added Esky.drop_root() method

ChangeLog.txt

@@ -1,11 +1,12 @@
 
-v0.6.1:
+v0.7.0:
 
     * Renamed "esky.helper" to "esky.sudo" along with much refactoring:
         * esky.use_helper_app is now esky.allow_from_sudo() and is used to 
-          declare a type signatures.
+          declare a type signature.
         * Esky.helper_app is now Esky.sudo_proxy and is always an instance
           of esky.sudo.SudoProxy.
+        * added Esky.drop_root() method to drop root privileges.
     * Use a separate file "esky-lockfile.txt" for version locking.  This
       will help protect against strange behaviour when fcntl.flock is
       simulated using fcntl.lockf (which released the lock when *any* handle

README.txt

@@ -84,6 +84,8 @@ following methods control this behaviour:
 
     app.get_root():             escalate to root privs by spawning helper app.
 
+    app.drop_root():            kill helper app and drop root privileges
+
 
 When properly installed, the on-disk layout of an app managed by esky looks
 like this:

esky/__init__.py

@@ -86,6 +86,8 @@
 
     app.get_root():             escalate to root privs by spawning helper app.
 
+    app.drop_root():            kill helper app and drop root privileges
+
 
 When properly installed, the on-disk layout of an app managed by esky looks
 like this:
@@ -328,6 +330,12 @@ def get_root(self):
         if not self.sudo_proxy.has_root():
             raise OSError(None,"could not escalate to root privileges")
 
+    def drop_root(self):
+        """Drop root privileges by killing the helper app."""
+        if self.sudo_proxy is not None:
+            self.sudo_proxy.close()
+            self.sudo_proxy = None
+
     @allow_from_sudo()
     def cleanup(self):
         """Perform cleanup tasks in the app directory.

esky/sudo/sudo_unix.py

@@ -95,8 +95,12 @@ def close(self):
             self.wfd = None
             if os.path.isfile(self.wnm):
                 os.unlink(self.wnm)
-            if not os.listdir(self.tdir):
-                os.rmdir(self.tdir)
+            try:
+                if not os.listdir(self.tdir):
+                    os.rmdir(self.tdir)
+            except EnvironmentError, e:
+                if e.errno != errno.ENOENT:
+                    raise
         super(SecureStringPipe,self).close()
 
 
@@ -126,7 +130,7 @@ def spawn_sudo(proxy):
     exe = exe + [b64encode(pickle.dumps(proxy,HIGHEST_PROTOCOL))]
     # Look for a variety of sudo-like programs
     sudo = None
-    display_name = "%s updater" % (proxy.name,)
+    display_name = "%s update" % (proxy.name,)
     if "DISPLAY" in os.environ:
         sudo = find_exe("gksudo","-k","-D",display_name,"--")
         if sudo is None:

esky/tests/eskytester/script1.py

@@ -68,9 +68,13 @@ def cleanup():
 
 #  Upgrade to the next version (0.2, even though 0.3 is available)
 if os.environ.get("ESKY_NEEDSROOT",""):
-    print "GETTING ROOT"
+    already_root = app.has_root()
     app.get_root()
-    print "GOT ROOT"
+    assert app.has_root()
+    app.drop_root()
+    assert app.has_root() == already_root
+    app.get_root()
+
 
 app.install_version("0.2")
 app.reinitialize()