We aren't taking full advantage of seedcache and untarring things isn't
a big burden on us anyway so don't bother and hopefully avoid leaving
oodles of files behind.
A few things here:
- Source manifests/version.txt directly instead of coreos-version.sh
- Remove Chrome branch from target image directory names.
- Use proper version instead of timestap for catalyst builds.
- Move lsb_release script from coreos-overlay to build_library.
When running bootstrap_sdk for the first time on a host the default of
using a previous catalyst run as a seed won't work but this may be a
fresh SDK install so that tarball is probably around somewhere and will
work as a default seed for most things.
This uses Gentoo's catalyst for very thoroughly building images from
scratch. Using images based on this will eliminate some of the hackery
in make_chroot.sh for building up the sdk from a stock stage3 tarball.
For reference the procedure it performs is this:
1. snapshot: Grab a snapshot of portage-stable. Note that overalys are
not snapshotted.
2. stage1: Using a "seed" tarball as a build environment, build a
minimal root file system into a clean directory using ROOT=...
and USE=-* The restricted USE flags are key be small and avoid
circular dependencies.
3. stage2: Run portage-stable/scripts/bootstrap.sh
This rebuilds the toolchain. Probably not strictly necessary most of
the time but does super-duper-promise that the toolchain isn't linked
to or otherwise influenced by whatever was in the "seed" tarball.
4. stage3: Run emerge -e system to rebuild everything using the fresh
toolchain using the normal USE flags provided by the profile. This
will also pull in assorted base system packages that weren't included
in the minimal environment stage1 created.
5. stage4: Install any extra packages or other desired tweaks. For the
sdk we just install all the packages normally make_chroot.sh does.
