Change the interface between XendRoot.get_network_script and Vifctl so that a

list is passed rather than a single string.  This expands the config-file
interface so that parameters may be passed to the network scripts from the
config file.

Fix XendRoot._logError (missing asterisk before args parameter).

In XendRoot, allow an empty configuration file.  This makes it easier to unit
test code reliant on XendRoot.

Signed-off-by: Ewan Mellor <ewan@xensource.com>

tools/python/xen/xend/Vifctl.py

@@ -32,4 +32,5 @@ def network(op):
         raise ValueError('Invalid operation: ' + op)
     script = XendRoot.instance().get_network_script()
     if script:
-        os.spawnl(os.P_WAIT, script, script, op)
+        script.insert(1, op)
+        os.spawnv(os.P_WAIT, script[0], script)

tools/python/xen/xend/XendRoot.py

@@ -114,7 +114,7 @@ class XendRoot:
         """
         return self.components.get(name)
 
-    def _logError(self, fmt, args):
+    def _logError(self, fmt, *args):
         """Logging function to log to stderr. We use this for XendRoot log
         messages because they may be logged before the logger has been
         configured.  Other components can safely use the logger.
@@ -144,7 +144,10 @@ class XendRoot:
                     config = sxp.parse(fin)
                 finally:
                     fin.close()
-                config.insert(0, 'xend-config')
+                if config is None:
+                    config = ['xend-config']
+                else:
+                    config.insert(0, 'xend-config')
                 self.config = config
             except Exception, ex:
                 self._logError('Reading config file %s: %s',
@@ -250,7 +253,9 @@ class XendRoot:
         s = self.get_config_value('network-script')
 
         if s:
-            return os.path.join(self.network_script_dir, s)
+            result = s.split(" ")
+            result[0] = os.path.join(self.network_script_dir, result[0])
+            return result
         else:
             return None
 
@@ -258,9 +263,6 @@ class XendRoot:
     def get_enable_dump(self):
         return self.get_config_bool('enable-dump', 'no')
 
-    def get_vif_bridge(self):
-        return self.get_config_value('vif-bridge', 'xenbr0')
-
     def get_vif_script(self):
         return self.get_config_value('vif-script', 'vif-bridge')