Wireshark-dev: Re: [Wireshark-dev] RFD: New language to write dissectors

From: Guy Harris <guy@xxxxxxxxxxxx>
Date: Sun, 15 Jul 2012 03:24:37 -0700
On Jul 15, 2012, at 1:24 AM, Jakub Zawadzki wrote:

> On Sat, Jul 14, 2012 at 03:31:06PM -0700, Guy Harris wrote:
> 
>> 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.

Presumably by "one" you're referring to the choice between NPL and wsgd, given that we already *have* translators to take ASN.1, PIDL, CORBA IDL, and xcb and turn them into C dissectors.

> 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 who are using processors not supported as LLVM targets:

	http://www.llvm.org/docs/CodeGenerator.html

> ... Or can LLVM libraries be strong dependency?

Not unless we drop support for OSes and instruction sets not currently supported by LLVM.