Re: [gentoo-embedded] quickpkg and PKG_INSTALL_MASK

[Joakim Tjernlund]

solar <solar@g.o> wrote on 2011/12/25 18:52:52:
>
> On Sun, 2011-12-25 at 11:34 +0200, Kfir Lavi wrote:
> >
> >
> > On Fri, Dec 23, 2011 at 3:23 PM, Joakim Tjernlund
> > <joakim.tjernlund@×××××××××.se> wrote:
> >
> >         I got the impression from docs that PKG_INSTALL_MASK would
> >         actually
> >         mask files out so they never get into the binary package, this
> >         doesn't
> >         seem to happen.
> >         Did I misunderstand? If I did, I think an MASK to do the above
> >         would be a worthy addition to quickpkg, very useful for
> >         embedded targets to keep the pkg size down.
> >         Also PKG_INSTALL_KEEP which would list files keep(rest is
> >         dropped) would be nice.
> >
> >         Oh, something else I wonder about. How does pre/post install
> >         work with
> >         quickpkgs? Is it possible to have such scripts and then have
> >         qmerge execute
> >         them?
> >
> >         Jocke
> >
> >
> > Yes, PKG_INSTALL_MASK on time of installation will mask the files
> > defined in it.
> > Binary package do contain all files, even the masked files.
> > Kfir
>
>
> $PKG_INSTALL_MASK is supposed to omit the files in it's list from making
> it into the binary pkgs in the first place. The idea there was to make
> smaller binary pkgs for embedded devices and such (for use only with
> private repos).
>
> $INSTALL_MASK is supposed to omit the files listed in it from being
> installed on the file system.

Hi Solar, long time no see :)

So the current behaviour is a bug, good to know.

I am contemplating a greater problem too. Our system require we can install
multiple versions of our SW and switch between them. This is easy to do when it
comes to our own app but not when one want to upgrade core parts of the system, like
libc etc.

So I am thinking one could use --bind mounts and switch_root to solve that. Basically
one has a skeleton root FS with /bin, /lib, /usr /opt etc.
Each upgrade goes into dirs like:
  bin_1.x.y/ usr_1.x.y/ lib_1.x.y/ opt_1.x.y/ sbin_1.x.y/
Then, from an initramfs, one selects which of xxx_1.x.y dir one wants to use
and --bind mounts them under the corresponding skeleton dir.

To do that one needs an way to repackage a root fs created by a bunch of different
ebuilds, some of them spanning several of the above dirs, into a package per xx_1.x.y dir.
Not sure if this can be done with the current portage/portage-utils and how, any
ideas welcome :)

Perhaps there is a better way then the above?

 Jocke