adding hwintf_topo example

examples/hwintf_topo.py

@@ -0,0 +1,61 @@
+#!/usr/bin/python
+
+"""
+This example shows how to add an interface (for example a real
+hardware interface) to a Mininet topology.
+"""
+
+import sys
+
+from mininet.cli import CLI
+from mininet.log import setLogLevel, info
+from mininet.net import Mininet
+from mininet.topo import Topo
+from mininet.link import Intf, Link
+from mininet.examples.hwintf import checkIntf
+
+class NoneIntf( Intf ):
+
+    "A dummy interface with a blank name that doesn't do any configuration"
+
+    def __init__( self, name, **params ):
+        self.name = ''
+
+class HWIntfLink( Link ):
+
+    "A dummy link that doesn't touch either interface"
+
+    def makeIntfPair( cls, intf1, intf2 ):
+        pass
+
+    def delete( self ):
+        pass
+
+class HWIntfTopo( Topo ):
+
+    "Simple one switch, two host topology with hwintf added to switch"
+
+    def __init__(self, intf, **opts):
+        Topo.__init__(self, **opts)
+
+        sw = self.addSwitch( 's1' )
+        h1 = self.addHost( 'h1' )
+        h2 = self.addHost( 'h2' )
+        self.addLink( sw, h1 )
+        self.addLink( sw, h2 )
+        self.addLink( sw, sw, cls=HWIntfLink, intfName1=intf, cls2=NoneIntf )
+
+def run():
+    # Get hwintf from command line args, and verify that it is not used
+    intfName = sys.argv[ 1 ] if len( sys.argv ) > 1 else 'eth1'
+    checkIntf( intfName )
+
+    topo = HWIntfTopo( intf=intfName )
+    net = Mininet( topo=topo )
+    net.start()
+    CLI( net )
+    net.stop()
+
+if __name__ == '__main__':
+    setLogLevel( 'info' )
+    run()