understanding overlays

understanding overlays

[Steffen Sledz]

I'm not really familiar with the oe/bitbake overlay details. So please forgive me if this is a faq. ;-)

Is the overlay package or file based?

Or in other words is the following scenario possible?

base layer:

  recipes/
    foo/
      foo.inc
      foo_x.y.z.bb

overlay:

  recipes/
    foo/
      foo.inc

And than build foo-x.y.z with the foo.inc from the overlay.

Steffen

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Re: understanding overlays

[Chris Larson]

On Wed, Jul 27, 2011 at 7:24 AM, Steffen Sledz <sledz@dresearch-fe.de> wrote:
> I'm not really familiar with the oe/bitbake overlay details. So please forgive me if this is a faq. ;-)
>
> Is the overlay package or file based?
>
> Or in other words is the following scenario possible?
>
> base layer:
>
>  recipes/
>    foo/
>      foo.inc
>      foo_x.y.z.bb
>
> overlay:
>
>  recipes/
>    foo/
>      foo.inc
>
> And than build foo-x.y.z with the foo.inc from the overlay.

That depends. If the .bb does 'require foo.inc', then no, it will use
the local one. If it does 'require recipes/foo/foo.inc', then yes, it
will use the overlay one, assuming the overlay is before the main
layer in your BBLAYERS.
-- 
Christopher Larson
clarson at kergoth dot com
Founder - BitBake, OpenEmbedded, OpenZaurus
Maintainer - Tslib
Senior Software Engineer, Mentor Graphics

Re: understanding overlays

[Steffen Sledz]

On 27.07.2011 18:12, Chris Larson wrote:
> On Wed, Jul 27, 2011 at 7:24 AM, Steffen Sledz <sledz@dresearch-fe.de> wrote:
>> I'm not really familiar with the oe/bitbake overlay details. So please forgive me if this is a faq. ;-)
>>
>> Is the overlay package or file based?
>>
>> Or in other words is the following scenario possible?
>>
>> base layer:
>>
>>  recipes/
>>    foo/
>>      foo.inc
>>      foo_x.y.z.bb
>>
>> overlay:
>>
>>  recipes/
>>    foo/
>>      foo.inc
>>
>> And than build foo-x.y.z with the foo.inc from the overlay.
> 
> That depends. If the .bb does 'require foo.inc', then no, it will use
> the local one. If it does 'require recipes/foo/foo.inc', then yes, it
> will use the overlay one, assuming the overlay is before the main
> layer in your BBLAYERS.

Thx. What about files referenced e.g. in SRC_URI? I assume that always the ones from the 'highest' layer are used. Right?

-- 
DResearch Fahrzeugelektronik GmbH
Otto-Schmirgal-Str. 3, 10319 Berlin, Germany
Tel: +49 30 515932-237 mailto:sledz@dresearch-fe.de
Fax: +49 30 515932-299
Geschäftsführer: Dr. Michael Weber, Werner Mögle;
Amtsgericht Berlin Charlottenburg; HRB 130120 B;
Ust.-IDNr. DE273952058

Re: understanding overlays

[Khem Raj]

On Thursday, July 28, 2011 07:48:43 AM Steffen Sledz wrote:
> On 27.07.2011 18:12, Chris Larson wrote:
> > On Wed, Jul 27, 2011 at 7:24 AM, Steffen Sledz <sledz@dresearch-fe.de> 
wrote:
> >> I'm not really familiar with the oe/bitbake overlay details. So please
> >> forgive me if this is a faq. ;-)
> >> 
> >> Is the overlay package or file based?
> >> 
> >> Or in other words is the following scenario possible?
> >> 
> >> base layer:
> >>  recipes/
> >>  
> >>    foo/
> >>    
> >>      foo.inc
> >>      foo_x.y.z.bb
> >> 
> >> overlay:
> >>  recipes/
> >>  
> >>    foo/
> >>    
> >>      foo.inc
> >> 
> >> And than build foo-x.y.z with the foo.inc from the overlay.
> > 
> > That depends. If the .bb does 'require foo.inc', then no, it will use
> > the local one. If it does 'require recipes/foo/foo.inc', then yes, it
> > will use the overlay one, assuming the overlay is before the main
> > layer in your BBLAYERS.
> 
> Thx. What about files referenced e.g. in SRC_URI? I assume that always the
> ones from the 'highest' layer are used. Right?

It will consider the BBFILE_PRIORITY for recipe files. but .inc and other 
metadata are searched in order of paths in BBPATH

-- 
Khem Raj