Dreamhack changes

[solariz]

We succesfully used it at the Dreamhack DE, this is my commit some minutes before our dismantling starts :)
Added several games and added statistic log function to the code. This stat file was pushed to a influxDB so we directly could get some very interesting insights of what was received and forwarded exactly. SDH works pretty well, just had a few problems.

[solariz]

With disabled optimization I receive a mem alloc error if using a certain amount of ports.

Opening PCAP interface for eth1.110
Warning: Kernel filter failed: Cannot allocate memory
Error setting filterCouldn't create a listener for all interfaces. Exiting.

Enabled pcap filter optimiization and everything is fine.

[solariz]

Got a strange behavior here, sometimes on a debian machine pcap did not return -1 as required

[sirsquidness]

I think this is missing the value being update after each loop (eg, logtimer = time(NULL)), so this will run every time a packet is forwarded?

[solariz]

Actually it is missing but somehow it run correctly :) Will check.

[sirsquidness]

Does your use case with influxDB support single line entries? I'd prefer single line entries (eg, CSV, JSON, or similar) so that it's more of a traditional log, but I don't mind leaving this as is if you can't use single line :)

[solariz]

I choose this way of logfile because it'S still human readable. For pushing it to influxDB I used a sperate bash Script to convert this into a one line insert every 10s.

[solariz]

I put the Bash Script I'm using to pusinh this stats into a influxDB at gist:
https://gist.github.com/solariz/29362abbcf45605ab700df6f6e6be141

It's pretty simple, influx can handle a huge amount of posts per second so we're totally fine with that currently. On the last event the influx run on a raspberry pi at a mean CPU cycle of less then 10% :)

[sirsquidness]

How many packets did you see at your event? Did an int32 get close to overflowing? Probably better to make it an int64 just in case?

[sirsquidness]

Ditto for this - I expect the short would overflow pretty regularly? Maybe in the future we should make this a hash table so we don't need a giant array of mostly 0s, or somehow index the array based on the ports listed in the ports file. Not important though, just thinking out loud

[solariz]

Hey, indeed on the event the counter overflow several times, especially 27015 :)
For my purpose it was ok because I just tracked difference between previeous poll in a 10s resolution. But could be changed to int64

[sirsquidness]

Thank you so much for submitting this PR! It's so exciting to know that Dreamhack used something I wrote :D

I am happy to merge this PR as is, but I left a few comments to get your thoughts.

And thanks especially for the BPF optimisation thing - I had that problem last time I used it, and worked around by running multiple instances of the app. This is a much nicer solution :)

[mintopia]

We've been using it at epic.LAN for over a year now as well. Thanks adding the extra games to it as well. I'm looking forward to getting some stats from our next event!

[solariz]

Hey, pushed back latest fixes. Guess I'm out for now until next LAN :)

Ready for Merge 👍

[sirsquidness]

Merged! Thanks again, both for finding the tool useful and for contributing back :)