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660 commits

Author SHA1 Message Date
Tao Klerks e6a653554b untracked-cache: support '--untracked-files=all' if configured
Untracked cache was originally designed to only work with
"--untracked-files=normal", and is bypassed when
"--untracked-files=all" is requested, but this causes performance
issues for UI tooling that wants to see "all" on a frequent basis.

On the other hand, the conditions that altogether prevented
applicability to the "all" mode no longer seem to apply, after
several major refactors in recent years; this possibility was
discussed in
81153d02-8e7a-be59-e709-e90cd5906f3a@jeffhostetler.com and
CABPp-BFiwzzUgiTj_zu+vF5x20L0=1cf25cHwk7KZQj2YkVzXw@mail.gmail.com,
and somewhat confirmed experimentally by several users using a
version of this patch to use untracked cache with -uall for about a
year.

When 'git status' runs without using the untracked cache, on a large
repo, on windows, with fsmonitor, it can run very slowly. This can
make GUIs that need to use "-uall" (and therefore currently bypass
untracked cache) unusable when fsmonitor is enabled, on such large
repos.

To partially address this, align the supported directory flags for the
stored untracked cache data with the git config. If a user specifies
an '--untracked-files=' commandline parameter that does not align with
their 'status.showuntrackedfiles' config value, then the untracked
cache will be ignored - as it is for other unsupported situations like
when a pathspec is specified.

If the previously stored flags no longer match the current
configuration, but the currently-applicable flags do match the current
configuration, then discard the previously stored untracked cache
data.

For most users there will be no change in behavior. Users who need
'--untracked-files=all' to perform well will now have the option of
setting "status.showuntrackedfiles" to "all" for better / more
consistent performance.

Users who need '--untracked-files=all' to perform well for their
tooling AND prefer to avoid the verbosity of "all" when running
git status explicitly without options... are out of luck for now (no
change).

Users who have the "status.showuntrackedfiles" config set to "all"
and yet frequently explicitly call
'git status --untracked-files=normal' (and use the untracked cache)
are the only ones who will be disadvantaged by this change. Their
"--untracked-files=normal" calls will, after this change, no longer
use the untracked cache.

Signed-off-by: Tao Klerks <tao@klerks.biz>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-04-01 10:16:42 -07:00
Junio C Hamano 190f9bf62a Merge branch 'vd/sparse-read-tree'
"git read-tree" has been made to be aware of the sparse-index
feature.

* vd/sparse-read-tree:
  read-tree: make three-way merge sparse-aware
  read-tree: make two-way merge sparse-aware
  read-tree: narrow scope of index expansion for '--prefix'
  read-tree: integrate with sparse index
  read-tree: expand sparse checkout test coverage
  read-tree: explicitly disallow prefixes with a leading '/'
  status: fix nested sparse directory diff in sparse index
  sparse-index: prevent repo root from becoming sparse
2022-03-16 17:53:08 -07:00
Junio C Hamano 430883a70c Merge branch 'ab/object-file-api-updates'
Object-file API shuffling.

* ab/object-file-api-updates:
  object-file API: pass an enum to read_object_with_reference()
  object-file.c: add a literal version of write_object_file_prepare()
  object-file API: have hash_object_file() take "enum object_type"
  object API: rename hash_object_file_literally() to write_*()
  object-file API: split up and simplify check_object_signature()
  object API users + docs: check <0, not !0 with check_object_signature()
  object API docs: move check_object_signature() docs to cache.h
  object API: correct "buf" v.s. "map" mismatch in *.c and *.h
  object-file API: have write_object_file() take "enum object_type"
  object-file API: add a format_object_header() function
  object-file API: return "void", not "int" from hash_object_file()
  object-file.c: split up declaration of unrelated variables
2022-03-16 17:53:08 -07:00
Junio C Hamano 47e0380289 Merge branch 'tk/empty-untracked-cache'
The untracked cache newly computed weren't written back to the
on-disk index file when there is no other change to the index,
which has been corrected.

* tk/empty-untracked-cache:
  untracked-cache: write index when populating empty untracked cache
  t7519: populate untracked cache before test
  t7519: avoid file to index mtime race for untracked cache
2022-03-16 17:53:07 -07:00
Victoria Dye 287fd17e3a sparse-index: prevent repo root from becoming sparse
Prevent the repository root from being collapsed into a sparse directory by
treating an empty path as "inside the sparse-checkout". When collapsing a
sparse index (e.g. in 'git sparse-checkout reapply'), the root directory
typically could not become a sparse directory due to the presence of in-cone
root-level files and directories. However, if no such in-cone files or
directories were present, there was no explicit check signaling that the
"repository root path" (an empty string, in the case of
'convert_to_sparse(...)') was in-cone, and a sparse directory index entry
would be created from the repository root directory.

The documentation in Documentation/git-sparse-checkout.txt explicitly states
that the files in the root directory are expected to be in-cone for a
cone-mode sparse-checkout. Collapsing the root into a sparse directory entry
violates that assumption, as sparse directory entries are expected to be
outside the sparse cone and have SKIP_WORKTREE enabled. This invalid state
in turn causes issues with commands that interact with the index, e.g.
'git status'.

Treating an empty (root) path as in-cone prevents the creation of a root
sparse directory in 'convert_to_sparse(...)'. Because the repository root is
otherwise never compared with sparse patterns (in both cone-mode and
non-cone sparse-checkouts), the new check does not cause additional changes
to how sparse patterns are applied.

Helped-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Victoria Dye <vdye@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-03-01 12:36:00 -08:00
Tao Klerks 317956d912 untracked-cache: write index when populating empty untracked cache
It is expected that an empty/unpopulated untracked cache structure can
be written to the index - by update-index, or by a "git status" call
that sees the untracked cache should be enabled and is not, but is
running with options that make the untracked cache non-applicable in
that run (eg a pathspec).

Currently, if that happens, then subsequent "git status" calls end up
populating the untracked cache, but not writing the index (not saving
their work) - so the performance outcome is almost identical to the
cache being altogether disabled.

This continues until the index gets written with the untracked cache
populated, for some *other* reason, such as a working tree change.

Detect the condition where an empty untracked cache exists in the
index and we will collect the list of untracked paths, and queue an
index write under that condition, so that the collected untracked
paths can be written out to the untracked cache extension in the
index.

This change depends on previous fixes to t7519 for the "ignore .git
changes when invalidating UNTR" test case to pass - before this fix,
the test never actually did anything as it was not set up correctly.

Signed-off-by: Tao Klerks <tao@klerks.biz>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-02-28 10:02:18 -08:00
Ævar Arnfjörð Bjarmason 44439c1c58 object-file API: have hash_object_file() take "enum object_type"
Change the hash_object_file() function to take an "enum
object_type".

Since a preceding commit all of its callers are passing either
"{commit,tree,blob,tag}_type", or the result of a call to type_name(),
the parse_object() caller that would pass NULL is now using
stream_object_signature().

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-02-25 17:16:32 -08:00
Derrick Stolee 26b8946421 dir: force untracked cache with core.untrackedCache
The GIT_FORCE_UNTRACKED_CACHE environment variable writes the untracked
cache more frequently than the core.untrackedCache config variable. This
is due to how read_directory() handles the creation of an untracked
cache.

Before this change, Git would not create the untracked cache extension
for an index that did not already have one. Users would need to run a
command such as 'git update-index --untracked-cache' before the index
would actually contain an untracked cache.

In particular, users noticed that the untracked cache would not appear
even with core.untrackedCache=true. Some users reported setting
GIT_FORCE_UNTRACKED_CACHE=1 in their engineering system environment to
ensure the untracked cache would be created.

The decision to not write the untracked cache without an environment
variable tracks back to fc9ecbeb9 (dir.c: don't flag the index as dirty
for changes to the untracked cache, 2018-02-05). The motivation of that
change is that writing the index is expensive, and if the untracked
cache is the only thing that needs to be written, then it is more
expensive than the benefit of the cache. However, this also means that
the untracked cache never gets populated, so the user who enabled it via
config does not actually get the extension until running 'git
update-index --untracked-cache' manually or using the environment
variable.

We have had a version of this change in the microsoft/git fork for a few
major releases now. It has been working well to get users into a good
state. Yes, that first index write is slow, but the remaining index
writes are much faster than they would be without this change.

Signed-off-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-02-17 14:47:13 -08:00
Junio C Hamano 09481fec21 Merge branch 'ds/sparse-checkout-malformed-pattern-fix'
Certain sparse-checkout patterns that are valid in non-cone mode
led to segfault in cone mode, which has been corrected.

* ds/sparse-checkout-malformed-pattern-fix:
  sparse-checkout: refuse to add to bad patterns
  sparse-checkout: fix OOM error with mixed patterns
  sparse-checkout: fix segfault on malformed patterns
2022-01-10 11:52:49 -08:00
Junio C Hamano da81d473fc Merge branch 'en/keep-cwd'
Many git commands that deal with working tree files try to remove a
directory that becomes empty (i.e. "git switch" from a branch that
has the directory to another branch that does not would attempt
remove all files in the directory and the directory itself).  This
drops users into an unfamiliar situation if the command was run in
a subdirectory that becomes subject to removal due to the command.
The commands have been taught to keep an empty directory if it is
the directory they were started in to avoid surprising users.

* en/keep-cwd:
  t2501: simplify the tests since we can now assume desired behavior
  dir: new flag to remove_dir_recurse() to spare the original_cwd
  dir: avoid incidentally removing the original_cwd in remove_path()
  stash: do not attempt to remove startup_info->original_cwd
  rebase: do not attempt to remove startup_info->original_cwd
  clean: do not attempt to remove startup_info->original_cwd
  symlinks: do not include startup_info->original_cwd in dir removal
  unpack-trees: add special cwd handling
  unpack-trees: refuse to remove startup_info->original_cwd
  setup: introduce startup_info->original_cwd
  t2501: add various tests for removing the current working directory
2022-01-05 14:01:28 -08:00
Derrick Stolee a3eca58445 sparse-checkout: refuse to add to bad patterns
When in cone mode sparse-checkout, it is unclear how 'git
sparse-checkout add <dir1> ...' should behave if the existing
sparse-checkout file does not match the cone mode patterns. Change the
behavior to fail with an error message about the existing patterns.

Also, all cone mode patterns start with a '/' character, so add that
restriction. This is necessary for our example test 'cone mode: warn on
bad pattern', but also requires modifying the example sparse-checkout
file we use to test the warnings related to recognizing cone mode
patterns.

This error checking would cause a failure further down the test script
because of a test that adds non-cone mode patterns without cleaning them
up. Perform that cleanup as part of the test now.

Reviewed-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-12-30 14:39:57 -08:00
Derrick Stolee a481d4378c sparse-checkout: fix segfault on malformed patterns
Then core.sparseCheckoutCone is enabled, the sparse-checkout patterns are
used to populate two hashsets that accelerate pattern matching. If the user
modifies the sparse-checkout file outside of the 'sparse-checkout' builtin,
then strange patterns can happen, triggering some error checks.

One of these error checks is possible to hit when some special characters
exist in a line. A warning message is correctly written to stderr, but then
there is additional logic that attempts to remove the line from the hashset
and free the data. This leads to a segfault in the 'git sparse-checkout
list' command because it iterates over the contents of the hashset, which is
now invalid.

The fix here is to stop trying to remove from the hashset. In addition,
we disable cone mode sparse-checkout because of the malformed data. This
results in the pattern-matching working with a possibly-slower
algorithm, but using the patterns as they are in the sparse-checkout
file.

This also changes the behavior of commands such as 'git sparse-checkout
list' because the output patterns will be the contents of the
sparse-checkout file instead of the list of directories. This is an
existing behavior for other types of bad patterns.

Add a test that triggers the segfault without the code change.

Reported-by: John Burnett <johnburnett@johnburnett.com>
Reviewed-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-12-30 14:39:57 -08:00
Elijah Newren 580a5d7f75 dir: new flag to remove_dir_recurse() to spare the original_cwd
remove_dir_recurse(), and its non-static wrapper called
remove_dir_recursively(), both take flags for modifying its behavior.
As with the previous commits, we would generally like to protect
the original_cwd, but we want to forced user commands (e.g. 'git rm -rf
...') or other special cases to remove it.  Add a flag for this purpose.
After reading through every caller of remove_dir_recursively() in the
current codebase, there was only one that should be adjusted and that
one only in a very unusual circumstance.  Add a pair of new testcases to
highlight that very specific case involving submodules && --git-dir &&
--work-tree.

Acked-by: Derrick Stolee <stolee@gmail.com>
Acked-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-12-09 13:33:13 -08:00
Elijah Newren 63bbe8beb7 dir: avoid incidentally removing the original_cwd in remove_path()
Modern git often tries to avoid leaving empty directories around when
removing files.  Originally, it did not bother.  This behavior started
with commit 80e21a9ed8 (merge-recursive::removeFile: remove empty
directories, 2005-11-19), stating the reason simply as:

    When the last file in a directory is removed as the result of a
    merge, try to rmdir the now-empty directory.

This was reimplemented in C and renamed to remove_path() in commit
e1b3a2cad7 ("Build-in merge-recursive", 2008-02-07), but was still
internal to merge-recursive.

This trend towards removing leading empty directories continued with
commit d9b814cc97 (Add builtin "git rm" command, 2006-05-19), which
stated the reasoning as:

    The other question is what to do with leading directories. The old
    "git rm" script didn't do anything, which is somewhat inconsistent.
    This one will actually clean up directories that have become empty
    as a result of removing the last file, but maybe we want to have a
    flag to decide the behaviour?

remove_path() in dir.c was added in 4a92d1bfb7 (Add remove_path: a
function to remove as much as possible of a path, 2008-09-27), because
it was noted that we had two separate implementations of the same idea
AND both were buggy.  It described the purpose of the function as

    a function to remove as much as possible of a path

Why remove as much as possible?  Well, at the time we probably would
have said something like:

  * removing leading directories makes things feel tidy
  * removing leading directories doesn't hurt anything so long as they
    had no files in them.

But I don't believe those reasons hold when the empty directory happens
to be the current working directory we inherited from our parent
process.  Leaving the parent process in a deleted directory can cause
user confusion when subsequent processes fail: any git command, for
example, will immediately fail with

    fatal: Unable to read current working directory: No such file or directory

Other commands may similarly get confused.  Modify remove_path() so that
the empty leading directories it also deletes does not include the
current working directory we inherited from our parent process.  I have
looked through every caller of remove_path() in the current codebase to
make sure that all should take this change.

Acked-by: Derrick Stolee <stolee@gmail.com>
Acked-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-12-09 13:33:13 -08:00
Junio C Hamano eef0a8e7c1 Merge branch 'ds/add-rm-with-sparse-index' into maint
Regression fix for 2.34

* ds/add-rm-with-sparse-index:
  dir: revert "dir: select directories correctly"
2021-11-23 14:48:11 -08:00
Junio C Hamano 1bf2673685 Merge branch 'ds/add-rm-with-sparse-index'
Regression fix for 2.34

* ds/add-rm-with-sparse-index:
  dir: revert "dir: select directories correctly"
2021-11-22 18:40:10 -08:00
Derrick Stolee 33c5d6c845 dir: revert "dir: select directories correctly"
This reverts commit f6526728f9.

The change in f652672 (dir: select directories correctly, 2021-09-24)
caused a regression in directory-based matches with non-cone-mode
patterns, especially for .gitignore patterns. A test is included to
prevent this regression in the future.

The commit ed495847 (dir: fix pattern matching on dirs, 2021-09-24) was
reverted in 5ceb663 (dir: fix directory-matching bug, 2021-11-02) for
similar reasons. Neither commit changed tests, and tests added later in
the series continue to pass when these commits are reverted.

Reported-by: Danial Alihosseini <danial.alihosseini@gmail.com>
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-11-22 14:53:23 -08:00
Junio C Hamano 36f0a2e20f Merge branch 'ds/add-rm-with-sparse-index'
Regression fix.

* ds/add-rm-with-sparse-index:
  dir: fix directory-matching bug
2021-11-03 13:32:28 -07:00
Derrick Stolee 5ceb663e92 dir: fix directory-matching bug
This reverts the change from ed49584 (dir: fix pattern matching on dirs,
2021-09-24), which claimed to fix a directory-matching problem without a
test case. It turns out to _create_ a bug, but it is a bit subtle.

The bug would have been revealed by the first of two tests being added to
t0008-ignores.sh. The first uses a pattern "/git/" inside the a/.gitignores
file, which matches against 'a/git/foo' but not 'a/git-foo/bar'. This test
would fail before the revert.

The second test shows what happens if the test instead uses a pattern "git/"
and this test passes both before and after the revert.

The difference in these two cases are due to how
last_matching_pattern_from_list() checks patterns both if they have the
PATTERN_FLAG_MUSTBEDIR and PATTERN_FLAG_NODIR flags. In the case of "git/",
the PATTERN_FLAG_NODIR is also provided, making the change in behavior in
match_pathname() not affect the end result of
last_matching_pattern_from_list().

Reported-by: Glen Choo <chooglen@google.com>
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-11-03 10:10:36 -07:00
Junio C Hamano 68fb83b58e Merge branch 'mt/fix-add-rm-with-sparse-index'
Fix-up to a topic already merged to 'master'.

* mt/fix-add-rm-with-sparse-index:
  add, rm, mv: fix bug that prevents the update of non-sparse dirs
2021-10-29 15:43:16 -07:00
Matheus Tavares 20141e322c add, rm, mv: fix bug that prevents the update of non-sparse dirs
These three commands recently learned to avoid updating paths outside
the sparse checkout even if they are missing the SKIP_WORKTREE bit. This
is done using path_in_sparse_checkout(), which checks whether a given
path matches the current list of sparsity rules, similar to what
clear_ce_flags() does when we run "git sparse checkout init" or "git
sparse-checkout reapply". However, clear_ce_flags() uses a recursive
approach, applying the match results from parent directories on paths
that get the UNDECIDED result, whereas path_in_sparse_checkout() only
attempts to match the full path and immediately considers UNDECIDED as
NOT_MATCHED. This makes the function miss matches with leading
directories. For example, if the user has the sparsity patterns "!/a"
and "b/", add, rm, and mv will fail to update the path "a/b/c" and end
up displaying a warning about it being outside the sparse checkout even
though it isn't. This problem only occurs in full pattern mode as the
pattern matching functions never return UNDECIDED for cone mode.

To fix this, replicate the recursive behavior of clear_ce_flags() in
path_in_sparse_checkout(), falling back to the parent directory match
when a path gets the UNDECIDED result. (If this turns out to be too
expensive in some cases, we may want to later add some form of caching
to accelerate multiple queries within the same directory. This is not
implemented in this patch, though.) Also add two tests for each affected
command (add, rm, and mv) to check that they behave correctly with the
recursive pattern matching. The first test would previously fail without
this patch while the second already succeeded. It is added mostly to
make sure that we are not breaking the existing pattern matching for
directories that are really sparse, and also as a protection against any
future regressions.

Two other existing tests had to be changed as well: one test in t3602
checks that "git rm -r <dir>" won't remove sparse entries, but it didn't
allow the non-sparse entries inside <dir> to be removed. The other one,
in t7002, tested that "git mv" would correctly display a warning message
for sparse paths, but it accidentally expected the message to include
two non-sparse paths as well.

Signed-off-by: Matheus Tavares <matheus.bernardino@usp.br>
Acked-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-28 08:46:07 -07:00
Junio C Hamano 2d498a7c89 Merge branch 'ds/add-rm-with-sparse-index'
"git add", "git mv", and "git rm" have been adjusted to avoid
updating paths outside of the sparse-checkout definition unless
the user specifies a "--sparse" option.

* ds/add-rm-with-sparse-index:
  advice: update message to suggest '--sparse'
  mv: refuse to move sparse paths
  rm: skip sparse paths with missing SKIP_WORKTREE
  rm: add --sparse option
  add: update --renormalize to skip sparse paths
  add: update --chmod to skip sparse paths
  add: implement the --sparse option
  add: skip tracked paths outside sparse-checkout cone
  add: fail when adding an untracked sparse file
  dir: fix pattern matching on dirs
  dir: select directories correctly
  t1092: behavior for adding sparse files
  t3705: test that 'sparse_entry' is unstaged
2021-10-13 15:15:56 -07:00
Derrick Stolee ed4958477b dir: fix pattern matching on dirs
Within match_pathname(), one successful matching category happens when
the pattern is equal to its non-wildcard prefix. At this point, we have
checked that the input 'pathname' matches the pattern up to the prefix
length, and then we subtraced that length from both 'patternlen' and
'namelen'.

In the case of a directory match, this prefix match should be
sufficient. However, the success condition only cared about _exact_
equality here. Instead, we should allow any path that agrees on this
prefix in the case of PATTERN_FLAG_MUSTBEDIR.

This case was not tested before because of the way unpack_trees() would
match a parent directory before visiting the contained paths. This
approach is changing, so we must change this comparison.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-28 10:31:02 -07:00
Derrick Stolee f6526728f9 dir: select directories correctly
When matching a path against a list of patterns, the ones that require a
directory match previously did not work when a filename is specified.
This was fine when all pattern-matching was done within methods such as
unpack_trees() that check a directory before recursing into the
contained files. However, other commands will start matching individual
files against pattern lists without that recursive approach.

The last_matching_pattern_from_list() logic performs some checks on the
filetype of a path within the index when the PATTERN_FLAG_MUSTBEDIR flag
is set. This works great when setting SKIP_WORKTREE bits within
unpack_trees(), but doesn't work well when passing an arbitrary path
such as a file within a matching directory.

We extract the logic around determining the file type, but attempt to
avoid checking the filesystem if the parent directory already matches
the sparse-checkout patterns. The new path_matches_dir_pattern() method
includes a 'path_parent' parameter that is used to store the parent
directory of 'pathname' between multiple pattern matching tests. This is
loaded lazily, only on the first pattern it finds that has the
PATTERN_FLAG_MUSTBEDIR flag.

If we find that a path has a parent directory, we start by checking to
see if that parent directory matches the pattern. If so, then we do not
need to query the index for the type (which can be expensive). If we
find that the parent does not match, then we still must check the type
from the index for the given pathname.

Note that this does not affect cone mode pattern matching, but instead
the more general -- and slower -- full pattern set. Thus, this does not
affect the sparse index.

Helped-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-28 10:31:02 -07:00
Junio C Hamano f7511fdfbd Merge branch 'jt/submodule-name-to-gitdir'
Code refactoring.

* jt/submodule-name-to-gitdir:
  submodule: extract path to submodule gitdir func
2021-09-23 13:44:49 -07:00
Junio C Hamano dc89c34d9e Merge branch 'ds/sparse-index-ignored-files'
In cone mode, the sparse-index code path learned to remove ignored
files (like build artifacts) outside the sparse cone, allowing the
entire directory outside the sparse cone to be removed, which is
especially useful when the sparse patterns change.

* ds/sparse-index-ignored-files:
  sparse-checkout: clear tracked sparse dirs
  sparse-index: add SPARSE_INDEX_MEMORY_ONLY flag
  attr: be careful about sparse directories
  sparse-checkout: create helper methods
  sparse-index: use WRITE_TREE_MISSING_OK
  sparse-index: silently return when cache tree fails
  unpack-trees: fix nested sparse-dir search
  sparse-index: silently return when not using cone-mode patterns
  t7519: rewrite sparse index test
2021-09-20 15:20:44 -07:00
Jonathan Tan ce125d431a submodule: extract path to submodule gitdir func
We currently store each submodule gitdir in ".git/modules/<name>", but
this has problems with some submodule naming schemes, as described in a
comment in submodule_name_to_gitdir() in this patch.

Extract the determination of the location of a submodule's gitdir into
its own function submodule_name_to_gitdir(). For now, the problem
remains unsolved, but this puts us in a better position for finding a
solution.

This was motivated, at $DAYJOB, by a part of Android's repo hierarchy
[1]. In particular, there is a repo "build", and several repos of the
form "build/<name>".

This is based on earlier work by Brandon Williams [2].

[1] https://android.googlesource.com/platform/
[2] https://lore.kernel.org/git/20180808223323.79989-2-bmwill@google.com/

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-15 12:59:12 -07:00
Derrick Stolee 02155c8c00 sparse-checkout: create helper methods
As we integrate the sparse index into more builtins, we occasionally
need to check the sparse-checkout patterns to see if a path is within
the sparse-checkout cone. Create some helper methods that help
initialize the patterns and check for pattern matching to make this
easier.

The existing callers of commands like get_sparse_checkout_patterns() use
a custom 'struct pattern_list' that is not necessarily the one in the
'struct index_state', so there are not many previous uses that could
adopt these helpers. There are just two in builtin/add.c and
sparse-index.c that can use path_in_sparse_checkout().

We add a path_in_cone_mode_sparse_checkout() as well that will only
return false if the path is outside of the sparse-checkout definition
_and_ the sparse-checkout patterns are in cone mode.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Reviewed-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-07 22:41:10 -07:00
Atharva Raykar ed86301f68 dir: libify and export helper functions from clone.c
These functions can be useful to other parts of Git. Let's move them to
dir.c, while renaming them to be make their functionality more explicit.

Signed-off-by: Atharva Raykar <raykar.ath@gmail.com>
Mentored-by: Christian Couder <christian.couder@gmail.com>
Mentored-by: Shourya Shukla <periperidip@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-08-10 11:45:11 -07:00
René Scharfe 7431842325 use fspathhash() everywhere
cf2dc1c238 (speed up alt_odb_usable() with many alternates, 2021-07-07)
introduced the function fspathhash() for calculating path hashes while
respecting the configuration option core.ignorecase.  Call it instead of
open-coding it; the resulting code is shorter and less repetitive.

Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-07-30 12:14:27 -07:00
Junio C Hamano b271a3034f Merge branch 'ds/status-with-sparse-index'
"git status" codepath learned to work with sparsely populated index
without hydrating it fully.

* ds/status-with-sparse-index:
  t1092: document bad sparse-checkout behavior
  fsmonitor: integrate with sparse index
  wt-status: expand added sparse directory entries
  status: use sparse-index throughout
  status: skip sparse-checkout percentage with sparse-index
  diff-lib: handle index diffs with sparse dirs
  dir.c: accept a directory as part of cone-mode patterns
  unpack-trees: unpack sparse directory entries
  unpack-trees: rename unpack_nondirectories()
  unpack-trees: compare sparse directories correctly
  unpack-trees: preserve cache_bottom
  t1092: add tests for status/add and sparse files
  t1092: expand repository data shape
  t1092: replace incorrect 'echo' with 'cat'
  sparse-index: include EXTENDED flag when expanding
  sparse-index: skip indexes with unmerged entries
2021-07-28 13:18:02 -07:00
Junio C Hamano e5cc59c77c Merge branch 'ew/many-alternate-optim'
Optimization for repositories with many alternate object store.

* ew/many-alternate-optim:
  oidtree: a crit-bit tree for odb_loose_cache
  oidcpy_with_padding: constify `src' arg
  make object_directory.loose_objects_subdir_seen a bitmap
  avoid strlen via strbuf_addstr in link_alt_odb_entry
  speed up alt_odb_usable() with many alternates
2021-07-28 13:17:57 -07:00
Derrick Stolee 69bdbdb0ee dir.c: accept a directory as part of cone-mode patterns
When we have sparse directory entries in the index, we want to compare
that directory against sparse-checkout patterns. Those pattern matching
algorithms are built expecting a file path, not a directory path. This
is especially important in the "cone mode" patterns which will match
files that exist within the "parent directories" as well as the
recursive directory matches.

If path_matches_pattern_list() is given a directory, we can add a fake
filename ("-") to the directory and get the same results as before,
assuming we are in cone mode. Since sparse index requires cone mode
patterns, this is an acceptable assumption.

Reviewed-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-07-14 13:42:49 -07:00
Eric Wong cf2dc1c238 speed up alt_odb_usable() with many alternates
With many alternates, the duplicate check in alt_odb_usable()
wastes many cycles doing repeated fspathcmp() on every existing
alternate.  Use a khash to speed up lookups by odb->path.

Since the kh_put_* API uses the supplied key without
duplicating it, we also take advantage of it to replace both
xstrdup() and strbuf_release() in link_alt_odb_entry() with
strbuf_detach() to avoid the allocation and copy.

In a test repository with 50K alternates and each of those 50K
alternates having one alternate each (for a total of 100K total
alternates); this speeds up lookup of a non-existent blob from
over 16 minutes to roughly 2.7 seconds on my busy workstation.

Note: all underlying git object directories were small and
unpacked with only loose objects and no packs.  Having to load
packs increases times significantly.

Signed-off-by: Eric Wong <e@80x24.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-07-07 17:21:12 -07:00
Ævar Arnfjörð Bjarmason ce93a4c612 dir.[ch]: replace dir_init() with DIR_INIT
Remove the dir_init() function and replace it with a DIR_INIT
macro. In many cases in the codebase we need to initialize things with
a function for good reasons, e.g. needing to call another function on
initialization. The "dir_init()" function was not one such case, and
could trivially be replaced with a more idiomatic macro initialization
pattern.

The only place where we made use of its use of memset() was in
dir_clear() itself, which resets the contents of an an existing struct
pointer. Let's use the new "memcpy() a 'blank' struct on the stack"
idiom to do that reset.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-07-01 12:32:22 -07:00
Junio C Hamano 329d63e7be Merge branch 'en/dir-traversal'
Fix-up to a topic that is already in 'master'.

* en/dir-traversal:
  dir: introduce readdir_skip_dot_and_dotdot() helper
  dir: update stale description of treat_directory()
  Revert "dir: update stale description of treat_directory()"
  Revert "dir: introduce readdir_skip_dot_and_dotdot() helper"
2021-05-28 13:03:00 +09:00
Elijah Newren 906fc557b7 dir: introduce readdir_skip_dot_and_dotdot() helper
Many places in the code were doing
    while ((d = readdir(dir)) != NULL) {
        if (is_dot_or_dotdot(d->d_name))
            continue;
        ...process d...
    }
Introduce a readdir_skip_dot_and_dotdot() helper to make that a one-liner:
    while ((d = readdir_skip_dot_and_dotdot(dir)) != NULL) {
        ...process d...
    }

This helper particularly simplifies checks for empty directories.

Also use this helper in read_cached_dir() so that our statistics are
consistent across platforms.  (In other words, read_cached_dir() should
have been using is_dot_or_dotdot() and skipping such entries, but did
not and left it to treat_path() to detect and mark such entries as
path_none.)

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-05-27 14:02:37 +09:00
Derrick Stolee eef814828f dir: update stale description of treat_directory()
The documentation comment for treat_directory() was originally written
in 095952 (Teach directory traversal about subprojects, 2007-04-11)
which was before the 'struct dir_struct' split its bitfield of named
options into a 'flags' enum in 7c4c97c0 (Turn the flags in struct
dir_struct into a single variable, 2009-02-16). When those flags
changed, the comment became stale, since members like
'show_other_directories' transitioned into flags like
DIR_SHOW_OTHER_DIRECTORIES.

Update the comments for treat_directory() to use these flag names rather
than the old member names.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-05-27 14:02:37 +09:00
Junio C Hamano 2c9f1bfdb4 Revert "dir: update stale description of treat_directory()"
This reverts commit 4e689d8171,
to be replaced with a reworked version.
2021-05-27 14:02:37 +09:00
Junio C Hamano 1df046bcff Revert "dir: introduce readdir_skip_dot_and_dotdot() helper"
This reverts commit b548f0f156,
to be replaced with a reworked version.
2021-05-27 14:02:37 +09:00
Junio C Hamano 33be431c0c Merge branch 'en/dir-traversal'
"git clean" and "git ls-files -i" had confusion around working on
or showing ignored paths inside an ignored directory, which has
been corrected.

* en/dir-traversal:
  dir: introduce readdir_skip_dot_and_dotdot() helper
  dir: update stale description of treat_directory()
  dir: traverse into untracked directories if they may have ignored subfiles
  dir: avoid unnecessary traversal into ignored directory
  t3001, t7300: add testcase showcasing missed directory traversal
  t7300: add testcase showing unnecessary traversal into ignored directory
  ls-files: error out on -i unless -o or -c are specified
  dir: report number of visited directories and paths with trace2
  dir: convert trace calls to trace2 equivalents
2021-05-20 08:54:59 +09:00
Elijah Newren b548f0f156 dir: introduce readdir_skip_dot_and_dotdot() helper
Many places in the code were doing
    while ((d = readdir(dir)) != NULL) {
        if (is_dot_or_dotdot(d->d_name))
            continue;
        ...process d...
    }
Introduce a readdir_skip_dot_and_dotdot() helper to make that a one-liner:
    while ((d = readdir_skip_dot_and_dotdot(dir)) != NULL) {
        ...process d...
    }

This helper particularly simplifies checks for empty directories.

Also use this helper in read_cached_dir() so that our statistics are
consistent across platforms.  (In other words, read_cached_dir() should
have been using is_dot_or_dotdot() and skipping such entries, but did
not and left it to treat_path() to detect and mark such entries as
path_none.)

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-05-13 08:45:03 +09:00
Derrick Stolee 4e689d8171 dir: update stale description of treat_directory()
The documentation comment for treat_directory() was originally written
in 095952 (Teach directory traversal about subprojects, 2007-04-11)
which was before the 'struct dir_struct' split its bitfield of named
options into a 'flags' enum in 7c4c97c0 (Turn the flags in struct
dir_struct into a single variable, 2009-02-16). When those flags
changed, the comment became stale, since members like
'show_other_directories' transitioned into flags like
DIR_SHOW_OTHER_DIRECTORIES.

Update the comments for treat_directory() to use these flag names rather
than the old member names.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Reviewed-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-05-13 08:45:03 +09:00
Elijah Newren dd55fc0df1 dir: traverse into untracked directories if they may have ignored subfiles
A directory that is untracked does not imply that all files under it
should be categorized as untracked; in particular, if the caller is
interested in ignored files, many files or directories underneath the
untracked directory may be ignored.  We previously partially handled
this right with DIR_SHOW_IGNORED_TOO, but missed DIR_SHOW_IGNORED.  It
was not obvious, though, because the logic for untracked and excluded
files had been fused together making it harder to reason about.  The
previous commit split that logic out, making it easier to notice that
DIR_SHOW_IGNORED was missing.  Add it.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-05-13 08:45:03 +09:00
Elijah Newren aa6e1b21e5 dir: avoid unnecessary traversal into ignored directory
The show_other_directories case in treat_directory() tried to handle
both excludes and untracked files with the same logic, and mishandled
both the excludes and the untracked files in the process, in different
ways.  Split that logic apart, and then focus on the logic for the
excludes; a subsequent commit will address the logic for untracked
files.

For show_other_directories, an excluded directory means that
every path underneath that directory will also be excluded.  Given that
the calling code requested to just show directories when everything
under a directory had the same state (that's what the
"DIR_SHOW_OTHER_DIRECTORIES" flag means), we generally do not need to
traverse into such directories and can just immediately mark them as
ignored (i.e. as path_excluded).  The only reason we cannot just
immediately return path_excluded is the DIR_HIDE_EMPTY_DIRECTORIES flag
and the possibility that the ignored directory is an empty directory.
The code previously treated DIR_SHOW_IGNORED_TOO in most cases as an
exception as well, which was wrong.  It can sometimes reduce the number
of cases where we need to recurse (namely if
DIR_SHOW_IGNORED_TOO_MODE_MATCHING is also set), but should not be able
to increase the number of cases where we need to recurse.  Fix the logic
accordingly.

Some sidenotes about possible confusion with dir.c:

* "ignored" often refers to an untracked ignore", i.e. a file which is
  not tracked which matches one of the ignore/exclusion rules.  But you
  can also have a "tracked ignore", a tracked file that happens to match
  one of the ignore/exclusion rules and which dir.c has to worry about
  since "git ls-files -c -i" is supposed to list them.

* The dir code often uses "ignored" and "excluded" interchangeably,
  which you need to keep in mind while reading the code.

* "exclude" is used multiple ways in the code:

  * As noted above, "exclude" is often a synonym for "ignored".

  * The logic for parsing .gitignore files was re-used in
    .git/info/sparse-checkout, except there it is used to mark paths that
    the user wants to *keep*.  This was mostly addressed by commit
    65edd96aec ("treewide: rename 'exclude' methods to 'pattern'",
    2019-09-03), but every once in a while you'll find a comment about
    "exclude" referring to these patterns that might in fact be in use
    by the sparse-checkout machinery for inclusion rules.

  * The word "EXCLUDE" is also used for pathspec negation, as in
      (pathspec->items[3].magic & PATHSPEC_EXCLUDE)
    Thus if a user had a .gitignore file containing
      *~
      *.log
      !settings.log
    And then ran
      git add -- 'settings.*' ':^settings.log'
    Then :^settings.log is a pathspec negation making settings.log not
    be requested to be added even though all other settings.* files are
    being added.  Also, !settings.log in the gitignore file is a negative
    exclude pattern meaning that settings.log is normally a file we
    want to track even though all other *.log files are ignored.

Sometimes it feels like dir.c needs its own glossary with its many
definitions, including the multiply-defined terms.

Reported-by: Jason Gore <Jason.Gore@microsoft.com>
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-05-13 08:45:03 +09:00
Elijah Newren 7fe1ffdafa dir: report number of visited directories and paths with trace2
Provide more statistics in trace2 output that include the number of
directories and total paths visited by the directory traversal logic.
Subsequent patches will take advantage of this to ensure we do not
unnecessarily traverse into ignored directories.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-05-13 08:45:02 +09:00
Elijah Newren 7f9dd87922 dir: convert trace calls to trace2 equivalents
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-05-13 08:45:02 +09:00
Junio C Hamano aaa3c8065d Merge branch 'bc/hash-transition-interop-part-1'
SHA-256 transition.

* bc/hash-transition-interop-part-1:
  hex: print objects using the hash algorithm member
  hex: default to the_hash_algo on zero algorithm value
  builtin/pack-objects: avoid using struct object_id for pack hash
  commit-graph: don't store file hashes as struct object_id
  builtin/show-index: set the algorithm for object IDs
  hash: provide per-algorithm null OIDs
  hash: set, copy, and use algo field in struct object_id
  builtin/pack-redundant: avoid casting buffers to struct object_id
  Use the final_oid_fn to finalize hashing of object IDs
  hash: add a function to finalize object IDs
  http-push: set algorithm when reading object ID
  Always use oidread to read into struct object_id
  hash: add an algo member to struct object_id
2021-05-10 16:59:46 +09:00
Junio C Hamano 8e97852919 Merge branch 'ds/sparse-index-protections'
Builds on top of the sparse-index infrastructure to mark operations
that are not ready to mark with the sparse index, causing them to
fall back on fully-populated index that they always have worked with.

* ds/sparse-index-protections: (47 commits)
  name-hash: use expand_to_path()
  sparse-index: expand_to_path()
  name-hash: don't add directories to name_hash
  revision: ensure full index
  resolve-undo: ensure full index
  read-cache: ensure full index
  pathspec: ensure full index
  merge-recursive: ensure full index
  entry: ensure full index
  dir: ensure full index
  update-index: ensure full index
  stash: ensure full index
  rm: ensure full index
  merge-index: ensure full index
  ls-files: ensure full index
  grep: ensure full index
  fsck: ensure full index
  difftool: ensure full index
  commit: ensure full index
  checkout: ensure full index
  ...
2021-04-30 13:50:26 +09:00
brian m. carlson 14228447c9 hash: provide per-algorithm null OIDs
Up until recently, object IDs did not have an algorithm member, only a
hash.  Consequently, it was possible to share one null (all-zeros)
object ID among all hash algorithms.  Now that we're going to be
handling objects from multiple hash algorithms, it's important to make
sure that all object IDs have a correct algorithm field.

Introduce a per-algorithm null OID, and add it to struct hash_algo.
Introduce a wrapper function as well, and use it everywhere we used to
use the null_oid constant.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-04-27 16:31:39 +09:00
brian m. carlson 92e2cab96b Always use oidread to read into struct object_id
In the future, we'll want oidread to automatically set the hash
algorithm member for an object ID we read into it, so ensure we use
oidread instead of hashcpy everywhere we're copying a hash value into a
struct object_id.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-04-27 16:31:38 +09:00
Derrick Stolee d425f65127 dir: ensure full index
Before iterating over all cache entries, ensure that a sparse index is
expanded to a full index to avoid unexpected behavior.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Reviewed-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-04-14 13:47:32 -07:00
Derrick Stolee 847a9e5d4f *: remove 'const' qualifier for struct index_state
Several methods specify that they take a 'struct index_state' pointer
with the 'const' qualifier because they intend to only query the data,
not change it. However, we will be introducing a step very low in the
method stack that might modify a sparse-index to become a full index in
the case that our queries venture inside a sparse-directory entry.

This change only removes the 'const' qualifiers that are necessary for
the following change which will actually modify the implementation of
index_name_stage_pos().

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Reviewed-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-04-14 13:46:00 -07:00
Junio C Hamano 204333b015 Merge branch 'jk/open-dotgitx-with-nofollow'
It does not make sense to make ".gitattributes", ".gitignore" and
".mailmap" symlinks, as they are supposed to be usable from the
object store (think: bare repositories where HEAD:.mailmap etc. are
used).  When these files are symbolic links, we used to read the
contents of the files pointed by them by mistake, which has been
corrected.

* jk/open-dotgitx-with-nofollow:
  mailmap: do not respect symlinks for in-tree .mailmap
  exclude: do not respect symlinks for in-tree .gitignore
  attr: do not respect symlinks for in-tree .gitattributes
  exclude: add flags parameter to add_patterns()
  attr: convert "macro_ok" into a flags field
  add open_nofollow() helper
2021-03-22 14:00:22 -07:00
René Scharfe ca56dadb4b use CALLOC_ARRAY
Add and apply a semantic patch for converting code that open-codes
CALLOC_ARRAY to use it instead.  It shortens the code and infers the
element size automatically.

Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-03-13 16:00:09 -08:00
Junio C Hamano 9889cff6d6 Merge branch 'jh/untracked-cache-fix'
An under-allocation for the untracked cache data has been corrected.

* jh/untracked-cache-fix:
  dir: fix malloc of root untracked_cache_dir
2021-03-01 14:02:58 -08:00
Jeff Hostetler 6347d649bc dir: fix malloc of root untracked_cache_dir
Use FLEX_ALLOC_STR() to allocate the `struct untracked_cache_dir`
for the root directory.  Get rid of unsafe code that might fail to
initialize the `name` field (if FLEX_ARRAY is not 1).  This will
make it clear that we intend to have a structure with an empty
string following it.

A problem was observed on Windows where the length of the memset() was
too short, so the first byte of the name field was not zeroed.  This
resulted in the name field having garbage from a previous use of that
area of memory.

The record for the root directory was then written to the untracked-cache
extension in the index.  This garbage would then be visible to future
commands when they reloaded the untracked-cache extension.

Since the directory record for the root directory had garbage in the
`name` field, the `t/helper/test-tool dump-untracked-cache` tool
printed this garbage as the path prefix (rather than '/') for each
directory in the untracked cache as it recursed.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Reviewed-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-02-24 12:09:10 -08:00
Jeff King feb9b7792f exclude: do not respect symlinks for in-tree .gitignore
As with .gitattributes, we would like to make sure that .gitignore files
are handled consistently whether read from the index or from the
filesystem. Likewise, we would like to avoid reading out-of-tree files
pointed to by the symlinks, which could have security implications in
certain setups.

We can cover both by using open_nofollow() when opening the in-tree
files. We'll continue to follow links for core.excludesFile, as well as
$GIT_DIR/info/exclude.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-02-16 09:41:33 -08:00
Jeff King 1679d60bfc exclude: add flags parameter to add_patterns()
There are a number of callers of add_patterns() and its sibling
functions. Let's give them a "flags" parameter for adding new options
without having to touch each caller. We'll use this in a future patch to
add O_NOFOLLOW support. But for now each caller just passes 0.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-02-16 09:41:33 -08:00
Derrick Stolee dd23022acb sparse-checkout: load sparse-checkout patterns
A future feature will want to load the sparse-checkout patterns into a
pattern_list, but the current mechanism to do so is a bit complicated.
This is made difficult due to needing to find the sparse-checkout file
in different ways throughout the codebase.

The logic implemented in the new get_sparse_checkout_patterns() was
duplicated in populate_from_existing_patterns() in unpack-trees.c. Use
the new method instead, keeping the logic around handling the struct
unpack_trees_options.

The callers to get_sparse_checkout_filename() in
builtin/sparse-checkout.c manipulate the sparse-checkout file directly,
so it is not appropriate to replace logic in that file with
get_sparse_checkout_patterns().

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-01-23 17:14:07 -08:00
Junio C Hamano bf0a430f70 Merge branch 'en/strmap'
A specialization of hashmap that uses a string as key has been
introduced.  Hopefully it will see wider use over time.

* en/strmap:
  shortlog: use strset from strmap.h
  Use new HASHMAP_INIT macro to simplify hashmap initialization
  strmap: take advantage of FLEXPTR_ALLOC_STR when relevant
  strmap: enable allocations to come from a mem_pool
  strmap: add a strset sub-type
  strmap: split create_entry() out of strmap_put()
  strmap: add functions facilitating use as a string->int map
  strmap: enable faster clearing and reusing of strmaps
  strmap: add more utility functions
  strmap: new utility functions
  hashmap: provide deallocation function names
  hashmap: introduce a new hashmap_partial_clear()
  hashmap: allow re-use after hashmap_free()
  hashmap: adjust spacing to fix argument alignment
  hashmap: add usage documentation explaining hashmap_free[_entries]()
2020-11-21 15:14:38 -08:00
Junio C Hamano 03cd25ecbd Merge branch 'nk/dir-c-comment-update'
Update stale in-code comment.

* nk/dir-c-comment-update:
  dir.c: fix comments to agree with argument name
2020-11-02 13:17:42 -08:00
Elijah Newren 6da1a25814 hashmap: provide deallocation function names
hashmap_free(), hashmap_free_entries(), and hashmap_free_() have existed
for a while, but aren't necessarily the clearest names, especially with
hashmap_partial_clear() being added to the mix and lazy-initialization
now being supported.  Peff suggested we adopt the following names[1]:

  - hashmap_clear() - remove all entries and de-allocate any
    hashmap-specific data, but be ready for reuse

  - hashmap_clear_and_free() - ditto, but free the entries themselves

  - hashmap_partial_clear() - remove all entries but don't deallocate
    table

  - hashmap_partial_clear_and_free() - ditto, but free the entries

This patch provides the new names and converts all existing callers over
to the new naming scheme.

[1] https://lore.kernel.org/git/20201030125059.GA3277724@coredump.intra.peff.net/

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-11-02 12:15:50 -08:00
Alex Vandiver e5cf6d3df4 dir.c: fix comments to agree with argument name
Signed-off-by: Alex Vandiver <alexmv@dropbox.com>
Signed-off-by: Nipunn Koorapati <nipunn@dropbox.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-10-16 08:40:27 -07:00
Jeff King 842385b8a4 dir.c: drop unused "untracked" from treat_path_fast()
We don't use the untracked_cache_dir parameter that is passed in, but
instead look at the untracked_cache_dir inside the cached_dir struct we
are passed. It's been this way since the introduction of
treat_path_fast() in 91a2288b5f (untracked cache: record/validate dir
mtime and reuse cached output, 2015-03-08).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-30 12:53:48 -07:00
Junio C Hamano 0d9a8e33f9 Merge branch 'jk/leakfix'
Code clean-up.

* jk/leakfix:
  submodule--helper: fix leak of core.worktree value
  config: fix leak in git_config_get_expiry_in_days()
  config: drop git_config_get_string_const()
  config: fix leaks from git_config_get_string_const()
  checkout: fix leak of non-existent branch names
  submodule--helper: use strbuf_release() to free strbufs
  clear_pattern_list(): clear embedded hashmaps
2020-08-27 14:04:49 -07:00
Junio C Hamano ad00f44f54 Merge branch 'en/dir-clear'
Leakfix with code clean-up.

* en/dir-clear:
  dir: fix problematic API to avoid memory leaks
  dir: make clear_directory() free all relevant memory
2020-08-24 14:54:34 -07:00
Junio C Hamano 11f433f79c Merge branch 'en/dir-nonbare-embedded'
"ls-files -o" mishandled the top-level directory of another git
working tree that hangs in the current git working tree.

* en/dir-nonbare-embedded:
  dir: avoid prematurely marking nonbare repositories as matches
  t3000: fix some test description typos
2020-08-24 14:54:29 -07:00
Elijah Newren eceba53214 dir: fix problematic API to avoid memory leaks
The dir structure seemed to have a number of leaks and problems around
it.  First I noticed that parent_hashmap and recursive_hashmap were
being leaked (though Peff noticed and submitted fixes before me).  Then
I noticed in the previous commit that clear_directory() was only taking
responsibility for a subset of fields within dir_struct, despite the
fact that entries[] and ignored[] we allocated internally to dir.c.
That, of course, resulted in many callers either leaking or haphazardly
trying to free these arrays and their contents.

Digging further, I found that despite the pretty clear documentation
near the top of dir.h that folks were supposed to call clear_directory()
when the user no longer needed the dir_struct, there were four callers
that didn't bother doing that at all.  However, two of them clearly
thought about leaks since they had an UNLEAK(dir) directive, which to me
suggests that the method to free the data was too unclear.  I suspect
the non-obviousness of the API and its holes led folks to avoid it,
which then snowballed into further problems with the entries[],
ignored[], parent_hashmap, and recursive_hashmap problems.

Rename clear_directory() to dir_clear() to be more in line with other
data structures in git, and introduce a dir_init() to handle the
suggested memsetting of dir_struct to all zeroes.  I hope that a name
like "dir_clear()" is more clear, and that the presence of dir_init()
will provide a hint to those looking at the code that they need to look
for either a dir_clear() or a dir_free() and lead them to find
dir_clear().

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-08-18 17:17:31 -07:00
Elijah Newren dad4f23ce5 dir: make clear_directory() free all relevant memory
The calling convention for the dir API is supposed to end with a call to
clear_directory() to free up no longer needed memory.  However,
clear_directory() didn't free dir->entries or dir->ignored.  I believe
this was an oversight, but a number of callers noticed memory leaks and
started free'ing these.  Unfortunately, they did so somewhat haphazardly
(sometimes freeing the entries in the arrays, and sometimes only
free'ing the arrays themselves).  This suggests the callers weren't
trying to make sure any possible memory used might be free'd, but just
the memory they noticed their usecase definitely had allocated.

Fix this mess by moving all the duplicated free'ing logic into
clear_directory().  End by resetting dir to a pristine state so it could
be reused if desired.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-08-18 17:17:29 -07:00
Jeff King 8dc3156373 clear_pattern_list(): clear embedded hashmaps
Commit 96cc8ab531 (sparse-checkout: use hashmaps for cone patterns,
2019-11-21) added some auxiliary hashmaps to the pattern_list struct,
but they're leaked when clear_pattern_list() is called.

Signed-off-by: Jeff King <peff@peff.net>
Acked-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-08-14 10:48:12 -07:00
Elijah Newren ab282aa548 dir: avoid prematurely marking nonbare repositories as matches
Nonbare repositories are special directories.  Unlike normal directories
that we might recurse into to list the files they contain, nonbare
repositories must themselves match and then we always report only on the
nonbare repository directory itself and not on any of its contents.

Separately, when traversing directories to try to find untracked or
excluded files, we often think in terms of paths either matching the
specified pathspec, or not matching them.  However, there is a special
value that do_match_pathspec() uses named
MATCHED_RECURSIVELY_LEADING_PATHSPEC which means "this directory does
not match any pathspec BUT it is possible a file or directory underneath
it does."  That special value prevents us from prematurely thinking that
some directory and everything under it is irrelevant, but also allows us
to differentiate from "this is a match".

The combination of these two special cases was previously uncovered.
Add a test to the testsuite to cover it, and make sure that we return a
nonbare repository as a non-match if the best match it got was
MATCHED_RECURSIVELY_LEADING_PATHSPEC.

Reported-by: christian w <usebees@gmail.com>
Simplified-testcase-and-bisection-by: Kyle Meyer <kyle@kyleam.com>
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-08-12 12:26:47 -07:00
Junio C Hamano 82fafc77ba Merge branch 'en/fill-directory-exponential' into master
Fix to a regression introduced during 2.27 cycle.

* en/fill-directory-exponential:
  dir: check pathspecs before returning `path_excluded`
2020-07-30 13:20:36 -07:00
Martin Ågren cada7308ad dir: check pathspecs before returning path_excluded
In 95c11ecc73 ("Fix error-prone fill_directory() API; make it only
return matches", 2020-04-01), we taught `fill_directory()`, or more
specifically `treat_path()`, to check against any pathspecs so that we
could simplify the callers.

But in doing so, we added a slightly-too-early return for the "excluded"
case. We end up not checking the pathspecs, meaning we return
`path_excluded` when maybe we should return `path_none`. As a result,
`git status --ignored -- pathspec` might show paths that don't actually
match "pathspec".

Move the "excluded" check down to after we've checked any pathspecs.

Reported-by: Andreas Schwab <schwab@linux-m68k.org>
Reviewed-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Martin Ågren <martin.agren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-07-20 13:25:07 -07:00
Junio C Hamano 53674699c0 Merge branch 'en/clean-cleanups'
Code clean-up of "git clean" resulted in a fix of recent
performance regression.

* en/clean-cleanups:
  clean: optimize and document cases where we recurse into subdirectories
  clean: consolidate handling of ignored parameters
  dir, clean: avoid disallowed behavior
  dir: fix a few confusing comments
2020-06-25 12:27:45 -07:00
Junio C Hamano 64efa11e6b Merge branch 'en/do-match-pathspec-fix'
Use of negative pathspec, while collecting paths including
untracked ones in the working tree, was broken.

* en/do-match-pathspec-fix:
  dir: fix treatment of negated pathspecs
2020-06-17 21:54:03 -07:00
Elijah Newren 351ea1c3cb dir, clean: avoid disallowed behavior
dir.h documented quite clearly that DIR_SHOW_IGNORED and
DIR_SHOW_IGNORED_TOO are mutually exclusive, with a big comment to this
effect by the definition of both enum values.  However, a command like
   git clean -fx $DIR
would set both values for dir.flags.  I _think_ it happened to work
because:
  * As dir.h points out, DIR_KEEP_UNTRACKED_CONTENTS only takes effect
    if DIR_SHOW_IGNORED_TOO is set.
  * As coded, I believe DIR_SHOW_IGNORED would just happen to take
    precedence over DIR_SHOW_IGNORED_TOO in the code as currently
    constructed.
Which is a long way of saying "we just got lucky".

Fix clean.c to avoid setting these mutually exclusive values at the same
time, and add a check to dir.c that will throw a BUG() to prevent anyone
else from making this mistake.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-06-12 17:27:16 -07:00
Elijah Newren e6c0be9239 dir: fix a few confusing comments
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-06-12 17:27:16 -07:00
Elijah Newren f1f061e11d dir: fix treatment of negated pathspecs
do_match_pathspec() started life as match_pathspec_depth_1() and for
correctness was only supposed to be called from match_pathspec_depth().
match_pathspec_depth() was later renamed to match_pathspec(), so the
invariant we expect today is that do_match_pathspec() has no direct
callers outside of match_pathspec().

Unfortunately, this intention was lost with the renames of the two
functions, and additional calls to do_match_pathspec() were added in
commits 75a6315f74 ("ls-files: add pathspec matching for submodules",
2016-10-07) and 89a1f4aaf7 ("dir: if our pathspec might match files
under a dir, recurse into it", 2019-09-17).  Of course,
do_match_pathspec() had an important advantge over match_pathspec() --
match_pathspec() would hardcode flags to one of two values, and these
new callers needed to pass some other value for flags.  Also, although
calling do_match_pathspec() directly was incorrect, there likely wasn't
any difference in the observable end output, because the bug just meant
that fill_diretory() would recurse into unneeded directories.  Since
subsequent does-this-path-match checks on individual paths under the
directory would cause those extra paths to be filtered out, the only
difference from using the wrong function was unnecessary computation.

The second of those bad calls to do_match_pathspec() was involved -- via
either direct movement or via copying+editing -- into a number of later
refactors.  See commits 777b420347 ("dir: synchronize
treat_leading_path() and read_directory_recursive()", 2019-12-19),
8d92fb2927 ("dir: replace exponential algorithm with a linear one",
2020-04-01), and 95c11ecc73 ("Fix error-prone fill_directory() API; make
it only return matches", 2020-04-01).  The last of those introduced the
usage of do_match_pathspec() on an individual file, and thus resulted in
individual paths being returned that shouldn't be.

The problem with calling do_match_pathspec() instead of match_pathspec()
is that any negated patterns such as ':!unwanted_path` will be ignored.
Add a new match_pathspec_with_flags() function to fulfill the needs of
specifying special flags while still correctly checking negated
patterns, add a big comment above do_match_pathspec() to prevent others
from misusing it, and correct current callers of do_match_pathspec() to
instead use either match_pathspec() or match_pathspec_with_flags().

One final note is that DO_MATCH_LEADING_PATHSPEC needs special
consideration when working with DO_MATCH_EXCLUDE.  The point of
DO_MATCH_LEADING_PATHSPEC is that if we have a pathspec like
   */Makefile
and we are checking a directory path like
   src/module/component
that we want to consider it a match so that we recurse into the
directory because it _might_ have a file named Makefile somewhere below.
However, when we are using an exclusion pattern, i.e. we have a pathspec
like
   :(exclude)*/Makefile
we do NOT want to say that a directory path like
   src/module/component
is a (negative) match.  While there *might* be a file named 'Makefile'
somewhere below that directory, there could also be other files and we
cannot pre-emptively rule all the files under that directory out; we
need to recurse and then check individual files.  Adjust the
DO_MATCH_LEADING_PATHSPEC logic to only get activated for positive
pathspecs.

Reported-by: John Millikin <jmillikin@stripe.com>
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-06-05 15:02:16 -07:00
Junio C Hamano 6eacc39b6d Merge branch 'en/fill-directory-exponential'
The directory traversal code had redundant recursive calls which
made its performance characteristics exponential with respect to
the depth of the tree, which was corrected.

* en/fill-directory-exponential:
  completion: fix 'git add' on paths under an untracked directory
  Fix error-prone fill_directory() API; make it only return matches
  dir: replace double pathspec matching with single in treat_directory()
  dir: include DIR_KEEP_UNTRACKED_CONTENTS handling in treat_directory()
  dir: replace exponential algorithm with a linear one
  dir: refactor treat_directory to clarify control flow
  dir: fix confusion based on variable tense
  dir: fix broken comment
  dir: consolidate treat_path() and treat_one_path()
  dir: fix simple typo in comment
  t3000: add more testcases testing a variety of ls-files issues
  t7063: more thorough status checking
2020-04-29 16:15:31 -07:00
Elijah Newren 95c11ecc73 Fix error-prone fill_directory() API; make it only return matches
Traditionally, the expected calling convention for the dir.c API was:

    fill_directory(&dir, ..., pathspec)
    foreach entry in dir->entries:
        if (dir_path_match(entry, pathspec))
            process_or_display(entry)

This may have made sense once upon a time, because the fill_directory() call
could use cheap checks to avoid doing full pathspec matching, and an external
caller may have wanted to do other post-processing of the results anyway.
However:

    * this structure makes it easy for users of the API to get it wrong

    * this structure actually makes it harder to understand
      fill_directory() and the functions it uses internally.  It has
      tripped me up several times while trying to fix bugs and
      restructure things.

    * relying on post-filtering was already found to produce wrong
      results; pathspec matching had to be added internally for multiple
      cases in order to get the right results (see commits 404ebceda0
      (dir: also check directories for matching pathspecs, 2019-09-17)
      and 89a1f4aaf7 (dir: if our pathspec might match files under a
      dir, recurse into it, 2019-09-17))

    * it's bad for performance: fill_directory() already has to do lots
      of checks and knows the subset of cases where it still needs to do
      more checks.  Forcing external callers to do full pathspec
      matching means they must re-check _every_ path.

So, add the pathspec matching within the fill_directory() internals, and
remove it from external callers.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-04-01 11:11:31 -07:00
Elijah Newren 7f45ab2dca dir: replace double pathspec matching with single in treat_directory()
treat_directory() had a call to both do_match_pathspec() and
match_pathspec().  These calls have migrated through the code somewhat
since their introduction, but we don't actually need both.  Replace the
two calls with one, and while at it, move the check earlier in order to
reduce the need for callers of fill_directory() to do post-filtering of
results.

The next patch will address post-filtering more forcefully and provide
more relevant history and context.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-04-01 11:11:31 -07:00
Elijah Newren 1684644489 dir: include DIR_KEEP_UNTRACKED_CONTENTS handling in treat_directory()
Handling DIR_KEEP_UNTRACKED_CONTENTS within treat_directory() instead of
as a post-processing step in read_directory():
  * allows us to directly access and remove the relevant entries instead
    of needing to calculate which ones need to be removed
  * keeps the logic for directory handling in one location (and puts it
    closer the the logic for stripping out extra ignored entries, which
    seems logical).

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-04-01 11:11:31 -07:00
Elijah Newren 8d92fb2927 dir: replace exponential algorithm with a linear one
dir's read_directory_recursive() naturally operates recursively in order
to walk the directory tree.  Treating of directories is sometimes weird
because there are so many different permutations about how to handle
directories.  Some examples:

   * 'git ls-files -o --directory' only needs to know that a directory
     itself is untracked; it doesn't need to recurse into it to see what
     is underneath.

   * 'git status' needs to recurse into an untracked directory, but only
     to determine whether or not it is empty.  If there are no files
     underneath, the directory itself will be omitted from the output.
     If it is not empty, only the directory will be listed.

   * 'git status --ignored' needs to recurse into untracked directories
     and report all the ignored entries and then report the directory as
     untracked -- UNLESS all the entries under the directory are
     ignored, in which case we don't print any of the entries under the
     directory and just report the directory itself as ignored.  (Note
     that although this forces us to walk all untracked files underneath
     the directory as well, we strip them from the output, except for
     users like 'git clean' who also set DIR_KEEP_TRACKED_CONTENTS.)

   * For 'git clean', we may need to recurse into a directory that
     doesn't match any specified pathspecs, if it's possible that there
     is an entry underneath the directory that can match one of the
     pathspecs.  In such a case, we need to be careful to omit the
     directory itself from the list of paths (see commit 404ebceda0
     ("dir: also check directories for matching pathspecs", 2019-09-17))

Part of the tension noted above is that the treatment of a directory can
change based on the files within it, and based on the various settings
in dir->flags.  Trying to keep this in mind while reading over the code,
it is easy to think in terms of "treat_directory() tells us what to do
with a directory, and read_directory_recursive() is the thing that
recurses".  Since we need to look into a directory to know how to treat
it, though, it is quite easy to decide to (also) recurse into the
directory from treat_directory() by adding a read_directory_recursive()
call.  Adding such a call is actually fine, IF we make sure that
read_directory_recursive() does not also recurse into that same
directory.

Unfortunately, commit df5bcdf83a ("dir: recurse into untracked dirs
for ignored files", 2017-05-18), added exactly such a case to the code,
meaning we'd have two calls to read_directory_recursive() for an
untracked directory.  So, if we had a file named
   one/two/three/four/five/somefile.txt
and nothing in one/ was tracked, then 'git status --ignored' would
call read_directory_recursive() twice on the directory 'one/', and
each of those would call read_directory_recursive() twice on the
directory 'one/two/', and so on until read_directory_recursive() was
called 2^5 times for 'one/two/three/four/five/'.

Avoid calling read_directory_recursive() twice per level by moving a
lot of the special logic into treat_directory().

Since dir.c is somewhat complex, extra cruft built up around this over
time.  While trying to unravel it, I noticed several instances where the
first call to read_directory_recursive() would return e.g.
path_untracked for some directory and a later one would return e.g.
path_none, despite the fact that the directory clearly should have been
considered untracked.  The code happened to work due to the side-effect
from the first invocation of adding untracked entries to dir->entries;
this allowed it to get the correct output despite the supposed override
in return value by the later call.

I am somewhat concerned that there are still bugs and maybe even
testcases with the wrong expectation.  I have tried to carefully
document treat_directory() since it becomes more complex after this
change (though much of this complexity came from elsewhere that probably
deserved better comments to begin with).  However, much of my work felt
more like a game of whackamole while attempting to make the code match
the existing regression tests than an attempt to create an
implementation that matched some clear design.  That seems wrong to me,
but the rules of existing behavior had so many special cases that I had
a hard time coming up with some overarching rules about what correct
behavior is for all cases, forcing me to hope that the regression tests
are correct and sufficient.  Such a hope seems likely to be ill-founded,
given my experience with dir.c-related testcases in the last few months:

  Examples where the documentation was hard to parse or even just wrong:
   * 3aca58045f (git-clean.txt: do not claim we will delete files with
                   -n/--dry-run, 2019-09-17)
   * 09487f2cba (clean: avoid removing untracked files in a nested git
                   repository, 2019-09-17)
   * e86bbcf987 (clean: disambiguate the definition of -d, 2019-09-17)
  Examples where testcases were declared wrong and changed:
   * 09487f2cba (clean: avoid removing untracked files in a nested git
                   repository, 2019-09-17)
   * e86bbcf987 (clean: disambiguate the definition of -d, 2019-09-17)
   * a2b13367fe (Revert "dir.c: make 'git-status --ignored' work within
                   leading directories", 2019-12-10)
  Examples where testcases were clearly inadequate:
   * 502c386ff9 (t7300-clean: demonstrate deleting nested repo with an
                   ignored file breakage, 2019-08-25)
   * 7541cc5302 (t7300: add testcases showing failure to clean specified
                   pathspecs, 2019-09-17)
   * a5e916c745 (dir: fix off-by-one error in match_pathspec_item,
                   2019-09-17)
   * 404ebceda0 (dir: also check directories for matching pathspecs,
                   2019-09-17)
   * 09487f2cba (clean: avoid removing untracked files in a nested git
                   repository, 2019-09-17)
   * e86bbcf987 (clean: disambiguate the definition of -d, 2019-09-17)
   * 452efd11fb (t3011: demonstrate directory traversal failures,
                   2019-12-10)
   * b9670c1f5e (dir: fix checks on common prefix directory, 2019-12-19)
  Examples where "correct behavior" was unclear to everyone:
    https://lore.kernel.org/git/20190905154735.29784-1-newren@gmail.com/
  Other commits of note:
   * 902b90cf42 (clean: fix theoretical path corruption, 2019-09-17)

However, on the positive side, it does make the code much faster.  For
the following simple shell loop in an empty repository:

  for depth in $(seq 10 25)
  do
    dirs=$(for i in $(seq 1 $depth) ; do printf 'dir/' ; done)
    rm -rf dir
    mkdir -p $dirs
    >$dirs/untracked-file
    /usr/bin/time --format="$depth: %e" git status --ignored >/dev/null
  done

I saw the following timings, in seconds (note that the numbers are a
little noisy from run-to-run, but the trend is very clear with every
run):

    10: 0.03
    11: 0.05
    12: 0.08
    13: 0.19
    14: 0.29
    15: 0.50
    16: 1.05
    17: 2.11
    18: 4.11
    19: 8.60
    20: 17.55
    21: 33.87
    22: 68.71
    23: 140.05
    24: 274.45
    25: 551.15

For the above run, using strace I can look for the number of untracked
directories opened and can verify that it matches the expected
2^($depth+1)-2 (the sum of 2^1 + 2^2 + 2^3 + ... + 2^$depth).

After this fix, with strace I can verify that the number of untracked
directories that are opened drops to just $depth, and the timings all
drop to 0.00.  In fact, it isn't until a depth of 190 nested directories
that it sometimes starts reporting a time of 0.01 seconds and doesn't
consistently report 0.01 seconds until there are 240 nested directories.
The previous code would have taken
  17.55 * 2^220 / (60*60*24*365) = 9.4 * 10^59 YEARS
to have completed the 240 nested directories case.  It's not often
that you get to speed something up by a factor of 3*10^69.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-04-01 11:10:38 -07:00
Derrick Stolee 0bbd0e8b52 dir: refactor treat_directory to clarify control flow
The logic in treat_directory() is handled by a multi-case
switch statement, but this switch is very asymmetrical, as
the first two cases are simple but the third is more
complicated than the rest of the method. In fact, the third
case includes a "break" statement that leads to the block
of code outside the switch statement. That is the only way
to reach that block, as the switch handles all possible
values from directory_exists_in_index();

Extract the switch statement into a series of "if" statements.
This simplifies the trivial cases, while clarifying how to
reach the "show_other_directories" case. This is particularly
important as the "show_other_directories" case will expand
in a later change.

Helped-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-04-01 11:10:38 -07:00
Elijah Newren 2df179d3df dir: fix confusion based on variable tense
Despite having contributed several fixes in this area, I have for months
(years?) assumed that the "exclude" variable was a directive; this
caused me to think of it as a different mode we operate in and left me
confused as I tried to build up a mental model around why we'd need such
a directive.  I mostly tried to ignore it while focusing on the pieces I
was trying to understand.

Then I finally traced this variable all back to a call to is_excluded(),
meaning it was actually functioning as an adjective.  In particular, it
was a checked property ("Does this path match a rule in .gitignore?"),
rather than a mode passed in from the caller.  Change the variable name
to match the part of speech used by the function called to define it,
which will hopefully make these bits of code slightly clearer to the
next reader.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-04-01 11:10:38 -07:00
Elijah Newren 0126d1415a dir: fix broken comment
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-04-01 11:10:38 -07:00
Elijah Newren cd129eed98 dir: consolidate treat_path() and treat_one_path()
Commit 16e2cfa909 ("read_directory(): further split treat_path()",
2010-01-08) split treat_one_path() out of treat_path(), because
treat_leading_path() would not have access to a dirent but wanted to
re-use as much of treat_path() as possible.  Not re-using all of
treat_path() caused other bugs, as noted in commit b9670c1f5e ("dir:
fix checks on common prefix directory", 2019-12-19).  Finally, in commit
ad6f2157f9 ("dir: restructure in a way to avoid passing around a
struct dirent", 2020-01-16), dirents were removed from treat_path() and
other functions entirely.

Since the only reason for splitting these functions was the lack of a
dirent -- which no longer applies to either function -- and since the
split caused problems in the past resulting in us not using
treat_one_path() separately anymore, just undo the split.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-04-01 11:10:38 -07:00
Elijah Newren 446f46d8c7 dir: fix simple typo in comment
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-04-01 11:10:38 -07:00
Junio C Hamano f4d7dfce4d Merge branch 'ds/sparse-add'
"git sparse-checkout" learned a new "add" subcommand.

* ds/sparse-add:
  sparse-checkout: allow one-character directories in cone mode
  sparse-checkout: work with Windows paths
  sparse-checkout: create 'add' subcommand
  sparse-checkout: extract pattern update from 'set' subcommand
  sparse-checkout: extract add_patterns_from_input()
2020-03-05 10:43:02 -08:00
Derrick Stolee 6c11c6a124 sparse-checkout: allow one-character directories in cone mode
In 9e6d3e64 (sparse-checkout: detect short patterns, 2020-01-24), a
condition on the minimum length of a cone-mode pattern was introduced.
However, this condition was off-by-one.

If we have a directory with a single character, say "b", then the
command

	git sparse-checkout set b

will correctly add the pattern "/b/" to the sparse-checkout file. When
this is interpeted in dir.c, the pattern is "/b" with the
PATTERN_FLAG_MUSTBEDIR flag. This string has length two, which satisfies
our inclusive inequality (<= 2).

The reason for this inequality is that we will start to read the pattern
string character-by-character using three char pointers: prev, cur,
next. In particular, next is set to the current pattern plus two. The
mistake was that next will still be a valid pointer when the pattern
length is two, since the string is null-terminated.

Make this inequality strict so these patterns work.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-02-20 14:43:36 -08:00
Junio C Hamano 78e67cda42 Merge branch 'mt/use-passed-repo-more-in-funcs'
Some codepaths were given a repository instance as a parameter to
work in the repository, but passed the_repository instance to its
callees, which has been cleaned up (somewhat).

* mt/use-passed-repo-more-in-funcs:
  sha1-file: allow check_object_signature() to handle any repo
  sha1-file: pass git_hash_algo to hash_object_file()
  sha1-file: pass git_hash_algo to write_object_file_prepare()
  streaming: allow open_istream() to handle any repo
  pack-check: use given repo's hash_algo at verify_packfile()
  cache-tree: use given repo's hash_algo at verify_one()
  diff: make diff_populate_filespec() honor its repo argument
2020-02-14 12:54:22 -08:00
Junio C Hamano 433b8aac2e Merge branch 'ds/sparse-checkout-harden'
Some rough edges in the sparse-checkout feature, especially around
the cone mode, have been cleaned up.

* ds/sparse-checkout-harden:
  sparse-checkout: fix cone mode behavior mismatch
  sparse-checkout: improve docs around 'set' in cone mode
  sparse-checkout: escape all glob characters on write
  sparse-checkout: use C-style quotes in 'list' subcommand
  sparse-checkout: unquote C-style strings over --stdin
  sparse-checkout: write escaped patterns in cone mode
  sparse-checkout: properly match escaped characters
  sparse-checkout: warn on globs in cone patterns
  sparse-checkout: detect short patterns
  sparse-checkout: cone mode does not recognize "**"
  sparse-checkout: fix documentation typo for core.sparseCheckoutCone
  clone: fix --sparse option with URLs
  sparse-checkout: create leading directories
  t1091: improve here-docs
  t1091: use check_files to reduce boilerplate
2020-02-14 12:54:22 -08:00
Derrick Stolee 4f52c2ce6c sparse-checkout: properly match escaped characters
In cone mode, the sparse-checkout feature uses hashset containment
queries to match paths. Make this algorithm respect escaped asterisk
(*) and backslash (\) characters.

Create dup_and_filter_pattern() method to convert a pattern by
removing escape characters and dropping an optional "/*" at the end.
This method is available in dir.h as we will use it in
builtin/sparse-checkout.c in a later change.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-01-31 13:05:29 -08:00
Derrick Stolee 9abc60f801 sparse-checkout: warn on globs in cone patterns
In cone mode, the sparse-checkout commmand will write patterns that
allow faster pattern matching. This matching only works if the patterns
in the sparse-checkout file are those written by that command. Users
can edit the sparse-checkout file and create patterns that cause the
cone mode matching to fail.

The cone mode patterns may end in "/*" but otherwise an un-escaped
asterisk or other glob character is invalid. Add checks to disable
cone mode when seeing these values.

A later change will properly handle escaped globs.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-01-31 13:05:29 -08:00
Matheus Tavares 2dcde20e1c sha1-file: pass git_hash_algo to hash_object_file()
Allow hash_object_file() to work on arbitrary repos by introducing a
git_hash_algo parameter. Change callers which have a struct repository
pointer in their scope to pass on the git_hash_algo from the said repo.
For all other callers, pass on the_hash_algo, which was already being
used internally at hash_object_file(). This functionality will be used
in the following patch to make check_object_signature() be able to work
on arbitrary repos (which, in turn, will be used to fix an
inconsistency at object.c:parse_object()).

Signed-off-by: Matheus Tavares <matheus.bernardino@usp.br>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-01-31 10:45:39 -08:00
Derrick Stolee 9e6d3e6417 sparse-checkout: detect short patterns
In cone mode, the shortest pattern the sparse-checkout command will
write into the sparse-checkout file is "/*". This is handled carefully
in add_pattern_to_hashsets(), so warn if any other pattern is this
short. This will assist future pattern checks by allowing us to assume
there are at least three characters in the pattern.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-01-24 13:26:54 -08:00
Derrick Stolee 41de0c6fbc sparse-checkout: cone mode does not recognize "**"
When core.sparseCheckoutCone is enabled, the 'git sparse-checkout set'
command creates a restricted set of possible patterns that are used
by a custom algorithm to quickly match those patterns.

If a user manually edits the sparse-checkout file, then they could
create patterns that do not match these expectations. The cone-mode
matching algorithm can return incorrect results. The solution is to
detect these incorrect patterns, warn that we do not recognize them,
and revert to the standard algorithm.

Check each pattern for the "**" substring, and revert to the old
logic if seen. While technically a "/<dir>/**" pattern matches
the meaning of "/<dir>/", it is not one that would be written by
the sparse-checkout builtin in cone mode. Attempting to accept that
pattern change complicates the logic and instead we punt and do
not accept any instance of "**".

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-01-24 13:26:54 -08:00
Jeff King 0cbb60574e dir: point treat_leading_path() warning to the right place
Commit 777b420347 (dir: synchronize treat_leading_path() and
read_directory_recursive(), 2019-12-19) tried to add two warning
comments in those functions, pointing at each other. But the one in
treat_leading_path() just points at itself.

Let's fix that. Since the comment also redirects the reader for more
details to "the commit that added this warning", and since we're now
modifying the warning (creating a new commit without those details),
let's mention the actual commit id.

Signed-off-by: Jeff King <peff@peff.net>
Reviewed-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-01-16 12:56:13 -08:00
Jeff King ad6f2157f9 dir: restructure in a way to avoid passing around a struct dirent
Restructure the code slightly to avoid passing around a struct dirent
anywhere, which also enables us to avoid trying to manufacture one.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-01-16 12:56:13 -08:00