[oe] Development and Open Embedded

[Chris Larson]

On Wed, May 6, 2009 at 2:33 PM, Michael Sundius <msundius at sundius.com> wrote:
> Hi,
>
> I'm helping my organization move our platform build
> infrastructure to better than the complicated and
> disparate make jumble of make files and tarballs
> that we currently use. I've integrated much of it
> to Open Embedded (basic root fs image, kernel, tools).
>
> This all works well, but it seems to me (a kernel hacker
> mostly) that the hacking cycle of code, compile, run
> is a bit difficult if you are working within the confines
> of source control systems.
>
> that is, say I modify a file within my kernel development (git)
> tree and then want to compile it. under OE, the whole tree is
> going to be copied to the sources dir, tarballed, and then
> extracted into the ${S} directory.  Further, when compiling,
> all the output files are left in the ${S} dir, instead of
> directing them to an output directory.
>
> I find that most of the engineers I know start to grumble when
> the have to wait any longer than status quo in any one of the
> steps for turning around a small change to their source. My
> experience is mostly inside the kernel, but I suppose other
> projects are similar on embedded systems.
>
> I'm wondering if anyone has done such a thing as creating a
> recipe that forgoes the "fetch" task and point the ${S} to
> a local devel tree.. then adds an extra onto the make command
> to place the object in another directory (maybe ${O})...
>
> Maybe people have solved this problem in other ways or a similar
> way. I'd love to get some insight into how this is done in
> other organizations... It would be great to beable to inherit
> a class that allows use of an efficient dev cycle.

I have a little class somewhere around here that did that.  Killed
fetch/unpack/patch, set S to ${TOPDIR}, set O to
${TOPDIR}/obj-${HOST_SYS} or so, redirect WORKDIR to
${TOPDIR}/somethingorother, etc.  It works very well.  You can then
add the recipe from the source tree to your BBFILES, or add your
development area to COLLECTIONS or so, and it mostly just works.
Cleaning up something like that would be a huge boon to the
application and kernel developer use cases, which are sadly not well
satisfied in current openembedded.
-- 
Chris Larson
clarson at kergoth dot com
clarson at mvista dot com
Founder - BitBake, OpenEmbedded, OpenZaurus
Maintainer - Tslib
Software Engineer
MontaVista Software, Inc.