public void RemoveFragmentationMessage(FragmentationMessage fragmentationMessage)
{
lock (this)
{
_fragmentationMessagesArray.Remove(fragmentationMessage);
}
}
internal uint RegisterItem(long timeoutTick, FragmentationMessage message)
{
lock (_lock)
{
TimerItem item = new TimerItem(timeoutTick, message);
AddItemToList(item);
return item.Id;
}
}
internal uint RegisterItem(long timeoutTick, FragmentationMessage message)
{
lock (_lock)
{
TimerItem item = new TimerItem(timeoutTick, message);
AddItemToList(item);
return(item.Id);
}
}
/// <summary>
/// Remove all associations and dispose all fragmentation messages.
/// </summary>
public void Dispose()
{
lock (this)
{
int fragmentMessageArrayCount = _fragmentationMessagesArray.Count;
for (int i = 0; i < fragmentMessageArrayCount; i++)
{
FragmentationMessage msg = (FragmentationMessage)_fragmentationMessagesArray[i];
msg.Dispose();
}
_fragmentationMessagesArray.Clear();
}
}
internal void UnregisterItem(FragmentationMessage message)
{
lock (_lock)
{
for (int i = 0; i < _timerItems.Count; i++)
{
TimerItem item = (TimerItem)_timerItems[i];
if (item.Message == message)
{
RemoveItemFromList(i);
return;
}
}
}
}
/// <summary>
/// Get the active message associated to a remote node.
/// </summary>
/// <param name="node"></param>
/// <returns></returns>
public FragmentationMessage GetFragmentationMessage(UInt16 source, UInt16 destination)
{
lock (this)
{
int fragmentMessageArrayCount = _fragmentationMessagesArray.Count;
for (int i = 0; i < fragmentMessageArrayCount; i++)
{
FragmentationMessage msg = (FragmentationMessage)_fragmentationMessagesArray[i];
if ((msg.Source == source) && (msg.Destination == destination))
{
return(msg);
}
}
return(null);
}
}
/// <summary>
/// Set the fragmentation message associated to a pair of transmitting nodes.
/// </summary>
internal void SetFragmentationMessage(UInt16 source, UInt16 destination, FragmentationMessage fragmentationMessage)
{
if ((source != fragmentationMessage.Source) || (destination != fragmentationMessage.Destination))
{
throw new ArgumentException("Inconsistent parameters.");
}
lock (this)
{
// first. check whether there is already an active message associated to this node.
FragmentationMessage prevFragmentationMessage = GetFragmentationMessage(source, destination);
if (prevFragmentationMessage != null)
{
// there is already one active message associated with the node.
// remove this message first.
_fragmentationMessagesArray.Remove(prevFragmentationMessage);
}
_fragmentationMessagesArray.Add(fragmentationMessage);
return;
}
}
/// <summary>
/// Set the fragmentation message associated to a pair of transmitting nodes.
/// </summary>
internal void SetFragmentationMessage(UInt16 source, UInt16 destination, FragmentationMessage fragmentationMessage)
{
if ((source != fragmentationMessage.Source) || (destination != fragmentationMessage.Destination))
{
throw new ArgumentException("Inconsistent parameters.");
}
lock (this)
{
// first. check whether there is already an active message associated to this node.
FragmentationMessage prevFragmentationMessage = GetFragmentationMessage(source, destination);
if (prevFragmentationMessage != null)
{
// there is already one active message associated with the node.
// remove this message first.
_fragmentationMessagesArray.Remove(prevFragmentationMessage);
}
_fragmentationMessagesArray.Add(fragmentationMessage);
return;
}
}
public void RemoveFragmentationMessage(FragmentationMessage fragmentationMessage)
{
lock (this)
{
_fragmentationMessagesArray.Remove(fragmentationMessage);
}
}
internal TimerItem(long timeoutTicks, FragmentationMessage message)
{
Id = GetNextId();
TimeoutTicks = timeoutTicks;
Message = message;
}
internal TimeoutEventArgs(FragmentationMessage message)
{
_message = message;
}
internal void UnregisterItem(FragmentationMessage message)
{
lock (_lock)
{
for (int i = 0; i < _timerItems.Count; i++)
{
TimerItem item = (TimerItem)_timerItems[i];
if (item.Message == message)
{
RemoveItemFromList(i);
return;
}
}
}
}
public void HandleLowerLayerDataIndication(object sender, ushort originatorShortAddr, ushort targetShortAddr, Frame sdu)
{
FragmentationMessage fragMsg = null;
FragmentHeader header;
lock (_lock)
{
if ((!_started) || (sdu.LengthDataUsed < 2))
{
Frame.Release(ref sdu);
return;
}
// extract fragment header.
header = FragmentHeader.Decode(sdu.ReadUInt16(0));
sdu.DeleteFromFront(2);
FragmentationMessageAssociationSet associations;
switch (header.Type)
{
case FragmentType.DATA:
associations = _inboundAssociations;
if (associations == null)
{
Frame.Release(ref sdu);
return;
}
fragMsg = (InboundFragmentationMessage)associations.GetFragmentationMessage(originatorShortAddr, targetShortAddr);
if (fragMsg != null)
{
// there is already one message with this peer. Check freshness.
if (fragMsg.MessageNumber != header.MessageSeqNumber)
{
int sqnOld = (int)fragMsg.MessageNumber;
int sqnNew = (int)header.MessageSeqNumber;
int diff = (sqnNew > sqnOld) ? sqnNew - sqnOld : sqnNew - sqnOld + 256;
if ((header.MessageSeqNumber == 0) || (diff < 128))
{
// data received is most recent.
fragMsg.Dispose();
fragMsg = null;
}
else
{
// data received is old stuff.
Frame.Release(ref sdu);
return;
}
}
}
if (fragMsg == null)
{
// new message must be started
fragMsg = new InboundFragmentationMessage(originatorShortAddr, targetShortAddr,
header.MessageSeqNumber, _lowerLayerDataRequest, _lowerMtu, _lowerHead, _lowerTail, _timer);
fragMsg.FragmentationMessageTerminated += this.HandleFragmentationMessageTerminated;
associations.SetFragmentationMessage(originatorShortAddr, targetShortAddr, fragMsg);
}
break;
case FragmentType.ACK:
associations = _outboundAssociations;
if (associations == null)
{
Frame.Release(ref sdu);
return;
}
fragMsg = (OutboundFragmentationMessage)associations.GetFragmentationMessage(targetShortAddr, originatorShortAddr);
if ((fragMsg == null) || (fragMsg.MessageNumber != header.MessageSeqNumber))
{
//no one waiting for this segment. Discard.
#if DEBUG
Trace.Print("No one waiting for this segment. Discard.");
#endif
Frame.Release(ref sdu);
return;
}
break;
default:
break;
}
}
// release the lock before calling method in FragmentMessage class
if (fragMsg != null)
{
fragMsg.HandleReceivedFragment(header, ref sdu);
}
}
internal TimerItem(long timeoutTicks, FragmentationMessage message)
{
Id = GetNextId();
TimeoutTicks = timeoutTicks;
Message = message;
}
internal TimeoutEventArgs(FragmentationMessage message)
{
_message = message;
}