private void InterceptFlowFrame(Flow flow)
{
if (!State.CanReceiveFrames())
throw new AmqpException(ErrorCode.IllegalState, $"Received Flow frame but session state is {State.ToString()}.");
if (State == SessionStateEnum.DISCARDING)
return;
nextIncomingId = flow.NextOutgoingId; // their next id
remoteOutgoingWindow = flow.OutgoingWindow; // their advertised outgoing window
// recalculate the remote session's advertised incoming-window based on the difference
// between the advertized next-incoming-id and our actual next-outgoing-id
// our outgoing-window is synchronized with the remote-incoming-window
if (flow.NextIncomingId.HasValue)
outgoingWindow = remoteIncomingWindow = flow.IncomingWindow + flow.NextIncomingId.Value - (uint)nextOutgoingId;
else
outgoingWindow = remoteIncomingWindow = flow.IncomingWindow + InitialOutgoingId - (uint)nextOutgoingId;
if (outgoingWindow > 0)
{
// TODO: flush queued outgoing transfers
}
if (flow.Handle != null)
{
var link = GetRemoteLink(flow.Handle.Value);
if (link.State == LinkStateEnum.DESTROYED)
throw new AmqpException(ErrorCode.ErrantLink, "If any input (other than a detach) related to the endpoint either via the input handle or delivery-ids be received, the session MUST be terminated with an errant-link session-error.");
link.HandleLinkFrame(flow);
}
else if (flow.Echo)
{
SendFlow(new Flow()
{
Echo = false,
});
}
}
private void HandleFlowFrame(Flow flow)
{
if (State != LinkStateEnum.ATTACHED && State != LinkStateEnum.DETACH_SENT && State != LinkStateEnum.DESTROYED)
throw new AmqpException(ErrorCode.IllegalState, $"Received Flow frame but link state is {State.ToString()}.");
if (State == LinkStateEnum.DESTROYED)
throw new AmqpException(ErrorCode.ErrantLink, $"Received Flow frame but link state is {State.ToString()}."); // TODO end session
if (State == LinkStateEnum.DETACH_SENT)
return; // ignore
if (IsReceiverLink)
{
// flow control from sender
if (flow.DeliveryCount.HasValue)
DeliveryCount = flow.DeliveryCount.Value;
// TODO: ignoring Available field for now
//if (flow.Available.HasValue)
// available = flow.Available.Value;
// TODO: respond to new flow control
}
if (IsSenderLink)
{
// flow control from receiver
if (flow.LinkCredit.HasValue)
LinkCredit = flow.LinkCredit.Value;
drainFlag = flow.Drain ?? false;
// TODO respond to new flow control
var receivedFlowCallback = this.ReceivedFlow;
if (receivedFlowCallback != null)
receivedFlowCallback(this, EventArgs.Empty);
}
if (flow.Echo)
{
SendFlow(drain: false, echo: false);
}
}
public void SendFlow(Flow flow)
{
incomingWindow = DefaultWindowSize; // reset window
flow.NextIncomingId = nextIncomingId;
flow.NextOutgoingId = nextOutgoingId;
flow.IncomingWindow = incomingWindow;
flow.OutgoingWindow = outgoingWindow;
SendFrame(flow);
}
