1 files changed, 246 insertions, 0 deletions

diff --git a/src/OSSupport/Network.h b/src/OSSupport/Network.h
new file mode 100644
index 000000000..cdf6ba0e9
--- /dev/null
+++ b/src/OSSupport/Network.h
@@ -0,0 +1,246 @@
+
+// Network.h
+
+// Declares the classes used for the Network API
+
+
+
+
+
+#pragma once
+
+
+
+
+
+// fwd:
+class cTCPLink;
+typedef SharedPtr<cTCPLink> cTCPLinkPtr;
+typedef std::vector<cTCPLinkPtr> cTCPLinkPtrs;
+class cServerHandle;
+typedef SharedPtr<cServerHandle> cServerHandlePtr;
+typedef std::vector<cServerHandlePtr> cServerHandlePtrs;
+
+
+
+
+
+/** Interface that provides the methods available on a single TCP connection. */
+class cTCPLink
+{
+	friend class cNetwork;
+
+public:
+	class cCallbacks
+	{
+	public:
+		// Force a virtual destructor for all descendants:
+		virtual ~cCallbacks() {}
+
+		/** Called when the cTCPLink for the connection is created.
+		The callback may store the cTCPLink instance for later use, but it should remove it in OnError(), OnRemoteClosed() or right after Close(). */
+		virtual void OnLinkCreated(cTCPLinkPtr a_Link) = 0;
+
+		/** Called when there's data incoming from the remote peer. */
+		virtual void OnReceivedData(const char * a_Data, size_t a_Length) = 0;
+
+		/** Called when the remote end closes the connection.
+		The link is still available for connection information query (IP / port).
+		Sending data on the link is not an error, but the data won't be delivered. */
+		virtual void OnRemoteClosed(void) = 0;
+
+		/** Called when an error is detected on the connection. */
+		virtual void OnError(int a_ErrorCode, const AString & a_ErrorMsg) = 0;
+	};
+	typedef SharedPtr<cCallbacks> cCallbacksPtr;
+
+
+	// Force a virtual destructor for all descendants:
+	virtual ~cTCPLink() {}
+
+	/** Queues the specified data for sending to the remote peer.
+	Returns true on success, false on failure. Note that this success or failure only reports the queue status, not the actual data delivery. */
+	virtual bool Send(const void * a_Data, size_t a_Length) = 0;
+
+	/** Queues the specified data for sending to the remote peer.
+	Returns true on success, false on failure. Note that this success or failure only reports the queue status, not the actual data delivery. */
+	bool Send(const AString & a_Data)
+	{
+		return Send(a_Data.data(), a_Data.size());
+	}
+
+	/** Returns the IP address of the local endpoint of the connection. */
+	virtual AString GetLocalIP(void) const = 0;
+
+	/** Returns the port used by the local endpoint of the connection. */
+	virtual UInt16 GetLocalPort(void) const = 0;
+
+	/** Returns the IP address of the remote endpoint of the connection. */
+	virtual AString GetRemoteIP(void) const = 0;
+
+	/** Returns the port used by the remote endpoint of the connection. */
+	virtual UInt16 GetRemotePort(void) const = 0;
+
+	/** Closes the link gracefully.
+	The link will send any queued outgoing data, then it will send the FIN packet.
+	The link will still receive incoming data from remote until the remote closes the connection. */
+	virtual void Shutdown(void) = 0;
+
+	/** Drops the connection without any more processing.
+	Sends the RST packet, queued outgoing and incoming data is lost. */
+	virtual void Close(void) = 0;
+
+protected:
+	/** Callbacks to be used for the various situations. */
+	cCallbacksPtr m_Callbacks;
+
+
+	/** Creates a new link, with the specified callbacks. */
+	cTCPLink(cCallbacksPtr a_Callbacks):
+		m_Callbacks(a_Callbacks)
+	{
+	}
+};
+
+
+
+
+
+/** Interface that provides the methods available on a listening server socket. */
+class cServerHandle
+{
+	friend class cNetwork;
+public:
+
+	// Force a virtual destructor for all descendants:
+	virtual ~cServerHandle() {}
+
+	/** Stops the server, no more incoming connections will be accepted.
+	All current connections will be shut down (cTCPLink::Shutdown()). */
+	virtual void Close(void) = 0;
+
+	/** Returns true if the server has been started correctly and is currently listening for incoming connections. */
+	virtual bool IsListening(void) const = 0;
+};
+
+
+
+
+
+class cNetwork
+{
+public:
+	/** Callbacks used for connecting to other servers as a client. */
+	class cConnectCallbacks
+	{
+	public:
+		// Force a virtual destructor for all descendants:
+		virtual ~cConnectCallbacks() {}
+
+		/** Called when the Connect call succeeds.
+		Provides the newly created link that can be used for communication. */
+		virtual void OnConnected(cTCPLink & a_Link) = 0;
+
+		/** Called when the Connect call fails. */
+		virtual void OnError(int a_ErrorCode, const AString & a_ErrorMsg) = 0;
+	};
+	typedef SharedPtr<cConnectCallbacks> cConnectCallbacksPtr;
+
+
+	/** Callbacks used when listening for incoming connections as a server. */
+	class cListenCallbacks
+	{
+	public:
+		// Force a virtual destructor for all descendants:
+		virtual ~cListenCallbacks() {}
+
+		/** Called when the TCP server created with Listen() receives a new incoming connection.
+		Returns the link callbacks that the server should use for the newly created link.
+		If a nullptr is returned, the connection is dropped immediately;
+		otherwise a new cTCPLink instance is created and OnAccepted() is called. */
+		virtual cTCPLink::cCallbacksPtr OnIncomingConnection(const AString & a_RemoteIPAddress, UInt16 a_RemotePort) = 0;
+
+		/** Called when the TCP server created with Listen() creates a new link for an incoming connection.
+		Provides the newly created Link that can be used for communication.
+		Called right after a successful OnIncomingConnection(). */
+		virtual void OnAccepted(cTCPLink & a_Link) = 0;
+
+		/** Called when the socket fails to listen on the specified port. */
+		virtual void OnError(int a_ErrorCode, const AString & a_ErrorMsg) = 0;
+	};
+	typedef SharedPtr<cListenCallbacks> cListenCallbacksPtr;
+
+
+	/** Callbacks used when resolving names to IPs. */
+	class cResolveNameCallbacks
+	{
+	public:
+		// Force a virtual destructor for all descendants:
+		virtual ~cResolveNameCallbacks() {}
+
+		/** Called when the hostname is successfully resolved into an IP address.
+		May be called multiple times if a name resolves to multiple addresses.
+		a_IP may be either an IPv4 or an IPv6 address with their proper formatting. */
+		virtual void OnNameResolved(const AString & a_Name, const AString & a_IP) = 0;
+
+		/** Called when an error is encountered while resolving.
+		If an error is reported, the OnFinished() callback is not called. */
+		virtual void OnError(int a_ErrorCode, const AString & a_ErrorMsg) = 0;
+
+		/** Called when all the addresses resolved have been reported via the OnNameResolved() callback.
+		Only called if there was no error reported. */
+		virtual void OnFinished(void) = 0;
+	};
+	typedef SharedPtr<cResolveNameCallbacks> cResolveNameCallbacksPtr;
+
+
+	/** Queues a TCP connection to be made to the specified host.
+	Calls one the connection callbacks (success, error) when the connection is successfully established, or upon failure.
+	The a_LinkCallbacks is passed to the newly created cTCPLink.
+	Returns true if queueing was successful, false on failure to queue.
+	Note that the return value doesn't report the success of the actual connection; the connection is established asynchronously in the background.
+	Implemented in TCPLinkImpl.cpp. */
+	static bool Connect(
+		const AString & a_Host,
+		UInt16 a_Port,
+		cConnectCallbacksPtr a_ConnectCallbacks,
+		cTCPLink::cCallbacksPtr a_LinkCallbacks
+	);
+
+
+	/** Opens up the specified port for incoming connections.
+	Calls an OnAccepted callback for each incoming connection.
+	A cTCPLink with the specified link callbacks is created for each connection.
+	Returns a cServerHandle that can be used to query the operation status and close the server.
+	Implemented in ServerHandleImpl.cpp. */
+	static cServerHandlePtr Listen(
+		UInt16 a_Port,
+		cListenCallbacksPtr a_ListenCallbacks
+	);
+
+
+	/** Queues a DNS query to resolve the specified hostname to IP address.
+	Calls one of the callbacks when the resolving succeeds, or when it fails.
+	Returns true if queueing was successful, false if not.
+	Note that the return value doesn't report the success of the actual lookup; the lookup happens asynchronously on the background.
+	Implemented in HostnameLookup.cpp. */
+	static bool HostnameToIP(
+		const AString & a_Hostname,
+		cResolveNameCallbacksPtr a_Callbacks
+	);
+
+
+	/** Queues a DNS query to resolve the specified IP address to a hostname.
+	Calls one of the callbacks when the resolving succeeds, or when it fails.
+	Returns true if queueing was successful, false if not.
+	Note that the return value doesn't report the success of the actual lookup; the lookup happens asynchronously on the background.
+	Implemented in IPLookup.cpp. */
+	static bool IPToHostName(
+		const AString & a_IP,
+		cResolveNameCallbacksPtr a_Callbacks
+	);
+};
+
+
+
+