contrib/hg-ssh

Avoid some false positives for addremove -s

The original code uses the similary score

  1 - len(diff(after, before)) / len(after)

The diff can at most be the size of the 'before' file, so any small
'before' file would be considered very similar. Removing an empty file
would cause all files added in the same revision to be considered
copies of the removed file.

This changes the metric to

  bytes_overlap(before, after) / len(before + after)

i.e. the actual percentage of bytes shared between the two files.

#!/usr/bin/env python
#
# Copyright 2005, 2006 by Intevation GmbH <[e-mail]>
# Author(s):
# Thomas Arendsen Hein <[e-mail]>
#
# This software may be used and distributed according to the terms
# of the GNU General Public License, incorporated herein by reference.

"""
hg-ssh - a wrapper for ssh access to a limited set of mercurial repos

To be used in ~/.ssh/authorized_keys with the "command" option, see sshd(8):
command="hg-ssh path/to/repo1 /path/to/repo2 ~/repo3 ~user/repo4" ssh-dss ...
(probably together with these other useful options:
 no-port-forwarding,no-X11-forwarding,no-agent-forwarding)

This allows pull/push over ssh to to the repositories given as arguments.

If all your repositories are subdirectories of a common directory, you can
allow shorter paths with:
command="cd path/to/my/repositories && hg-ssh repo1 subdir/repo2"

You can use pattern matching of your normal shell, e.g.:
command="cd repos && hg-ssh user/thomas/* projects/{mercurial,foo}"
"""

from mercurial import commands

import sys, os

cwd = os.getcwd()
allowed_paths = [os.path.normpath(os.path.join(cwd, os.path.expanduser(path)))
                 for path in sys.argv[1:]]
orig_cmd = os.getenv('SSH_ORIGINAL_COMMAND', '?')

if orig_cmd.startswith('hg -R ') and orig_cmd.endswith(' serve --stdio'):
    path = orig_cmd[6:-14]
    repo = os.path.normpath(os.path.join(cwd, os.path.expanduser(path)))
    if repo in allowed_paths:
        commands.dispatch(['-R', repo, 'serve', '--stdio'])
    else:
        sys.stderr.write("Illegal repository %r\n" % repo)
        sys.exit(-1)
else:
    sys.stderr.write("Illegal command %r\n" % orig_cmd)
    sys.exit(-1)