contrib/hg-ssh

revset: predicate to avoid lookup errors

A query like

head() and (descendants("bad") and not descendants("fix"))

(testing if repo heads are affected by a bug) will abort with a
RepoLookupError if either badrev or fixrev aren't found inside
the repository, which is not very informative.

The new predicate returns an empty set for lookup errors, so

head() and (descendants(present("bad")) and not descendants(present("fix")))

will behave as wanted even if those revisions are not found.

#!/usr/bin/env python
#
# Copyright 2005-2007 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 version 2 or any later version.

"""
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}"
"""

# enable importing on demand to reduce startup time
from mercurial import demandimport; demandimport.enable()

from mercurial import dispatch

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:
        dispatch.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)