[PATCH v1] libcamera: controls: Arrays of arrays are not supported

[Laurent Pinchart]

Hi Barnabás,

Thank you for the patch.

The subject line should tell what the patch does.

On Wed, Apr 23, 2025 at 03:02:14PM +0100, Kieran Bingham wrote:
> Quoting Barnabás Pőcze (2025-04-22 13:44:01)
> > Arrays of arrays, even arrays of strings, are not supported by
> > the current `ControlValue` mechanism, so disable them for now
> > to trigger comptime errors if attempts are made to use them.

s/comptime/compile-time/

> This sounds safer than discovering the fault at runtime!
> 
> Reviewed-by: Kieran Bingham <kieran.bingham at ideasonboard.com>
> 
> > Signed-off-by: Barnabás Pőcze <barnabas.pocze at ideasonboard.com>
> > ---
> >  include/libcamera/controls.h | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/include/libcamera/controls.h b/include/libcamera/controls.h
> > index 326452540..427517a02 100644
> > --- a/include/libcamera/controls.h
> > +++ b/include/libcamera/controls.h
> > @@ -121,7 +121,7 @@ struct control_type<Point> {
> >  };
> >  
> >  template<typename T, std::size_t N>
> > -struct control_type<Span<T, N>> : public control_type<std::remove_cv_t<T>> {
> > +struct control_type<Span<T, N>, std::enable_if_t<control_type<std::remove_cv_t<T>>::size == 0>> : public control_type<std::remove_cv_t<T>> {

Maybe with a bit of line wrap,

Reviewed-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>

> >         static constexpr std::size_t size = N;
> >  };
> >  

-- 
Regards,

Laurent Pinchart