Wireshark · Wireshark-dev: Re: [Wireshark-dev] Wireshark lua (wslua) and bit fields - how to do it?

[Tamás Regõs <Tamas.Regos@xxxxxxxxxxxx>]

Hi,

 

Try ByteArray.tvb(hexba,"hex") instead of Tvb.new_real(hexba, "hex")
Tvb.new_real does not exists.

 

Regards,

Tamas

 

---

From: wireshark-dev-bounces@xxxxxxxxxxxxx [mailto:wireshark-dev-bounces@xxxxxxxxxxxxx] On Behalf Of Daniel Lynes
Sent: Friday, 22 October 2010 4:46 AM
To: wireshark-dev@xxxxxxxxxxxxx
Subject: [Wireshark-dev] Wireshark lua (wslua) and bit fields - how to do it?

I'm trying to output some bit values in my wireshark dissector 
decode.  However, I want to be able to filter based on those bit 
values.

I can't seem to use the LUA bitop library to do it, because lua 
complains that the result is not a uservalue.

I've got the following 
code:

                        
for shred = 1, 
num_shreds
                        
do
                                
subtree:add("----- NV Storage Shred " .. shred .. " 
-----")
                                
subtree:add(fields.shred_id, buffer(offset, 
8))
                                
subtree:add(fields.shred_flags, buffer(offset+8, 
8))
                                
local 
flags=tonumber(tostring(buffer(offset+8,8):uint64()))
                                
local 
hex=tostring(bit.tohex(bit.band(flags,0x02)))
                                
subtree:add("----- NV Storage hex flags: " .. 
hex)
                                
local 
hexba=ByteArray.new(hex)
                          
-- The following line complains about a nil 
uservalue
                                
local rdonly=Tvb.new_real(hexba, 
"hex")
                          
-- The following line complains about the value being a number instead of a 
uservalue
                                
subtree:add(fields.shred_rd, bit.band(flags, 
0x02))
                                
offset=offset+inc
                        
end

Does anyone happen to have any clues as to what I'm doing 
wrong?  Fwiw, I'm using 1.2.0 (1.3, 1.4, and 1.5 all have video corruption 
issues, and 1.0 has issues with 64-bit integers).

Thanks.