# 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 random
import struct
# project
from kiwi.storage.device_provider import DeviceProvider
[docs]
class SystemIdentifier:
"""
**Create a random ID to identify the system**
The information is used to create the mbrid file as an example
:param str image_id: hex identifier string
"""
def __init__(self):
self.image_id = None
[docs]
def get_id(self) -> str:
"""
Current hex identifier
:return: hex id
:rtype: str
"""
return self.image_id
[docs]
def calculate_id(self) -> None:
"""
Calculate random hex id
Using 4 tuples of rand in range from 1..0xfe
"""
self.image_id = '0x%02x%02x%02x%02x' % (
self._rand(), self._rand(), self._rand(), self._rand()
)
[docs]
def write(self, filename: str) -> None:
"""
Write current hex identifier to file
:param str filename: file path name
"""
with open(filename, 'w') as identifier:
identifier.write('%s\n' % self.image_id)
[docs]
def write_to_disk(self, device_provider: DeviceProvider) -> None:
"""
Write current hex identifier to MBR at offset 0x1b8 on disk
:param object device_provider: Instance based on DeviceProvider
"""
if self.image_id:
packed_id = struct.pack('<I', int(self.image_id, 16))
with open(device_provider.get_device(), 'wb') as disk:
disk.seek(440, 0)
disk.write(packed_id)
def _rand(self):
return random.randrange(1, 0xfe)