Wireshark-users: Re: [Wireshark-users] Debugging Wireshark dissector plugins
From: Stephen Fisher <steve@xxxxxxxxxxxxxxxxxx>
Date: Tue, 12 Jan 2010 12:12:35 -0700
On Jan 12, 2010, at 11:52 AM, sean bzd wrote:

> I asked a similar question before but got no response. Can someone please provide some direction?

You should probably ask this on wireshark-dev@xxxxxxxxxxxxx (after subscribing to that list) as that is for development issues.  A lot of the same folks hang out on both of these lists though.

> Problem:
> I have a custom dissector and works fine most of the time; but sometimes, when I load the network capture containing packets (that the dissector is supposed to understand), the Wireshark application just hangs. The CPU consumption goes to 50% and stays there...it is as if it is in a tight loop. I'm using version 1.2.2 but same happens with different versions of wireshark; I know that the problem is in the dissector because if I remove the dissector plugin, wireshark is able to load the capture file. But i need some direction on how to proceed forward. Can i put some printfs in the dissector or elsewhere? Any other ideas?

Which operating system are you developing on?  The first thing I would try would be to run Wireshark in a debugger for your OS and break out of it when it seems to be stuck in a loop and look at the stack trace.  Unfortunately, no one has had a chance to add many details to the developer's guide on debugging (http://www.wireshark.org/docs/wsdg_html_chunked/ChSrcDebug.html), but we can probably help on the wireshark-dev mailing list once we know your operating system.


Steve