[Buildd-tools-devel] Reorganising schroot classes

[Jan-Marek Glogowski]

Hi

Probably you have read about the fs-union patch I have submitted to this
list eralier this week.

After implementing the union stuff as a seperate schroot type, and some
discussion on the list, I came to the conclution, that a fs union is a
more general feature, the just an other schroot. The idea was to move the
feature into source_chroot.

But I came up with a new structure: just distinguish between chroot-source
and session actions.

Four chroot-source types:
  chroot
  |-- dir -- file
  |-- block device -- lvm

A has to "functions": start real session, start source session

Session actions can be:
  session
  |-- copy -- unpack
  |-- lvmsnap
  |-- fs union
  |-- cd
  |-- mount
  |-- bind
  |-- repack

Now we assign list of session types to start a session:

src     | real session  | source session

dir     | copy or union | cd
file    | unpack + dir^ | unpack + dir^
block   | mount + union | mount
lvm     | lvmsnap       | mount

I have not yet looked into the code doing all bind mount. And For file you
would need to pack the dir of the source session.

Comments welcome

Jan-Marek