Wireshark · Wireshark-dev: Re: [Wireshark-dev] Simplifying (and fixing) tvbuff [Long]

[Jaap Keuter <jaap.keuter@xxxxxxxxx>]

On 2011-12-14 15:02, Chris Maynard wrote:

> Bill Meier writes:
>
> > I think the long description boils down to the following: Consider 
> > the
> > collection of tvbs (chain) as a stack of tvbs. packet.c pushes the
> > initial tvb onto the stack then calls next dissector; After the
> > dissection is complete, the stack is eventually free'd via a call to
> > tvb_free_chain in epan_dissect_cleanup. A dissector: - can add new
> > tvbs
> > (real, subset, composite) to the stack handed to it; (Subset and
> > Composite tvbs should reference only tvbs which are towards the
> > beginning of the same stack). - must not save a pointer to a tvb 
> > from
> > that stack (handed to it) for use when dissecting another frame 
> > (since
> > a higher level function may very well free the stack); - can create
> > its
> > own tvb stack which the dissector is free to manage as desired.
>
> Bill, this information, plus the recent post entitled, "buffer to 
> tvb",
> got me
> wondering if there is perhaps enough useful information here worthy 
> of a
> separate doc/README.tvbuff?
>
> - Chris

+1, documenting such fundamental building blocks is always good. 
Eventually
this would end up in section II of the developer guide.

Thanks,
Jaap