From mboxrd@z Thu Jan  1 00:00:00 1970
Message-ID: <ee9e417a050514091821ab55d5@mail.gmail.com>
Date: Sat, 14 May 2005 12:18:36 -0400
From: Russ Cox <russcox@gmail.com>
To: Fans of the OS Plan 9 from Bell Labs <9fans@cse.psu.edu>
Subject: Re: [9fans] silly dhcpd question
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	<14ec7b18050514014012d4e1fe@mail.gmail.com>
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You guys don't appear to be running the Plan 9 that I am.

1. As Boyd pointed out, the correct fix is to use lower case
in ndb.  Ndb is treating its entries as plain old case-sensitive
strings.  For the most part, the lookup routines have no
idea what an IP address or an ethernet address is, so when
dhcpd asks for an entry with ether=3D00d0c9670733 it doesn't
match against ether=3D00D0C9670733. =20

The correct fix, if there is one, is to change the ndb reading
routines to recognize certain attributes and canonicalize
them: ip, ether, dom, maybe sysname.  But then it will be
weird that dom is case-insensitive but bootf is not.  Should
fs be case-sensitive?  Etc.  I'm much happier requiring that
the ndb entries be stored in canonical form than doing magical
rewriting under the hood.=20

2. Parseether (which ndb isn't using) correctly handles upper
case ethernet addresses already. =20

3. Strtoul correctly handles upper case hex already, as required
by the C standard. =20

The program below prints

    abcdef
    abcdefabcdef

for me.

Russ

#include <u.h>
#include <libc.h>
#include <ip.h>

void
main(void)
{
=09uchar ea[6];

=09fmtinstall('H', encodefmt);
=09print("%x\n", strtoul("ABCDEF", 0, 16));
=09parseether(ea, "ABCDEFABCDEF");
=09print("%.6lH\n", ea);
}