Replace None with a new NoEntry class.

Signed-off-by: Anders Kaseorg <andersk@mit.edu>

diff --git a/routefs/__init__.py b/routefs/__init__.py
index 875345b..61816b7 100644 (file)
--- a/routefs/__init__.py
+++ b/routefs/__init__.py
@@ -83,7 +83,7 @@ class RouteFS(fuse.Fuse):
         """
         match = self.map.match(path)
         if match is None:
         """
         match = self.map.match(path)
         if match is None:

-            return
+            return NoEntry()

         controller = match.pop('controller')
         result = getattr(self, controller)(**match)
         if type(result) is str:
         controller = match.pop('controller')
         result = getattr(self, controller)(**match)
         if type(result) is str:

@@ -112,7 +112,7 @@ class RouteFS(fuse.Fuse):
         predetermined based on which it is.
         """
         obj = self._get_file(path)
         predetermined based on which it is.
         """
         obj = self._get_file(path)

-        if obj is None:
+        if type(obj) is NoEntry:

             return -errno.ENOENT
         
         st = RouteStat()
             return -errno.ENOENT
         
         st = RouteStat()

@@ -136,7 +136,7 @@ class RouteFS(fuse.Fuse):
         of the file
         """
         obj = self._get_file(path)
         of the file
         """
         obj = self._get_file(path)

-        if obj is None:
+        if type(obj) is NoEntry:

             return -errno.ENOENT
         elif type(obj) in (Directory, Symlink):
             return -errno.EINVAL
             return -errno.ENOENT
         elif type(obj) in (Directory, Symlink):
             return -errno.EINVAL

@@ -155,7 +155,13 @@ class RouteFS(fuse.Fuse):
         else:
             return obj
 
         else:
             return obj
 

-class TreeEntry(object):
+class TreeKey(object):
+    pass
+
+class NoEntry(TreeKey):
+    pass
+
+class TreeEntry(TreeKey):

     default_mode = 0444
     
     def __new__(cls, contents, mode=None):
     default_mode = 0444
     
     def __new__(cls, contents, mode=None):