Abhishek Kumar [Sat, 16 Jan 2021 18:11:08 +0000 (18:11 +0000)]
commit-graph: fix regression when computing Bloom filters
Before computing Bloom filters, the commit-graph machinery uses
commit_gen_cmp to sort commits by generation order for improved diff
performance. 3d11275505 (commit-graph: examine commits by generation
number, 2020-03-30) claims that this sort can reduce the time spent to
compute Bloom filters by nearly half.
But since c49c82aa4c (commit: move members graph_pos, generation to a
slab, 2020-06-17), this optimization is broken, since asking for a
'commit_graph_generation()' directly returns GENERATION_NUMBER_INFINITY
while writing.
Not all hope is lost, though: 'commit_gen_cmp()' falls back to
comparing commits by their date when they have equal generation number,
and so since c49c82aa4c is purely a date comparison function. This
heuristic is good enough that we don't seem to loose appreciable
performance while computing Bloom filters.
Applying this patch (compared with v2.30.0) speeds up computing Bloom
filters by factors ranging from 0.40% to 5.19% on various repositories [1].
So, avoid the useless 'commit_graph_generation()' while writing by
instead accessing the slab directly. This returns the newly-computed
generation numbers, and allows us to avoid the heuristic by directly
comparing generation numbers.
Derrick Stolee [Thu, 7 Jan 2021 16:32:11 +0000 (16:32 +0000)]
cache-tree: speed up consecutive path comparisons
The previous change reduced time spent in strlen() while comparing
consecutive paths in verify_cache(), but we can do better. The
conditional checks the existence of a directory separator at the correct
location, but only after doing a string comparison. Swap the order to be
logically equivalent but perform fewer string comparisons.
To test the effect on performance, I used a repository with over three
million paths in the index. I then ran the following command on repeat:
Derrick Stolee [Thu, 7 Jan 2021 16:32:09 +0000 (16:32 +0000)]
index-format: discuss recursion of cache-tree better
The end of the cache tree index extension format trails off with
ellipses ever since 23fcc98 (doc: technical details about the index
file format, 2011-03-01). While an intuitive reader could gather what
this means, it could be better to use "and so on" instead.
Really, this is only justified because I also wanted to point out that
the number of subtrees in the index format is used to determine when the
recursive depth-first-search stack should be "popped." This should help
to add clarity to the format.
Signed-off-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Derrick Stolee [Thu, 7 Jan 2021 16:32:08 +0000 (16:32 +0000)]
index-format: update preamble to cache tree extension
I had difficulty in my efforts to learn about the cache tree extension
based on the documentation and code because I had an incorrect
assumption about how it behaved. This might be due to some ambiguity in
the documentation, so this change modifies the beginning of the cache
tree format by expanding the description of the feature.
My hope is that this documentation clarifies a few things:
1. There is an in-memory recursive tree structure that is constructed
from the extension data. This structure has a few differences, such
as where the name is stored.
2. What does it mean for an entry to be invalid?
3. When exactly are "new" trees created?
Helped-by: Junio C Hamano <gitster@pobox.com> Signed-off-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Derrick Stolee [Thu, 7 Jan 2021 16:32:07 +0000 (16:32 +0000)]
index-format: use 'cache tree' over 'cached tree'
The index has a "cache tree" extension. This corresponds to a
significant API implemented in cache-tree.[ch]. However, there are a few
places that refer to this erroneously as "cached tree". These are rare,
but notably the index-format.txt file itself makes this error.
The only other reference is in t7104-reset-hard.sh.
Reported-by: Junio C Hamano <gitster@pobox.com> Signed-off-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Derrick Stolee [Mon, 4 Jan 2021 03:09:14 +0000 (03:09 +0000)]
cache-tree: trace regions for prime_cache_tree
Commands such as "git reset --hard" rebuild the in-memory representation
of the cache tree index extension by parsing tree objects starting at a
known root tree. The performance of this operation can vary widely
depending on the width and depth of the repository's working directory
structure. Measure the time in this operation using trace2 regions in
prime_cache_tree().
Signed-off-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Derrick Stolee [Mon, 4 Jan 2021 03:09:13 +0000 (03:09 +0000)]
cache-tree: trace regions for I/O
As we write or read the cache tree index extension, it can be good to
isolate how much of the file I/O time is spent constructing this
in-memory tree from the existing index or writing it out again to the
new index file. Use trace2 regions to indicate that we are spending time
on this operation.
Signed-off-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Junio C Hamano [Sat, 16 Jan 2021 05:48:45 +0000 (21:48 -0800)]
Merge branch 'mt/t4129-with-setgid-dir'
Some tests expect that "ls -l" output has either '-' or 'x' for
group executable bit, but setgid bit can be inherited from parent
directory and make these fields 'S' or 's' instead, causing test
failures.
* mt/t4129-with-setgid-dir:
t4129: don't fail if setgid is set in the test directory
Junio C Hamano [Sat, 16 Jan 2021 05:48:45 +0000 (21:48 -0800)]
Merge branch 'ds/maintenance-part-4'
Follow-up on the "maintenance part-3" which introduced scheduled
maintenance tasks to support platforms whose native scheduling
methods are not 'cron'.
* ds/maintenance-part-4:
maintenance: use Windows scheduled tasks
maintenance: use launchctl on macOS
maintenance: include 'cron' details in docs
maintenance: extract platform-specific scheduling
Junio C Hamano [Fri, 15 Jan 2021 23:20:29 +0000 (15:20 -0800)]
Merge branch 'ma/sha1-is-a-hash'
Retire more names with "sha1" in it.
* ma/sha1-is-a-hash:
hash-lookup: rename from sha1-lookup
sha1-lookup: rename `sha1_pos()` as `hash_pos()`
object-file.c: rename from sha1-file.c
object-name.c: rename from sha1-name.c
Junio C Hamano [Fri, 15 Jan 2021 23:20:28 +0000 (15:20 -0800)]
Merge branch 'ma/t1300-cleanup'
Code clean-up.
* ma/t1300-cleanup:
t1300: don't needlessly work with `core.foo` configs
t1300: remove duplicate test for `--file no-such-file`
t1300: remove duplicate test for `--file ../foo`
Junio C Hamano [Fri, 15 Jan 2021 23:20:28 +0000 (15:20 -0800)]
Merge branch 'bc/rev-parse-path-format'
"git rev-parse" can be explicitly told to give output as absolute
or relative path with the `--path-format=(absolute|relative)` option.
* bc/rev-parse-path-format:
rev-parse: add option for absolute or relative path formatting
abspath: add a function to resolve paths with missing components
config: allow specifying config entries via envvar pairs
While we currently have the `GIT_CONFIG_PARAMETERS` environment variable
which can be used to pass runtime configuration data to git processes,
it's an internal implementation detail and not supposed to be used by
end users.
Next to being for internal use only, this way of passing config entries
has a major downside: the config keys need to be parsed as they contain
both key and value in a single variable. As such, it is left to the user
to escape any potentially harmful characters in the value, which is
quite hard to do if values are controlled by a third party.
This commit thus adds a new way of adding config entries via the
environment which gets rid of this shortcoming. If the user passes the
`GIT_CONFIG_COUNT=$n` environment variable, Git will parse environment
variable pairs `GIT_CONFIG_KEY_$i` and `GIT_CONFIG_VALUE_$i` for each
`i` in `[0,n)`.
While the same can be achieved with `git -c <name>=<value>`, one may
wish to not do so for potentially sensitive information. E.g. if one
wants to set `http.extraHeader` to contain an authentication token,
doing so via `-c` would trivially leak those credentials via e.g. ps(1),
which typically also shows command arguments.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
environment: make `getenv_safe()` a public function
The `getenv_safe()` helper function helps to safely retrieve multiple
environment values without the need to depend on platform-specific
behaviour for the return value's lifetime. We'll make use of this
function in a following patch, so let's make it available by making it
non-static and adding a declaration.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
config: store "git -c" variables using more robust format
The previous commit added a new format for $GIT_CONFIG_PARAMETERS which
is able to robustly handle subsections with "=" in them. Let's start
writing the new format. Unfortunately, this does much less than you'd
hope, because "git -c" itself has the same ambiguity problem! But it's
still worth doing:
- we've now pushed the problem from the inter-process communication
into the "-c" command-line parser. This would free us up to later
add an unambiguous format there (e.g., separate arguments like "git
--config key value", etc).
- for --config-env, the parser already disallows "=" in the
environment variable name. So:
git --config-env section.with=equals.key=ENVVAR
will robustly set section.with=equals.key to the contents of
$ENVVAR.
The new test shows the improvement for --config-env.
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Jeff King [Tue, 12 Jan 2021 12:27:06 +0000 (13:27 +0100)]
config: parse more robust format in GIT_CONFIG_PARAMETERS
When we stuff config options into GIT_CONFIG_PARAMETERS, we shell-quote
each one as a single unit, like:
'section.one=value1' 'section.two=value2'
On the reading side, we de-quote to get the individual strings, and then
parse them by splitting on the first "=" we find. This format is
ambiguous, because an "=" may appear in a subsection. So the config
represented in a file by both:
[section "subsection=with=equals"]
key = value
and:
[section]
subsection = with=equals.key=value
ends up in this flattened format like:
'section.subsection=with=equals.key=value'
and we can't tell which was desired. We have traditionally resolved this
by taking the first "=" we see starting from the left, meaning that we
allowed arbitrary content in the value, but not in the subsection.
Let's make our environment format a bit more robust by separately
quoting the key and value. That turns those examples into:
'section.subsection=with=equals.key'='value'
and:
'section.subsection'='with=equals.key=value'
respectively, and we can tell the difference between them. We can detect
which format is in use for any given element of the list based on the
presence of the unquoted "=". That means we can continue to allow the
old format to work to support any callers which manually used the old
format, and we can even intermingle the two formats. The old format
wasn't documented, and nobody was supposed to be using it. But it's
likely that such callers exist in the wild, so it's nice if we can avoid
breaking them. Likewise, it may be possible to trigger an older version
of "git -c" that runs a script that calls into a newer version of "git
-c"; that new version would see the intermingled format.
This does create one complication, which is that the obvious format in
the new scheme for
[section]
some-bool
is:
'section.some-bool'
with no equals. We'd mistake that for an old-style variable. And it even
has the same meaning in the old style, but:
[section "with=equals"]
some-bool
does not. It would be:
'section.with=equals=some-bool'
which we'd take to mean:
[section]
with = equals=some-bool
in the old, ambiguous style. Likewise, we can't use:
'section.some-bool'=''
because that's ambiguous with an actual empty string. Instead, we'll
again use the shell-quoting to give us a hint, and use:
'section.some-bool'=
to show that we have no value.
Note that this commit just expands the reading side. We'll start writing
the new format via "git -c" in a future patch. In the meantime, the
existing "git -c" tests will make sure we didn't break reading the old
format. But we'll also add some explicit coverage of the two formats to
make sure we continue to handle the old one after we move the writing
side over.
And one final note: since we're now using the shell-quoting as a
semantically meaningful hint, this closes the door to us ever allowing
arbitrary shell quoting, like:
'a'shell'would'be'ok'with'this'.key=value
But we have never supported that (only what sq_quote() would produce),
and we are probably better off keeping things simple, robust, and
backwards-compatible, than trying to make it easier for humans. We'll
continue not to advertise the format of the variable to users, and
instead keep "git -c" as the recommended mechanism for setting config
(even if we are trying to be kind not to break users who may be relying
on the current undocumented format).
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Junio C Hamano [Thu, 14 Jan 2021 20:21:55 +0000 (12:21 -0800)]
t4203: make blame output massaging more robust
In the "git blame --porcelain" output, lines that ends with three
integers may not be the line that shows a commit object with line
numbers and block length (the contents from the blamed file or the
summary field can have a line that happens to match). Also, the
names of the author may have more than three SP separated tokens
("git blame -L242,+1 cf6de18aabf7 Documentation/SubmittingPatches"
gives an example). The existing "grep -E | cut" pipeline is a bit
too loose on these two points.
While they can be assumed on the test data, it is not so hard to
use the right pattern from the documented format, so let's do so.
Junio C Hamano [Fri, 15 Jan 2021 02:51:02 +0000 (18:51 -0800)]
ci/install-depends: attempt to fix "brew cask" stuff
We run "git pull" against "$cask_repo"; clarify that we are
expecting not to have any of our own modifications and running "git
pull" to merely update, by passing "--ff-only" on the command line.
Also, the "brew cask install" command line triggers an error message
that says:
Error: Calling brew cask install is disabled! Use brew install
[--cask] instead.
In addition, "brew install caskroom/cask/perforce" step triggers an
error that says:
Error: caskroom/cask was moved. Tap homebrew/cask instead.
Attempt to see if blindly following the suggestion in these error
messages gets us into a better shape.
Jeff King [Thu, 14 Jan 2021 20:11:10 +0000 (15:11 -0500)]
for_each_object_in_pack(): clarify pack vs index ordering
We may return objects in one of two orders: how they appear in the .idx
(sorted by object id) or how they appear in the packfile itself. To
further complicate matters, we have two ordering variables, "i" and
"pos", and it is not clear to which order they apply.
Let's clarify this by using an unambiguous name where possible, and
leaving a comment for the variable that does double-duty.
Signed-off-by: Jeff King <peff@peff.net> Acked-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Denton Liu [Thu, 14 Jan 2021 23:02:41 +0000 (15:02 -0800)]
t4203: stop losing return codes of git commands
In a pipe, only the return code of the last command is used. Thus, all
other commands will have their return codes masked. Rewrite pipes so
that there are no git commands upstream so that their failure is
reported.
Signed-off-by: Denton Liu <liu.denton@gmail.com> Acked-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Denton Liu [Thu, 14 Jan 2021 23:02:40 +0000 (15:02 -0800)]
test-lib-functions.sh: fix usage for test_commit()
The usage comment for test_commit() shows that the --author option
should be given as `--author=<author>`. However, this is incorrect as it
only works when given as `--author <author>`. Correct this erroneous
text.
Also, for the sake of correctness, fix the description as well since we
invoke `git commit` with `--author <author>`, not `--author=<author>`.
Signed-off-by: Denton Liu <liu.denton@gmail.com> Acked-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Christian Couder [Thu, 14 Jan 2021 15:50:16 +0000 (16:50 +0100)]
pack-write: die on error in write_promisor_file()
write_promisor_file() already uses xfopen(), so it would die
if the file cannot be opened for writing. To be consistent
with this behavior and not overlook issues, let's also die if
there are errors when we are actually writing to the file.
Suggested-by: Jeff King <peff@peff.net> Suggested-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Christian Couder <chriscool@tuxfamily.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Junio C Hamano [Thu, 14 Jan 2021 20:41:54 +0000 (12:41 -0800)]
Merge branch 'en/ort-conflict-handling' into en/merge-ort-perf
* en/ort-conflict-handling:
merge-ort: add handling for different types of files at same path
merge-ort: copy find_first_merges() implementation from merge-recursive.c
merge-ort: implement format_commit()
merge-ort: copy and adapt merge_submodule() from merge-recursive.c
merge-ort: copy and adapt merge_3way() from merge-recursive.c
merge-ort: flesh out implementation of handle_content_merge()
merge-ort: handle book-keeping around two- and three-way content merge
merge-ort: implement unique_path() helper
merge-ort: handle directory/file conflicts that remain
merge-ort: handle D/F conflict where directory disappears due to merge
Junio C Hamano [Thu, 14 Jan 2021 20:41:45 +0000 (12:41 -0800)]
Merge branch 'en/diffcore-rename' into en/merge-ort-perf
* en/diffcore-rename:
diffcore-rename: remove unnecessary duplicate entry checks
diffcore-rename: accelerate rename_dst setup
diffcore-rename: simplify and accelerate register_rename_src()
t4058: explore duplicate tree entry handling in a bit more detail
t4058: add more tests and documentation for duplicate tree entry handling
diffcore-rename: reduce jumpiness in progress counters
diffcore-rename: simplify limit check
diffcore-rename: avoid usage of global in too_many_rename_candidates()
diffcore-rename: rename num_create to num_destinations
Taylor Blau [Wed, 13 Jan 2021 22:25:10 +0000 (17:25 -0500)]
pack-revindex.c: avoid direct revindex access in 'offset_to_pack_pos()'
To prepare for on-disk reverse indexes, remove a spot in
'offset_to_pack_pos()' that looks at the 'revindex' array in 'struct
packed_git'.
Even though this use of the revindex pointer is within pack-revindex.c,
this clean up is still worth doing. Since the 'revindex' pointer will be
NULL when reading from an on-disk reverse index (instead the
'revindex_data' pointer will be mmaped to the 'pack-*.rev' file), this
call-site would have to include a conditional to lookup the offset for
position 'mi' each iteration through the search.
So instead of open-coding 'pack_pos_to_offset()', call it directly from
within 'offset_to_pack_pos()'.
Signed-off-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Taylor Blau [Wed, 13 Jan 2021 22:25:06 +0000 (17:25 -0500)]
pack-revindex: hide the definition of 'revindex_entry'
Now that all spots outside of pack-revindex.c that reference 'struct
revindex_entry' directly have been removed, it is safe to hide the
implementation by moving it from pack-revindex.h to pack-revindex.c.
Signed-off-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Now that all 'find_revindex_position()' callers have been removed (and
converted to the more descriptive 'offset_to_pack_pos()'), it is almost
safe to get rid of 'find_revindex_position()' entirely. Almost, except
for the fact that 'offset_to_pack_pos()' calls
'find_revindex_position()'.
Inline 'find_revindex_position()' into 'offset_to_pack_pos()', and
then remove 'find_revindex_position()' entirely.
This is a straightforward refactoring with one minor snag.
'offset_to_pack_pos()' used to load the index before calling
'find_revindex_position()'. That means that by the time
'find_revindex_position()' starts executing, 'p->num_objects' can be
safely read. After inlining, be careful to not read 'p->num_objects'
until _after_ 'load_pack_revindex()' (which loads the index as a
side-effect) has been called.
Another small fix that is included is converting the upper- and
lower-bounds to be unsigned's instead of ints. This dates back to 92e5c77c37 (revindex: export new APIs, 2013-10-24)--ironically, the last
time we introduced new APIs here--but this unifies the types.
Signed-off-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Taylor Blau [Wed, 13 Jan 2021 22:24:54 +0000 (17:24 -0500)]
builtin/gc.c: guess the size of the revindex
'estimate_repack_memory()' takes into account the amount of memory
required to load the reverse index in memory by multiplying the assumed
number of objects by the size of the 'revindex_entry' struct.
Prepare for hiding the definition of 'struct revindex_entry' by removing
a 'sizeof()' of that type from outside of pack-revindex.c. Instead,
guess that one off_t and one uint32_t are required per object. Strictly
speaking, this is a worse guess than asking for 'sizeof(struct
revindex_entry)' directly, since the true size of this struct is 16
bytes with padding on the end of the struct in order to align the offset
field.
But, this is an approximation anyway, and it does remove a use of the
'struct revindex_entry' from outside of pack-revindex internals.
Signed-off-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Taylor Blau [Wed, 13 Jan 2021 22:24:45 +0000 (17:24 -0500)]
unpack_entry(): convert to new revindex API
Remove direct manipulation of the 'struct revindex_entry' type as well
as calls to the deprecated API in 'packfile.c:unpack_entry()'. Usual
clean-up is performed (replacing '->nr' with calls to
'pack_pos_to_index()' and so on).
Add an additional check to make sure that 'obj_offset()' points at a
valid object. In the case this check is violated, we cannot call
'mark_bad_packed_object()' because we don't know the OID. At the top of
the call stack is do_oid_object_info_extended() (via
packed_object_info()), which does mark the object.
Signed-off-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Taylor Blau [Wed, 13 Jan 2021 22:24:41 +0000 (17:24 -0500)]
packed_object_info(): convert to new revindex API
Convert another call of 'find_pack_revindex()' to its replacement
'pack_pos_to_offset()'. Likewise:
- Avoid manipulating `struct packed_git`'s `revindex` pointer directly
by removing the pointer-as-array indexing.
- Add an additional guard to check that the offset 'obj_offset()'
points to a real object. This should be the case with well-behaved
callers to 'packed_object_info()', but isn't guarenteed.
Other blocks that fill in various other values from the 'struct
object_info' request handle bad inputs by setting the type to
'OBJ_BAD' and jumping to 'out'. Do the same when given a bad offset
here.
The previous code would have segfaulted when given a bad
'obj_offset' value, since 'find_pack_revindex()' would return
'NULL', and then the line that fills 'oi->disk_sizep' would try to
access 'NULL[1]' with a stride of 16 bytes (the width of 'struct
revindex_entry)'.
Signed-off-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Taylor Blau [Wed, 13 Jan 2021 22:24:27 +0000 (17:24 -0500)]
rebuild_existing_bitmaps(): convert to new revindex API
Remove another instance of looking at the revindex directly by instead
calling 'pack_pos_to_index()'. Unlike other patches, this caller only
cares about the index position of each object in the loop.
Signed-off-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Taylor Blau [Wed, 13 Jan 2021 22:24:05 +0000 (17:24 -0500)]
try_partial_reuse(): convert to new revindex API
Remove another instance of direct revindex manipulation by calling
'pack_pos_to_offset()' instead (the caller here does not care about the
index position of the object at position 'pos').
Note that we cannot just use the existing "offset" variable to store the
value we get from pack_pos_to_offset(). It is incremented by
unpack_object_header(), but we later need the original value. Since
we'll no longer have revindex->offset to read it from, we'll store that
in a separate variable ("header" since it points to the entry's header
bytes).
Signed-off-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Taylor Blau [Wed, 13 Jan 2021 22:24:00 +0000 (17:24 -0500)]
get_size_by_pos(): convert to new revindex API
Remove another caller that holds onto a 'struct revindex_entry' by
replacing the direct indexing with calls to 'pack_pos_to_offset()' and
'pack_pos_to_index()'.
Signed-off-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Taylor Blau [Wed, 13 Jan 2021 22:23:56 +0000 (17:23 -0500)]
show_objects_for_type(): convert to new revindex API
Avoid storing the revindex entry directly, since this structure will
soon be removed from the public interface. Instead, store the offset and
index position by calling 'pack_pos_to_offset()' and
'pack_pos_to_index()', respectively.
Signed-off-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Taylor Blau [Wed, 13 Jan 2021 22:23:47 +0000 (17:23 -0500)]
check_object(): convert to new revindex API
Replace direct accesses to the revindex with calls to
'offset_to_pack_pos()' and 'pack_pos_to_index()'.
Since this caller already had some error checking (it can jump to the
'give_up' label if it encounters an error), we can easily check whether
or not the provided offset points to an object in the given pack. This
error checking existed prior to this patch, too, since the caller checks
whether the return value from 'find_pack_revindex()' was NULL or not.
Signed-off-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Taylor Blau [Wed, 13 Jan 2021 22:23:35 +0000 (17:23 -0500)]
write_reuse_object(): convert to new revindex API
First replace 'find_pack_revindex()' with its replacement
'offset_to_pack_pos()'. This prevents any bogus OFS_DELTA that may make
its way through until 'write_reuse_object()' from causing a bad memory
read (if 'revidx' is 'NULL')
Next, replace a direct access of '->nr' with the wrapper function
'pack_pos_to_index()'.
Signed-off-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Taylor Blau [Wed, 13 Jan 2021 22:23:31 +0000 (17:23 -0500)]
pack-revindex: introduce a new API
In the next several patches, we will prepare for loading a reverse index
either in memory (mapping the inverse of the .idx's contents in-core),
or directly from a yet-to-be-introduced on-disk format. To prepare for
that, we'll introduce an API that avoids the caller explicitly indexing
the revindex pointer in the packed_git structure.
There are four ways to interact with the reverse index. Accordingly,
four functions will be exported from 'pack-revindex.h' by the time that
the existing API is removed. A caller may:
1. Load the pack's reverse index. This involves opening up the index,
generating an array, and then sorting it. Since opening the index
can fail, this function ('load_pack_revindex()') returns an int.
Accordingly, it takes only a single argument: the 'struct
packed_git' the caller wants to build a reverse index for.
This function is well-suited for both the current and new API.
Callers will have to continue to open the reverse index explicitly,
but this function will eventually learn how to detect and load a
reverse index from the on-disk format, if one exists. Otherwise, it
will fallback to generating one in memory from scratch.
2. Convert a pack position into an offset. This operation is now
called `pack_pos_to_offset()`. It takes a pack and a position, and
returns the corresponding off_t.
Any error simply calls BUG(), since the callers are not well-suited
to handle a failure and keep going.
3. Convert a pack position into an index position. Same as above; this
takes a pack and a position, and returns a uint32_t. This operation
is known as `pack_pos_to_index()`. The same thinking about error
conditions applies here as well.
4. Find the pack position for a given offset. This operation is now
known as `offset_to_pack_pos()`. It takes a pack, an offset, and a
pointer to a uint32_t where the position is written, if an object
exists at that offset. Otherwise, -1 is returned to indicate
failure.
Unlike some of the callers that used to access '->offset' and '->nr'
directly, the error checking around this call is somewhat more
robust. This is important since callers should always pass an offset
which points at the boundary of two objects. The API, unlike direct
access, enforces that that is the case.
This will become important in a subsequent patch where a caller
which does not but could check the return value treats the signed
`-1` from `find_revindex_position()` as an index into the 'revindex'
array.
Two design warts are carried over into the new API:
- Asking for the index position of an out-of-bounds object will result
in a BUG() (since no such object exists), but asking for the offset
of the non-existent object at the end of the pack returns the total
size of the pack.
This makes it convenient for callers who always want to take the
difference of two adjacent object's offsets (to compute the on-disk
size) but don't want to worry about boundaries at the end of the
pack.
- offset_to_pack_pos() lazily loads the reverse index, but
pack_pos_to_index() doesn't (callers of the former are well-suited
to handle errors, but callers of the latter are not).
Signed-off-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Update the CoC added in 5cdf2301 (add a Code of Conduct document,
2019-09-24 from version 1.4 to version 2.0. This is the version found
at [1] with the following minor changes:
- We preserve the change to the CoC in 3f9ef874a73 (CODE_OF_CONDUCT:
mention individual project-leader emails, 2019-09-26)
- We preserve the custom intro added in 5cdf2301d4a (add a Code of
Conduct document, 2019-09-24)
This change intentionally preserves a warning emitted on "git diff
--check". It's better to make it easily diff-able with upstream than
to fix whitespace changes in our version while we're at it.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Acked-by: Christian Couder <chriscool@tuxfamily.org> Acked-by: Derrick Stolee <dstolee@microsoft.com> Acked-by: Elijah Newren <newren@gmail.com> Acked-by: Johannes Schindelin <johannes.schindelin@gmx.de> Acked-by: Jonathan Nieder <jrnieder@gmail.com> Acked-by: brian m. carlson <sandals@crustytoothpaste.net> Acked-by: Jeff King <peff@peff.net> Acked-by: Taylor Blau <me@ttaylor.com> Acked-by: Jonathan Tan <jonathantanmy@google.com> Acked-by: Junio C Hamano <gitster@pobox.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Christian Couder [Tue, 12 Jan 2021 08:21:59 +0000 (09:21 +0100)]
fetch-pack: refactor writing promisor file
Let's replace the 2 different pieces of code that write a
promisor file in 'builtin/repack.c' and 'fetch-pack.c'
with a new function called 'write_promisor_file()' in
'pack-write.c' and 'pack.h'.
This might also help us in the future, if we want to put
back the ref names and associated hashes that were in
the promisor files we are repacking in 'builtin/repack.c'
as suggested by a NEEDSWORK comment just above the code
we are refactoring.
Signed-off-by: Christian Couder <chriscool@tuxfamily.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Christian Couder [Tue, 12 Jan 2021 08:21:58 +0000 (09:21 +0100)]
fetch-pack: rename helper to create_promisor_file()
As we are going to refactor the code that actually writes
the promisor file into a separate function in a following
commit, let's rename the current write_promisor_file()
function to create_promisor_file().
Signed-off-by: Christian Couder <chriscool@tuxfamily.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Remove support for the magical "repo-abbrev" comment in .mailmap
files. This was added to .mailmap parsing in [1], as a generalized
feature of the git-shortlog Perl script added earlier in [2].
There was no documentation or tests for this feature, and I don't
think it's used in practice anymore.
What it did was to allow you to specify a single string to be
search-replaced with "/.../" in the .mailmap file. E.g. for
linux.git's current .mailmap:
git archive --remote=git@gitlab.com:linux-kernel/linux.git \
HEAD -- .mailmap | grep -a repo-abbrev
# repo-abbrev: /pub/scm/linux/kernel/git/
Merge tag [...]git.kernel.org/pub/scm/linux/kernel/git/tip/tip
I think at this point this is just a historical artifact we can get
rid of. It was initially meant for Linus's own use when we integrated
the Perl script[2], but since then it seems he's stopped using it.
Digging through Linus's release announcements on the LKML[3] the last
release I can find that made use of this output is Linux 2.6.25-rc6
back in March 2008[4]. Later on Linus started using --no-merges[5],
and nowadays seems to prefer some custom not-quite-shortlog format of
merges from lieutenants[6].
You will still see it on linux.git if you run "git shortlog" manually
yourself with --merges, with this removed you can still get the same
output with:
git log --pretty=fuller v5.10-rc7..v5.10 |
sed 's!/pub/scm/linux/kernel/git/!/.../!g' |
git shortlog
Arguably we should do the same for the search-replacing of "[PATCH]"
at the beginning with "". That seems to be another relic of a bygone
era when linux.git patches would have their E-Mail subject lines
applied as-is by "git am" or whatever. But we documented that feature
in "git-shortlog(1)", and it seems more widely applicable than
something purely kernel-specific.
1. 7595e2ee6ef (git-shortlog: make common repository prefix
configurable with .mailmap, 2006-11-25)
2. fa375c7f1b6 (Add git-shortlog perl script, 2005-06-04)
3. https://lore.kernel.org/lkml/
4. https://lore.kernel.org/lkml/alpine.LFD.1.00.0803161651350.3020@woody.linux-foundation.org/
5. https://lore.kernel.org/lkml/BANLkTinrbh7Xi27an3uY7pDWrNKhJRYmEA@mail.gmail.com/
6. https://lore.kernel.org/lkml/CAHk-=wg1+kf1AVzXA-RQX0zjM6t9J2Kay9xyuNqcFHWV-y5ZYw@mail.gmail.com/
Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
mailmap doc + tests: document and test for case-insensitivity
Add documentation and more tests for case-insensitivity. The existing
test only matched on the E-Mail part, but as shown here we also match
the name with strcasecmp().
This behavior was last discussed on the mailing list in the thread
starting at [1]. It seems we're keeping it like this, so let's
document it.
Reported-by: Martin Ågren <martin.agren@gmail.com> Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
mailmap doc + tests: add better examples & test them
Change the mailmap documentation added in 0925ce4d49 (Add map_user()
and clear_mailmap() to mailmap, 2009-02-08) to continue discussing the
Jane/Joe example. I think this makes things a lot less confusing as
we're building up more complex examples using one set of data which
covers all the things we'd like to discuss.
Also add tests to assert that what our documentation says is what's
actually happening. This is mostly (or entirely) covered by existing
tests which I'm not deleting, but having these tests for the synopsis
makes it easier to follow-along while reading the tests & docs.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
tests: refactor a few tests to use "test_commit --append"
Refactor a few more tests to use the new "--append" option to
"test_commit". I added it for use in the mailmap tests, but this
demonstrates how useful it is in general.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
test-lib functions: add an --append option to test_commit
Add an --append option to test_commit to append <contents> to the
<file> we're writing to. This simplifies a lot of test setup, as shown
in some of the tests being changed here.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
test-lib functions: add --author support to test_commit
Add support for --author to "test_commit". This will simplify some
current and future tests, one of those is being changed here.
Let's also line-wrap the "git commit" command invocation to make diffs
that add subsequent options easier to add, as they'll only need to add
a new option line.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
test-lib functions: document arguments to test_commit
The --notick argument was added in [1] and was followed by --signoff
in [2], but neither of these commits added any documentation for these
options. When -C was added in [3] a comment was added to document it,
but not the other options. Let's document all of these options.
1. 44b85e89d7 (t7003: add test to filter a branch with a commit at
epoch, 2012-07-12),
2. 5ed75e2a3f (cherry-pick: don't forget -s on failure, 2012-09-14).
3. 6f94351b0a (test-lib-functions.sh: teach test_commit -C <dir>,
2016-12-08)
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Expand the comment template for "test_commit" to match that of
"test_commit_bulk" added in b1c36cb849 (test-lib: introduce
test_commit_bulk, 2019-07-02). It has several undocumented options,
which won't all fit on one line. Follow-up commit(s) will document
them.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
mailmap: test for silent exiting on missing file/blob
That we silently ignore missing mailmap.file or mailmap.blob values is
intentional. See 938a60d64f (mailmap: clean up read_mailmap error
handling, 2012-12-12). However, nothing tested for this. Let's do that
by checking that stderr is empty in those cases.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
mailmap tests: get rid of overly complex blame fuzzing
Change a test that used a custom fuzzing function since bfdfa3d414 (t4203 (mailmap): stop hardcoding commit ids and dates,
2010-10-15) to just use the "blame --porcelain" output instead.
We could use the same pattern as 0ba9c9a0fb (t8008: rely on
rev-parse'd HEAD instead of sha1 value, 2017-07-26) does to do this,
but there wouldn't be any point. We're not trying to test "blame"
output here in general, just that "blame" pays attention to the
mailmap.
So it's sufficient to get the blamed line(s) and authors from the
output, which is much easier with the "--porcelain" option.
It would still be possible for there to be a bug in "blame" such that
it uses the mailmap for its "--porcelain" output, but not the regular
output. Let's test for that simply by checking if specifying the
mailmap changes the output.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Remove a redundant line in a test added in d20d654fe8 (Change current
mailmap usage to do matching on both name and email of
author/committer., 2009-02-08).
This didn't conceivably test anything useful and is most likely a
copy/paste error.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
The --stdin tests setup the "contact" file in the main setup, let's
instead set it up in the test that uses it.
Also refactor the first test so it's obvious that the point of it is
that "check-mailmap" will spew its input as-is when given no
argument. For that one we can just use the "expect" file as-is.
Also add tests for how other "--stdin" cases are handled, e.g. one
where we actually do a mapping.
For the rest of --stdin testing we just assume we're going to get the
same output. We could follow-up and make sure everything's
round-tripped through both --stdin and the file/blob backends, but I
don't think there's much point in that.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* Setup "actual" test files in the body of "test_expect_success"
* Don't have X of "test_expect_success X Y" be an unquoted string.
* Not to carry over test config between tests, and instead use
"test_config".
* Replace various "echo" a line-at-a-time patterns with here-docs.
* Change a case of "log.mailmap=False" to use the lower-case
"false". Both work, but this ends up in git-config's boolean
parsing and these atypical values are tested for elsewhere. Let's
use the lower-case to not draw the reader's attention to this
abnormality.
* Remove commentary asserting that things work a given way in favor
of simply testing for it, i.e. in the case of a .mailmap file
outside of the repository.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
mailmap tests: use our preferred whitespace syntax
Change these tests to use the preferred whitespace around ">",
"<<-EOF" etc. This is an initial step in larger and more meaningful
refactoring of the file, which makes a subsequent commit easier to
read.
I'm not changing the whitespace of "echo <str> > file" patterns to
"echo <str> >file" because all of those will be changed to here-docs
in a subsequent commit.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
mailmap doc: start by mentioning the comment syntax
Mentioning the comment syntax and blank line support first is in line
with how "git help config" describes its format. See b8936cf060 (config.txt grammar, typo, and asciidoc fixes, 2006-06-08)
for the paragraph I'm copying & amending from its documentation.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add a passing mention of the mailmap.file and mailmap.blob
configuration options. Before this addition a reader of the
"check-mailmap" manpage would have no idea that a custom map could be
specified, unless they'd happen to e.g. come across it in the "config"
manpage first.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Quote the mailmap.file and mailmap.blob configuration variables as
`mailmap.file` and `mailmap.blob`, and link to git-config(1). This is
in line with the preferred way of doing this in the rest of our
documentation.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
mailmap doc: create a new "gitmailmap(5)" man page
Create a gitmailmap(5) page similar to how .gitmodules and .gitignore
have their own pages at gitmodules(5) and gitignore(5). Now instead of
"check-mailmap", "blame" and "shortlog" documentation including the
description of the format we link to one canonical place.
This makes things easier for readers, since in our manpage or
web-based[1] output it's not clear that the "MAPPING AUTHORS" sections
aren't subtly different, as opposed to just included.
1. https://git-scm.com/docs/git-check-mailmap
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
fetch: implement support for atomic reference updates
When executing a fetch, then git will currently allocate one reference
transaction per reference update and directly commit it. This means that
fetches are non-atomic: even if some of the reference updates fail,
others may still succeed and modify local references.
This is fine in many scenarios, but this strategy has its downsides.
- The view of remote references may be inconsistent and may show a
bastardized state of the remote repository.
- Batching together updates may improve performance in certain
scenarios. While the impact probably isn't as pronounced with loose
references, the upcoming reftable backend may benefit as it needs to
write less files in case the update is batched.
- The reference-update hook is currently being executed twice per
updated reference. While this doesn't matter when there is no such
hook, we have seen severe performance regressions when doing a
git-fetch(1) with reference-transaction hook when the remote
repository has hundreds of thousands of references.
Similar to `git push --atomic`, this commit thus introduces atomic
fetches. Instead of allocating one reference transaction per updated
reference, it causes us to only allocate a single transaction and commit
it as soon as all updates were received. If locking of any reference
fails, then we abort the complete transaction and don't update any
reference, which gives us an all-or-nothing fetch.
Note that this may not completely fix the first of above downsides, as
the consistent view also depends on the server-side. If the server
doesn't have a consistent view of its own references during the
reference negotiation phase, then the client would get the same
inconsistent view the server has. This is a separate problem though and,
if it actually exists, can be fixed at a later point.
This commit also changes the way we write FETCH_HEAD in case `--atomic`
is passed. Instead of writing changes as we go, we need to accumulate
all changes first and only commit them at the end when we know that all
reference updates succeeded. Ideally, we'd just do so via a temporary
file so that we don't need to carry all updates in-memory. This isn't
trivially doable though considering the `--append` mode, where we do not
truncate the file but simply append to it. And given that we support
concurrent processes appending to FETCH_HEAD at the same time without
any loss of data, seeding the temporary file with current contents of
FETCH_HEAD initially and then doing a rename wouldn't work either. So
this commit implements the simple strategy of buffering all changes and
appending them to the file on commit.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
fetch: allow passing a transaction to `s_update_ref()`
The handling of ref updates is completely handled by `s_update_ref()`,
which will manage the complete lifecycle of the reference transaction.
This is fine right now given that git-fetch(1) does not support atomic
fetches, so each reference gets its own transaction. It is quite
inflexible though, as `s_update_ref()` only knows about a single
reference update at a time, so it doesn't allow us to alter the
strategy.
This commit prepares `s_update_ref()` and its only caller
`update_local_ref()` to allow passing an external transaction. If none
is given, then the existing behaviour is triggered which creates a new
transaction and directly commits it. Otherwise, if the caller provides a
transaction, then we only queue the update but don't commit it. This
optionally allows the caller to manage when a transaction will be
committed.
Given that `update_local_ref()` is always called with a `NULL`
transaction for now, no change in behaviour is expected from this
change.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
fetch: refactor `s_update_ref` to use common exit path
The cleanup code in `s_update_ref()` is currently duplicated for both
succesful and erroneous exit paths. This commit refactors the function
to have a shared exit path for both cases to remove the duplication.
Suggested-by: Christian Couder <christian.couder@gmail.com> Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit refactors `append_fetch_head()` to use a `struct strbuf` for
formatting the update which we're about to append to the FETCH_HEAD
file. While the refactoring doesn't have much of a benefit right now, it
serves as a preparatory step to implement atomic fetches where we need
to buffer all updates to FETCH_HEAD and only flush them out if all
reference updates succeeded.
No change in behaviour is expected from this commit.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
projects / rit / log