revlog: move censor logic into main revlog class
Previously, the revlog class implemented dummy methods for
various censor-related functionality. Revision censoring was
(and will continue to be) only possible on filelog instances.
So filelog implemented these methods to perform something
reasonable.
A problem with implementing censoring on filelog is that
it assumes filelog is a revlog. Upcoming work to formalize
the filelog interface will make this not true.
Furthermore, the censoring logic is security-sensitive. I
think action-at-a-distance with custom implementation of core
revlog APIs in derived classes is a bit dangerous. I think at
a minimum the censor logic should live in revlog.py.
I was tempted to created a "censored revlog" class that
basically pulled these methods out of filelog. But, I wasn't
a huge fan of overriding core methods in child classes. A
reason to do that would be performance. However, the censoring
code only comes into play when:
* hash verification fails
* delta generation
* applying deltas from changegroups
The new code is conditional on an instance attribute. So the
overhead for running the censored code when the revlog isn't
censorable is an attribute lookup. All of these operations are
at least a magnitude slower than a Python attribute lookup. So
there shouldn't be a performance concern.
Differential Revision: https://phab.mercurial-scm.org/D3151
# blackbox.py - log repository events to a file for post-mortem debugging
#
# Copyright 2010 Nicolas Dumazet
# Copyright 2013 Facebook, Inc.
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
"""log repository events to a blackbox for debugging
Logs event information to .hg/blackbox.log to help debug and diagnose problems.
The events that get logged can be configured via the blackbox.track config key.
Examples::
[blackbox]
track = *
# dirty is *EXPENSIVE* (slow);
# each log entry indicates `+` if the repository is dirty, like :hg:`id`.
dirty = True
# record the source of log messages
logsource = True
[blackbox]
track = command, commandfinish, commandexception, exthook, pythonhook
[blackbox]
track = incoming
[blackbox]
# limit the size of a log file
maxsize = 1.5 MB
# rotate up to N log files when the current one gets too big
maxfiles = 3
"""
from __future__ import absolute_import
import errno
import re
from mercurial.i18n import _
from mercurial.node import hex
from mercurial import (
encoding,
registrar,
ui as uimod,
util,
)
from mercurial.utils import (
dateutil,
procutil,
)
# Note for extension authors: ONLY specify testedwith = 'ships-with-hg-core' for
# extensions which SHIP WITH MERCURIAL. Non-mainline extensions should
# be specifying the version(s) of Mercurial they are tested with, or
# leave the attribute unspecified.
testedwith = 'ships-with-hg-core'
cmdtable = {}
command = registrar.command(cmdtable)
configtable = {}
configitem = registrar.configitem(configtable)
configitem('blackbox', 'dirty',
default=False,
)
configitem('blackbox', 'maxsize',
default='1 MB',
)
configitem('blackbox', 'logsource',
default=False,
)
configitem('blackbox', 'maxfiles',
default=7,
)
configitem('blackbox', 'track',
default=lambda: ['*'],
)
lastui = None
def _openlogfile(ui, vfs):
def rotate(oldpath, newpath):
try:
vfs.unlink(newpath)
except OSError as err:
if err.errno != errno.ENOENT:
ui.debug("warning: cannot remove '%s': %s\n" %
(newpath, err.strerror))
try:
if newpath:
vfs.rename(oldpath, newpath)
except OSError as err:
if err.errno != errno.ENOENT:
ui.debug("warning: cannot rename '%s' to '%s': %s\n" %
(newpath, oldpath, err.strerror))
maxsize = ui.configbytes('blackbox', 'maxsize')
name = 'blackbox.log'
if maxsize > 0:
try:
st = vfs.stat(name)
except OSError:
pass
else:
if st.st_size >= maxsize:
path = vfs.join(name)
maxfiles = ui.configint('blackbox', 'maxfiles')
for i in xrange(maxfiles - 1, 1, -1):
rotate(oldpath='%s.%d' % (path, i - 1),
newpath='%s.%d' % (path, i))
rotate(oldpath=path,
newpath=maxfiles > 0 and path + '.1')
return vfs(name, 'a')
def wrapui(ui):
class blackboxui(ui.__class__):
@property
def _bbvfs(self):
vfs = None
repo = getattr(self, '_bbrepo', None)
if repo:
vfs = repo.vfs
if not vfs.isdir('.'):
vfs = None
return vfs
@util.propertycache
def track(self):
return self.configlist('blackbox', 'track')
def debug(self, *msg, **opts):
super(blackboxui, self).debug(*msg, **opts)
if self.debugflag:
self.log('debug', '%s', ''.join(msg))
def log(self, event, *msg, **opts):
global lastui
super(blackboxui, self).log(event, *msg, **opts)
if not '*' in self.track and not event in self.track:
return
if self._bbvfs:
ui = self
else:
# certain ui instances exist outside the context of
# a repo, so just default to the last blackbox that
# was seen.
ui = lastui
if not ui:
return
vfs = ui._bbvfs
if not vfs:
return
repo = getattr(ui, '_bbrepo', None)
if not lastui or repo:
lastui = ui
if getattr(ui, '_bbinlog', False):
# recursion and failure guard
return
ui._bbinlog = True
default = self.configdate('devel', 'default-date')
date = dateutil.datestr(default, '%Y/%m/%d %H:%M:%S')
user = procutil.getuser()
pid = '%d' % procutil.getpid()
formattedmsg = msg[0] % msg[1:]
rev = '(unknown)'
changed = ''
if repo:
ctx = repo[None]
parents = ctx.parents()
rev = ('+'.join([hex(p.node()) for p in parents]))
if (ui.configbool('blackbox', 'dirty') and
ctx.dirty(missing=True, merge=False, branch=False)):
changed = '+'
if ui.configbool('blackbox', 'logsource'):
src = ' [%s]' % event
else:
src = ''
try:
fmt = '%s %s @%s%s (%s)%s> %s'
args = (date, user, rev, changed, pid, src, formattedmsg)
with _openlogfile(ui, vfs) as fp:
fp.write(fmt % args)
except (IOError, OSError) as err:
self.debug('warning: cannot write to blackbox.log: %s\n' %
encoding.strtolocal(err.strerror))
# do not restore _bbinlog intentionally to avoid failed
# logging again
else:
ui._bbinlog = False
def setrepo(self, repo):
self._bbrepo = repo
ui.__class__ = blackboxui
uimod.ui = blackboxui
def uisetup(ui):
wrapui(ui)
def reposetup(ui, repo):
# During 'hg pull' a httppeer repo is created to represent the remote repo.
# It doesn't have a .hg directory to put a blackbox in, so we don't do
# the blackbox setup for it.
if not repo.local():
return
if util.safehasattr(ui, 'setrepo'):
ui.setrepo(repo)
# Set lastui even if ui.log is not called. This gives blackbox a
# fallback place to log.
global lastui
if lastui is None:
lastui = ui
repo._wlockfreeprefix.add('blackbox.log')
@command('^blackbox',
[('l', 'limit', 10, _('the number of events to show')),
],
_('hg blackbox [OPTION]...'))
def blackbox(ui, repo, *revs, **opts):
'''view the recent repository events
'''
if not repo.vfs.exists('blackbox.log'):
return
limit = opts.get(r'limit')
fp = repo.vfs('blackbox.log', 'r')
lines = fp.read().split('\n')
count = 0
output = []
for line in reversed(lines):
if count >= limit:
break
# count the commands by matching lines like: 2013/01/23 19:13:36 root>
if re.match('^\d{4}/\d{2}/\d{2} \d{2}:\d{2}:\d{2} .*> .*', line):
count += 1
output.append(line)
ui.status('\n'.join(reversed(output)))