If there is no worktree at present, we can still hint the user about
Git's current directory by showing them the absolute path to the Git
directory. Even though the Git directory doesn't make it as easy to
locate the worktree in question, it can still help a user figure out
what's going on while developing a script.
This fixes a segmentation fault introduced in e0020b2f
("prefix_path: show gitdir when arg is outside repo", 2020-02-14).
Signed-off-by: Emily Shaffer <emilyshaffer@google.com>
[jc: added minimum tests, with help from Szeder Gábor]
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The credential protocol can't handle values with newlines. We already
detect and block any such URLs from being used with credential helpers,
but let's also add an fsck check to detect and block gitmodules files
with such URLs. That will let us notice the problem earlier when
transfer.fsckObjects is turned on. And in particular it will prevent bad
objects from spreading, which may protect downstream users running older
versions of Git.
We'll file this under the existing gitmodulesUrl flag, which covers URLs
with option injection. There's really no need to distinguish the exact
flaw in the URL in this context. Likewise, I've expanded the description
of t7416 to cover all types of bogus URLs.
The credential protocol can't represent newlines in values, but URLs can
embed percent-encoded newlines in various components. A previous commit
taught the low-level writing routines to die() when encountering this,
but we can be a little friendlier to the user by detecting them earlier
and handling them gracefully.
This patch teaches credential_from_url() to notice such components,
issue a warning, and blank the credential (which will generally result
in prompting the user for a username and password). We blank the whole
credential in this case. Another option would be to blank only the
invalid component. However, we're probably better off not feeding a
partially-parsed URL result to a credential helper. We don't know how a
given helper would handle it, so we're better off to err on the side of
matching nothing rather than something unexpected.
The die() call in credential_write() is _probably_ impossible to reach
after this patch. Values should end up in credential structs only by URL
parsing (which is covered here), or by reading credential protocol input
(which by definition cannot read a newline into a value). But we should
definitely keep the low-level check, as it's our final and most accurate
line of defense against protocol injection attacks. Arguably it could
become a BUG(), but it probably doesn't matter much either way.
Note that the public interface of credential_from_url() grows a little
more than we need here. We'll use the extra flexibility in a future
patch to help fsck catch these cases.
The credential tests have a "check" function which feeds some input to
git-credential and checks the stdout and stderr. We look for exact
matches in the output. For stdout, this makes sense; the output is
the credential protocol. But for stderr, we may be showing various
diagnostic messages, or the prompts fed to the askpass program, which
could be translated. Let's mark them as such.
The credential protocol that we use to speak to helpers can't represent
values with newlines in them. This was an intentional design choice to
keep the protocol simple, since none of the values we pass should
generally have newlines.
However, if we _do_ encounter a newline in a value, we blindly transmit
it in credential_write(). Such values may break the protocol syntax, or
worse, inject new valid lines into the protocol stream.
The most likely way for a newline to end up in a credential struct is by
decoding a URL with a percent-encoded newline. However, since the bug
occurs at the moment we write the value to the protocol, we'll catch it
there. That should leave no possibility of accidentally missing a code
path that can trigger the problem.
At this level of the code we have little choice but to die(). However,
since we'd not ever expect to see this case outside of a malicious URL,
that's an acceptable outcome.
Reported-by: Felix Wilhelm <fwilhelm@google.com>
When a mergetag names a non-parent, which can occur after a shallow
clone, its hash was previously printed as raw data. Print it in hex form
instead.
Signed-off-by: Harald van Dijk <harald@gigawatt.nl>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This reverts commit 72b006f4bf, which
breaks the end-user experience when merging a signed tag without
having the public key. We should report "can't check because we
have no public key", but the code with this change claimed that
there was no signature.
Explanation
-----------
The problem here is flawed `poll()` implementation. When it tries to
see if pipe can be written without blocking, it eventually calls
`NtQueryInformationFile()` and tests `WriteQuotaAvailable`. However,
the meaning of quota was misunderstood. The value of quota is reduced
when either some data was written to a pipe, *or* there is a pending
read on the pipe. Therefore, if there is a pending read of size >= than
the pipe's buffer size, poll() will think that pipe is not writable and
will hang forever, usually that means deadlocking both pipe users.
I have studied the problem and found that Windows pipes track two values:
`QuotaUsed` and `BytesInQueue`. The code in `poll()` apparently wants to
know `BytesInQueue` instead of quota. Unfortunately, `BytesInQueue` can
only be requested from read end of the pipe, while `poll()` receives
write end.
The git's implementation of `poll()` was copied from gnulib, which also
contains a flawed implementation up to today.
I also had a look at implementation in cygwin, which is also broken in a
subtle way. It uses this code in `pipe_data_available()`:
fpli.WriteQuotaAvailable = (fpli.OutboundQuota - fpli.ReadDataAvailable)
However, `ReadDataAvailable` always returns 0 for the write end of the pipe,
turning the code into an obfuscated version of returning pipe's total
buffer size, which I guess will in turn have `poll()` always say that pipe
is writable. The commit that introduced the code doesn't say anything about
this change, so it could be some debugging code that slipped in.
These are the typical sizes used in git:
0x2000 - default read size in `strbuf_read()`
0x1000 - default read size in CRT, used by `strbuf_getwholeline()`
0x2000 - pipe buffer size in compat\mingw.c
As a consequence, as soon as child process uses `strbuf_read()`,
`poll()` in parent process will hang forever, deadlocking both
processes.
This results in two observable behaviors:
1) If parent process begins sending STDIN quickly (and usually that's
the case), then first `poll()` will succeed and first block will go
through. MAX_IO_SIZE_DEFAULT is 8MB, so if STDIN exceeds 8MB, then
it will deadlock.
2) If parent process waits a little bit for any reason (including OS
scheduler) and child is first to issue `strbuf_read()`, then it will
deadlock immediately even on small STDINs.
The problem is illustrated by `git stash push`, which will currently
read the entire patch into memory and then send it to `git apply` via
STDIN. If patch exceeds 8MB, git hangs on Windows.
Possible solutions
------------------
1) Somehow obtain `BytesInQueue` instead of `QuotaUsed`
I did a pretty thorough search and didn't find any ways to obtain
the value from write end of the pipe.
2) Also give read end of the pipe to `poll()`
That can be done, but it will probably invite some dirty code,
because `poll()`
* can accept multiple pipes at once
* can accept things that are not pipes
* is expected to have a well known signature.
3) Make `poll()` always reply "writable" for write end of the pipe
Afterall it seems that cygwin (accidentally?) does that for years.
Also, it should be noted that `pump_io_round()` writes 8MB blocks,
completely ignoring the fact that pipe's buffer size is only 8KB,
which means that pipe gets clogged many times during that single
write. This may invite a deadlock, if child's STDERR/STDOUT gets
clogged while it's trying to deal with 8MB of STDIN. Such deadlocks
could be defeated with writing less than pipe's buffer size per
round, and always reading everything from STDOUT/STDERR before
starting next round. Therefore, making `poll()` always reply
"writable" shouldn't cause any new issues or block any future
solutions.
4) Increase the size of the pipe's buffer
The difference between `BytesInQueue` and `QuotaUsed` is the size
of pending reads. Therefore, if buffer is bigger than size of reads,
`poll()` won't hang so easily. However, I found that for example
`strbuf_read()` will get more and more hungry as it reads large inputs,
eventually surpassing any reasonable pipe buffer size.
Chosen solution
---------------
Make `poll()` always reply "writable" for write end of the pipe.
Hopefully one day someone will find a way to implement it properly.
Reproduction
------------
printf "%8388608s" X >large_file.txt
git stash push --include-untracked -- large_file.txt
I have decided not to include this as test to avoid slowing down the
test suite. I don't expect the specific problem to come back, and
chances are that `git stash push` will be reworked to avoid sending the
entire patch via STDIN.
Signed-off-by: Alexandr Miloslavskiy <alexandr.miloslavskiy@syntevo.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We seem to be getting new users who get confused every 20 months or
so with this "-h consistently wants to give help, but the commands
to which `-h` may feel like a good short-form option want it to mean
something else." compromise.
Let's make sure that the readers know that `git cmd -h` (with no
other arguments) is a way to get usage text, even for commands like
ls-remote and grep.
Also extend the description that is already in gitcli.txt, as it is
clear that users still get confused with the current text.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The most recent Azure Pipelines macOS agents enable what Apple calls
"System Integrity Protection". This makes `p4d -V` hang: there is some
sort of GUI dialog waiting for the user to acknowledge that the copied
binaries are legit and may be executed, but on build agents, there is no
user who could acknowledge that.
Let's ask Homebrew specifically to _not_ quarantine the Perforce
binaries.
Helped-by: Aleksandr Chebotov
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Among other differences relative to GNU sed, macOS' sed always ends its
output with a trailing newline, even if the input did not have such a
trailing newline.
Surprisingly, this makes three httpd-based tests fail on macOS: t5616,
t5702 and t5703. ("Surprisingly" because those tests have been around
for some time, but apparently nobody runs them on macOS with a working
Apache2 setup.)
The reason is that we use `sed` in those tests to filter the response of
the web server. Apart from the fact that we use GNU constructs (such as
using a space after the `c` command instead of a backslash and a
newline), we have another problem: macOS' sed LF-only newlines while
webservers are supposed to use CR/LF ones.
Even worse, t5616 uses `sed` to replace a binary part of the response
with a new binary part (kind of hoping that the replaced binary part
does not contain a 0x0a byte which would be interpreted as a newline).
To that end, it calls on Perl to read the binary pack file and
hex-encode it, then calls on `sed` to prefix every hex digit pair with a
`\x` in order to construct the text that the `c` statement of the `sed`
invocation is supposed to insert. So we call Perl and sed to construct a
sed statement. The final nail in the coffin is that macOS' sed does not
even interpret those `\x<hex>` constructs.
Let's just replace all of that by Perl snippets. With Perl, at least, we
do not have to deal with GNU vs macOS semantics, we do not have to worry
about unwanted trailing newlines, and we do not have to spawn commands
to construct arguments for other commands to be spawned (i.e. we can
avoid a whole lot of shell scripting complexity).
The upshot is that this fixes t5616, t5702 and t5703 on macOS with
Apache2.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When using partial clone, find_non_local_tags() in builtin/fetch.c
checks each remote tag to see if its object also exists locally. There
is no expectation that the object exist locally, but this function
nevertheless triggers a lazy fetch if the object does not exist. This
can be extremely expensive when asking for a commit, as we are
completely removed from the context of the non-existent object and
thus supply no "haves" in the request.
6462d5eb9a (fetch: remove fetch_if_missing=0, 2019-11-05) removed a
global variable that prevented these fetches in favor of a bitflag.
However, some object existence checks were not updated to use this flag.
Update find_non_local_tags() to use OBJECT_INFO_SKIP_FETCH_OBJECT in
addition to OBJECT_INFO_QUICK. The _QUICK option only prevents
repreparing the pack-file structures. We need to be extremely careful
about supplying _SKIP_FETCH_OBJECT when we expect an object to not exist
due to updated refs.
This resolves a broken test in t5616-partial-clone.sh.
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
While testing partial clone, I noticed some odd behavior. I was testing
a way of running 'git init', followed by manually configuring the remote
for partial clone, and then running 'git fetch'. Astonishingly, I saw
the 'git fetch' process start asking the server for multiple rounds of
pack-file downloads! When tweaking the situation a little more, I
discovered that I could cause the remote to hang up with an error.
Add two tests that demonstrate these two issues.
In the first test, we find that when fetching with blob filters from
a repository that previously did not have any tags, the 'git fetch
--tags origin' command fails because the server sends "multiple
filter-specs cannot be combined". This only happens when using
protocol v2.
In the second test, we see that a 'git fetch origin' request with
several ref updates results in multiple pack-file downloads. This must
be due to Git trying to fault-in the objects pointed by the refs. What
makes this matter particularly nasty is that this goes through the
do_oid_object_info_extended() method, so there are no "haves" in the
negotiation. This leads the remote to send every reachable commit and
tree from each new ref, providing a quadratic amount of data transfer!
This test is fixed if we revert 6462d5eb9a (fetch: remove
fetch_if_missing=0, 2019-11-05), but that revert causes other test
failures. The real fix will need more care.
The tests are ordered in this way because if I swap the test order the
tag test will succeed instead of fail. I believe this is because somehow
we need the srv.bare repo to not have any tags when we clone, but then
have tags in our next fetch.
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
An accidental conversion of a tab to 4 spaces snuck into 4c4066d95d
(run-command: move doc to run-command.h, 2019-11-17), messing up the
alignment when you have the project-recommended 8-width tabstops. Let's
revert that line.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
If we need to delete a higher stage entry in the index to place the file
at stage 0, then we'll lose that file's stat information. In such
situations we may still be able to detect that the file on disk is the
version we want (as noted by our comment in the code:
/* do not overwrite file if already present */
), but we do still need to update the mtime since we are creating a new
cache_entry for that file. Update the logic used to determine whether
we refresh a file's mtime.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
A user discovered a case where they had a stack of 20 simple commits to
rebase, and the rebase would succeed in picking the first commit and
then error out with a pair of "Could not execute the todo command" and
"Your local changes to the following files would be overwritten by
merge" messages.
Their steps actually made use of the -i flag, but I switched it over to
-m to make it simpler to trigger the bug. With that flag, it bisects
back to commit 68aa495b59 (rebase: implement --merge via the
interactive machinery, 2018-12-11), but that's misleading. If you
change the -m flag to --keep-empty, then the problem persists and will
bisect back to 356ee4659b (sequencer: try to commit without forking
'git commit', 2017-11-24)
After playing with the testcase for a bit, I discovered that added
--exec "sleep 1" to the command line makes the rebase succeed, making me
suspect there is some kind of discard and reloading of caches that lead
us to believe that something is stat dirty, but I didn't succeed in
digging any further than that.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
check-ignore has two different modes, and neither of these modes has an
implementation that matches the documentation. These modes differ in
whether they just print paths or whether they also print the final
pattern matched by the path. The fix is different for both modes, so
I'll discuss both separately.
=== First (default) mode ===
The first mode is documented as:
For each pathname given via the command-line or from a file via
--stdin, check whether the file is excluded by .gitignore (or other
input files to the exclude mechanism) and output the path if it is
excluded.
However, it fails to do this because it did not account for negated
patterns. Commands other than check-ignore verify exclusion rules via
calling
... -> treat_one_path() -> is_excluded() -> last_matching_pattern()
while check-ignore has a call path of the form:
... -> check_ignore() -> last_matching_pattern()
The fact that the latter does not include the call to is_excluded()
means that it is susceptible to to messing up negated patterns (since
that is the only significant thing is_excluded() adds over
last_matching_pattern()). Unfortunately, we can't make it just call
is_excluded(), because the same codepath is used by the verbose mode
which needs to know the matched pattern in question. This brings us
to...
=== Second (verbose) mode ===
The second mode, known as verbose mode, references the first in the
documentation and says:
Also output details about the matching pattern (if any) for each
given pathname. For precedence rules within and between exclude
sources, see gitignore(5).
The "Also" means it will print patterns that match the exclude rules as
noted for the first mode, and also print which pattern matches. Unless
more information is printed than just pathname and pattern (which is not
done), this definition is somewhat ill-defined and perhaps even
self-contradictory for negated patterns: A path which matches a negated
exclude pattern is NOT excluded and thus shouldn't be printed by the
former logic, while it certainly does match one of the explicit patterns
and thus should be printed by the latter logic.
=== Resolution ==
Since the second mode exists to find out which pattern matches given
paths, and showing the user a pattern that begins with a '!' is
sufficient for them to figure out whether the pattern is excluded, the
existing behavior is desirable -- we just need to update the
documentation to match the implementation (i.e. it is about printing
which pattern is matched by paths, not about showing which paths are
excluded).
For the first or default mode, users just want to know whether a pattern
is excluded. As such, the existing documentation is desirable; change
the implementation to match the documented behavior.
Finally, also adjust a few tests in t0008 that were caught up by this
discrepancy in how negated paths were handled.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When rendering the troff manpages to text via "man", we create an ad-hoc
Makefile and feed it to "make". The purpose here is two-fold:
- reuse results from a prior interrupted render of the same tree
- use make's -j option to build in parallel
But the second part doesn't seem to work (at least with my version of
GNU make, 4.2.1). It just runs one render at a time.
We use a double-colon "all" rule for each file, like:
all:: foo
foo:
...actual render recipe...
all:: bar
bar:
...actual render recipe...
...and so on...
And it's this double-colon that seems to inhibit the parallelism. We can
just switch to a regular single-colon rule. Even though we do have
multiple rules for "all" here, we don't have any recipe to execute for
"all" (we only care about triggering its dependencies), so the
distinction is irrelevant.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The example for the push.pushOption config tries to create a
preformatted section, but uses only two dashes in its "--" line. In
AsciiDoc this is an "open block", with no type; the lines end up jumbled
because they're formatted as paragraphs. We need four or more dashes to
make it a "listing block" that will respect the linebreaks.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When developing a script, it can be painful to understand why Git thinks
something is outside the current repo, if the current repo isn't what
the user thinks it is. Since this can be tricky to diagnose, especially
in cases like submodules or nested worktrees, let's give the user a hint
about which repository is offended about that path.
Signed-off-by: Emily Shaffer <emilyshaffer@google.com>
Acked-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The details of how credential helpers can be called or implemented were
originally covered in Documentation/technical/. Those are topics that
end users might care about (and we even referenced them in the
credentials manpage), but those docs typically don't ship as part of the
end user documentation, making them less useful.
This situation got slightly worse recently in f3b9055624 (credential:
move doc to credential.h, 2019-11-17), where we moved them into the C
header file, making them even harder to find.
So let's move put this information into the gitcredentials(7)
documentation, which is meant to describe the overall concepts of our
credential handling. This was already pointing to the API docs for these
concepts, so we can just include it inline instead.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Technical details of the bundle format has been documented.
I think this is in a good enough shape.
* ms/doc-bundle-format:
doc: describe Git bundle format
"git grep --no-index" should not get affected by the contents of
the .gitmodules file but when "--recurse-submodules" is given or
the "submodule.recurse" variable is set, it did. Now these
settings are ignored in the "--no-index" mode.
* pb/do-not-recurse-grep-no-index:
grep: ignore --recurse-submodules if --no-index is given
Corner case bugs in "git clean" that stems from a (necessarily for
performance reasons) awkward calling convention in the directory
enumeration API has been corrected.
* en/fill-directory-fixes-more:
dir: point treat_leading_path() warning to the right place
dir: restructure in a way to avoid passing around a struct dirent
dir: treat_leading_path() and read_directory_recursive(), round 2
clean: demonstrate a bug with pathspecs
Clarify documentation on committer/author identities.
* bc/author-committer-doc:
doc: provide guidance on user.name format
docs: expand on possible and recommended user config options
doc: move author and committer information to git-commit(1)
Work around test breakages caused by custom regex engine used in
libasan, when address sanitizer is used with more recent versions
of gcc and clang.
* jk/asan-build-fix:
Makefile: use compat regex with SANITIZE=address
The code recently added in this release to move to the entry beyond
the ones in the same directory in the index in the sparse-cone mode
did not count the number of entries to skip over incorrectly, which
has been corrected.
* ds/sparse-cone:
.mailmap: fix GGG authoship screwup
unpack-trees: correctly compute result count
"git restore --staged" did not correctly update the cache-tree
structure, resulting in bogus trees to be written afterwards, which
has been corrected.
* nd/switch-and-restore:
restore: invalidate cache-tree when removing entries with --staged
Reduce unnecessary round-trip when running "ls-remote" over the
stateless RPC mechanism.
* jk/no-flush-upon-disconnecting-slrpc-transport:
transport: don't flush when disconnecting stateless-rpc helper
