Split DiskDevice constructor in 2 parts

In the constructor only variable initialization is performed. This is
needed because the constructor is executed before the DiskDevice
instance is appended to the device list, and if something fails there,
then the resources may be cleaned up in an incorrect order.

diff --git a/image_creator/disk.py b/image_creator/disk.py
index 809a1a3..4ca3fd2 100644 (file)
--- a/image_creator/disk.py
+++ b/image_creator/disk.py
@@ -10,6 +10,7 @@ import uuid
 import re
 import sys
 import guestfs
+import time
 
 
 class DiskError(Exception):
@@ -78,6 +79,7 @@ class Disk(object):
         # Take a snapshot and return it to the user
         size = blockdev('--getsize', sourcedev)
         cowfd, cow = tempfile.mkstemp()
+        os.close(cowfd)
         self._add_cleanup(os.unlink, cow)
         # Create 1G cow sparse file
         dd('if=/dev/null', 'of=%s' % cow, 'bs=1k', 'seek=%d' % (1024 * 1024))
@@ -92,9 +94,9 @@ class Disk(object):
             self._add_cleanup(dmsetup, 'remove', snapshot)
         finally:
             os.unlink(table)
-
         new_device = DiskDevice("/dev/mapper/%s" % snapshot)
         self._devices.append(new_device)
+        new_device.enable()
         return new_device
 
     def destroy_device(self, device):
@@ -105,9 +107,9 @@ class Disk(object):
         device.destroy()
 
 
-def progress_generator(total):
+def progress_generator(label=''):
     position = 0;
-    for i in progress.bar(range(total)):
+    for i in progress.bar(range(100),''):
         if i < position:
             continue
         position = yield
@@ -121,19 +123,31 @@ class DiskDevice(object):
 
     def __init__(self, device, bootable=True):
         """Create a new DiskDevice."""
+
         self.device = device
         self.bootable = bootable
         self.progress_bar = None
 
         self.g = guestfs.GuestFS()
-        self.g.add_drive_opts(device, readonly=0)
+        self.g.add_drive_opts(self.device, readonly=0)
 
         #self.g.set_trace(1)
         #self.g.set_verbose(1)
 
+        self.guestfs_enabled = False
+    
+    def enable(self):
+        """Enable a newly created DiskDevice"""
+
+        self.progressbar = progress_generator()
+        self.progressbar.next()
         eh = self.g.set_event_callback(self.progress_callback, guestfs.EVENT_PROGRESS)
         self.g.launch()
+        self.guestfs_enabled = True
         self.g.delete_event_callback(eh)
+        if self.progressbar is not None:
+            self.progressbar.send(100)
+            self.progressbar = None
         
         roots = self.g.inspect_os()
         if len(roots) == 0:
@@ -147,20 +161,21 @@ class DiskDevice(object):
 
     def destroy(self):
         """Destroy this DiskDevice instance."""
-        self.g.umount_all()
-        self.g.sync()
-        # Close the guestfs handler
+
+        if self.guestfs_enabled:
+            self.g.umount_all()
+            self.g.sync()
+
+        # Close the guestfs handler if open
         self.g.close()
 
     def progress_callback(self, ev, eh, buf, array):
         position = array[2]
         total = array[3]
-        
-        if self.progress_bar is None:
-            self.progress_bar = progress_generator(total)
-            self.progress_bar.next()
 
-        self.progress_bar.send(position)
+        assert self.progress_bar is not None
+
+        self.progress_bar.send((position * 100)//total)
 
         if position == total:
             self.progress_bar = None