Remove need for shell wrap complexity

client/update_grub.py

@@ -4,7 +4,7 @@ import os
 import re
 import string
 import subprocess
-import sys
+import tempfile
 
 
 class GrubUpdater(object):
@@ -30,9 +30,12 @@ class GrubUpdater(object):
     return match.group('volume_id').decode('ascii')
 
   def Update(self):
+    grub_dir = os.path.join(self._boot_dir, 'grub')
+
+    with tempfile.NamedTemporaryFile(dir=grub_dir, delete=False) as fh:
       current = os.readlink(os.path.join(self._image_dir, 'current'))
 
-    sys.stdout.write("""
+      fh.write("""
 set timeout=5
 set default=%(default_image_filename)s
 """ % {
@@ -46,7 +49,7 @@ set default=%(default_image_filename)s
         files.append(filename)
 
       for i, filename in enumerate(sorted(files, reverse=True)):
-      sys.stdout.write("""
+        fh.write("""
 menuentry "%(image_filename)s (%(volume_id)s)" --hotkey=%(hotkey)s {
   search --no-floppy --file --set=root %(image_path)s/%(image_filename)s
   iso_path="%(image_path)s/%(image_filename)s"
@@ -61,3 +64,6 @@ menuentry "%(image_filename)s (%(volume_id)s)" --hotkey=%(hotkey)s {
           'hotkey': self._HOTKEYS[i],
           'volume_id': self._GetVolumeID(os.path.join(self._image_dir, filename)),
         })
+
+      fh.flush()
+      os.rename(fh.name, os.path.join(grub_dir, 'grub.cfg'))