Oh, git, you made this so hard. Not determining if a branch pointed to some
corrupt object, that was easy, but dealing with corrupt branches using git
plumbing is a PITA.
I have not actually tested with 1.8.5, which is not yet relesaed, but
git.git commit f7cd8c50b9ab83e084e8f52653ecc8d90665eef2 changes -z
to also apply to output, without regards to back-compat. (But with pretty
good reasons.)
New code should work with both versions, by fingerprinting for NULs and
newlines.
gcrypt needs to be able to fast-forward the master branch. If a git
repository is set up with git init --shared --bare, it gets that set, and
pushing to it will then fail, even when it's up-to-date.
I forgot I had <$$> hidden away in Utility.Applicative.
It allows doing the same kind of currying as does >=*>
and I found using it made the code more readable for me.
(*>=> was not used)
This pulls off quite a nice trick: When given a path on rsync.net, it
determines if it is an encrypted git repository that the user has
the key to decrypt, and merges with it. This is works even when
the local repository had no idea that the gcrypt remote exists!
(As previously done with local drives.)
This commit sponsored by Pedro Côrte-Real
This is a massive win on OSX, which doesn't have a sha256sum normally.
Only use external hash commands when the file is > 1 mb,
since cryptohash is quite close to them in speed.
SHA is still used to calculate HMACs. I don't quite understand
cryptohash's API for those.
Used the following benchmark to arrive at the 1 mb number.
1 mb file:
benchmarking sha256/internal
mean: 13.86696 ms, lb 13.83010 ms, ub 13.93453 ms, ci 0.950
std dev: 249.3235 us, lb 162.0448 us, ub 458.1744 us, ci 0.950
found 5 outliers among 100 samples (5.0%)
4 (4.0%) high mild
1 (1.0%) high severe
variance introduced by outliers: 10.415%
variance is moderately inflated by outliers
benchmarking sha256/external
mean: 14.20670 ms, lb 14.17237 ms, ub 14.27004 ms, ci 0.950
std dev: 230.5448 us, lb 150.7310 us, ub 427.6068 us, ci 0.950
found 3 outliers among 100 samples (3.0%)
2 (2.0%) high mild
1 (1.0%) high severe
2 mb file:
benchmarking sha256/internal
mean: 26.44270 ms, lb 26.23701 ms, ub 26.63414 ms, ci 0.950
std dev: 1.012303 ms, lb 925.8921 us, ub 1.122267 ms, ci 0.950
variance introduced by outliers: 35.540%
variance is moderately inflated by outliers
benchmarking sha256/external
mean: 26.84521 ms, lb 26.77644 ms, ub 26.91433 ms, ci 0.950
std dev: 347.7867 us, lb 210.6283 us, ub 571.3351 us, ci 0.950
found 6 outliers among 100 samples (6.0%)
import Crypto.Hash
import Data.ByteString.Lazy as L
import Criterion.Main
import Common
testfile :: FilePath
testfile = "/run/shm/data" -- on ram disk
main = defaultMain
[ bgroup "sha256"
[ bench "internal" $ whnfIO internal
, bench "external" $ whnfIO external
]
]
sha256 :: L.ByteString -> Digest SHA256
sha256 = hashlazy
internal :: IO String
internal = show . sha256 <$> L.readFile testfile
external :: IO String
external = do
s <- readProcess "sha256sum" [testfile]
return $ fst $ separate (== ' ') s
Done using a mode witness, which ensures it's fixed everywhere.
Fixing catFileKey was a bear, because git cat-file does not provide a
nice way to query for the mode of a file and there is no other efficient
way to do it. Oh, for libgit2..
Note that I am looking at tree objects from HEAD, rather than the index.
Because I cat-file cannot show a tree object for the index.
So this fix is technically incomplete. The only cases where it matters
are:
1. A new large file has been directly staged in git, but not committed.
2. A file that was committed to HEAD as a symlink has been staged
directly in the index.
This could be fixed a lot better using libgit2.
Now can tell if a repo uses gcrypt or not, and whether it's decryptable
with the current gpg keys.
This closes the hole that undecryptable gcrypt repos could have before been
combined into the repo in encrypted mode.
When adding a removable drive, it's now detected if the drive contains
a gcrypt special remote, and that's all handled nicely. This includes
fetching the git-annex branch from the gcrypt repo in order to find
out how to set up the special remote.
Note that gcrypt repos that are not git-annex special remotes are not
supported. It will attempt to detect such a gcrypt repo and refuse
to use it. (But this is hard to do any may fail; see
https://github.com/blake2-ppc/git-remote-gcrypt/issues/6)
The problem with supporting regular gcrypt repos is that we don't know
what the gcrypt.participants setting is intended to be for the repo.
So even if we can decrypt it, if we push changes to it they might not be
visible to other participants.
Anyway, encrypted sneakernet (or mailnet) is now fully possible with the
git-annex assistant! Assuming that the gpg key distribution is handled
somehow, which the assistant doesn't yet help with.
This commit was sponsored by Navishkar Rao.
This is a git-remote-gcrypt encrypted special remote. Only sending files
in to the remote works, and only for local repositories.
Most of the work so far has involved making initremote work. A particular
problem is that remote setup in this case needs to generate its own uuid,
derivied from the gcrypt-id. That required some larger changes in the code
to support.
For ssh remotes, this will probably just reuse Remote.Rsync's code, so
should be easy enough. And for downloading from a web remote, I will need
to factor out the part of Remote.Git that does that.
One particular thing that will need work is supporting hot-swapping a local
gcrypt remote. I think it needs to store the gcrypt-id in the git config of the
local remote, so that it can check it every time, and compare with the
cached annex-uuid for the remote. If there is a mismatch, it can change
both the cached annex-uuid and the gcrypt-id. That should work, and I laid
some groundwork for it by already reading the remote's config when it's
local. (Also needed for other reasons.)
This commit was sponsored by Daniel Callahan.
Instead of populating the second-level Bloom filter with every key
referenced in every Git reference, consider only those which differ
from what's referenced in the index.
Incidentaly, unlike with its old behavior, staged
modifications/deletion/... will now be detected by 'unused'.
Credits to joeyh for the algorithm. :-)
Requires git 1.8.4 or newer. When it's installed, a background
git check-ignore process is run, and used to efficiently check ignores
whenever a new file is added.
Thanks to Adam Spiers, for getting the necessary support into git for this.
A complication is what to do about files that are gitignored but have
been checked into git anyway. git commands assume the ignore has been
overridden in this case, and not need any more overriding to commit a
changed version.
However, for the assistant to do the same, it would have to run git ls-files
to check if the ignored file is in git. This is somewhat expensive. Or it
could use the running git-cat-file process to query the file that way,
but that requires transferring the whole file content over a pipe, so it
can be quite expensive too, for files that are not git-annex
symlinks.
Now imagine if the user knows that a file or directory tree will be getting
frequent changes, and doesn't want the assistant to sync it, so gitignores
it. The assistant could overload the system with repeated ls-files checks!
So, I've decided that the assistant will not automatically commit changes
to files that are gitignored. This is a tradeoff. Hopefully it won't be a
problem to adjust .gitignore settings to not ignore files you want the
assistant to autocommit, or to manually git annex add files that are listed
in .gitignore.
(This could be revisited if git-annex gets access to an interface to check
the content of the index w/o forking a git command. This could be libgit2,
or perhaps a separate git cat-file --batch-check process, so it wouldn't
need to ship over the whole file content.)
This commit was sponsored by Francois Marier. Thanks!
This runs git-cat-file in non-batch mode for all files with spaces.
If a directory tree has a lot of them, and is in direct mode, even "git
annex add" when there are few new files will need a *lot* of forks!
The only reason buffering the whole file content to get the sha is not a
memory leak is that git-annex only ever uses this on symlinks.
This needs to be reverted as soon as a fix is available in git!
A git pathspec is a filename, except when it starts with ':', it's taken
to refer to a branch, etc. Rather than special case ':', any filename
starting with anything unusual is prefixed with "./"
This could have been a real mess to deal with, but luckily SafeCommand
is already extensively used and so we know at the type level the difference
between parameters that are files, and parameters that are command options.
Testing did show that Git.Queue was not using SafeCommand on
filenames fed to xargs. (Filenames starting with '-' worked before only
because -- was used to separate filenames from options when calling eg git
add.)
The test suite now passes with filenames starting with ':'. However, I did
not keep that change to it, because such filenames are probably not legal
on windows, and I have enough ugly windows ifdefs in there as it is.
This commit was sponsored by Otavio Salvador. Thanks!
Fuzz tests have shown that git cat-file --batch sometimes stops running.
It's not yet known why (no error message; repo seems ok). But this is
something we can deal with in the CoProcess framework, since all 3 types of
long-running git processes should be restartable if they fail.
Note that, as implemented, only IO errors are caught. So an error thrown
by the reveiver, when it sees something that is not valid output from
git cat-file (etc) will not cause a restart. I don't want it to retry
if git commands change their output or are just outputting garbage.
This does mean that if the command did a partial output and crashed in the
middle, it would still not be restarted.
There is currently no guard against restarting a command repeatedly, if,
for example, it crashes repeatedly on startup.
That's needed in files used to build the configure program.
For the other files, I'm keeping my __WINDOWS__ define, as I find that much easier to type.
I may search and replace it to use the mingw32_HOST_OS thing later.
Pass subcommand as a regular param, which allows passing git parameters
like -c before it. This was already done in the pipeing set of functions,
but not the command running set.
Two fixes. First, and most importantly, relax the isLinkToAnnex check
to only look for /annex/objects/, not [^|/].git/annex/objects. If
GIT_DIR is used with a detached work tree, the git directory is
not necessarily named .git.
There are important caveats with doing that at all, since git-annex will
make symlinks that point at GIT_DIR, which means that the relative path
between GIT_DIR and GIT_WORK_TREE needs to remain stable across all clones
of the repository.
----
The other fix is just fixing crazy and wrong code that, when GIT_DIR is
set, expects to still find a git repository in the path below the work
tree, and uses some of its configuration, and some of GIT_DIR. What was I
thinking, and why can't I seem to get this code right?
Making the pre-commit hook look at git diff-index to find changed direct
mode files and update the mappings works pretty well.
One case where it does not work is when a file is git annex added, and then
git rmed, and then this is committed. That's a no-op commit, so the hook
probably doesn't even run, and it certianly never notices that the file
was deleted, so the mapping will still have the original filename in it.
For this and other reasons, it's important that the mappings still be
treated as possibly inconsistent.
Also, the assistant now allows the pre-commit hook to run when in direct
mode, so the mappings also get updated there.
New setting, can be used to disable autocommit of changed files by the
assistant, while it still does data syncing and other tasks.
Also wired into webapp UI
Union merges involving two or more repositories could sometimes result in
data from one repository getting lost. This could result in the location
log data becoming wrong, and fsck being needed to fix it.
NB: I audited for any other occurrences of this problem. There are other
places than union merge where multiple changes are fed into update-index
in a stream, but they all involve working copy files being staged, or their
deletion being staged, and in this case it's fine for the later changes
to override the earlier ones.
git add --update cannot be used, because it'll stage typechanged direct
mode files. Intead, use ls-files to find deleted files, and stage them
ourselves.
It seems that no commit was made before when the scan staged deleted files.
(Probably masked since if files were added, a commit happened then..)
Now that I'm doing the staging, I was also able to fix that bug.
Wrote a better git remote name sanitizer. Git blows up on lots of weird
stuff, especially if it starts the remote name, but I managed to get
some common punctuation working.
Monitors git-annex branch for changes, which are noticed by the Merger
thread whenever the branch ref is changed (either due to an incoming push,
or a local change), and refreshes cached config values for modified config
files.
Rate limited to run no more often than once per minute. This is important
because frequent git-annex branch changes happen when files are being
added, or transferred, etc.
A primary use case is that, when preferred content changes are made,
and get pushed to remotes, the remotes start honoring those settings.
Other use cases include propigating repository description and trust
changes to remotes, and learning when a remote has added a new special
remote, so the webapp can present the GUI to enable that special remote
locally.
Also added a uuid.log cache. All other config files already had caches.
The old code was just wrong in taking fromPath of GIT_DIR -- that made an
localUnknown location with the GIT_DIR in it, which only worked by
accident, and failed in submodules.
When rsyncProgress pipes rsync's stdout, this turns out to cause a ssh
process started by rsync to be left behind as a zombie. I don't know why,
but my recent zombie reaping cleanup was correct, it's just that this other
zombie, that's not directly started by git-annex, was no longer reaped
due to changes in the cleanup. Make rsyncProgress reap the zombie started
by rsync, as a workaround.
FWIW, the process tree looks like this. It seems like the rsync child
is for some reason starting but not waiting on this extra ssh process.
Ssh connection caching may be involved -- disabling it seemed to change
the shape of the tree, but did not eliminate the zombie.
9378 pts/14 S+ 0:00 | \_ rsync -p --progress --inplace -4 -e 'ssh' '-S' ...
9379 pts/14 S+ 0:00 | | \_ ssh ...
9380 pts/14 S+ 0:00 | | \_ rsync -p --progress --inplace -4 -e 'ssh' '-S' ...
9381 pts/14 Z+ 0:00 | \_ [ssh] <defunct>
calcGitLink turns out to need it to be absolute, and it normally is,
but not if it's read from a .git file in a submodule, or perhaps from
GIT_DIR.
I should look into dropping this invariant.
Now that this is handled correctly, git-annex can be used in git submodules.
Also, fixed infelicity where Git.CurrentRepo and Git.Config.updateLocation
were both dealing with core.worktree. Now updateLocation handles it for
Local as well as for LocalUnknown repos.
I'm down to 9 places in the code that can produce unwaited for zombies.
Most of these are pretty innocuous, at least for now, are only
used in short-running commands, or commands that run a set of
actions and explicitly reap zombies after each one.
The one from Annex.Branch.files could be trouble later,
since both Command.Fsck and Command.Unused can trigger it,
and the assistant will be doing those eventally. Ditto the one in
Git.LsTree.lsTree, which Command.Unused uses.
The only ones currently affecting the assistant though, are
in Git.LsFiles. Several threads use several of those.
(And yeah, using pipes or ResourceT would be a less ad-hoc approach,
but I don't really feel like ripping my entire code base apart right
now to change a foundation monad. Maybe one of these days..)
Nearly everything that's reading from git is operating on a small
amount of output and has been switched to use that. Only pipeNullSplit
stuff continues using the lazy version that yields zombies.
Don't expose these as branches in refs/heads/. Instead hide them away in
refs/synced/ where only show-ref will find them.
Make unused only look at branches and tags, not these other things,
so it won't care if some stale sync ref used to use a file.
This means they don't need to be deleted, which could have
led to an incoming sync being missed.
Make Utility.Process wrap the parts of System.Process that I use,
and add debug logging to them.
Also wrote some higher-level code that allows running an action
with handles to a processes stdin or stdout (or both), and checking
its exit status, all in a single function call.
As a bonus, the debug logging now indicates whether the process
is being run to read from it, feed it data, chat with it (writing and
reading), or just call it for its side effect.
Test suite now passes with -threaded!
I traced back all the hangs with -threaded to System.Cmd.Utils. It seems
it's just crappy/unsafe/outdated, and should not be used. System.Process
seems to be the cool new thing, so converted all the code to use it
instead.
In the process, --debug stopped printing commands it runs. I may try to
bring that back later.
Note that even SafeSystem was switched to use System.Process. Since that
was a modified version of code from System.Cmd.Utils, it needed to be
converted too. I also got rid of nearly all calls to forkProcess,
and all calls to executeFile, which I'm also doubtful about working
well with -threaded.
Accept arbitrarily encoded repository filepaths etc when reading git config
output. This fixes support for remotes with unusual characters in their
names.
For example, a remote with a url of /tmp/çüş was previously
skipped, because the filename wasn't encoded right so it didn't think it
was available. And when setting the annex-uuid of a remote named "çüş",
it used to add it under a mis-encoded form of the remote's name. Both these
cases now work ok in my testing.
