Clarifications on the D-Bus specification

[Havoc Pennington]

In a quick look I don't see any limit in the libdbus source on
recursing into nested types. The limit is just on the "depth" of the
type signature, which does not reflect dynamic type recursion as
created by variants.

It could probably be fixed by tracking the recursion depth in the
iterators. But the API probably doesn't allow throwing an error from
the right functions. So it could be tricky.

Havoc