[nos-bbs] Update - Timer issues in JNOS

Maiko Langelaar maiko at pcs.mb.ca
Tue Aug 3 13:45:33 EDT 2010

Good day,

The msclock() function returns a signed integer, which we know to
have an upper limit of 2 147 483 647. With some debugging info, and
some calculations, it would appear that msclock() will return a value
of 2 178 000 000 after roughly 25 days - exceeding the upper limit.

In unix.c - ding() - calculation of clock results in this :

    24 days - clock 38016000
    25 days - clock -38490314

If an unsigned integer was used instead, we would see this instead :

    24 days - clock 38016000
    25 days - clock 39600000

Unfortunately msclock() returning a signed integer also affects a
few other areas of JNOS for linux - things like the 'rtt' value used
in tcp, ip, and ax25 traffic, timeouts in the ftp client, dns queries,
and hop checks. So it's not just a matter of redefining msclock() to
return an unsigned integer.

To be honest with you, I'm not so sure I like the way the whole clock
thing is done to begin with - seems like alot of work just so that we
can keep track of when JNOS was first started ? Might change this ...

Anyways, it's clear what is going on here. I'll have a fix out shortly.

Maiko Langelaar / VE4KLM

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