Don't check the token if -t is not defined
[snf-image-creator] / image_creator / bundle_volume.py
index ee93fc8..a6fc27a 100644 (file)
 
 import os
 import re
-import uuid
 import tempfile
-import time
+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')
-
-MKFS_OPTS = {
-    'ext2': ['-F'],
-    'ext3': ['-F'],
-    'ext4': ['-F'],
-    'reiserfs': ['-ff'],
-    'btrfs': [],
-    'minix': [],
-    'xfs': ['-f'],
-    'jfs': ['-f'],
-    'ntfs': ['-F'],
-    'msdos': [],
-    'vfat': []
-    }
-
-
-class BundleVolume():
-
-    def __init__(self, out, meta):
+blkid = get_command('blkid')
+
+MKFS_OPTS = {'ext2': ['-F'],
+             'ext3': ['-F'],
+             'ext4': ['-F'],
+             'reiserfs': ['-ff'],
+             'btrfs': [],
+             'minix': [],
+             'xfs': ['-f'],
+             'jfs': ['-f'],
+             'ntfs': ['-F'],
+             'msdos': [],
+             'vfat': []}
+
+
+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()
@@ -92,14 +96,14 @@ class BundleVolume():
         if not os.path.isfile(f):
             raise FatalError("Unable to open: `%s'. File is missing." % f)
 
-        FileSystemEntry = namedtuple('FileSystemEntry',
-                                     'dev mpoint fs opts freq passno')
+        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 FileSystemEntry(*entry)
+                yield FileSystemTableEntry(*entry)
 
     def _get_root_partition(self):
         for entry in self._read_fstable('/etc/fstab'):
@@ -126,17 +130,23 @@ class BundleVolume():
 
     def _create_partition_table(self, image):
 
-        if self.disk.type != 'msdos':
-            raise FatalError('Only msdos partition tables are supported')
-
         # Copy the MBR and the space between the MBR and the first partition.
-        # In Grub version 1 Stage 1.5 is located there.
+        # 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:
@@ -168,10 +178,9 @@ class BundleVolume():
 
     def _shrink_partitions(self, image):
 
-        new_end = self.disk.device.getLength()
+        new_end = self.disk.device.length
 
-        image_dev = parted.Device(image)
-        image_disk = parted.Disk(image_dev)
+        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
@@ -186,23 +195,22 @@ class BundleVolume():
 
             image_disk.deletePartition(
                 image_disk.getPartitionBySector(last.start))
-            image_disk.commit()
+            image_disk.commitToDevice()
 
             if is_logical(last) and last.num == 5:
                 extended = image_disk.getExtendedPartition()
                 image_disk.deletePartition(extended)
-                image_disk.commit()
+                image_disk.commitToDevice()
                 partitions.remove(filter(is_extended, partitions)[0])
 
             partitions.remove(last)
             last = partitions[-1]
 
-            # Leave 2048 blocks at the end
-            new_end = last.end + 2048
+            new_end = last.end
 
         mount_options = self._get_mount_options(
-                self.disk.getPartitionBySector(last.start).path)
-        if mount_options is not None: 
+            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
@@ -211,37 +219,34 @@ class BundleVolume():
 
             # Add 10% just to be on the safe side
             part_end = last.start + (new_size * 11) // 10
-            # Alighn to 2048
+            # 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),
-                parted.Constraint(device=image_disk.device),
-                start=last.start, end=last.end)
-            image_disk.commit()
+                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
 
-            # Leave 2048 blocks at the end.
-            new_end = new_size + 2048
-
+            new_end = part_end
 
             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()
+                image_disk.minimizeExtendedPartition()
 
-        return new_end
+        return (new_end, self._get_partitions(image_disk))
 
     def _map_partition(self, dev, num, start, end):
-        name = os.path.basename(dev)
+        name = os.path.basename(dev) + "_" + uuid.uuid4().hex
         tablefd, table = tempfile.mkstemp()
         try:
             size = end - start + 1
@@ -256,8 +261,7 @@ class BundleVolume():
         if not os.path.exists(dev):
             return
 
-        dmsetup('remove', dev.split('/dev/mapper/')[1])
-        time.sleep(0.1)
+        try_fail_repeat(dmsetup, 'remove', dev.split('/dev/mapper/')[1])
 
     def _mount(self, target, devs):
 
@@ -273,48 +277,149 @@ class BundleVolume():
         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):
-            umount(mpoint)
+            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
 
-    def _create_filesystems(self, image):
-        
-        partitions = self._get_partitions(parted.Disk(parted.Device(image)))
-        filesystems = {}
+            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:
-            filesystems[p.number] = self._get_mount_options(p.path)
+            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
 
-        unmounted = filter(lambda p: filesystems[p.num] is None, partitions)
-        mounted = filter(lambda p: filesystems[p.num] is not None, partitions)
+            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
+                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 = filesystems[i].fs
+                fs = filesystem[i].fs
                 self.out.output('Creating %s filesystem on partition %d ... ' %
-                    (fs, i), False)
+                                (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], filesystems[i].mpoint) for i in mapped.keys()]
-                )
+                                         [(mapped[i], filesystem[i].mpoint)
+                                         for i in mapped.keys()])
+                excluded = self._to_exclude()
+
+                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)
+
+                rsync.archive().hard_links().xattrs().sparse().acls()
+                rsync.run('/', target, 'host', 'temporary image')
+
+                # 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)
+
+                # /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)
+
+                # 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)
 
             finally:
                 self._umount_all(target)
@@ -324,30 +429,49 @@ class BundleVolume():
                 self._unmap_partition(dev)
             losetup('-d', loop)
 
-    def create_image(self):
-
-        image = '/mnt/%s.diskdump' % uuid.uuid4().hex
+    def create_image(self, image):
+        """Given an image filename, this method will create an image out of the
+        running system.
+        """
 
-        disk_size = self.disk.device.getLength() * self.disk.device.sectorSize
+        size = self.disk.device.length * self.disk.device.sectorSize
 
         # Create sparse file to host the image
-        truncate("-s", "%d" % disk_size, image)
+        fd = os.open(image, os.O_WRONLY | os.O_CREAT)
+        try:
+            os.ftruncate(fd, size)
+        finally:
+            os.close(fd)
 
         self._create_partition_table(image)
-        end_sector = self._shrink_partitions(image)
+        end_sector, partitions = self._shrink_partitions(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
+
+        # Truncate image to the new size.
+        fd = os.open(image, os.O_RDWR)
+        try:
+            os.ftruncate(fd, size)
+        finally:
+            os.close(fd)
 
         # Check if the available space is enough to host the image
         dirname = os.path.dirname(image)
-        size = (end_sector + 1) * self.disk.device.sectorSize
-        self.out.output("Examining available space in %s ..." % dirname, False)
-        stat = os.statvfs(dirname)
-        available = stat.f_bavail * stat.f_frsize
-        if available <= size:
-            raise FatalError('Not enough space in %s to host the 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")
 
-        self._create_filesystems(image)
+        self._create_filesystems(image, partitions)
 
         return image