iostream - cancel read_until_close

Hello,

I have a problem with switching a stream to TLS, it throws an exception saying that the stream is not idle. I guess it is because I have read_until_close called on it, so there is a read callback, but there is no actual data anywhere, so the stream could be switched to TLS.

Maybe the solution is to use another read method which reads only some amount of data, but the problem is that I don't have a clear condition on where to stop waiting for new data, the process can take time and it is governed by a state machine, regex would not work there, basically I am implementing an XMPP client lib on tornado.iostream

Any suggestions how to handle that? Is it possible to clear callbacks installed by read_until_close?

Start by reading the tornado.iostream implementation and the read_until_close behavior, then trace how a stream decides whether it is idle before switching to TLS. The issue would be resolved when the supported behavior for cancelling or replacing that pending read is defined and covered by appropriate tests.