Hmm, What about implementing a compiler that generates C dissector source code, from NPLt m, or WSGD dissector code? Or would that be overkill for what we're trying to do?
Just my 0.02p... Tyson. 2012/7/15 Jakub Zawadzki <[email protected]> > On Sat, Jul 14, 2012 at 03:31:06PM -0700, Guy Harris wrote: > > > > On Jul 14, 2012, at 8:26 AM, Jakub Zawadzki wrote: > > > > > It'd be great if we have some abstract and pure (no C/assembly inline) > language to write dissectors. > > > > Or "to describe protocols and the way packets for those protocols are > displayed" - the languages in question wouldn't be as procedural as > C/Lua/etc, they'd be more descriptive. > > > > > We could invent yet another protocol desciption language, > > > > ...but, as you suggest, we probably shouldn't. > > http://imgs.xkcd.com/comics/standards.png ;-) > > > I'm not sure it has to be a choice, though - we could implement both, > resources permitting, of course. (And, of course, given that there are > many already-existing languages that describe protocols - ASN.1, {OSF > IDL/MIDL/PIDL} for DCE RPC, rpcgen for ONC RPC, CORBA IDL, xcb for X11 - we > will probably never have the One True Protocol Description Language.) > > I'd rather support one, and later have some compiler from language A to B. > > > > > I'm bigger fan of NPL (...) but there might exists some legal (patents > for grammar/implementation?!) issues. > > > > That would be one concern - even having "our own" language, such as > wsgd, runs the risk of infringing a patent, but, well, *writing software of > just about any sort* runs the risk of infringing a patent; > > however, we're dealing with a large corporation in the case of NPL, so > there's probably a greater risk that some or all of it is covered by > patents. > > Were Microsoft to explicitly state that there are no patents on > NPL-the-language or that they're granting a royalty-free license for all > implementations (perhaps with a "mutual assured destruction" clause, > > so that were we to patent some feature of Wireshark and sue Microsoft > for violating that patent, our license for their patents would terminate), > and the same applied to any patents they hold on their > > implementation of NPL that would block independent useful > implementations, that might help. > > I'm not sure if it was covered by recent Oracle vs Google lawsuits. > Maybe Riverbed could help us with it? Gerald? > > > > With wsgd we could reuse some existing code of plugin. > > > > ...and we also have more freedom to extend the language, e.g. to support > preferences for a protocol > > or support for columns/expert info. > > > Were there an "Open NPL Consortium" of some sort where multiple > implementers of NPL could propose extensions, and perhaps a way an > implementation could offer private extensions without worrying about > colliding with other implementations or future standards, that might help. > > It'd also clear legal status of NPL language. > > > > (It also raises the question of whether interpreted execution of that > "machine code" or translation to C or machine language will be faster - > interpreted execution *could* result in a smaller cache footprint if the > interpreter is small enough and the code "high-level" enough to be fairly > dense, although it does involve difficult-at-best-to-predict branches in > the interpretive loop.) > > I was thinking to use LLVM. For built-in dissectors we could compile > dissectors to object file/ assembly, for user dissectors we'll benefit from > LLVM JIT. > But anyway we need compiler to C. For prototype (does it work?) and later > as fallback for people who don't have LLVM. > ... Or can LLVM libraries be strong dependency? > ___________________________________________________________________________ > Sent via: Wireshark-dev mailing list <[email protected]> > Archives: http://www.wireshark.org/lists/wireshark-dev > Unsubscribe: https://wireshark.org/mailman/options/wireshark-dev > mailto:[email protected] > ?subject=unsubscribe > -- Fight Internet Censorship! http://www.eff.org http://vmlemon.wordpress.com | Twitter/FriendFeed/Skype: vmlemon | 00447934365844
___________________________________________________________________________ Sent via: Wireshark-dev mailing list <[email protected]> Archives: http://www.wireshark.org/lists/wireshark-dev Unsubscribe: https://wireshark.org/mailman/options/wireshark-dev mailto:[email protected]?subject=unsubscribe
