From: "Iñaki Baz Castillo" <ibc@...>
Date: 2008-03-16T11:42:52+09:00
Subject: Re: Looking for an appropiate parser generator

El Domingo, 16 de Marzo de 2008, Eleanor McHugh escribió:

> The SIP protocol is in principle simple enough

opss, sure it's not simple at all, a lot of amiguations, each header has its 
own format, lots of extensions in lot of RFC's.... buff... simple?


> that you could probably 
> get by rolling your own custom parser by hand. 
It's what I'm doing for now but maybe it's better using an existing one. No 
idea.


> My colleague 
> implemented a console-driven SIP stack this way and whilst the code is
> inefficient compared to a table-driven parser it's eminently more
> readable.
>
> However if you do want to go down the parser-generator route for
> performance reasons then look at the Ragel parser in Mongrel as that's
> very efficient and highly conformant with the HTTP RFC specs (given
> some of the boundary cases in SIP conformance is probably high on your
> list of priorities). As far as I'm aware Ragel produces parsers in C,
> but the Mongrel code will show you how to turn that into a Ruby native
> extension.

AFAIK Ragel can write to Ruby since verison 6.0:
  http://www.devchix.com/2008/01/13/a-hello-world-for-ruby-on-ragel-60



Thanks a lot, I'll try Ragel.


-- 
Iñaki Baz Castillo