[libcamera-devel] [SimpleCam PATCH] cmake: Provide a sample CMakeLists.txt

[Kieran Bingham]

Quoting Laurent Pinchart (2022-08-09 14:00:38)
> Hi Kieran,
> 
> Thank you for the patch.
> 
> On Tue, Aug 09, 2022 at 01:10:44PM +0100, Kieran Bingham via libcamera-devel wrote:
> > While libcamera uses meson as its build infrastructure, applications are
> > free to use other make systems. CMake is widely used, so add an example
> > CMakeLists.txt to support building simple-cam and linking against
> > libcamera using cmake.
> > 
> > Signed-off-by: Kieran Bingham <kieran.bingham at ideasonboard.com>
> > ---
> >  CMakeLists.txt | 32 ++++++++++++++++++++++++++++++++
> >  1 file changed, 32 insertions(+)
> >  create mode 100644 CMakeLists.txt
> > 
> > diff --git a/CMakeLists.txt b/CMakeLists.txt
> > new file mode 100644
> > index 000000000000..fc8e734bdf59
> > --- /dev/null
> > +++ b/CMakeLists.txt
> > @@ -0,0 +1,32 @@
> > +cmake_minimum_required(VERSION 3.6)
> > +
> > +project(SimpleCam
> > +     VERSION 1.0
> 
> Should meson.build also set version to 1.0 ?

I don't think I care about it ;-)

I think I can drop the statement.

> > +     DESCRIPTION "A small and documented example application for libcamera"
> > +     LANGUAGES CXX)
> > +
> > +#set (CMAKE_EXPORT_COMPILE_COMMANDS ON)
> 
> Should this line be dropped ? If you want to keep it as an example, I
> would add a comment before it.

Yes, this is just a leftover.

> > +set (CMAKE_CXX_STANDARD 17)
> > +
> > +find_package(PkgConfig)
> > +
> > +pkg_check_modules(LIBCAMERA REQUIRED IMPORTED_TARGET libcamera)
> > +message(STATUS "libcamera library found:")
> > +message(STATUS "    version: ${LIBCAMERA_VERSION}")
> > +message(STATUS "    libraries: ${LIBCAMERA_LINK_LIBRARIES}")
> > +message(STATUS "    include path: ${LIBCAMERA_INCLUDE_DIRS}")
> > +
> > +# libevent is used specifically by simple-cam as it's event loop.
> 
> s/it's/its/
> 
> > +# Applications may use a different event handling implementation.
> > +pkg_check_modules(LIBEVENT REQUIRED IMPORTED_TARGET libevent_pthreads)
> > +message(STATUS "libevent_pthreads library found:")
> > +message(STATUS "    version: ${LIBEVENT_VERSION}")
> > +message(STATUS "    libraries: ${LIBEVENT_LINK_LIBRARIES}")
> > +message(STATUS "    include path: ${LIBEVENT_INCLUDE_DIRS}")
> > +
> > +include_directories(${CMAKE_SOURCE_DIR} ${LIBCAMERA_INCLUDE_DIRS} ${LIBEVENT_INCLUDE_DIRS})
> > +
> > +add_executable(simple-cam simple-cam.cpp event_loop.cpp)
> > +
> > +target_link_libraries(simple-cam PkgConfig::LIBEVENT)
> > +target_link_libraries(simple-cam PkgConfig::LIBCAMERA)
> 
> Could you also add the following compiler flags to match what we do in
> meson.build ?

Yes, I'll figure out how to add it.

> 
> -Wall
> -Winvalid-pch
> -Wnon-virtual-dtor
> -Wextra
> -Werror
> -Wno-unused-parameter
> 
> -- 
> Regards,
> 
> Laurent Pinchart