[Buildroot] [PATCH 01/15] fs: add genimage infra

[Arnout Vandecappelle <arnout@mind.be>]

On 04/14/16 10:33, Peter Korsgaard wrote:
>>>>>> "Thomas" == Thomas Petazzoni <thomas.petazzoni@free-electrons.com> writes:
>
> Hi,
>
>>> # Make sure the genimage dependencies appear in graph-depends
>   >> show-targets:
>   >> @echo $(ROOTFS_GENIMAGE_DEPENDENCIES)
>
>   > But then is it really something that belongs to fs/ ? It really isn't a
>   > filesystem.
>
> No, it is closer to the post-image script. Where do you suggest to move
> it? system/?
>
>
>   >> However, I'm afraid that we're moving a bit too fast after all. There are
>   >> several open issues still:
>   >>
>   >> - Do post-image scripts come before or after genimage?
>   >> - What with the dosfstools/mtools dependency?
>   >> - Should we support genimage.cfg files that are generated from a post-image script?
>   >> - Should we support several genimage.cfg files, producing several images (e.g. a
>   >> NAND and a SD image)?
>   >>
>   >> So, the current approach works well for the bundled defconfigs, but for real
>   >> use cases I think it's a bit too limited to be practical after all.
>
>   > Do we need to support all real use cases? I think we should support the
>   > common use cases, and the more complicated use cases can be handled via
>   > a special post-image script. That's really the general philosophy of
>   > Buildroot IMO: handle the most common cases nicely, and leave enough
>   > extension scripts/hooks to allow people to plug their scripts to handle
>   > the more complicated/specific cases.
>
> Agreed, but it is good to think about the questions Arnout listed to
> think about what is really the common use case.
>
> The definition of the post-image script was to run something at the very
> end, so I think we should do genimage before post-image (even though I
> could imagine use cases for the opposite as well).

  Yes, so eventually we'll have a post-rootfs script...

>
> For the dosfstools/mtools dependencies I think a simple sub option
> pulling them in is most sensible.
>
> Supporting multiple genimage.cfg files (like we do for device_tables /
> post-build / post-image, ..) IMHO makes sense and looks simple to do.

  Well, compared to the really simple solution that Ezequiel has now, I think 
the code will look quite a bit more complicated when there are multiple 
genimage.cfg files.


  Oh, and one more question: should we somehow make sure that the images 
generated by the different scripts don't have the same name?

  Regards,
  Arnout

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