From c7396d882d9816b196e50e8363af1c015342d2bc Mon Sep 17 00:00:00 2001
From: Alberto Sottile <alby128@gmail.com>
Date: Fri, 25 Jan 2019 15:51:53 +0100
Subject: [PATCH] IPv6: revert to listenTCP and override createInternetSocket
 to have a dual stack server

---
 syncplayServer.py | 21 ++++++++++++++++-----
 1 file changed, 16 insertions(+), 5 deletions(-)

diff --git a/syncplayServer.py b/syncplayServer.py
index 62431fc..b8ca65a 100755
--- a/syncplayServer.py
+++ b/syncplayServer.py
@@ -1,6 +1,7 @@
 #!/usr/bin/env python3
 #coding:utf8
 
+import socket
 import sys
 
 # libpath
@@ -12,16 +13,24 @@ except AttributeError:
     import warnings
     warnings.warn("You must run Syncplay with Python 3.4 or newer!")
 
-from twisted.internet.endpoints import TCP6ServerEndpoint
-from twisted.internet import reactor
+from twisted.internet import reactor, tcp
 
 from syncplay.server import SyncFactory, ConfigurationGetter
 
+class DualStackPort(tcp.Port):
+
+    def __init__(self, port, factory, backlog=50, interface='', reactor=None):
+        tcp.Port.__init__(self, port, factory, backlog, interface, reactor)
+
+    def createInternetSocket(self):
+        s = tcp.Port.createInternetSocket(self)
+        s.setsockopt(socket.IPPROTO_IPV6, socket.IPV6_V6ONLY, 0)
+        return s
+
 if __name__ == '__main__':
     argsGetter = ConfigurationGetter()
     args = argsGetter.getConfiguration()
-    endpoint = TCP6ServerEndpoint(reactor, int(args.port))
-    endpoint.listen(
+    dsp = DualStackPort(int(args.port),
         SyncFactory(
             args.port,
             args.password,
@@ -32,5 +41,7 @@ if __name__ == '__main__':
             args.disable_chat,
             args.max_chat_message_length,
             args.max_username_length,
-            args.stats_db_file))
+            args.stats_db_file),
+        interface='::')
+    dsp.startListening()
     reactor.run()