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From: sean@firefly.rain.com (Sean Sheedy)
Newsgroups: comp.mail.misc,comp.mail.uucp
Subject: Re: Pathalias creating recursive paths for site island and moon!!
Message-ID: <1991May22.203115.17990@firefly.rain.com>
Date: 22 May 91 20:31:15 GMT
References: <1991May21.204119.652@coplex.uucp>
Organization: Firefly Enterprises
Lines: 40

In article <1991May21.204119.652@coplex.uucp> dean@coplex.uucp (Dean Brooks) writes:
>   Here are a few of the sample entries:
>
>This is the the path it shows to uunet, to which we are directly connected!!
>
>uunet!dis!moon!island!uunet!moon!island!uunet!moon!island!uunet!moon!island!
>               uunet!moon!island!uunet!moon!island!uunet!moon!island!uunet!
>               moon!island!uunet
>
>[...]
> 
>Anyone else seen this?  Is this a problem with pathalias, or is it a
>problem with a vertain map entry?

Yes, I've seen it and (partially) tracked down the problem.  The following
lines are in mapit.c:

        if (DEADLINK(l))
                cost += INF;                             /* dead link */
        if (DEADHOST(prev))
                cost += INF;                             /* dead parent */
        if (GATEWAYED(next) && !(l->l_flag & LGATEWAY))
                cost += INF;                             /* not gateway */
        if (!ISANET(prev)) {
                if ((NETDIR(l) == LLEFT && (prev->n_flag & HASRIGHT))
                 || (NETDIR(l) == LRIGHT && (prev->n_flag & HASLEFT)))
                        cost += INF;                     /* mixed syntax */
        }

where INF is 100 million.  Something about the most recent set of maps causes
this code to be executed a lot for some paths, causing cost to wrap around
to a negative number.  Strange results then occur.  Changing "+=" to "="
seems to fix the problem and give reasonable paths.

Sean

-- 
Sean Sheedy					sean@firefly.rain.com

Every decent man is ashamed of the government he lives under.	-- H.L. Mencken