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From: "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>
Subject: Re: AI12-0218: What is the portable representation clause for processing IETF packets on little-endian machines?
Date: Thu, 10 May 2018 21:34:35 +0200
Date: 2018-05-10T21:34:35+02:00	[thread overview]
Message-ID: <pd26sb$ik6$1@gioia.aioe.org> (raw)
In-Reply-To: ec0145a4-9698-41f2-bc70-964dc1850e50@googlegroups.com

On 2018-05-10 19:45, Dan'l Miller wrote:
> It seems that 2 major use-cases of AI12-0218 are getting short shrift.
> 
> http://www.ada-auth.org/cgi-bin/cvsweb.cgi/ai12s/ai12-0218-1.txt?rev=1.3&raw=N
[...]
> The Challenge:
> Without the proposed solution in AI12-0218, I challenge anyone to write an Ada representation clause that is •portable• to both little-endian and big-endian processors for either of the following IETF packet formats that must always be in big-endian network byte order:
> https://en.wikipedia.org/wiki/IPv4#Packet_structure
> https://en.wikipedia.org/wiki/IPv6_packet

Representation clauses are useless for network protocols and 
serialization, for multiple reasons. I never used them in any of the 
protocol implementations I wrote.

The only place representation clauses could have is mapping special 
machine registers, which naturally excludes any questions of portability.

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de


  parent reply	other threads:[~2018-05-10 19:34 UTC|newest]

Thread overview: 63+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-05-10 17:45 AI12-0218: What is the portable representation clause for processing IETF packets on little-endian machines? Dan'l Miller
2018-05-10 19:24 ` Dan'l Miller
2018-05-10 20:32   ` Paul Rubin
2018-05-10 22:24     ` Dan'l Miller
2018-05-10 22:44       ` Niklas Holsti
2018-05-10 23:14         ` Paul Rubin
2018-05-11  2:38         ` Dan'l Miller
2018-05-11  7:55           ` Simon Wright
2018-05-11 12:11             ` Lucretia
2018-05-11 13:49               ` Simon Wright
2018-05-11 16:11                 ` Jeffrey R. Carter
2018-05-11 16:48                   ` Simon Wright
2018-05-11 19:08                     ` Jeffrey R. Carter
2018-05-11 21:39                       ` Simon Wright
2018-05-11 21:56                         ` Jeffrey R. Carter
2018-05-12  7:08                           ` Simon Wright
2018-05-12  7:53                             ` Jeffrey R. Carter
2018-05-14 22:43                             ` Randy Brukardt
2018-05-11 13:46             ` Simon Wright
2018-05-11 22:12           ` Randy Brukardt
2018-05-12 10:33             ` Björn Lundin
2018-05-12 13:08               ` Simon Wright
2018-05-12 14:21                 ` Björn Lundin
2018-05-10 23:07       ` Paul Rubin
2018-05-11  0:14         ` Dan'l Miller
2018-05-11  0:30           ` Paul Rubin
2018-05-11  0:50             ` Dan'l Miller
2018-05-11  1:34               ` Paul Rubin
2018-05-11  2:11                 ` Dan'l Miller
2018-05-11 22:32                   ` Randy Brukardt
2018-05-11  8:02         ` Simon Wright
2018-05-11 22:14         ` Randy Brukardt
2018-05-10 19:28 ` Simon Wright
2018-05-10 22:40   ` Randy Brukardt
2018-05-10 22:50     ` Dan'l Miller
2018-05-11 22:00       ` Randy Brukardt
2018-05-12  1:15         ` Paul Rubin
2018-05-14 22:54           ` Randy Brukardt
2018-05-15  0:43             ` Paul Rubin
2018-05-15 21:39               ` Randy Brukardt
2018-05-15  0:44             ` Dennis Lee Bieber
2018-05-11  8:09     ` Simon Wright
2018-05-10 19:34 ` Dmitry A. Kazakov [this message]
2018-05-10 20:06   ` Dan'l Miller
2018-05-10 22:44     ` Paul Rubin
2018-05-10 22:50     ` Randy Brukardt
2018-05-11  9:40       ` Niklas Holsti
2018-05-11 11:40         ` Dan'l Miller
2018-05-11 20:16           ` Niklas Holsti
2018-05-11  9:40     ` Dmitry A. Kazakov
2018-05-11 14:21 ` AdaMagica
2018-05-26 16:15 ` Dan'l Miller
2018-05-26 19:02   ` AdaMagica
2018-05-26 21:01     ` Dan'l Miller
2018-05-27 14:58       ` AdaMagica
2018-05-27 18:03         ` Simon Wright
2018-05-29 22:17           ` Randy Brukardt
2018-05-30  6:39             ` Simon Wright
2018-05-30  7:25               ` Dmitry A. Kazakov
2018-05-30 15:01                 ` Simon Wright
2018-05-30 15:59                   ` Dan'l Miller
2018-05-30 19:38               ` Randy Brukardt
2018-05-27 18:04         ` Dan'l Miller
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