These diagnostics are supposed to guide the user to problem resolution.
They're displayed if no packet is received from the server within one
second of connecting.
No message if we don't have STUN servers.
"Trying to determine UDP connectivity..." if no answer has been received
from the STUN server yet and it hasn't timed out yet.
"UDP seems to be filtered." if the STUN request has timed out.
"UDP and TCP IP addresses seem to be different. Try disabling VPN,
proxy or network accelerators." if the STUN request has returned an IP
address different from the one obtained via HTTP from info2.ddnet.tw.
"No answer from server yet." otherwise, if the STUN request has returned
no interesting data, indicating that it's likely the game server's
fault.
Previously, only Linux used an internal buffer (for optimized
receiving). Now all OSs use an internal buffer so that the call to
`net_udp_recv` behaves the same on all platforms.
Purely automatic change. In case of conflict with this change, apply the
other change and rerun the formatting to restore it:
$ python scripts/fix_style.py
This means that we have a reliable and fast way to query for extended info,
while also not wasting network bandwidth.
The protocol is designed to be extensible, there's four bytes space for
encoding more request types (currently zeroed), and there's one string in each
response packet and one string for each player available (currently the empty
string).
The protocol itself has no problems with more than 64 players, although the
current client implementation will drop the player info after the 64th player,
because it uses a static array for storage.
Also fixes#130, the player list is just sorted each time new player info
arrives.