use select to check for network data

oml/localnodes.py

@@ -8,6 +8,7 @@ import struct
 import _thread
 from threading import Thread
 import time
+import select
 
 from utils import valid, get_public_ipv6, get_local_ipv4, get_interface
 from settings import preferences, server, USER_ID, sk
@@ -51,7 +52,6 @@ class LocalNodesBase(Thread):
 
     _PORT = 9851 
     _TTL = 1
-    _TIMEOUT = 30
 
     def __init__(self, nodes):
         self._socket = None
@@ -85,12 +85,12 @@ class LocalNodesBase(Thread):
 
     def receive(self):
         last = time.mktime(time.localtime())
+        s = self.get_socket()
+        s.bind(('', self._PORT))
         while self._active:
             try:
-                s = self.get_socket()
-                s.settimeout(self._TIMEOUT)
-                s.bind(('', self._PORT))
-                while self._active:
+                r, _, _ = select.select([s], [], [], 3)
+                if r:
                     data, addr = s.recvfrom(1024)
                     if self._active:
                         while data[-1] == 0:
@@ -98,8 +98,6 @@ class LocalNodesBase(Thread):
                         data = self.verify(data)
                         if data:
                             self.update_node(data)
-            except socket.timeout:
-                pass
             except OSError: # no local interface exists
                 self.wait(60)
             except: