Added Maybe POSIXTime to SafeDropProof, which gets set when the proof is
based on a LockedCopy. If there are several LockedCopies, it uses the
closest expiry time. That is not optimal, it may be that the proof
expires based on one LockedCopy but another one has not expired. But
that seems unlikely to really happen, and anyway the user can just
re-run a drop if it fails due to expiry.
Pass the SafeDropProof to removeKey, which is responsible for checking
it for expiry in situations where that could be a problem. Which really
only means in Remote.Git.
Made Remote.Git check expiry when dropping from a local remote.
Checking expiry when dropping from a P2P remote is not yet implemented.
P2P.Protocol.remove has SafeDropProof plumbed through to it for that
purpose.
Fixing the remaining 2 build warnings should complete this work.
Note that the use of a POSIXTime here means that if the clock gets set
forward while git-annex is in the middle of a drop, it may say that
dropping took too long. That seems ok. Less ok is that if the clock gets
turned back a sufficient amount (eg 5 minutes), proof expiry won't be
noticed. It might be better to use the Monotonic clock, but that doesn't
advance when a laptop is suspended, and while there is the linux
Boottime clock, that is not available on other systems. Perhaps a
combination of POSIXTime and the Monotonic clock could detect laptop
suspension and also detect clock being turned back?
There is a potential future flag day where
p2pDefaultLockContentRetentionDuration is not assumed, but is probed
using the P2P protocol, and peers that don't support it can no longer
produce a LockedCopy. Until that happens, when git-annex is
communicating with older peers there is a risk of data loss when
a ssh connection closes during LOCKCONTENT.
This allows lockContentShared to lock content for eg, 10 minutes and
if the process then gets terminated before it can unlock, the content
will remain locked for that amount of time.
The Windows implementation is not yet tested.
In P2P.Annex, a duration of 10 minutes is used. This way, when p2pstdio
or remotedaemon is serving the P2P protocol, and is asked to
LOCKCONTENT, and that process gets killed, the content will not be
subject to deletion. This is not a perfect solution to
doc/todo/P2P_locking_connection_drop_safety.mdwn yet, but it gets most
of the way there, without needing any P2P protocol changes.
This is only done in v10 and higher repositories (or on Windows). It
might be possible to backport it to v8 or earlier, but it would
complicate locking even further, and without a separate lock file, might
be hard. I think that by the time this fix reaches a given user, they
will probably have been running git-annex 10.x long enough that their v8
repositories will have upgraded to v10 after the 1 year wait. And it's
not as if git-annex hasn't already been subject to this problem (though
I have not heard of any data loss caused by it) for 6 years already, so
waiting another fraction of a year on top of however long it takes this
fix to reach users is unlikely to be a problem.
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
This is groundwork for using watchFileSize for downloads from external
special remotes.
In Annex.Content.downloadUrl, this potentially avoids jitter in the
progress meter. When downloading with conduit, the meter gets updated based
on both the size of the file, and on the data flowing through conduit.
If that has not yet been flushed to the file, it seems possible for the
meter to run backwards when meter is updated with the file size.
It's probably only a few kb of jitter, so may not be visible.
Sponsored-by: Dartmouth College's DANDI project
Improve disk free space checking when transferring unsized keys to
local git remotes. Since the size of the object file is known, can
check that instead.
Getting unsized keys from local git remotes does not check the actual
object size. It would be harder to handle that direction because the size
check is run locally, before anything involving the remote is done. So it
doesn't know the size of the file on the remote.
Also, transferring unsized keys to other remotes, including ssh remotes and
p2p remotes don't do disk size checking for unsized keys. This would need a
change in protocol.
(It does seem like it would be possible to implement the same thing for
directory special remotes though.)
In some sense, it might be better to not ever do disk free checking for
unsized keys, than to do it only sometimes. A user might notice this
direction working and consider it a bug that the other direction does not.
On the other hand, disk reserve checking is not implemented for most
special remotes at all, and yet it is implemented for a few, which is also
inconsistent, but best effort. And so doing this best effort seems to make
some sense. Fundamentally, if the user wants the size to always be checked,
they should not use unsized keys.
Sponsored-by: Brock Spratlen on Patreon
migrate: Support adding size to URL keys that were added with --relaxed, by
running eg: git-annex migrate --backend=URL foo
Since url keys cannot be generated, that used to fail. Make it notice that
the backend is not changed, and just get the size of the content.
Sponsored-by: Brock Spratlen on Patreon
Minor optimisation, but a win in every case, except for a couple where
it's a wash.
Note that replaceFile still takes a FilePath, because it needs to
operate on Chars to truncate unicode filenames properly.
This makes annexFileMode be just an application of setAnnexPerm',
which avoids having 2 functions that do different versions of the same
thing.
Fixes some buggy behavior for some combinations of core.sharedRepository
and umask.
Sponsored-by: Jack Hill on Patreon
Converted warning and similar to use StringContainingQuotedPath. Most
warnings are static strings, some do refer to filepaths that need to be
quoted, and others don't need quoting.
Note that, since quote filters out control characters of even
UnquotedString, this makes all warnings safe, even when an attacker
sneaks in a control character in some other way.
When json is being output, no quoting is done, since json gets its own
quoting.
This does, as a side effect, make warning messages in json output not
be indented. The indentation is only needed to offset warning messages
underneath the display of the file they apply to, so that's ok.
Sponsored-by: Brett Eisenberg 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
Lock the local content for drop after getting it from src, to prevent another
process from using the local content as a copy and dropping it from src,
which would prevent dropping the local content after sending it to dest.
Support resuming an interrupted move that downloaded the content from
src, leaving the local content populated. In this case, the location log
has not been updated to say the content is present locally, so we can
assume that it's resuming and go ahead and drop the local content after
sending it to dest.
Note that if a `git-annex get` is being ran at the same time as a
`git-annex move --from --to`, it may get a file just before the move
processes it. So the location log has not been updated yet, and the move
thinks it's resuming. Resulting in local copy being dropped after it's
sent to the dest. This race is something we'll just have to live with,
it seems.
I also gave up on the idea of checking if the location log had been updated
by a `git-annex get` that is ran at the same time. That wouldn't work, because
the location log is precached in the seek stage, so reading it again after
sending the content to dest would not notice changes made to it, unless the cache
were invalidated, which would slow it down a lot. That idea anyway was subject
to races where it would not detect the concurrent `git-annex get`.
So concurrent `git-annex get` will have results that may be surprising.
To make that less surprising, updated the documentation of this feature to
be explicit that it downloads content to the local repository
temporarily.
Sponsored-by: Dartmouth College's DANDI project
The flush was only done Annex.run' to make sure that the queue was flushed
before git-annex exits. But, doing it there means that as soon as one
change gets queued, it gets flushed soon after, which contributes to
excessive writes to the database, slowing git-annex down.
(This does not yet speed git-annex up, but it is a stepping stone to
doing so.)
Database queues do not autoflush when garbage collected, so have to
be flushed explicitly. I don't think it's possible to make them
autoflush (except perhaps if git-annex sqitched to using ResourceT..).
The comment in Database.Keys.closeDb used to be accurate, since the
automatic flushing did mean that all writes reached the database even
when closeDb was not called. But now, closeDb or flushDb needs to be
called before stopping using an Annex state. So, removed that comment.
In Remote.Git, change to using quiesce everywhere that it used to use
stopCoProcesses. This means that uses on onLocal in there are just as
slow as before. I considered only calling closeDb on the local git remotes
when git-annex exits. But, the reason that Remote.Git calls stopCoProcesses
in each onLocal is so as not to leave git processes running that have files
open on the remote repo, when it's on removable media. So, it seemed to make
sense to also closeDb after each one, since sqlite may also keep files
open. Although that has not seemed to cause problems with removable
media so far. It was also just easier to quiesce in each onLocal than
once at the end. This does likely leave performance on the floor, so
could be revisited.
In Annex.Content.saveState, there was no reason to close the db,
flushing it is enough.
The rest of the changes are from auditing for Annex.new, and making
sure that quiesce is called, after any action that might possibly need
it.
After that audit, I'm pretty sure that the change to Annex.run' is
safe. The only concern might be that this does let more changes get
queued for write to the db, and if git-annex is interrupted, those will be
lost. But interrupting git-annex can obviously already prevent it from
writing the most recent change to the db, so it must recover from such
lost data... right?
Sponsored-by: Dartmouth College's Datalad project
Some small wins, almost certianly swamped by the system calls, but still
worthwhile progress on the RawFilePath conversion.
Sponsored-by: Erik Bjäreholt on Patreon
This reverts windows-specific parts of 5a98f2d509
There were no code paths in common between windows and unix, so this
will return Windows to the old behavior.
The problem that the commit talks about has to do with multiple different
locations where git-annex can store annex object files, but that is not
too relevant to Windows anyway, because on windows the filesystem is always
treated as criplled and/or symlinks are not supported, so it will only
use one object location. It would need to be using a repo populated
in another OS to have the other object location in use probably.
Then a drop and get could possibly lead to a dangling lock file.
And, I was not able to actually reproduce that situation happening
before making that commit, even when I forced a race. So making these
changes on windows was just begging trouble..
I suspect that the change that caused the reversion is in
Annex/Content/Presence.hs. It checks if the content file exists,
and then called modifyContentDirWhenExists, which seems like it would
not fail, but if something deleted the content file at that point,
that call would fail. Which would result in an exception being thrown,
which should not normally happen from a call to inAnnexSafe. That was a
windows-specific change; the unix side did not have an equivilant
change.
Sponsored-by: Dartmouth College's Datalad project
The purpose of this is to fix situations where the annex object file is
stored in a directory structure other than where annex symlinks point to.
But it will also move object files from the hashdirmixed back to
hashdirlower if the repo configuration makes that the normal location.
It would have been more work to avoid that than to let it do it.
Sponsored-by: Dartmouth College's Datalad project
It can be changed to 1 via a tuning, rather than the 2 this assumed. So
it would have tried to rmdir .git/annex/objects in that case, which
would not hurt anything, but is not what it is supposed to do.
Sponsored-by: Dartmouth College's Datalad project
If the content directory does not exist, then it does not make sense to
lock the content file, as it also does not exist, and so it's ok for the
lock operation to fail.
This avoids potential races where the content file exists but is then
deleted/renamed, while another process sees that it exists and goes to
lock it, resulting in a dangling lock file in an otherwise empty object
directory.
Also renamed modifyContent to modifyContentDir since it is not only
necessarily used for modifying content files, but also other files in
the content directory.
Sponsored-by: Dartmouth College's Datalad project
It did nothing, since at this point the link is dangling. But when there
is a thaw hook, it would probably not be happy to be asked to run on a
symlink, or might do something unexpected.
Sponsored-by: Dartmouth College's Datalad project
File matching options like --include will be rejected in situations where
there is no filename to match against. (Or where there is a filename but
it's not relative to the cwd, or otherwise seemed too bothersome to match
against.)
The addition of listKeys' was necessary to avoid using more memory in the
common case of "git-annex info". Adding a filterM would have caused the
list to buffer in memory and not stream. This is an ugly hack, but listKeys
had previously run Annex operations inside unafeInterleaveIO (for direct
mode). And matching against a matcher should hopefully not change any Annex
state.
This does allow for eg `git-annex info somefile --include=*.ext`
although why someone would want to do that I don't really know. But it
seems to make sense to allow it.
But, consider: `git-annex info ./somefile --include=somefile`
This does not match, so will not display info about somefile.
If the user really wants to, they can `--include=./somefile`.
Using matching options like --copies or --in=remote seems likely to be
slower than git-annex find with those options, because unlike such
commands, info does not have optimised streaming through the matcher.
Note that `git-annex info remote` is not the same as
`git-annex info --in remote`. The former shows info about all files in
the remote. The latter shows local keys that are also in that remote.
The output should make that clear, but this still seems like a point
where users could get confused.
Sponsored-by: Jochen Bartl on Patreon
The v10 upgrade should almost be safe now. What remains to be done is
notice when the v10 upgrade has occurred, while holding the shared lock,
and switch to using v10 lock files.
Sponsored-by: Dartmouth College's Datalad project
Upgrade the shared lock to an exclusive lock, and then delete the
lock file. If there is another process still holding the shared lock,
the first process will fail taking the exclusive lock, and not delete
the lock file; then the other process will later delete it.
Note that, in the time period where the exclusive lock is held, other
attempts to lock the content in place would fail. This is unlikely to be
a problem since it's a short period.
Other attempts to lock the content for removal would also fail in that
time period, but that's no different than a removal failing because
content is locked to prevent removal.
Sponsored-by: Dartmouth College's Datalad project
When dropping content, this was already done after deleting the content
file, but the lock file prevents deleting the directories. So, try the
deletion again.
This does mean there's a small added overhead of a failed rmdir().
Sponsored-by: Dartmouth College's Datalad project
This seems to be the best that can be done to avoid forever accumulating
the new content lock files, while being fully safe.
This is fixing code paths that have lingered unused since direct mode!
And direct mode seems to have been buggy in this area, since the content
lock file was deleted on unlock. But with a shared lock, there could be
another process that also had the lock file locked, and deleting it
invalidates that lock.
So, the lock file cannot be deleted after a shared lock. At least, not
wihout taking an exclusive lock first.. which I have not pursued yet but may.
After an exclusive lock, the lock file can be deleted. But there is
still a potential race, where the exclusive lock is held, and another
process gets the file open, just as the exclusive lock is dropped and
the lock file is deleted. That other process would be left with a file
handle it can take a shared lock of, but with no effect since the file
is deleted. Annex.Transfer also deletes lock files, and deals with this
same problem by using checkSaneLock, which is how I've dealt with it
here.
Sponsored-by: Dartmouth College's Datalad project
Windows has always used a separate lock file, but on unix, the content
file itself was locked, and in v9 that changes to also use a separate
lock file.
This needs to be tested more. Eg, what happens after dropping a file;
does the the content lock file get deleted too, or linger around?
Sponsored-by: Dartmouth College's Datalad project
Recover from corrupted content being received from a git remote due eg to a
wire error, by deleting the temporary file when it fails to verify. This
prevents a retry from failing again.
Reversion introduced in version 8.20210903, when incremental verification
was added.
Only the git remote seems to be affected, although it is certianly
possible that other remotes could later have the same issue. This only
affects things passed to getViaTmp that return (False, UnVerified) due to
verification failing. As far as getViaTmp can tell, that could just as well
mean that the transfer failed in a way that would resume, so it cannot
delete the temp file itself. Remote.Git and P2P.Annex use getViaTmp internally,
while other remotes do not, which is why only it seems affected.
A better fix perhaps would be to improve the types of the callback
passed to getViaTmp, so that some other value could be used to indicate
the state where the transfer succeeded but verification failed.
Sponsored-by: Boyd Stephen Smith Jr.
This opens the potential for the object file to be in place but
git-annex is interrupted before it can freeze it. git-annex fsck already
fixes that situation, which can also occur when lockContentForRemoval
thaws content.
Also improve comment to not be Windows-specific.
This change better supports Windows ACL management using
annex.freezecontent-command and annex.thawcontent-command and matches
the behaviour of adding an unlocked file.
By calling freezeContent after the file has moved into the annex,
the file's delete permission can be denied. If the file's delete
permission is denied before moving into the annex, the file cannot
be moved or deleted. If the file's delete permission is not denied after
moving into the annex, it will likely inherit a grant for the delete
permission which allows it to be deleted irrespective of the permissions
of the parent directory.
* When downloading urls fail, explain which urls failed for which
reasons.
* web: Avoid displaying a warning when downloading one url failed
but another url later succeeded.
Some other uses of downloadUrl use urls that are effectively internal use,
and should not all be displayed to the user on failure. Eg, Remote.Git
tries different urls where content could be located depending on how the
remote repo is set up. Exposing those urls to the user would lead to wild
goose chases. So had to parameterize it to control whether it displays urls
or not.
A side effect of this change is that when there are some youtube urls
and some regular urls, it will try regular urls first, even if the
youtube urls are listed first. This seems like an improvement if
anything, but in any case there's no defined order of urls that it's
supposed to use.
Sponsored-by: Dartmouth College's Datalad project
Except when configuration makes curl be used. It did not seem worth
trying to tail the file when curl is downloading.
But when an interrupted download is resumed, it does not read the whole
existing file to hash it. Same reason discussed in
commit 7eb3742e4b76d1d7a487c2c53bf25cda4ee5df43; that could take a long
time with no progress being displayed. And also there's an open http
request, which needs to be consumed; taking a long time to hash the file
might cause it to time out.
Also in passing implemented it for git and external special remotes when
downloading from the web. Several others like S3 are within striking
distance now as well.
Sponsored-by: Dartmouth College's DANDI project
This fixes the recent reversion that annex.verify is not honored,
because retrieveChunks was passed RemoteVerify baser, but baser
did not have export/import set up.
Sponsored-by: Dartmouth College's DANDI project
14683da9eb caused a test suite failure.
When the content of a key is not present, a LinkAnnexFailed is returned,
but replaceFile then tried to move the file into place, and since it was
not written, that crashed.
Sponsored-by: Boyd Stephen Smith Jr. on Patreon
This avoids it calling enteringStage VerifyStage when it's used in
places that only fall back to verification rarely, and which might be
called while in TransferStage and be going to perform a transfer after
the verification.
