On Mon, Apr 11, 2022 at 12:48:56PM +0300, Ilpo Järvinen wrote:
> Add a helper to check if the character is a flow control one.
> Reorder return places, add else for the case where START_CHAR
> and STOP_CHAR are the same, w/o else both would match.
>
> This seems cleanest approach once skipping due to lookahead
> is added by the next patch. Its downside is the duplicated
> START_CHAR and STOP_CHAR checks.
>
> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx>
> ---
> drivers/tty/n_tty.c | 15 ++++++++++-----
> 1 file changed, 10 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/tty/n_tty.c b/drivers/tty/n_tty.c
> index c7edfc001fd0..90b3e06cbeb1 100644
> --- a/drivers/tty/n_tty.c
> +++ b/drivers/tty/n_tty.c
> @@ -1220,20 +1220,25 @@ n_tty_receive_signal_char(struct tty_struct *tty, int signal, unsigned char c)
> process_echoes(tty);
> }
>
> +static bool n_tty_is_char_flow_ctrl(struct tty_struct *tty, unsigned char c)
> +{
> + return c == START_CHAR(tty) || c == STOP_CHAR(tty);
> +}
> +
> /* Returns true if c is consumed as flow-control character */
> static bool n_tty_receive_char_flow_ctrl(struct tty_struct *tty, unsigned char c)
> {
> + if (!n_tty_is_char_flow_ctrl(tty, c))
> + return false;
> +
> if (c == START_CHAR(tty)) {
> start_tty(tty);
> process_echoes(tty);
> - return true;
> - }
> - if (c == STOP_CHAR(tty)) {
> + } else if (c == STOP_CHAR(tty)) {
The else is always true here now so why check it again?
Just return in the above if statement and then call stop_tty().
thanks,
greg k-h
