import os
import re
-import parted
import uuid
+import tempfile
+from collections import namedtuple
+
+import parted
from image_creator.util import get_command
from image_creator.util import FatalError
findfs = get_command('findfs')
truncate = get_command('truncate')
dd = get_command('dd')
+dmsetup = get_command('dmsetup')
-def get_root_partition():
- if not os.path.isfile('/etc/fstab'):
- raise FatalError("Unable to open `/etc/fstab'. File is missing.")
- with open('/etc/fstab') as fstab:
- for line in iter(fstab):
- entry = line.split('#')[0].strip().split()
- if len(entry) != 6:
- continue
+class BundleVolume():
+ _FileSystemEntry = namedtuple('FileSystemEntry',
+ 'dev mpoint fs opts freq passno')
+
+ _Partition = namedtuple('Partition', 'num start end type fs mopts')
+
+ def __init__(self, out, meta):
+ self.out = out
+ self.meta = meta
+
+ self.out.output('Searching for root device ...', False)
+ root = self._get_root_partition()
+
+ if root.startswith("UUID=") or root.startswith("LABEL="):
+ self.root = findfs(root).stdout.strip()
+ else:
+ self.root = root
+
+ if not re.match('/dev/[hsv]d[a-z][1-9]*$', self.root):
+ raise FatalError("Don't know how to handle root device: %s" % \
+ self.root)
+
+ self.disk = re.split('[0-9]', self.root)[0]
- if entry[1] == "/":
- return entry[0]
+ out.success('%s' % self.root)
+
+ def _read_fstable(self, f):
+ if not os.path.isfile(f):
+ raise FatalError("Unable to open: `%s'. File is missing." % f)
+
+ with open(f) as table:
+ for line in iter(table):
+ entry = line.split('#')[0].strip().split()
+ if len(entry) != 6:
+ continue
+ yield self._FileSystemEntry(*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 _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
+
+ def _create_partition_table(self, src_disk, dest_file):
+
+ if src_disk.type != 'msdos':
+ raise FatalError('Only msdos partition tables are supported')
+
+ first_sector = src_disk.getPrimaryPartitions()[0].geometry.start
- return False
+ # 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 = src_disk.getPrimaryPartitions()[0].geometry.start
+ dd('if=%s' % src_disk.device.path, 'of=%s' % dest_file,
+ 'bs=%d' % src_disk.device.sectorSize,
+ 'count=%d' % first_sector, 'conv=notrunc')
-def part_to_dev(part):
- return re.split('[0-9]', part)[0]
+ # Create the Extended boot records (EBRs) in the image
+ extended = src_disk.getExtendedPartition()
+ if not extended:
+ return
-def part_to_num(part):
- return re.split('[^0-9]+', part)[-1]
+ # Extended boot records precede the logical partitions they describe
+ logical = src_disk.getLogicalPartitions()
+ start = extended.geometry.start
+ for i in range(len(logical)):
+ end = logical[i].geometry.start - 1
+ dd('if=%s' % src_disk.device.path, 'of=%s' % dest_file,
+ 'count=%d' % (end - start + 1), 'conv=notrunc',
+ 'seek=%d' % start, 'skip=%d' % start)
+ start = logical[i].geometry.end + 1
-def bundle_volume(out):
+ def _shrink_partitions(self, src_disk, image_file):
- if mnt_mounted():
- raise FatalError('The directory /mnt where the image will be hosted'
- 'is mounted. Please unmount it and start over again.')
+ partitions = []
+ new_end = 0
- out.output('Searching for root device...', False)
- root_part = get_root_partition()
+ image_dev = parted.Device(image_file)
+ image_disk = parted.Disk(image_dev)
- 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)
+ is_extended = lambda p: p.type == parted.PARTITION_EXTENDED
+ is_logical = lambda p: p.type == parted.PARTITION_LOGICAL
- 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)
+ partitions = []
+ for p in src_disk.partitions:
+ g = p.geometry
+ f = p.fileSystem
+ partitions.append(self._Partition(p.number, g.start, g.end,
+ p.type, f.type if f is not None else '',
+ self._mount_options(p.path)))
- device = parted.Device(part_to_dev(root_part))
+ last = partitions[-1]
+ new_end = src_disk.device.getLength()
+ if last.fs == 'linux-swap(v1)':
+ MB = 2 ** 20
+ size = (last.end - last.start + 1) * src_disk.device.sectorSize
+ self.meta['SWAP'] = "%d:%s" % (last.num, (size + MB - 1) // MB)
- image = '/mnt/%s.diskdump' % uuid.uuid4().hex
+ image_disk.deletePartition(
+ image_disk.getPartitionBySector(last.start))
+ image_disk.commit()
- # Create sparse file to host the image
- truncate("-s", "%d" % (device.getLength() * device.sectorSize), image)
+ if is_logical(last) and last.num == 5:
+ extended = image_disk.getExtendedPartition()
+ image_disk.deletePartition(extended)
+ image_disk.commit()
+ partitions.remove(filter(is_extended, partitions)[0])
- disk = parted.Disk(device)
- if disk.type != 'msdos':
- raise FatalError('For now we can only handle msdos partition tables')
+ partitions.remove(last)
+ last = partitions[-1]
- # 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
+ # Leave 2048 blocks at the end
+ new_end = last.end + 2048
- dd('if=%s' % device.path, 'of=%s' % image, 'bs=%d' % device.sectorSize,
- 'count=%d' % first_sector, 'conv=notrunc')
+ if last.mopts.mpoint:
+ stat = os.statvfs(last.mopts.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) // src_disk.device.sectorSize
- return image
+ # Add 10% just to be on the safe side
+ part_end = last.start + (new_size * 11) // 10
+ # Alighn to 2048
+ part_end = ((part_end + 2047) // 2048) * 2048
+ last = last._replace(end=part_end)
+ partitions[-1] = last
+
+ # Leave 2048 blocks at the end.
+ new_end = new_size + 2048
+
+ image_disk.setPartitionGeometry(
+ image_disk.getPartitionBySector(last.start),
+ parted.Constraint(device=image_disk.device),
+ start=last.start, end=last.end)
+ image_disk.commit()
+
+ if last.type == parted.PARTITION_LOGICAL:
+ # Fix the extended partition
+ extended = disk.getExtendedPartition()
+
+ image_disk.setPartitionGeometry(extended,
+ parted.Constraint(device=img_dev),
+ ext.geometry.start, end=last.end)
+ image_disk.commit()
+
+ # Check if the available space is enough to host the image
+ location = os.path.dirname(image_file)
+ size = (new_end + 1) * src_disk.device.sectorSize
+ self.out.output("Examining available space in %s..." % location, False)
+ stat = os.statvfs(location)
+ available = stat.f_bavail * stat.f_frsize
+ if available <= size:
+ raise FatalError('Not enough space in %s to host the image' % \
+ location)
+ self.out.success("sufficient")
+
+ return partitions
+
+ def _fill_partitions(self, src_disk, image, partitions):
+ pass
+
+ def create_image(self):
+
+ image_file = '/mnt/%s.diskdump' % uuid.uuid4().hex
+
+ src_dev = parted.Device(self.disk)
+
+ size = src_dev.getLength() * src_dev.sectorSize
+
+ # Create sparse file to host the image
+ truncate("-s", "%d" % size, image_file)
+
+ src_disk = parted.Disk(src_dev)
+ self._create_partition_table(src_disk, image_file)
+ partitions = self._shrink_partitions(src_disk, image_file)
+ self._fill_partitions(src_disk, image_file, partitions)
+
+ return image_file
+
+# unmounted = filter(lambda p: not p.mopts.mpoint, partitions)
+# mounted = filter(lambda p: p.mopts.mpoint, partitions)
+#
+# for p in unmounted:
+# dd('if=%s' % src_dev.path, 'of=%s' % img_dev.path,
+# 'count=%d' % (p.end - p.start + 1), 'conv=notrunc',
+# 'seek=%d' % p.start, 'skip=%d' % p.start)
+#
+# partition_devices = create_devices(dest, partitions)
+#
+# mounted.sort(key=lambda p: p.mopts.mpoint)
+#
+# return img
# vim: set sta sts=4 shiftwidth=4 sw=4 et ai :
projects / snf-image-creator / blobdiff