TURN is a last resort, used only if all other methods failed.
TURN is a relay approach to connect client and server together, where
openttd.org (by default) is the middleman.
It is very unlikely either the client or server cannot connect to
the STUN server, as they are both already connected to the Game
Coordinator. But in the odd case it does fail, estabilishing the
connection fails without any further possibility to recover.
Before 8a2da49 the NewGRF names were synchronized using UDP packets, however
those have been removed. With this a new version of the GameInfo packet is
introduced that allows to specify the type of serialisation happens for
NewGRFs. Either only the GRF ID and checksum, or those two plus the name of
the NewGRF.
On this request for local servers will send the NewGRFs names.
The Game Coordinator will get the names on the first registration, and after
that only the GRF ID and checksum.
These were filled with "<Unknown>" (before 8a2da49) and later their name would get filled via UDP requests to the server. These UDP packets do not exist anymore, so they will always remain "<Unknown>".
Remove that logic and just use the generic translated error GRF UNKNOWN string instead.
This method doesn't require port-forwarding to be used, and works for
most common NAT routers in home setups. But, for sure it doesn't work
for all setups, and not everyone will be able to use this.
Every outgoing connection, either TCP or UDP, triggered
NetworkInitialize(), which triggered NetworkUDPInitialize() which
first closes all connections.
Now the problem was that "Search LAN games" found a server, added
it to the list, after which (over TCP) it queries the server. This
closes all UDP sockets (as that makes sense, I guess?), while the
UDP was still reading from it.
Solve this by simply stop initializing UDP every time we make an
outgoing TCP connection; instead only do it on start-up.
In this mode you do register to the Game Coordinator, but your
server will not show up in the public server listing. You can give
your friends the invite code of the server with which they can
join.
This removes the need to know a server IP to join it. Invite codes
are small (~7 characters) indentifiers for servers, which can be
exchanged with other players to join the servers.
Normally TCPConnecter will do a DNS resolving of the connection_string
and connect to it. But for SERVER_ADDRESS_INVITE_CODE this is different:
the Game Coordinator does the "resolving".
This means we need to allow TCPConnecter to not setup a connection
and allow it to be told when a connection has been setup by an external
(to TCPConnecter) part of the code. We do this by telling the (active)
socket for the connection.
This means the rest of the code doesn't need to know the TCPConnecter
is not doing a simple resolve+connect. The rest of the code only
cares the connection is established; not how it was established.
OTTD_COORDINATOR_CS for the game coordinator defaults to coordinator.openttd.org:3976
OTTD_CONTENT_SERVER_CS for the content server defaults to content.openttd.org:3978
OTTD_CONTENT_MIRROR_CS for the content mirror server defaults to binaries.openttd.org:80
Rename the zero-parameter NetworkValidateClientName to NetworkValidateOurClientName to make it clearer it is performed on our client name, and to make it a non-overloaded function to aid with the variant being added a few commits later
* Codechange: [Network] split CloseSocket and CloseConnection more clearly
- CloseSocket now closes the actual OS socket.
- CloseConnection frees up the resources to just before CloseSocket.
- dtors call CloseSocket / CloseConnection where needed.
In the destructors of many of the network related classes Close() is called, just like the
top class in that hierarchy. However, due to virtual functions getting resolved statically
in the destructor it would always call the empty Close() of the top class.
Document the other cases where a virtual call is resolved statically.
Patric Stout
Rubidium
Loïc Guilloux
Stephan
TELK
SamuXarick
glx22
milek7