[Box Backup] Irregular Expressions

Reinhard Tartler boxbackup@fluffy.co.uk
Mon, 24 Sep 2007 10:01:13 +0200


Chris Wilson <chris@qwirx.com> writes:

> Ben rightly pointed out that my assumptions Box Backup's support for
> regular expressions were wrong. The current state is that we use POSIX
> regular expressions where available (all POSIX Unix platforms) and
> Perl-compatible regular expressions through PCRE on Windows.
>
> [ ... ]
>
> There are several options for how to fix this, none of them ideal, and I
> wanted to see what opinions people (users, developers and packagers) had
> about them.
>
> 1. Do nothing. The worst option (in my view) except that it takes no time.
>
> 2. Use PCRE everywhere and add it as a dependency. People with platforms
> with no native PCRE package, and embedded system developers, might hate
> us for this (Solaris? AIX?) but you could still build Box with no
> regular expression support at all.


Please consider upgrade paths. Will have Linux-Users currently using Posix
regex in their boxbackup config have to adapt their config files on
upgrades? If the upgrade is not handled carefully, users risk breaking
their boxbackup configuration.

There are of course several ways of implementing the upgrade issue, like
checking for an 'incompatible' regex string and screem, or supporing
both regex styles and expanding the configuration syntax. I don't have a
particular preference (other that I prefer PCRE over posix regex), but
please consider an upgrade path.

-- 
Gruesse/greetings,
Reinhard Tartler, KeyID 945348A4