On Mon, Apr 11, 2022 at 12:48:59PM +0300, Ilpo Järvinen wrote:
> Use n_tty_receive_char_flow_ctrl also on the closing path. This makes
> the code cleaner and consistent.
>
> However, there a small change of regression!
>
> The earlier closing path has a small difference compared with the
> normal receive path. If START_CHAR and STOP_CHAR are equal, their
> precedence is different depending on which path a character is
> processed. I don't know whether this difference was intentional or
> not, and if equal START_CHAR and STOP_CHAR is actually used anywhere.
> But it feels not so useful corner case.
>
> While this change would logically belong to those earlier changes,
> having a separate patch for this is useful. If this regresses, bisect
> can pinpoint this change rather than the large patch. Also, this
> change is not necessary to minimal fix for the issue addressed in
> the previous patch.
This is nice, if it flies!
FWIW,
Reviewed-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx>
> ---
> drivers/tty/n_tty.c | 13 ++++---------
> 1 file changed, 4 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/tty/n_tty.c b/drivers/tty/n_tty.c
> index fede29ed8daf..e6f47858f98f 100644
> --- a/drivers/tty/n_tty.c
> +++ b/drivers/tty/n_tty.c
> @@ -1414,15 +1414,10 @@ static void n_tty_receive_char_closing(struct tty_struct *tty, unsigned char c,
> c = tolower(c);
>
> if (I_IXON(tty)) {
> - if (c == STOP_CHAR(tty)) {
> - if (!lookahead_done)
> - stop_tty(tty);
> - } else if (c == START_CHAR(tty) && lookahead_done) {
> - return;
> - } else if (c == START_CHAR(tty) ||
> - (tty->flow.stopped && !tty->flow.tco_stopped && I_IXANY(tty) &&
> - c != INTR_CHAR(tty) && c != QUIT_CHAR(tty) &&
> - c != SUSP_CHAR(tty))) {
> + if (!n_tty_receive_char_flow_ctrl(tty, c, lookahead_done) &&
> + 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);
> }
> --
> 2.30.2
>
--
With Best Regards,
Andy Shevchenko
