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Date: Sun, 1 May 2011 12:26:52 -0500 (CDT)
From: Bob Friesenhahn <bfriesen@simple.dallas.tx.us>
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To: Rick Macklem <rmacklem@uoguelph.ca>
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Cc: rmacklem@freebsd.org, fs@freebsd.org
Subject: Re: newnfs client and statfs
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On Sun, 1 May 2011, Rick Macklem wrote:
>
> Or should I try and do the division to see if the large
> value in sf_abytes will fit in INT64_MAX after the division? Something
> like:
>  int64_t tmp;
>
>  tmp = sfp->sf_abytes;
>  tmp /= NFS_FABLKSIZE;
>  if (tmp < 0)
>     sbp->f_bavail = INT64_MAX;
>  else
>     sbp->f_bavail = tmp;

That one seems better because it preserves more of the value, but 
perhaps this is better because it does not depend on 
undocumented/undefined behavior (also untested):

   uint64_t tmp;
   tmp = sfp->sf_abytes / NFS_FABLKSIZE;
   if (tmp > (uint64_t) INT64_MAX)
     sbp->f_bavail = INT64_MAX;
   else
     sbp->f_bavail = tmp;

Bob
-- 
Bob Friesenhahn
bfriesen@simple.dallas.tx.us, http://www.simplesystems.org/users/bfriesen/
GraphicsMagick Maintainer,    http://www.GraphicsMagick.org/