[libcamera-devel] [PATCH 3/3] Documentation: application-developer: Add camera detection check

[Kieran Bingham]

On Mon, Sep 27, 2021 at 12:24:14AM +0300, Laurent Pinchart wrote:
> On Mon, Sep 27, 2021 at 12:21:08AM +0300, Laurent Pinchart wrote:
> > The simple-cam application has a check to ensure that at least one
> > camera is present before attempting to access the first camera, to avoid
> > a crash. Update the application developer's guide accordingly.
> > 
> > Signed-off-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
> > ---
> >  Documentation/guides/application-developer.rst | 9 ++++++++-
> >  1 file changed, 8 insertions(+), 1 deletion(-)
> > 
> > diff --git a/Documentation/guides/application-developer.rst b/Documentation/guides/application-developer.rst
> > index 41a7d88369be..11d3df15825b 100644
> > --- a/Documentation/guides/application-developer.rst
> > +++ b/Documentation/guides/application-developer.rst
> > @@ -109,9 +109,16 @@ the Camera Manager reports as available to applications.
> >  Camera devices are stored by the CameraManager in a list accessible by index, or
> >  can be retrieved by name through the ``CameraManager::get()`` function. The
> >  code below retrieves the name of the first available camera and gets the camera
> > -by name from the Camera Manager.
> > +by name from the Camera Manager, after making sure that at least one camera is
> > +available.
> >  
> >  .. code:: cpp
> 
> This is obviously missing a blank line here :-S I'll fix it in v2 (or
> when pushing if no v2 is otherwise needed).
> 

Reviewed-by: Kieran Bingham <kieran.bingham at ideasonboard.com>

> > +   if (cm->cameras().empty()) {
> > +       std::cout << "No cameras were identified on the system."
> > +                 << std::endl;
> > +       cm->stop();
> > +       return EXIT_FAILURE;
> > +   }
> >  
> >     std::string cameraId = cm->cameras()[0]->id();
> >     camera = cm->get(cameraId);
> 
> -- 
> Regards,
> 
> Laurent Pinchart

-- 
--
Kieran