##// END OF EJS Templates
revlog: add a mechanism to verify expected file position before appending...
revlog: add a mechanism to verify expected file position before appending If someone uses `hg debuglocks`, or some non-hg process writes to the .hg directory without respecting the locks, or if the repo's on a networked filesystem, it's possible for the revlog code to write out corrupted data. The form of this corruption can vary depending on what data was written and how that happened. We are in the "networked filesystem" case (though I've had users also do this to themselves with the "`hg debuglocks`" scenario), and most often see this with the changelog. What ends up happening is we produce two items (let's call them rev1 and rev2) in the .i file that have the same linkrev, baserev, and offset into the .d file, while the data in the .d file is appended properly. rev2's compressed_size is accurate for rev2, but when we go to decompress the data in the .d file, we use the offset that's recorded in the index file, which is the same as rev1, and attempt to decompress rev2.compressed_size bytes of rev1's data. This usually does not succeed. :) When using inline data, this also fails, though I haven't investigated why too closely. This shows up as a "patch decode" error. I believe what's happening there is that we're basically ignoring the offset field, getting the data properly, but since baserev != rev, it thinks this is a delta based on rev (instead of a full text) and can't actually apply it as such. For now, I'm going to make this an optional component and default it to entirely off. I may increase the default severity of this in the future, once I've enabled it for my users and we gain more experience with it. Luckily, most of my users have a versioned filesystem and can roll back to before the corruption has been written, it's just a hassle to do so and not everyone knows how (so it's a support burden). Users on other filesystems will not have that luxury, and this can cause them to have a corrupted repository that they are unlikely to know how to resolve, and they'll see this as a data-loss event. Refusing to create the corruption is a much better user experience. This mechanism is not perfect. There may be false-negatives (racy writes that are not detected). There should not be any false-positives (non-racy writes that are detected as such). This is not a mechanism that makes putting a repo on a networked filesystem "safe" or "supported", just *less* likely to cause corruption. Differential Revision: https://phab.mercurial-scm.org/D9952

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pager.py
83 lines | 2.6 KiB | text/x-python | PythonLexer
David Soria Parra
Use the pager given by the environment to display long output...
r6323 # pager.py - display output using a pager
#
# Copyright 2008 David Soria Parra <dsp@php.net>
#
Martin Geisler
updated license to be explicit about GPL version 2
r8225 # This software may be used and distributed according to the terms of the
Matt Mackall
Update license to GPLv2+
r10263 # GNU General Public License version 2 or any later version.
David Soria Parra
Use the pager given by the environment to display long output...
r6323 #
Brodie Rao
help: refer to user configuration file more consistently...
r12083 # To load the extension, add it to your configuration file:
David Soria Parra
Use the pager given by the environment to display long output...
r6323 #
# [extension]
Martin Geisler
hgext: enable extensions without "hgext." prefix in help texts
r10112 # pager =
David Soria Parra
Use the pager given by the environment to display long output...
r6323 #
timeless
pager: use single quotes in use warning
r29967 # Run 'hg help pager' to get info on configuration.
Christian Ebert
pager: make config info accessible with "hg help pager"
r6462
Augie Fackler
pager: move most help to a new help topic and deprecate extension
r31061 '''browse command output with an external pager (DEPRECATED)
Christian Ebert
pager: make config info accessible with "hg help pager"
r6462
Augie Fackler
pager: move most help to a new help topic and deprecate extension
r31061 Forcibly enable paging for individual commands that don't typically
request pagination with the attend-<command> option. This setting
takes precedence over ignore options and defaults::
Matt Mackall
pager: add attend-<command> option...
r21281
[pager]
attend-cat = false
Christian Ebert
pager: make config info accessible with "hg help pager"
r6462 '''
Augie Fackler
pager: use absolute_import
r28320 from __future__ import absolute_import
David Soria Parra
Use the pager given by the environment to display long output...
r6323
Augie Fackler
pager: use absolute_import
r28320 from mercurial import (
cmdutil,
commands,
dispatch,
extensions,
Boris Feld
configitems: register the 'pager.attend' config
r34496 registrar,
Augie Fackler
formatting: blacken the codebase...
r43346 )
David Soria Parra
Use the pager given by the environment to display long output...
r6323
Augie Fackler
extensions: change magic "shipped with hg" string...
r29841 # Note for extension authors: ONLY specify testedwith = 'ships-with-hg-core' for
Augie Fackler
extensions: document that `testedwith = 'internal'` is special...
r25186 # 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.
Augie Fackler
formatting: byteify all mercurial/ and hgext/ string literals...
r43347 testedwith = b'ships-with-hg-core'
Augie Fackler
hgext: mark all first-party extensions as such
r16743
Boris Feld
configitems: register the 'pager.attend' config
r34496 configtable = {}
configitem = registrar.configitem(configtable)
Augie Fackler
formatting: blacken the codebase...
r43346 configitem(
Augie Fackler
formating: upgrade to black 20.8b1...
r46554 b'pager',
b'attend',
default=lambda: attended,
Boris Feld
configitems: register the 'pager.attend' config
r34496 )
Augie Fackler
formatting: blacken the codebase...
r43346
David Soria Parra
Use the pager given by the environment to display long output...
r6323 def uisetup(ui):
Matt Mackall
extensions: use new wrapper functions
r7216 def pagecmd(orig, ui, options, cmd, cmdfunc):
Augie Fackler
formatting: byteify all mercurial/ and hgext/ string literals...
r43347 auto = options[b'pager'] == b'auto'
Augie Fackler
pager: move more behavior into core...
r30993 if auto and not ui.pageractive:
Matt Mackall
pager: break auto out of command check loop
r21279 usepager = False
Augie Fackler
formatting: byteify all mercurial/ and hgext/ string literals...
r43347 attend = ui.configlist(b'pager', b'attend')
ignore = ui.configlist(b'pager', b'ignore')
David Soria Parra
pager: honour internal aliases...
r19940 cmds, _ = cmdutil.findcmd(cmd, commands.table)
for cmd in cmds:
Augie Fackler
formatting: byteify all mercurial/ and hgext/ string literals...
r43347 var = b'attend-%s' % cmd
if ui.config(b'pager', var, None):
usepager = ui.configbool(b'pager', var, True)
Matt Mackall
pager: add attend-<command> option...
r21281 break
Augie Fackler
formatting: blacken the codebase...
r43346 if cmd in attend or (cmd not in ignore and not attend):
Matt Mackall
pager: break pager invocation out of command check loop
r21277 usepager = True
David Soria Parra
pager: honour internal aliases...
r19940 break
Matt Mackall
pager: break pager invocation out of command check loop
r21277
Augie Fackler
pager: move more behavior into core...
r30993 if usepager:
Augie Fackler
ui: add ignore-single-command functionality...
r30995 # Slight hack: the attend list is supposed to override
# the ignore list for the pager extension, but the
# core code doesn't know about attend, so we have to
# lobotomize the ignore list so that the extension's
# behavior is preserved.
Augie Fackler
formatting: byteify all mercurial/ and hgext/ string literals...
r43347 ui.setconfig(b'pager', b'ignore', b'', b'pager')
ui.pager(b'extension-via-attend-' + cmd)
Martin von Zweigbergk
pager: if old pager extensions is enabled, respect pager.attend...
r31406 else:
ui.disablepager()
Matt Mackall
extensions: use new wrapper functions
r7216 return orig(ui, options, cmd, cmdfunc)
David Soria Parra <dsp <at> php.net>
pager: Add a configuration to enable/disable the pager for certain commands...
r6417
Augie Fackler
formatting: byteify all mercurial/ and hgext/ string literals...
r43347 extensions.wrapfunction(dispatch, b'_runcommand', pagecmd)
Brodie Rao
pager: provide a default attend list...
r9841
Augie Fackler
formatting: blacken the codebase...
r43346
Augie Fackler
formatting: byteify all mercurial/ and hgext/ string literals...
r43347 attended = [b'annotate', b'cat', b'diff', b'export', b'glog', b'log', b'qdiff']