Merge pull request #315 from cdburkard/patches/fix_bindpy

Added support for mount namespaces in bind.py

mininet/node.py

@@ -16,6 +16,11 @@ Host: a virtual host. By default, a host is simply a shell; commands
 CPULimitedHost: a virtual host whose CPU bandwidth is limited by
     RT or CFS bandwidth limiting.
 
+HostWithPrivateDirs: a virtual host that has user-specified private
+    directories. These may be temporary directories stored as a tmpfs,
+    or persistent directories that are mounted from another directory in
+    the root filesystem.
+
 Switch: superclass for switch nodes.
 
 UserSwitch: a switch using the user-space switch from the OpenFlow
@@ -725,6 +730,33 @@ class CPULimitedHost( Host ):
         mountCgroups()
         cls.inited = True
 
+class HostWithPrivateDirs( Host ):
+    "Host with private directories"
+
+    def __init__( self, name, *args, **kwargs ):
+        "privateDirs: list of private directory strings or tuples"
+        self.name = name
+        self.privateDirs = kwargs.pop( 'privateDirs', [] )
+        Host.__init__( self, name, *args, **kwargs )
+        self.mountPrivateDirs()
+
+    def mountPrivateDirs( self ):
+        "mount private directories"
+        for directory in self.privateDirs:
+            if isinstance( directory, tuple ):
+                # mount given private directory
+                privateDir = directory[ 1 ] % self.__dict__ 
+                mountPoint = directory[ 0 ]
+                self.cmd( 'mkdir -p %s' % privateDir )
+                self.cmd( 'mkdir -p %s' % mountPoint )
+                self.cmd( 'mount --bind %s %s' %
+                               ( privateDir, mountPoint ) )
+            else:
+                # mount temporary filesystem on directory
+                self.cmd( 'mkdir -p %s' % directory ) 
+                self.cmd( 'mount -n -t tmpfs tmpfs %s' % directory )
+
+
 
 # Some important things to note:
 #