OpenTTD Source  20241121-master-g67a0fccfad
tcp.h
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1 /*
2  * This file is part of OpenTTD.
3  * OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2.
4  * OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
5  * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
6  */
7 
12 #ifndef NETWORK_CORE_TCP_H
13 #define NETWORK_CORE_TCP_H
14 
15 #include "address.h"
16 #include "packet.h"
17 
18 #include <atomic>
19 #include <chrono>
20 #include <thread>
21 
28 };
29 
32 private:
33  std::deque<std::unique_ptr<Packet>> packet_queue;
34  std::unique_ptr<Packet> packet_recv;
35 
36  void EmptyPacketQueue();
37 public:
38  SOCKET sock;
39  bool writable;
40 
45  bool IsConnected() const { return this->sock != INVALID_SOCKET; }
46 
47  virtual NetworkRecvStatus CloseConnection(bool error = true);
48  void CloseSocket();
49 
50  virtual void SendPacket(std::unique_ptr<Packet> &&packet);
51  SendPacketsState SendPackets(bool closing_down = false);
52 
53  virtual std::unique_ptr<Packet> ReceivePacket();
54 
55  bool CanSendReceive();
56 
61  bool HasSendQueue() { return !this->packet_queue.empty(); }
62 
63  NetworkTCPSocketHandler(SOCKET s = INVALID_SOCKET);
65 };
66 
70 class TCPConnecter {
71 private:
79  enum class Status {
80  Init,
81  Resolving,
82  Failure,
83  Connecting,
84  Connected,
85  };
86 
87  std::thread resolve_thread;
88  std::atomic<Status> status = Status::Init;
89  std::atomic<bool> killed = false;
90 
91  addrinfo *ai = nullptr;
92  std::vector<addrinfo *> addresses;
93  std::map<SOCKET, NetworkAddress> sock_to_address;
94  size_t current_address = 0;
95 
96  std::vector<SOCKET> sockets;
97  std::chrono::steady_clock::time_point last_attempt;
98 
99  std::string connection_string;
101  int family = AF_UNSPEC;
102 
103  static std::vector<std::shared_ptr<TCPConnecter>> connecters;
104 
105  void Resolve();
106  void OnResolved(addrinfo *ai);
107  bool TryNextAddress();
108  void Connect(addrinfo *address);
109  virtual bool CheckActivity();
110 
111  /* We do not want any other derived classes from this class being able to
112  * access these private members, but it is okay for TCPServerConnecter. */
113  friend class TCPServerConnecter;
114 
115  static void ResolveThunk(TCPConnecter *connecter);
116 
117 public:
118  TCPConnecter() {};
119  TCPConnecter(const std::string &connection_string, uint16_t default_port, const NetworkAddress &bind_address = {}, int family = AF_UNSPEC);
120  virtual ~TCPConnecter();
121 
126  virtual void OnConnect([[maybe_unused]] SOCKET s) {}
127 
131  virtual void OnFailure() {}
132 
133  void Kill();
134 
135  static void CheckCallbacks();
136  static void KillAll();
137 
144  template <class T, typename... Args>
145  static std::shared_ptr<TCPConnecter> Create(Args&& ... args)
146  {
147  return TCPConnecter::connecters.emplace_back(std::make_shared<T>(std::forward<Args>(args)...));
148  }
149 };
150 
152 private:
153  SOCKET socket = INVALID_SOCKET;
154 
155  bool CheckActivity() override;
156 
157 public:
159 
160  TCPServerConnecter(const std::string &connection_string, uint16_t default_port);
161 
162  void SetConnected(SOCKET sock);
163  void SetFailure();
164 };
165 
166 #endif /* NETWORK_CORE_TCP_H */
Wrapper for network addresses.
Wrapper for (un)resolved network addresses; there's no reason to transform a numeric IP to a string a...
Definition: address.h:28
SocketHandler for all network sockets in OpenTTD.
Definition: core.h:43
Base socket handler for all TCP sockets.
Definition: tcp.h:31
std::deque< std::unique_ptr< Packet > > packet_queue
Packets that are awaiting delivery. Cannot be std::queue as that does not have a clear() function.
Definition: tcp.h:33
virtual NetworkRecvStatus CloseConnection(bool error=true)
This will put this socket handler in a close state.
Definition: tcp.cpp:51
virtual std::unique_ptr< Packet > ReceivePacket()
Receives a packet for the given client.
Definition: tcp.cpp:129
bool IsConnected() const
Whether this socket is currently bound to a socket.
Definition: tcp.h:45
NetworkTCPSocketHandler(SOCKET s=INVALID_SOCKET)
Construct a socket handler for a TCP connection.
Definition: tcp.cpp:23
SOCKET sock
The socket currently connected to.
Definition: tcp.h:38
bool writable
Can we write to this socket?
Definition: tcp.h:39
virtual void SendPacket(std::unique_ptr< Packet > &&packet)
This function puts the packet in the send-queue and it is send as soon as possible.
Definition: tcp.cpp:68
SendPacketsState SendPackets(bool closing_down=false)
Sends all the buffered packets out for this client.
Definition: tcp.cpp:86
void CloseSocket()
Close the actual socket of the connection.
Definition: tcp.cpp:39
bool CanSendReceive()
Check whether this socket can send or receive something.
Definition: tcp.cpp:204
std::unique_ptr< Packet > packet_recv
Partially received packet.
Definition: tcp.h:34
bool HasSendQueue()
Whether there is something pending in the send queue.
Definition: tcp.h:61
Address to a game server.
Definition: address.h:196
"Helper" class for creating TCP connections in a non-blocking manner
Definition: tcp.h:70
NetworkAddress bind_address
Address we're binding to, if any.
Definition: tcp.h:100
void Kill()
Kill this connecter.
Definition: tcp_connect.cpp:78
std::chrono::steady_clock::time_point last_attempt
Time we last tried to connect.
Definition: tcp.h:97
virtual void OnConnect([[maybe_unused]] SOCKET s)
Callback when the connection succeeded.
Definition: tcp.h:126
std::atomic< Status > status
The current status of the connecter.
Definition: tcp.h:88
std::string connection_string
Current address we are connecting to (before resolving).
Definition: tcp.h:99
static std::vector< std::shared_ptr< TCPConnecter > > connecters
List of connections that are currently being created.
Definition: tcp.h:103
std::vector< SOCKET > sockets
Pending connect() attempts.
Definition: tcp.h:96
static void CheckCallbacks()
Check whether we need to call the callback, i.e.
Status
The current status of the connecter.
Definition: tcp.h:79
@ Connected
The connection is established.
@ Resolving
The hostname is being resolved (threaded).
@ Init
TCPConnecter is created but resolving hasn't started.
@ Failure
Resolving failed.
@ Connecting
We are currently connecting.
size_t current_address
Current index in addresses we are trying.
Definition: tcp.h:94
void Resolve()
Start resolving the hostname.
static std::shared_ptr< TCPConnecter > Create(Args &&... args)
Create the connecter, and initiate connecting by putting it in the collection of TCP connections to m...
Definition: tcp.h:145
virtual void OnFailure()
Callback for when the connection attempt failed.
Definition: tcp.h:131
void OnResolved(addrinfo *ai)
Callback when resolving is done.
virtual bool CheckActivity()
Check if there was activity for this connecter.
std::map< SOCKET, NetworkAddress > sock_to_address
Mapping of a socket to the real address it is connecting to. USed for DEBUG statements.
Definition: tcp.h:93
static void ResolveThunk(TCPConnecter *connecter)
Thunk to start Resolve() on the right instance.
std::vector< addrinfo * > addresses
Addresses we can connect to.
Definition: tcp.h:92
std::thread resolve_thread
Thread used during resolving.
Definition: tcp.h:87
static void KillAll()
Kill all connection attempts.
bool TryNextAddress()
Start the connect() for the next address in the list.
std::atomic< bool > killed
Whether this connecter is marked as killed.
Definition: tcp.h:89
void Connect(addrinfo *address)
Start a connection to the indicated address.
Definition: tcp_connect.cpp:88
addrinfo * ai
getaddrinfo() allocated linked-list of resolved addresses.
Definition: tcp.h:91
int family
Family we are using to connect with.
Definition: tcp.h:101
void SetConnected(SOCKET sock)
The connection was successfully established.
bool CheckActivity() override
Check if there was activity for this connecter.
ServerAddress server_address
Address we are connecting to.
Definition: tcp.h:158
void SetFailure()
The connection couldn't be established.
SOCKET socket
The socket when a connection is established.
Definition: tcp.h:153
NetworkRecvStatus
Status of a network client; reasons why a client has quit.
Definition: core.h:23
Basic functions to create, fill and read packets.
SendPacketsState
The states of sending the packets.
Definition: tcp.h:23
@ SPS_PARTLY_SENT
The packets are partly sent; there are more packets to be sent in the queue.
Definition: tcp.h:26
@ SPS_ALL_SENT
All packets in the queue are sent.
Definition: tcp.h:27
@ SPS_NONE_SENT
The buffer is still full, so no (parts of) packets could be sent.
Definition: tcp.h:25
@ SPS_CLOSED
The connection got closed.
Definition: tcp.h:24