# interpreted as representing official policies, either expressed
# or implied, of GRNET S.A.
+import os
+import re
+import parted
+import uuid
+from collections import namedtuple
+
+from image_creator.util import get_command
from image_creator.util import FatalError
-def bundle_volume():
- raise FatalError("Creating an image out of a running system is not yet "
- "supported.")
+findfs = get_command('findfs')
+truncate = get_command('truncate')
+dd = get_command('dd')
+
+MB = 2 ** 20
+
+def fstable(f):
+ if not os.path.isfile(f):
+ raise FatalError("Unable to open: `%s'. File is missing." % f)
+
+ Entry = namedtuple('Entry', '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 Entry(*entry)
+
+
+def get_root_partition():
+ for entry in fstable('/etc/fstab'):
+ if entry.mpoint == '/':
+ return entry.dev
+
+ raise FatalError("Unable to find root device in /etc/fstab")
+
+
+def is_mpoint(path):
+ for entry in fstable('/proc/mounts'):
+ if entry.mpoint == path:
+ return True
+ return False
+
+
+def mpoint(device):
+ for entry in fstable('/proc/mounts'):
+ if not entry.dev.startswith('/'):
+ continue
+
+ if os.path.realpath(entry.dev) == os.path.realpath(device):
+ return entry.mpoint
+
+ return ""
+
+
+def create_EBRs(src, dest):
+
+ # The Extended boot records precede the logical partitions they describe
+ extended = src.getExtendedPartition()
+ if not extended:
+ return
+
+ logical = src.getLogicalPartitions()
+ start = extended.geometry.start
+ for i in range(len(logical)):
+ end = logical[i].geometry.start - 1
+ dd('if=%s' % src.device.path, 'of=%s' % dest,
+ 'count=%d' % (end - start + 1), 'conv=notrunc', 'seek=%d' % start,
+ 'skip=%d' % start)
+ start = logical[i].geometry.end + 1
+
+
+def bundle_volume(out, meta):
+
+ if is_mpoint('/mnt'):
+ raise FatalError('The directory /mnt where the image will be hosted'
+ 'is mounted. Please unmount it and start over again.')
+
+ out.output('Searching for root device...', False)
+ root_part = get_root_partition()
+
+ if root_part.startswith("UUID=") or root_part.startswith("LABEL="):
+ root_part = findfs(root_part).stdout.strip()
+ elif not root_part.startswith("/"):
+ raise FatalError("Unable to find a block device for: %s" % root_dev)
+
+ 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)
+
+ part_to_dev = lambda p: re.split('[0-9]', p)[0]
+
+ root_dev = part_to_dev(root_part)
+
+ out.success('%s' % root_dev)
+
+ src_dev = parted.Device(root_dev)
+
+ img = '/mnt/%s.diskdump' % uuid.uuid4().hex
+ disk_size = src_dev.getLength() * src_dev.sectorSize
+
+ # Create sparse file to host the image
+ truncate("-s", "%d" % disk_size, img)
+
+ src_disk = parted.Disk(src_dev)
+ if src_disk.type != 'msdos':
+ raise FatalError('For now we can only handle msdos partition tables')
+
+ # 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_dev.path, 'of=%s' % img, 'bs=%d' % src_dev.sectorSize,
+ 'count=%d' % first_sector, 'conv=notrunc')
+
+ # Create the Extended boot records (EBRs) in the image
+ create_EBRs(src_disk, img)
+
+ img_dev = parted.Device(img)
+ img_disk = parted.Disk(img_dev)
+
+ is_extended = lambda p: p.type == parted.PARTITION_EXTENDED
+ is_logical = lambda p: p.type == parted.PARTITION_LOGICAL
+
+ Partition = namedtuple('Partition', 'num start end type fs mpoint')
+
+ partitions = []
+ for p in src_disk.partitions:
+ g = p.geometry
+ f = p.fileSystem
+ partitions.append(Partition(p.number, g.start, g.end, p.type,
+ f.type if f is not None else '', mpoint(p.path)))
+
+ last = partitions[-1]
+ new_end = src_dev.getLength()
+ if last.fs == 'linux-swap(v1)':
+ size = (last.end - last.start + 1) * src_dev.sectorSize
+ meta['SWAP'] = "%d:%s" % (last.num, ((size + MB - 1) // MB))
+
+ img_disk.deletePartition(img_disk.getPartitionBySector(last.start))
+ img_disk.commit()
+
+ if is_logical(last) and last.num == 5:
+ img_disk.deletePartition(img_disk.getExtendedPartition())
+ img_disk.commit()
+ partitions.remove(filter(is_extended, partitions)[0])
+
+ partitions.remove(last)
+ last = partitions[-1]
+
+ # Leave 2048 blocks at the end
+ new_end = last.end + 2048
+
+ if last.mpoint:
+ stat = os.statvfs(last.mpoint)
+ occupied_blocks = stat.f_blocks - stat.f_bavail
+ new_size = (occupied_blocks * stat.f_frsize) // src_dev.sectorSize
+
+ # 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
+
+ img_disk.setPartitionGeometry(
+ img_disk.getPartitionBySector(last.start),
+ parted.Constraint(device=img_dev), start=last.start, end=last.end)
+ img_disk.commit()
+
+ if last.type == parted.PARTITION_LOGICAL:
+ # Fix the extended partition
+ ext = disk.getExtendedPartition()
+
+ img_disk.setPartitionGeometry(ext,
+ parted.Constraint(device=img_dev), ext.geometry.start,
+ end=last.end)
+ img_disk.commit()
+
+ # Check if we have the available space on the filesystem hosting /mnt
+ # for the image.
+ out.output("Examining available space in /mnt ... ", False)
+ stat = os.statvfs('/mnt')
+ image_size = (new_end + 1) * src_dev.sectorSize
+ available = stat.f_bavail * stat.f_frsize
+
+ if available <= image_size:
+ raise FatalError('Not enough space in /mnt to host the image')
+
+ out.success("sufficient")
+
+ return img
# vim: set sta sts=4 shiftwidth=4 sw=4 et ai :
projects / snf-image-creator / blobdiff