view mercurial/txnutil.py @ 34963:5e27afeddaee stable

subrepo: add config option to reject any subrepo operations (SEC)

This is an alternative workaround for the issue5730.

Perhaps this is the simplest way of disabling subrepo operations. It does
nothing clever, but just aborts if Mercurial starts accessing to a subrepo.

I think Greg's patch is more useful since it allows us to at least check
out the parent repository. However, that would be confusing if the default
is flipped to checkout=False and subrepos are silently ignored.

I don't like the config name 'allowed', but I couldn't get any better name.

# txnutil.py - transaction related utilities
#
#  Copyright FUJIWARA Katsunori <[e-mail]> and others
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

from __future__ import absolute_import

import errno

from . import (
    encoding,
)

def mayhavepending(root):
    '''return whether 'root' may have pending changes, which are
    visible to this process.
    '''
    return root == encoding.environ.get('HG_PENDING')

def trypending(root, vfs, filename, **kwargs):
    '''Open  file to be read according to HG_PENDING environment variable

    This opens '.pending' of specified 'filename' only when HG_PENDING
    is equal to 'root'.

    This returns '(fp, is_pending_opened)' tuple.
    '''
    if mayhavepending(root):
        try:
            return (vfs('%s.pending' % filename, **kwargs), True)
        except IOError as inst:
            if inst.errno != errno.ENOENT:
                raise
    return (vfs(filename, **kwargs), False)