Jeff King [Fri, 10 Apr 2020 19:46:07 +0000 (15:46 -0400)]
git_config_parse_key(): return baselen as size_t
As with the recent change to parse_config_key(), the best type to return
a string length is a size_t, as it won't cause integer truncation for a
gigantic key. And as with that change, this is mostly a clarity /
hygiene issue for now, as our config parser would choke on such a large
key anyway.
There are a few ripple effects within the config code, as callers switch
to using size_t. I also adjusted a few related variables that iterate
over strings. The most unexpected change is that a call to strbuf_addf()
had to switch to strbuf_add(). We can't use a size_t with "%.*s",
because printf precisions must have type "int" (we could cast, of
course, but that would miss the point of using size_t in the first
place).
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Jeff King [Fri, 10 Apr 2020 19:44:45 +0000 (15:44 -0400)]
config: drop useless length variable in write_pair()
We compute the length of a subset of a string, but then use that length
only to feed a "%.*s" printf placeholder for the same string. We can
just use "%s" to achieve the same thing.
The variable became useless in cb891a5989 (Use a strbuf for building up
section header and key/value pair strings., 2007-12-14), which swapped
out a write() which _did_ use the length for a strbuf_addf() call.
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Jeff King [Fri, 10 Apr 2020 19:44:28 +0000 (15:44 -0400)]
parse_config_key(): return subsection len as size_t
We return the length to a subset of a string using an "int *"
out-parameter. This is fine most of the time, as we'd expect config keys
to be relatively short, but it could behave oddly if we had a gigantic
config key. A more appropriate type is size_t.
Let's switch over, which lets our callers use size_t as appropriate
(they are bound by our type because they must pass the out-parameter as
a pointer). This is mostly just a cleanup to make it clear this code
handles long strings correctly. In practice, our config parser already
chokes on long key names (because of a similar int/size_t mixup!).
When doing an int/size_t conversion, we have to be careful that nobody
was trying to assign a negative value to the variable. I manually
confirmed that for each case here. They tend to just feed the result to
xmemdupz() or similar; in a few cases I adjusted the parameter types for
helper functions to make sure the size_t is preserved.
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Jeff King [Fri, 10 Apr 2020 19:43:41 +0000 (15:43 -0400)]
remote: drop auto-strlen behavior of make_branch() and make_rewrite()
The make_branch() and make_rewrite() functions can take a NUL-terminated
string or a ptr/len pair. They use a sentinel value of "0" for the len
to tell the difference between the two. However, when parsing config
like:
[branch ""]
merge = whatever
whose key flattens to:
branch..merge
we might actually have a zero-length branch name. This is obviously
nonsense, but the current code would consider it as a NUL-terminated
string and use the branch name ".merge".
We could use a better sentinel value here (like "-1"), but that gets in
the way of moving to size_t, which is a more appropriate type for a
ptr/len combo.
Let's instead just drop this feature and have the callers (of which
there are only two total) use strlen() themselves. This simplifies the
code, and lets us move to using size_t.
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
On certain network filesystems (currently encountered with Isilon, but
in theory more network storage solutions could be causing the same
issue), when the directory in question is missing,
`raceproof_create_file()` fails with an `ERROR_INVALID_PARAMETER`
instead of an `ERROR_PATH_NOT_FOUND`.
Since it is highly unlikely that we produce such an error by mistake
(the parameters we pass are fairly benign), we can be relatively certain
that the directory is missing in this instance. So let's just translate
that error automagically.
This fixes https://github.com/git-for-windows/git/issues/1345.
Signed-off-by: Nathan Sanders <spekbukkem@gmail.com> Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
ci: let GitHub Actions upload failed tests' directories
Arguably, CI builds' most important task is to not only identify
regressions, but to make it as easy as possible to investigate what went
wrong.
In that light, we will want to provide users with a way to inspect the
tests' output as well as the corresponding directories.
This commit adds build steps that are only executed when tests failed,
uploading the relevant information as build artifacts. These artifacts
can then be downloaded by interested parties to diagnose the failures
more efficiently.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Đoàn Trần Công Danh <congdanhqx@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
With this patch, test failures will be annotated with a helpful,
clickable message in GitHub Actions. For details, see
https://github.com/actions/toolkit/blob/master/docs/problem-matchers.md
Note: we need to set `TEST_SHELL_PATH` to Bash so that the problem
matcher is fed a file and line number for each test failure.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Đoàn Trần Công Danh <congdanhqx@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
tests: when run in Bash, annotate test failures with file name/line number
When a test fails, it is nice to see where the corresponding code lives
in the worktree. Sadly, it seems that only Bash allows us to infer this
information. Let's do it when we detect that we're running in a Bash.
This will come in handy in the next commit, where we teach the GitHub
Actions workflow to annotate failed test runs with this information.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Đoàn Trần Công Danh <congdanhqx@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
We have GitHub Actions now. Running the same builds and tests in Azure
Pipelines would be redundant, and a waste of energy.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Đoàn Trần Công Danh <congdanhqx@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
README: add a build badge for the GitHub Actions runs
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Đoàn Trần Công Danh <congdanhqx@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
This patch adds CI builds via GitHub Actions. While the underlying
technology is at least _very_ similar to that of Azure Pipelines, GitHub
Actions are much easier to set up than Azure Pipelines:
- no need to install a GitHub App,
- no need to set up an Azure DevOps account,
- all you need to do is push to your fork on GitHub.
Therefore, it makes a lot of sense for us to have a working GitHub
Actions setup.
While copy/editing `azure-pipelines.yml` into
`.github/workflows/main.yml`, we also use the opportunity to accelerate
the step that sets up a minimal subset of Git for Windows' SDK in the
Windows-build job:
- we now download a `.tar.xz` stored in Azure Blobs and extract it
simultaneously by calling `curl` and piping the result to `tar`,
- decompressing via `xz`,
- all three utilities are installed together with Git for Windows
At the same time, we also make use of the matrix build feature, which
reduces the amount of repeated text by quite a bit.
Also, we do away with the parts that try to mount a file share on which
`prove` can store data between runs. It is just too complicated to set
up, and most times the tree changes anyway, so there is little return on
investment there.
Initial-patch-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Đoàn Trần Công Danh <congdanhqx@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
In a later patch, we will run Documentation job in GitHub Actions.
The job will run without elevated permission.
Run `gem` with `sudo` to elevate permission in order to be able to
install to system location.
This will also keep this installation in-line with other installation in
our Linux system for CI.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
[Danh: reword commit message] Signed-off-by: Đoàn Trần Công Danh <congdanhqx@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Explicitly install all of our build dependencies on Linux.
Since GitHub Action's Linux VM hasn't installed our build dependencies.
And there're no harm to reinstall them (in Travis)
Signed-off-by: Đoàn Trần Công Danh <congdanhqx@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
마누엘 [Fri, 10 Apr 2020 11:27:51 +0000 (11:27 +0000)]
interactive: explicitly `fflush` stdout before expecting input
At least one interactive command writes a prompt to `stdout` and then
reads user input on `stdin`: `git clean --interactive`. If the prompt is
left in the buffer, the user will not realize the program is waiting for
their input.
So let's just flush `stdout` before reading the user's input.
Signed-off-by: 마누엘 <nalla@hamal.uberspace.de> Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
interactive: refactor code asking the user for interactive input
There are quite a few code locations (e.g. `git clean --interactive`)
where Git asks the user for an answer. In preparation for fixing a bug
shared by all of them, and also to DRY up the code, let's refactor it.
Please note that most of these callers trimmed white-space both at the
beginning and at the end of the answer, instead of trimming only the
end (as the caller in `add-patch.c` does).
Therefore, technically speaking, we change behavior in this patch. At
the same time, it can be argued that this is actually a bug fix.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
mingw: help debugging by optionally executing bash with strace
MSYS2's strace facility is very useful for debugging... With this patch,
the bash will be executed through strace if the environment variable
GIT_STRACE_COMMANDS is set, which comes in real handy when investigating
issues in the test suite.
Also support passing a path to a log file via GIT_STRACE_COMMANDS to
force Git to call strace.exe with the `-o <path>` argument, i.e. to log
into a file rather than print the log directly.
That comes in handy when the output would otherwise misinterpreted by a
calling process as part of Git's output.
Note: the values "1", "yes" or "true" are *not* specifying paths, but
tell Git to let strace.exe log directly to the console.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
The default file history simplification of "git log -- <path>" or
"git rev-list -- <path>" focuses on providing the smallest set of
commits that first contributed a change. The revision walk greatly
restricts the set of walked commits by visiting only the first
TREESAME parent of a merge commit, when one exists. This means
that portions of the commit-graph are not walked, which can be a
performance benefit, but can also "hide" commits that added changes
but were ignored by a merge resolution.
The --full-history option modifies this by walking all commits and
reporting a merge commit as "interesting" if it has _any_ parent
that is not TREESAME. This tends to be an over-representation of
important commits, especially in an environment where most merge
commits are created by pull request completion.
Suppose we have a commit A and we create a commit B on top that
changes our file. When we merge the pull request, we create a merge
commit M. If no one else changed the file in the first-parent
history between M and A, then M will not be TREESAME to its first
parent, but will be TREESAME to B. Thus, the simplified history
will be "B". However, M will appear in the --full-history mode.
However, suppose that a number of topics T1, T2, ..., Tn were
created based on commits C1, C2, ..., Cn between A and M as
follows:
If the commits T1, T2, ... Tn did not change the file, then all of
P1 through Pn will be TREESAME to their first parent, but not
TREESAME to their second. This means that all of those merge commits
appear in the --full-history view, with edges that immediately
collapse into the lower history without introducing interesting
single-parent commits.
The --simplify-merges option was introduced to remove these extra
merge commits. By noticing that the rewritten parents are reachable
from their first parents, those edges can be simplified away. Finally,
the commits now look like single-parent commits that are TREESAME to
their "only" parent. Thus, they are removed and this issue does not
cause issues anymore. However, this also ends up removing the commit
M from the history view! Even worse, the --simplify-merges option
requires walking the entire history before returning a single result.
Many Git users are using Git alongside a Git service that provides
code storage alongside a code review tool commonly called "Pull
Requests" or "Merge Requests" against a target branch. When these
requests are accepted and merged, they typically create a merge
commit whose first parent is the previous branch tip and the second
parent is the tip of the topic branch used for the request. This
presents a valuable order to the parents, but also makes that merge
commit slightly special. Users may want to see not only which
commits changed a file, but which pull requests merged those commits
into their branch. In the previous example, this would mean the
users want to see the merge commit "M" in addition to the single-
parent commit "C".
Users are even more likely to want these merge commits when they
use pull requests to merge into a feature branch before merging that
feature branch into their trunk.
In some sense, users are asking for the "first" merge commit to
bring in the change to their branch. As long as the parent order is
consistent, this can be handled with the following rule:
Include a merge commit if it is not TREESAME to its first
parent, but is TREESAME to a later parent.
These merges look like the merge commits that would result from
running "git pull <topic>" on a main branch. Thus, the option to
show these commits is called "--show-pulls". This has the added
benefit of showing the commits created by closing a pull request or
merge request on any of the Git hosting and code review platforms.
To test these options, extend the standard test example to include
a merge commit that is not TREESAME to its first parent. It is
surprising that that option was not already in the example, as it
is instructive.
In particular, this extension demonstrates a common issue with file
history simplification. When a user resolves a merge conflict using
"-Xours" or otherwise ignoring one side of the conflict, they create
a TREESAME edge that probably should not be TREESAME. This leads
users to become frustrated and complain that "my change disappeared!"
In my experience, showing them history with --full-history and
--simplify-merges quickly reveals the problematic merge. As mentioned,
this option is expensive to compute. The --show-pulls option
_might_ show the merge commit (usually titled "resolving conflicts")
more quickly. Of course, this depends on the user having the correct
parent order, which is backwards when using "git pull master" from a
topic branch.
There are some special considerations when combining the --show-pulls
option with --simplify-merges. This requires adding a new PULL_MERGE
object flag to store the information from the initial TREESAME
comparisons. This helps avoid dropping those commits in later filters.
This is covered by a test, including how the parents can be simplified.
Since "struct object" has already ruined its 32-bit alignment by using
33 bits across parsed, type, and flags member, let's not make it worse.
PULL_MERGE is used in revision.c with the same value (1u<<15) as
REACHABLE in commit-graph.c. The REACHABLE flag is only used when
writing a commit-graph file, and a revision walk using --show-pulls
does not happen in the same process. Care must be taken in the future
to ensure this remains the case.
Update Documentation/rev-list-options.txt with significant details
around this option. This requires updating the example in the
History Simplification section to demonstrate some of the problems
with TREESAME second parents.
Signed-off-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Denton Liu [Tue, 7 Apr 2020 14:28:09 +0000 (10:28 -0400)]
pull: pass --autostash to merge
Before, `--autostash` only worked with `git pull --rebase`. However, in
the last patch, merge learned `--autostash` as well so there's no reason
why we should have this restriction anymore. Teach pull to pass
`--autostash` to merge, just like it did for rebase.
Signed-off-by: Denton Liu <liu.denton@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Denton Liu [Tue, 7 Apr 2020 14:28:08 +0000 (10:28 -0400)]
t5520: make test_pull_autostash() accept expect_parent_num
Before, test_pull_autostash() was hardcoded to run
`test_cmp_rev HEAD^ copy` to test that a rebase happened. However, in a
future patch, we plan on testing merging as well. Make
test_pull_autostash() accept a parent number as an argument so that, in
the future, we can test if a merge happened in addition to a rebase.
Signed-off-by: Denton Liu <liu.denton@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Denton Liu [Tue, 7 Apr 2020 14:28:07 +0000 (10:28 -0400)]
merge: teach --autostash option
In rebase, one can pass the `--autostash` option to cause the worktree
to be automatically stashed before continuing with the rebase. This
option is missing in merge, however.
Implement the `--autostash` option and corresponding `merge.autoStash`
option in merge which stashes before merging and then pops after.
This option is useful when a developer has some local changes on a topic
branch but they realize that their work depends on another branch.
Previously, they had to run something like
When an autostash is generated, it is automatically reapplied to the
worktree only in three explicit situations:
1. An incomplete merge is commit using `git commit`.
2. A merge completes successfully.
3. A merge is aborted using `git merge --abort`.
In all other situations where the merge state is removed using
remove_merge_branch_state() such as aborting a merge via
`git reset --hard`, the autostash is saved into the stash reflog
instead keeping the worktree clean.
Helped-by: Phillip Wood <phillip.wood@dunelm.org.uk> Suggested-by: Alban Gruin <alban.gruin@gmail.com> Signed-off-by: Denton Liu <liu.denton@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Denton Liu [Tue, 7 Apr 2020 14:28:06 +0000 (10:28 -0400)]
sequencer: implement apply_autostash_oid()
Split apply_save_autostash() into apply_autostash_oid() and
apply_save_autostash() where the former operates on an OID string and
the latter reads the OID from a file before passing it into
apply_save_autostash_oid().
This function is required for a future commmit which will rely on being
able to apply an autostash whose OID is stored as a string.
Signed-off-by: Denton Liu <liu.denton@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Denton Liu [Tue, 7 Apr 2020 14:28:05 +0000 (10:28 -0400)]
sequencer: implement save_autostash()
Extract common functionality of apply_autostash() into
apply_save_autostash() and use it to implement save_autostash(). This
function will be used in a future commit.
The difference between save_autostash() and apply_autostash() is that
the former does not try to apply the stash. It skips that step and
just stores the created entry in the stash reflog.
This is useful in the case where we abort an operation when an autostash
is present but we don't want to dirty the worktree with the application
of the stash. For example, in a future commit, we will implement
`git merge --autostash`. Since merges can be aborted using
`git reset --hard`, we'd make use of save_autostash() to save the
autostash entry instead of applying it to the worktree thus keeping the
worktree undirtied.
Signed-off-by: Denton Liu <liu.denton@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Denton Liu [Tue, 7 Apr 2020 14:28:04 +0000 (10:28 -0400)]
sequencer: unlink autostash in apply_autostash()
Explicitly remove autostash file in apply_autostash() once it has been
applied successfully.
This is currently a no-op because the only users of this function will unlink
the state (including the autostash file) after this function runs.
However, in the future, we will introduce a user of the function that
does not explicitly remove the state so we do it here.
Signed-off-by: Denton Liu <liu.denton@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Denton Liu [Tue, 7 Apr 2020 14:28:03 +0000 (10:28 -0400)]
sequencer: extract perform_autostash() from rebase
Lib-ify the autostash code by extracting perform_autostash() from rebase
into sequencer. In a future commit, this will be used to implement
`--autostash` in other builtins.
This patch is best viewed with `--color-moved`.
Signed-off-by: Denton Liu <liu.denton@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Denton Liu [Tue, 7 Apr 2020 14:28:02 +0000 (10:28 -0400)]
rebase: generify create_autostash()
In the future, we plan on lib-ifying create_autostash() so we need it to
be more generic. Make it more generic by making it accept a
`struct repository` argument instead of implicitly using the non-repo
functions and `the_repository`. Also, make it accept a `path` argument
so that we no longer rely have to rely on `struct rebase_options`.
Finally, make it accept a `default_reflog_action` argument so we no
longer have to rely on `DEFAULT_REFLOG_ACTION`.
Signed-off-by: Denton Liu <liu.denton@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Denton Liu [Tue, 7 Apr 2020 14:28:01 +0000 (10:28 -0400)]
rebase: extract create_autostash()
In a future commit, we will lib-ify this code. In preparation for
this, extract the code into the create_autostash() function so that it
can be cleaned up before it is finally lib-ified.
This patch is best viewed with `--color-moved` and
`--color-moved-ws=allow-indentation-change`.
Signed-off-by: Denton Liu <liu.denton@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Denton Liu [Tue, 7 Apr 2020 14:27:59 +0000 (10:27 -0400)]
rebase: generify reset_head()
In the future, we plan on lib-ifying reset_head() so we need it to
be more generic. Make it more generic by making it accept a
`struct repository` argument instead of implicitly using the non-repo
functions. Also, make it accept a `const char *default_reflog_action`
argument so that the default action of "rebase" isn't hardcoded in.
Signed-off-by: Denton Liu <liu.denton@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Denton Liu [Tue, 7 Apr 2020 14:27:58 +0000 (10:27 -0400)]
rebase: use apply_autostash() from sequencer.c
The apply_autostash() function in builtin/rebase.c is similar enough to
the apply_autostash() function in sequencer.c that they are almost
interchangeable, except for the type of arg they accept. Make the
sequencer.c version extern and use it in rebase.
The rebase version was introduced in 6defce2b02 (builtin rebase: support
`--autostash` option, 2018-09-04) as part of the shell to C conversion.
It opted to duplicate the function because, at the time, there was
another in-progress project converting interactive rebase from shell to
C as well and they did not want to clash with them by refactoring
sequencer.c version of apply_autostash(). Since both efforts are long
done, we can freely combine them together now.
Signed-off-by: Denton Liu <liu.denton@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Denton Liu [Tue, 7 Apr 2020 14:27:56 +0000 (10:27 -0400)]
sequencer: make apply_autostash() accept a path
In order to make apply_autostash() more generic for future extraction, make
it accept a `path` argument so that the location from where to read the
reference to the autostash commit can be customized. Remove the `opts`
argument since it was unused before anyway.
Signed-off-by: Denton Liu <liu.denton@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Denton Liu [Tue, 7 Apr 2020 14:27:55 +0000 (10:27 -0400)]
rebase: use read_oneliner()
Since in sequencer.c, read_one() basically duplicates the functionality
of read_oneliner(), reduce code duplication by replacing read_one() with
read_oneliner().
This was done with the following Coccinelle script
@@
expression a, b;
@@
- read_one(a, b)
+ !read_oneliner(b, a, READ_ONELINER_WARN_MISSING)
and long lines were manually broken up.
Signed-off-by: Denton Liu <liu.denton@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Jeff King [Fri, 10 Apr 2020 03:04:11 +0000 (23:04 -0400)]
repository: mark the "refs" pointer as private
The "refs" pointer in a struct repository starts life as NULL, but then
is lazily initialized when it is accessed via get_main_ref_store().
However, it's easy for calling code to forget this and access it
directly, leading to code which works _some_ of the time, but fails if
it is called before anybody else accesses the refs.
This was the cause of the bug fixed by 5ff4b920eb (sha1-name: do not
assume that the ref store is initialized, 2020-04-09). In order to
prevent similar bugs, let's more clearly mark the "refs" field as
private.
In addition to helping future code, the name change will help us audit
any existing direct uses. Besides get_main_ref_store() itself, it turns
out there is only one. But we know it's OK as it is on the line directly
after the fix from 5ff4b920eb, which will have initialized the pointer.
However it's still a good idea for it to model the proper use of the
accessing function, so we'll convert it.
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
builtin/receive-pack: use constant-time comparison for HMAC value
When we're comparing a push cert nonce, we currently do so using strcmp.
Most implementations of strcmp short-circuit and exit as soon as they
know whether two values are equal. This, however, is a problem when
we're comparing the output of HMAC, as it leaks information in the time
taken about how much of the two values match if they do indeed differ.
In our case, the nonce is used to prevent replay attacks against our
server via the embedded timestamp and replay attacks using requests from
a different server via the HMAC. Push certs, which contain the nonces,
are signed, so an attacker cannot tamper with the nonces without
breaking validation of the signature. They can, of course, create their
own signatures with invalid nonces, but they can also create their own
signatures with valid nonces, so there's nothing to be gained. Thus,
there is no security problem.
Even though it doesn't appear that there are any negative consequences
from the current technique, for safety and to encourage good practices,
let's use a constant time comparison function for nonce verification.
POSIX does not provide one, but they are easy to write.
The technique we use here is also used in NaCl and the Go standard
library and relies on the fact that bitwise or and xor are constant time
on all known architectures.
We need not be concerned about exiting early if the actual and expected
lengths differ, since the standard cryptographic assumption is that
everyone, including an attacker, knows the format of and algorithm used
in our nonces (and in any event, they have the source code and can
determine it easily). As a result, we assume everyone knows how long
our nonces should be. This philosophy is also taken by the Go standard
library and other cryptographic libraries when performing constant time
comparisons on HMAC values.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Junio C Hamano [Fri, 10 Apr 2020 00:03:45 +0000 (17:03 -0700)]
sha1-name: do not assume that the ref store is initialized
c931ba4e (sha1-name.c: remove the_repo from handle_one_ref(),
2019-04-16) replaced the use of for_each_ref() helper, which works
with the main ref store of the default repository instance, with
refs_for_each_ref(), which can work on any ref store instance, by
assuming that the repository instance the function is given has its
ref store already initialized.
But it is possible that nobody has initialized it, in which case,
the code ends up dereferencing a NULL pointer.
Reported-by: Érico Rolim <erico.erc@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
bloom: ignore renames when computing changed paths
The changed-path Bloom filters record an entry in the filter for
every path that was changed. This includes every add and delete,
regardless of whether a rename was detected. Detecting renames
causes significant performance issues, but also will trigger
downloading missing blobs in partial clone.
The simple fix is to disable rename detection when computing a
changed-path Bloom filter. This should already be disabled by
default, but it is good to explicitly enforce the intended
behavior.
Signed-off-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Martin Ågren [Thu, 9 Apr 2020 10:35:41 +0000 (12:35 +0200)]
config.txt: move closing "----" to cover entire listing
Commit 1925fe0c8a ("Documentation: wrap config listings in "----"",
2019-09-07) wrapped this fairly large block of example config directives
in "----". The closing "----" ended up a few lines too early though.
Make sure to include the trailing "IncludeIf.onbranch:..." example, too.
Signed-off-by: Martin Ågren <martin.agren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
When trying to stash part of the worktree changes by splitting a hunk
and then only partially accepting the split bits and pieces, the user
is presented with a rather cryptic error:
error: patch failed: <file>:<line>
error: test: patch does not apply
Cannot remove worktree changes
and the command would fail to stash the desired parts of the worktree
changes (even if the `stash` ref was actually updated correctly).
We even have a test case demonstrating that failure, carrying it for
four years already.
The explanation: when splitting a hunk, the changed lines are no longer
separated by more than 3 lines (which is the amount of context lines
Git's diffs use by default), but less than that. So when staging only
part of the diff hunk for stashing, the resulting diff that we want to
apply to the worktree in reverse will contain those changes to be
dropped surrounded by three context lines, but since the diff is
relative to HEAD rather than to the worktree, these context lines will
not match.
Example time. Let's assume that the file README contains these lines:
We
the
people
and the worktree added some lines so that it contains these lines
instead:
We
are
the
kind
people
and the user tries to stash the line containing "are", then the command
will internally stage this line to a temporary index file and try to
revert the diff between HEAD and that index file. The diff hunk that
`git stash` tries to revert will look somewhat like this:
@@ -1776,3 +1776,4
We
+are
the
people
It is obvious, now, that the trailing context lines overlap with the
part of the original diff hunk that the user did *not* want to stash.
Keeping in mind that context lines in diffs serve the primary purpose of
finding the exact location when the diff does not apply precisely (but
when the exact line number in the file to be patched differs from the
line number indicated in the diff), we work around this by reducing the
amount of context lines: the diff was just generated.
Note: this is not a *full* fix for the issue. Just as demonstrated in
t3701's 'add -p works with pathological context lines' test case, there
are ambiguities in the diff format. It is very rare in practice, of
course, to encounter such repeated lines.
The full solution for such cases would be to replace the approach of
generating a diff from the stash and then applying it in reverse by
emulating `git revert` (i.e. doing a 3-way merge). However, in `git
stash -p` it would not apply to `HEAD` but instead to the worktree,
which makes this non-trivial to implement as long as we also maintain a
scripted version of `add -i`.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
In 7e9e048661 (stash -p: demonstrate failure of split with mixed y/n,
2015-04-16), a regression test for a known breakage that was added to
the test script `t3904-stash-patch.sh` that demonstrated that splitting
a hunk and trying to stash only part of that split hunk fails (but
shouldn't).
As expected, it still fails, but for the wrong reason: once the bug is
fixed, we would expect stderr to show nothing, yet the regression test
expects stderr to show something.
Let's fix that by telling that regression test case to expect nothing to
be printed to stderr.
While at it, also drop the obvious left-over from debugging where the
regression test did not mind `git stash -p` to return a non-zero exit
status.
Of course, the regression test still fails, but this time for the
correct reason.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
mingw: do not treat `COM0` as a reserved file name
In 4dc42c6c186 (mingw: refuse paths containing reserved names,
2019-12-21), we started disallowing file names that are reserved, e.g.
`NUL`, `CONOUT$`, etc.
This included `COM<n>` where `<n>` is a digit. Unfortunately, this
includes `COM0` but only `COM1`, ..., `COM9` are reserved, according to
the official documentation, `COM0` is mentioned in the "NT Namespaces"
section but it is explicitly _omitted_ from the list of reserved names:
https://docs.microsoft.com/en-us/windows/win32/fileio/naming-a-file#naming-conventions
Tests corroborate this: it is totally possible to write a file called
`com0.c` on Windows 10, but not `com1.c`.
So let's tighten the code to disallow only the reserved `COM<n>` file
names, but to allow `COM0` again.
This fixes https://github.com/git-for-windows/git/issues/2470.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
mingw: use modern strftime implementation if possible
Microsoft introduced a new "Universal C Runtime Library" (UCRT) with
Visual Studio 2015. The UCRT comes with a new strftime() implementation
that supports more date formats. We link git against the older
"Microsoft Visual C Runtime Library" (MSVCRT), so to use the UCRT
strftime() we need to load it from ucrtbase.dll using
DECLARE_PROC_ADDR()/INIT_PROC_ADDR().
Most supported Windows systems should have recieved the UCRT via Windows
update, but in some cases only MSVCRT might be available. In that case
we fall back to using that implementation.
With this change, it is possible to use e.g. the `%g` and `%V` date
format specifiers, e.g.
git show -s --format=%cd --date=format:‘%g.%V’ HEAD
Without this change, the user would see this error message on Windows:
fatal: invalid strftime format: '‘%g.%V’'
This fixes https://github.com/git-for-windows/git/issues/2495
Signed-off-by: Matthias Aßhauer <mha1993@live.de> Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Emma Brooks [Wed, 8 Apr 2020 04:31:38 +0000 (04:31 +0000)]
format-patch: teach --no-encode-email-headers
When commit subjects or authors have non-ASCII characters, git
format-patch Q-encodes them so they can be safely sent over email.
However, if the patch transfer method is something other than email (web
review tools, sneakernet), this only serves to make the patch metadata
harder to read without first applying it (unless you can decode RFC 2047
in your head). git am as well as some email software supports
non-Q-encoded mail as described in RFC 6531.
Add --[no-]encode-email-headers and format.encodeEmailHeaders to let the
user control this behavior.
Signed-off-by: Emma Brooks <me@pluvano.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
In 6cdccfce1e0f (i18n: make GETTEXT_POISON a runtime option,
2018-11-08), the `jobname` was adjusted to have the `GIT_TEST_` prefix,
but that prefix makes no sense in this context.
Co-authored-by: Đoàn Trần Công Danh <congdanhqx@gmail.com> Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Đoàn Trần Công Danh <congdanhqx@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
For each CI system we support, we need a specific arm in that if/else
construct in ci/lib.sh. Let's add one for GitHub Actions.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Đoàn Trần Công Danh <congdanhqx@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
ci/lib: if CI type is unknown, show the environment variables
This should help with adding new CI-specific if-else arms.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Đoàn Trần Công Danh <congdanhqx@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Junio C Hamano [Wed, 8 Apr 2020 05:16:30 +0000 (22:16 -0700)]
Merge branch 'dd/ci-musl-libc' into HEAD
* dd/ci-musl-libc:
travis: build and test on Linux with musl libc and busybox
ci/linux32: libify install-dependencies step
ci: refactor docker runner script
ci/linux32: parameterise command to switch arch
ci/lib-docker: preserve required environment variables
ci: make MAKEFLAGS available inside the Docker container in the Linux32 job
Junio C Hamano [Wed, 8 Apr 2020 05:16:21 +0000 (22:16 -0700)]
Merge branch 'dd/test-with-busybox' into HEAD
* dd/test-with-busybox:
t5703: feed raw data into test-tool unpack-sideband
t4124: tweak test so that non-compliant diff(1) can also be used
t7063: drop non-POSIX argument "-ls" from find(1)
t5616: use rev-parse instead to get HEAD's object_id
t5003: skip conversion test if unzip -a is unavailable
t5003: drop the subshell in test_lazy_prereq
test-lib-functions: test_cmp: eval $GIT_TEST_CMP
t4061: use POSIX compliant regex(7)
Denton Liu [Tue, 7 Apr 2020 14:27:54 +0000 (10:27 -0400)]
sequencer: make read_oneliner() extern
The function read_oneliner() is a generally useful util function.
Instead of hiding it as a static function within sequencer.c, extern it
so that it can be reused by others.
This patch is best viewed with --color-moved.
Signed-off-by: Denton Liu <liu.denton@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Denton Liu [Tue, 7 Apr 2020 14:27:53 +0000 (10:27 -0400)]
sequencer: configurably warn on non-existent files
In the future, we plan on externing read_oneliner(). Future users of
read_oneliner() will want the ability to output warnings in the event
that the `path` doesn't exist. Introduce the
`READ_ONELINER_WARN_MISSING` flag which, if active, would issue a
warning when a file doesn't exist by always executing warning_errno()
in the case where strbuf_read_file() fails.
Signed-off-by: Denton Liu <liu.denton@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Denton Liu [Tue, 7 Apr 2020 14:27:52 +0000 (10:27 -0400)]
sequencer: make read_oneliner() accept flags
In a future commit, we will need read_oneliner() to accept flags other
than just `skip_if_empty`. Instead of having an argument for each flag,
teach read_oneliner() to accept the bitfield `flags` instead. For now,
only recognize the `READ_ONELINER_SKIP_IF_EMPTY` flag. More flags will
be added in a future commit.
The result of this is that parallel topics which introduce invocations
of read_oneliner() will still be compatible with this new function
signature since, instead of passing 1 or 0 for `skip_if_empty`, they'll
be passing 1 or 0 to `flags`, which gives equivalent behavior.
Mechanically fix up invocations of read_oneliner() with the following
spatch
Denton Liu [Tue, 7 Apr 2020 14:27:51 +0000 (10:27 -0400)]
sequencer: make file exists check more efficient
We currently check whether a file exists and return early before reading
the file. Instead of accessing the file twice, always read the file and
check `errno` to see if the file doesn't exist.
Signed-off-by: Denton Liu <liu.denton@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Jonathan Tan [Tue, 7 Apr 2020 22:11:43 +0000 (15:11 -0700)]
diff: restrict when prefetching occurs
Commit 7fbbcb21b1 ("diff: batch fetching of missing blobs", 2019-04-08)
optimized "diff" by prefetching blobs in a partial clone, but there are
some cases wherein blobs do not need to be prefetched. In these cases,
any command that uses the diff machinery will unnecessarily fetch blobs.
diffcore_std() may read blobs when it calls the following functions:
(1) diffcore_skip_stat_unmatch() (controlled by the config variable
diff.autorefreshindex)
(2) diffcore_break() and diffcore_merge_broken() (for break-rewrite
detection)
(3) diffcore_rename() (for rename detection)
(4) diffcore_pickaxe() (for detecting addition/deletion of specified
string)
Instead of always prefetching blobs, teach diffcore_skip_stat_unmatch(),
diffcore_break(), and diffcore_rename() to prefetch blobs upon the first
read of a missing object. This covers (1), (2), and (3): to cover the
rest, teach diffcore_std() to prefetch if the output type is one that
includes blob data (and hence blob data will be required later anyway),
or if it knows that (4) will be run.
Helped-by: Jeff King <peff@peff.net> Signed-off-by: Jonathan Tan <jonathantanmy@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Jonathan Tan [Tue, 7 Apr 2020 22:11:42 +0000 (15:11 -0700)]
diff: refactor object read
Refactor the object reads in diff_populate_filespec() to have the first
object read not be in an if/else branch, because in a future patch, a
retry will be added to that first object read.
Signed-off-by: Jonathan Tan <jonathantanmy@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Jonathan Tan [Tue, 7 Apr 2020 22:11:41 +0000 (15:11 -0700)]
diff: make diff_populate_filespec_options struct
The behavior of diff_populate_filespec() currently can be customized
through a bitflag, but a subsequent patch requires it to support a
non-boolean option. Replace the bitflag with an options struct.
Signed-off-by: Jonathan Tan <jonathantanmy@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
There is a lot of code to honor GIT_REFLOG_ACTION throughout git,
including some in sequencer.c; unfortunately, reflog_message() and its
callers ignored it. Instruct reflog_message() to check the existing
environment variable, and use it when present as an override to
action_name().
Also restructure pick_commits() to only temporarily modify
GIT_REFLOG_ACTION for a short duration and then restore the old value,
so that when we do this setting within a loop we do not keep adding "
(pick)" substrings and end up with a reflog message of the form
rebase (pick) (pick) (pick) (finish): returning to refs/heads/master
Signed-off-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
In a later patch, we will add new Travis Job for linux-musl.
Most of other code in this file could be reuse for that job.
Move the code to install dependencies to a common script.
Should we add new CI system that can run directly in container,
we can reuse this script for installation step.
Signed-off-by: Đoàn Trần Công Danh <congdanhqx@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
We will support alpine check in docker later in this series.
While we're at it, tell people to run as root in podman,
if podman is used as drop-in replacement for docker,
because podman will map host-user to container's root,
therefore, mapping their permission.
Signed-off-by: Đoàn Trần Công Danh <congdanhqx@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
We're using "su -m" to preserve environment variables in the shell run
by "su". But, that options will be ignored while "-l" (aka "--login") is
specified in util-linux and busybox's su.
In a later patch this script will be reused for checking Git for Linux
with musl libc on Alpine Linux, Alpine Linux uses "su" from busybox.
Since we don't have interest in all environment variables,
pass only those necessary variables to the inner script.
Signed-off-by: Đoàn Trần Công Danh <congdanhqx@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Damien Robert [Mon, 6 Apr 2020 13:57:09 +0000 (15:57 +0200)]
doc: --recurse-submodules mostly applies to active submodules
The documentation refers to "initialized" or "populated" submodules,
to explain which submodules are affected by '--recurse-submodules', but
the real terminology here is 'active' submodules. Update the
documentation accordingly.
Some terminology:
- Active is defined in gitsubmodules(7), it only involves the
configuration variables 'submodule.active', 'submodule.<name>.active'
and 'submodule.<name>.url'. The function
submodule.c::is_submodule_active checks that a submodule is active.
- Populated means that the submodule's working tree is present (and the
gitfile correctly points to the submodule repository), i.e. either the
superproject was cloned with ` --recurse-submodules`, or the user ran
`git submodule update --init`, or `git submodule init [<path>]` and
`git submodule update [<path>]` separately which populated the
submodule working tree. This does not involve the 3 configuration
variables above.
- Initialized (at least in the context of the man pages involved in this
patch) means both "populated" and "active" as defined above, i.e. what
`git submodule update --init` does.
The --recurse-submodules option mostly affects active submodules. An
exception is `git fetch` where the option affects populated submodules.
As a consequence, in `git pull --recurse-submodules` the fetch affects
populated submodules, but the resulting working tree update only affects
active submodules.
In the documentation of `git-pull`, let's distinguish between the
fetching part which affects populated submodules, and the updating of
worktrees, which only affects active submodules.
Signed-off-by: Damien Robert <damien.olivier.robert+git@gmail.com> Helped-by: Philippe Blain <levraiphilippeblain@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Damien Robert [Mon, 6 Apr 2020 13:57:08 +0000 (15:57 +0200)]
doc: be more precise on (fetch|push).recurseSubmodules
The default value also depends on the value of submodule.recurse.
Use this opportunity to correct some grammar mistakes in
Documentation/config/fetch.txt signaled by Robert P. J. Day.
Also mention `fetch.recurseSubmodules` in fetch-options.txt. In
git-push.txt, `push.recurseSubmodules` is implicitly mentioned (by
explaining how to disable it), so no need to add it there.
Lastly add a link to `git-fetch` in `git-pull.txt` to explain the
meaning of `--recurse-submodules` there.
Signed-off-by: Damien Robert <damien.olivier.robert+git@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Jeff King [Mon, 6 Apr 2020 19:49:40 +0000 (15:49 -0400)]
fast-import: replace custom hash with hashmap.c
We use a custom hash in fast-import to store the set of objects we've
imported so far. It has a fixed set of 2^16 buckets and chains any
collisions with a linked list. As the number of objects grows larger
than that, the load factor increases and we degrade to O(n) lookups and
O(n^2) insertions.
We can scale better by using our hashmap.c implementation, which will
resize the bucket count as we grow. This does incur an extra memory cost
of 8 bytes per object, as hashmap stores the integer hash value for each
entry in its hashmap_entry struct (which we really don't care about
here, because we're just reusing the embedded object hash). But I think
the numbers below justify this (and our per-object memory cost is
already much higher).
I also looked at using khash, but it seemed to perform slightly worse
than hashmap at all sizes, and worse even than the existing code for
small sizes. It's also awkward to use here, because we want to look up a
"struct object_entry" from a "struct object_id", and it doesn't handle
mismatched keys as well. Making a mapping of object_id to object_entry
would be more natural, but that would require pulling the embedded oid
out of the object_entry or incurring an extra 32 bytes per object.
In a synthetic test creating as many cheap, tiny objects as possible
which points to hashmap as the winner. We didn't have any perf tests for
fast-export or fast-import, so I added one as a more real-world case.
It uses an export without blobs since that's significantly cheaper than
a full one, but still is an interesting case people might use (e.g., for
rewriting history). It will emphasize this change in some ways (as a
percentage we spend more time making objects and less shuffling blob
bytes around) and less in others (the total object count is lower).
Here are the results for linux.git:
Test HEAD^ HEAD
----------------------------------------------------------------------------
9300.1: export (no-blobs) 67.64(66.96+0.67) 67.81(67.06+0.75) +0.3%
9300.2: import (no-blobs) 284.04(283.34+0.69) 198.09(196.01+0.92) -30.3%
It only has ~5.2M commits and trees, so this is a larger effect than I
expected (the 2^23 case above only improved by 50s or so, but here we
gained almost 90s). This is probably due to actually performing more
object lookups in a real import with trees and commits, as opposed to
just dumping a bunch of blobs into a pack.
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
commit-graph: add GIT_TEST_COMMIT_GRAPH_CHANGED_PATHS test flag
Add GIT_TEST_COMMIT_GRAPH_CHANGED_PATHS test flag to the test setup suite
in order to toggle writing Bloom filters when running any of the git tests.
If set to true, we will compute and write Bloom filters every time a test
calls `git commit-graph write`, as if the `--changed-paths` option was
passed in.
The test suite passes when GIT_TEST_COMMIT_GRAPH and
GIT_TEST_COMMIT_GRAPH_CHANGED_PATHS are enabled.
Helped-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Garima Singh <garima.singh@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
t4216: add end to end tests for git log with Bloom filters
These tests exercises writing commit graph with Bloom filters
and exercises 'git log -- path' with all the applicable
options. They check that the output is the same with and
without Bloom filters, confirm Bloom filters were used by
checking if trace2 statistics were logged correctly.
Also confirms cases where Bloom filters are not used:
1. Multiple path specs,
2. --walk-reflogs (see patch titled 'revision.c: use Bloom filters...'
for details,
3. If the latest commit graph does not have Bloom filters
Signed-off-by: Garima Singh <garima.singh@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
revision.c: add trace2 stats around Bloom filter usage
Add trace2 statistics around Bloom filter usage and behavior
for 'git log -- path' commands that are hoping to benefit from
the presence of computed changed paths Bloom filters.
These statistics are great for performance analysis work and
for formal testing, which we will see in the commit following
this one.
Helped-by: Derrick Stolee <dstolee@microsoft.com Helped-by: SZEDER Gábor <szeder.dev@gmail.com> Helped-by: Jonathan Tan <jonathantanmy@google.com> Signed-off-by: Garima Singh <garima.singh@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
revision.c: use Bloom filters to speed up path based revision walks
Revision walk will now use Bloom filters for commits to speed up
revision walks for a particular path (for computing history for
that path), if they are present in the commit-graph file.
We load the Bloom filters during the prepare_revision_walk step,
currently only when dealing with a single pathspec. Extending
it to work with multiple pathspecs can be explored and built on
top of this series in the future.
While comparing trees in rev_compare_trees(), if the Bloom filter
says that the file is not different between the two trees, we don't
need to compute the expensive diff. This is where we get our
performance gains. The other response of the Bloom filter is '`:maybe',
in which case we fall back to the full diff calculation to determine
if the path was changed in the commit.
We do not try to use Bloom filters when the '--walk-reflogs' option
is specified. The '--walk-reflogs' option does not walk the commit
ancestry chain like the rest of the options. Incorporating the
performance gains when walking reflog entries would add more
complexity, and can be explored in a later series.
Performance Gains:
We tested the performance of `git log -- <path>` on the git repo, the linux
and some internal large repos, with a variety of paths of varying depths.
On the git and linux repos:
- we observed a 2x to 5x speed up.
On a large internal repo with files seated 6-10 levels deep in the tree:
- we observed 10x to 20x speed ups, with some paths going up to 28 times
faster.
Helped-by: Derrick Stolee <dstolee@microsoft.com Helped-by: SZEDER Gábor <szeder.dev@gmail.com> Helped-by: Jonathan Tan <jonathantanmy@google.com> Signed-off-by: Garima Singh <garima.singh@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
commit-graph: add --changed-paths option to write subcommand
Add --changed-paths option to git commit-graph write. This option will
allow users to compute information about the paths that have changed
between a commit and its first parent, and write it into the commit graph
file. If the option is passed to the write subcommand we set the
COMMIT_GRAPH_WRITE_BLOOM_FILTERS flag and pass it down to the
commit-graph logic.
Helped-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Garima Singh <garima.singh@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
commit-graph: reuse existing Bloom filters during write
Add logic to
a) parse Bloom filter information from the commit graph file and,
b) re-use existing Bloom filters.
See Documentation/technical/commit-graph-format for the format in which
the Bloom filter information is written to the commit graph file.
To read Bloom filter for a given commit with lexicographic position
'i' we need to:
1. Read BIDX[i] which essentially gives us the starting index in BDAT for
filter of commit i+1. It is essentially the index past the end
of the filter of commit i. It is called end_index in the code.
2. For i>0, read BIDX[i-1] which will give us the starting index in BDAT
for filter of commit i. It is called the start_index in the code.
For the first commit, where i = 0, Bloom filter data starts at the
beginning, just past the header in the BDAT chunk. Hence, start_index
will be 0.
3. The length of the filter will be end_index - start_index, because
BIDX[i] gives the cumulative 8-byte words including the ith
commit's filter.
We toggle whether Bloom filters should be recomputed based on the
compute_if_not_present flag.
Helped-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Garima Singh <garima.singh@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
commit-graph: write Bloom filters to commit graph file
Update the technical documentation for commit-graph-format with
the formats for the Bloom filter index (BIDX) and Bloom filter
data (BDAT) chunks. Write the computed Bloom filters information
to the commit graph file using this format.
Helped-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Garima Singh <garima.singh@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Philippe Blain [Sun, 5 Apr 2020 15:50:19 +0000 (15:50 +0000)]
pull doc: correct outdated description of an example
Since f269048754 (fetch: opportunistically update tracking refs,
2013-05-11), the underlying `git fetch` in `git pull <remote> <branch>`
updates the configured remote-tracking branch for <branch>.
However, an example in the 'Examples' section of the `git pull`
documentation still states that this is not the case.
Correct the description of this example.
Signed-off-by: Philippe Blain <levraiphilippeblain@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Philippe Blain [Sun, 5 Apr 2020 15:50:18 +0000 (15:50 +0000)]
pull doc: refer to a specific section in 'fetch' doc
The documentation for the `<refspec>` parameter in the `git fetch`
documentation refers to the section "CONFIGURED REMOTE-TRACKING
BRANCHES" in this same documentation page.
In the `git pull` documentation, let's also refer specifically to this
section instead of just linking to the `git fetch` documentation.
Signed-off-by: Philippe Blain <levraiphilippeblain@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Jeff King [Sat, 4 Apr 2020 14:58:29 +0000 (10:58 -0400)]
Makefile: avoid running curl-config unnecessarily
Commit 94a88e2524 (Makefile: avoid running curl-config multiple times,
2020-03-26) put the call to $(CURL_CONFIG) into a "simple" variable
which is expanded immediately, rather than expanding it each time it's
needed. However, that also means that we expand it whenever the Makefile
is parsed, whether we need it or not.
This is wasteful, but also breaks the ci/test-documentation.sh job, as
it does not have curl at all and complains about the extra messages to
stderr. An easy way to see it is just:
$ make CURL_CONFIG=does-not-work check-builtins
make: does-not-work: Command not found
make: does-not-work: Command not found
GIT_VERSION = 2.26.0.108.gb3f3f45f29
make: does-not-work: Command not found
make: does-not-work: Command not found
./check-builtins.sh
We can get the best of both worlds if we're willing to accept a little
Makefile hackery. Courtesy of the article at:
this patch uses a lazily-evaluated recursive variable which replaces its
contents with an immediately assigned simple one on first use.
Reported-by: Johannes Schindelin <Johannes.Schindelin@gmx.de> Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
git-rebase.txt: add another hook to the hooks section, and explain more
For more discussion about these hooks, their history relative to rebase,
and logical consistency between different types of operations, see
https://lore.kernel.org/git/CABPp-BG0bFKUage5cN_2yr2DkmS04W2Z9Pg5WcROqHznV3XBdw@mail.gmail.com/
and the links to some threads referenced therein.
Signed-off-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Jonathan Tan [Thu, 2 Apr 2020 19:19:16 +0000 (12:19 -0700)]
promisor-remote: accept 0 as oid_nr in function
There are 3 callers to promisor_remote_get_direct() that first check if
the number of objects to be fetched is equal to 0. Fold that check into
promisor_remote_get_direct(), and in doing so, be explicit as to what
promisor_remote_get_direct() does if oid_nr is 0 (it returns 0, success,
immediately).
Signed-off-by: Jonathan Tan <jonathantanmy@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Li Xuejiang [Thu, 2 Apr 2020 08:42:51 +0000 (16:42 +0800)]
git-submodule.sh: setup uninitialized variables
We have an environment variable `jobs=16` defined in our CI system, and
this environment makes our build job failed with the following message:
error: pathspec '16' did not match any file(s) known to git
The pathspec '16' for Git command is from the environment variable
"jobs".
This is because "git-submodule" command is implemented in shell script,
and environment variables may change its behavior. Set values for
uninitialized variables, such as "jobs" and "recommend_shallow" will
fix this issue.
Helped-by: Jiang Xin <worldhello.net@gmail.com> Signed-off-by: Li Xuejiang <xuejiang@alibaba-inc.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
The git-update-ref(1) command can only handle queueing transactions
right now via its "--stdin" parameter, but there is no way for users to
handle the transaction itself in a more explicit way. E.g. in a
replicated scenario, one may imagine a coordinator that spawns
git-update-ref(1) for multiple repositories and only if all agree that
an update is possible will the coordinator send a commit. Such a
transactional session could look like
> start
< start: ok
> update refs/heads/master $OLD $NEW
> prepare
< prepare: ok
# All nodes have returned "ok"
> commit
< commit: ok
or
> start
< start: ok
> create refs/heads/master $OLD $NEW
> prepare
< fatal: cannot lock ref 'refs/heads/master': reference already exists
# On all other nodes:
> abort
< abort: ok
In order to allow for such transactional sessions, this commit
introduces four new commands for git-update-ref(1), which matches those
we have internally already with the exception of "start":
- start: start a new transaction
- prepare: prepare the transaction, that is try to lock all
references and verify their current value matches the
expected one
- commit: explicitly commit a session, that is update references to
match their new expected state
- abort: abort a session and roll back all changes
By design, git-update-ref(1) will commit as soon as standard input is
being closed. While fine in a non-transactional world, it is definitely
unexpected in a transactional world. Because of this, as soon as any of
the new transactional commands is used, the default will change to
aborting without an explicit "commit". To avoid a race between queueing
updates and the first "prepare" that starts a transaction, the "start"
command has been added to start an explicit transaction.
Add some tests to exercise this new functionality.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
The git-update-ref(1) supports a `--stdin` mode that allows it to read
all reference updates from standard input. This is mainly used to allow
for atomic reference updates that are all or nothing, so that either all
references will get updated or none.
Currently, git-update-ref(1) reads all commands as a single block of up
to 1000 characters and only starts processing after stdin gets closed.
This is less flexible than one might wish for, as it doesn't really
allow for longer-lived transactions and doesn't allow any verification
without committing everything. E.g. one may imagine the following
exchange:
> start
< start: ok
> update refs/heads/master $NEWOID1 $OLDOID1
> update refs/heads/branch $NEWOID2 $OLDOID2
> prepare
< prepare: ok
> commit
< commit: ok
When reading all input as a whole block, the above interactive protocol
is obviously impossible to achieve. But by converting the command to
read commands linewise, we can make it more interactive than before.
Obviously, the linewise interface is only a first step in making
git-update-ref(1) work in a more transaction-oriented way. Missing is
most importantly support for transactional commands that manage the
current transaction.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
update-ref: move transaction handling into `update_refs_stdin()`
While the actual logic to update the transaction is handled in
`update_refs_stdin()`, the transaction itself is started and committed
in `cmd_update_ref()` itself. This makes it hard to handle transaction
abortion and commits as part of `update_refs_stdin()` itself, which is
required in order to introduce transaction handling features to `git
update-refs --stdin`.
Refactor the code to move all transaction handling into
`update_refs_stdin()` to prepare for transaction handling features.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
We currently pass both an `strbuf` containing the current command line
as well as the `next` pointer pointing to the first argument to
commands. This is both confusing and makes code more intertwined.
Convert this to use a simple pointer as well as a pointer pointing to
the end of the input as a preparatory step to line-wise reading of
stdin.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
update-ref: drop unused argument for `parse_refname`
The `parse_refname` function accepts a `struct strbuf *input` argument
that isn't used at all. As we're about to convert commands to not use a
strbuf anymore but instead an end pointer, let's drop this argument now
to make the converting commit easier to review.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
We currently manually wire up all commands known to `git-update-ref
--stdin`, making it harder than necessary to preprocess arguments after
the command is determined. To make this more extensible, let's refactor
the code to use an array of known commands instead. While this doesn't
add a lot of value now, it is a preparatory step to implement line-wise
reading of commands.
As we're going to introduce commands without trailing spaces, this
commit also moves whitespace parsing into the respective commands.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
SZEDER Gábor [Thu, 2 Apr 2020 13:04:00 +0000 (20:04 +0700)]
ci: make MAKEFLAGS available inside the Docker container in the Linux32 job
Once upon a time we ran 'make --jobs=2 ...' to build Git, its
documentation, or to apply Coccinelle semantic patches. Then commit eaa62291ff (ci: inherit --jobs via MAKEFLAGS in run-build-and-tests,
2019-01-27) came along, and started using the MAKEFLAGS environment
variable to centralize setting the number of parallel jobs in
'ci/libs.sh'. Alas, it forgot to update 'ci/run-linux32-docker.sh' to
make MAKEFLAGS available inside the Docker container running the 32
bit Linux job, and, consequently, since then that job builds Git
sequentially, and it ignores any Makefile knobs that we might set in
MAKEFLAGS (though we don't set any for the 32 bit Linux job at the
moment).
So update the 'docker run' invocation in 'ci/run-linux32-docker.sh' to
make MAKEFLAGS available inside the Docker container as well. Set
CC=gcc for the 32 bit Linux job, because that's the compiler installed
in the 32 bit Linux Docker image that we use (Travis CI nowadays sets
CC=clang by default, but clang is not installed in this image).
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com> Signed-off-by: Đoàn Trần Công Danh <congdanhqx@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
t5319: replace 'touch -m' with 'test-tool chmtime'
The use of 'touch -m' to modify a file's mtime is slightly less
portable than using our own 'test-tool chmtime'. The important
thing is that these pack-files are ordered in a special way to
ensure the multi-pack-index selects some as the "newer" pack-files
when resolving duplicate objects.
Reported-by: Jeff King <peff@peff.net> Signed-off-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
The commit-graph builtin has an --expire-time option that takes a
datetime using OPT_EXPIRY_DATE(). However, the implementation inside
expire_commit_graphs() was treating a non-zero value as a number of
seconds to subtract from "now".
Update t5323-split-commit-graph.sh to demonstrate the correct value
of the --expire-time option by actually creating a crud .graph file
with mtime earlier than the expire time. Instead of using a super-
early time (1980) we use an explicit, and recent, time. Using
test-tool chmtime to create two files on either end of an exact
second, we create a test that catches this failure no matter the
current time. Using a fixed date is more portable than trying to
format a relative date string into the --expiry-date input.
I noticed this when inspecting some Scalar repos that had an excess
number of commit-graph files. In Scalar, we were using this second
interpretation by using "--expire-time=3600" to mean "delete graphs
older than one hour ago" to avoid deleting a commit-graph that a
foreground process may be trying to load.
Also I noticed that the help text was copied from the --max-commits
option. Fix that help text.
Signed-off-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
completion: fix 'git add' on paths under an untracked directory
As reported on the git mailing list, since git-2.25,
git add untracked-dir/
has been tab completing to
git add untracked-dir/./
The cause for this was that with commit b9670c1f5e (dir: fix checks on
common prefix directory, 2019-12-19),
git ls-files -o --directory untracked-dir/
(or the equivalent `git -C untracked-dir ls-files -o --directory`) began
reporting
untracked-dir/
instead of listing paths underneath that directory. It may also be
worth noting that the real command in question was
git -C untracked-dir ls-files -o --directory '*'
which is equivalent to
git ls-files -o --directory 'untracked-dir/*'
which behaves the same for the purposes of this issue (the '*' can match
the empty string), but becomes relevant for the proposed fix.
At first, based on the report, I decided to try to view this as a
regression and tried to find a way to recover the old behavior without
breaking other stuff, or at least breaking as little as possible.
However, in the end, I couldn't figure out a way to do it that wouldn't
just cause lots more problems than it solved. The old behavior was a
bug:
* Although older git would avoid cleaning anything with `git clean -f
.git`, it would wipe out everything under that direcotry with `git
clean -f .git/`. Despite the difference in command used, this is
relevant because the exact same change that fixed clean changed the
behavior of ls-files.
* Older git would report different results based solely on presence or
absence of a trailing slash for $SUBDIR in the command `git ls-files
-o --directory $SUBDIR`.
* Older git violated the documented behavior of not recursing into
directories that matched the pathspec when --directory was
specified.
* And, after all, commit b9670c1f5e (dir: fix checks on common prefix
directory, 2019-12-19) didn't overlook this issue; it explicitly
stated that the behavior of the command was being changed to bring
it inline with the docs.
(Also, if it helps, despite that commit being merged during the 2.25
series, this bug was not reported during the 2.25 cycle, nor even during
most of the 2.26 cycle -- it was reported a day before 2.26 was
released. So the impact of the change is at least somewhat small.)
Instead of relying on a bug of ls-files in reporting the wrong content,
change the invocation of ls-files used by git-completion to make it grab
paths one depth deeper. Do this by changing '$DIR/*' (match $DIR/ plus
0 or more characters) into '$DIR/?*' (match $DIR/ plus 1 or more
characters). Note that the '?' character should not be added when
trying to complete a filename (e.g. 'git ls-files -o --directory
"merge.c?*"' would not correctly return "merge.c" when such a file
exists), so we have to make sure to add the '?' character only in cases
where the path specified so far is a directory.
Signed-off-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Fix error-prone fill_directory() API; make it only return matches
Traditionally, the expected calling convention for the dir.c API was:
fill_directory(&dir, ..., pathspec)
foreach entry in dir->entries:
if (dir_path_match(entry, pathspec))
process_or_display(entry)
This may have made sense once upon a time, because the fill_directory() call
could use cheap checks to avoid doing full pathspec matching, and an external
caller may have wanted to do other post-processing of the results anyway.
However:
* this structure makes it easy for users of the API to get it wrong
* this structure actually makes it harder to understand
fill_directory() and the functions it uses internally. It has
tripped me up several times while trying to fix bugs and
restructure things.
* relying on post-filtering was already found to produce wrong
results; pathspec matching had to be added internally for multiple
cases in order to get the right results (see commits 404ebceda01c
(dir: also check directories for matching pathspecs, 2019-09-17)
and 89a1f4aaf765 (dir: if our pathspec might match files under a
dir, recurse into it, 2019-09-17))
* it's bad for performance: fill_directory() already has to do lots
of checks and knows the subset of cases where it still needs to do
more checks. Forcing external callers to do full pathspec
matching means they must re-check _every_ path.
So, add the pathspec matching within the fill_directory() internals, and
remove it from external callers.
Signed-off-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
projects / thirdparty / git.git / log
