[libcamera-devel] [PATCH] Documentation: fix createRequest unique_ptr

[Jacopo Mondi]

Hi Tommaso, Laurent

On Mon, Jun 13, 2022 at 12:07:27PM +0300, Laurent Pinchart via libcamera-devel wrote:
> Hi Tommaso,
>
> Thank you for the patch.
>
> On Mon, Jun 13, 2022 at 10:27:25AM +0200, Tommaso Merciai via libcamera-devel wrote:
> > camera->createRequest() function return std::unique_ptr<Request>, then
> > manipulate Request as std::unique_ptr.
> > This solve the following error, during compilation:
> >
> > error: cannot convert ‘std::unique_ptr<libcamera::Request>’ to ‘libcamera::Request*’ in initialization
> >
> > References:
> >  - https://github.com/kbingham/simple-cam/blob/bb97f3bbd96a9d347e1b7f6cb68d94efaf8db574/simple-cam.cpp#L369
>
> The change in simple-cam was made in
>
> commit 94b055c70c09729cab51cc2c74c1a0e3c1a9ae50
> Author: Paul Elder <paul.elder at ideasonboard.com>
> Date:   Fri Oct 16 14:51:19 2020 +0900
>
>     simple-cam: Reuse Requests
>
>     Update simple-cam to reuse Request objects, and use the new API with
>     unique pointers.
>
>     Signed-off-by: Paul Elder <paul.elder at ideasonboard.com>
>     Reviewed-by: Kieran Bingham <kieran.bingham at ideasonboard.com>
>     Signed-off-by: Kieran Bingham <kieran at bingham.xyz>
>
> which follows the introduction of the Request::reuse() API in libcamera.
> The application guide should thus be extended accordingly.
>
> Kieran, I notice that there are quite a few changes in simple-cam on top
> of commit 94b055c70c09. Have most of them been taken into account in the
> application guide, or do we need a larger update ?
>

We have more
https://patchwork.libcamera.org/project/libcamera/list/?series=3176

But this patch can be collected in the meantime ?

Reviewed-by: Jacopo Mondi <jacopo at jmondi.org>

Thanks
  j

> > Signed-off-by: Tommaso Merciai <tommaso.merciai at amarulasolutions.com>
> > ---
> >  Documentation/guides/application-developer.rst | 10 +++++-----
> >  1 file changed, 5 insertions(+), 5 deletions(-)
> >
> > diff --git a/Documentation/guides/application-developer.rst b/Documentation/guides/application-developer.rst
> > index 16bea9c4..8d12a208 100644
> > --- a/Documentation/guides/application-developer.rst
> > +++ b/Documentation/guides/application-developer.rst
> > @@ -308,7 +308,7 @@ the camera.
> >
> >     Stream *stream = streamConfig.stream();
> >     const std::vector<std::unique_ptr<FrameBuffer>> &buffers = allocator->buffers(stream);
> > -   std::vector<Request *> requests;
> > +   std::vector<std::unique_ptr<Request>> requests;
> >
> >  Proceed to fill the request vector by creating ``Request`` instances from the
> >  camera device, and associate a buffer for each of them for the ``Stream``.
> > @@ -316,7 +316,7 @@ camera device, and associate a buffer for each of them for the ``Stream``.
> >  .. code:: cpp
> >
> >         for (unsigned int i = 0; i < buffers.size(); ++i) {
> > -           Request *request = camera->createRequest();
> > +           std::unique_ptr<Request> request = camera->createRequest();
> >             if (!request)
> >             {
> >                 std::cerr << "Can't create request" << std::endl;
> > @@ -332,7 +332,7 @@ camera device, and associate a buffer for each of them for the ``Stream``.
> >                 return ret;
> >             }
> >
> > -           requests.push_back(request);
> > +           requests.push_back(std::move(request));
> >         }
> >
> >  .. TODO: Controls
> > @@ -517,8 +517,8 @@ and queue all the previously created requests.
> >  .. code:: cpp
> >
> >     camera->start();
> > -   for (Request *request : requests)
> > -       camera->queueRequest(request);
> > +   for (std::unique_ptr<Request> &request : requests)
> > +      camera->queueRequest(request.get());
> >
> >  Start an event loop
> >  ~~~~~~~~~~~~~~~~~~~
>
> --
> Regards,
>
> Laurent Pinchart