changegroup: capture revision delta in a data structure
The current changegroup generation code is tightly coupled to
the revlog API. This tight coupling makes it difficult to implement
alternate storage backends without requiring a large surface area
of the revlog API to be exposed. This is not desirable.
In order to support changegroup generation with non-revlog storage,
we'll need to abstract the concept of delta generation.
This commit is the first step down that road. We introduce a
data structure for representing a delta in a changegroup.
The API still leaves a lot to be desired. But at least we now
have separation between data and actions performed on it.
As part of this, we tweak behavior slightly: we no longer
concatenate the delta prefix with the metadata header. Instead,
we track and emit the prefix as a separate chunk. This shouldn't
have any meaningful impact since all the chunks just get sent to
the wire, the compressor, etc.
Because we're introducing a new object, this does add some
overhead to changegroup execution. `hg perfchangegroupchangelog`
on my clone of the Mercurial repo (~40,000 visible revisions in
the changelog) slows down a bit:
! wall 1.268600 comb 1.270000 user 1.270000 sys 0.000000 (best of 8)
! wall 1.419479 comb 1.410000 user 1.410000 sys 0.000000 (best of 8)
With for `hg bundle -t none-v2 -a /dev/null`:
before: real 6.610 secs (user 6.460+0.000 sys 0.140+0.000)
after: real 7.210 secs (user 7.060+0.000 sys 0.140+0.000)
I plan to claw back this regression in future commits. And I may
even do away with this data structure once the refactor is complete.
For now, it makes things easier to comprehend.
Differential Revision: https://phab.mercurial-scm.org/D4075
# factotum.py - Plan 9 factotum integration for Mercurial
#
# Copyright (C) 2012 Steven Stallion <sstallion@gmail.com>
#
# This program is free software; you can redistribute it and/or modify it
# under the terms of the GNU General Public License as published by the
# Free Software Foundation; either version 2 of the License, or (at your
# option) any later version.
#
# This program is distributed in the hope that it will be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
# Public License for more details.
#
# You should have received a copy of the GNU General Public License along
# with this program; if not, write to the Free Software Foundation, Inc.,
# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
'''http authentication with factotum
This extension allows the factotum(4) facility on Plan 9 from Bell Labs
platforms to provide authentication information for HTTP access. Configuration
entries specified in the auth section as well as authentication information
provided in the repository URL are fully supported. If no prefix is specified,
a value of "*" will be assumed.
By default, keys are specified as::
proto=pass service=hg prefix=<prefix> user=<username> !password=<password>
If the factotum extension is unable to read the required key, one will be
requested interactively.
A configuration section is available to customize runtime behavior. By
default, these entries are::
[factotum]
executable = /bin/auth/factotum
mountpoint = /mnt/factotum
service = hg
The executable entry defines the full path to the factotum binary. The
mountpoint entry defines the path to the factotum file service. Lastly, the
service entry controls the service name used when reading keys.
'''
from __future__ import absolute_import
import os
from mercurial.i18n import _
from mercurial import (
error,
httpconnection,
registrar,
url,
util,
)
urlreq = util.urlreq
passwordmgr = url.passwordmgr
ERRMAX = 128
_executable = _mountpoint = _service = None
configtable = {}
configitem = registrar.configitem(configtable)
configitem('factotum', 'executable',
default='/bin/auth/factotum',
)
configitem('factotum', 'mountpoint',
default='/mnt/factotum',
)
configitem('factotum', 'service',
default='hg',
)
def auth_getkey(self, params):
if not self.ui.interactive():
raise error.Abort(_('factotum not interactive'))
if 'user=' not in params:
params = '%s user?' % params
params = '%s !password?' % params
os.system("%s -g '%s'" % (_executable, params))
def auth_getuserpasswd(self, getkey, params):
params = 'proto=pass %s' % params
while True:
fd = os.open('%s/rpc' % _mountpoint, os.O_RDWR)
try:
os.write(fd, 'start %s' % params)
l = os.read(fd, ERRMAX).split()
if l[0] == 'ok':
os.write(fd, 'read')
status, user, passwd = os.read(fd, ERRMAX).split(None, 2)
if status == 'ok':
if passwd.startswith("'"):
if passwd.endswith("'"):
passwd = passwd[1:-1].replace("''", "'")
else:
raise error.Abort(_('malformed password string'))
return (user, passwd)
except (OSError, IOError):
raise error.Abort(_('factotum not responding'))
finally:
os.close(fd)
getkey(self, params)
def monkeypatch_method(cls):
def decorator(func):
setattr(cls, func.__name__, func)
return func
return decorator
@monkeypatch_method(passwordmgr)
def find_user_password(self, realm, authuri):
user, passwd = self.passwddb.find_user_password(realm, authuri)
if user and passwd:
self._writedebug(user, passwd)
return (user, passwd)
prefix = ''
res = httpconnection.readauthforuri(self.ui, authuri, user)
if res:
_, auth = res
prefix = auth.get('prefix')
user, passwd = auth.get('username'), auth.get('password')
if not user or not passwd:
if not prefix:
prefix = realm.split(' ')[0].lower()
params = 'service=%s prefix=%s' % (_service, prefix)
if user:
params = '%s user=%s' % (params, user)
user, passwd = auth_getuserpasswd(self, auth_getkey, params)
self.add_password(realm, authuri, user, passwd)
self._writedebug(user, passwd)
return (user, passwd)
def uisetup(ui):
global _executable
_executable = ui.config('factotum', 'executable')
global _mountpoint
_mountpoint = ui.config('factotum', 'mountpoint')
global _service
_service = ui.config('factotum', 'service')