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lexus2k / tinyproto

Tiny Software Protocol for communication over UART, SPI, etc
GNU General Public License v3.0
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Connection breaks down if nothing is sent for >= keep alive timeout #40

Open chenlijun99 opened 2 years ago

chenlijun99 commented 2 years ago

I would expect Tinyproto to schedule some S frames as keep alive frames.

lexus2k commented 1 year ago

Tinyproto already has this:

https://github.com/lexus2k/tinyproto/blob/164eecebcda1734469456f98c910494534e53483/src/proto/fd/tiny_fd.c#L999

If you consider a bug, let me know

chenlijun99 commented 1 year ago

Hi. Sorry for the lack of feedback.

Indeed, there is already a mechanism to send keep alive frames. I can see that sometimes it works, sometimes it doesn't. If I understand the code correctly, once a keep alive frame has been sent, if tiny_fd_connected_check_idle_timeout is immediately re-called (because tiny_fd_get_tx_data is immediately re-called), before the response to the keep alive frame is received, then we immediately enter this branch

https://github.com/lexus2k/tinyproto/blob/164eecebcda1734469456f98c910494534e53483/src/proto/fd/tiny_fd.c#L1001-L1005

and disconnection is asserted.

Maybe a sort of keepalive response timeout should be considered?