import os
import re
-import parted
+import tempfile
import uuid
+from collections import namedtuple
+
+import parted
+from image_creator.rsync import Rsync
from image_creator.util import get_command
from image_creator.util import FatalError
+from image_creator.util import try_fail_repeat
+from image_creator.util import free_space
+from image_creator.gpt import GPTPartitionTable
findfs = get_command('findfs')
-truncate = get_command('truncate')
dd = get_command('dd')
+dmsetup = get_command('dmsetup')
+losetup = get_command('losetup')
+mount = get_command('mount')
+umount = get_command('umount')
+blkid = get_command('blkid')
-def get_root_partition():
- if not os.path.isfile('/etc/fstab'):
- raise FatalError("Unable to open `/etc/fstab'. File is missing.")
+MKFS_OPTS = {'ext2': ['-F'],
+ 'ext3': ['-F'],
+ 'ext4': ['-F'],
+ 'reiserfs': ['-ff'],
+ 'btrfs': [],
+ 'minix': [],
+ 'xfs': ['-f'],
+ 'jfs': ['-f'],
+ 'ntfs': ['-F'],
+ 'msdos': [],
+ 'vfat': []}
- with open('/etc/fstab') as fstab:
- for line in iter(fstab):
- entry = line.split('#')[0].strip().split()
- if len(entry) != 6:
- continue
- if entry[1] == "/":
- return entry[0]
+class BundleVolume(object):
+ """This class can be used to create an image out of the running system"""
+
+ def __init__(self, out, meta, tmp=None):
+ """Create an instance of the BundleVolume class."""
+ self.out = out
+ self.meta = meta
+ self.tmp = tmp
+
+ self.out.output('Searching for root device ...', False)
+ root = self._get_root_partition()
+
+ if root.startswith("UUID=") or root.startswith("LABEL="):
+ root = findfs(root).stdout.strip()
+
+ if not re.match('/dev/[hsv]d[a-z][1-9]*$', root):
+ raise FatalError("Don't know how to handle root device: %s" % root)
+
+ out.success(root)
+
+ disk_file = re.split('[0-9]', root)[0]
+ device = parted.Device(disk_file)
+ self.disk = parted.Disk(device)
+
+ def _read_fstable(self, f):
+
+ if not os.path.isfile(f):
+ raise FatalError("Unable to open: `%s'. File is missing." % f)
+
+ FileSystemTableEntry = namedtuple('FileSystemTableEntry',
+ 'dev mpoint fs opts freq passno')
+ with open(f) as table:
+ for line in iter(table):
+ entry = line.split('#')[0].strip().split()
+ if len(entry) != 6:
+ continue
+ yield FileSystemTableEntry(*entry)
+
+ def _get_root_partition(self):
+ for entry in self._read_fstable('/etc/fstab'):
+ if entry.mpoint == '/':
+ return entry.dev
raise FatalError("Unable to find root device in /etc/fstab")
-def mnt_mounted():
- if not os.path.isfile('/etc/mtab'):
- raise FatalError("Unable to open `/etc/fstab'. File is missing.")
+ def _is_mpoint(self, path):
+ for entry in self._read_fstable('/proc/mounts'):
+ if entry.mpoint == path:
+ return True
+ return False
- with open('/etc/mtab') as mtab:
- for line in iter(mtab):
- entry = line.split('#')[0].strip().split()
- if len(entry) != 6:
+ def _get_mount_options(self, device):
+ for entry in self._read_fstable('/proc/mounts'):
+ if not entry.dev.startswith('/'):
continue
- if entry[1] == '/mnt':
- return True
+ if os.path.realpath(entry.dev) == os.path.realpath(device):
+ return entry
+
+ return None
+
+ def _create_partition_table(self, image):
+
+ # Copy the MBR and the space between the MBR and the first partition.
+ # In msdos partition tables Grub Stage 1.5 is located there.
+ # In gpt partition tables the Primary GPT Header is there.
+ first_sector = self.disk.getPrimaryPartitions()[0].geometry.start
+
+ dd('if=%s' % self.disk.device.path, 'of=%s' % image,
+ 'bs=%d' % self.disk.device.sectorSize,
+ 'count=%d' % first_sector, 'conv=notrunc')
+
+ if self.disk.type == 'gpt':
+ # Copy the Secondary GPT Header
+ table = GPTPartitionTable(self.disk.device.path)
+ dd('if=%s' % self.disk.device.path, 'of=%s' % image,
+ 'bs=%d' % self.disk.device.sectorSize, 'conv=notrunc',
+ 'seek=%d' % table.primary.last_usable_lba,
+ 'skip=%d' % table.primary.last_usable_lba)
+
+ # Create the Extended boot records (EBRs) in the image
+ extended = self.disk.getExtendedPartition()
+ if not extended:
+ return
+
+ # Extended boot records precede the logical partitions they describe
+ logical = self.disk.getLogicalPartitions()
+ start = extended.geometry.start
+ for i in range(len(logical)):
+ end = logical[i].geometry.start - 1
+ dd('if=%s' % self.disk.device.path, 'of=%s' % image,
+ 'count=%d' % (end - start + 1), 'conv=notrunc',
+ 'seek=%d' % start, 'skip=%d' % start)
+ start = logical[i].geometry.end + 1
+
+ def _get_partitions(self, disk):
+ Partition = namedtuple('Partition', 'num start end type fs')
+
+ partitions = []
+ for p in disk.partitions:
+ num = p.number
+ start = p.geometry.start
+ end = p.geometry.end
+ ptype = p.type
+ fs = p.fileSystem.type if p.fileSystem is not None else ''
+ partitions.append(Partition(num, start, end, ptype, fs))
+
+ return partitions
+
+ def _shrink_partitions(self, image):
+
+ new_end = self.disk.device.length
+
+ image_disk = parted.Disk(parted.Device(image))
+
+ is_extended = lambda p: p.type == parted.PARTITION_EXTENDED
+ is_logical = lambda p: p.type == parted.PARTITION_LOGICAL
+
+ partitions = self._get_partitions(self.disk)
+
+ last = partitions[-1]
+ if last.fs == 'linux-swap(v1)':
+ MB = 2 ** 20
+ size = (last.end - last.start + 1) * self.disk.device.sectorSize
+ self.meta['SWAP'] = "%d:%s" % (last.num, (size + MB - 1) // MB)
+
+ image_disk.deletePartition(
+ image_disk.getPartitionBySector(last.start))
+ image_disk.commitToDevice()
+
+ if is_logical(last) and last.num == 5:
+ extended = image_disk.getExtendedPartition()
+ image_disk.deletePartition(extended)
+ image_disk.commitToDevice()
+ partitions.remove(filter(is_extended, partitions)[0])
+
+ partitions.remove(last)
+ last = partitions[-1]
+
+ new_end = last.end
+
+ mount_options = self._get_mount_options(
+ self.disk.getPartitionBySector(last.start).path)
+ if mount_options is not None:
+ stat = os.statvfs(mount_options.mpoint)
+ # Shrink the last partition. The new size should be the size of the
+ # occupied blocks
+ blcks = stat.f_blocks - stat.f_bavail
+ new_size = (blcks * stat.f_frsize) // self.disk.device.sectorSize
+
+ # Add 10% just to be on the safe side
+ part_end = last.start + (new_size * 11) // 10
+ # Align to 2048
+ part_end = ((part_end + 2047) // 2048) * 2048
+
+ # Make sure the partition starts where the old partition started.
+ constraint = parted.Constraint(device=image_disk.device)
+ constraint.startRange = parted.Geometry(device=image_disk.device,
+ start=last.start, length=1)
+
+ image_disk.setPartitionGeometry(
+ image_disk.getPartitionBySector(last.start), constraint,
+ start=last.start, end=part_end)
+ image_disk.commitToDevice()
+
+ # Parted may have changed this for better alignment
+ part_end = image_disk.getPartitionBySector(last.start).geometry.end
+ last = last._replace(end=part_end)
+ partitions[-1] = last
+
+ new_end = part_end
+
+ if last.type == parted.PARTITION_LOGICAL:
+ # Fix the extended partition
+ image_disk.minimizeExtendedPartition()
+
+ return (new_end, self._get_partitions(image_disk))
+
+ def _map_partition(self, dev, num, start, end):
+ name = os.path.basename(dev) + "_" + uuid.uuid4().hex
+ tablefd, table = tempfile.mkstemp()
+ try:
+ size = end - start + 1
+ os.write(tablefd, "0 %d linear %s %d" % (size, dev, start))
+ dmsetup('create', "%sp%d" % (name, num), table)
+ finally:
+ os.unlink(table)
+
+ return "/dev/mapper/%sp%d" % (name, num)
+
+ def _unmap_partition(self, dev):
+ if not os.path.exists(dev):
+ return
+
+ try_fail_repeat(dmsetup, 'remove', dev.split('/dev/mapper/')[1])
+
+ def _mount(self, target, devs):
+
+ devs.sort(key=lambda d: d[1])
+ for dev, mpoint in devs:
+ absmpoint = os.path.abspath(target + mpoint)
+ if not os.path.exists(absmpoint):
+ os.makedirs(absmpoint)
+ mount(dev, absmpoint)
+
+ def _umount_all(self, target):
+ mpoints = []
+ for entry in self._read_fstable('/proc/mounts'):
+ if entry.mpoint.startswith(os.path.abspath(target)):
+ mpoints.append(entry.mpoint)
+
+ mpoints.sort()
+ for mpoint in reversed(mpoints):
+ try_fail_repeat(umount, mpoint)
+
+ def _to_exclude(self):
+ excluded = ['/tmp', '/var/tmp']
+ if self.tmp is not None:
+ excluded.append(self.tmp)
+ local_filesystems = MKFS_OPTS.keys() + ['rootfs']
+ for entry in self._read_fstable('/proc/mounts'):
+ if entry.fs in local_filesystems:
+ continue
+
+ mpoint = entry.mpoint
+ if mpoint in excluded:
+ continue
+
+ descendants = filter(
+ lambda p: p.startswith(mpoint + '/'), excluded)
+ if len(descendants):
+ for d in descendants:
+ excluded.remove(d)
+ excluded.append(mpoint)
+ continue
+
+ dirname = mpoint
+ basename = ''
+ found_ancestor = False
+ while dirname != '/':
+ (dirname, basename) = os.path.split(dirname)
+ if dirname in excluded:
+ found_ancestor = True
+ break
+
+ if not found_ancestor:
+ excluded.append(mpoint)
+
+ return excluded
+
+ def _replace_uuids(self, target, new_uuid):
+
+ files = ['/etc/fstab',
+ '/boot/grub/grub.cfg',
+ '/boot/grub/menu.lst',
+ '/boot/grub/grub.conf']
+
+ orig = {}
+ for p in self.disk.partitions:
+ if p.number in new_uuid.keys():
+ orig[p.number] = \
+ blkid('-s', 'UUID', '-o', 'value', p.path).stdout.strip()
+
+ for f in map(lambda f: target + f, files):
+ if not os.path.exists(f):
+ continue
+
+ with open(f, 'r') as src:
+ lines = src.readlines()
+ with open(f, 'w') as dest:
+ for line in lines:
+ for i, uuid in new_uuid.items():
+ line = re.sub(orig[i], uuid, line)
+ dest.write(line)
+
+ def _create_filesystems(self, image, partitions):
+
+ filesystem = {}
+ for p in self.disk.partitions:
+ filesystem[p.number] = self._get_mount_options(p.path)
+
+ unmounted = filter(lambda p: filesystem[p.num] is None, partitions)
+ mounted = filter(lambda p: filesystem[p.num] is not None, partitions)
+
+ # For partitions that are not mounted right now, we can simply dd them
+ # into the image.
+ for p in unmounted:
+ self.out.output('Cloning partition %d ... ' % p.num, False)
+ dd('if=%s' % self.disk.device.path, 'of=%s' % image,
+ 'count=%d' % (p.end - p.start + 1), 'conv=notrunc',
+ 'seek=%d' % p.start, 'skip=%d' % p.start)
+ self.out.success("done")
+
+ loop = str(losetup('-f', '--show', image)).strip()
+ mapped = {}
+ try:
+ for p in mounted:
+ i = p.num
+ mapped[i] = self._map_partition(loop, i, p.start, p.end)
+
+ new_uuid = {}
+ # Create the file systems
+ for i, dev in mapped.iteritems():
+ fs = filesystem[i].fs
+ self.out.output('Creating %s filesystem on partition %d ... ' %
+ (fs, i), False)
+ get_command('mkfs.%s' % fs)(*(MKFS_OPTS[fs] + [dev]))
+ self.out.success('done')
+ new_uuid[i] = blkid(
+ '-s', 'UUID', '-o', 'value', dev).stdout.strip()
+
+ target = tempfile.mkdtemp()
+ try:
+ absmpoints = self._mount(target,
+ [(mapped[i], filesystem[i].mpoint)
+ for i in mapped.keys()])
+ excluded = self._to_exclude()
- return False
+ rsync = Rsync(self.out)
+ # Excluded paths need to be relative to the source
+ for excl in map(lambda p: p[1:], excluded + [image]):
+ rsync.exclude(excl)
-def part_to_dev(part):
- return re.split('[0-9]', part)[0]
+ rsync.archive().hard_links().xattrs().sparse().acls()
+ rsync.run('/', target, 'host', 'temporary image')
-def part_to_num(part):
- return re.split('[^0-9]+', part)[-1]
+ # Create missing mountpoints. Since they are mountpoints, we
+ # cannot determine the ownership and the mode of the real
+ # directory. Make them inherit those properties from their
+ # parent dir
+ for excl in excluded:
+ dirname = os.path.dirname(excl)
+ stat = os.stat(dirname)
+ os.mkdir(target + excl)
+ os.chmod(target + excl, stat.st_mode)
+ os.chown(target + excl, stat.st_uid, stat.st_gid)
-def bundle_volume(out):
+ # /tmp and /var/tmp are special cases. We exclude then even if
+ # they aren't mountpoints. Restore their permissions.
+ for excl in ('/tmp', '/var/tmp'):
+ if self._is_mpoint(excl):
+ os.chmod(target + excl, 041777)
+ os.chown(target + excl, 0, 0)
+ else:
+ stat = os.stat(excl)
+ os.chmod(target + excl, stat.st_mode)
+ os.chown(target + excl, stat.st_uid, stat.st_gid)
- if mnt_mounted():
- raise FatalError('The directory /mnt where the image will be hosted'
- 'is mounted. Please unmount it and start over again.')
+ # We need to replace the old UUID referencies with the new
+ # ones in grub configuration files and /etc/fstab for file
+ # systems that have been recreated.
+ self._replace_uuids(target, new_uuid)
- out.output('Searching for root device...', False)
- root_part = get_root_partition()
+ finally:
+ self._umount_all(target)
+ os.rmdir(target)
+ finally:
+ for dev in mapped.values():
+ self._unmap_partition(dev)
+ losetup('-d', loop)
- if root_part.startswith("UUID=") or root_part.startswith("LABEL="):
- root_part = findfs(root_part)
- elif not root_part.startswith("/"):
- raise FatalError("Unable to find a block device for: %s" % root_dev)
+ def create_image(self, image):
+ """Given an image filename, this method will create an image out of the
+ running system.
+ """
- if not re.match('/dev/[hsv]d[a-z][1-9]*$', root_part):
- raise FatalError("Don't know how to handle root device: %s" % root_dev)
+ size = self.disk.device.length * self.disk.device.sectorSize
- device = parted.Device(part_to_dev(root_part))
+ # Create sparse file to host the image
+ fd = os.open(image, os.O_WRONLY | os.O_CREAT)
+ try:
+ os.ftruncate(fd, size)
+ finally:
+ os.close(fd)
- image = '/mnt/%s.diskdump' % uuid.uuid4().hex
+ self._create_partition_table(image)
+ end_sector, partitions = self._shrink_partitions(image)
- # Create sparse file to host the image
- truncate("-s", "%d" % (device.getLength() * device.sectorSize), image)
+ if self.disk.type == 'gpt':
+ old_size = size
+ size = (end_sector + 1) * self.disk.device.sectorSize
+ ptable = GPTPartitionTable(image)
+ size = ptable.shrink(size, old_size)
+ else:
+ # Alighn to 2048
+ end_sector = ((end_sector + 2047) // 2048) * 2048
+ size = (end_sector + 1) * self.disk.device.sectorSize
- disk = parted.Disk(device)
- if disk.type != 'msdos':
- raise FatalError('For now we can only handle msdos partition tables')
+ # Truncate image to the new size.
+ fd = os.open(image, os.O_RDWR)
+ try:
+ os.ftruncate(fd, size)
+ finally:
+ os.close(fd)
- # Copy the MBR and the space between the MBR and the first partition.
- # In Grub version 1 Stage 1.5 is located there.
- first_sector = disk.getPrimaryPartitions()[0].geometry.start
+ # Check if the available space is enough to host the image
+ dirname = os.path.dirname(image)
+ self.out.output("Examining available space ...", False)
+ if free_space(dirname) <= size:
+ raise FatalError('Not enough space under %s to host the image' %
+ dirname)
+ self.out.success("sufficient")
- dd('if=%s' % device.path, 'of=%s' % image, 'bs=%d' % device.sectorSize,
- 'count=%d' % first_sector, 'conv=notrunc')
+ self._create_filesystems(image, partitions)
- return image
+ return image
# vim: set sta sts=4 shiftwidth=4 sw=4 et ai :
projects / snf-image-creator / blobdiff