The file 'dir/subdir/file' can only be modified if its leading
directories 'dir' and 'dir/subdir' are modified as well.
So when checking modified path Bloom filters looking for commits
modifying a path with multiple path components, then check not only
the full path in the Bloom filters, but all its leading directories as
well. Take care to check these paths in "deepest first" order,
because it's the full path that is least likely to be modified, and
the Bloom filter queries can short circuit sooner.
This can significantly reduce the average false positive rate, by
about an order of magnitude or three(!), and can further speed up
pathspec-limited revision walks. The table below compares the average
false positive rate and runtime of
git rev-list HEAD -- "$path"
before and after this change for 5000+ randomly* selected paths from
each repository:
Average false Average Average
positive rate runtime runtime
before after before after difference
------------------------------------------------------------------
git 3.220% 0.7853% 0.0558s 0.0387s -30.6%
linux 2.453% 0.0296% 0.1046s 0.0766s -26.8%
tensorflow 2.536% 0.6977% 0.0594s 0.0420s -29.2%
*Path selection was done with the following pipeline:
git ls-tree -r --name-only HEAD | sort -R | head -n 5000
The improvements in runtime are much smaller than the improvements in
average false positive rate, as we are clearly reaching diminishing
returns here. However, all these timings depend on that accessing
tree objects is reasonably fast (warm caches). If we had a partial
clone and the tree objects had to be fetched from a promisor remote,
e.g.:
$ git clone --filter=tree:0 --bare file://.../webkit.git webkit.notrees.git
$ git -C webkit.git -c core.modifiedPathBloomFilters=1 \
commit-graph write --reachable
$ cp webkit.git/objects/info/commit-graph webkit.notrees.git/objects/info/
$ git -C webkit.notrees.git -c core.modifiedPathBloomFilters=1 \
rev-list HEAD -- "$path"
then checking all leading path component can reduce the runtime from
over an hour to a few seconds (and this is with the clone and the
promisor on the same machine).
This adjusts the tracing values in t4216-log-bloom.sh, which provides a
concrete way to notice the improvement.
Helped-by: Taylor Blau <me@ttaylorr.com>
Helped-by: René Scharfe <l.s.r@web.de>
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The prepare_to_use_bloom_filter() method was not intended to be called
on an empty pathspec. However, 'git log -- .' and 'git log' are subtly
different: the latter reports all commits while the former will simplify
commits that do not change the root tree.
This means that the path used to construct the bloom_key might be empty,
and that value is not added to the Bloom filter during construction.
That means that the results are likely incorrect!
To resolve the issue, be careful about the length of the path and stop
filling Bloom filters. To be completely sure we do not use them, drop
the pointer to the bloom_filter_settings from the commit-graph. That
allows our test to look at the trace2 logs to verify no Bloom filter
statistics are reported.
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The changed-path Bloom filters were released in v2.27.0, but have a
significant drawback. A user can opt-in to writing the changed-path
filters using the "--changed-paths" option to "git commit-graph write"
but the next write will drop the filters unless that option is
specified.
This becomes even more important when considering the interaction with
gc.writeCommitGraph (on by default) or fetch.writeCommitGraph (part of
features.experimental). These config options trigger commit-graph writes
that the user did not signal, and hence there is no --changed-paths
option available.
Allow a user that opts-in to the changed-path filters to persist the
property of "my commit-graph has changed-path filters" automatically. A
user can drop filters using the --no-changed-paths option.
In the process, we need to be extremely careful to match the Bloom
filter settings as specified by the commit-graph. This will allow future
versions of Git to customize these settings, and the version with this
change will persist those settings as commit-graphs are rewritten on
top.
Use the trace2 API to signal the settings used during the write, and
check that output in a test after manually adjusting the correct bytes
in the commit-graph file.
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The get_bloom_filter() method is a bit complicated in some parts where
it does not need to be. In particular, it needs to return a NULL filter
only when compute_if_not_present is zero AND the filter data cannot be
loaded from a commit-graph file. This currently happens by accident
because the commit-graph does not load changed-path Bloom filters from
an existing commit-graph when writing a new one. This will change in a
later patch.
Also clean up some style issues while we are here.
One side-effect of returning a NULL filter is that the filters that are
reported as "too large" will now be reported as NULL insead of length
zero. This case was not properly covered before, so add a test. Further,
remote the counting of the zero-length filters from revision.c and the
trace2 logs.
Helped-by: René Scharfe <l.s.r@web.de>
Helped-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"git diff-files" has been taught to say paths that are marked as
intent-to-add are new files, not modified from an empty blob.
* sk/diff-files-show-i-t-a-as-new:
diff-files: treat "i-t-a" files as "not-in-index"
Allow runtime upgrade of the repository format version, which needs
to be done carefully.
There is a rather unpleasant backward compatibility worry with the
last step of this series, but it is the right thing to do in the
longer term.
* xl/upgrade-repo-format:
check_repository_format_gently(): refuse extensions for old repositories
sparse-checkout: upgrade repository to version 1 when enabling extension
fetch: allow adding a filter after initial clone
repository: add a helper function to perform repository format upgrade
Running "fast-export --anonymize" will leave "refs/heads/master"
untouched in the output, for two reasons:
- it helped to have some known reference point between the original
and anonymized repository
- since it's historically the default branch name, it doesn't leak any
information
Now that we can ask fast-export to retain particular tokens, we have a
much better tool for the first one (because it works for any ref, not
just master).
For the second, the notion of "default branch name" is likely to become
configurable soon, at which point the name _does_ leak information.
Let's drop this special case in preparation.
Note that we have to adjust the test a bit, since it relied on using the
name "master" in the anonymized repos. We could just use
--anonymize-map=master to keep the same output, but then we wouldn't
know if it works because of our hard-coded master or because of the
explicit map.
So let's flip the test a bit, and confirm that we anonymize "master",
but keep "other" in the output.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
After you anonymize a repository, it can be hard to find which commits
correspond between the original and the result, and thus hard to
reproduce commands that triggered bugs in the original.
Let's make it possible to seed the anonymization map. This lets users
either:
- mark names to be retained as-is, if they don't consider them secret
(in which case their original commands would just work)
- map names to new values, which lets them adapt the reproduction
recipe to the new names without revealing the originals
The implementation is fairly straight-forward. We already store each
anonymized token in a hashmap (so that the same token appearing twice is
converted to the same result). We can just introduce a new "seed"
hashmap which is consulted first.
This does make a few more promises to the user about how we'll anonymize
things (e.g., token-splitting pathnames). But it's unlikely that we'd
want to change those rules, even if the actual anonymization of a single
token changes. And it makes things much easier for the user, who can
unblind only a directory name without having to specify each path within
it.
One alternative to this approach would be to anonymize as we see fit,
and then dump the whole refname and pathname mappings to a file. This
does work, but it's a bit awkward to use (you have to manually dig the
items you care about out of the mapping).
Helped-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The "fetch/clone" protocol has been updated to allow the server to
instruct the clients to grab pre-packaged packfile(s) in addition
to the packed object data coming over the wire.
* jt/cdn-offload:
upload-pack: fix a sparse '0 as NULL pointer' warning
upload-pack: send part of packfile response as uri
fetch-pack: support more than one pack lockfile
upload-pack: refactor reading of pack-objects out
Documentation: add Packfile URIs design doc
Documentation: order protocol v2 sections
http-fetch: support fetching packfiles by URL
http-fetch: refactor into function
http: refactor finish_http_pack_request()
http: use --stdin when indexing dumb HTTP pack
Code clean-up around "git branch" with a minor bugfix.
* dl/branch-cleanup:
branch: don't mix --edit-description
t3200: test for specific errors
t3200: rename "expected" to "expect"
"git diff" used to take arguments in random and nonsense range
notation, e.g. "git diff A..B C", "git diff A..B C...D", etc.,
which has been cleaned up.
* ct/diff-with-merge-base-clarification:
Documentation: usage for diff combined commits
git diff: improve range handling
t/t3430: avoid undefined git diff behavior
As our test suite partially reflects how we work in the Git project, it
is natural that the branch name `pu` was used in a couple places.
Since that branch was renamed to `seen`, let's use the new name
consistently.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The default name of the initial branch in new repositories can now be
configured. The `testsvn` remote helper translates the remote Subversion
repository's branch name `trunk` to the hard-coded name `master`.
Clearly, the intention was to make the name align with Git's defaults.
So while we are not talking about a newly-created repository in the
`testsvn` context, it is a newly-created _Git_ repository, si it _still_
makes sense to use the overridden default name for the initial branch
whenever users configured it.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When guessing the default branch name of a remote, and there are no refs
to guess from, we want to go with the preference specified by the user
for the fall-back, i.e. the default name to be used for the initial
branch of new repositories (because as far as the user is concerned, a
remote that has no branches yet is a new repository).
At the same time, when talking to an older Git server that does not
report a symref for `HEAD` (but instead reports a commit hash), let's
try to guess the configured default branch name first. If it does not
match the reported commit hash, let's fall back to `master` as before.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When cloning a repository without any branches, Git chooses a default
branch name for the as-yet unborn branch.
As part of the implicit initialization of the local repository, Git just
learned to respect `init.defaultBranch` to choose a different initial
branch name. We now really want that branch name to be used as a
fall-back.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We just introduced the command-line option
`--initial-branch=<branch-name>` to allow initializing a new repository
with a different initial branch than the hard-coded one.
To allow users to override the initial branch name more permanently
(i.e. without having to specify the name manually for each and every
`git init` invocation), let's introduce the `init.defaultBranch` config
setting.
Helped-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Helped-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Don Goodman-Wilson <don@goodman-wilson.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
There is a growing number of projects and companies desiring to change
the main branch name of their repositories (see e.g.
https://twitter.com/mislav/status/1270388510684598272 for background on
this).
To change that branch name for new repositories, currently the only way
to do that automatically is by copying all of Git's template directory,
then hard-coding the desired default branch name into the `.git/HEAD`
file, and then configuring `init.templateDir` to point to those copied
template files.
To make this process much less cumbersome, let's introduce a new option:
`--initial-branch=<branch-name>`.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When `remote.<name>.branch` is not configured, `git submodule update`
currently falls back to using the branch name `master`. A much better
idea, however, is to use the remote `HEAD`: on all Git servers running
reasonably recent Git versions, the symref `HEAD` points to the main
branch.
Note: t7419 demonstrates that there _might_ be use cases out there that
_expect_ `git submodule update --remote` to update submodules to the
remote `master` branch even if the remote `HEAD` points to another
branch. Arguably, this patch makes the behavior more intuitive, but
there is a slight possibility that this might cause regressions in
obscure setups.
Even so, it should be okay to fix this behavior without anything like a
longer transition period:
- The `git submodule update --remote` command is not really common.
- Current Git's behavior when running this command is outright
confusing, unless the remote repository's current branch _is_ `master`
(in which case the proposed behavior matches the old behavior).
- If a user encounters a regression due to the changed behavior, the fix
is actually trivial: setting `submodule.<name>.branch` to `master`
will reinstate the old behavior.
Helped-by: Philippe Blain <levraiphilippeblain@gmail.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When trying to push all matching branches, but none match, we offer a
message suggesting to push the `master` branch.
However, we want to step away from making that branch any more special
than any other branch, so let's reword that message to mention no branch
in particular.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When we run a test helper function in test_submodule_switch_common(), we
sometimes specify a whole helper function as the $command. When we do
this, in some test cases, we just mark the whole function with
`test_must_fail`. However, it's possible that the helper function might
fail earlier or later than expected due to an introduced bug. If this
happens, then the test case will still report as passing but it should
really be marked as failing since it didn't actually display the
intended behaviour.
Instead of invoking `test_must_fail $command`, pass the string
"test_must_fail" as the second argument in case where the git command is
expected to fail.
When $command is a helper function, the parent function calling
test_submodule_switch_common() is test_submodule_switch_func(). For all
test_submodule_switch_func() invocations, increase the granularity of
the argument test helper function by prefixing the git invocation which is
meant to fail with the second argument like this:
$2 git checkout "$1"
In the other cases, test_submodule_switch() and
test_submodule_forced_switch(), instead of passing in the git command
directly, wrap it using the git_test_func() and pass the git arguments
using the global variable $gitcmd. Unfortunately, since closures aren't
a thing in shell scripts, the global variable is necessary. Another
unfortunate result is that the "git_test_func" will used as the test
case name when $command is printed but it's worth it for the cleaner
code.
Finally, as an added bonus, `test_must_fail` will now only run on git
commands.
Signed-off-by: Denton Liu <liu.denton@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Our anonymize_mem() function is careful to take a ptr/len pair to allow
storing binary tokens like object ids, as well as partial strings (e.g.,
just "foo" of "foo/bar"). But it duplicates the hash key using
xstrdup()! That means that:
- for a partial string, we'd store all bytes up to the NUL, even
though we'd never look at anything past "len". This didn't produce
wrong behavior, but was wasteful.
- for a binary oid that doesn't contain a zero byte, we'd copy garbage
bytes off the end of the array (though as long as nothing complained
about reading uninitialized bytes, further reads would be limited by
"len", and we'd produce the correct results)
- for a binary oid that does contain a zero byte, we'd copy _fewer_
bytes than intended into the hashmap struct. When we later try to
look up a value, we'd access uninitialized memory and potentially
falsely claim that a particular oid is not present.
The most common reason to store an oid is an anonymized gitlink, but our
test case doesn't have any gitlinks at all. So let's add one whose oid
contains a NUL and is present at two different paths. ASan catches the
memory error, but even without it we can detect the bug because the oid
is not anonymized the same way for both paths.
And of course the fix is to copy the correct number of bytes. We don't
technically need the appended NUL from xmemdupz(), but it doesn't hurt
as an extra protection against anybody treating it like a string (plus a
future patch will push us more in that direction).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Our tests of the anonymized repo just hard-code the expected set of
objects in the root and subdirectory trees. This makes them brittle to
the test setup changing (e.g., adding new paths that need tested).
Let's look at the original repo to compute our expected set of objects.
Note that this isn't completely perfect (e.g., we still rely on there
being only one tree in the root), but it does simplify later patches.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In the context of many projects renaming their primary branch names away
from `master`, Git wants to stop treating the `master` branch specially.
Let's start with `git fmt-merge-msg`.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
43d3561 (commit-graph write: don't die if the existing graph is corrupt,
2019-03-25) introduced the GIT_TEST_COMMIT_GRAPH_DIE_ON_LOAD environment
variable. This was created to verify that commit-graph was not loaded
when writing a new non-incremental commit-graph.
An upcoming change wants to load a commit-graph in some valuable cases,
but we want to maintain that we don't trust the commit-graph data when
writing our new file. Instead of dying on load, instead die if we ever
try to parse a commit from the commit-graph. This functionally verifies
the same intended behavior, but allows a more advanced feature in the
next change.
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
d91d6fbf26 (commit-reach: create repo_is_descendant_of(), 2020-06-17)
adds a repository aware version of is_descendant_of() and a backward
compatibility shim that is barely used.
Update all callers to directly use the new repo_is_descendant_of()
function instead; making the codebase simpler and pushing more
the_repository references higher up the stack.
Helped-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Carlo Marcelo Arenas Belón <carenas@gmail.com>
Reviewed-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When we push using the DAV-based protocol, the client is the one that
performs the ref updates and therefore makes the checks to see whether
an unforced push should be allowed. We make this check by determining
if either (a) we lack the object file for the old value of the ref or
(b) the new value of the ref is not newer than the old value, and in
either case, reject the push.
However, the ref_newer function, which performs this latter check, has
an odd behavior due to the reuse of certain object flags. Specifically,
it will incorrectly return false in its first invocation and then
correctly return true on a subsequent invocation. This occurs because
the object flags used by http-push.c are the same as those used by
commit-reach.c, which implements ref_newer, and one piece of code
misinterprets the flags set by the other.
Note that this does not occur in all cases. For example, if the example
used in the tests is changed to use one repository instead of two and
rewind the head to add a commit, the test passes and we correctly reject
the push. However, the example provided does trigger this behavior, and
the code has been broken in this way since at least Git 2.0.0.
To solve this problem, let's move the two sets of object flags so that
they don't overlap, since we're clearly using them at the same time.
The new set should not conflict with other usage because other users are
either builtin code (which is not compiled into git http-push) or
upload-pack (which we similarly do not use here).
Reported-by: Michael Ward <mward@smartsoftwareinc.com>
Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The same worktree directory must be registered only once, but
"git worktree move" allowed this invariant to be violated, which
has been corrected.
* es/worktree-duplicate-paths:
worktree: make "move" refuse to move atop missing registered worktree
worktree: generalize candidate worktree path validation
worktree: prune linked worktree referencing main worktree path
worktree: prune duplicate entries referencing same worktree path
worktree: make high-level pruning re-usable
worktree: give "should be pruned?" function more meaningful name
worktree: factor out repeated string literal
The interface to redact sensitive information in the trace output
has been simplified.
* jt/redact-all-cookies:
http: redact all cookies, teach GIT_TRACE_REDACT=0
The record size used in the git svn storage is four bytes plus the
length of the binary hash. Pass the hash length into our Perl
invocation and use it to compute the size of the records.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Acked-by: Eric Wong <e@80x24.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The `diff-files' command and related commands which call the function
`cmd_diff_files()', consider the "intent-to-add" files as a part of the
index when comparing the work-tree against it. This was previously
addressed in commits [1] and [2] by turning the option
`--ita-invisible-in-index' (introduced in [3]) on by default.
For `diff-files' (and `add -p' as a consequence) to show the i-t-a
files as as new, `ita_invisible_in_index' will be enabled by default
here as well.
[1] 0231ae71d3 (diff: turn --ita-invisible-in-index on by default,
2018-05-26)
[2] 425a28e0a4 (diff-lib: allow ita entries treated as "not yet exist
in index", 2016-10-24)
[3] b42b451919 (diff: add --ita-[in]visible-in-index, 2016-10-24)
Signed-off-by: Srinidhi Kaushik <shrinidhi.kaushik@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
get_worktrees() accepts a 'flags' argument, however, there are no
existing flags (the lone flag GWT_SORT_LINKED was recently retired) and
no behavior which can be tweaked. Therefore, drop the 'flags' argument.
Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Instead of hard-coding the object ID for our test .gitignore file, let's
compute it.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Acked-by: Eric Wong <e@80x24.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The size of a record in the database used by git svn is four bytes plus
the length of the binary hash. Instead of hard-coding 24, compute this
value based on the size of the hash in use.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Acked-by: Eric Wong <e@80x24.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Compute the relevant tree objects for SHA-256 and use those when
appropriate instead of using the SHA-1 ones.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Acked-by: Eric Wong <e@80x24.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Instead of stripping off the first 41 characters of git log output,
let's just strip off the first space-separated component, which will
work for any size hash.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Acked-by: Eric Wong <e@80x24.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Instead of stripping off the first 41 characters of git log output,
let's just strip off the first space-separated component, which will
work for any size hash.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Acked-by: Eric Wong <e@80x24.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Instead of stripping off the first 41 characters of git log output,
let's just strip off the first space-separated component, which will
work for any size hash.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Acked-by: Eric Wong <e@80x24.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When using an algorithm other than SHA-1, we need the remote helper to
advertise support for the object-format extension and provide
information back to us so that we can properly parse refs and return
data. Ensure that the test remote helper understands these extensions.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
git index-pack by default reads the repository to determine the object
format. However, when outside of a repository, it's necessary to specify
the hash algorithm in use so that the pack can be properly indexed. Add
an --object-format argument when invoking git index-pack outside of a
repository.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When we speak protocol v2 in this test, we must pass the object-format
header if the algorithm is not SHA-1. Otherwise, git upload-pack fails
because the hash algorithm doesn't match and not because we've failed to
speak the protocol correctly. Pass the header so that our assertions
test what we're really interested in.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When we're using an algorithm other than SHA-1, we need to specify the
algorithm in use so we don't get a failure with an "unknown format"
message. Add a wrapper function that specifies this header if required.
Skip specifying this header for SHA-1 to test that it works both with an
without this header.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In order to make this test work with SHA-256, offer an object-format
capability so that both sides use the same algorithm.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
test-sha1-array uses the_hash_algo under the hood. Since t0064 wants to
use the value that is correct for the hash algorithm that we're testing,
make sure the test helper initializes the repository to set
the_hash_algo correctly.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When outside a repository, git index-pack is unable to guess the hash
algorithm in use for a pack, since packs don't contain any information
on the algorithm in use. Pass an option to index-pack to help it out in
this test.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When reading the info/refs file for a repository, we have no explicit
way to detect which hash algorithm is in use because the file doesn't
provide one. Detect the hash algorithm in use by the size of the first
object ID.
If we have an empty repository, we don't know what the hash algorithm is
on the remote side, so default to whatever the local side has
configured. Without doing this, we cannot clone an empty repository
since we don't know its hash algorithm. Test this case appropriately,
since we currently have no tests for cloning an empty repository with
the dumb HTTP protocol.
We anonymize the URL like elsewhere in the function in case the user has
decided to include a secret in the URL.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The low-level reference transactions used to update references are
currently completely opaque to the user. While certainly desirable in
most usecases, there are some which might want to hook into the
transaction to observe all queued reference updates as well as observing
the abortion or commit of a prepared transaction.
One such usecase would be to have a set of replicas of a given Git
repository, where we perform Git operations on all of the repositories
at once and expect the outcome to be the same in all of them. While
there exist hooks already for a certain subset of Git commands that
could be used to implement a voting mechanism for this, many others
currently don't have any mechanism for this.
The above scenario is the motivation for the new "reference-transaction"
hook that reaches directly into Git's reference transaction mechanism.
The hook receives as parameter the current state the transaction was
moved to ("prepared", "committed" or "aborted") and gets via its
standard input all queued reference updates. While the exit code gets
ignored in the "committed" and "aborted" states, a non-zero exit code in
the "prepared" state will cause the transaction to be aborted
prematurely.
Given the usecase described above, a voting mechanism can now be
implemented via this hook: as soon as it gets called, it will take all
of stdin and use it to cast a vote to a central service. When all
replicas of the repository agree, the hook will exit with zero,
otherwise it will abort the transaction by returning non-zero. The most
important upside is that this will catch _all_ commands writing
references at once, allowing to implement strong consistency for
reference updates via a single mechanism.
In order to test the impact on the case where we don't have any
"reference-transaction" hook installed in the repository, this commit
introduce two new performance tests for git-update-refs(1). Run against
an empty repository, it produces the following results:
Test origin/master HEAD
--------------------------------------------------------------------
1400.2: update-ref 2.70(2.10+0.71) 2.71(2.10+0.73) +0.4%
1400.3: update-ref --stdin 0.21(0.09+0.11) 0.21(0.07+0.14) +0.0%
The performance test p1400.2 creates, updates and deletes a branch a
thousand times, thus averaging runtime of git-update-refs over 3000
invocations. p1400.3 instead calls `git-update-refs --stdin` three times
and queues a thousand creations, updates and deletes respectively.
As expected, p1400.3 consistently shows no noticeable impact, as for
each batch of updates there's a single call to access(3P) for the
negative hook lookup. On the other hand, for p1400.2, one can see an
impact caused by this patchset. But doing five runs of the performance
tests where each one was run with GIT_PERF_REPEAT_COUNT=10, the overhead
ranged from -1.5% to +1.1%. These inconsistent performance numbers can
be explained by the overhead of spawning 3000 processes. This shows that
the overhead of assembling the hook path and executing access(3P) once
to check if it's there is mostly outweighed by the operating system's
overhead.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Git branches have been qualified as topic branches, integration branches,
development branches, feature branches, release branches and so on.
Git has a branch that is the master *for* development, but it is not
the master *of* any "slave branch": Git does not have slave branches,
and has never had, except for a single testcase that claims otherwise. :)
Independent of any future change to the naming of the "master" branch,
removing this sole appearance of the term is a strict improvement: it
avoids divisive language, and talking about "feature branch" clarifies
which developer workflow the test is trying to emulate.
Reported-by: Till Maas <tmaas@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
