The event loop reads through open_stream(), which takes the socket out
of the Client, so the client_.stop() in stop() could not reach it.
stop(), and the destructor with it, waited until the server sent
something or the read timeout passed, 300 seconds by default.
The loop now hands the stream's socket to stop() while it reads, and
withdraws it under the same lock before the socket is closed. stop()
shuts down the read side only: a TLS backend answers the EOF with an
alert, and writing it to a socket closed for writing raises SIGPIPE.
yhirose
3744227de2
