rwcal/plugins/vala/rwcal_cloudsim/rift/rwcal/cloudsim/image.py

   1
   2 #
   3 #   Copyright 2016 RIFT.IO Inc
   4 #
   5 #   Licensed under the Apache License, Version 2.0 (the "License");
   6 #   you may not use this file except in compliance with the License.
   7 #   You may obtain a copy of the License at
   8 #
   9 #       http://www.apache.org/licenses/LICENSE-2.0
  10 #
  11 #   Unless required by applicable law or agreed to in writing, software
  12 #   distributed under the License is distributed on an "AS IS" BASIS,
  13 #   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  14 #   See the License for the specific language governing permissions and
  15 #   limitations under the License.
  16 #
  17
  18 import math
  19 import re
  20
  21 from . import shell
  22
  23
  24 class ImageInfoError(Exception):
  25     pass
  26
  27
  28 def qcow2_virtual_size_mbytes(qcow2_filepath):
  29     info_output = shell.command("qemu-img info {}".format(qcow2_filepath))
  30     for line in info_output:
  31         if line.startswith("virtual size"):
  32             match = re.search("\(([0-9]*) bytes\)", line)
  33             if match is None:
  34                 raise ImageInfoError("Could not parse image size")
  35
  36             num_bytes = int(match.group(1))
  37             num_mbytes = num_bytes / 1024 / 1024
  38             return math.ceil(num_mbytes)
  39
  40     raise ImageInfoError("Could not image virtual size field in output")