Philip Withnall authored Jun 23, 2015 and Olivier Crête committed Jun 03, 2016

Correct the behaviour of pseudo_tcp_socket_get_available_bytes() and
pseudo_tcp_get_available_send_space() when the socket is not in
TCP_ESTABLISHED state. It’s still permissible to send and receive up
until the local side calls pseudo_tcp_socket_close(), which means we
may be in state TCP_ESTABLISHED *or TCP_CLOSE_WAIT*.