Re: [gentoo-dev] Re: News item review: SquashDelta syncing support

[Brian Dolbec]

On Mon, 18 May 2015 05:48:59 +0000 (UTC)
Martin Vaeth <martin@×××××.de> wrote:

> Rich Freeman <rich0@g.o> wrote:
> > Downsides include:
> > 2.  Impossible to tweak ebuilds without setting up an overlay.  This
> > might be annoying for devs/etc.
>
> It is still possible to setup a read-writable portage tree
> (using overlayfs/aufs/unionfs-fuse/... e.g. using the squashmount
> tool from the mv overlay).
>
> However, currently this does not play nicely with squashdelta:
> You have to "undo" the mounting of squashdelta and have to use
> different command (e.g. squashmount) afterwards.
> Although this can probably be done e.g. in eix-sync with hooks,
> I hope that in the near future there will be a possibility to
> combine these methods more conveniently.
>
> Currently, I made only some remarks in comment #3 of bug 549716,
> because it seems that the sync module mechanism is currently
> lacking the infrastructure for adding custom data (like hooks) to
> a module.
>
>

No, that is not correct, the new sync system also introduced a new
native portage postsync hook system.

1) /etc/portage/postsync.d/...  runs each script once at the completion
of all repos that were synced. (no arguments passed in)

2) /etc/portage/repo.postsync.d  runs each script at the end of each
repo that is synced.  Each script can determine if it needs to run or
simply exit.  Each script is called with 3 arguments  the repo name,
the url link it was synced to and the path to the repo.

Using that information you could easily add a postsync hook there
looking for the gentoo repo argument. And if not exit.  If it is the
gentoo repo, call your squashmount script to remount it your way.

See the example script in that directory.

-- 
Brian Dolbec <dolsen>