Fix hang when dropping content needs to lock the content on a ssh remote,
which occurred when the remote has git-annex version 5.20151019 or newer.
Analysis: `race` runs 2 threads at once, and the hGetLine finishes first.
So, it tries to cancel the waitForProcess, but unfortunately that is making
a foreign call and so cannot be canceled. The remote git-annex-shell
is waiting for a line on stdin before it will exit. Deadlock.
This only occurred sometimes; I reproduced it going from darkstar to
elephant, but not from darkstar to darkstar. Not sure how that fits into
the above analysis -- perhaps a race condition is also involved?
Fixed by not using `race`; now the hGetLine will fail with an exception
if the remote git-annex-shell exits without any output.
In copyFromRemote, it used to check isDirect, but that was not needed;
the remote is sending the file, so it doesn't matter if the local,
receiving repository is in direct mode or not. And, since the content is not
present, yet, it's certianly not unlocked. Note that, the remote may indeed
be sending an unlocked file, but sendkey uses sendAnnex, which will detect
if the file is modified before or during transfer, and will exit nonzero,
aborting the upload. So, the receiver doesn't need any checks.
In copyToRemote, it forces recvkey to verify content whenever it's being
sent from a v6 repository. recvkey is almost always going to verify content
anyway, unless annex.verify is not set. So, this doesn't make it any more
expensive, except for in that unusual configuration. The alternative would
be to change the recvkey interface, so that the sender checks afterwards if
what it was sending changed, and the receiver then throws out the bad
transfer. That would be less expensive for the reciever, as it would not
need to do a checksum verification. But, it would mean another network
round trip, and since rsync closes the connection, it would need to open
another ssh connection to do this. Even with connction caching, that would
add latency to uploads. It would also complicate the interface, especially
because an older git-annex-shell would not have the new interface
available. For these reasons, I prefer punting on that at this time, and
instead someone might set annex.verify=false and be unhappy that it still
verifies..
(One other gotcha not dealt with is that a v5 repo could be upgraded to v6
while an upload is in progress, and a file unlocked and modified.)
(Also, I double-checked Remote.GCrypt's calls to rsyncParamsRemote, and
they're fine. When a file is being uploaded to gcrypt, or any other special
repository, it is mediated by sendAnnex, so changes will be detected at
that level and the special remote implementation doesn't need to worry
about them.)
Had everything available, just didn't combine the progress meter with the
other places progress is sent to update it. (And to a remote repo already
did show progress.)
Most special remotes should already display progress meters with -J,
same as without it. One exception to this is the web, since it relies on
wget/curl progress display without -J. Still todo..
Instead, only display transport error if the configlist output doesn't
include an annex.uuid line, even an empty one.
A recent change made git-annex init try to get all the remote uuids, and so
the transport error would be displayed by it. It was also displayed when
eg, copying files to a remote that had no uuid yet.
/dev/null stderr; ssh is still able to display a password prompt
despite this
Show some messages so the user knows it's locking a remote, and
knows if that locking failed.
Also, rename lockContent to lockContentExclusive
inAnnexSafe should perhaps be eliminated, and instead use
`lockContentShared inAnnex`. However, I'm waiting on that, as there are
only 2 call sites for inAnnexSafe and it's fiddly.
In c6632ee5c8, it actually only handled
uploading objects to a shared repository. To avoid verification when
downloading objects from a shared repository, was a lot harder.
On the plus side, if the process of downloading a file from a remote
is able to verify its content on the side, the remote can indicate this
now, and avoid the extra post-download verification.
As of yet, I don't have any remotes (except Git) using this ability.
Some more work would be needed to support it in special remotes.
It would make sense for tahoe to implicitly verify things downloaded from it;
as long as you trust your tahoe server (which typically runs locally),
there's cryptographic integrity. OTOH, despite bup being based on shas,
a bup repo under an attacker's control could have the git ref used for an
object changed, and so a bup repo shouldn't implicitly verify. Indeed,
tahoe seems unique in being trustworthy enough to implicitly verify.
* When annex objects are received into git repositories, their checksums are
verified then too.
* To get the old, faster, behavior of not verifying checksums, set
annex.verify=false, or remote.<name>.annex-verify=false.
* setkey, rekey: These commands also now verify that the provided file
matches the key, unless annex.verify=false.
* reinject: Already verified content; this can now be disabled by
setting annex.verify=false.
recvkey and reinject already did verification, so removed now duplicate
code from them. fsck still does its own verification, which is ok since it
does not use getViaTmp, so verification doesn't happen twice when using fsck
--from.
Note that I had one in Annex.Action.startup too, but it resulted in a weird
message printed by ssh, "channel 2: bad ext data". I don't know why, but
it only happened when transferinfo was run, so I wonder
if 983a95f021 introduced a fragility somehow.
Now it suffices to run git remote add, followed by git-annex sync. Now the
remote is automatically initialized for use by git-annex, where before the
git-annex branch had to manually be pushed before using git-annex sync.
Note that this involved changes to git-annex-shell, so if the remote is
using an old version, the manual push is still needed.
Implementation required git-annex-shell be changed, so configlist can
autoinit a repository even when no git-annex branch has been pushed yet.
Unfortunate because we'll have to wait for it to get deployed to servers
before being able to rely on this change in the documentation.
Did consider making git-annex sync push the git-annex branch to repos that
didn't have a uuid, but this seemed difficult to do without complicating it
in messy ways.
It would be cleaner to split a command out from configlist to handle
the initialization. But this is difficult without sacrificing backwards
compatability, for users of old git-annex versions which would not use the
new command.
Only the assistant uses these, and only the assistant cleans them up, so
make only git annex transferkeys write them,
There is one behavior change from this. If glacier is being used, and a
manual git annex get --from glacier fails because the file isn't available
yet, the assistant will no longer later see that failed transfer file and
retry the get. Hope no-one depended on that old behavior.
The directory special remote was not affected in its normal configuration,
since annex-directory is an absolute path normally. But it could fail
when a relative path was used.
The git remote was affected even when an absolute path to it was used in
.git/config, since git-annex now converts all such paths to relative.
Most of the time, there will be no discreprancy between programPath and
readProgramFile.
But, the programFile might have been written by an old version of git-annex
that is still installed, while a newer one is currently running. In this
case, we want to run the same one that's currently running.
This is especially important for things like the GIT_SSH=git-annex used for
ssh connection caching.
The only code that still uses readProgramFile directly is the upgrade code,
which needs to know where the standalone git-annex was installed, in order to
upgrade it.
Avoid using fileSize which maxes out at just 2 gb on Windows.
Instead, use hFileSize, which doesn't have a bounded size.
Fixes support for files > 2 gb on Windows.
Note that the InodeCache code only needs to compare a file size,
so it doesn't matter it the file size wraps. So it has been
left as-is. This was necessary both to avoid invalidating existing inode
caches, and because the code passed FileStatus around and would have become
more expensive if it called getFileSize.
This commit was sponsored by Christian Dietrich.
* info: Can now display info about a given uuid.
* Added to remote/uuid info: Count of the number of keys present
on the remote, and their size. This is rather expensive to calculate,
so comes last and --fast will disable it.
* Git remote info now includes the date of the last sync with the remote.
Reverts 965e106f24
Unfortunately, this caused breakage on Windows, and possibly elsewhere,
because parentDir and takeDirectory do not behave the same when there is a
trailing directory separator.
parentDir is less safe than takeDirectory, especially when working
with relative FilePaths. It's really only useful in loops that
want to terminate at /
This commit was sponsored by Audric SCHILTKNECHT.
