[Nbd] Back to the options parsing debate

[Alex Bligh <alex@...872...>]

It occurred to me that we are reinventing the wheel with this a bit. Parsing
options and lengths and so forth is error-prone, and is likely to result in
interoperability difficulties.

Extensible languages for describing options already exist. For a local
hack here, I thought about passing the disk name an XML blob - this
would allow me to pass the disk name and all sorts of other options
right from the client without any new client-side coding. It then
occurred to me that if the client passed what it wanted in an XML
blob (including the disk name), perhaps with the server sending some
XML at some stage too, perhaps this would be an easy way out of
the extensibility issue.

libxml is pretty easy to use, and as the xml goes through only at
mount time, it's hardly speed critical.

Just a thought.

--
Alex Bligh