[syslog-ng]PTR lookups; leak/crash fixes

[Balazs Scheidler]

Hi,

> Why does syslog-ng do a PTR lookup for EVERY message?

Just as you describe below, I think caching DNS results belongs to libc. 

syslog-ng rewrites hostnames by default, and for this it needs a DNS lookup.
You have several options:

1) disable hostname rewriting by using the keep_hostname(yes) option
2) disable dns usage by use_dns(no)
3) do not accept remote messages :)

Installing nscd and a caching bind seems to be a good solution.

> If I were to set use_dns to `no' this would probably make the problem go
> away.  Is there any reason not to do this? Would I then get IPs for
> $HOST instead of names?

yes

> Incidentally, the assert fix definitely got rid of the crashing, and the
> string free definitely fixed some memory leakage.  But I have only been
> running it for one day and it's up to 6 meg VSZ so far (would have been
> 30 by now before the fix) ...hopefully this is just some data structures
> which will plateau out once it's been running for some time (xinetd does
> this in a big way ;)

-- 
Bazsi
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