887952b8c6 ("fetch: optionally allow disabling FETCH_HEAD update",
2020-08-18) introduced the ability to disable writing to FETCH_HEAD
during fetch, but did not suppress the "<source> -> FETCH_HEAD" message
when this ability is used. This message is misleading in this case,
because FETCH_HEAD is not written. Also, because "fetch" is used to
lazy-fetch missing objects in a partial clone, this significantly
clutters up the output in that case since the objects to be fetched are
potentially numerous.
Therefore, suppress this message when --no-write-fetch-head is passed
(but not when --dry-run is set).
Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Teach Git to lazy-fetch missing objects in a subprocess instead of doing
it in-process. This allows any fatal errors that occur during the fetch
to be isolated and converted into an error return value, instead of
causing the current command being run to terminate.
Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
These tests try to check that we behave properly if we encounter a
repository with version 0 but an extension. This is a laudable goal,
but the test cannot work with SHA-256, since SHA-256 repositories always
have an existing extension and are never version 0.
Add a SHA1 prerequisite to these tests.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Reviewed-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Now that we officially permit repository extensions in repository
format v0, permit upgrading a repository with extensions from v0 to v1
as well.
For example, this means a repository where the user has set
"extensions.preciousObjects" can use "git fetch --filter=blob:none
origin" to upgrade the repository to use v1 and the partial clone
extension.
To avoid mistakes, continue to forbid repository format upgrades in v0
repositories with an unrecognized extension. This way, a v0 user
using a misspelled extension field gets a chance to correct the
mistake before updating to the less forgiving v1 format.
While we're here, make the error message for failure to upgrade the
repository format a bit shorter, and present it as an error, not a
warning.
Reported-by: Huan Huan Chen <huanhuanchen@google.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This reverts commit 14c7fa269e.
The core.repositoryFormatVersion field was introduced in ab9cb76f66
(Repository format version check., 2005-11-25), providing a welcome
bit of forward compatibility, thanks to some welcome analysis by
Martin Atukunda. The semantics are simple: a repository with
core.repositoryFormatVersion set to 0 should be comprehensible by all
Git implementations in active use; and Git implementations should
error out early instead of trying to act on Git repositories with
higher core.repositoryFormatVersion values representing new formats
that they do not understand.
A new repository format did not need to be defined until 00a09d57eb
(introduce "extensions" form of core.repositoryformatversion,
2015-06-23). This provided a finer-grained extension mechanism for
Git repositories. In a repository with core.repositoryFormatVersion
set to 1, Git implementations can act on "extensions.*" settings that
modify how a repository is interpreted. In repository format version
1, unrecognized extensions settings cause Git to error out.
What happens if a user sets an extension setting but forgets to
increase the repository format version to 1? The extension settings
were still recognized in that case; worse, unrecognized extensions
settings do *not* cause Git to error out. So combining repository
format version 0 with extensions settings produces in some sense the
worst of both worlds.
To improve that situation, since 14c7fa269e
(check_repository_format_gently(): refuse extensions for old
repositories, 2020-06-05) Git instead ignores extensions in v0 mode.
This way, v0 repositories get the historical (pre-2015) behavior and
maintain compatibility with Git implementations that do not know about
the v1 format. Unfortunately, users had been using this sort of
configuration and this behavior change came to many as a surprise:
- users of "git config --worktree" that had followed its advice
to enable extensions.worktreeConfig (without also increasing the
repository format version) would find their worktree configuration
no longer taking effect
- tools such as copybara[*] that had set extensions.partialClone in
existing repositories (without also increasing the repository format
version) would find that setting no longer taking effect
The behavior introduced in 14c7fa269e might be a good behavior if we
were traveling back in time to 2015, but we're far too late. For some
reason I thought that it was what had been originally implemented and
that it had regressed. Apologies for not doing my research when
14c7fa269e was under development.
Let's return to the behavior we've had since 2015: always act on
extensions.* settings, regardless of repository format version. While
we're here, include some tests to describe the effect on the "upgrade
repository version" code path.
[*] ca76c0b1e1
Reported-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Previously, extensions were recognized regardless of repository format
version. If the user sets an undefined "extensions" value on a
repository of version 0 and that value is used by a future git version,
they might get an undesired result.
Because all extensions now also upgrade repository versions, tightening
the check would help avoid this for future extensions.
Signed-off-by: Xin Li <delphij@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Retroactively adding a filter can be useful for existing shallow clones as
they allow users to see earlier change histories without downloading all
git objects in a regular --unshallow fetch.
Without this patch, users can make a clone partial by editing the
repository configuration to convert the remote into a promisor, like:
git config core.repositoryFormatVersion 1
git config extensions.partialClone origin
git fetch --unshallow --filter=blob:none origin
Since the hard part of making this work is already in place and such
edits can be error-prone, teach Git to perform the required configuration
change automatically instead.
Note that this change does not modify the existing git behavior which
recognizes setting extensions.partialClone without changing
repositoryFormatVersion.
Signed-off-by: Xin Li <delphij@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The cache-tree code has been taught to be less aggressive in
attempting to see if a tree object it computed already exists in
the repository.
* jt/cache-tree-avoid-lazy-fetch-during-merge:
cache-tree: do not lazy-fetch tentative tree
Previously, when promisor_remote_move_to_tail() is called for a
promisor_remote which is currently the final element in promisors, a
cycle is created in the promisors linked list. This cycle leads to a
double free later on in promisor_remote_clear() when the final element
of the promisors list is removed: promisors is set to promisors->next (a
no-op, as promisors->next == promisors); the previous value of promisors
is free()'d; then the new value of promisors (which is equal to the
previous value of promisors) is also free()'d. This double-free error
was unrecoverable for the user without removing the filter or re-cloning
the repo and hoping to miss this edge case.
Now, when promisor_remote_move_to_tail() would be a no-op, just do a
no-op. In cases of promisor_remote_move_to_tail() where r is not already
at the tail of the list, it works as before.
Helped-by: Jeff King <peff@peff.net>
Signed-off-by: Emily Shaffer <emilyshaffer@google.com>
Acked-by: Christian Couder <christian.couder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Teach the lazy clone machinery that there can be more than one
promisor remote and consult them in order when downloading missing
objects on demand.
* cc/multi-promisor:
Move core_partial_clone_filter_default to promisor-remote.c
Move repository_format_partial_clone to promisor-remote.c
Remove fetch-object.{c,h} in favor of promisor-remote.{c,h}
remote: add promisor and partial clone config to the doc
partial-clone: add multiple remotes in the doc
t0410: test fetching from many promisor remotes
builtin/fetch: remove unique promisor remote limitation
promisor-remote: parse remote.*.partialclonefilter
Use promisor_remote_get_direct() and has_promisor_remote()
promisor-remote: use repository_format_partial_clone
promisor-remote: add promisor_remote_reinit()
promisor-remote: implement promisor_remote_get_direct()
Add initial support for many promisor remotes
fetch-object: make functions return an error code
t0410: remove pipes after git commands
The cache-tree datastructure is used to speed up the comparison
between the HEAD and the index, and when the index is updated by
a cherry-pick (for example), a tree object that would represent
the paths in the index in a directory is constructed in-core, to
see if such a tree object exists already in the object store.
When the lazy-fetch mechanism was introduced, we converted this
"does the tree exist?" check into an "if it does not, and if we
lazily cloned, see if the remote has it" call by mistake. Since
the whole point of this check is to repair the cache-tree by
recording an already existing tree object opportunistically, we
shouldn't even try to fetch one from the remote.
Pass the OBJECT_INFO_SKIP_FETCH_OBJECT flag to make sure we only
check for existence in the local object store without triggering the
lazy fetch mechanism.
Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
[jc: rewritten the proposed log message]
Signed-off-by: Junio C Hamano <gitster@pobox.com>
A mechanism to affect the default setting for a (related) group of
configuration variables is introduced.
* ds/feature-macros:
repo-settings: create feature.experimental setting
repo-settings: create feature.manyFiles setting
repo-settings: parse core.untrackedCache
commit-graph: turn on commit-graph by default
t6501: use 'git gc' in quiet mode
repo-settings: consolidate some config settings
The commit-graph feature has seen a lot of activity in the past
year or so since it was introduced. The feature is a critical
performance enhancement for medium- to large-sized repos, and
does not significantly hurt small repos.
Change the defaults for core.commitGraph and gc.writeCommitGraph
to true so users benefit from this feature by default.
There are several places in the test suite where the environment
variable GIT_TEST_COMMIT_GRAPH is disabled to avoid reading a
commit-graph, if it exists. The config option overrides the
environment, so swap these. Some GIT_TEST_COMMIT_GRAPH assignments
remain, and those are to avoid writing a commit-graph when a new
commit is created.
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We have a couple of test scripts that are not completely
httpd-specific, but do run a few httpd-specific tests at the end.
These test scripts source 'lib-httpd.sh' somewhere mid-script, which
then skips all the rest of the test script if the dependencies for
running httpd tests are not fulfilled.
As the previous two patches in this series show, already on two
occasions non-httpd-specific tests were appended at the end of such
test scripts, and, consequently, they were skipped as well when httpd
tests couldn't be run.
Add a comment at the end of these test scripts to warn against adding
non-httpd-specific tests at the end, in the hope that they will help
prevent similar issues in the future.
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This shows that it is now possible to fetch objects from more
than one promisor remote, and that fetching from a new
promisor remote can configure it as one.
Helped-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This makes it possible to specify a different partial clone
filter for each promisor remote.
Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Let's not run a git command, especially one with "verify" in its
name, upstream of a pipe, because the pipe will hide the git
command's exit code.
While at it, let's also avoid a useless `cat` command piping
into `sed`.
Helped-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Use 'test_atexit' to run cleanup commands to stop httpd at the end of
the test script or upon interrupt or failure, as it is shorter,
simpler, and more robust than registering such cleanup commands in the
trap on EXIT in the test scripts.
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Flaky tests can now be repeatedly run under load with the
"--stress" option.
* sg/stress-test:
test-lib: add the '--stress' option to run a test repeatedly under load
test-lib-functions: introduce the 'test_set_port' helper function
test-lib: set $TRASH_DIRECTORY earlier
test-lib: consolidate naming of test-results paths
test-lib: parse command line options earlier
test-lib: parse options in a for loop to keep $@ intact
test-lib: extract Bash version check for '-x' tracing
test-lib: translate SIGTERM and SIGHUP to an exit
"git rev-list --exclude-promisor-objects" had to take an object
that does not exist locally (and is lazily available) from the
command line without barfing, but the code dereferenced NULL.
* md/list-lazy-objects-fix:
list-objects.c: don't segfault for missing cmdline objects
Several test scripts run daemons like 'git-daemon' or Apache, and
communicate with them through TCP sockets. To have unique ports where
these daemons are accessible, the ports are usually the number of the
corresponding test scripts, unless the user overrides them via
environment variables, and thus all those tests and test libs contain
more or less the same bit of one-liner boilerplate code to find out
the port. The last patch in this series will make this a bit more
complicated.
Factor out finding the port for a daemon into the common helper
function 'test_set_port' to avoid repeating ourselves.
Take special care of test scripts with "low" numbers:
- Test numbers below 1024 would result in a port that's only usable
as root, so set their port to '10000 + test-nr' to make sure it
doesn't interfere with other tests in the test suite. This makes
the hardcoded port number in 't0410-partial-clone.sh' unnecessary,
remove it.
- The shell's arithmetic evaluation interprets numbers with leading
zeros as octal values, which means that test number below 1000 and
containing the digits 8 or 9 will trigger an error. Remove all
leading zeros from the test numbers to prevent this.
Note that the 'git p4' tests are unlike the other tests involving
daemons in that:
- 'lib-git-p4.sh' doesn't use the test's number for unique port as
is, but does a bit of additional arithmetic on top [1].
- The port is not overridable via an environment variable.
With this patch even 'git p4' tests will use the test's number as
default port, and it will be overridable via the P4DPORT environment
variable.
[1] Commit fc00233071 (git-p4 tests: refactor and cleanup, 2011-08-22)
introduced that "unusual" unique port computation without
explaining why it was necessary (as opposed to simply using the
test number as is). It seems to be just unnecessary complication,
and in any case that commit came way before the "test nr as unique
port" got "standardized" for other daemons in commits c44132fcf3
(tests: auto-set git-daemon port, 2014-02-10), 3bb486e439 (tests:
auto-set LIB_HTTPD_PORT from test name, 2014-02-10), and
bf9d7df950 (t/lib-git-svn.sh: improve svnserve tests with parallel
make test, 2017-12-01).
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When a command is invoked with both --exclude-promisor-objects,
--objects-edge-aggressive, and a missing object on the command line,
the rev_info.cmdline array could get a NULL pointer for the value of
an 'item' field. Prevent dereferencing of a NULL pointer in that
situation.
Properly handle --ignore-missing. If it is not passed, die when an
object is missing. Otherwise, just silently ignore it.
Signed-off-by: Matthew DeVore <matvore@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The "rev-list --filter" feature learned to exclude all trees via
"tree:0" filter.
* md/filter-trees:
list-objects: support for skipping tree traversal
filter-trees: code clean-up of tests
list-objects-filter: implement filter tree:0
list-objects-filter-options: do not over-strbuf_init
list-objects-filter: use BUG rather than die
revision: mark non-user-given objects instead
rev-list: handle missing tree objects properly
list-objects: always parse trees gently
list-objects: refactor to process_tree_contents
list-objects: store common func args in struct
A partial clone that is configured to lazily fetch missing objects
will on-demand issue a "git fetch" request to the originating
repository to fill not-yet-obtained objects. The request has been
optimized for requesting a tree object (and not the leaf blob
objects contained in it) by telling the originating repository that
no blobs are needed.
* jt/non-blob-lazy-fetch:
fetch-pack: exclude blobs when lazy-fetching trees
fetch-pack: avoid object flags if no_dependents
Previously, we assumed only blob objects could be missing. This patch
makes rev-list handle missing trees like missing blobs. The --missing=*
and --exclude-promisor-objects flags now work for trees as they already
do for blobs. This is demonstrated in t6112.
Signed-off-by: Matthew DeVore <matvore@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
A partial clone with missing trees can be obtained using "git clone
--filter=tree:none <repo>". In such a repository, when a tree needs to
be lazily fetched, any tree or blob it directly or indirectly references
is fetched as well, regardless of whether the original command required
those objects, or if the local repository already had some of them.
This is because the fetch protocol, which the lazy fetch uses, does not
allow clients to request that only the wanted objects be sent, which
would be the ideal solution. This patch implements a partial solution:
specify the "blob:none" filter, somewhat reducing the fetch payload.
This change has no effect when lazily fetching blobs (due to how filters
work). And if lazily fetching a commit (such repositories are difficult
to construct and is not a use case we support very well, but it is
possible), referenced commits and trees are still fetched - only the
blobs are not fetched.
The necessary code change is done in fetch_pack() instead of somewhere
closer to where the "filter" instruction is written to the wire so that
only one part of the code needs to be changed in order for users of all
protocol versions to benefit from this optimization.
Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The code to backfill objects in lazily cloned repository did not
work correctly, which has been corrected.
* jt/lazy-object-fetch-fix:
fetch-object: set exact_oid when fetching
fetch-object: unify fetch_object[s] functions
fetch_objects() currently does not set exact_oid in struct ref when
invoking transport_fetch_refs(). If the server supports ref-in-want,
fetch_pack() uses this field to determine whether a wanted ref should be
requested as a "want-ref" line or a "want" line; without the setting of
exact_oid, the wrong line will be sent.
Set exact_oid, so that the correct line is sent.
Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The commit-graph feature is tested in isolation by
t5318-commit-graph.sh and t6600-test-reach.sh, but there are many
more interesting scenarios involving commit walks. Many of these
scenarios are covered by the existing test suite, but we need to
maintain coverage when the optional commit-graph structure is not
present.
To allow running the full test suite with the commit-graph present,
add a new test environment variable, GIT_TEST_COMMIT_GRAPH. Similar
to GIT_TEST_SPLIT_INDEX, this variable makes every Git command try
to load the commit-graph when parsing commits, and writes the
commit-graph file after every 'git commit' command.
There are a few tests that rely on commits not existing in
pack-files to trigger important events, so manually set
GIT_TEST_COMMIT_GRAPH to false for the necessary commands.
There is one test in t6024-recursive-merge.sh that relies on the
merge-base algorithm picking one of two ambiguous merge-bases, and
the commit-graph feature changes which merge-base is picked.
Helped-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Currently, repack does not touch promisor packfiles at all, potentially
causing the performance of repositories that have many such packfiles to
drop. Therefore, repack all promisor objects if invoked with -a or -A.
This is done by an additional invocation of pack-objects on all promisor
objects individually given, which takes care of deduplication and allows
the resulting packfiles to respect flags such as --max-pack-size.
Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In partial_clone_get_default_filter_spec(), the
core_partial_clone_filter_default variable may be NULL; ensure that it
is not NULL before using it.
Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Teach gc to stop traversal at promisor objects, and to leave promisor
packfiles alone. This has the effect of only repacking non-promisor
packfiles, and preserves the distinction between promisor packfiles and
non-promisor packfiles.
Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Teach rev-list to support termination of an object traversal at any
object from a promisor remote (whether one that the local repo also has,
or one that the local repo knows about because it has another promisor
object that references it).
This will be used subsequently in gc and in the connectivity check used
by fetch.
For efficiency, if an object is referenced by a promisor object, and is
in the local repo only as a non-promisor object, object traversal will
not stop there. This is to avoid building the list of promisor object
references.
(In list-objects.c, the case where obj is NULL in process_blob() and
process_tree() do not need to be changed because those happen only when
there is a conflict between the expected type and the existing object.
If the object doesn't exist, an object will be synthesized, which is
fine.)
Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Teach sha1_file to fetch objects from the remote configured in
extensions.partialclone whenever an object is requested but missing.
The fetching of objects can be suppressed through a global variable.
This is used by fsck and index-pack.
However, by default, such fetching is not suppressed. This is meant as a
temporary measure to ensure that all Git commands work in such a
situation. Future patches will update some commands to either tolerate
missing objects (without fetching them) or be more efficient in fetching
them.
In order to determine the code changes in sha1_file.c necessary, I
investigated the following:
(1) functions in sha1_file.c that take in a hash, without the user
regarding how the object is stored (loose or packed)
(2) functions in packfile.c (because I need to check callers that know
about the loose/packed distinction and operate on both differently,
and ensure that they can handle the concept of objects that are
neither loose nor packed)
(1) is handled by the modification to sha1_object_info_extended().
For (2), I looked at for_each_packed_object and others. For
for_each_packed_object, the callers either already work or are fixed in
this patch:
- reachable - only to find recent objects
- builtin/fsck - already knows about missing objects
- builtin/cat-file - warning message added in this commit
Callers of the other functions do not need to be changed:
- parse_pack_index
- http - indirectly from http_get_info_packs
- find_pack_entry_one
- this searches a single pack that is provided as an argument; the
caller already knows (through other means) that the sought object
is in a specific pack
- find_sha1_pack
- fast-import - appears to be an optimization to not store a file if
it is already in a pack
- http-walker - to search through a struct alt_base
- http-push - to search through remote packs
- has_sha1_pack
- builtin/fsck - already knows about promisor objects
- builtin/count-objects - informational purposes only (check if loose
object is also packed)
- builtin/prune-packed - check if object to be pruned is packed (if
not, don't prune it)
- revision - used to exclude packed objects if requested by user
- diff - just for optimization
Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Teach fsck to not treat missing promisor objects provided on the CLI as
an error when extensions.partialclone is set.
Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Teach fsck to not treat missing promisor objects indirectly pointed to
by refs as an error when extensions.partialclone is set.
Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Teach fsck to not treat refs referring to missing promisor objects as an
error when extensions.partialclone is set.
For the purposes of warning about no default refs, such refs are still
treated as legitimate refs.
Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Currently, Git does not support repos with very large numbers of objects
or repos that wish to minimize manipulation of certain blobs (for
example, because they are very large) very well, even if the user
operates mostly on part of the repo, because Git is designed on the
assumption that every referenced object is available somewhere in the
repo storage. In such an arrangement, the full set of objects is usually
available in remote storage, ready to be lazily downloaded.
Teach fsck about the new state of affairs. In this commit, teach fsck
that missing promisor objects referenced from the reflog are not an
error case; in future commits, fsck will be taught about other cases.
Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Jonathan Tan
brian m. carlson
Jonathan Nieder
Xin Li
Junio C Hamano
Emily Shaffer
Derrick Stolee
SZEDER Gábor
Christian Couder
Matthew DeVore