FS_POSIX.createNewFile(File) failed to properly implement atomic file
creation on NFS using the algorithm [1]:
- name of the hard link must be unique to prevent that two processes
using different NFS clients try to create the same link. This would
render nlink useless to detect if there was a race.
- the hard link must be retained for the lifetime of the file since we
don't know when the state of the involved NFS clients will be
synchronized. This depends on NFS configuration options.
To fix these issues we need to change the signature of createNewFile
which would break API. Hence deprecate the old method
FS.createNewFile(File) and add a new method createNewFileAtomic(File).
The new method returns a LockToken which needs to be retained by the
caller (LockFile) until all involved NFS clients synchronized their
state. Since we don't know when the NFS caches are synchronized we need
to retain the token until the corresponding file is no longer needed.
The LockToken must be closed after the LockFile using it has been
committed or unlocked. On Posix, if core.supportsAtomicCreateNewFile =
false this will delete the hard link which guarded the atomic creation
of the file. When acquiring the lock fails ensure that the hard link is
removed.
[1] https://www.time-travellers.org/shane/papers/NFS_considered_harmful.html
also see file creation flag O_EXCL in
http://man7.org/linux/man-pages/man2/open.2.html
Change-Id: I84fcb16143a5f877e9b08c6ee0ff8fa4ea68a90d
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
When core.supportsAtomicCreateNewFile was set to false and the
repository was located on a filesystem which doesn't support the file
attribute "unix:nlink" then FS_POSIX#createNewFile may report an error
even if everything was ok. Modify FS_POSIX#createNewFile to silently
ignore this situation. An example of such a filesystem is sshfs where
reading "unix:nlink" always returns 1 (instead of throwing a exception).
Bug: 537969
Change-Id: I6deda7672fa7945efa8706ea1cd652272604ff19
Also-by: Thomas Wolf <thomas.wolf@paranor.ch>
I88304d34c and Ia555bce00 modified the way errors are handled when
trying to delete non-empty reference folders. Before, this error was
silently ignored as it was considered an expected output. Now, every
failed folder delete is logged which can be noisy.
Ignore the DirectoryNotEmptyException but log any other error avoiding
deletion of an eligible folder.
Signed-off-by: Hector Oswaldo Caballero <hector.caballero@ericsson.com>
Change-Id: I194512f67885231d62c03976ae683e5cc450ec7c
The following commits introduced in stable-4.5 and stable-4.9
introduced some minor API additions in service releases.
f7ceeaa2 FileRepository: Add pack-based inserter implementation
085d1f95 Make PackInserter public
10e65cb4 Fix LockFile semantics when running on NFS
Change-Id: I4afed7e0395cf93d828e671080e3ec9ddf20987d
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
This is actually a fairly common occurrence; deleting the parent
directories can work only if the file deleted was the last one
in the directory.
Bug: 537872
Change-Id: I86d1d45e1e2631332025ff24af8dfd46c9725711
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>
If packed refs are used, duplicate updates result in an exception
because JGit tries to lock the same lock file twice. With non-atomic
ref updates, this used to work, since the same ref would simply be
locked and updated twice in succession.
Let's be more lenient in this case and remove duplicates before
trying to do the ref updates. Silently skip duplicate updates
for the same ref, if they both would update the ref to the same
object ID. (If they don't, behavior is undefined anyway, and we
still throw an exception.)
Add a test that results in a duplicate ref update for a tag.
Bug: 529400
Change-Id: Ide97f20b219646ac24c22e28de0c194a29cb62a5
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>
Bug: 529314
Change-Id: I91eaeda8a988d4786908fba6de00478cfc47a2a2
Signed-off-by: Marc Strapetz <marc.strapetz@syntevo.com>
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>
Since I3870cadb4, GC task was always delegated to an executor even when
background option was set to false. This was an issue because if more
than one GC object was instantiated and executed in parallel, only one GC
was actually running because of the single thread executor.
Change-Id: I8c587d22d63c1601b7d75914692644a385cd86d6
Signed-off-by: Hugo Arès <hugo.ares@ericsson.com>
Remove completely the empty directories under refs/<namespace>
including the first level partition of the changes, when they are
completely empty.
Bug: 536777
Change-Id: I88304d34cc42435919c2d1480258684d993dfdca
Signed-off-by: Luca Milanesio <luca.milanesio@gmail.com>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
Get the full IOException of the reason why a directory
cannot be removed during GC.
Change-Id: Ia555bce009fa48087a73d677f1ce3b9c0b685b57
Signed-off-by: Luca Milanesio <luca.milanesio@gmail.com>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
After packaging references, the folders containing these references are
not deleted. In a busy repository, this causes operations to slow down
as traversing the references tree becomes longer.
Delete empty reference folders after the loose references have been
packed.
To avoid deleting a folder that was just created by another concurrent
operation, only delete folders that were not modified in the last 30
seconds.
Signed-off-by: Hector Oswaldo Caballero <hector.caballero@ericsson.com>
Change-Id: Ie79447d6121271cf5e25171be377ea396c7028e0
Signed-off-by: Luca Milanesio <luca.milanesio@gmail.com>
Signed-off-by: David Pursehouse <david.pursehouse@gmail.com>
Log as warning when an attempt to remove a directory
fails. This helps troubleshooting some bugs like the GC leaving
behind empty directories.
Change-Id: Idb94ce17f8be9668a970c7ecae31436bf434073c
Signed-off-by: Luca Milanesio <luca.milanesio@gmail.com>
This change fixes the issue [1]. Before this fix, a merge involving
the caching of consecutive yet similar filenames with Norwegian
characters [2] used to throw an IllegalStateException: Duplicate
stages not allowed. This was caused by inaccurate decoding of the
filenames, using string values assuming default encoding. In the
toString method of DirCacheEntry, used before through getPathString,
UTF-8 encoding is used, but the end result becomes default encoding,
through Object's default toString usage. The special characters in
those two consecutive (particular) filenames [2] were becoming the
very same decoded /single character, lending consecutive -but then
identical- filenames. Thus the perceived duplicate 0-staging of the
file(s).
Replace getPathString usage with getRawPath for this specific case,
or use byte array representations of cached entries instead of string.
Adding a test for this change is not possible, as there is no known
way to change the default encoding for filenames such as [2] (e.g.).
JGitTestUtil does write file contents through UTF-8, but encoding like
so does not apply to the actual file name. Hence there is no way to
create files with names properly made of special characters such as
[2]'s. And the test that is necessary for this case assumes such
Norwegian (or similar characters) filenames. Changing the default
locale programmatically in a test has no effect either. And changing
the LANG value passed to the JVM is only possible upon starting it.
[1] https://bugs.chromium.org/p/gerrit/issues/detail?id=9153
[2] <=>
(...)
"a/b/SíÒr-Norge.map",
"a/b/Sør-Norge.map",
(...)
Change-Id: Ib9f2f5297932337c9817064cc09d9f774dd168f4
Signed-off-by: Marco Miller <marco.miller@ericsson.com>
From the javadoc for Files.list:
"The returned stream encapsulates a DirectoryStream. If timely disposal
of file system resources is required, the try-with-resources construct
should be used to ensure that the stream's close method is invoked
after the stream operations are completed."
This is the only call to Files#newDirectoryStream that is not already in
a try-with-resources.
Change-Id: I91e6c56b5d74e8435457ad6ed9e6b4b24d2aa14e
(cherry picked from commit 1c16ea4601)
On a local non-NFS filesystem the .git/config file will be orphaned if
it is replaced by a new process while the current process is reading the
old file. The current process successfully continues to read the
orphaned file until it closes the file handle.
Since NFS servers do not keep track of open files, instead of orphaning
the old .git/config file, such a replacement on an NFS filesystem will
instead cause the old file to be garbage collected (deleted). A stale
file handle exception will be raised on NFS clients if the file is
garbage collected (deleted) on the server while it is being read. Since
we no longer have access to the old file in these cases, the previous
code would just fail. However, in these cases, reopening the file and
rereading it will succeed (since it will open the new replacement file).
Since retrying the read is a viable strategy to deal with stale file
handles on the .git/config file, implement such a strategy.
Since it is possible that the .git/config file could be replaced again
while rereading it, loop on stale file handle exceptions, up to 5 extra
times, trying to read the .git/config file again, until we either read
the new file, or find that the file no longer exists. The limit of 5 is
arbitrary, and provides a safe upper bounds to prevent infinite loops
consuming resources in a potential unforeseen persistent error
condition.
Change-Id: I6901157b9dfdbd3013360ebe3eb40af147a8c626
Signed-off-by: Nasser Grainawi <nasser@codeaurora.org>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
If we give Jsch access to the ssh config file, we must _not_ resolve
the host name from the alias. Instead we must give the alias (i.e.,
the host name as is in the URI) to Jsch, so that it finds the same
ssh config entry.
Otherwise if the hostname in the URI, which is taken as an alias in
ssh config ("Host" line), is unequal to the "Hostname" line, and
there happens to be another ssh config entry with that translated
host name as alias, Jsch will pick up that second entry, and we end
up with a strange mixture of both.
Add tests for this case.
Bug: 531118
Change-Id: I249d8c073b0190ed110a69dca5b9be2a749822c3
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>
Jsch unconditionally overwrites the port from the ssh config
file (if a port is specified there), even if the URI explicitly does
give a different port.
Fix this, and add tests.
Change-Id: I7b014543c7ece26270e366db39d7647f82d64f0d
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>
* Fix "can not" -> "cannot" in two messages
* Re-word "Cannot mkdir" to "Cannot create directory"
Change-Id: Ide0cec55eeeebd23bccc136257c80f47638ba858
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>
Jsch caches keys (aka identities) specified in ~/.ssh/config via
IndentityFile only for the current Jsch Session. This results in
multiple password prompts for successive sessions.
Do the handling of IdentityFile exclusively in JGit, as it was before
4.9. JGit uses different Jsch instances per host and caches the
IdentityFile there, allowing it to be re-used in different sessions
for the same host.
* Add comments to explain this.
* Move the JschBugFixingConfig from OpenSshConfig to
JschConfigSessionFactory to have all these Jsch work-arounds
in one place.
* Make that config hide the IdentityFile config from Jsch to avoid
that Jsch overrides the JGit behavior.
Bug: 529173
Change-Id: Ib36c34a2921ba736adeb64de71323c2b91151613
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>
Originally the patterns were escaped twice leading
to wrong matching results.
Bug: 528886
Change-Id: I26e201b4b0ef51cac08f940b76f381260fa925ca
Signed-off-by: Dmitry Pavlenko <pavlenko@tmatesoft.com>
Signed-off-by: David Pursehouse <david.pursehouse@gmail.com>
The intent with the setCompressionLevel and checkExisting methods (which
are already public) is for callers to be able to call them, but they
can't do that if the class itself is not public.
Change-Id: I014044fec3bfa1d33775500345efd60eb5d45bde
When interleaving reads and writes from an unflushed pack, we forgot to
reset the file pointer back to the end of the file before writing more
new objects. This had at least two unfortunate effects:
* The pack data was potentially corrupt, since we could overwrite
previous portions of the file willy-nilly.
* The CountingOutputStream would report more bytes read than the size
of the file, which stored the wrong PackedObjectInfo, which would
cause EOFs during reading.
We already had a test in PackInserterTest which was supposed to catch
bugs like this, by interleaving reads and writes. Unfortunately, it
didn't catch the bug, since as an implementation detail we always read a
full buffer's worth of data from the file when inflating during
readback. If the size of the file was less than the offset of the object
we were reading back plus one buffer (8192 bytes), we would completely
accidentally end up back in the right place in the file.
So, add another test for this case where we read back a small object
positioned before a large object. Before the fix, this test exhibited
exactly the "Unexpected EOF" error reported at crbug.com/gerrit/7668.
Change-Id: I74f08f3d5d9046781d59e5bd7c84916ff8225c3b
When we are cloning we have no refs at all yet, and there cannot
(or at least should not) be any other thread doing something with
refs yet.
Locking loose refs is thus not needed, since there are no loose
refs yet and nothing should be trying to create them concurrently.
Let's skip the whole loose ref locking when we are cloning a repository.
As a result, JGit will write the refs directly to the packed-refs
file, and will not create the refs/remotes/ directories nor the
lock files underneath when cloning and packed refs are used. Since
no lock files are created, any problems on case-insensitive file
systems with tag or branch names that differ only in case are avoided
during cloning.
Detect if we are cloning based on the following heuristics:
* HEAD is a dangling symref
* There is no loose ref
* There is no packed-refs file
Note, however, that there may still be problems with such tag or
branch names later on. This is primarily a five-minutes-past-twelve
stop-gap measure to resolve the referenced bug, which affects the
Oxygen.2 release.
Bug: 528497
Change-Id: I57860c29c210568165276a123b855e462b6a107a
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
The Config class must be safe to run against untrusted input files.
Reading arbitrary local system paths using include.path is risky for
servers, including Gerrit Code Review.
This was fixed on master [1] by making "readIncludedConfig" a noop
by default. This allows only FileBasedConfig, which originated from
local disk, to read local system paths.
However, the "readIncludedConfig" method was only introduced in [2]
which was needed by [3], both of which are only on the master branch.
On the stable branch only Config supports includes. Therefore this
commit simply disables the include functionality.
[1] https://git.eclipse.org/r/#/c/113371/
[2] https://git.eclipse.org/r/#/c/111847/
[3] https://git.eclipse.org/r/#/c/111848/
Bug: 528781
Change-Id: I9a3be3f1d07c4b6772bff535a2556e699a61381c
Signed-off-by: David Pursehouse <david.pursehouse@gmail.com>
FindBugs reports:
This class is an inner class, but does not use its embedded reference
to the object which created it. This reference makes the instances
of the class larger, and may keep the reference to the creator object
alive longer than necessary. If possible, the class should be made
static.
Change-Id: I9f49de32b4cd81b7ef1239b390353689263bf66e
Signed-off-by: David Pursehouse <david.pursehouse@gmail.com>
If some process executed by FS#readPipe lived for a while after
closing stderr, FS#GobblerThread#run failed with an
IllegalThreadStateException exception when accessing p.exitValue()
for the process which is still alive.
Add Process#waitFor calls to wait for the process completion.
Bug: 528335
Change-Id: I87e0b6f9ad0b995dbce46ddfb877e33eaf3ae5a6
Signed-off-by: Dmitry Pavlenko <pavlenko@tmatesoft.com>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
This was silenced before but suppression was unintentionally lost in
merge commit 6858339c1e.
This method was removed in 4.9.0 and reintroduced in 4.9.1 to avoid
breaking EMF compare versions which were built against older versions.
See: abf420302b
Change-Id: I152d58ac885e044bcab682b9423f6cc83b667989
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
When a GC operation is interrupted, temporary packs and indexes can be
left on the pack folder. In big, busy repositories this can lead to
significant amounts of wasted disk space if this interruption is done
with a certain frequency.
Remove stale temporary packs and indexes at the end of the GC process so
they do not accumulate. To avoid interfering with a possible concurrent
JGit GC process in the same repository, only delete temporary files that
are older than one day.
Change-Id: If9b6c1e57fac8a6a0ecc0a703089634caba4caae
Signed-off-by: Hector Caballero <hector.caballero@ericsson.com>
- this is a new warning option in Eclipse 4.7 and higher
- we always change version of all bundles in a release to keep release
engineering simple
Change-Id: Ic7523d77b67b2802f1bab3bc70af250d712a034f
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
When running on NFS there was a chance that JGits LockFile
semantic is broken because File#createNewFile() may allow
multiple clients to create the same file in parallel. This
change provides a fix which is only used when the new config
option core.supportsAtomicCreateNewFile is set to false. The
default for this option is true. This option can only be set in the
global or the system config file. The repository config file is not
taken into account in this case.
If the config option core.supportsAtomicCreateNewFile is true
then File#createNewFile() is trusted and the behaviour doesn't
change.
But if core.supportsAtomicCreateNewFile is set to false then after
successful creation of the lock file a hardlink to that lock file is
created and the attribute nlink of the lock file is checked to be 2. If
multiple clients manage to create the same lock file nlink would be
greater than 2 showing the error.
This expensive workaround is described in
https://www.time-travellers.org/shane/papers/NFS_considered_harmful.html
section III.d) "Exclusive File Creation"
Change-Id: I3d2cc48d8eb280d5f7039eb94da37804f903be6a
Then list of packed refs was cached in RefDirectory based on mtime of
the packed-refs file. This may fail on NFS when attributes are cached.
A cached mtime of the packed-refs file could cause JGit to trust the
cached content of this file and to overlook that the file is modified.
Honor the config option trustFolderStats and always read the packed-refs
content if the option is false. By default this option is set to true
and this fix is not active.
Change-Id: I2b65cfaa8f4aba2efbf8a5e865d3f09f927e2eec
Matthias Sohn
Christian Halstrick
Hector Caballero
Thomas Wolf
Marc Strapetz
Hugo Arès
Luca Milanesio
Marco Miller
Dave Borowitz
Nasser Grainawi
Dmitry Pavlenko
David Pursehouse
David Turner