Wireshark-dev: Re: [Wireshark-dev] one possible way to speed up filtering

From: didier <dgautheron@xxxxxxxx>
Date: Sun, 22 Mar 2009 22:24:55 +0100
Hi,
Le dimanche 22 mars 2009 ᅵ 02:13 +0800, yami a ᅵcrit :
> Hi Didier,
> 
> Thank you for trying the patch :) and all the good comments given. 
> 
> I've attached a new patch to the wiki. Please see my detailed reply
> below.
>         
>         - If compiled without NDEBUG defined I get a failed assert:
>         epan/dfilter/wslimmat.c :1680 : fix_variables:  "v->assignment
>         == v"
> It seems like a 'bug' of gcc optimization. We can simply remove this
> assertion, see explanations below.
Possible but unlikely.
I'm not 100% sure, but for me fix_pointer() needs -fno-strict-aliasing.

> Really? I've thought BSD license is looser than GPL (can you give me
> more details?).
http://www.gnu.org/licenses/license-list.html#GPLIncompatibleLicenses
search for Original BSD license

>  
> On the other hand, I find Wireshark code has already contains similar
> licenses (am I right?), for example,
> Menu -> Help -> About Wireshark -> License -> Part III has metioned
> some.
Yes but only two and three clauses BSD, not the original.

> However using a SAT solver (even if it is a simple one) is the most
> generalized way, which requires no special handling. And it is also a
> good example of how math is applied in real life :)
I'll try to merge it with
http://wiki.wireshark.org/Development/Optimization , this version is
already able to find 2000 DNS packets inside 7 millions packets in 1
second.

> 
> Cons are
> 1. SAT solvers are complicated. (But we may use a simple algorithm)
> 2. Public available SAT solvers are mainly wrote by researchers, which may not have time to maintain the software.
> 
Didier