libbnetapi: Extend socket classes.

B{Abstract,Datagram,Secure}Socket:
- Add functionality to listen for and accept new connections, thus allowing
  one to use the socket classes for server functionality as well.

BSecureSocket:
- Adjust to take into account differences between how SSL needs to be called
  when accepting an incoming connection vs initiating an outbound one.
  The handshake on the accepted connection stills fails for unknown reasons
  at the moment though.

Note that these changes break the ABI, and thus any packages making use of
them directly will need a rebuild.

headers/os/net/AbstractSocket.h

@@ -1,5 +1,5 @@
 /*
- * Copyright 2011, Haiku, Inc. All Rights Reserved.
+ * Copyright 2011-2016, Haiku, Inc. All Rights Reserved.
  * Distributed under the terms of the MIT License.
  */
 #ifndef _ABSTRACT_SOCKET_H
@@ -20,8 +20,12 @@ public:
 
 			status_t			InitCheck() const;
 
-	virtual status_t			Bind(const BNetworkAddress& local) = 0;
+	virtual status_t			Bind(const BNetworkAddress& local, bool reuseAddr) = 0;
 	virtual bool				IsBound() const;
+	virtual	bool				IsListening() const;
+
+	virtual	status_t			Listen(int backlog = 10);
+	virtual	status_t			Accept(BAbstractSocket*& _socket) = 0;
 
 	virtual	status_t			Connect(const BNetworkAddress& peer,
 									bigtime_t timeout = B_INFINITE_TIMEOUT) = 0;
@@ -44,9 +48,12 @@ public:
 			int					Socket() const;
 
 protected:
-			status_t			Bind(const BNetworkAddress& local, int type);
+			status_t			Bind(const BNetworkAddress& local,
+									bool reuseAddr, int type);
 			status_t			Connect(const BNetworkAddress& peer, int type,
 									bigtime_t timeout = B_INFINITE_TIMEOUT);
+			status_t			AcceptNext(int& _acceptedSocket,
+									BNetworkAddress& _peer);
 
 private:
 			status_t			_OpenIfNeeded(int family, int type);
@@ -60,6 +67,7 @@ protected:
 			BNetworkAddress		fPeer;
 			bool				fIsBound;
 			bool				fIsConnected;
+			bool				fIsListening;
 };