Re: [gentoo-portage-dev] Re: running ebuild in src tree

[Joakim Tjernlund]

On Thu, 2015-03-12 at 01:27 +0000, Duncan wrote:
> Zac Medico posted on Wed, 11 Mar 2015 12:03:10 -0700 as excerpted:
>
> > On 03/11/2015 11:56 AM, Joakim Tjernlund wrote:
> > > On Wed, 2015-03-11 at 11:34 -0700, Zac Medico wrote:
> > > > On 03/11/2015 09:03 AM, Joakim Tjernlund wrote:
> > > > > When developing code it would be really nice if one could run your ebuild on that src tree as is(no
> > > > > fetch, unpack etc.)
> > > >
> > > > The existing convention is to create an ebuild with version 9999 and use one of the live vcs eclasses
> > > > such as git-r3 to pull the live sources in the src_unpack function. In a future EAPI, we plan to add
> > > > some features related to this [1].
> > >
> > > I think you misunderstand, [1] is not what I want to do(I think):
> > >
> > > Got my src working copy and made a few modds, not commitet yet. Now I just want build/test etc. before
> > > committing and to do that I just run mytree/overlay/dev-util/myapp/myapp.ebuild compile and voila, my
> > > code is built which I already have in mytree.
> >
> > Well, you can create a -9999 ebuild that copies your sources from $directory to $WORKDIR. Maybe use an
> > environment to configure whether it pulls from a local directory or a vcs repository.
>
> @ Joakim T:
>
> FWIW, a commonly recommended user-level portage optimization is to point
> $PORTAGE_TMPDIR at a tmpfs mount.  As long as you have sufficient memory,
> that lets all building take place in the tmpfs and thus in memory,  eliminating many read-accesses and
> most/all write accesses to permanent  storage during the build and (fake-)install phases.
>
> In addition to speeding up emerge itself, this reduces build-time I/O,  which often becomes the bottleneck
> on which other processes may be  waiting as well, thus allowing other processes more efficient access to
> permanent storage while emerge is ongoing.  Between this and setting  PORTAGE_NICENESS=20, emerge is /much/
> better behaved during builds,  interrupting other processes much less and thus letting you carry on with
> other things while emerge is doing its thing, with far less interruption.
> =:^)
>
> For instance, here I have /tmp as a tmpfs mount (with /var/tmp being a  bind-mount of the same tmpfs), and
> in make.conf, have the line:
>
> PORTAGE_TMPDIR=/tmp
>
> Emerge then creates /tmp/portage, and within it, creates the usual cat/ pkg/ build trees, etc, as it
> emerges various packages.
>
>
> Obviously, your sources in permanent storage are going to be cache-copied
> into memory as you do the build anyway, and pointing PORTAGE_TMPDIR at  tmpfs then becomes a copy to
> (tmpfs) memory only.  While that doesn't  technically eliminate the copies (since the read into tmpfs will
> cache  and you'll have the tmpfs copy as well), it DOES mean most of the work  beyond the initial read into
> memory will be memory-only, so you DO  eliminate the permanent-storage copies.
>
> Is that sufficiently close to what you were looking to do?  Beyond that,
> as Zac suggests, just have the ebuild grab the sources from wherever you
> put them as your src_unpack, as at that point it'll be a copy to tmpfs,  and thus take essentially the same
> time (or even less since it'll avoid  the build-time writes to permanent storage) as doing the in-place
> build  directly.  Plus, creating a tmpfs mount if necessary, and setting  PORTAGE_TMPDIR, is easy, and
> you'll dramatically speed-up normal builds  as well. =:^)
>

No, there can be no copy of sources for what I want. It just gets in the way having to do that.
Hacks like this seems to work:

post_src_compile() {
        # make it compile every time
        rm -f ${PORTAGE_BUILDDIR}/.compiled
}

post_src_install() {
        # make it install every time
        rm -f ${PORTAGE_BUILDDIR}/.installed
}

#hmm, doesn't seem to be an post_package function
#post_package() {
#       rm -f ${PORTAGE_BUILDDIR}/.packaged
#}

src_unpack() {
        #dir need to exist
        mkdir -p ${S} || die
}
src_compile() {
        EBUILDDIR=$(dirname ${FILESDIR})
        MYTRUNK=${EBUILDDIR}/../../..
        # add sandbox exceptions
        addwrite ${MYTRUNK}
        
        cd ${MYTRUNK} || die
        cd "${PN}"
.....
}