session
// tracking to filter out more PF_PACKET packets from getting passed out of
// the kernel and to up the socket receive buffer sizes. See FAQ for
// more information.
if (m_cache.size() >= m_arqSeqGiveUp)
{
// ok, if the expected server arq sequence isn't here yet, give up
// attempt to find the current expencted arq seq
it = m_cache.find(m_arqSeqExp);
// keep trying to find a new serverArqSeqExp if we haven't found a good
// one yet...
while(it == m_cache.end())
{
seqWarn("SEQ: Giving up on finding arq %04x in stream %s cache, skipping!",
m_arqSeqExp, EQStreamStr[m_streamid]);
// incremente the expected arq sequence number
m_arqSeqExp++;
emit seqExpect(m_arqSeqExp, (int)m_streamid);
// attempt to find the new current expencted arq seq
it = m_cache.find(m_arqSeqExp);
}
}
else
{
// haven't given up yet, just try to find the current serverArqSeqExp
// attempt to find the current expected ARQ seq
it = m_cache.find(m_arqSeqExp);
}
// iterate over cache until we reach the end or run out of
// immediate followers
while (it != m_cache.end())
{
// get the PacketFormat for the iterator
packet = it->second;
// make sure this is the expected packet
// (we might have incremented to the one after the one returned
// by find above).
if (packet->arqSeq() != m_arqSeqExp)
break;
#ifdef PACKET_CACHE_DIAG
seqDebug("SEQ: found next arq %04x in stream %s cache, cache count %04d",
m_arqSeqExp, EQStreamStr[m_streamid], m_cache.size());
#endif
// validate the packet with a crc check. If the packet is for an old
// session, we probably shouldn't be using it!
#ifdef APPLY_CRC_CHECK
if (packet->hasCRC() && packet->crc() != calculateCRC(*packet))
{
#if defined (PACKET_CACHE_DIAG)
// Something's screwed up
seqDebug("SEQ: INVALID PACKET: Bad CRC in packet in stream %s cache with arq %04x! Droping it, but leaving expected seq as %04x",
EQStreamStr[m_streamid], packet->arqSeq(), m_arqSeqExp);
#endif
// Need to drop from the cache
eraseIt = it;
// increment the current position iterator
it++;
// erase the packet from the cache
m_cache.erase(eraseIt);
emit cacheSize(m_cache.size(), (int)m_streamid);
#ifdef PACKET_CACHE_DIAG
seqDebug("SEQ: REMOVING arq %04x from stream %s cache, cache count %04d",
packet->arqSeq(), EQStreamStr[m_streamid], m_cache.size());
#endif
// delete the packet
delete packet;
// No sense looping some more.
break;
}
else
#endif /* APPLY_CRC_CHECK */
{
#if defined (PACKET_CACHE_DIAG) && (PACKET_CACHE_DIAG > 2)
seqDebug("SEQ: Found next arq in stream %s cache, incrementing arq seq, %04x",
EQStreamStr[m_streamid], packet->arqSeq());
#endif
// Process the packet since it's next in the sequence and was just
// received out of order
processPacket(*packet, packet->isSubpacket());
// Need to drop from the cache
eraseIt = it;
// increment the current position iterator
it++;
// erase the packet from the cache
m_cache.erase(eraseIt);
emit cacheSize(m_cache.size(), (int)m_streamid);
#ifdef PACKET_CACHE_DIAG
seqDebug("SEQ: REMOVING arq %04x from stream %s cache, cache count %04d",
packet->arqSeq(), EQStreamStr[m_streamid], m_cache.size());
#endif
// delete the packet
delete packet;
if (m_arqSeqExp == 0)
it = m_cache.begin();
}
}
#ifdef PACKET_CACHE_DIAG
seqDebug("SEQ: FINISHED checking stream %s cache, arq %04x, cache count %04d",
EQStreamStr[m_streamid], m_arqSeqExp, m_cache.size());
#endif
}
