How do I use layers to replacing system configuration files?

How do I use layers to replacing system configuration files?

[Chris Tapp]

I want to be able to change the contents of 'interfaces' in a way that  
means I don't have to change the meta/ tree. It looks like layers  
should do this for me (section 3.4.1 of the Poky Reference Manual),  
but I can't seem to get my files to take precedence.

For example, a default build for laverne-4.0.1 uses core-recipes/ 
netbase/netbase/qemux86/interfaces.

I've created an empty copy of the meta-emenlow layer, changed its  
layer.conf as required and added it in to bblayers.conf. I can tell  
this is getting picked up as I get a warning that it contains no .bb  
files (it will eventually).

However, my meta-new/packages/netbase/netbase/qemux86/interfaces file  
isn't overriding the one above.

What else do I need to do? Do I need to have something other that .bb  
and .bbappend added to BBPATH (or something else)?

Chris Tapp

opensource@keylevel.com
www.keylevel.com

Re: How do I use layers to replacing system configuration files?

[Gary Thomas]

On 02/20/2011 10:58 AM, Chris Tapp wrote:
> I want to be able to change the contents of 'interfaces' in a way that means I don't have to change the meta/ tree. It looks like layers should do this for me (section 3.4.1 of the
> Poky Reference Manual), but I can't seem to get my files to take precedence.
>
> For example, a default build for laverne-4.0.1 uses core-recipes/netbase/netbase/qemux86/interfaces.
>
> I've created an empty copy of the meta-emenlow layer, changed its layer.conf as required and added it in to bblayers.conf. I can tell this is getting picked up as I get a warning
> that it contains no .bb files (it will eventually).
>
> However, my meta-new/packages/netbase/netbase/qemux86/interfaces file isn't overriding the one above.
>
> What else do I need to do? Do I need to have something other that .bb and .bbappend added to BBPATH (or something else)?

You'll need a meta-new/packages/netbase/netbase_4.44.bbappend file which
tells bitbake where to find your override files.  I do this all the time,
for example, I have a board with two targets:
   $ tree meta-ppc/packages/netbase/
   meta-ppc/packages/netbase/
   ├── netbase-4.44
   │   ├── cobra
   │   │   ├── interfaces
   │   └── ppc8379
   │       ├── interfaces
   └── netbase_4.44.bbappend
   $ cat meta-ppc/packages/netbase/netbase_4.44.bbappend
   THISDIR := "${@os.path.dirname(bb.data.getVar('FILE', d, True))}"
   FILESPATH =. "${@base_set_filespath(["${THISDIR}/${PN}-${PV}"], d)}:"

-- 
------------------------------------------------------------
Gary Thomas                 |  Consulting for the
MLB Associates              |    Embedded world
------------------------------------------------------------

Re: How do I use layers to replacing system configuration files?

[Chris Tapp]

On 20 Feb 2011, at 18:04, Gary Thomas wrote:

> You'll need a meta-new/packages/netbase/netbase_4.44.bbappend file  
> which
> tells bitbake where to find your override files.  I do this all the  
> time,
> for example, I have a board with two targets:
>  $ tree meta-ppc/packages/netbase/
>  meta-ppc/packages/netbase/
>  ├── netbase-4.44
>  │   ├── cobra
>  │   │   ├── interfaces
>  │   └── ppc8379
>  │       ├── interfaces
>  └── netbase_4.44.bbappend
>  $ cat meta-ppc/packages/netbase/netbase_4.44.bbappend
>  THISDIR := "${@os.path.dirname(bb.data.getVar('FILE', d, True))}"
>  FILESPATH =. "${@base_set_filespath(["${THISDIR}/${PN}-${PV}"], d)}:"

Thanks. I was just looking at .bbappend when your message arrived ;-)

Section 4.8 of the Poky Reference Manual shows an even easier way of  
doing what I need. All the .bbappend has is:

FILESEXTRAPATHS := "${THISDIR}/${PN}"

Chris

Re: How do I use layers to replacing system configuration files?

[Gary Thomas]

On 02/20/2011 11:23 AM, Chris Tapp wrote:
> On 20 Feb 2011, at 18:04, Gary Thomas wrote:
>
>> You'll need a meta-new/packages/netbase/netbase_4.44.bbappend file which
>> tells bitbake where to find your override files. I do this all the time,
>> for example, I have a board with two targets:
>> $ tree meta-ppc/packages/netbase/
>> meta-ppc/packages/netbase/
>> ├── netbase-4.44
>> │ ├── cobra
>> │ │ ├── interfaces
>> │ └── ppc8379
>> │ ├── interfaces
>> └── netbase_4.44.bbappend
>> $ cat meta-ppc/packages/netbase/netbase_4.44.bbappend
>> THISDIR := "${@os.path.dirname(bb.data.getVar('FILE', d, True))}"
>> FILESPATH =. "${@base_set_filespath(["${THISDIR}/${PN}-${PV}"], d)}:"
>
> Thanks. I was just looking at .bbappend when your message arrived ;-)
>
> Section 4.8 of the Poky Reference Manual shows an even easier way of doing what I need. All the .bbappend has is:
>
> FILESEXTRAPATHS := "${THISDIR}/${PN}"

That would be great (if it works).  My recipes are based on examples
which were available when the .bbappend and layers were first introduced.

-- 
------------------------------------------------------------
Gary Thomas                 |  Consulting for the
MLB Associates              |    Embedded world
------------------------------------------------------------

Re: How do I use layers to replacing system configuration files?

[Chris Tapp]

On 20 Feb 2011, at 18:27, Gary Thomas wrote:

> On 02/20/2011 11:23 AM, Chris Tapp wrote:
>>
>> FILESEXTRAPATHS := "${THISDIR}/${PN}"
>
> That would be great (if it works).  My recipes are based on examples
> which were available when the .bbappend and layers were first  
> introduced.

It's working for me ;-)

Chris