Add nodelib.py, a library of new node types

mininet/nodelib.py

@@ -0,0 +1,45 @@
+"""
+Package: nodelib
+
+Node Library for Mininet
+
+This contains additional node types which you may find to be useful
+"""
+
+from mininet.net import Mininet
+from mininet.topo import Topo
+from mininet.node import Switch
+from mininet.log import setLogLevel, info
+
+class LinuxBridge( Switch ):
+    "Linux Bridge (with optional spanning tree)"
+
+    nextPrio = 100  # next bridge priority for spanning tree
+
+    def __init__( self, name, stp=False, prio=None, **kwargs ):
+        """stp: use spanning tree protocol? (default False)
+           prio: optional explicit bridge priority for STP"""
+        self.stp = stp
+        if prio:
+            self.prio = prio
+        else:
+            self.prio = LinuxBridge.nextPrio
+            LinuxBridge.nextPrio += 1
+        Switch.__init__( self, name, **kwargs )
+
+    def start( self, controllers ):
+        self.cmd( 'ifconfig', self, 'down' )
+        self.cmd( 'brctl delbr', self )
+        self.cmd( 'brctl addbr', self )
+        if self.stp:
+            self.cmd( 'brctl setbridgeprio', self.prio )
+            self.cmd( 'brctl stp', self, 'on' )
+        for i in self.intfList():
+            if self.name in i.name:
+                self.cmd( 'brctl addif', self, i )
+        self.cmd( 'ifconfig', self, 'up' )
+
+    def stop( self ):
+        self.cmd( 'ifconfig', self, 'down' )
+        self.cmd( 'brctl delbr', self )
+