This hasn't been used since 17ddc66e70 (convert report_path_error to
take struct pathspec, 2013-07-14), as the names in the struct will have
already been prefixed when they were parsed.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Make the match_patchspec API and friends take an index_state instead
of assuming the_index in dir.c. All external call sites are converted
blindly to keep the patch simple and retain current behavior.
Individual call sites may receive further updates to use the right
index instead of the_index.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Conversion from uchar[20] to struct object_id continues.
* bc/object-id: (42 commits)
merge-one-file: compute empty blob object ID
add--interactive: compute the empty tree value
Update shell scripts to compute empty tree object ID
sha1_file: only expose empty object constants through git_hash_algo
dir: use the_hash_algo for empty blob object ID
sequencer: use the_hash_algo for empty tree object ID
cache-tree: use is_empty_tree_oid
sha1_file: convert cached object code to struct object_id
builtin/reset: convert use of EMPTY_TREE_SHA1_BIN
builtin/receive-pack: convert one use of EMPTY_TREE_SHA1_HEX
wt-status: convert two uses of EMPTY_TREE_SHA1_HEX
submodule: convert several uses of EMPTY_TREE_SHA1_HEX
sequencer: convert one use of EMPTY_TREE_SHA1_HEX
merge: convert empty tree constant to the_hash_algo
builtin/merge: switch tree functions to use object_id
builtin/am: convert uses of EMPTY_TREE_SHA1_BIN to the_hash_algo
sha1-file: add functions for hex empty tree and blob OIDs
builtin/receive-pack: avoid hard-coded constants for push certs
diff: specify abbreviation size in terms of the_hash_algo
upload-pack: replace use of several hard-coded constants
...
Moving a submodule that itself has submodule in it with "git mv"
forgot to make necessary adjustment to the nested sub-submodules;
now the codepath learned to recurse into the submodules.
* sb/submodule-move-nested:
submodule: fixup nested submodules after moving the submodule
submodule-config: remove submodule_from_cache
submodule-config: add repository argument to submodule_from_{name, path}
submodule-config: allow submodule_free to handle arbitrary repositories
grep: remove "repo" arg from non-supporting funcs
submodule.h: drop declaration of connect_work_tree_and_git_dir
Convert the exclude_sha1 member of struct untracked_cache_dir and rename
it to exclude_oid. Eliminate several hard-coded integral constants, and
update a function name that referred to SHA-1.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
connect_work_tree_and_git_dir is used to connect a submodule worktree with
its git directory and vice versa after events that require a reconnection
such as moving around the working tree. As submodules can have nested
submodules themselves, we'd also want to fix the nested submodules when
asked to. Add an option to recurse into the nested submodules and connect
them as well.
As submodules are identified by their name (which determines their git
directory in relation to their superproject's git directory) internally
and by their path in the working tree of the superproject, we need to
make sure that the mapping of name <-> path is kept intact. We can do
that in the git-mv command by writing out the gitmodules file first
and then forcing a reload of the submodule config machinery.
Signed-off-by: Stefan Beller <sbeller@google.com>
Reviewed-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Some bugs around "untracked cache" feature have been fixed.
* nd/fix-untracked-cache-invalidation:
dir.c: ignore paths containing .git when invalidating untracked cache
dir.c: stop ignoring opendir() error in open_cached_dir()
dir.c: fix missing dir invalidation in untracked code
dir.c: avoid stat() in valid_cached_dir()
status: add a failing test showing a core.untrackedCache bug
read_directory() code ignores all paths named ".git" even if it's not
a valid git repository. See treat_path() for details. Since ".git" is
basically invisible to read_directory(), when we are asked to
invalidate a path that contains ".git", we can safely ignore it
because the slow path would not consider it anyway.
This helps when fsmonitor is used and we have a real ".git" repo at
worktree top. Occasionally .git/index will be updated and if the
fsmonitor hook does not filter it, untracked cache is asked to
invalidate the path ".git/index".
Without this patch, we invalidate the root directory unncessarily,
which:
- makes read_directory() fall back to slow path for root directory
(slower)
- makes the index dirty (because UNTR extension is updated). Depending
on the index size, writing it down could also be slow.
A note about the new "safe_path" knob. Since this new check could be
relatively expensive, avoid it when we know it's not needed. If the
path comes from the index, it can't contain ".git". If it does
contain, we may be screwed up at many more levels, not just this one.
Noticed-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Convert the declaration of struct sha1_stat. Adjust all usages of this
struct and replace hash{clr,cmp,cpy} with oid{clr,cmp,cpy} wherever
possible. Rename it to struct oid_stat.
Rename static function load_sha1_stat to load_oid_stat.
Remove macro EMPTY_BLOB_SHA1_BIN, as it's no longer used.
Signed-off-by: Patryk Obara <patryk.obara@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In preparation for implementing narrow/partial clone, the object
walking machinery has been taught a way to tell it to "filter" some
objects from enumeration.
* jh/object-filtering:
rev-list: support --no-filter argument
list-objects-filter-options: support --no-filter
list-objects-filter-options: fix 'keword' typo in comment
pack-objects: add list-objects filtering
rev-list: add list-objects filtering support
list-objects: filter objects in traverse_commit_list
oidset: add iterator methods to oidset
oidmap: add oidmap iterator methods
dir: allow exclusions from blob in addition to file
Refactor add_excludes() to separate the reading of the
exclude file into a buffer and the parsing of the buffer
into exclude_list items.
Add add_excludes_from_blob_to_list() to allow an exclude
file be specified with an OID without assuming a local
worktree or index exists.
Refactor read_skip_worktree_file_from_index() and add
do_read_blob() to eliminate duplication of preliminary
processing of blob contents.
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Reviewed-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We learned to talk to watchman to speed up "git status" and other
operations that need to see which paths have been modified.
* bp/fsmonitor:
fsmonitor: preserve utf8 filenames in fsmonitor-watchman log
fsmonitor: read entirety of watchman output
fsmonitor: MINGW support for watchman integration
fsmonitor: add a performance test
fsmonitor: add a sample integration script for Watchman
fsmonitor: add test cases for fsmonitor extension
split-index: disable the fsmonitor extension when running the split index test
fsmonitor: add a test tool to dump the index extension
update-index: add fsmonitor support to update-index
ls-files: Add support in ls-files to display the fsmonitor valid bit
fsmonitor: add documentation for the fsmonitor extension.
fsmonitor: teach git to optionally utilize a file system monitor to speed up detecting new or changed files.
update-index: add a new --force-write-index option
preload-index: add override to enable testing preload-index
bswap: add 64 bit endianness helper get_be64
Teach the status command more flexibility in how ignored files are
reported. Currently, the reporting of ignored files and untracked
files are linked. You cannot control how ignored files are reported
independently of how untracked files are reported (i.e. `all` vs
`normal`). This makes it impossible to show untracked files with the
`all` option, but show ignored files with the `normal` option.
This work 1) adds the ability to control the reporting of ignored
files independently of untracked files and 2) introduces the concept
of status reporting ignored paths that explicitly match an ignored
pattern. There are 2 benefits to these changes: 1) if a consumer needs
all untracked files but not all ignored files, there is a performance
benefit to not scanning all contents of an ignored directory and 2)
returning ignored files that explicitly match a path allow a consumer
to make more informed decisions about when a status result might be
stale.
This commit implements --ignored=matching with --untracked-files=all.
The following commit will implement --ignored=matching with
--untracked=files=normal.
As an example of where this flexibility could be useful is that our
application (Visual Studio) runs the status command and presents the
output. It shows all untracked files individually (e.g. using the
'--untracked-files==all' option), and would like to know about which
paths are ignored. It uses information about ignored paths to make
decisions about when the status result might have changed.
Additionally, many projects place build output into directories inside
a repository's working directory (e.g. in "bin/" and "obj/"
directories). Normal usage is to explicitly ignore these 2 directory
names in the .gitignore file (rather than or in addition to the *.obj
pattern).If an application could know that these directories are
explicitly ignored, it could infer that all contents are ignored as
well and make better informed decisions about files in these
directories. It could infer that any changes under these paths would
not affect the output of status. Additionally, there can be a
significant performance benefit by avoiding scanning through ignored
directories.
When status is set to report matching ignored files, it has the
following behavior. Ignored files and directories that explicitly
match an exclude pattern are reported. If an ignored directory matches
an exclude pattern, then the path of the directory is returned. If a
directory does not match an exclude pattern, but all of its contents
are ignored, then the contained files are reported instead of the
directory.
Signed-off-by: Jameson Miller <jamill@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When the index is read from disk, the fsmonitor index extension is used
to flag the last known potentially dirty index entries. The registered
core.fsmonitor command is called with the time the index was last
updated and returns the list of files changed since that time. This list
is used to flag any additional dirty cache entries and untracked cache
directories.
We can then use this valid state to speed up preload_index(),
ie_match_stat(), and refresh_cache_ent() as they do not need to lstat()
files to detect potential changes for those entries marked
CE_FSMONITOR_VALID.
In addition, if the untracked cache is turned on valid_cached_dir() can
skip checking directories for new or changed files as fsmonitor will
invalidate the cache only for those directories that have been
identified as having potential changes.
To keep the CE_FSMONITOR_VALID state accurate during git operations;
when git updates a cache entry to match the current state on disk,
it will now set the CE_FSMONITOR_VALID bit.
Inversely, anytime git changes a cache entry, the CE_FSMONITOR_VALID bit
is cleared and the corresponding untracked cache directory is marked
invalid.
Signed-off-by: Ben Peart <benpeart@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Similar functions exist in apply.c and builtin/show-branch.c for
counting the number of slashes in a string. Also in the later
patches, we introduce a third caller for the same. Hence, we unify
it now by cleaning the existing functions and declaring a common
function count_slashes in dir.h and implementing it in dir.c to
remove this code duplication.
Mentored-by: Christian Couder <christian.couder@gmail.com>
Mentored-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Prathamesh Chavan <pc44800@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"git clean -d" used to clean directories that has ignored files,
even though the command should not lose ignored ones without "-x".
"git status --ignored" did not list ignored and untracked files
without "-uall". These have been corrected.
* sl/clean-d-ignored-fix:
clean: teach clean -d to preserve ignored paths
dir: expose cmp_name() and check_contains()
dir: hide untracked contents of untracked dirs
dir: recurse into untracked dirs for ignored files
t7061: status --ignored should search untracked dirs
t7300: clean -d should skip dirs with ignored files
We want to use cmp_name() and check_contains() (which both compare
`struct dir_entry`s, the former in terms of the sort order, the latter
in terms of whether one lexically contains another) outside of dir.c,
so we have to (1) change their linkage and (2) rename them as
appropriate for the global namespace. The second is achieved by
renaming cmp_name() to cmp_dir_entry() and check_contains() to
check_dir_entry_contains().
Signed-off-by: Samuel Lijin <sxlijin@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When we taught read_directory_recursive() to recurse into untracked
directories in search of ignored files given DIR_SHOW_IGNORED_TOO, that
had the side effect of teaching it to collect the untracked contents of
untracked directories. It doesn't always make sense to return these,
though (we do need them for `clean -d`), so we introduce a flag
(DIR_KEEP_UNTRACKED_CONTENTS) to control whether or not read_directory()
strips dir->entries of the untracked contents of untracked dirs.
We also introduce check_contains() to check if one dir_entry corresponds
to a path which contains the path corresponding to another dir_entry.
This also fixes known breakages in t7061, since status --ignored now
searches untracked directories for ignored files.
Signed-off-by: Samuel Lijin <sxlijin@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When a submodule has its git dir inside the working dir, the submodule
support for checkout that we plan to add in a later patch will fail.
Add functionality to migrate the git directory to be absorbed
into the superprojects git directory.
The newly added code in this patch is structured such that other areas of
Git can also make use of it. The code in the submodule--helper is a mere
wrapper and option parser for the function
`absorb_git_dir_into_superproject`, that takes care of embedding the
submodules git directory into the superprojects git dir. That function
makes use of the more abstract function for this use case
`relocate_gitdir`, which can be used by e.g. the worktree code eventually
to move around a git directory.
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
That function was primarily used by submodule code, but the function
itself is not inherently about submodules. In the next patch we'll
introduce relocate_git_dir, which can be used by worktrees as well,
so find a neutral middle ground in dir.h.
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Pathspecs can be a bit tricky when trying to apply them to submodules.
The main challenge is that the pathspecs will be with respect to the
superproject and not with respect to paths in the submodule. The
approach this patch takes is to pass in the identical pathspec from the
superproject to the submodule in addition to the submodule-prefix, which
is the path from the root of the superproject to the submodule, and then
we can compare an entry in the submodule prepended with the
submodule-prefix to the pathspec in order to determine if there is a
match.
This patch also permits the pathspec logic to perform a prefix match against
submodules since a pathspec could refer to a file inside of a submodule.
Due to limitations in the wildmatch logic, a prefix match is only done
literally. If any wildcard character is encountered we'll simply punt
and produce a false positive match. More accurate matching will be done
once inside the submodule. This is due to the superproject not knowing
what files could exist in the submodule.
Signed-off-by: Brandon Williams <bmwill@google.com>
Reviewed-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Further preparatory work on the refs API before the pluggable
backend series can land.
* mh/split-under-lock: (33 commits)
lock_ref_sha1_basic(): only handle REF_NODEREF mode
commit_ref_update(): remove the flags parameter
lock_ref_for_update(): don't resolve symrefs
lock_ref_for_update(): don't re-read non-symbolic references
refs: resolve symbolic refs first
ref_transaction_update(): check refname_is_safe() at a minimum
unlock_ref(): move definition higher in the file
lock_ref_for_update(): new function
add_update(): initialize the whole ref_update
verify_refname_available(): adjust constness in declaration
refs: don't dereference on rename
refs: allow log-only updates
delete_branches(): use resolve_refdup()
ref_transaction_commit(): correctly report close_ref() failure
ref_transaction_create(): disallow recursive pruning
refs: make error messages more consistent
lock_ref_sha1_basic(): remove unneeded local variable
read_raw_ref(): move docstring to header file
read_raw_ref(): improve docstring
read_raw_ref(): rename symref argument to referent
...
The experimental "multiple worktree" feature gains more safety to
forbid operations on a branch that is checked out or being actively
worked on elsewhere, by noticing that e.g. it is being rebased.
* nd/worktree-various-heads:
branch: do not rename a branch under bisect or rebase
worktree.c: check whether branch is bisected in another worktree
wt-status.c: split bisect detection out of wt_status_get_state()
worktree.c: check whether branch is rebased in another worktree
worktree.c: avoid referencing to worktrees[i] multiple times
wt-status.c: make wt_status_check_rebase() work on any worktree
wt-status.c: split rebase detection out of wt_status_get_state()
path.c: refactor and add worktree_git_path()
worktree.c: mark current worktree
worktree.c: make find_shared_symref() return struct worktree *
worktree.c: store "id" instead of "git_dir"
path.c: add git_common_path() and strbuf_git_common_path()
dir.c: rename str(n)cmp_icase to fspath(n)cmp
Add a docstring for the remove_dir_recursively() function and the
REMOVE_DIR_* flags that can be passed to it.
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
These functions compare two paths that are taken from file system.
Depending on the running file system, paths may need to be compared
case-sensitively or not, and maybe even something else in future. The
current names do not convey that well.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
It was largely replaced by fnmatch_icase_mem() and its last use was in
84b8b5d (remove match_pathspec() in favor of match_pathspec_depth() -
2013-07-14).
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The values defined by the macro EXC_FLAG_* (1, 4, 8, 16) are stored
in fields of the structs "pattern" and "exclude", some functions
arguments and a local variable. None of these uses its most
significant bit in any special way and there is no good reason to
use a signed integer for them.
And while we're at it, document "flags" of "exclude" to explicitly
state the values it's supposed to take on.
Signed-off-by: Saurav Sachidanand <sauravsachidanand@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Given path "a" and the pattern "a", it's matched. But if we throw path
"a/b" to pattern "a", the code fails to realize that if "a" matches
"a" then "a/b" should also be matched.
When the pattern is matched the first time, we can mark it "sticky", so
that all files and dirs inside the matched path also matches. This is a
simpler solution than modify all match scenarios to fix that.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
It is not a good idea to compare kernel versions and disable
the untracked cache if it changes, as people may upgrade and
still want the untracked cache to work. So let's just
compare work tree locations and kernel name to decide if we
should disable it.
Also storing many locations in the ident field and comparing
to any of them can be dangerous if GIT_WORK_TREE is used with
different values. So let's just store one location, the
location of the current work tree.
The downside is that untracked cache can only be used by one
type of OS for now. Exporting a git repo to different clients
via a network to e.g. Linux and Windows means that only one
can use the untracked cache.
If the location changed in the ident field and we still want
an untracked cache, let's delete the cache and recreate it.
Note that if an untracked cache has been created by a
previous Git version, then the kernel version is stored in
the ident field. As we now compare with just the kernel
name the comparison will fail and the untracked cache will
be disabled until it's recreated.
Helped-by: Torsten Bögershausen <tboegi@web.de>
Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Factor out code into remove_untracked_cache(), which will be used
in a later commit.
Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Factor out code into new_untracked_cache() and
add_untracked_cache(), which will be used
in later commits.
Helped-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Teach the index to optionally remember already seen untracked files
to speed up "git status" in a working tree with tons of cruft.
* nd/untracked-cache: (24 commits)
git-status.txt: advertisement for untracked cache
untracked cache: guard and disable on system changes
mingw32: add uname()
t7063: tests for untracked cache
update-index: test the system before enabling untracked cache
update-index: manually enable or disable untracked cache
status: enable untracked cache
untracked-cache: temporarily disable with $GIT_DISABLE_UNTRACKED_CACHE
untracked cache: mark index dirty if untracked cache is updated
untracked cache: print stats with $GIT_TRACE_UNTRACKED_STATS
untracked cache: avoid racy timestamps
read-cache.c: split racy stat test to a separate function
untracked cache: invalidate at index addition or removal
untracked cache: load from UNTR index extension
untracked cache: save to an index extension
ewah: add convenient wrapper ewah_serialize_strbuf()
untracked cache: don't open non-existent .gitignore
untracked cache: mark what dirs should be recursed/saved
untracked cache: record/validate dir mtime and reuse cached output
untracked cache: make a wrapper around {open,read,close}dir()
...
The expected call sequence is for the caller to use match_pathspec()
repeatedly on a set of pathspecs, accumulating the "hits" in a
separate array, and then call this function to diagnose a pathspec
that never matched anything, as that can indicate a typo from the
command line, e.g. "git commit Maekfile".
Many builtin commands use this function from builtin/ls-files.c,
which is not a very healthy arrangement. ls-files might have been
the first command to feel the need for such a helper, but the need
is shared by everybody who uses the "match and then report" pattern.
Move it to dir.c where match_pathspec() is defined.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
If the user enables untracked cache, then
- move worktree to an unsupported filesystem
- or simply upgrade OS
- or move the whole (portable) disk from one machine to another
- or access a shared fs from another machine
there's no guarantee that untracked cache can still function properly.
Record the worktree location and OS footprint in the cache. If it
changes, err on the safe side and disable the cache. The user can
'update-index --untracked-cache' again to make sure all conditions are
met.
This adds a new requirement that setup_git_directory* must be called
before read_cache() because we need worktree location by then, or the
cache is dropped.
This change does not cover all bases, you can fool it if you try
hard. The point is to stop accidents.
Helped-by: Eric Sunshine <sunshine@sunshineco.com>
Helped-by: brian m. carlson <sandals@crustytoothpaste.net>
Helped-by: Torsten Bögershausen <tboegi@web.de>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Ideally we should implement untracked_cache_remove_from_index() and
untracked_cache_add_to_index() so that they update untracked cache
right away instead of invalidating it and wait for read_directory()
next time to deal with it. But that may need some more work in
unpack-trees.c. So stay simple as the first step.
The new call in add_index_entry_with_check() may look strange because
new calls usually stay close to cache_tree_invalidate_path(). We do it
a bit later than c_t_i_p() in this function because if it's about
replacing the entry with the same name, we don't care (but cache-tree
does).
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Helped-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
If we redo this thing in a functional style, we would have one struct
untracked_dir as input tree and another as output. The input is used
for verification. The output is a brand new tree, reflecting current
worktree.
But that means recreate a lot of dir nodes even if a lot could be
shared between input and output trees in good cases. So we go with the
messy but efficient way, combining both input and output trees into
one. We need a way to know which node in this combined tree belongs to
the output. This is the purpose of this "recurse" flag.
"valid" bit can't be used for this because it's about data of the node
except the subdirs. When we invalidate a directory, we want to keep
cached data of the subdirs intact even though we don't really know
what subdir still exists (yet). Then we check worktree to see what
actual subdir remains on disk. Those will have 'recurse' bit set
again. If cached data for those are still valid, we may be able to
avoid computing exclude files for them. Those subdirs that are deleted
will have 'recurse' remained clear and their 'valid' bits do not
matter.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The main readdir loop in read_directory_recursive() is replaced with a
new one that checks if cached results of a directory is still valid.
If a file is added or removed from the index, the containing directory
is invalidated (but not its subdirs). If directory's mtime is changed,
the same happens. If a .gitignore is updated, the containing directory
and all subdirs are invalidated recursively. If dir_struct#flags or
other conditions change, the cache is ignored.
If a directory is invalidated, we opendir/readdir/closedir and run the
exclude machinery on that directory listing as usual. If untracked
cache is also enabled, we'll update the cache along the way. If a
directory is validated, we simply pull the untracked listing out from
the cache. The cache also records the list of direct subdirs that we
have to recurse in. Fully excluded directories are seen as "untracked
files".
In the best case when no dirs are invalidated, read_directory()
becomes a series of
stat(dir), open(.gitignore), fstat(), read(), close() and optionally
hash_sha1_file()
For comparison, standard read_directory() is a sequence of
opendir(), readdir(), open(.gitignore), fstat(), read(), close(), the
expensive last_exclude_matching() and closedir().
We already try not to open(.gitignore) if we know it does not exist,
so open/fstat/read/close sequence does not apply to every
directory. The sequence could be reduced further, as noted in
prep_exclude() in another patch. So in theory, the entire best-case
read_directory sequence could be reduced to a series of stat() and
nothing else.
This is not a silver bullet approach. When you compile a C file, for
example, the old .o file is removed and a new one with the same name
created, effectively invalidating the containing directory's cache
(but not its subdirectories). If your build process touches every
directory, this cache adds extra overhead for nothing, so it's a good
idea to separate generated files from tracked files.. Editors may use
the same strategy for saving files. And of course you're out of luck
running your repo on an unsupported filesystem and/or operating system.
Helped-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>