[libcamera-devel] [PATCH] build: Fix python dependency

[Martin Kletzander]

On Thu, Aug 11, 2022 at 05:36:41PM +0300, Laurent Pinchart wrote:
>On Thu, Aug 11, 2022 at 05:11:07PM +0300, Tomi Valkeinen via libcamera-devel wrote:
>> On 11/08/2022 13:54, Martin Kletzander via libcamera-devel wrote:
>> > Building with pycamera fails due to dependency search for 'python3'.  Fix that
>> > by using meson's python module which searches for the proper files and various
>> > versions.
>> >
>> > Signed-off-by: Martin Kletzander <nert.pinx at gmail.com>
>> > ---
>> >   src/py/libcamera/meson.build | 9 +++++----
>> >   1 file changed, 5 insertions(+), 4 deletions(-)
>> >
>> > diff --git a/src/py/libcamera/meson.build b/src/py/libcamera/meson.build
>> > index eb8845388692..cf2e9395de38 100644
>> > --- a/src/py/libcamera/meson.build
>> > +++ b/src/py/libcamera/meson.build
>> > @@ -1,8 +1,9 @@
>> >   # SPDX-License-Identifier: CC0-1.0
>> >
>> > -py3_dep = dependency('python3', required : get_option('pycamera'))
>> > +pymod = import('python')
>> > +py3 = pymod.find_installation('python3', required : get_option('pycamera'))
>> >
>> > -if not py3_dep.found()
>> > +if not py3.found()
>> >       pycamera_enabled = false
>> >       subdir_done()
>> >   endif
>> > @@ -60,7 +61,7 @@ pycamera_sources += custom_target('py_gen_formats',
>> >
>> >   pycamera_deps = [
>> >       libcamera_public,
>> > -    py3_dep,
>> > +    py3.dependency(),
>> >       pybind11_dep,
>> >   ]
>> >
>> > @@ -71,7 +72,7 @@ pycamera_args = [
>> >       '-DLIBCAMERA_BASE_PRIVATE',
>> >   ]
>> >
>> > -destdir = get_option('libdir') / ('python' + py3_dep.version()) / 'site-packages' / 'libcamera'
>> > +destdir = get_option('libdir') / ('python' + py3.language_version()) / 'site-packages' / 'libcamera'
>> >
>> >   pycamera = shared_module('_libcamera',
>> >                            pycamera_sources,
>>
>> There was a similar patch posted some time back:
>>
>> https://lists.libcamera.org/pipermail/libcamera-devel/2022-May/030423.html
>>

Oh, sorry for missing that.  I just started looking into libcamera and this was
the first thing I found when I wanted to build with pycamera.  I guess

>> This doesn't work when cross-compiling.
>
>Tomi, would you be able to resume discussions with the meson developers
>to see how this could be fixed ?
>

I guess this could be worked around in the meson file, but since pycamera
support is experimental I guess you want a cleaner solution and don't have to
work around it for now.  I'll see what can be done with meson.

Have a nice day,
Martin