[yocto] Crosscompiling python extensions with yocto generated toolchains!?

[Daniel.]

The above script can also be founded here:
https://gist.github.com/gkos/2fa8dd54712d0b92a3db52e472d9fc09

Regards,

2016-06-22 11:57 GMT-03:00 Daniel. <danielhilst at gmail.com>:
> Well, I've create a little script to create the needed variables used
> by Yocto's python.
>
> Here it is:
>
> . $1
> export BUILD_SYS=$(echo $CONFIGURE_FLAGS | tr -s ' ' '\n' | grep host
> | cut -f2 -d=)
> export HOST_SYS=$(echo $CONFIGURE_FLAGS | tr -s ' ' '\n' | grep build
> | cut -f2 -d=)
> export STAGING_INCDIR=${OECORE_TARGET_SYSROOT}/usr/include
> export STAGING_LIBDIR=${OECORE_TARGET_SYSROOT}/usr/lib
> export PATH=${OECORE_NATIVE_SYSROOT}/usr/bin/python-native:${PATH}
>
> I save it to a file and source it passing the environment-setup-*
> scritp that lives at my ${TMPDIR} folder.
>
> After that I can crosscompile python extension to my target as usual
> with `python setup.py build'
>
>
> Regards,
>
>
> 2016-06-20 17:43 GMT-03:00 Daniel. <danielhilst at gmail.com>:
>> My first doubt was how to trully cross-compile python extensions. Since I
>> can't find anything usefull on internet I ask my self: How OE does it? It
>> seems that OE uses an patched distutils to get bits build. This "assumption"
>> comes from what I see at distutils/sysconfig.py that lives at
>> build/tmp/sysroot/.. folder. After more digging I found this patch:
>> http://git.yoctoproject.org/cgit.cgi/poky/tree/meta/recipes-devtools/python/python-native/12-distutils-prefix-is-inside-staging-area.patch?h=daisy
>>
>> The variables are aplied by this patch to the python-native (since I'm still
>> in Daisy, shame on me). At the top of the patch we see:
>>
>> The proper prefix is inside our staging area.
>>
>> So I'll try to contact these people to track the "proper fix". Since
>> crosscompiling python extensions is lacking of
>>
>> documentation reading the source and talking to the gurus is the only option
>> avaible right now :) .
>>
>>
>> Regards,
>>
>>
>>
>> 2016-06-20 16:23 GMT-03:00 Khem Raj <raj.khem at gmail.com>:
>>>
>>> On Mon, Jun 20, 2016 at 12:08 PM, Daniel. <danielhilst at gmail.com> wrote:
>>> > I've found this recipe "python-pycurl" with exports libcurl to python.
>>> > What
>>> > I did was build it and take a look at temp folder to stalk what line is
>>> > used
>>> > to compile that stuff. Here it is:
>>> >
>>> > distutils_do_compile() {
>>> >
>>> >
>>> > STAGING_INCDIR=/home/geckos/yocto/yocto-daisy/build_x11/tmp/sysroots/pharosserver-imx6/usr/include
>>> > \
>>> >
>>> >
>>> > STAGING_LIBDIR=/home/geckos/yocto/yocto-daisy/build_x11/tmp/sysroots/pharosserver-imx6/usr/lib
>>> > \
>>> >          BUILD_SYS=x86_64-linux HOST_SYS=arm-poky-linux-gnueabi \
>>> >
>>> >
>>> > /home/geckos/yocto/yocto-daisy/build_x11/tmp/sysroots/x86_64-linux/usr/bin/python-native/python
>>> > setup.py build  || \
>>> >          bbfatal "python setup.py build_ext execution failed."
>>> >
>>> > }
>>> >
>>> >
>>> > So I go to my extension's source folder and paste
>>> >
>>> > STAGING_INCDIR=/home/geckos/yocto/yocto-daisy/build_x11/tmp/sysroots/pharosserver-imx6/usr/include
>>> > \
>>> >
>>> > STAGING_LIBDIR=/home/geckos/yocto/yocto-daisy/build_x11/tmp/sysroots/pharosserver-imx6/usr/lib
>>> > \
>>> > BUILD_SYS=x86_64-linux HOST_SYS=arm-poky-linux-gnueabi \
>>> >
>>> > /home/geckos/yocto/yocto-daisy/build_x11/tmp/sysroots/x86_64-linux/usr/bin/python-native/python
>>> > setup.py build
>>> >
>>> > and everything works fine, I got my extension compiled. So, in what
>>> > magic
>>> > are these enviroment variables envolved? STAGING_INCDIR
>>> > and STAGING_LIBDIR are OE stuff, what are these BUILD_SYS and HOST_SYS
>>> > related?! I'm still searching, anyway thanks Khen for
>>> > pointing me meta-python sources. It helped me a lot.
>>>
>>>
>>> OE has several classes where common operations are abstracted out and
>>> you can see that in recipes
>>> e.g. inherit setuptools etc. you should copy the recipe which is
>>> closest to your package and modify it
>>> to use your package source etc. and make other needed tweaks.
>>>
>>> >
>>> > Regards,
>>> >
>>> >
>>> > 2016-06-20 15:29 GMT-03:00 Daniel. <danielhilst at gmail.com>:
>>> >>
>>> >> Thank you Khem!!
>>> >>
>>> >> Regards,
>>> >>
>>> >> 2016-06-20 15:02 GMT-03:00 Khem Raj <raj.khem at gmail.com>:
>>> >>>
>>> >>> On Mon, Jun 20, 2016 at 10:44 AM, Daniel. <danielhilst at gmail.com>
>>> >>> wrote:
>>> >>> > Hi everybody..
>>> >>> >
>>> >>> > I've been playing with python extensions. Now I want to compile a
>>> >>> > simple
>>> >>> > hello world extension
>>> >>> > to my Yocto's target, but I really can't find any good resource
>>> >>> > about
>>> >>> > doing
>>> >>> > it. So what is the teory behind it?
>>> >>> >
>>> >>> > I know that I need python headers "Python.h and others" and that I
>>> >>> > need
>>> >>> > distutils installed. After that everything is done by distutils and
>>> >>> > setup.py
>>> >>> > script, but what is done is a mistery. I found distutilscross on
>>> >>> > internet
>>> >>> > but no documentation about it!?
>>> >>> >
>>> >>> > How are python extensions cross-compiled by Yocto? Can somebody
>>> >>> > point
>>> >>> > me an
>>> >>> > example?!
>>> >>>
>>> >>> take a look at meta-python.
>>> >>>
>>> >>> http://cgit.openembedded.org/meta-openembedded/tree/meta-python
>>> >>>
>>> >>> You might find some examples close to what you are looking for.
>>> >>>
>>> >>> >
>>> >>> > Regards,
>>> >>> >
>>> >>> > --
>>> >>> > "Do or do not. There is no try"
>>> >>> >   Yoda Master
>>> >>> >
>>> >>> > --
>>> >>> > _______________________________________________
>>> >>> > yocto mailing list
>>> >>> > yocto at yoctoproject.org
>>> >>> > https://lists.yoctoproject.org/listinfo/yocto
>>> >>> >
>>> >>
>>> >>
>>> >>
>>> >>
>>> >> --
>>> >> "Do or do not. There is no try"
>>> >>   Yoda Master
>>> >
>>> >
>>> >
>>> >
>>> > --
>>> > "Do or do not. There is no try"
>>> >   Yoda Master
>>
>>
>>
>>
>> --
>> "Do or do not. There is no try"
>>   Yoda Master
>
>
>
> --
> "Do or do not. There is no try"
>   Yoda Master



-- 
"Do or do not. There is no try"
  Yoda Master