Node class: Keep track of processes, make unshare optional.

src/netns/node.py

@@ -12,16 +12,17 @@ class Node(object):
         s = sorted(Node._nodes.items(), key = lambda x: x[0])
         return [ x[1] for x in s ]
 
-    def __init__(self, debug = False):
+    def __init__(self, debug = False, nonetns = False):
         """Create a new node in the emulation. Implemented as a separate
         process in a new network name space. Requires root privileges to run.
 
         If keepns is true, the network name space is not created and can be run
         as a normal user, for testing. If debug is true, details of the
         communication protocol are printed on stderr."""
-        fd, pid = _start_child(debug)
+        fd, pid = _start_child(debug, nonetns)
         self._pid = pid
         self._slave = netns.protocol.Client(fd, debug)
+        self._processes = weakref.WeakValueDictionary()
         Node._nodes[Node._nextnode] = self
         Node._nextnode += 1
 
@@ -29,10 +30,15 @@ class Node(object):
         self.shutdown()
 
     def shutdown(self):
-        self._slave.shutdown()
+        for p in self._processes:
+            p.destroy()
+        del self._processes
         del self._pid
+        self._slave.shutdown()
         del self._slave
 
+    def _add_subprocess(self, subprocess):
+        self._processes[subprocess.pid] = subprocess
     @property
     def pid(self):
         return self._pid
@@ -43,7 +49,7 @@ class Node(object):
     def add_default_route(self, nexthop, interface = None):
         return self.add_route('0.0.0.0', 0, nexthop, interface)
     def start_process(self, args):
-        return Process()
+        return netns.subprocess.start_process(node, args)
     def run_process(self, args):
         return ("", "")
     def get_routes(self):
@@ -60,15 +66,10 @@ class Interface(object):
     def add_v6_address(self, address, prefix_len):
         pass
 
-class Process(object):
-    def __init__(self):
-        self.pid = os.getpid()
-        self.valid = True
-
 # Handle the creation of the child; parent gets (fd, pid), child creates and
 # runs a Server(); never returns.
 # Requires CAP_SYS_ADMIN privileges to run.
-def _start_child(debug = False):
+def _start_child(debug, nonetns):
     # Create socket pair to communicate
     (s0, s1) = socket.socketpair(socket.AF_UNIX, socket.SOCK_STREAM, 0)
     # Spawn a child that will run in a loop
@@ -81,7 +82,8 @@ def _start_child(debug = False):
     try:
         s0.close()
         srv = netns.protocol.Server(s1, debug)
-        unshare.unshare(unshare.CLONE_NEWNET)
+        if not nonetns:
+            unshare.unshare(unshare.CLONE_NEWNET)
         srv.run()
     except BaseException, e:
         s = "Slave node aborting: %s\n" % str(e)