I have written a small embedded TCP/IP server application but it needs to work lock-step: one query then one response.
My problem is that the client (not under my control) making the requests is running ahead and I don't have the resources to buffer-up an arbitrarily large number of queries.
When a query comes in to the server, it arrives in the tcp_callback function. Data is arriving before I've fully sent the response to the previous one.
How do I impose some flow control on incoming data so that I can do things lock-step ?
of course you can stop data from coming in - just disable the respective interrupt for a short while. the client will eventually retransmit, because it won't receive an ACK from you for that packet. how about that? and of course you can manipulate the size of the sliding window and suggested here already, but at a performance cost.