t1450-fsck.sh does not have a test that checks fsck's behavior when a
packfile is invalid. It does have a test for when an object in a
packfile is invalid, but in that test, the packfile itself is valid.
Add such a test.
Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
GNU grep allows "\(A\|B\)" as alternation in BRE, but this is an
extension not understood by some other implementations of grep
(Michael Kebe reported an breakage on Solaris).
Rewrite the offending test to ERE and use egrep instead.
Noticed-by: Michael Kebe <michael.kebe@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The previous step added a path zzzzzzzz to the index, and then used
"sed" to replace this string to yyyyyyyy to create a test case where
the checksum at the end of the file does not match the contents.
Unfortunately, use of "sed" on a non-text file is not portable.
Instead, use a Perl script that seeks to the end and modifies the
last byte of the file (where we _know_ stores the trailing
checksum).
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Teach git to skip verification of the SHA1-1 checksum at the end of
the index file in verify_hdr() which is called from read_index()
unless the "force_verify_index_checksum" global variable is set.
Teach fsck to force this verification.
The checksum verification is for detecting disk corruption, and for
small projects, the time it takes to compute SHA-1 is not that
significant, but for gigantic repositories this calculation adds
significant time to every command.
These effect can be seen using t/perf/p0002-read-cache.sh:
Test HEAD~1 HEAD
--------------------------------------------------------------------------------------
0002.1: read_cache/discard_cache 1000 times 0.66(0.44+0.20) 0.30(0.27+0.02) -54.5%
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"git fsck --connectivity-check" was not working at all.
* jk/fsck-connectivity-check-fix:
fsck: lazily load types under --connectivity-only
fsck: move typename() printing to its own function
t1450: use "mv -f" within loose object directory
fsck: check HAS_OBJ more consistently
fsck: do not fallback "git fsck <bogus>" to "git fsck"
fsck: tighten error-checks of "git fsck <head>"
fsck: prepare dummy objects for --connectivity-check
fsck: report trees as dangling
t1450: clean up sub-objects in duplicate-entry test
The loose objects are created with mode 0444. That doesn't
prevent them being overwritten by rename(), but some
versions of "mv" will be extra careful and prompt the user,
even without "-i".
Reportedly macOS does this, at least in the Travis builds.
The prompt reads from /dev/null, defaulting to "no", and the
object isn't moved. Then to make matters even more
interesting, it still returns "0" and the rest of the test
proceeds, but with a broken setup.
We can work around it by using "mv -f" to override the
prompt. This should work as it's already used in t5504 for
the same purpose.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Since fsck tries to continue as much as it can after seeing
an error, we still do the reachability check even if some
heads we were given on the command-line are bogus. But if
_none_ of the heads is is valid, we fallback to checking all
refs and the index, which is not what the user asked for at
all.
Instead of checking "heads", the number of successful heads
we got, check "argc" (which we know only has non-options in
it, because parse_options removed the others).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Instead of checking reachability from the refs, you can ask
fsck to check from a particular set of heads. However, the
error checking here is quite lax. In particular:
1. It claims lookup_object() will report an error, which
is not true. It only does a hash lookup, and the user
has no clue that their argument was skipped.
2. When either the name or sha1 cannot be resolved, we
continue to exit with a successful error code, even
though we didn't check what the user asked us to.
This patch fixes both of these cases.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Normally fsck makes a pass over all objects to check their
integrity, and then follows up with a reachability check to
make sure we have all of the referenced objects (and to know
which ones are dangling). The latter checks for the HAS_OBJ
flag in obj->flags to see if we found the object in the
first pass.
Commit 02976bf85 (fsck: introduce `git fsck --connectivity-only`,
2015-06-22) taught fsck to skip the initial pass, and to
fallback to has_sha1_file() instead of the HAS_OBJ check.
However, it converted only one HAS_OBJ check to use
has_sha1_file(). But there are many other places in
builtin/fsck.c that assume that the flag is set (or that
lookup_object() will return an object at all). This leads to
several bugs with --connectivity-only:
1. mark_object() will not queue objects for examination,
so recursively following links from commits to trees,
etc, did nothing. I.e., we were checking the
reachability of hardly anything at all.
2. When a set of heads is given on the command-line, we
use lookup_object() to see if they exist. But without
the initial pass, we assume nothing exists.
3. When loading reflog entries, we do a similar
lookup_object() check, and complain that the reflog is
broken if the object doesn't exist in our hash.
So in short, --connectivity-only is broken pretty badly, and
will claim that your repository is fine when it's not.
Presumably nobody noticed for a few reasons.
One is that the embedded test does not actually test the
recursive nature of the reachability check. All of the
missing objects are still in the index, and we directly
check items from the index. This patch modifies the test to
delete the index, which shows off breakage (1).
Another is that --connectivity-only just skips the initial
pass for loose objects. So on a real repository, the packed
objects were still checked correctly. But on the flipside,
it means that "git fsck --connectivity-only" still checks
the sha1 of all of the packed objects, nullifying its
original purpose of being a faster git-fsck.
And of course the final problem is that the bug only shows
up when there _is_ corruption, which is rare. So anybody
running "git fsck --connectivity-only" proactively would
assume it was being thorough, when it was not.
One possibility for fixing this is to find all of the spots
that rely on HAS_OBJ and tweak them for the connectivity-only
case. But besides the risk that we might miss a spot (and I
found three already, corresponding to the three bugs above),
there are other parts of fsck that _can't_ work without a
full list of objects. E.g., the list of dangling objects.
Instead, let's make the connectivity-only case look more
like the normal case. Rather than skip the initial pass
completely, we'll do an abbreviated one that sets up the
HAS_OBJ flag for each object, without actually loading the
object data.
That's simple and fast, and we don't have to care about the
connectivity_only flag in the rest of the code at all.
While we're at it, let's make sure we treat loose and packed
objects the same (i.e., setting up dummy objects for both
and skipping the actual sha1 check). That makes the
connectivity-only check actually fast on a real repo (40
seconds versus 180 seconds on my copy of linux.git).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
After checking connectivity, fsck looks through the list of
any objects we've seen mentioned, and reports unreachable
and un-"used" ones as dangling. However, it skips any object
which is not marked as "parsed", as that is an object that
we _don't_ have (but that somebody mentioned).
Since 6e454b9a3 (clear parsed flag when we free tree
buffers, 2013-06-05), that flag can't be relied on, and the
correct method is to check the HAS_OBJ flag. The cleanup in
that commit missed this callsite, though. As a result, we
would generally fail to report dangling trees.
We never noticed because there were no tests in this area
(for trees or otherwise). Let's add some.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This test creates a multi-level set of trees, but its
cleanup routine only removes the top-level tree. After the
test finishes, the inner tree and the blob it points to
remain, making the inner tree dangling.
A later test ("cleaned up") verifies that we've removed any
cruft and "git fsck" output is clean. This passes only
because of a bug in git-fsck which fails to notice dangling
trees.
In preparation for fixing the bug, let's teach this earlier
test to clean up after itself correctly. We have to remove
the inner tree (and therefore the blob, too, which becomes
dangling after removing that tree).
Since the setup code happens inside a subshell, we can't
just set a variable for each object. However, we can stuff
all of the sha1s into the $T output variable, which is not
used for anything except cleanup.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When a loose tree or commit is read by fsck (or any git
program), unpack_sha1_rest() checks whether there is extra
cruft at the end of the object file, after the zlib data.
Blobs that are streamed, however, do not have this check.
For normal git operations, it's not a big deal. We know the
sha1 and size checked out, so we have the object bytes we
wanted. The trailing garbage doesn't affect what we're
trying to do.
But since the point of fsck is to find corruption or other
problems, it should be more thorough. This patch teaches its
loose-sha1 reader to detect extra bytes after the zlib
stream and complain.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When we iterate over the list of loose objects to check, we
get the actual path of each object. But we then throw it
away and pass just the sha1 to fsck_sha1(), which will do a
fresh lookup. Usually it would find the same object, but it
may not if an object exists both as a loose and a packed
object. We may end up checking the packed object twice, and
never look at the loose one.
In practice this isn't too terrible, because if fsck doesn't
complain, it means you have at least one good copy. But
since the point of fsck is to look for corruption, we should
be thorough.
The new read_loose_object() interface can help us get the
data from disk, and then we replace parse_object() with
parse_object_buffer(). As a bonus, our error messages now
mention the path to a corrupted object, which should make it
easier to track down errors when they do happen.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The code paths in fsck for packed and loose objects are
quite different, and it is not immediately obvious that the
packed case behaves well. In particular:
1. The fsck_loose() function always returns "0" to tell the
iterator to keep checking more objects. Whereas
fsck_obj_buffer() (which handles packed objects)
returns -1. This is OK, because the callback machinery
for verify_pack() does not stop when it sees a non-zero
return.
2. The fsck_loose() function sets the ERROR_OBJECT bit
when fsck_obj() fails, whereas fsck_obj_buffer() sets it
only when it sees a corrupt object. This turns out not
to matter. We don't actually do anything with this bit
except exit the program with a non-zero code, and that
is handled already by the non-zero return from the
function.
So there are no bugs here, but it was certainly confusing to
me. And we do not test either of the properties in t1450
(neither that a non-corruption error will caused a non-zero
exit for a packed object, nor that we keep going after
seeing the first error). Let's test both of those
conditions, so that we'll notice if any of those assumptions
becomes invalid.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When we fail to open a corrupt loose object, we report an
error and mention the filename via sha1_file_name().
However, that function will always give us a path in the
local repository, whereas the corrupt object may have come
from an alternate. The result is a very misleading error
message.
Teach the open_sha1_file() and stat_sha1_file() helpers to
pass back the path they found, so that we can report it
correctly.
Note that the pointers we return go to static storage (e.g.,
from sha1_file_name()), which is slightly dangerous.
However, these helpers are static local helpers, and the
names are used for immediately generating error messages.
The simplicity is an acceptable tradeoff for the danger.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Commit 90cf590f5 (fsck: optionally show more helpful info
for broken links, 2016-07-17) added a remove_loose_object()
helper, but we already had a remove_object() helper that did
the same thing. Let's combine these into one.
The implementations had a few subtle differences, so I've
tried to take the best of both:
- the original used "sed", but the newer version avoids
spawning an extra process
- the original processed "$*", which was nonsense, as it
assumed only a single sha1. Use "$1" to make that more
clear.
- the newer version ran an extra rev-parse, but it was not
necessary; it's sole caller already converted the
argument into a raw sha1
- the original used "rm -f", whereas the new one uses
"rm". The latter is better because it may notice a bug
or other unexpected failure in the test. (The original
does check that the object exists before we remove it,
which is good, but that's a subset of the possible
unexpected conditions).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Instead of dying when fsck hits a malformed tree object, log the error
like any other and continue. Now fsck can tell the user which tree is
bad, too.
Signed-off-by: David Turner <dturner@twosigma.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When reporting broken links between commits/trees/blobs, it would be
quite helpful at times if the user would be told how the object is
supposed to be reachable.
With the new --name-objects option, git-fsck will try to do exactly
that: name the objects in a way that shows how they are reachable.
For example, when some reflog got corrupted and a blob is missing that
should not be, the user might want to remove the corresponding reflog
entry. This option helps them find that entry: `git fsck` will now
report something like this:
broken link from tree b5eb6ff... (refs/stash@{<date>}~37:)
to blob ec5cf80...
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Even though a Git commit object is designed to be capable of storing
any binary data as its payload, in practice people use it to describe
the changes in textual form, and tools like "git log" are designed to
treat the payload as text.
Detect and warn when we see any commit object with a NUL byte in
it.
Note that a NUL byte in the header part is already detected as a
grave error. This change is purely about the message part.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We check the return value of verify_header() for commits already, so do
the same for tags as well.
Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Jeff King <peff@peff.net>
There were some classes of errors that "git fsck" diagnosed to its
standard error that did not cause it to exit with non-zero status.
* jc/fsck-dropped-errors:
fsck: exit with non-zero when problems are found
After finding some problems (e.g. a ref refs/heads/X points at an
object that is not a commit) and issuing an error message, the
program failed to signal the fact that it found an error by a
non-zero exit status.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This option avoids unpacking each and all blob objects, and just
verifies the connectivity. In particular with large repositories, this
speeds up the operation, at the expense of missing corrupt blobs,
ignoring unreachable objects and other fsck issues, if any.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We already have support in `git receive-pack` to deal with some legacy
repositories which have non-fatal issues.
Let's make `git fsck` itself useful with such repositories, too, by
allowing users to ignore known issues, or at least demote those issues
to mere warnings.
Example: `git -c fsck.missingEmail=ignore fsck` would hide
problems with missing emails in author, committer and tagger lines.
In the same spirit that `git receive-pack`'s usage of the fsck machinery
differs from `git fsck`'s – some of the non-fatal warnings in `git fsck`
are fatal with `git receive-pack` when receive.fsckObjects = true, for
example – we strictly separate the fsck.<msg-id> from the
receive.fsck.<msg-id> settings.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Some repositories written by legacy code have objects with non-fatal
fsck issues. To allow the user to ignore those issues, let's print
out the ID (e.g. when encountering "missingEmail", the user might
want to call `git config --add receive.fsck.missingEmail=warn`).
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Our is_hfs_dotgit function relies on the hackily-implemented
next_hfs_char to give us the next character that an HFS+
filename comparison would look at. It's hacky because it
doesn't implement the full case-folding table of HFS+; it
gives us just enough to see if the path matches ".git".
At the end of next_hfs_char, we use tolower() to convert our
32-bit code point to lowercase. Our tolower() implementation
only takes an 8-bit char, though; it throws away the upper
24 bits. This means we can't have any false negatives for
is_hfs_dotgit. We only care about matching 7-bit ASCII
characters in ".git", and we will correctly process 'G' or
'g'.
However, we _can_ have false positives. Because we throw
away the upper bits, code point \u{0147} (for example) will
look like 'G' and get downcased to 'g'. It's not known
whether a sequence of code points whose truncation ends up
as ".git" is meaningful in any language, but it does not
hurt to be more accurate here. We can just pass out the full
32-bit code point, and compare it manually to the upper and
lowercase characters we care about.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
New tag object format validation added in 2.2 showed garbage
after a tagname it reported in its error message.
* js/fsck-tag-validation:
index-pack: terminate object buffers with NUL
fsck: properly bound "invalid tag name" error message
Now that the index can block pathnames that can be mistaken
to mean ".git" on NTFS and FAT32, it would be helpful for
fsck to notice such problematic paths. This lets servers
which use receive.fsckObjects block them before the damage
spreads.
Note that the fsck check is always on, even for systems
without core.protectNTFS set. This is technically more
restrictive than we need to be, as a set of users on ext4
could happily use these odd filenames without caring about
NTFS.
However, on balance, it's helpful for all servers to block
these (because the paths can be used for mischief, and
servers which bother to fsck would want to stop the spread
whether they are on NTFS themselves or not), and hardly
anybody will be affected (because the blocked names are
variants of .git or git~1, meaning mischief is almost
certainly what the tree author had in mind).
Ideally these would be controlled by a separate
"fsck.protectNTFS" flag. However, it would be much nicer to
be able to enable/disable _any_ fsck flag individually, and
any scheme we choose should match such a system. Given the
likelihood of anybody using such a path in practice, it is
not unreasonable to wait until such a system materializes.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Now that the index can block pathnames that case-fold to
".git" on HFS+, it would be helpful for fsck to notice such
problematic paths. This lets servers which use
receive.fsckObjects block them before the damage spreads.
Note that the fsck check is always on, even for systems
without core.protectHFS set. This is technically more
restrictive than we need to be, as a set of users on ext4
could happily use these odd filenames without caring about
HFS+.
However, on balance, it's helpful for all servers to block
these (because the paths can be used for mischief, and
servers which bother to fsck would want to stop the spread
whether they are on HFS+ themselves or not), and hardly
anybody will be affected (because the blocked names are
variants of .git with invisible Unicode code-points mixed
in, meaning mischief is almost certainly what the tree
author had in mind).
Ideally these would be controlled by a separate
"fsck.protectHFS" flag. However, it would be much nicer to
be able to enable/disable _any_ fsck flag individually, and
any scheme we choose should match such a system. Given the
likelihood of anybody using such a path in practice, it is
not unreasonable to wait until such a system materializes.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We complain about ".git" in a tree because it cannot be
loaded into the index or checked out. Since we now also
reject ".GIT" case-insensitively, fsck should notice the
same, so that errors do not propagate.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We check that fsck notices and complains about confusing
paths in trees. However, there are a few shortcomings:
1. We check only for these paths as file entries, not as
intermediate paths (so ".git" and not ".git/foo").
2. We check "." and ".." together, so it is possible that
we notice only one and not the other.
3. We repeat a lot of boilerplate.
Let's use some loops to be more thorough in our testing, and
still end up with shorter code.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When we detect an invalid tag-name header in a tag object,
like, "tag foo bar\n", we feed the pointer starting at "foo
bar" to a printf "%s" formatter. This shows the name, as we
want, but then it keeps printing the rest of the tag buffer,
rather than stopping at the end of the line.
Our tests did not notice because they look only for the
matching line, but the bug is that we print much more than
we wanted to. So we also adjust the test to be more exact.
Note that when fscking tags with "index-pack --strict", this
is even worse. index-pack does not add a trailing
NUL-terminator after the object, so we may actually read
past the buffer and print uninitialized memory. Running
t5302 with valgrind does notice the bug for that reason.
Signed-off-by: Jeff King <peff@peff.net>
Acked-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Using "hash-object --literally", test one of the new breakages
js/fsck-tag-validation topic teaches "fsck" to catch is caught.
* jc/hash-object-fsck-tag:
t1450: make sure fsck detects a malformed tagger line
Teach "git fsck" to inspect the contents of annotated tag objects.
* js/fsck-tag-validation:
Make sure that index-pack --strict checks tag objects
Add regression tests for stricter tag fsck'ing
fsck: check tag objects' headers
Make sure fsck_commit_buffer() does not run out of the buffer
fsck_object(): allow passing object data separately from the object itself
Refactor type_from_string() to allow continuing after detecting an error
With "hash-object --literally", write a tag object that is not
supposed to pass one of the new checks added to "fsck", and make
sure that the new check catches the breakage.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Fsck tries hard to detect missing objects, and will complain
(and exit non-zero) about any inter-object links that are
missing. However, it will not exit non-zero for any missing
ref tips, meaning that a severely broken repository may
still pass "git fsck && echo ok".
The problem is that we use for_each_ref to iterate over the
ref tips, which hides broken tips. It does at least print an
error from the refs.c code, but fsck does not ever see the
ref and cannot note the problem in its exit code. We can solve
this by using for_each_rawref and noting the error ourselves.
In addition to adding tests for this case, we add tests for
all types of missing-object links (all of which worked, but
which we were not testing).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The intent of the new test case is to catch general breakages in
the fsck_tag() function, not so much to test it extensively, trying to
strike the proper balance between thoroughness and speed.
While it *would* have been nice to test the code path where fsck_object()
encounters an invalid tag object, this is not possible using git fsck: tag
objects are parsed already before fsck'ing (and the parser already fails
upon such objects).
Even worse: we would not even be able write out invalid tag objects
because git hash-object parses those objects, too, unless we resorted to
really ugly hacks such as using something like this in the unit tests
(essentially depending on Perl *and* Compress::Zlib):
hash_invalid_object () {
contents="$(printf '%s %d\0%s' "$1" ${#2} "$2")" &&
sha1=$(echo "$contents" | test-sha1) &&
suffix=${sha1#??} &&
mkdir -p .git/objects/${sha1%$suffix} &&
echo "$contents" |
perl -MCompress::Zlib -e 'undef $/; print compress(<>)' \
> .git/objects/${sha1%$suffix}/$suffix &&
echo $sha1
}
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Upon finding a corrupt loose object, we forgot to note the error to
signal it with the exit status of the entire process.
[jc: adjusted t1450 and added another test]
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When we check commit objects, we complain if commit->date is
ULONG_MAX, which is an indication that we saw integer
overflow when parsing it. However, we do not do any check at
all for author lines, which also contain a timestamp.
Let's actually check the timestamps on each ident line
with strtoul. This catches both author and committer lines,
and we can get rid of the now-redundant commit->date check.
Note that like the existing check, we compare only against
ULONG_MAX. Now that we are calling strtoul at the site of
the check, we could be slightly more careful and also check
that errno is set to ERANGE. However, this will make further
refactoring in future patches a little harder, and it
doesn't really matter in practice.
For 32-bit systems, one would have to create a commit at the
exact wrong second in 2038. But by the time we get close to
that, all systems will hopefully have moved to 64-bit (and
if they haven't, they have a real problem one second later).
For 64-bit systems, by the time we get close to ULONG_MAX,
all systems will hopefully have been consumed in the fiery
wrath of our expanding Sun.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Having a ".git" entry inside a tree can cause confusing
results on checkout. At the top-level, you could not
checkout such a tree, as it would complain about overwriting
the real ".git" directory. In a subdirectory, you might
check it out, but performing operations in the subdirectory
would confusingly consider the in-tree ".git" directory as
the repository.
The regular git tools already make it hard to accidentally
add such an entry to a tree, and do not allow such entries
to enter the index at all. Teaching fsck about it provides
an additional safety check, and let's us avoid propagating
any such bogosity when transfer.fsckObjects is on.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
A tree with meta-paths like '.' or '..' does not work well
with git; the index will refuse to load it or check it out
to the filesystem (and even if we did not have that safety,
it would look like we were overwriting an untracked
directory). For the same reason, it is difficult to create
such a tree with regular git.
Let's warn about these dubious entries during fsck, just in
case somebody has created a bogus tree (and this also lets
us prevent them from propagating when transfer.fsckObjects
is set).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
