please test: Secure ports tree updating

[Colin Percival]

David Rhodus wrote:
> Is this something that can be used to replace cvsup in a general term
> like cvsync ?

In theory, maybe, but in practice, no.  Portsnap distributes snapshots
of the ports tree; it isn't designed for distributing the entire CVS
repository.  If you tried to use the portsnap build code for distributing
the ports repository, you'd find it to be impractically slow, since there
are some huge files (INDEX,v is 82.5MB) which would take far too long for
my binary diff code to handle.

When it comes to using portsnap for distributing snapshots of the src/,
doc/, or www/ trees, there are other problems.  First, these are branched,
which means that lots of different snapshots would need to be created;
also, while the ports tree is easily split into bite-sized pieces which
tend to change independently of each other (ie, individual ports -- usually
a single commit will touch several files, but only within a single port
directory), the other repositories don't divide so easily into independent
parts.

I'm glossing over a few details here, but basically: I've given this some
thought, and I think that while portsnap is useful for the ports tree, I
don't think it will be very useful for anything else.

Colin Percival