[PATCH xf86-input-synaptics] syndaemon: enable touchpad when pressing a modifier combo

[Peter Hutterer]

On Mon, Aug 01, 2016 at 10:54:29AM +0200, Anton Lindqvist wrote:
> I run syndaemon with the -K option and often find myself in the
> following scenario: I'm typing non modifier combos in my terminal, only
> to later press a modifier combo causing my WM to switch application, the
> touchpad is then disabled due to my previous typing. I find this
> annoying and therefore propose the following change: enable the touchpad
> immediately once a modifier combo is detected. This is done by adding a
> third possible return value from keyboard_activity causing the main loop
> to reset the timestamp of the last activity which will cause the
> touchpad to be enabled.

seems like a sensible addition, thanks.

> Any feedback would be much appreciated and don't forget to bring your
> scissor if you decide to apply this patch.
> 
> >8------------8<
> 
> When ignoring modifier combos enable the touchpad immediately when a
> such a combo is detected.

typo "a such"
and I wouldn't mind a bit more details on when it enables/disables the
touchpad because I had to read to code and test to figure it out. that's
what the commit message should relay. You're using modifier combo in a
couple of different ways which is confusing. in the syndaemon context, the
modifier combo means modifers + keys but your patch re-enables the touchpad
as soon as *any* modifier is pressed.

please explain this in the commit message.

> 
> Signed-off-by: Anton Lindqvist <anton.lindqvist at gmail.com>
> ---
>  tools/syndaemon.c | 19 +++++++++++++++----
>  1 file changed, 15 insertions(+), 4 deletions(-)
> 
> diff --git a/tools/syndaemon.c b/tools/syndaemon.c
> index 29e75f5..021bf2a 100644
> --- a/tools/syndaemon.c
> +++ b/tools/syndaemon.c
> @@ -182,7 +182,9 @@ install_signal_handler(void)
>  }
>  
>  /**
> - * Return non-zero if the keyboard state has changed since the last call.
> + * Return 1 if the keyboard state has changed since the last call, -1 if
> + * the keyboard state contains a new modifier combo since the last call or 0
> + * otherwise.
>   */

let's define an enum and use that, much more expressive than random integer
values. ACTIVITY_NONE, ACTIVITY_MODIFIER, ACTIVITY_KEY or something.

>  static int
>  keyboard_activity(Display * display)
> @@ -203,7 +205,10 @@ keyboard_activity(Display * display)
>      if (ignore_modifier_combos) {
>          for (i = 0; i < KEYMAP_SIZE; i++) {
>              if (key_state[i] & ~keyboard_mask[i]) {
> -                ret = 0;
> +                if (old_key_state[i] & ~keyboard_mask[i])
> +                    ret = 0;
> +                else
> +                    ret = -1;
>                  break;
>              }
>          }
> @@ -232,8 +237,14 @@ main_loop(Display * display, double idle_time, int poll_delay)
>  
>      for (;;) {
>          current_time = get_time();
> -        if (keyboard_activity(display))
> -            last_activity = current_time;
> +        switch (keyboard_activity(display)) {
> +            case 1:
> +                last_activity = current_time;
> +                break;
> +            case -1:
> +                last_activity = 0.0;
> +                break;
> +        }
>  
>          /* If system times goes backwards, touchpad can get locked. Make
>           * sure our last activity wasn't in the future and reset if it was. */

syndaemon has 2 modes, one uses the RECORD extension (iirc that's the one
used by GNOME until recently). Please add the same functionality to the
RECORD mode as well.

Cheers,
   Peter