Replace addrinfo with socket() static method.

WebSocketServer.socket() is a static method takes a host and port and
an optional connect parameter. If connect is not set then it returns
a socket listening on host and port. If connect is set then
a connection will be made host and port and the socket returned. This
has IPv6 support like the addrinfo method it replaces.

Also, prefer IPv4 resolutions if they are in the list. This can be
overriden to prefer IPv6 resolutions for the same host using the
optional prefer_ipv6 parameter.

websocket.py

@@ -144,16 +144,33 @@ Sec-WebSocket-Accept: %s\r
     #
 
     @staticmethod
-    def addrinfo(host, port=None):
-        """ Resolve a host (and optional port) to an IPv4 or IPv6 address.
-        Returns: family, socktype, proto, canonname, sockaddr
+    def socket(host, port=None, connect=False, prefer_ipv6=False):
+        """ Resolve a host (and optional port) to an IPv4 or IPv6
+        address. Create a socket. Bind to it if listen is set,
+        otherwise connect to it. Return the socket.
         """
-        if not host:
-            host = 'localhost'
-        addrs = socket.getaddrinfo(host, port, 0, socket.SOCK_STREAM, socket.IPPROTO_TCP)
+        flags = 0
+        if host == '':
+            host = None
+        if connect and not port:
+            raise Exception("Connect mode requires a port")
+        if not connect:
+            flags = flags | socket.AI_PASSIVE
+        addrs = socket.getaddrinfo(host, port, 0, socket.SOCK_STREAM,
+                socket.IPPROTO_TCP, flags)
         if not addrs:
             raise Exception("Could resolve host '%s'" % host)
-        return addrs[0]
+        addrs.sort(key=lambda x: x[0])
+        if prefer_ipv6:
+            addrs.reverse()
+        sock = socket.socket(addrs[0][0], addrs[0][1])
+        if connect:
+            sock.connect(addrs[0][4])
+        else:
+            sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
+            sock.bind(addrs[0][4])
+            sock.listen(100)
+        return sock
 
     @staticmethod
     def daemonize(keepfd=None, chdir='/'):
@@ -738,11 +755,7 @@ Sec-WebSocket-Accept: %s\r
         is a WebSockets client then call new_client() method (which must
         be overridden) for each new client connection.
         """
-        addr = self.addrinfo(self.listen_host, self.listen_port)
-        lsock = socket.socket(addr[0], addr[1])
-        lsock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
-        lsock.bind((self.listen_host, self.listen_port))
-        lsock.listen(100)
+        lsock = self.socket(self.listen_host, self.listen_port)
 
         if self.daemon:
             self.daemonize(keepfd=lsock.fileno(), chdir=self.web)

websockify

@@ -141,9 +141,8 @@ Traffic Legend:
         # Connect to the target
         self.msg("connecting to: %s:%s" % (
                  self.target_host, self.target_port))
-        addr = self.addrinfo(self.target_host, self.target_port)
-        tsock = socket.socket(addr[0], addr[1])
-        tsock.connect((self.target_host, self.target_port))
+        tsock = self.socket(self.target_host, self.target_port,
+                connect=True)
 
         if self.verbose and not self.daemon:
             print(self.traffic_legend)