866a06f92d
Now that the main partitioning refactor patch is merged, there is a small relict of handling partitions still in the disk-image-create main. This patch moves the functionality from disk-image-create to the block-device/partitioning module: it is mostly a rewrite of the original bash code in python. Change-Id: Ia73baeca74180a7bc9ea487da03ff56d6a3070ce Signed-off-by: Andreas Florath <andreas@florath.net>
255 lines
8.7 KiB
Python
255 lines
8.7 KiB
Python
# Copyright 2016 Andreas Florath (andreas@florath.net)
|
|
#
|
|
# Licensed under the Apache License, Version 2.0 (the "License"); you may
|
|
# not use this file except in compliance with the License. You may obtain
|
|
# a copy of the License at
|
|
#
|
|
# http://www.apache.org/licenses/LICENSE-2.0
|
|
#
|
|
# Unless required by applicable law or agreed to in writing, software
|
|
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
|
|
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
|
|
# License for the specific language governing permissions and limitations
|
|
# under the License.
|
|
|
|
import codecs
|
|
from diskimage_builder.block_device.blockdevicesetupexception \
|
|
import BlockDeviceSetupException
|
|
from diskimage_builder.block_device.level0 import LocalLoop
|
|
from diskimage_builder.block_device.level1 import Partitioning
|
|
from diskimage_builder.graph.digraph import Digraph
|
|
import json
|
|
import logging
|
|
import os
|
|
import shutil
|
|
import sys
|
|
import yaml
|
|
|
|
|
|
logger = logging.getLogger(__name__)
|
|
|
|
|
|
class BlockDevice(object):
|
|
"""Handles block devices.
|
|
|
|
This class handles the complete setup and deletion of all aspects
|
|
of the block device level.
|
|
|
|
A typical call sequence:
|
|
|
|
cmd_create: creates all the different aspects of the block
|
|
device. When this call is successful, the complete block level
|
|
device is set up, filesystems are created and are mounted at
|
|
the correct position.
|
|
After this call it is possible to copy / install all the needed
|
|
files into the appropriate directories.
|
|
|
|
cmd_umount: unmount and detaches all directories and used many
|
|
resources. After this call the used (e.g.) images are still
|
|
available for further handling, e.g. converting from raw in
|
|
some other format.
|
|
|
|
cmd_cleanup: removes everything that was created with the
|
|
'cmd_create' call, i.e. all images files themselves and
|
|
internal temporary configuration.
|
|
|
|
cmd_delete: unmounts and removes everything that was created
|
|
during the 'cmd_create' all. This call should be used in error
|
|
conditions when there is the need to remove all allocated
|
|
resources immediately and as good as possible.
|
|
From the functional point of view this is mostly the same as a
|
|
call to 'cmd_umount' and 'cmd_cleanup' - but is typically more
|
|
error tolerance.
|
|
|
|
In a script this should be called in the following way:
|
|
|
|
dib-block-device --phase=create ...
|
|
trap "dib-block-device --phase=delete ..." EXIT
|
|
# copy / install files
|
|
dib-block-device --phase=umount ...
|
|
# convert image(s)
|
|
dib-block-device --phase=cleanup ...
|
|
trap - EXIT
|
|
"""
|
|
|
|
# Default configuration:
|
|
# one image, one partition, mounted under '/'
|
|
DefaultConfig = """
|
|
- local_loop:
|
|
name: image0
|
|
"""
|
|
|
|
# This is an example of the next level config
|
|
# mkfs:
|
|
# base: root
|
|
# type: ext4
|
|
# mount_point: /
|
|
|
|
# A dictionary to map sensible names to internal implementation.
|
|
cfg_type_map = {
|
|
'local_loop': LocalLoop,
|
|
'partitioning': Partitioning,
|
|
'mkfs': 'not yet implemented',
|
|
}
|
|
|
|
def __init__(self, block_device_config, build_dir,
|
|
default_image_size, default_image_dir):
|
|
logger.debug("Creating BlockDevice object")
|
|
logger.debug("Config given [%s]" % block_device_config)
|
|
logger.debug("Build dir [%s]" % build_dir)
|
|
if block_device_config is None:
|
|
block_device_config = BlockDevice.DefaultConfig
|
|
self.config = yaml.safe_load(block_device_config)
|
|
logger.debug("Using config [%s]" % self.config)
|
|
|
|
self.default_config = {
|
|
'image_size': default_image_size,
|
|
'image_dir': default_image_dir}
|
|
self.state_dir = os.path.join(build_dir,
|
|
"states/block-device")
|
|
self.state_json_file_name \
|
|
= os.path.join(self.state_dir, "state.json")
|
|
|
|
def write_state(self, result):
|
|
logger.debug("Write state [%s]" % self.state_json_file_name)
|
|
os.makedirs(self.state_dir)
|
|
with open(self.state_json_file_name, "w") as fd:
|
|
json.dump([self.config, self.default_config, result], fd)
|
|
|
|
def load_state(self):
|
|
with codecs.open(self.state_json_file_name,
|
|
encoding="utf-8", mode="r") as fd:
|
|
return json.load(fd)
|
|
|
|
def create_graph(self, config, default_config):
|
|
# This is the directed graph of nodes: each parse method must
|
|
# add the appropriate nodes and edges.
|
|
dg = Digraph()
|
|
|
|
for config_entry in config:
|
|
if len(config_entry) != 1:
|
|
logger.error("Invalid config entry: more than one key "
|
|
"on top level [%s]" % config_entry)
|
|
raise BlockDeviceSetupException(
|
|
"Top level config must contain exactly one key per entry")
|
|
logger.debug("Config entry [%s]" % config_entry)
|
|
cfg_obj_name = config_entry.keys()[0]
|
|
cfg_obj_val = config_entry[cfg_obj_name]
|
|
|
|
# As the first step the configured objects are created
|
|
# (if it exists)
|
|
if cfg_obj_name not in BlockDevice.cfg_type_map:
|
|
logger.error("Configured top level element [%s] "
|
|
"does not exists." % cfg_obj_name)
|
|
return 1
|
|
cfg_obj = BlockDevice.cfg_type_map[cfg_obj_name](
|
|
cfg_obj_val, default_config)
|
|
# At this point it is only possible to add the nodes:
|
|
# adding the edges needs all nodes first.
|
|
cfg_obj.insert_nodes(dg)
|
|
|
|
# Now that all the nodes exists: add also the edges
|
|
for node in dg.get_iter_nodes_values():
|
|
node.insert_edges(dg)
|
|
|
|
call_order = dg.topological_sort()
|
|
logger.debug("Call order [%s]" % (list(call_order)))
|
|
return dg, call_order
|
|
|
|
def create(self, result, rollback):
|
|
dg, call_order = self.create_graph(self.config, self.default_config)
|
|
for node in call_order:
|
|
node.create(result, rollback)
|
|
|
|
def cmd_create(self):
|
|
"""Creates the block device"""
|
|
|
|
logger.info("create() called")
|
|
logger.debug("Using config [%s]" % self.config)
|
|
|
|
result = {}
|
|
rollback = []
|
|
|
|
try:
|
|
self.create(result, rollback)
|
|
except BlockDeviceSetupException as bdse:
|
|
logger.error("exception [%s]" % bdse)
|
|
for rollback_cb in reversed(rollback):
|
|
rollback_cb()
|
|
sys.exit(1)
|
|
|
|
# To be compatible with the current implementation, echo the
|
|
# result to stdout.
|
|
# If there is no partition needed, pass back directly the
|
|
# image.
|
|
if 'root' in result:
|
|
print("%s" % result['root']['device'])
|
|
else:
|
|
print("%s" % result['image0']['device'])
|
|
|
|
self.write_state(result)
|
|
|
|
logger.info("create() finished")
|
|
return 0
|
|
|
|
def _load_state(self):
|
|
logger.info("_load_state() called")
|
|
try:
|
|
os.stat(self.state_json_file_name)
|
|
except OSError:
|
|
logger.info("State already cleaned - no way to do anything here")
|
|
return None, None, None
|
|
|
|
config, default_config, state = self.load_state()
|
|
logger.debug("Using config [%s]" % config)
|
|
logger.debug("Using default config [%s]" % default_config)
|
|
logger.debug("Using state [%s]" % state)
|
|
|
|
# Deleting must be done in reverse order
|
|
dg, call_order = self.create_graph(config, default_config)
|
|
reverse_order = reversed(call_order)
|
|
return dg, reverse_order, state
|
|
|
|
def cmd_umount(self):
|
|
"""Unmounts the blockdevice and cleanup resources"""
|
|
|
|
dg, reverse_order, state = self._load_state()
|
|
if dg is None:
|
|
return 0
|
|
for node in reverse_order:
|
|
node.umount(state)
|
|
|
|
# To be compatible with the current implementation, echo the
|
|
# result to stdout.
|
|
print("%s" % state['image0']['image'])
|
|
|
|
return 0
|
|
|
|
def cmd_cleanup(self):
|
|
"""Cleanup all remaining relicts - in good case"""
|
|
|
|
dg, reverse_order, state = self._load_state()
|
|
if dg is None:
|
|
return 0
|
|
for node in reverse_order:
|
|
node.cleanup(state)
|
|
|
|
logger.info("Removing temporary dir [%s]" % self.state_dir)
|
|
shutil.rmtree(self.state_dir)
|
|
|
|
return 0
|
|
|
|
def cmd_delete(self):
|
|
"""Cleanup all remaining relicts - in case of an error"""
|
|
|
|
dg, reverse_order, state = self._load_state()
|
|
if dg is None:
|
|
return 0
|
|
for node in reverse_order:
|
|
node.delete(state)
|
|
|
|
logger.info("Removing temporary dir [%s]" % self.state_dir)
|
|
shutil.rmtree(self.state_dir)
|
|
|
|
return 0
|