Handle socket.IPV6_MULTICAST_IF failing to be set

Author: bdraco

wsdiscovery/threaded.py

@@ -121,7 +121,15 @@ def _createMulticastOutSocket(self, addr, ttl):
         else:
             iface = int(addr.scope_id)
 
-        sock.setsockopt(ip_proto, self._get_multicast(), iface)
+        try:
+            sock.setsockopt(ip_proto, self._get_multicast(), iface)
+        except OSError as e:
+            logger.warning(
+                "Interface for %s does not support "
+                "multicast flags or is not UP: OSError %s",
+                addr,
+                e
+            )
 
         return sock
 
@@ -142,7 +150,7 @@ def addSourceAddr(self, addr):
         try:
             self._multiInSocket.setsockopt(self._get_ip_proto(), self._get_ip_join(), self._makeMreq(addr))
         except socket.error as e:
-            logger.debug(f"Interface has more than 1 address: {e}")
+            logger.warning(f"Interface has more than 1 address: {e}")
 
         sock = self._createMulticastOutSocket(addr, self._observer.ttl)
         self._multiOutUniInSockets[addr] = sock
@@ -152,7 +160,7 @@ def removeSourceAddr(self, addr):
         try:
             self._multiInSocket.setsockopt(self._get_ip_proto(), self._get_ip_leave(), self._makeMreq(addr))
         except socket.error as e:
-            logger.debug(f"Interface has more than 1 address: {e}")
+            logger.warning(f"Interface has more than 1 address: {e}")
 
         sock = self._multiOutUniInSockets[addr]
         self._selector.unregister(sock)
@@ -388,36 +396,33 @@ def _startThreads(self):
             return
 
         self._networkingThread_v4 = NetworkingThreadIPv4(self)
+        self._networkingThread_v6 = NetworkingThreadIPv6(self)
         self._networkingThread_v4.start()
-        self._addrsMonitorThread_v4 = AddressMonitorThread(self, socket.AF_INET)
-        self._addrsMonitorThread_v4.start()
+        self._networkingThread_v6.start()
         logger.debug("networking threads started")
 
-        try:
-            self._networkingThread_v6 = NetworkingThreadIPv6(self)
-            self._networkingThread_v6.start()
-            self._addrsMonitorThread_v6 = AddressMonitorThread(self, socket.AF_INET6)
-            self._addrsMonitorThread_v6.start()
-        except OSError as e:
-            logger.debug("IPv6 not supported: %s", e)
-            self._networkingThread_v6 = None
-            self._addrsMonitorThread_v6 = None
+        self._addrsMonitorThread_v4 = AddressMonitorThread(self, socket.AF_INET)
+        self._addrsMonitorThread_v6 = AddressMonitorThread(self, socket.AF_INET6)
+        self._addrsMonitorThread_v4.start()
+        self._addrsMonitorThread_v6.start()
         logger.debug("address monitoring threads started")
 
     def _stopThreads(self):
-        if self._networkingThread_v4 is not None:
-            self._networkingThread_v4.schedule_stop()
-            self._addrsMonitorThread_v4.schedule_stop()
-            self._networkingThread_v4.join()
-            self._addrsMonitorThread_v4.join()
-            self._networkingThread_v4 = None
-
-        if self._networkingThread_v6 is not None:
-            self._networkingThread_v6.schedule_stop()
-            self._addrsMonitorThread_v6.schedule_stop()
-            self._networkingThread_v6.join()
-            self._addrsMonitorThread_v6.join()
-            self._networkingThread_v6 = None
+        if self._networkingThread_v4 is None:
+            return
+
+        self._networkingThread_v4.schedule_stop()
+        self._addrsMonitorThread_v4.schedule_stop()
+        self._networkingThread_v6.schedule_stop()
+        self._addrsMonitorThread_v6.schedule_stop()
+
+        self._networkingThread_v4.join()
+        self._addrsMonitorThread_v4.join()
+        self._networkingThread_v6.join()
+        self._addrsMonitorThread_v6.join()
+
+        self._networkingThread_v4 = None
+        self._networkingThread_v6 = None
 
     def start(self):
         """start networking - should be called before using other methods"""
@@ -433,24 +438,23 @@ def addSourceAddr(self, addr):
         version = ipaddress.ip_address(addr).version
         if version == 4:
             self._networkingThread_v4.addSourceAddr(addr)
-        elif version == 6 and self._networkingThread_v6 is not None:
+        elif version == 6:
             self._networkingThread_v6.addSourceAddr(addr)
 
     def removeSourceAddr(self, addr):
         version = ipaddress.ip_address(addr).version
         if version == 4:
             self._networkingThread_v4.removeSourceAddr(addr)
-        elif version == 6 and self._networkingThread_v6 is not None:
+        elif version == 6:
             self._networkingThread_v6.removeSourceAddr(addr)
 
     def sendUnicastMessage(self, env, host, port, initialDelay=0,
                            unicast_num=UNICAST_UDP_REPEAT):
         "handle unicast message sending"
         self._networkingThread_v4.addUnicastMessage(env, host, port,
                                                     initialDelay, unicast_num)
-        if self._networkingThread_v6 is not None:
-            self._networkingThread_v6.addUnicastMessage(env, host, port,
-                                                        initialDelay, unicast_num)
+        self._networkingThread_v6.addUnicastMessage(env, host, port,
+                                                    initialDelay, unicast_num)
 
     def sendMulticastMessage(self, env, initialDelay=0,
                              multicast_num=MULTICAST_UDP_REPEAT):
@@ -460,8 +464,7 @@ def sendMulticastMessage(self, env, initialDelay=0,
                                                       MULTICAST_PORT,
                                                       initialDelay,
                                                       multicast_num)
-        if self._networkingThread_v6 is not None:
-            self._networkingThread_v6.addMulticastMessage(env,
+        self._networkingThread_v6.addMulticastMessage(env,
                                                       MULTICAST_IPV6_ADDRESS,
                                                       MULTICAST_PORT,
                                                       initialDelay,