[SMB2] buffer handling

[tridge at samba.org]

Metze,

 > you may want to take a look at the attached patch.
 > I needed this to make the persistent handle domonstration patch.
 > 
 > This allows us to distinguish between a NULL buffer and a zero length
 > buffer. And it also handle padding of the buffers.
 > 
 > I'm not sure if it still applies cleanly, but you may get the idea.

Thanks. I think we can do this in a bit simpler way. This sort of
multiple blob stuff only seems to happen in create calls, so I think
having something for the server side that matches the
smb2_create_blob_add() client side code will work and will be a bit
less intrusive.

Cheers, Tridge