added TcpConnection::fileno() to expose the internal filedescriptor / socket

include/tcpconnection.h

@@ -117,6 +117,12 @@ public:
      */
     virtual ~TcpConnection() noexcept {}
 
+    /**
+     *  The filedescriptor that is used for this connection
+     *  @return int
+     */
+    int fileno() const;
+
     /**
      *  Process the TCP connection
      * 

src/tcpconnected.h

@@ -142,6 +142,12 @@ public:
         // close the socket
         close(_socket);
     }
+
+    /**
+     *  The filedescriptor of this connection
+     *  @return int
+     */
+    virtual int fileno() const override { return _socket; }
     
     /**
      *  Process the filedescriptor in the object

src/tcpconnection.cpp

@@ -27,6 +27,16 @@ TcpConnection::TcpConnection(TcpHandler *handler, const Address &address) :
     _state(new TcpResolver(this, address.hostname(), address.port(), handler)),
     _connection(this, address.login(), address.vhost()) {}
 
+/**
+ *  The filedescriptor that is used for this connection
+ *  @return int
+ */
+int TcpConnection::fileno() const
+{
+    // pass on to the state object
+    return _state->fileno();
+}
+
 /**
  *  Process the TCP connection
  *  This method should be called when the filedescriptor that is registered

src/tcpstate.h

@@ -57,6 +57,12 @@ public:
      */
     virtual ~TcpState() = default;
 
+    /**
+     *  The filedescriptor of this connection
+     *  @return int
+     */
+    virtual int fileno() const { return -1; }
+
     /**
      *  Process the filedescriptor in the object    
      *  @param  fd          The filedescriptor that is active