On Fri, 8 Apr 2022, Andy Shevchenko wrote:
> On Fri, Apr 08, 2022 at 02:39:53PM +0300, Ilpo Järvinen wrote:
> > After lookahead for XON/XOFF characters is added by the next
> > patch, the receive side needs to ensure the flow-control
> > actions are not retaken later on when those same characters
> > get read by TTY.
> >
> > Thus, pass lookahead count to receive_buf and skip
> > flow-control character actions if already taken for the
> > character in question. Lookahead count will become live after
> > the next patch.
>
> ...
>
> > + if (c == STOP_CHAR(tty)) {
> > + if (!lookahead_done)
>
> But now it can be as below
>
> if (c == STOP_CHAR(tty) && !lookahead_done)
>
> > + stop_tty(tty);
> > + } else if ((c == START_CHAR(tty) && !lookahead_done) ||
> > (tty->flow.stopped && !tty->flow.tco_stopped && I_IXANY(tty) &&
> > c != INTR_CHAR(tty) && c != QUIT_CHAR(tty) &&
> > c != SUSP_CHAR(tty))) {
Are you sure about this? ...If I make that change to the first if, the
second part of the else if's condition get a chance it didn't have
previously.
What I'd like to do here is to take advantage of the function that was
added:
if (!n_tty_receive_char_flow_ctrl(tty, c) &&
tty->flow.stopped && !tty->flow.tco_stopped && I_IXANY(tty) &&
c != INTR_CHAR(tty) && c != QUIT_CHAR(tty) &&
c != SUSP_CHAR(tty))) {
start_tty(tty);
process_echoes(tty);
}
...but it will change STOP_CHAR vs START_CHAR precedence for the case
where they're the same characters. I don't know if it matters.
--
i.
