[libcamera-devel] [simple-cam PATCH 0/4] simple-cam: Update to latest API usage

[Kieran Bingham]

Hi Laurent,

On 24/09/2020 04:14, Laurent Pinchart wrote:
> Hi Kieran,
> 
> Thank you for the patches.
> 
> On Wed, Sep 23, 2020 at 05:44:08PM +0100, Kieran Bingham wrote:
>> The simple-cam app needs to be updated with a few API updates to work on
>> the latest libcamera builds.
>>
>> This is based on the code at https://github.com/kbingham/simple-cam
>> though I hope to move this to a more official location soon.
> 
> For the whole series,
> 
> Reviewed-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
> 
> It would be interesting to test-compile simple-cam when libcamera gains
> new commits. It can probably wait until libcamera itself gets CI though
> :-)

This is something I've been working on.

There are two options, an easy way and a hard way (to do this without
installing the library on each build).

The hard way (which is of course what was recommended in #meson) is to
provide a meson wrap for libcamera, so that it can be a subproject to
simple-cam. This means if libcamera is not found as a dependency it will
clone libcamera, build it - and automatically link against it statically.

It doesn't work - due to faults in our set up of the build system and
incorrect usage of things like meson.build_root() and meson.source_root().

My conversation led to one of the meson devs deciding to mark those as
deprecated :
 (See https://github.com/mesonbuild/meson/pull/7772)

Anyway, the easy and quick way - is that meson creates a pkg-config
'-uninstalled' location at $BUILD/meson-uninstalled ... and it's really
easy to build an app against an uninstalled library by pointing
PKG_CONFIG_DIR=$BUILD/meson-uninstalled

So that's a really quick and effective way of also compiling the
'external' simple-cam against a 'just built' libcamera.

I'm adding that to my daily builder, (the one that also does a
coverity-scan build, and a full matrix build of all compilers on my
laptop) - so I'll know as soon as there is breakage.

And indeed, sometime we'll move this to a more fully handled CI system too.

Anyway, thanks for the review, I'll push these patches to my repo.

--
Kieran



> 
>> Kieran Bingham (4):
>>   simple-cam: Use the new BufferMap interface
>>   simple-cam: Use a const stream
>>   meson: Remove incorrect default
>>   meson: Update to C++17
>>
>>  meson.build    | 3 +--
>>  simple-cam.cpp | 4 ++--
>>  2 files changed, 3 insertions(+), 4 deletions(-)
> 

-- 
Regards
--
Kieran