expand_user_path() was renamed to interpolate_path() back in mid-2021,
but reinstated with a #define and a NEEDSWORK comment that we would
eventually want to get rid of it. Do so now.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This is another step towards letting us remove the include of cache.h in
strbuf.c. It does mean that we also need to add includes of abspath.h
in a number of C files.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This is one step towards making strbuf.c not depend upon cache.h.
Additional steps will follow in subsequent commits.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"git bundle" learned that "-" is a common way to say that the input
comes from the standard input and/or the output goes to the
standard output. It used to work only for output and only from the
root level of the working tree.
* jk/bundle-use-dash-for-stdfiles:
parse-options: use prefix_filename_except_for_dash() helper
parse-options: consistently allocate memory in fix_filename()
bundle: don't blindly apply prefix_filename() to "-"
bundle: document handling of "-" as stdin
bundle: let "-" mean stdin for reading operations
A user can specify a filename to a command from the command line,
either as the value given to a command line option, or a command
line argument. When it is given as a relative filename, in the
user's mind, it is relative to the directory "git" was started from,
but by the time the filename is used, "git" would almost always have
chdir()'ed up to the root level of the working tree.
The given filename, if it is relative, needs to be prefixed with the
path to the current directory, and it typically is done by calling
prefix_filename() helper function. For commands that can also take
"-" to use the standard input or the standard output, however, this
needs to be done with care.
"git bundle create" uses the next word on the command line as the
output filename, and can take "-" to mean "write to the standard
output". It blindly called prefix_filename(), so running it in a
subdirectory did not quite work as expected.
Introduce a new helper, prefix_filename_except_for_dash(), and use
it to help "git bundle create" codepath.
Reported-by: Michael Henry
Helped-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Adjust several files to be more explicit about their dependency on
replace-objects to accommodate this change.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Moving a few functions around allows us to make dir.h no longer need to
include cache.h. This commit is best viewed with:
git log -1 -p --color-moved
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Things should be able to depend on object.h without pulling in all of
cache.h. Move an enum to allow this.
Note that a couple files previously depended on things brought in
through cache.h indirectly (revision.h -> commit.h -> object.h ->
cache.h). As such, this change requires making existing dependencies
more explicit in half a dozen files. The inclusion of strbuf.h in
some headers if of particular note: these headers directly embedded a
strbuf in some new structs, meaning they should have been including
strbuf.h all along but were indirectly getting the necessary
definitions.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
These functions were all defined in a separate ident.c already, so
create ident.h and move the declarations into that file.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
hex.c contains code for hex-related functions, but for some reason these
functions were declared in the catch-all cache.h. Move the function
declarations into a hex.h header instead.
This also allows us to remove includes of cache.h from a few C files.
For now, we make cache.h include hex.h, so that it is easier to review
the direct changes being made by this patch. In the next patch, we will
remove that, and add the necessary direct '#include "hex.h"' in the
hundreds of C files that need it.
Note that reviewing the header changes in this commit might be
simplified via
git log --no-walk -p --color-moved $COMMIT -- '*.h'`
In particular, it highlights the simple movement of code in .h files
rather nicely.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
These defines and enum are all oid-related and as such seem to make
more sense being included in hash.h. Further, moving them there
allows us to remove some includes of cache.h in other files.
The change to line-log.h might look unrelated, but line-log.h includes
diffcore.h, which previously included cache.h, which included the
kitchen sink. Since this patch makes diffcore.h no longer include
cache.h, the compiler complains about the 'struct string_list *'
function parameter. Add a forward declaration for struct string_list to
address this.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This allows us to replace includes of cache.h with includes of the much
smaller alloc.h in many places. It does mean that we also need to add
includes of alloc.h in a number of C files.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Have the last users of "USE_THE_INDEX_COMPATIBILITY_MACROS" use the
underlying *_index() variants instead. Now all previous users of
"USE_THE_INDEX_COMPATIBILITY_MACROS" have been migrated away from the
wrapper macros, and if applicable to use the "USE_THE_INDEX_VARIABLE"
added in [1].
Let's leave the "index-compatibility.cocci" in place, even though it
won't be doing anything on "master". It will benefit any out-of-tree
code that need to use these compatibility macros. We can eventually
remove it.
1. bdafeae0b9 (cache.h & test-tool.h: add & use
"USE_THE_INDEX_VARIABLE", 2022-11-19)
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Apply the rule added in [1] to change "cache_name_pos" to
"index_name_pos", which allows us to get rid of another
"USE_THE_INDEX_COMPATIBILITY_MACROS" macro.
The replacement of "USE_THE_INDEX_COMPATIBILITY_MACROS" here with
"USE_THE_INDEX_VARIABLE" is a manual change on top, now that these
files only use "&the_index", and don't need any compatibility
macros (or functions).
1. 0e6550a2c6 (cocci: add a index-compatibility.pending.cocci,
2022-11-19)
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Apply the "active_nr" part of "index-compatibility.pending.cocci",
which was left out in [1] due to an in-flight conflict. As of [2] the
topic we conflicted with has been merged to "master", so we can fully
apply this rule.
1. dc594180d9 (cocci & cache.h: apply variable section of "pending"
index-compatibility, 2022-11-19)
2. 9ea1378d04 (Merge branch 'ab/various-leak-fixes', 2022-12-14)
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Support names of any length in base_name_compare() and df_name_compare()
by using size_t for their length parameters. They pass the length on to
memcmp(3), which also takes it as a size_t.
Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When the "repo" member was added to "the_index" in [1] the
repo_read_index() was made to populate it, but the unpopulated
"the_index" variable didn't get the same treatment.
Let's do that in initialize_the_repository() when we set it up, and
likewise for all of the current callers initialized an empty "struct
index_state".
This simplifies code that needs to deal with "the_index" or a custom
"struct index_state", we no longer need to second-guess this part of
the "index_state" deep in the stack. A recent example of such
second-guessing is the "istate->repo ? istate->repo : the_repository"
code in [2]. We can now simply use "istate->repo".
We're doing this by making use of the INDEX_STATE_INIT() macro (and
corresponding function) added in [3], which now have mandatory "repo"
arguments.
Because we now call index_state_init() in repository.c's
initialize_the_repository() we don't need to handle the case where we
have a "repo->index" whose "repo" member doesn't match the "repo"
we're setting up, i.e. the "Complete the double-reference" code in
repo_read_index() being altered here. That logic was originally added
in [1], and was working around the lack of what we now have in
initialize_the_repository().
For "fsmonitor-settings.c" we can remove the initialization of a NULL
"r" argument to "the_repository". This was added back in [4], and was
needed at the time for callers that would pass us the "r" from an
"istate->repo". Before this change such a change to
"fsmonitor-settings.c" would segfault all over the test suite (e.g. in
t0002-gitfile.sh).
This change has wider eventual implications for
"fsmonitor-settings.c". The reason the other lazy loading behavior in
it is required (starting with "if (!r->settings.fsmonitor) ..." is
because of the previously passed "r" being "NULL".
I have other local changes on top of this which move its configuration
reading to "prepare_repo_settings()" in "repo-settings.c", as we could
now start to rely on it being called for our "r". But let's leave all
of that for now, and narrowly remove this particular part of the
lazy-loading.
1. 1fd9ae517c (repository: add repo reference to index_state,
2021-01-23)
2. ee1f0c242e (read-cache: add index.skipHash config option,
2023-01-06)
3. 2f6b1eb794 (cache API: add a "INDEX_STATE_INIT" macro/function,
add release_index(), 2023-01-12)
4. 1e0ea5c431 (fsmonitor: config settings are repository-specific,
2022-03-25)
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Acked-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Hopefully in some not so distant future, we'll get advantages from always
initializing the "repo" member of the "struct index_state". To make
that easier let's introduce an initialization macro & function.
The various ad-hoc initialization of the structure can then be changed
over to it, and we can remove the various "0" assignments in
discard_index() in favor of calling index_state_init() at the end.
While not strictly necessary, let's also change the CALLOC_ARRAY() of
various "struct index_state *" to use an ALLOC_ARRAY() followed by
index_state_init() instead.
We're then adding the release_index() function and converting some
callers (including some of these allocations) over to it if they
either won't need to use their "struct index_state" again, or are just
about to call index_state_init().
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Acked-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Stop using "git --super-prefix" and narrow the scope of its use to
the submodule--helper.
* ab/no-more-git-global-super-prefix:
read-tree: add "--super-prefix" option, eliminate global
submodule--helper: convert "{update,clone}" to their own "--super-prefix"
submodule--helper: convert "status" to its own "--super-prefix"
submodule--helper: convert "sync" to its own "--super-prefix"
submodule--helper: convert "foreach" to its own "--super-prefix"
submodule--helper: don't use global --super-prefix in "absorbgitdirs"
submodule.c & submodule--helper: pass along "super_prefix" param
read-tree + fetch tests: test failing "--super-prefix" interaction
submodule absorbgitdirs tests: add missing "Migrating git..." tests
The "--super-prefix" option to "git" was initially added in [1] for
use with "ls-files"[2], and shortly thereafter "submodule--helper"[3]
and "grep"[4]. It wasn't until [5] that "read-tree" made use of it.
At the time [5] made sense, but since then we've made "ls-files"
recurse in-process in [6], "grep" in [7], and finally
"submodule--helper" in the preceding commits.
Let's also remove it from "read-tree", which allows us to remove the
option to "git" itself.
We can do this because the only remaining user of it is the submodule
API, which will now invoke "read-tree" with its new "--super-prefix"
option. It will only do so when the "submodule_move_head()" function
is called.
That "submodule_move_head()" function was then only invoked by
"read-tree" itself, but now rather than setting an environment
variable to pass "--super-prefix" between cmd_read_tree() we:
- Set a new "super_prefix" in "struct unpack_trees_options". The
"super_prefixed()" function in "unpack-trees.c" added in [5] will now
use this, rather than get_super_prefix() looking up the environment
variable we set earlier in the same process.
- Add the same field to the "struct checkout", which is only needed to
ferry the "super_prefix" in the "struct unpack_trees_options" all the
way down to the "entry.c" callers of "submodule_move_head()".
Those calls which used the super prefix all originated in
"cmd_read_tree()". The only other caller is the "unlink_entry()"
caller in "builtin/checkout.c", which now passes a "NULL".
1. 74866d7579 (git: make super-prefix option, 2016-10-07)
2. e77aa336f1 (ls-files: optionally recurse into submodules, 2016-10-07)
3. 89c8626557 (submodule helper: support super prefix, 2016-12-08)
4. 0281e487fd (grep: optionally recurse into submodules, 2016-12-16)
5. 3d415425c7 (unpack-trees: support super-prefix option, 2017-01-17)
6. 188dce131f (ls-files: use repository object, 2017-06-22)
7. f9ee2fcdfa (grep: recurse in-process using 'struct repository', 2017-08-02)
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We take a ws_rule parameter, but have never looked at it since the
function was added in 877f23ccb8 (Teach "diff --check" about new blank
lines at end, 2008-06-26). A comment in the function does mention how we
_could_ use it, but nobody has felt the need to do so for over a decade.
We could keep it around as reminder of what could be done, but the
comment serves that purpose. And in the meantime, it triggers
-Wunused-parameter.
So let's drop it, which in turn allows us to drop similar arguments
further up the callstack. I've left the comment intact. It does still
say "ws_rule", but that name is used consistently in the whitespace
code, so the meaning is clear.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Apply "index-compatibility.pending.cocci" rule to "builtin/*", but
exclude those where we conflict with in-flight changes.
As a result some of them end up using only "the_index", so let's have
them use the more narrow "USE_THE_INDEX_VARIABLE" rather than
"USE_THE_INDEX_COMPATIBILITY_MACROS".
Manual changes not made by coccinelle, that were squashed in:
* Whitespace-wrap argument lists for repo_hold_locked_index(),
repo_read_index_preload() and repo_refresh_and_write_index(), in cases
where the line became too long after the transformation.
* Change "refresh_cache()" to "refresh_index()" in a comment in
"builtin/update-index.c".
* For those whose call was followed by perror("<macro-name>"), change
it to perror("<function-name>"), referring to the new function.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Split up the "USE_THE_INDEX_COMPATIBILITY_MACROS" into that setting
and a more narrow "USE_THE_INDEX_VARIABLE". In the case of these
built-ins we only need "the_index" variable, but not the compatibility
wrapper for functions we're not using.
Let's then have some users of "USE_THE_INDEX_COMPATIBILITY_MACROS" use
this more narrow and descriptive define.
For context: The USE_THE_INDEX_COMPATIBILITY_MACROS macro was added to
test-tool.h in f8adbec9fe (cache.h: flip
NO_THE_INDEX_COMPATIBILITY_MACROS switch, 2019-01-24).
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Mostly apply the part of "index-compatibility.pending.cocci" that
renames the global variables like "active_nr", which are a shorthand
to referencing (in that case) a struct member as "the_index.cache_nr".
In doing so move more of "index-compatibility.pending.cocci" to
"index-compatibility.cocci".
In the case of "active_nr" we'd have a textual conflict with
"ab/various-leak-fixes" in "next"[1]. Let's exclude that specific case
while moving the rule over from "pending".
1. 407b94280f (commit: discard partial cache before (re-)reading it,
2022-11-08)
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Apply a selection of rules in "index-compatibility.pending.cocci"
tree-wide, and in doing so migrate them to
"index-compatibility.cocci".
As in preceding commits the only manual changes here are the macro
removals in "cache.h", and the update to the '*.cocci" rules. The rest
of the C code changes are the result of applying those updated rules.
Move rules for some rarely used cache compatibility macros from
"index-compatibility.pending.cocci" to "index-compatibility.cocci" and
apply them.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The discard_index() function has not returned non-zero since
7a51ed66f6 (Make on-disk index representation separate from in-core
one, 2008-01-14), but we've had various code in-tree still acting as
though that might be the case.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Since 4aab5b46f4 (Make read-cache.c "the_index" free., 2007-04-01)
we've been undergoing a slow migration away from these macros, but
haven't made much progress since f8adbec9fe (cache.h: flip
NO_THE_INDEX_COMPATIBILITY_MACROS switch, 2019-01-24).
Let's move forward a bit by changing the users of those macros that
are rare enough that we can convert them in one go, and then remove
the compatibility shim.
The only manual change to the C code here is to "cache.h", the rest is
all the result of applying the new "index-compatibility.cocci".
Even though it's a one-off, let's keep the coccinelle rules for
now. We'll extend them in subsequent commits, and this will help
anything that's in-flight or out-of-tree to migrate.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The "active_alloc" macro added in 228e94f935 (Move index-related
variables into a structure., 2007-04-01) has not been used since
4aab5b46f4 (Make read-cache.c "the_index" free., 2007-04-01). Let's
remove it.
The rest of these are likewise unused, so let's not keep them
around. E.g. 12cd0bf9b0 (dir: stop using the index compatibility
macros, 2017-05-05) is the last use of "cache_dir_exists".
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The namespaces used by "log --decorate" from "refs/" hierarchy by
default has been tightened.
* ds/decorate-filter-tweak:
fetch: use ref_namespaces during prefetch
maintenance: stop writing log.excludeDecoration
log: create log.initialDecorationSet=all
log: add --clear-decorations option
log: add default decoration filter
log-tree: use ref_namespaces instead of if/else-if
refs: use ref_namespaces for replace refs base
refs: add array of ref namespaces
t4207: test coloring of grafted decorations
t4207: modernize test
refs: allow "HEAD" as decoration filter
Fixes to sparse index compatibility work for "reset" and "checkout"
commands.
* vd/sparse-reset-checkout-fixes:
unpack-trees: unpack new trees as sparse directories
cache.h: create 'index_name_pos_sparse()'
oneway_diff: handle removed sparse directories
checkout: fix nested sparse directory diff in sparse index
Expose a lot of "tech docs" via "git help" interface.
* ab/tech-docs-to-help:
docs: move http-protocol docs to man section 5
docs: move cruft pack docs to gitformat-pack
docs: move pack format docs to man section 5
docs: move signature docs to man section 5
docs: move index format docs to man section 5
docs: move protocol-related docs to man section 5
docs: move commit-graph format docs to man section 5
git docs: add a category for file formats, protocols and interfaces
git docs: add a category for user-facing file, repo and command UX
git help doc: use "<doc>" instead of "<guide>"
help.c: remove common category behavior from drop_prefix() behavior
help.c: refactor drop_prefix() to use a "switch" statement"
Add 'index_name_pos_sparse()', which behaves the same as 'index_name_pos()',
except that it does not expand a sparse index to search for an entry inside
a sparse directory.
'index_entry_exists()' was originally implemented in 20ec2d034c (reset: make
sparse-aware (except --mixed), 2021-11-29) as an alternative to
'index_name_pos()' to allow callers to search for an index entry without
expanding a sparse index. However, that particular use case only required
knowing whether the requested entry existed, so 'index_entry_exists()' does
not return the index positioning information provided by 'index_name_pos()'.
This patch implements 'index_name_pos_sparse()' to accommodate callers that
need the positioning information of 'index_name_pos()', but do not want to
expand the index.
Signed-off-by: Victoria Dye <vdye@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The git_replace_ref_base global is used to store the value of the
GIT_REPLACE_REF_BASE environment variable or the default of
"refs/replace/". This is initialized within setup_git_env().
The ref_namespaces array is a new centralized location for information
such as the ref namespace used for replace refs. Instead of having this
namespace stored in two places, use the ref_namespaces array instead.
For simplicity, create a local git_replace_ref_base variable wherever
the global was previously used.
Signed-off-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Continue the move of existing Documentation/technical/* protocol and
file-format documentation into our main documentation space by moving
the various documentation pertaining to the *.pack format and related
files, and updating things that refer to it to link to the new
location.
By moving these we can properly link from the newly created
gitformat-commit-graph to a gitformat-chunk-format page.
Integrating "Documentation/technical/bitmap-format.txt" and
"Documentation/technical/cruft-packs.txt" might logically be part of
this change, but as those cover parts of the wider "pack
format" (including associated files) that's documented outside of
"Documentation/technical/pack-format.txt" let's leave those for now,
subsequent commit(s) will address those.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
commit_rewrite_person() takes a commit buffer and replaces the idents
in the header with their canonical versions using the mailmap mechanism.
The name "commit_rewrite_person()" is misleading as it doesn't convey
what kind of rewrite are we going to do to the buffer. It also doesn't
clearly mention that the function will limit itself to the header part
of the buffer. The new name, "apply_mailmap_to_header()", expresses the
functionality of the function pretty clearly.
We intend to use apply_mailmap_to_header() in git-cat-file to replace
idents in the headers of commit and tag object buffers. So, we will be
extending this function to take tag objects buffer as well and replace
idents on the tagger header using the mailmap mechanism.
Mentored-by: Christian Couder <christian.couder@gmail.com>
Mentored-by: John Cai <johncai86@gmail.com>
Signed-off-by: Siddharth Asthana <siddharthasthana31@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
commit_rewrite_person() and rewrite_ident_line() are static functions
defined in revision.c.
Their usages are as follows:
- commit_rewrite_person() takes a commit buffer and replaces the author
and committer idents with their canonical versions using the mailmap
mechanism
- rewrite_ident_line() takes author/committer header lines from the
commit buffer and replaces the idents with their canonical versions
using the mailmap mechanism.
This patch moves commit_rewrite_person() and rewrite_ident_line() to
ident.c which contains many other functions related to idents like
split_ident_line(). By moving commit_rewrite_person() to ident.c, we
also intend to use it in git-cat-file to replace committer and author
idents from the headers to their canonical versions using the mailmap
mechanism. The function is moved as is for now to make it clear that
there are no other changes, but it will be renamed in a following
commit.
Mentored-by: Christian Couder <christian.couder@gmail.com>
Mentored-by: John Cai <johncai86@gmail.com>
Signed-off-by: Siddharth Asthana <siddharthasthana31@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"sparse-checkout" learns to work well with the sparse-index
feature.
* ds/sparse-sparse-checkout:
sparse-checkout: integrate with sparse index
p2000: add test for 'git sparse-checkout [add|set]'
sparse-index: complete partial expansion
sparse-index: partially expand directories
sparse-checkout: --no-sparse-index needs a full index
cache-tree: implement cache_tree_find_path()
sparse-index: introduce partially-sparse indexes
sparse-index: create expand_index()
t1092: stress test 'git sparse-checkout set'
t1092: refactor 'sparse-index contents' test
Introduce a filesystem-dependent mechanism to optimize the way the
bits for many loose object files are ensured to hit the disk
platter.
* ns/batch-fsync:
core.fsyncmethod: performance tests for batch mode
t/perf: add iteration setup mechanism to perf-lib
core.fsyncmethod: tests for batch mode
test-lib-functions: add parsing helpers for ls-files and ls-tree
core.fsync: use batch mode and sync loose objects by default on Windows
unpack-objects: use the bulk-checkin infrastructure
update-index: use the bulk-checkin infrastructure
builtin/add: add ODB transaction around add_files_to_cache
cache-tree: use ODB transaction around writing a tree
core.fsyncmethod: batched disk flushes for loose-objects
bulk-checkin: rebrand plug/unplug APIs as 'odb transactions'
bulk-checkin: rename 'state' variable and separate 'plugged' boolean
A future change will present a temporary, in-memory mode where the index
can both contain sparse directory entries but also not be completely
collapsed to the smallest possible sparse directories. This will be
necessary for modifying the sparse-checkout definition while using a
sparse index.
For now, convert the single-bit member 'sparse_index' in 'struct
index_state' to be a an 'enum sparse_index_mode' with three modes:
* INDEX_EXPANDED (0): No sparse directories exist. This is always the
case for repositories that do not use cone-mode sparse-checkout.
* INDEX_COLLAPSED: Sparse directories may exist. Files outside the
sparse-checkout cone are reduced to sparse directory entries whenever
possible.
* INDEX_PARTIALLY_SPARSE: Sparse directories may exist. Some file
entries outside the sparse-checkout cone may exist. Running
convert_to_sparse() may further reduce those files to sparse directory
entries.
The main reason to store this extra information is to allow
convert_to_sparse() to short-circuit when the index is already in
INDEX_EXPANDED mode but to actually do the necessary work when in
INDEX_PARTIALLY_SPARSE mode.
The INDEX_PARTIALLY_SPARSE mode will be used in an upcoming change.
Signed-off-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The path taken by "git multi-pack-index" command from the end user
was compared with path internally prepared by the tool withut first
normalizing, which lead to duplicated paths not being noticed,
which has been corrected.
* ds/midx-normalize-pathname-before-comparison:
cache: use const char * for get_object_directory()
multi-pack-index: use --object-dir real path
midx: use real paths in lookup_multi_pack_index()
The get_object_directory() method returns the exact string stored at
the_repository->objects->odb->path. The return type of "char *" implies
that the caller must keep track of the buffer and free() it when
complete. This causes significant problems later when the ODB is
accessed.
Use "const char *" as the return type to avoid this confusion. There are
no current callers that care about the non-const definition.
Signed-off-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Git for Windows has defaulted to core.fsyncObjectFiles=true since
September 2017. We turn on syncing of loose object files with batch mode
in upstream Git so that we can get broad coverage of the new code
upstream.
We don't actually do fsyncs in the most of the test suite, since
GIT_TEST_FSYNC is set to 0. However, we do exercise all of the
surrounding batch mode code since GIT_TEST_FSYNC merely makes the
maybe_fsync wrapper always appear to succeed.
Signed-off-by: Neeraj Singh <neerajsi@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When adding many objects to a repo with `core.fsync=loose-object`,
the cost of fsync'ing each object file can become prohibitive.
One major source of the cost of fsync is the implied flush of the
hardware writeback cache within the disk drive. This commit introduces
a new `core.fsyncMethod=batch` option that batches up hardware flushes.
It hooks into the bulk-checkin odb-transaction functionality, takes
advantage of tmp-objdir, and uses the writeout-only support code.
When the new mode is enabled, we do the following for each new object:
1a. Create the object in a tmp-objdir.
2a. Issue a pagecache writeback request and wait for it to complete.
At the end of the entire transaction when unplugging bulk checkin:
1b. Issue an fsync against a dummy file to flush the log and hardware
writeback cache, which should by now have seen the tmp-objdir writes.
2b. Rename all of the tmp-objdir files to their final names.
3b. When updating the index and/or refs, we assume that Git will issue
another fsync internal to that operation. This is not the default
today, but the user now has the option of syncing the index and there
is a separate patch series to implement syncing of refs.
On a filesystem with a singular journal that is updated during name
operations (e.g. create, link, rename, etc), such as NTFS, HFS+, or XFS
we would expect the fsync to trigger a journal writeout so that this
sequence is enough to ensure that the user's data is durable by the time
the git command returns. This sequence also ensures that no object files
appear in the main object store unless they are fsync-durable.
Batch mode is only enabled if core.fsync includes loose-objects. If
the legacy core.fsyncObjectFiles setting is enabled, but core.fsync does
not include loose-objects, we will use file-by-file fsyncing.
In step (1a) of the sequence, the tmp-objdir is created lazily to avoid
work if no loose objects are ever added to the ODB. We use a tmp-objdir
to maintain the invariant that no loose-objects are visible in the main
ODB unless they are properly fsync-durable. This is important since
future ODB operations that try to create an object with specific
contents will silently drop the new data if an object with the target
hash exists without checking that the loose-object contents match the
hash. Only a full git-fsck would restore the ODB to a functional state
where dataloss doesn't occur.
In step (1b) of the sequence, we issue a fsync against a dummy file
created specifically for the purpose. This method has a little higher
cost than using one of the input object files, but makes adding new
callers of this mechanism easier, since we don't need to figure out
which object file is "last" or risk sharing violations by caching the fd
of the last object file.
_Performance numbers_:
Linux - Hyper-V VM running Kernel 5.11 (Ubuntu 20.04) on a fast SSD.
Mac - macOS 11.5.1 running on a Mac mini on a 1TB Apple SSD.
Windows - Same host as Linux, a preview version of Windows 11.
Adding 500 files to the repo with 'git add' Times reported in seconds.
object file syncing | Linux | Mac | Windows
--------------------|-------|-------|--------
disabled | 0.06 | 0.35 | 0.61
fsync | 1.88 | 11.18 | 2.47
batch | 0.15 | 0.41 | 1.53
Signed-off-by: Neeraj Singh <neerajsi@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
