+
+ # Verify that the list of segments included with the snapshot was
+ # actually accurate: covered all segments that were really read, and
+ # doesn't contain duplicates.
+ listed_segments = set(d['Segments'].split())
+ if lbs.accessed_segments - listed_segments:
+ print "Error: Some segments not listed in descriptor!"
+ print sorted(list(lbs.accessed_segments - listed_segments))
+ if listed_segments - lbs.accessed_segments :
+ print "Warning: Extra unused segments listed in descriptor!"
+ print sorted(list(listed_segments - lbs.accessed_segments))
+ store.cleanup()
+
+# Restore a snapshot, or some subset of files from it
+def cmd_restore_snapshot(args):
+ get_passphrase()
+ lowlevel = lbs.LowlevelDataStore(options.store)
+ store = lbs.ObjectStore(lowlevel)
+ snapshot = lbs.parse_full(store.load_snapshot(args[0]))
+ check_version(snapshot['Format'])
+ destdir = args[1]
+ paths = args[2:]
+
+ def matchpath(path):
+ "Return true if the specified path should be included in the restore."
+
+ # No specification of what to restore => restore everything
+ if len(paths) == 0: return True
+
+ for p in paths:
+ if path == p: return True
+ if path.startswith(p + "/"): return True
+ return False
+
+ def warn(m, msg):
+ print "Warning: %s: %s" % (m.items.name, msg)
+
+ # Phase 1: Read the complete metadata log and create directory structure.
+ metadata_items = []
+ metadata_paths = {}
+ metadata_segments = {}
+ for m in lbs.iterate_metadata(store, snapshot['Root']):
+ pathname = os.path.normpath(m.items.name)
+ while os.path.isabs(pathname):
+ pathname = pathname[1:]
+ if not matchpath(pathname): continue
+
+ destpath = os.path.join(destdir, pathname)
+ if m.items.type == 'd':
+ path = destpath
+ else:
+ (path, filename) = os.path.split(destpath)
+
+ metadata_items.append((pathname, m))
+ if m.items.type in ('-', 'f'):
+ metadata_paths[pathname] = m
+ for block in m.data():
+ (segment, object, checksum, slice) \
+ = lbs.ObjectStore.parse_ref(block)
+ if segment not in metadata_segments:
+ metadata_segments[segment] = set()
+ metadata_segments[segment].add(pathname)
+
+ try:
+ if not os.path.isdir(path):
+ print "mkdir:", path
+ os.makedirs(path)
+ except Exception, e:
+ warn(m, "Error creating directory structure: %s" % (e,))
+ continue
+
+ # Phase 2: Restore files, ordered by how data is stored in segments.
+ def restore_file(pathname, m):
+ assert m.items.type in ('-', 'f')
+ print "extract:", pathname
+ destpath = os.path.join(destdir, pathname)
+
+ file = open(destpath, 'wb')
+ verifier = lbs.ChecksumVerifier(m.items.checksum)
+ size = 0
+ for block in m.data():
+ data = store.get(block)
+ verifier.update(data)
+ size += len(data)
+ file.write(data)
+ file.close()
+ if int(m.fields['size']) != size:
+ raise ValueError("File size does not match!")
+ if not verifier.valid():
+ raise ValueError("Bad checksum found")
+
+ while metadata_segments:
+ (segment, items) = metadata_segments.popitem()
+ print "+ Segment", segment
+ for pathname in sorted(items):
+ if pathname in metadata_paths:
+ restore_file(pathname, metadata_paths[pathname])
+ del metadata_paths[pathname]
+
+ print "+ Remaining files"
+ while metadata_paths:
+ (pathname, m) = metadata_paths.popitem()
+ restore_file(pathname, m)
+
+ # Phase 3: Restore special files (symlinks, devices).
+ # Phase 4: Restore directory permissions and modification times.
+ for (pathname, m) in reversed(metadata_items):
+ print "permissions:", pathname
+ destpath = os.path.join(destdir, pathname)
+ (path, filename) = os.path.split(destpath)
+
+ # TODO: Check for ../../../paths that might attempt to write outside
+ # the destination directory. Maybe also check attempts to follow
+ # symlinks pointing outside?
+
+ try:
+ if m.items.type in ('-', 'f', 'd'):
+ pass
+ elif m.items.type == 'l':
+ try:
+ target = m.items.target
+ except:
+ # Old (v0.2 format) name for 'target'
+ target = m.items.contents
+ os.symlink(target, destpath)
+ elif m.items.type == 'p':
+ os.mkfifo(destpath)
+ elif m.items.type in ('c', 'b'):
+ if m.items.type == 'c':
+ mode = 0600 | stat.S_IFCHR
+ else:
+ mode = 0600 | stat.S_IFBLK
+ os.mknod(destpath, mode, os.makedev(*m.items.device))
+ elif m.items.type == 's':
+ pass # TODO: Implement
+ else:
+ warn(m, "Unknown type code: " + m.items.type)
+ continue
+
+ except Exception, e:
+ warn(m, "Error restoring: %s" % (e,))
+ continue
+
+ try:
+ uid = m.items.user[0]
+ gid = m.items.group[0]
+ os.lchown(destpath, uid, gid)
+ except Exception, e:
+ warn(m, "Error restoring file ownership: %s" % (e,))
+
+ if m.items.type == 'l':
+ continue
+
+ try:
+ os.chmod(destpath, m.items.mode)
+ except Exception, e:
+ warn(m, "Error restoring file permissions: %s" % (e,))
+
+ try:
+ os.utime(destpath, (time.time(), m.items.mtime))
+ except Exception, e:
+ warn(m, "Error restoring file timestamps: %s" % (e,))
+