From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me X-Spam-Level: X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00 autolearn=unavailable autolearn_force=no version=3.4.4 X-Received: by 2002:a6b:88cb:: with SMTP id s72-v6mr1418733ioi.117.1525982813710; Thu, 10 May 2018 13:06:53 -0700 (PDT) X-Received: by 2002:a9d:5a0a:: with SMTP id v10-v6mr132468oth.13.1525982813429; Thu, 10 May 2018 13:06:53 -0700 (PDT) Path: eternal-september.org!reader01.eternal-september.org!reader02.eternal-september.org!feeder.eternal-september.org!paganini.bofh.team!weretis.net!feeder6.news.weretis.net!feeder.usenetexpress.com!feeder-in1.iad1.usenetexpress.com!border1.nntp.dca1.giganews.com!nntp.giganews.com!v8-v6no659777itc.0!news-out.google.com!f20-v6ni807itd.0!nntp.google.com!u74-v6no668432itb.0!postnews.google.com!glegroupsg2000goo.googlegroups.com!not-for-mail Newsgroups: comp.lang.ada Date: Thu, 10 May 2018 13:06:53 -0700 (PDT) In-Reply-To: Complaints-To: groups-abuse@google.com Injection-Info: glegroupsg2000goo.googlegroups.com; posting-host=47.185.233.194; posting-account=zwxLlwoAAAChLBU7oraRzNDnqQYkYbpo NNTP-Posting-Host: 47.185.233.194 References: User-Agent: G2/1.0 MIME-Version: 1.0 Message-ID: <2821b8e0-2c64-4621-b65e-337027fc121e@googlegroups.com> Subject: Re: AI12-0218: What is the portable representation clause for processing IETF packets on little-endian machines? From: "Dan'l Miller" Injection-Date: Thu, 10 May 2018 20:06:53 +0000 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Xref: reader02.eternal-september.org comp.lang.ada:52210 Date: 2018-05-10T13:06:53-07:00 List-Id: On Thursday, May 10, 2018 at 2:34:39 PM UTC-5, Dmitry A. Kazakov wrote: > Representation clauses are useless for network protocols and=20 > serialization Serialization? LoL!! Streamed field-by-field (even textual?) serializatio= n like OO designs do? Hahahaha. That is not even on-topic at all regardin= g fixed-header binary packet layouts in this thread. When the Dmitry Engin= eering Task Force (DETF) designs the Dmitrynet protocol stack to replace th= e Internet protocol stack at & near layer 3, you can rework all of IETF's f= ixed packet-header binary layouts to be your =E2=80=98serialization=E2=80= =99. But until then, we're not tilting at windmills; we live in IETF's rea= lity of their packet-header formats. Now show how to process them portably= in Ada without AI12-0218. >, for multiple reasons. I never used them in any of the=20 > protocol implementations I wrote. LoL!! Oh, do tell why a representation clause on an IETF packet's header l= ayout is =E2=80=9Cuseless=E2=80=9D. (For decades and decades, IETF intenti= onally designs its packet headers to be typecasted as meticulously-laid-out= C structs.) > The only place representation clauses could have is mapping special=20 > machine registers, which naturally excludes any questions of portability. LoL!! Oh, so an IC manufacturer doesn't want to sell their chips to both b= ig-endian and little-endian accounts? Or is it that the IC manufacturer wa= nts to write entirely different source code for different processors? Or i= s it that the IC manufacturer never provides the source code to a reference= -implementation device driver to their customers at all? Job security by e= limination of all portability of software; write a fresh variant for every = target, even if they differ only slightly.