Files
rsync/support/idmap
2022-11-16 00:10:09 -08:00

46 lines
1.8 KiB
Python
Executable File

#!/usr/bin/env python3
# This helper script makes it easy to use a passwd or group file to map values
# in a LOCAL transfer. For instance, if you mount a backup that does not have
# the same passwd setup as the local machine, you can do a copy to/from the
# backup area as follows and get the differing ID values mapped just like a
# remote transfer to/from the backed-up machine would do:
#
# rsync -av --usermap=`idmap --to /mnt/backup/etc/passwd` \
# --groupmap=`idmap --to /mnt/backup/etc/group` \
# /some/src/ /mnt/backup/some/dest/
#
# rsync -av --usermap=`idmap --from /mnt/backup/etc/passwd` \
# --groupmap=`idmap --from /mnt/backup/etc/group` \
# /mnt/backup/some/src/ /some/dest/
import re, fileinput, argparse
NAME_ID_RE = re.compile(r'^(\w+):[^:]+:(\d+)')
def main():
maps = [ ]
for line in fileinput.input(args.files):
m = NAME_ID_RE.match(line)
if not m:
continue
if args.to:
pair = (m[1], m[2])
else:
pair = (m[2], m[1])
maps.append(':'.join(pair))
print(','.join(maps))
if __name__ == '__main__':
parser = argparse.ArgumentParser(description="Output usermap or groupmap args for rsync.", add_help=False)
action = parser.add_argument_group()
action = parser.add_mutually_exclusive_group(required=True)
action.add_argument("--from", action="store_true", help="Output the map for use on the sending side.")
action.add_argument("--to", action="store_true", help="Output the map for use on the receiving side.")
parser.add_argument("--help", "-h", action="help", help="Output this help message and exit.")
parser.add_argument("files", metavar="FILE", default='-', nargs='*', help="The file(s) that hold the name & id pairs. Defaults to stdin.")
args = parser.parse_args()
main()
# vim: sw=4 et