On Sat, Feb 24, 2007 at 11:04:27AM -0500, John Jamulla wrote:
> I have some data in my own protocol that is really a set of 512, 2
> byte bit fields, and I want to display something like:
>
> Generator 1 Fielda
> Generator 1 Fieldb
> Generator 1 Fieldc
> Generator 1 Fieldd
> Generator 2 Fielda
> Generator 2 Fieldb
> Generator 2 Fieldc
> Generator 2 Fieldd
> ...
>
> Where field a-d are bitfields. I know how to get the bits into a
> useful value, but I have no idea really how to display something like
> this?
You would typically use proto_tree_add_item() and define the bitmask as
part of the hf[] field registration. Search doc/README.developer for
bitfield for some more information. You can also take a look at an
existing dissector to see how it is handled. The VNC dissector
(epan/dissectors/packet-vnc.c) uses bitfields in a number of places, for
example:
proto_tree_add_item(subrect_tree, hf_vnc_hextile_subrect_x_pos, tvb,
*offset, 1, FALSE);
{ &hf_vnc_hextile_subrect_x_pos,
{ "X position", "vnc.hextile_subrect_x_pos",
FT_UINT8, BASE_DEC, NULL, 0xF0, /* Top 4 bits */
"X position of this subrectangle", HFILL }
},
Does this help?
Steve
