Detect when a preferred content expression contains "not present", which
would lead to repeatedly getting and then dropping files, and make it never
match. This also applies to "not balanced" and "not sizebalanced".
--explain will tell the user when this happens
Note that getMatcher calls matchMrun' and does not check for unstable
negated limits. While there is no --present anyway, if there was,
it would not make sense for --not --present to complain about
instability and fail to match.
Only when the preferred content expression being matched uses balanced
preferred content is this overhead needed.
It might be possible to eliminate the locking entirely. Eg, check the
live changes before and after the action and re-run if they are not
stable. For now, this is good enough, it avoids existing preferred
content getting slow. If balanced preferred content turns out to be too
slow to check, that could be tried later.
I've tested the behavior of the thread that waits for the LiveUpdate to
be finished, and it does get signaled and exit cleanly when the
LiveUpdate is GCed instead.
Made finishedLiveUpdate wait for the thread to finish updating the
database.
There is a case where GC doesn't happen in time and the database is left
with a live update recorded in it. This should not be a problem as such
stale data can also happen when interrupted and will need to be detected
when loading the database.
Balanced preferred content expressions now call startLiveUpdate.
Each command that first checks preferred content (and/or required
content) and then does something that can change the sizes of
repositories needs to call prepareLiveUpdate, and plumb it through the
preferred content check and the location log update.
So far, only Command.Drop is done. Many other commands that don't need
to do this have been updated to keep working.
There may be some calls to NoLiveUpdate in places where that should be
done. All will need to be double checked.
Not currently in a compilable state.
When the specified number of copies is > 1, and some repositories are
too full, it can be better to move content from them to other less full
repositories, in order to make space for new content.
annex.fullybalancedthreshhold is documented, but not implemented yet
This is not tested very well yet, and is known to sometimes take several
runs to stabalize.
Might want to make --rebalance turn balanced=group:N where N > 1
to fullysizebalanced=group:N. Have not yet determined if that will
improve situations enough to be worth the extra work.
At this point the RepoSize database is getting populated, and it
all seems to be working correctly. Incremental updates still need to be
done to make it performant.
Plan is to run this when populating Annex.reposizes on demand.
So Annex.reposizes will be up-to-date with the journal, including
crucially journal entries for private repositories. But also
anything that has been written to the journal by another process,
especially if the process was ran with annex.alwayscommit=false.
From there, Annex.reposizes can be kept up to date with changes made
by the running process.
This will be used to prime the RepoSizes database, which will always
contain values that correpond to information in the git-annex branch, so
without anything from journal files.
Factored out overJournalFileContents which will later be used to
update Annex.reposizes to include information from journal files.
This will be partitcularly important to support private UUIDs which only
ever get to journal files and not to the branch.
This fully fixes --rebalance stability, and also deals with an issue
where a file is present in each balanced repository and it didn't want
to remove it from any.
git-annex info was displaying a message that didn't make sense in
context.
In calcRepoSizes, it seems better to return the information from the
git-annex branch, rather than giving up. Especially since balanced
preferred content uses it, and we can't just give up evaluating a
preferred content expression if git-annex is to be usable in such a
readonly repo.
Commit 6d7ecd9e5d nobly wanted git-annex
to behave the same with such unmerged branches as it does when it can
merge them. But for the purposes of preferred content, it seems to me
there's a sense that such an unmerged branch is the same as a remote we
have not pulled from. The balanced preferred content will either way
operate under outdated information, and so make not the best choices.
This is very innefficient, it will need to be optimised not to
calculate the sizes of repos every time.
Also, fixed a bug in balancedPicker that caused it to pick a too high
index when some repos were excluded due to being full.
This deals with the possible security problem that someone could make an
unusually low UUID and generate keys that are all constructed to hash to
a number that, mod the number of repositories in the group, == 0.
So balanced preferred content would always put those keys in the
repository with the low UUID as long as the group contains the
number of repositories that the attacker anticipated.
Presumably the attacker than holds the data for ransom? Dunno.
Anyway, the partial solution is to use HMAC (sha256) with all the UUIDs
combined together as the "secret", and the key as the "message". Now any
change in the set of UUIDs in a group will invalidate the attacker's
constructed keys from hashing to anything in particular.
Given that there are plenty of other things someone can do if they can
write to the repository -- including modifying preferred content so only
their repository wants files, and numcopies so other repositories drom
them -- this seems like safeguard enough.
Note that, in balancedPicker, combineduuids is memoized.
This all works fine. But it doesn't check repository sizes yet, and
without repository size checking, once a repository gets full, there
will be no other repository that will want its files.
Use of sha2 seems unncessary, probably alder2 or md5 or crc would have
been enough. Possibly just summing up the bytes of the key mod the number
of repositories would have sufficed. But sha2 is there, and probably
hardware accellerated. I doubt very much there is any security benefit
to using it though. If someone wants to construct a key that will be
balanced onto a given repository, sha2 is certianly not going to stop
them.
Handled limitCopies, as well as everything using fromNumCopies and
fromMinCopies.
This should be everything, probably.
Note that, git-annex info displays a count of repositories, which still
includes cluster. I think that's ok. It would be possible to filter out
clusters there, but to the user they're pretty much just another
repository. The numcopies displayed by eg `git-annex info .` does not
include clusters.
Considerable difficulty to work around an import cycle. Had to move the
list of backends (except for VURL) to Backend.Variety to VURL could use
it.
Sponsored-by: Kevin Mueller on Patreon
Using == and != proved too hard to read, so went with [TRUE] and [FALSE]
after the term. I would kind of liked to have used emojis for a green
check and red X, but probably that is too fancy to be a good idea.
Make --explain output be inside [ ] with whitespace around them, to
avoid it ending with eg "[FALSE]]" and to make it easier to visually
find the start of it.
Sponsored-by: Dartmouth College's DANDI project
And annex.largefiles and annex.addunlocked.
Also git-annex matchexpression --explain explains why its input
expression matches or fails to match.
When there is no limit, avoid explaining why the lack of limit
matches. This is also done when no preferred content expression is set,
although in a few cases it defaults to a non-empty matcher, which will
be explained.
Sponsored-by: Dartmouth College's DANDI project
Currently it only displays explanations of options like --in and --copies.
In the future, it should explain preferred content expression evaluation
and other decisions.
The explanations of a few things could be better. In particular,
"standard" will just appear as-is (or as "!standard" if it doesn't
match), rather than explaining why the standard preferred content expression
for the group matches or not.
Currently as implemented, it goes to stdout, and so commands like
git-annex find that have custom output will not display --explain
information. Perhaps that should change, dunno.
Sponsored-by: Dartmouth College's DANDI project
giveup changed to filter out control characters. (It is too low level to
make it use StringContainingQuotedPath.)
error still does not, but it should only be used for internal errors,
where the message is not attacker-controlled.
Changed a lot of existing error to giveup when it is not strictly an
internal error.
Of course, other exceptions can still be thrown, either by code in
git-annex, or a library, that include some attacker-controlled value.
This does not guard against those.
Sponsored-by: Noam Kremen on Patreon
Works around this bug in unix-compat:
https://github.com/jacobstanley/unix-compat/issues/56
getFileStatus and other FilePath using functions in unix-compat do not do
UNC conversion on Windows.
Made Utility.RawFilePath use convertToWindowsNativeNamespace to do the
necessary conversion on windows to support long filenames.
Audited all imports of System.PosixCompat.Files to make sure that no
functions that operate on FilePath were imported from it. Instead, use
the equvilants from Utility.RawFilePath. In particular the
re-export of that module in Common had to be removed, which led to lots
of other changes throughout the code.
The changes to Build.Configure, Build.DesktopFile, and Build.TestConfig
make Utility.Directory not be needed to build setup. And so let it use
Utility.RawFilePath, which depends on unix, which cannot be in
setup-depends.
Sponsored-by: Dartmouth College's Datalad project
Added --anything (and --nothing). Eg, git-annex find --anything will list
all annexed files whether or not the content is present. This is slightly
faster and clearer than --include=* or --exclude=*
While I can't imagine how --nothing will be used, preferred content
expressions already had anything and nothing, so might as well support both
as matching options as well.
Sponsored-by: Dartmouth College's Datalad project
Fix crash importing from a directory special remote that contains a broken
symlink.
The crash was in listImportableContentsM but some other places in
Remote.Directory also seemed like they could have the same problem.
Also audited for other places that have such a problem. Not all calls
to getFileStatus are bad, in some cases it's better to crash on something
unexpected. For example, `git-annex import path` when the path is a broken
symlink should crash, the same as when it does not exist. Many of the
getFileStatus calls are like that, particularly when they involve
.git/annex/objects which should never have a broken symlink in it.
Fixed a few other possible cases of the problem.
Sponsored-by: Lawrence Brogan on Patreon
Ignore annex.numcopies set to 0 in gitattributes or git config, or by
git-annex numcopies or by --numcopies, since that configuration would make
git-annex easily lose data. Same for mincopies.
This is a continuation of the work to make data only be able to be lost
when --force is used. It earlier led to the --trust option being disabled,
and similar reasoning applies here.
Most numcopies configs had docs that strongly discouraged setting it to 0
anyway. And I can't imagine a use case for setting to 0. Not that there
might not be one, but it's just so far from the intended use case of
git-annex, of managing and storing your data, that it does not seem like
it makes sense to cater to such a hypothetical use case, where any
git-annex drop can lose your data at any time.
Using a smart constructor makes sure every place avoids 0. Note that this
does mean that NumCopies is for the configured desired values, and not the
actual existing number of copies, which of course can be 0. The name
configuredNumCopies is used to make that clear.
Sponsored-by: Brock Spratlen on Patreon
The normalisation of filenames turns out to be the tricky part here,
because the associated files coming out of the keys db may look like
"./foo/bar" or "../bar". For the former to match a glob like "foo/*",
it needs to be normalised.
Note that, on windows, normalise "./foo/bar" = "foo\\bar"
which a glob like "foo/*" won't match. So the glob is matched a second
time, on the toInternalGitPath, so allowing the user to provide a glob
with the slashes in either direction. However, this still won't support
some wacky edge cases like the user providing a glob of "foo/bar\\*"
Sponsored-by: Dartmouth College's Datalad project
Added LinkType to ProvidedInfo, and unified MatchingKey with
ProvidedInfo. They're both used in the same way, so there was no real
reason to keep separate.
Note that addLocked and addUnlocked still set matchNeedsFileName,
because to handle MatchingFile, they do need it. However, they
don't use it when MatchingInfo is provided. This should be ok,
the --branch case will be able skip checking matchNeedsFileName,
since it will provide a filename in any case.
Previously such nonsensical combinations always treated the matching option
as if it didn't match.
For now, made find --branch refuse matching options that need a
filename, because one is not provided to them in a way they'll use.
There's an open bug report to support it, but making it error out is
better than the old behavior of not finding what it was asked to.
Also, made --mimetype combined with eg --all work, by looking at the
object file when operating on keys.
It got broken in several ways by the streaming seeking optimisations
around version 8.20201007.
Moved time limit checking out of the matcher, which was a hack in the
first place. So everywhere that uses Limit.getMatcher needs to check
time limit. Well, almost everywhere. Command.Info uses it, but it does
not make sense to time limit getting info. And Command.MultiCast uses it
just to build up a list of files that then get passed to a command, so
it would never have hit the timeout in a useful way.
This implementation is a little more expensive when at time limit than
necessary, since it continues seeking only to discard everything after the
time limit. I did try making it close the file handles to force a faster
shutdown, but that didn't work and hung. Could certianly be improved
somehow, but seeking is probably not the expensive bit when a time limit
is hit, so this seems acceptable for now.
And vice-versa, but it's better to use '/' for portability.
Notably, standardPreferredContent contains "archive/*" and that might not
match if the filename ends up coming in with the slashes the other way
around.
MatchingKey is not the thing to use when matching on actual worktreee
files.
Fix reversion in 8.20201116 that made include= and exclude= in
preferred/required content expressions match a path relative to the current
directory, rather than the path from the top of the repository.
Lots of nice wins from this in avoiding unncessary work, and I think
nothing got slower.
This commit was sponsored by Boyd Stephen Smith Jr. on Patreon.
Import small files into git, the same as is done when importing with content.
Which means, for small files, --no-content does download them.
If the largefiles expression needs the file content available
(due to mimetype or mimeencoding being used), the import will fail.
This commit was sponsored by Jake Vosloo on Patreon.
