Source code for kiwi.storage.subformat.vhdfixed

# Copyright (c) 2015 SUSE Linux GmbH.  All rights reserved.
#
# This file is part of kiwi.
#
# kiwi is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# kiwi is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with kiwi.  If not, see <http://www.gnu.org/licenses/>
#
import struct
from binascii import unhexlify
import re

# project
from kiwi.storage.subformat.base import DiskFormatBase
from kiwi.command import Command

from kiwi.exceptions import (
    KiwiVhdTagError
)


[docs]class DiskFormatVhdFixed(DiskFormatBase): """ **Create vhd image format in fixed subformat** """
[docs] def post_init(self, custom_args): """ vhd disk format post initialization method Store qemu options as list from custom args dict Extract disk tag from custom args :param dict custom_args: custom vhdfixed and qemu argument dictionary .. code:: python {'--tag': 'billing_code', '--qemu-opt': 'value'} """ self.image_format = 'vhdfixed' self.tag = None if '--tag' in custom_args: self.tag = custom_args['--tag'] del custom_args['--tag'] self.options = self.get_qemu_option_list(custom_args) self.options.append('-o') self.options.append('subformat=fixed')
[docs] def create_image_format(self): """ Create vhd fixed disk format """ Command.run( [ 'qemu-img', 'convert', '-f', 'raw', self.diskname, '-O', 'vpc' ] + self.options + [ self.get_target_file_path_for_format(self.image_format) ] ) if self.tag: self._write_vhd_tag(self.tag)
[docs] def store_to_result(self, result): """ Store result file of the vhdfixed format conversion into the provided result instance. In this case compressing the result is preferred as vhdfixed is not a compressed or dynamic format. :param object result: Instance of Result """ result.add( key='disk_format_image', filename=self.get_target_file_path_for_format( self.image_format ), use_for_bundle=True, compress=self.runtime_config.get_bundle_compression( default=True ), shasum=True )
def _pack_net_guid_tag(self, tag): """ Pack tag format into 16 byte binary representation. String format of the tag is: XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX :param string tag: tagname """ tag_format = re.match( ''.join( [ '^', '([0-9a-f]{8})', '-', '([0-9a-f]{4})', '-', '([0-9a-f]{4})', '-', '([0-9a-f]{4})', '-', '([0-9a-f]{12})', '$' ] ), tag ) if not tag_format: raise KiwiVhdTagError( 'disk tag %s does not match format' % tag ) # pack first nibble into 4 byte unsigned long type binary_tag_part_1 = struct.pack( 'I', list(struct.unpack('>L', unhexlify(tag_format.group(1))))[0] ) # pack second nibble into 2 byte unsigned short type binary_tag_part_2 = struct.pack( 'H', list(struct.unpack('>H', unhexlify(tag_format.group(2))))[0] ) # pack third nibble into 2 byte unsigned short type binary_tag_part_3 = struct.pack( 'H', list(struct.unpack('>H', unhexlify(tag_format.group(3))))[0] ) # pack fourth nibble into hex binary_tag_part_4 = unhexlify(tag_format.group(4)) # pack fifth nibble into hex binary_tag_part_5 = unhexlify(tag_format.group(5)) return binary_tag_part_1 + binary_tag_part_2 + \ binary_tag_part_3 + binary_tag_part_4 + \ binary_tag_part_5 def _write_vhd_tag(self, tag): """ Azure service uses a tag injected into the disk image to identify the OS. The tag is 512B long, starting with a GUID, and is placed at a 64K offset from the start of the disk image. +------------------------------+ | jump | GUID(16B)000... | +------------------------------| | 64K offset | TAG (512B) | +------------+-----------------+ """ binary_tag = self._pack_net_guid_tag(tag) vhd_fixed_image = self.get_target_file_path_for_format('vhdfixed') # seek to 64k offset and zero out 512 byte with open(vhd_fixed_image, 'r+b') as vhd_fixed: with open('/dev/zero', 'rb') as null: vhd_fixed.seek(65536, 0) vhd_fixed.write(null.read(512)) vhd_fixed.seek(0, 2) # seek to 64k offset and write tag with open(vhd_fixed_image, 'r+b') as vhd_fixed: vhd_fixed.seek(65536, 0) vhd_fixed.write(binary_tag) vhd_fixed.seek(0, 2)