cloner: clone serial files

Before this, on clone the serial file would remain the same for the cloned
domain. This doesn't make much sense as the output would be an intermix of two
unrelated output sequences.

Here we apply the the same filename changing algorithm, as with disk files.

Signed-off-by: Oleg Vasilev <oleg.vasilev@virtuozzo.com>

virtinst/cloner.py

@@ -9,6 +9,7 @@
 
 import re
 import os
+from itertools import chain
 
 import libvirt
 
@@ -20,6 +21,7 @@ from .devices import DeviceInterface
 from .devices import DeviceDisk
 from .logger import log
 from .devices import DeviceChannel
+from .devices import DeviceSerial
 
 
 def _replace_vm(conn, name):
@@ -70,9 +72,9 @@ def _generate_clone_name(conn, basename):
             sep="", start_num=start_num, force_num=force_num)
 
 
-def _generate_clone_disk_path(conn, origname, newname, origpath):
+def _generate_clone_path(origname, newname, origpath, cb_exists):
     """
-    Generate desired cloned disk path name, derived from the
+    Generate desired cloned path for auxiliary files, derived from the
     original path, original VM name, and proposed new VM name
     """
     if origpath is None:
@@ -99,9 +101,7 @@ def _generate_clone_disk_path(conn, origname, newname, origpath):
         clonebase = newname
 
     clonebase = os.path.join(dirname, clonebase)
-    def cb(p):
-        return DeviceDisk.path_definitely_exists(conn, p)
-    return generatename.generate_name(clonebase, cb, suffix=suffix)
+    return generatename.generate_name(clonebase, cb_exists, suffix=suffix)
 
 
 def _lookup_vm(conn, name):
@@ -287,7 +287,9 @@ class Cloner(object):
 
     @staticmethod
     def generate_clone_disk_path(conn, origname, newname, origpath):
-        return _generate_clone_disk_path(conn, origname, newname, origpath)
+        def cb_exists(p):
+            return DeviceDisk.path_definitely_exists(conn, p)
+        return _generate_clone_path(origname, newname, origpath, cb_exists)
 
     @staticmethod
     def build_clone_disk(orig_disk, clonepath, allow_create, sparse):
@@ -455,6 +457,21 @@ class Cloner(object):
     # Functional methods #
     ######################
 
+    def _prepare_serial_files(self):
+        for serial in chain(self._new_guest.devices.console,
+                            self._new_guest.devices.serial):
+            if serial.type != DeviceSerial.TYPE_FILE:
+                continue
+
+            def cb_exists(path):
+                # Ignore the check for now
+                return False
+
+            serial.source.path = _generate_clone_path(self.src_name,
+                                                      self.new_guest.name,
+                                                      serial.source.path,
+                                                      cb_exists=cb_exists)
+
     def _prepare_nvram(self):
         if not self._nvram_diskinfo:
             return
@@ -534,6 +551,7 @@ class Cloner(object):
             xmldisk.set_source_path(new_disk.get_source_path())
 
         self._prepare_nvram()
+        self._prepare_serial_files()
 
         # Save altered clone xml
         diff = xmlutil.diff(self._src_guest.get_xml(),