Re: ncat --max-conns

[Solar Designer <solar () openwall com>]

This is a correction to my own posting from a couple of days ago.  The
"alternative" get_conn_count() function below:

On Tue, Oct 06, 2009 at 02:52:00AM +0400, Solar Designer wrote:
> Alternatively:
>
> static int get_conn_count(void)
> {
>       unsigned int conn_count;
>       do {
>               conn_dec_changed = 0;
>               conn_count = conn_inc - conn_dec;
>               if (conn_inc < conn_dec && !conn_dec_changed);
>                       return -1; // error, counts got out of sync
>       } while (conn_dec_changed);
>       return conn_count;
> }

is not correct in that it "forgets" about the wraparounds of conn_inc
and conn_dec possibly being legitimate (for a long-living process) as
it was suggested earlier in that posting.  The first version of
get_conn_count() given in the posting (with the check against INT_MAX)
is wraparound-compatible, and thus it should be preferred.  INT_MAX may
be replaced with some smaller number (if another upper limit is known).

Alexander

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