void RfidReaderMac::handlePacketSent(PacketPtr packet)
{
if(isPacketType(packet, RfidReaderMacData::Types_Request)) {
// Start a cycle
m_currentSlotNumber = 0;
RfidReaderMacDataPtr macData =
boost::dynamic_pointer_cast<RfidReaderMacData>
(packet->getData(Packet::DataTypes_Link));
assert(macData.get() != 0);
m_numberOfSlots = macData->getNumberOfSlots();
} else if(isPacketType(packet, RfidReaderMacData::Types_Select)) {
m_doResetSlot = true;
// m_currentSlotNumber is already set to slot i+1, so
// the resetSlotNumber should be slot i+2. Thus, we
// add one to currentSlotNumber.
m_resetSlotNumber = m_currentSlotNumber + 1;
/*
cout << "slot: " << m_currentSlotNumber << " resetSlot: " <<
m_resetSlotNumber << endl;
*/
} else if(isPacketType(packet, RfidReaderMacData::Types_Ack)) {
if(isEnoughTimeForContentionCycle()) {
startNextContentionCycle();
}
} else {
unblockUpperQueues();
}
}
bool SimulatorLink::sendData(PacketPtr data) {
// Create a copy, or we get the really wierd situation where updating the number of
// hops on one router will change all copies of the packet, even those in transit!
PacketPtr ptr = std::make_shared<Packet>(data->getData(), data->getDataLength());
sendQueue.push(ptr);
return true;
}
bool RfidReaderMac::isPacketType(PacketPtr packet,
RfidReaderMacData::Types type) const
{
bool isType = false;
RfidReaderMacDataPtr macData =
boost::dynamic_pointer_cast<RfidReaderMacData>
(packet->getData(Packet::DataTypes_Link));
if(macData.get() != 0 && macData->getType() == type) {
isType = true;
}
return isType;
}
bool RfidReaderMac::handleRecvdUpperLayerPacket(PacketPtr packet,
t_uint sendingLayerIdx)
{
RfidReaderAppDataPtr appData =
boost::dynamic_pointer_cast<RfidReaderAppData>
(packet->getData(Packet::DataTypes_Application));
bool wasSuccessful = false;
if(m_DEBUG) {
ostringstream debugStream;
debugStream << __PRETTY_FUNCTION__;
LogStreamManager::instance()->logDebugItem(
debugStream.str());
}
// For now, we only handle application packets.
if(appData.get() != 0) {
switch(appData->getType()) {
case RfidReaderAppData::Types_Read:
// We'll only handle one packet at a time
blockUpperQueues();
assert(m_currentAppReadPacket.get() == 0);
m_currentAppReadPacket = packet;
m_doEntireReadCycle = appData->getDoEntireReadCycle();
// Start cycle timer
assert(m_cycleTimer.get() != 0);
m_cycleTimer->start(m_nextCycleTime);
if(isEnoughTimeForContentionCycle()) {
startNextContentionCycle();
}
wasSuccessful = true;
break;
case RfidReaderAppData::Types_Reset:
// We'll only handle one packet at a time
blockUpperQueues();
assert(m_packetToTransmit == 0);
addGenericHeader(packet, NodeId::broadcastDestination());
m_packetToTransmit = packet;
m_txSlotNumber = m_currentSlotNumber;
wasSuccessful = true;
break;
default:
wasSuccessful = false;
}
assert(m_slotTimer.get() != 0 && m_slotTimer->isRunning());
}
return wasSuccessful;
}
bool RfidReaderMac::handleRecvdMacPacket(PacketPtr packet,
t_uint sendingLayerIdx)
{
RfidTagMacDataPtr macData =
boost::dynamic_pointer_cast<RfidTagMacData>
(packet->getData(Packet::DataTypes_Link));
bool wasSuccessful = true;
// For now, we'll only handle MAC packets from tags.
if(macData.get() != 0) {
if(packetIsForMe(macData)) {
switch(macData->getType()) {
case RfidTagMacData::Types_Reply:
// If we ended the cycle early due to too many
// consecutive missed reads, then the timer will
// be stopped and we shouldn't handle anymore
// REPLY packets.
if(m_cycleTimer->isRunning()) {
// It could be the case that this reply is received
// in a contention cycle after the a SELECT packet
// was lost. In response to the SELECT packet being
// lost in slot i, the reader will reset in
// slot i+2 and send a REQUEST in slot i+3.
// If this reply is received in slot i+2, we should
// ignore it since m_packetToTransmit already
// has a REQUEST packet pending.
if(m_packetToTransmit.get() == 0) {
assert(m_currentAppReadPacket.get() != 0);
// Send SELECT message header on the original
// app packet.
addSelectHeader(m_currentAppReadPacket,
macData->getSenderId());
m_packetToTransmit = m_currentAppReadPacket;
m_txSlotNumber = m_currentSlotNumber;
assert(m_slotTimer.get() != 0 &&
m_slotTimer->isRunning());
}
}
break;
case RfidTagMacData::Types_Generic:
// Subtract three from the winning slot number for:
// 1. The current slot number was incremented
// at the beginning of the slot.
// 2. The REPLY was sent two slots prior
// to this packet being received (the SELECT
// packet was sent one slot prior).
m_winningSlotNumbers.push_back(
make_pair(macData->getSenderId(),
(m_currentSlotNumber - 3)));
// Just pass the packet to upper layers.
wasSuccessful = sendToLinkLayer(
CommunicationLayer::Directions_Upper, packet);
m_packetToTransmit = createAckPacket(macData->getSenderId());
m_txSlotNumber = m_currentSlotNumber;
assert(m_slotTimer.get() != 0 &&
m_slotTimer->isRunning());
break;
default:
wasSuccessful = false;
}
}
}
return wasSuccessful;
}