[Buildroot] [PATCH] package/libgles: postpone the check for a missing GLES provider

[Arnout Vandecappelle <arnout@mind.be>]

On 17/12/13 23:35, Yann E. MORIN wrote:
> Arnout, All,
>
> On 2013-12-17 23:20 +0100, Arnout Vandecappelle spake thusly:
[snip]
>>   Here's a wild idea...
>>
>> In rpi-userland/Config.in:
>>
>> if BR2_PACKAGE_RPI_USERLAND
>> config BR2_PACKAGE_LIBEGL_PROVIDER
>> 	string
>> 	default "rpi-userland"
>> endif
>>
>> In opengl/libegl/libegl.mk:
>>
>> LIBEGL_DEPENDENCIES = $(call qstrip,$(BR2PACKAGE_LIBEGL_PROVIDER))
>>
>
> That's about what I am experimenting right now! :-p
>
> But I've done it slightly differently:
>
> package/opengl/libegl/Config.in:
>      config BR2_LIBEGL_PROVIDER
>          string
>
> package/rpi-userland/Config.in:
>      config BR2_LIBEGL_PROVIDER
>          default "rpi-userland" if BR2_PACKAGE_RPI_USERLAND
>
> And the same .mk fragment you suggested for libegl.

  Nice! I'm all for it! I didn't know it was allowed in Kconfig to define 
the same symbol twice. But indeed, we already do that in arch/


> My solution is a little bit more compact, and since it does not use a
> package-named variable, we can say that packages do not step on
> one-another's feet. Yet, a bit hackish, I have to concede...
>
>>
>>   It's still hackish of course, because:
>>
>> - rpi-userland/Config.in defines a symbol "belonging" to the libegl package;
>>
>> - only one provider can be defined, Kconfig will scream if it's defined
>> twice;
>
> Is it even valid to have two providers of the same functioanlity? What
> would happen: what libEGL.so would be used? Probably the last one
> installed, ie. the one from the alphabetically-last provider.

  Completely true. With your construct, if somehow two providers are 
selected, Kconfig will probably just give you the first-sourced provider.


  Regards,
  Arnout

>
>> - it may not work at all :-).
>
> I'll tell you when I'm done with my checks... ;-p
>
> Regards,
> Yann E. MORIN.
>


-- 
Arnout Vandecappelle                          arnout at mind be
Senior Embedded Software Architect            +32-16-286500
Essensium/Mind                                http://www.mind.be
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