Add t/helper/test-lazy-init-name-hash.c test code
to demonstrate performance times for lazy_init_name_hash()
using the original single-threaded and the new multi-threaded
code paths.
Includes a --dump option to dump the created hashmaps to
stdout. You can use this to run both code paths and
confirm that they generate the same hashmaps.
Includes a --analyze option to analyze performance of both
code paths over a range of index sizes to help you find a
lower bound for the LAZY_THREAD_COST in name-hash.c.
For example, passing "-a 4000" will set "istate.cache_nr"
to 4000 and then try the multi-threaded code -- probably
giving 2 threads with 2000 entries each. It will then
run both the single-threaded (1x4000) and the multi-threaded
(2x2000) and compare the times. It will then repeat the
test with 8000, 12000, and etc. so that you can see the
cross over.
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Code clean-up.
* jk/pack-name-cleanups:
index-pack: make pointer-alias fallbacks safer
replace snprintf with odb_pack_name()
odb_pack_keep(): stop generating keepfile name
sha1_file.c: make pack-name helper globally accessible
move odb_* declarations out of git-compat-util.h
The prefix_filename() function returns a pointer to static
storage, which makes it easy to use dangerously. We already
fixed one buggy caller in hash-object recently, and the
calls in apply.c are suspicious (I didn't dig in enough to
confirm that there is a bug, but we call the function once
in apply_all_patches() and then again indirectly from
parse_chunk()).
Let's make it harder to get wrong by allocating the return
value. For simplicity, we'll do this even when the prefix is
empty (and we could just return the original file pointer).
That will cause us to allocate sometimes when we wouldn't
otherwise need to, but this function isn't called in
performance critical code-paths (and it already _might_
allocate on any given call, so a caller that cares about
performance is questionable anyway).
The downside is that the callers need to remember to free()
the result to avoid leaking. Most of them already used
xstrdup() on the result, so we know they are OK. The
remainder have been converted to use free() as appropriate.
I considered retaining a prefix_filename_unsafe() for cases
where we know the static lifetime is OK (and handling the
cleanup is awkward). This is only a handful of cases,
though, and it's not worth the mental energy in worrying
about whether the "unsafe" variant is OK to use in any
situation.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This function takes the prefix as a ptr/len pair, but in
every caller the length is exactly strlen(ptr). Let's
simplify the interface and just take the string. This saves
callers specifying it (and in some cases handling a NULL
prefix).
In a handful of cases we had the length already without
calling strlen, so this is technically slower. But it's not
likely to matter (after all, if the prefix is non-empty
we'll allocate and copy it into a buffer anyway).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This is a public function, so we should make its
documentation available near the declaration.
While we're at it, we can give a few details about how it
works.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The start-up sequence of "git" needs to figure out some configured
settings before it finds and set itself up in the location of the
repository and was quite messy due to its "chicken-and-egg" nature.
The code has been restructured.
* js/early-config:
setup.c: mention unresolved problems
t1309: document cases where we would want early config not to die()
setup_git_directory_gently_1(): avoid die()ing
t1309: test read_early_config()
read_early_config(): really discover .git/
read_early_config(): avoid .git/config hack when unneeded
setup: make read_early_config() reusable
setup: introduce the discover_git_directory() function
setup_git_directory_1(): avoid changing global state
setup: prepare setup_discovered_git_dir() for the root directory
setup_git_directory(): use is_dir_sep() helper
t7006: replace dubious test
Our source code has used the SHA1_HEADER cpp macro after "#include"
in the C code to switch among the SHA-1 implementations. Instead,
list the exact header file names and switch among implementations
using "#ifdef BLK_SHA1/#include "block-sha1/sha1.h"/.../#endif";
this helps some IDE tools.
* bc/sha1-header-selection-with-cpp-macros:
hash.h: move SHA-1 implementation selection into a header file
The experimental "split index" feature has gained a few
configuration variables to make it easier to use.
* cc/split-index-config: (22 commits)
Documentation/git-update-index: explain splitIndex.*
Documentation/config: add splitIndex.sharedIndexExpire
read-cache: use freshen_shared_index() in read_index_from()
read-cache: refactor read_index_from()
t1700: test shared index file expiration
read-cache: unlink old sharedindex files
config: add git_config_get_expiry() from gc.c
read-cache: touch shared index files when used
sha1_file: make check_and_freshen_file() non static
Documentation/config: add splitIndex.maxPercentChange
t1700: add tests for splitIndex.maxPercentChange
read-cache: regenerate shared index if necessary
config: add git_config_get_max_percent_split_change()
Documentation/git-update-index: talk about core.splitIndex config var
Documentation/config: add information for core.splitIndex
t1700: add tests for core.splitIndex
update-index: warn in case of split-index incoherency
read-cache: add and then use tweak_split_index()
split-index: add {add,remove}_split_index() functions
config: add git_config_get_split_index()
...
In a future patch child processes which act on submodules need a little
more context about the original command that was invoked. This patch
teaches git to use the prefix stored in `GIT_INTERNAL_TOPLEVEL_PREFIX`
instead of the prefix that was potentally found during the git directory
setup process.
Signed-off-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The odb_pack_keep() function generates the name of a .keep
file and opens it. This has two problems:
1. It requires a fixed-size buffer to create the filename
and doesn't notice when the result is truncated.
2. Of the two callers, one sometimes wants to open a
filename it already has, which makes things awkward (it
has to do so manually, and skips the leading-directory
creation).
Instead, let's have odb_pack_keep() just open the file.
Generating the name isn't hard, and a future patch will
switch callers over to odb_pack_name() anyway.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We provide sha1_pack_name() and sha1_pack_index_name(), but
the more generic form (which takes its own strbuf and an
arbitrary extension) is only used to implement the other
two. Let's make it available, but clean up a few things:
1. Name it odb_pack_name(), as the original
sha1_get_pack_name() is long but not all that
descriptive.
2. Switch the strbuf argument to the beginning, so that it
matches similar path-building functions like
git_path_buf().
3. Clean up the out-dated docstring and move it to the
public declaration.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
These functions were originally conceived as wrapper
functions similar to xmkstemp(). They were later moved by
463db9b10 (wrapper: move odb_* to environment.c,
2010-11-06). The more appropriate place for a declaration is
in cache.h.
While we're at it, let's add some basic docstrings.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Many developers use functionality in their editors that allows for quick
syntax checks, including warning about questionable constructs. This
functionality allows rapid development with fewer errors. However, such
functionality generally does not allow the specification of
project-specific defines or command-line options.
Since the SHA1_HEADER include is not defined in such a case,
developers see spurious errors when using these tools. Furthermore,
there are known implementations of "cc" whose '#include' is unhappy
with this construct.
Instead of using SHA1_HEADER, create a hash.h header and use #if
and #elif to select the desired header. Have the Makefile pass an
appropriate option to help the header select the right implementation to
use.
[jc: make BLK_SHA1 the fallback default as discussed on list,
e.g. <20170314201424.vccij5z2ortq4a4o@sigill.intra.peff.net>; also
remove SHA1_HEADER and SHA1_HEADER_SQ that are no longer used].
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Reviewed-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"git branch @" created refs/heads/@ as a branch, and in general the
code that handled @{-1} and @{upstream} was a bit too loose in
disambiguating.
* jk/interpret-branch-name:
checkout: restrict @-expansions when finding branch
strbuf_check_ref_format(): expand only local branches
branch: restrict @-expansions when deleting
t3204: test git-branch @-expansion corner cases
interpret_branch_name: allow callers to restrict expansions
strbuf_branchname: add docstring
strbuf_branchname: drop return value
interpret_branch_name: move docstring to header file
interpret_branch_name(): handle auto-namelen for @{-1}
The pager configuration needs to be read early, possibly before
discovering any .git/ directory.
Let's not hide this function in pager.c, but make it available to other
callers.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We modified the setup_git_directory_gently_1() function earlier to make
it possible to discover the GIT_DIR without changing global state.
However, it is still a bit cumbersome to use if you only need to figure
out the (possibly absolute) path of the .git/ directory. Let's just
provide a convenient wrapper function with an easier signature that
*just* discovers the .git/ directory.
We will use it in a subsequent patch to fix the early config.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We already have xdg_config_home to format paths relative to
XDG_CONFIG_HOME. Let's provide a similar function xdg_cache_home to do
the same for paths relative to XDG_CACHE_HOME.
Signed-off-by: Devin Lehmacher <lehmacdj@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Git v2.12 was shipped with an embarrassing breakage where various
operations that verify paths given from the user stopped dying when
seeing an issue, and instead later triggering segfault.
* js/realpath-pathdup-fix:
real_pathdup(): fix callsites that wanted it to die on error
t1501: demonstrate NULL pointer access with invalid GIT_WORK_TREE
The "parse_config_key()" API function has been cleaned up.
* jk/parse-config-key-cleanup:
parse_hide_refs_config: tell parse_config_key we don't want a subsection
parse_config_key: allow matching single-level config
parse_config_key: use skip_prefix instead of starts_with
In 4ac9006f83 (real_path: have callers use real_pathdup and
strbuf_realpath, 2016-12-12), we changed the xstrdup(real_path())
pattern to use real_pathdup() directly.
The problem with this change is that real_path() calls
strbuf_realpath() with die_on_error = 1 while real_pathdup() calls
it with die_on_error = 0. Meaning that in cases where real_path()
causes Git to die() with an error message, real_pathdup() is silent
and returns NULL instead.
The callers, however, are ill-prepared for that change, as they expect
the return value to be non-NULL (and otherwise the function died
with an appropriate error message).
Fix this by extending real_pathdup()'s signature to accept the
die_on_error flag and simply pass it through to strbuf_realpath(),
and then adjust all callers after a careful audit whether they would
handle NULLs well.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The interpret_branch_name() function converts names like
@{-1} and @{upstream} into branch names. The expanded ref
names are not fully qualified, and may be outside of the
refs/heads/ namespace (e.g., "@" expands to "HEAD", and
"@{upstream}" is likely to be in "refs/remotes/").
This is OK for callers like dwim_ref() which are primarily
interested in resolving the resulting name, no matter where
it is. But callers like "git branch" treat the result as a
branch name in refs/heads/. When we expand to a ref outside
that namespace, the results are very confusing (e.g., "git
branch @" tries to create refs/heads/HEAD, which is
nonsense).
Callers can't know from the returned string how the
expansion happened (e.g., did the user really ask for a
branch named "HEAD", or did we do a bogus expansion?). One
fix would be to return some out-parameters describing the
types of expansion that occurred. This has the benefit that
the caller can generate precise error messages ("I
understood @{upstream} to mean origin/master, but that is a
remote tracking branch, so you cannot create it as a local
name").
However, out-parameters make the function interface somewhat
cumbersome. Instead, let's do the opposite: let the caller
tell us which elements to expand. That's easier to pass in,
and none of the callers give more precise error messages
than "@{upstream} isn't a valid branch name" anyway (which
should be sufficient).
The strbuf_branchname() function needs a similar parameter,
as most of the callers access interpret_branch_name()
through it.
We can break the callers down into two groups:
1. Callers that are happy with any kind of ref in the
result. We pass "0" here, so they continue to work
without restrictions. This includes merge_name(),
the reflog handling in add_pending_object_with_path(),
and substitute_branch_name(). This last is what powers
dwim_ref().
2. Callers that have funny corner cases (mostly in
git-branch and git-checkout). These need to make use of
the new parameter, but I've left them as "0" in this
patch, and will address them individually in follow-on
patches.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We generally put docstrings with function declarations,
because it's the callers who need to know how the function
works. Let's do so for interpret_branch_name().
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This function will be used in a following commit to get the expiration
time of the shared index files from the config, and it is generic
enough to be put in "config.c".
Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This function will be used in a commit soon, so let's make
it available globally.
Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This new function will be used in a following commit to get the
value of the "splitIndex.maxPercentChange" config variable.
Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This new function will be used in a following commit to know
if we want to use the split index feature or not.
Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The last caller of git_mkstemp() was removed in commit 6fec0a89
("verify_signed_buffer: use tempfile object", 16-06-2016). Since
the introduction of the 'tempfile' APIs, along with git_mkstemp_mode,
it is unlikely that new callers will materialize. Remove the dead
code.
Signed-off-by: Ramsay Jones <ramsay@ramsayjones.plus.com>
Reviewed-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Deletion of a branch "foo/bar" could remove .git/refs/heads/foo
once there no longer is any other branch whose name begins with
"foo/", but we didn't do so so far. Now we do.
* mh/ref-remove-empty-directory: (23 commits)
files_transaction_commit(): clean up empty directories
try_remove_empty_parents(): teach to remove parents of reflogs, too
try_remove_empty_parents(): don't trash argument contents
try_remove_empty_parents(): rename parameter "name" -> "refname"
delete_ref_loose(): inline function
delete_ref_loose(): derive loose reference path from lock
log_ref_write_1(): inline function
log_ref_setup(): manage the name of the reflog file internally
log_ref_write_1(): don't depend on logfile argument
log_ref_setup(): pass the open file descriptor back to the caller
log_ref_setup(): improve robustness against races
log_ref_setup(): separate code for create vs non-create
log_ref_write(): inline function
rename_tmp_log(): improve error reporting
rename_tmp_log(): use raceproof_create_file()
lock_ref_sha1_basic(): use raceproof_create_file()
lock_ref_sha1_basic(): inline constant
raceproof_create_file(): new function
safe_create_leading_directories(): set errno on SCLD_EXISTS
safe_create_leading_directories_const(): preserve errno
...
The parse_config_key() function was introduced to make it
easier to match "section.subsection.key" variables. It also
handles the simpler "section.key", and the caller is
responsible for distinguishing the two from its
out-parameters.
Most callers who _only_ want "section.key" would just use a
strcmp(var, "section.key"), since there is no parsing
required. However, they may still use parse_config_key() if
their "section" variable isn't a constant (an example of
this is in parse_hide_refs_config).
Using the parse_config_key is a bit clunky, though:
const char *subsection;
int subsection_len;
const char *key;
if (!parse_config_key(var, section, &subsection, &subsection_len, &key) &&
!subsection) {
/* matched! */
}
Instead, let's treat a NULL subsection as an indication that
the caller does not expect one. That lets us write:
const char *key;
if (!parse_config_key(var, section, NULL, NULL, &key)) {
/* matched! */
}
Existing callers should be unaffected, as passing a NULL
subsection would currently segfault.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Convert each_loose_object_fn and each_packed_object_fn to take a pointer
to struct object_id. Update the various callbacks. Convert several
40-based constants to use GIT_SHA1_HEXSZ.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
There are places in the code where we would like to provide a struct
object_id *, yet read the hash directly from the pack. Provide an
nth_packed_object_oid function that is similar to the
nth_packed_object_sha1 function.
In order to avoid a potentially invalid cast, nth_packed_object_oid
provides a variable into which to store the value, which it returns on
success; on error, it returns NULL, as nth_packed_object_sha1 does.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Introduce a function, parse_oid_hex, which parses a hexadecimal object
ID and if successful, sets a pointer to just beyond the last character.
This allows for simpler, more robust parsing without needing to
hard-code integer values throughout the codebase.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The "core.logAllRefUpdates" that used to be boolean has been
enhanced to take 'always' as well, to record ref updates to refs
other than the ones that are expected to be updated (i.e. branches,
remote-tracking branches and notes).
* cw/log-updates-for-all-refs-really:
doc: add note about ignoring '--no-create-reflog'
update-ref: add test cases for bare repository
refs: add option core.logAllRefUpdates = always
config: add markup to core.logAllRefUpdates doc
When a submodule "A", which has another submodule "B" nested within
it, is "absorbed" into the top-level superproject, the inner
submodule "B" used to be left in a strange state. The logic to
adjust the .git pointers in these submodules has been corrected.
* sb/submodule-recursive-absorb:
submodule absorbing: fix worktree/gitdir pointers recursively for non-moves
cache.h: expose the dying procedure for reading gitlinks
setup: add gentle version of resolve_git_dir
When core.logallrefupdates is true, we only create a new reflog for refs
that are under certain well-known hierarchies. The reason is that we
know that some hierarchies (like refs/tags) are not meant to change, and
that unknown hierarchies might not want reflogs at all (e.g., a
hypothetical refs/foo might be meant to change often and drop old
history immediately).
However, sometimes it is useful to override this decision and simply log
for all refs, because the safety and audit trail is more important than
the performance implications of keeping the log around.
This patch introduces a new "always" mode for the core.logallrefupdates
option which will log updates to everything under refs/, regardless
where in the hierarchy it is (we still will not log things like
ORIG_HEAD and FETCH_HEAD, which are known to be transient).
Based-on-patch-by: Jeff King <peff@peff.net>
Signed-off-by: Cornelius Weig <cornelius.weig@tngtech.com>
Reviewed-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add a function that returns a buffer containing the absolute path of its
argument and a semantic patch for its intended use. It avoids an extra
string copy to a static buffer.
Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In a later patch we want to react to only a subset of errors, defaulting
the rest to die as usual. Separate the block that takes care of dying
into its own function so we have easy access to it.
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This follows a93bedada (setup: add gentle version of read_gitfile,
2015-06-09), and assumes the same reasoning. resolve_git_dir is unsuited
for speculative calls, so we want to use the gentle version to find out
about potential errors.
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Do this by moving the existing documentation from
read-cache.c to cache.h.
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Code clean-up in the pathspec API.
* bw/pathspec-cleanup:
pathspec: rename prefix_pathspec to init_pathspec_item
pathspec: small readability changes
pathspec: create strip submodule slash helpers
pathspec: create parse_element_magic helper
pathspec: create parse_long_magic function
pathspec: create parse_short_magic function
pathspec: factor global magic into its own function
pathspec: simpler logic to prefix original pathspec elements
pathspec: always show mnemonic and name in unsupported_magic
pathspec: remove unused variable from unsupported_magic
pathspec: copy and free owned memory
pathspec: remove the deprecated get_pathspec function
ls-tree: convert show_recursive to use the pathspec struct interface
dir: convert fill_directory to use the pathspec struct interface
dir: remove struct path_simplify
mv: remove use of deprecated 'get_pathspec()'
"git grep" has been taught to optionally recurse into submodules.
* bw/grep-recurse-submodules:
grep: search history of moved submodules
grep: enable recurse-submodules to work on <tree> objects
grep: optionally recurse into submodules
grep: add submodules as a grep source type
submodules: load gitmodules file from commit sha1
submodules: add helper to determine if a submodule is initialized
submodules: add helper to determine if a submodule is populated
real_path: canonicalize directory separators in root parts
real_path: have callers use real_pathdup and strbuf_realpath
real_path: create real_pathdup
real_path: convert real_path_internal to strbuf_realpath
real_path: resolve symlinks by hand
It's surprisingly hard to ask the sha1_file code to open a
_specific_ incarnation of a loose object. Most of the
functions take a sha1, and loop over the various object
types (packed versus loose) and locations (local versus
alternates) at a low level.
However, some tools like fsck need to look at a specific
file. This patch gives them a function they can use to open
the loose object at a given path.
The implementation unfortunately ends up repeating bits of
related functions, but there's not a good way around it
without some major refactoring of the whole sha1_file stack.
We need to mmap the specific file, then partially read the
zlib stream to know whether we're streaming or not, and then
finally either stream it or copy the data to a buffer.
We can do that by assembling some of the more arcane
internal sha1_file functions, but we end up having to
essentially reimplement unpack_sha1_file(), along with the
streaming bits of check_sha1_signature().
Still, most of the ugliness is contained in the new
function, and the interface is clean enough that it may be
reusable (though it seems unlikely anything but git-fsck
would care about opening a specific file).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Improve constness of the index_state parameter to the
'read_blob_data_from_index' function.
Signed-off-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The codeflow of setting NOATIME and CLOEXEC on file descriptors Git
opens has been simplified.
We may want to drop the tip one, but we'll see.
* jc/git-open-cloexec:
sha1_file: stop opening files with O_NOATIME
git_open_cloexec(): use fcntl(2) w/ FD_CLOEXEC fallback
git_open(): untangle possible NOATIME and CLOEXEC interactions
Now that all callers of the old 'get_pathspec' interface have been
migrated to use the new pathspec struct interface it can be removed
from the codebase.
Since there are no more users of the '_raw' field in the pathspec struct
it can also be removed. This patch also removes the old functionality
of modifying the const char **argv array that was passed into
parse_pathspec. Instead the constructed 'match' string (which is a
pathspec element with the prefix prepended) is only stored in its
corresponding pathspec_item entry.
Signed-off-by: Brandon Williams <bmwill@google.com>
Reviewed-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add a function that tries to create a file and any containing
directories in a way that is robust against races with other processes
that might be cleaning up empty directories at the same time.
The actual file creation is done by a callback function, which, if it
fails, should set errno to EISDIR or ENOENT according to the convention
of open(). raceproof_create_file() detects such failures, and
respectively either tries to delete empty directories that might be in
the way of the file or tries to create the containing directories. Then
it retries the callback function.
This function is not yet used.
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Reviewed-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The exit path for SCLD_EXISTS wasn't setting errno, which some callers
use to generate error messages for the user. Fix the problem and
document that the function sets errno correctly to help avoid similar
regressions in the future.
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Reviewed-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
teach submodules to load a '.gitmodules' file from a commit sha1. This
enables the population of the submodule_cache to be based on the state
of the '.gitmodules' file from a particular commit.
Signed-off-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Create real_pathdup which returns a caller owned string of the resolved
realpath based on the provide path.
Signed-off-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Change the name of real_path_internal to strbuf_realpath. In addition
push the static strbuf up to its callers and instead take as a
parameter a pointer to a strbuf to use for the final result.
This change makes strbuf_realpath reentrant.
Signed-off-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
There are three codepaths that use a variable whose name is
pack_compression_level to affect how objects and deltas sent to a
packfile is compressed. Unlike zlib_compression_level that controls
the loose object compression, however, this variable was static to
each of these codepaths. Two of them read the pack.compression
configuration variable, using core.compression as the default, and
one of them also allowed overriding it from the command line.
The other codepath in bulk-checkin did not pay any attention to the
configuration.
Unify the configuration parsing to git_default_config(), where we
implement the parsing of core.loosecompression and core.compression
and make the former override the latter, by moving code to parse
pack.compression and also allow core.compression to give default to
this variable.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When we open object files, we try to do so with O_NOATIME.
This dates back to 144bde78e9 (Use O_NOATIME when opening
the sha1 files., 2005-04-23), which is an optimization to
avoid creating a bunch of dirty inodes when we're accessing
many objects. But a few things have changed since then:
1. In June 2005, git learned about packfiles, which means
we would do a lot fewer atime updates (rather than one
per object access, we'd generally get one per packfile).
2. In late 2006, Linux learned about "relatime", which is
generally the default on modern installs. So
performance around atimes updates is a non-issue there
these days.
All the world isn't Linux, but as it turns out, Linux
is the only platform to implement O_NOATIME in the
first place.
So it's very unlikely that this code is helping anybody
these days.
Helped-by: Jeff King <peff@peff.net>
[jc: took idea and log message from peff]
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Git generally does not explicitly close file descriptors that were
open in the parent process when spawning a child process, but most
of the time the child does not want to access them. As Windows does
not allow removing or renaming a file that has a file descriptor
open, a slow-to-exit child can even break the parent process by
holding onto them. Use O_CLOEXEC flag to open files in various
codepaths.
* ls/git-open-cloexec:
read-cache: make sure file handles are not inherited by child processes
sha1_file: open window into packfiles with O_CLOEXEC
sha1_file: rename git_open_noatime() to git_open()
When fetching from a remote that has many tags that are irrelevant
to branches we are following, we used to waste way too many cycles
when checking if the object pointed at by a tag (that we are not
going to fetch!) exists in our repository too carefully.
* jk/fetch-quick-tag-following:
fetch: use "quick" has_sha1_file for tag following
The way we structured the fallback/retry mechanism for opening with
O_NOATIME and O_CLOEXEC meant that if we failed due to lack of
support to open the file with O_NOATIME option (i.e. EINVAL), we
would still try to drop O_CLOEXEC first and retry, and then drop
O_NOATIME. A platform on which O_NOATIME is defined in the header
without support from the kernel wouldn't have a chance to open with
O_CLOEXEC option due to this code structure.
Arguably, O_CLOEXEC is more important than O_NOATIME, as the latter
is mostly about performance, while the former can affect correctness.
Instead use O_CLOEXEC to open the file, and then use fcntl(2) to set
O_NOATIME on the resulting file descriptor. open(2) itself does not
cause atime to be updated according to Linus [*1*].
The helper to do the former can be usable in the codepath in
ce_compare_data() that was recently added to open a file descriptor
with O_CLOEXEC; use it while we are at it.
*1* <CA+55aFw83E+zOd+z5h-CA-3NhrLjVr-anL6pubrSWttYx3zu8g@mail.gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Update "git diff --no-index" codepath not to try to peek into .git/
directory that happens to be under the current directory, when we
know we are operating outside any repository.
* jk/no-looking-at-dotgit-outside-repo:
diff: handle sha1 abbreviations outside of repository
diff_aligned_abbrev: use "struct oid"
diff_unique_abbrev: rename to diff_aligned_abbrev
find_unique_abbrev: use 4-buffer ring
test-*-cache-tree: setup git dir
read info/{attributes,exclude} only when in repository
Updates the way approximate count of total objects is computed
while attempting to come up with a unique abbreviated object name,
which in turn needs to estimate how many hexdigits are necessary to
ensure uniqueness.
* jk/abbrev-auto:
find_unique_abbrev: move logic out of get_short_sha1()
Allow the default abbreviation length, which has historically been
7, to scale as the repository grows. The logic suggests to use 12
hexdigits for the Linux kernel, and 9 to 10 for Git itself.
* lt/abbrev-auto:
abbrev: auto size the default abbreviation
abbrev: prepare for new world order
abbrev: add FALLBACK_DEFAULT_ABBREV to prepare for auto sizing
Some code paths want to format multiple abbreviated sha1s in
the same output line. Because we use a single static buffer
for our return value, they have to either break their output
into several calls or allocate their own arrays and use
find_unique_abbrev_r().
Intead, let's mimic sha1_to_hex() and use a ring of several
buffers, so that the return value stays valid through
multiple calls. This shortens some of the callers, and makes
it harder to for them to make a silly mistake.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When fetching from a remote that has many tags that are irrelevant
to branches we are following, we used to waste way too many cycles
when checking if the object pointed at by a tag (that we are not
going to fetch!) exists in our repository too carefully.
* jk/fetch-quick-tag-following:
fetch: use "quick" has_sha1_file for tag following
"git ls-files" learned "--recurse-submodules" option that can be
used to get a listing of tracked files across submodules (i.e. this
only works with "--cached" option, not for listing untracked or
ignored files). This would be a useful tool to sit on the upstream
side of a pipe that is read with xargs to work on all working tree
files from the top-level superproject.
* bw/ls-files-recurse-submodules:
ls-files: add pathspec matching for submodules
ls-files: pass through safe options for --recurse-submodules
ls-files: optionally recurse into submodules
git: make super-prefix option
This function is meant to be used when reading from files in the
object store, and the original objective was to avoid smudging atime
of loose object files too often, hence its name. Because we'll be
extending its role in the next commit to also arrange the file
descriptors they return auto-closed in the child processes, rename
it to lose "noatime" part that is too specific.
Signed-off-by: Lars Schneider <larsxschneider@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Codepaths involved in interacting alternate object store have
been cleaned up.
* jk/alt-odb-cleanup:
alternates: use fspathcmp to detect duplicates
sha1_file: always allow relative paths to alternates
count-objects: report alternates via verbose mode
fill_sha1_file: write into a strbuf
alternates: store scratch buffer as strbuf
fill_sha1_file: write "boring" characters
alternates: use a separate scratch space
alternates: encapsulate alt->base munging
alternates: provide helper for allocating alternate
alternates: provide helper for adding to alternates list
link_alt_odb_entry: refactor string handling
link_alt_odb_entry: handle normalize_path errors
t5613: clarify "too deep" recursion tests
t5613: do not chdir in main process
t5613: whitespace/style cleanups
t5613: use test_must_fail
t5613: drop test_valid_repo function
t5613: drop reachable_via function
In order for the receiving end of "git push" to inspect the
received history and decide to reject the push, the objects sent
from the sending end need to be made available to the hook and
the mechanism for the connectivity check, and this was done
traditionally by storing the objects in the receiving repository
and letting "git gc" to expire it. Instead, store the newly
received objects in a temporary area, and make them available by
reusing the alternate object store mechanism to them only while we
decide if we accept the check, and once we decide, either migrate
them to the repository or purge them immediately.
* jk/quarantine-received-objects:
tmp-objdir: do not migrate files starting with '.'
tmp-objdir: put quarantine information in the environment
receive-pack: quarantine objects until pre-receive accepts
tmp-objdir: introduce API for temporary object directories
check_connected: accept an env argument
When we auto-follow tags in a fetch, we look at all of the
tags advertised by the remote and fetch ones where we don't
already have the tag, but we do have the object it peels to.
This involves a lot of calls to has_sha1_file(), some of
which we can reasonably expect to fail. Since 45e8a74
(has_sha1_file: re-check pack directory before giving up,
2013-08-30), this may cause many calls to
reprepare_packed_git(), which is potentially expensive.
This has gone unnoticed for several years because it
requires a fairly unique setup to matter:
1. You need to have a lot of packs on the client side to
make reprepare_packed_git() expensive (the most
expensive part is finding duplicates in an unsorted
list, which is currently quadratic).
2. You need a large number of tag refs on the server side
that are candidates for auto-following (i.e., that the
client doesn't have). Each one triggers a re-read of
the pack directory.
3. Under normal circumstances, the client would
auto-follow those tags and after one large fetch, (2)
would no longer be true. But if those tags point to
history which is disconnected from what the client
otherwise fetches, then it will never auto-follow, and
those candidates will impact it on every fetch.
So when all three are true, each fetch pays an extra
O(nr_tags * nr_packs^2) cost, mostly in string comparisons
on the pack names. This was exacerbated by 47bf4b0
(prepare_packed_git_one: refactor duplicate-pack check,
2014-06-30) which uses a slightly more expensive string
check, under the assumption that the duplicate check doesn't
happen very often (and it shouldn't; the real problem here
is how often we are calling reprepare_packed_git()).
This patch teaches fetch to use HAS_SHA1_QUICK to sacrifice
accuracy for speed, in cases where we might be racy with a
simultaneous repack. This is similar to the fix in 0eeb077
(index-pack: avoid excessive re-reading of pack directory,
2015-06-09). As with that case, it's OK for has_sha1_file()
occasionally say "no I don't have it" when we do, because
the worst case is not a corruption, but simply that we may
fail to auto-follow a tag that points to it.
Here are results from the included perf script, which sets
up a situation similar to the one described above:
Test HEAD^ HEAD
----------------------------------------------------------
5550.4: fetch 11.21(10.42+0.78) 0.08(0.04+0.02) -99.3%
Reported-by: Vegard Nossum <vegard.nossum@oracle.com>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"git pack-objects" in a repository with many packfiles used to
spend a lot of time looking for/at objects in them; the accesses to
the packfiles are now optimized by checking the most-recently-used
packfile first.
* jk/pack-objects-optim-mru:
pack-objects: use mru list when iterating over packs
pack-objects: break delta cycles before delta-search phase
sha1_file: make packed_object_info public
provide an initializer for "struct object_info"
The presence of the GIT_QUARANTINE_PATH variable lets any
called programs know that they're operating in a temporary
object directory (and where that directory is).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We pre-size the scratch buffer to hold a loose object
filename of the form "xx/yyyy...", which leads to allocation
code that is hard to verify. We have to use some magic
numbers during the initial allocation, and then writers must
blindly assume that the buffer is big enough. Using a strbuf
makes it more clear that we cannot overflow.
Unfortunately, we do still need some magic numbers to grow
our strbuf before calling fill_sha1_path(), but the strbuf
growth is much closer to the point of use. This makes it
easier to see that it's correct, and opens the possibility
of pushing it even further down if fill_sha1_path() learns
to work on strbufs.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The alternate_object_database struct uses a single buffer
both for storing the path to the alternate, and as a scratch
buffer for forming object names. This is efficient (since
otherwise we'd end up storing the path twice), but it makes
life hard for callers who just want to know the path to the
alternate. They have to remember to stop reading after
"alt->name - alt->base" bytes, and to subtract one for the
trailing '/'.
It would be much simpler if they could simply access a
NUL-terminated path string. We could encapsulate this in a
function which puts a NUL in the scratch buffer and returns
the string, but that opens up questions about the lifetime
of the result. The first time another caller uses the
alternate, the scratch buffer may get other data tacked onto
it.
Let's instead just store the root path separately from the
scratch buffer. There aren't enough alternates being stored
for the duplicated data to matter for performance, and this
keeps things simple and safe for the callers.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Allocating a struct alternate_object_database is tricky, as
we must over-allocate the buffer to provide scratch space,
and then put in particular '/' and NUL markers.
Let's encapsulate this in a function so that the complexity
doesn't leak into callers (and so that we can modify it
later).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The submodule code wants to temporarily add an alternate
object store to our in-memory alt_odb list, but does it
manually. Let's provide a helper so it can reuse the code in
link_alt_odb_entry().
While we're adding our new add_to_alternates_memory(), let's
document add_to_alternates_file(), as the two are related.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add a super-prefix environment variable 'GIT_INTERNAL_SUPER_PREFIX'
which can be used to specify a path from above a repository down to its
root. When such a super-prefix is specified, the paths reported by Git
are prefixed with it to make them relative to that directory "above".
The paths given by the user on the command line
(e.g. "git subcmd --output-file=path/to/a/file" and pathspecs) are taken
relative to the directory "above" to match.
The immediate use of this option is by commands which have a
--recurse-submodule option in order to give context to submodules about
how they were invoked. This option is currently only allowed for
builtins which support a super-prefix.
Signed-off-by: Brandon Williams <bmwill@google.com>
Reviewed-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When given an abbreviated object name that is not (or more
realistically, "no longer") unique, we gave a fatal error
"ambiguous argument". This error is now accompanied by hints that
lists the objects that begins with the given prefix. During the
course of development of this new feature, numerous minor bugs were
uncovered and corrected, the most notable one of which is that we
gave "short SHA1 xxxx is ambiguous." twice without good reason.
* jk/ambiguous-short-object-names:
get_short_sha1: make default disambiguation configurable
get_short_sha1: list ambiguous objects on error
for_each_abbrev: drop duplicate objects
sha1_array: let callbacks interrupt iteration
get_short_sha1: mark ambiguity error for translation
get_short_sha1: NUL-terminate hex prefix
get_short_sha1: refactor init of disambiguation code
get_short_sha1: parse tags when looking for treeish
get_sha1: propagate flags to child functions
get_sha1: avoid repeating ourselves via ONLY_TO_DIE
get_sha1: detect buggy calls with multiple disambiguators
The get_short_sha1() is only about reading short sha1s; we
do call it in a loop to check "is this long enough" for each
object, but otherwise it should not need to know about
things like our default_abbrev setting.
So instead of asking it to set default_automatic_abbrev as a
side-effect, let's just have find_unique_abbrev() pick the
right place to start its loop. This requires a separate
approximate_object_count() function, but that naturally
belongs with the rest of sha1_file.c.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"git init" tried to record core.worktree in the repository's
'config' file when GIT_WORK_TREE environment variable was set and
it was different from where GIT_DIR appears as ".git" at its top,
but the logic was faulty when .git is a "gitdir:" file that points
at the real place, causing trouble in working trees that are
managed by "git worktree". This has been corrected.
* nd/init-core-worktree-in-multi-worktree-world:
init: kill git_link variable
init: do not set unnecessary core.worktree
init: kill set_git_dir_init()
init: call set_git_dir_init() from within init_db()
init: correct re-initialization from a linked worktree
In fairly early days we somehow decided to abbreviate object names
down to 7-hexdigits, but as projects grow, it is becoming more and
more likely to see such a short object names made in earlier days
and recorded in the log messages no longer unique.
Currently the Linux kernel project needs 11 to 12 hexdigits, while
Git itself needs 10 hexdigits to uniquely identify the objects they
have, while many smaller projects may still be fine with the
original 7-hexdigit default. One-size does not fit all projects.
Introduce a mechanism, where we estimate the number of objects in
the repository upon the first request to abbreviate an object name
with the default setting and come up with a sane default for the
repository. Based on the expectation that we would see collision in
a repository with 2^(2N) objects when using object names shortened
to first N bits, use sufficient number of hexdigits to cover the
number of objects in the repository. Each hexdigit (4-bits) we add
to the shortened name allows us to have four times (2-bits) as many
objects in the repository.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We'll be introducing a new way to decide the default abbreviation
length by initialising DEFAULT_ABBREV to -1 to signal the first call
to "find unique abbreviation" codepath to compute a reasonable value
based on the number of objects we have to avoid collisions.
We have long relied on DEFAULT_ABBREV being a positive concrete
value that is used as the abbreviation length when no extra
configuration or command line option has overridden it. Some
codepaths wants to use such a positive concrete default value
even before making their first request to actually trigger the
computation for the auto sized default.
Introduce FALLBACK_DEFAULT_ABBREV and use it to the code that
attempts to align the report from "git fetch". For now, this
macro is also used to initialize the default_abbrev variable,
but the auto-sizing code will use -1 and then use the value of
FALLBACK_DEFAULT_ABBREV as the starting point of auto-sizing.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"git add --chmod=+x <pathspec>" added recently only toggled the
executable bit for paths that are either new or modified. This has
been corrected to flip the executable bit for all paths that match
the given pathspec.
* tg/add-chmod+x-fix:
t3700-add: do not check working tree file mode without POSIXPERM
t3700-add: create subdirectory gently
add: modify already added files when --chmod is given
read-cache: introduce chmod_index_entry
update-index: add test for chmod flags
When we find ambiguous short sha1s, we may get a
disambiguation rule from our caller's context. But if we
don't, we fall back to treating all sha1s the same, even
though most projects will tend to refer only to commits by
their short sha1s.
This patch introduces a configuration option that lets the
user pick a different fallback (e.g., only commits). It's
possible that we may want to make this the default, but it's
a good idea to start as a config option for two reasons:
1. It lets people experiment with this and see if it's a
good idea (i.e., the "tend to" above is an assumption;
we don't really know if this will break some obscure
cases).
2. Even if we do flip the default, it gives people an
escape hatch if it causes problems (you can sometimes
override it by asking for "1234^{tree}", but not all
combinations are possible).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"git add --chmod=+x <pathspec>" added recently only toggled the
executable bit for paths that are either new or modified. This has
been corrected to flip the executable bit for all paths that match
the given pathspec.
* tg/add-chmod+x-fix:
t3700-add: do not check working tree file mode without POSIXPERM
t3700-add: create subdirectory gently
add: modify already added files when --chmod is given
read-cache: introduce chmod_index_entry
update-index: add test for chmod flags
The get_sha1() family of functions takes a flags field, but
some of the flags are mutually exclusive. In particular, we
can only handle one disambiguating function, and the flags
quietly override each other. Let's instead detect these as
programming bugs.
Technically some of the flags are supersets of the others,
so treating COMMITTISH|TREEISH as just COMMITTISH is not
wrong, but it's a good sign the caller is confused. And
certainly asking for BLOB|TREE does not work.
We can do the check easily with some bit-twiddling, and as a
bonus, the bit-mask of disambiguators will come in handy in
a future patch.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The next commit requires that set_git_dir_init() must be called before
init_db(). Let's make sure nobody can do otherwise.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add a static initializer for struct checkout and use it throughout the
code base. It's shorter, avoids a memset(3) call and makes sure the
base_dir member is initialized to a valid (empty) string.
Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
There were numerous corner cases in which the configuration files
are read and used or not read at all depending on the directory a
Git command was run, leading to inconsistent behaviour. The code
to set-up repository access at the beginning of a Git process has
been updated to fix them.
* jk/setup-sequence-update:
t1007: factor out repeated setup
init: reset cached config when entering new repo
init: expand comments explaining config trickery
config: only read .git/config from configured repos
test-config: setup git directory
t1302: use "git -C"
pager: handle early config
pager: use callbacks instead of configset
pager: make pager_program a file-local static
pager: stop loading git_default_config()
pager: remove obsolete comment
diff: always try to set up the repository
diff: handle --no-index prefixes consistently
diff: skip implicit no-index check when given --no-index
patch-id: use RUN_SETUP_GENTLY
hash-object: always try to set up the git repository
The "unsigned char sha1[20]" to "struct object_id" conversion
continues. Notable changes in this round includes that ce->sha1,
i.e. the object name recorded in the cache_entry, turns into an
object_id.
It had merge conflicts with a few topics in flight (Christian's
"apply.c split", Dscho's "cat-file --filters" and Jeff Hostetler's
"status --porcelain-v2"). Extra sets of eyes double-checking for
mismerges are highly appreciated.
* bc/object-id:
builtin/reset: convert to use struct object_id
builtin/commit-tree: convert to struct object_id
builtin/am: convert to struct object_id
refs: add an update_ref_oid function.
sha1_name: convert get_sha1_mb to struct object_id
builtin/update-index: convert file to struct object_id
notes: convert init_notes to use struct object_id
builtin/rm: convert to use struct object_id
builtin/blame: convert file to use struct object_id
Convert read_mmblob to take struct object_id.
notes-merge: convert struct notes_merge_pair to struct object_id
builtin/checkout: convert some static functions to struct object_id
streaming: make stream_blob_to_fd take struct object_id
builtin: convert textconv_object to use struct object_id
builtin/cat-file: convert some static functions to struct object_id
builtin/cat-file: convert struct expand_data to use struct object_id
builtin/log: convert some static functions to use struct object_id
builtin/blame: convert struct origin to use struct object_id
builtin/apply: convert static functions to struct object_id
cache: convert struct cache_entry to use struct object_id
When the chmod option was added to git add, it was hooked up to the diff
machinery, meaning that it only works when the version in the index
differs from the version on disk.
As the option was supposed to mirror the chmod option in update-index,
which always changes the mode in the index, regardless of the status of
the file, make sure the option behaves the same way in git add.
Signed-off-by: Thomas Gummerer <t.gummerer@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
As there are chmod options for both add and update-index, introduce a
new chmod_index_entry function to do the work. Use it in update-index,
while it will be used in add in the next patch.
Signed-off-by: Thomas Gummerer <t.gummerer@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
After we copy the templates into place, we re-read the
config in case we copied in a default config file. But since
git_config() is backed by a cache these days, it's possible
that the call will not actually touch the filesystem at all;
we need to tell it that something has changed behind the
scenes.
Note that we also need to reset the shared_repository
config. At first glance, it seems like this should probably
just be folded into git_config_clear(). But unfortunately
that is not quite right. The shared repository value may
come from config, _or_ it may have been set manually. So
only the caller who knows whether or not they set it is the
one who can clear it (and indeed, if you _do_ put it into
git_config_clear(), then many tests fail, as we have to
clear the config cache any time we set a new config
variable).
There are three tests here. The first two actually pass
already, though it's largely luck: they just don't happen to
actually read any config before we enter the new repo.
But the third one does fail without this patch; we look at
core.sharedrepository while creating the directory, but need
to make sure the value from the template config overrides
it.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When git_config() runs, it looks in the system, user-wide,
and repo-level config files. It gets the latter by calling
git_pathdup(), which in turn calls get_git_dir(). If we
haven't set up the git repository yet, this may simply
return ".git", and we will look at ".git/config". This
seems like it would be helpful (presumably we haven't set up
the repository yet, so it tries to find it), but it turns
out to be a bad idea for a few reasons:
- it's not sufficient, and therefore hides bugs in a
confusing way. Config will be respected if commands are
run from the top-level of the working tree, but not from
a subdirectory.
- it's not always true that we haven't set up the
repository _yet_; we may not want to do it at all. For
instance, if you run "git init /some/path" from inside
another repository, it should not load config from the
existing repository.
- there might be a path ".git/config", but it is not the
actual repository we would find via setup_git_directory().
This may happen, e.g., if you are storing a git
repository inside another git repository, but have
munged one of the files in such a way that the
inner repository is not valid (e.g., by removing HEAD).
We have at least two bugs of the second type in git-init,
introduced by ae5f677 (lazily load core.sharedrepository,
2016-03-11). It causes init to use git_configset(), which
loads all of the config, including values from the current
repo (if any). This shows up in two ways:
1. If we happen to be in an existing repository directory,
we'll read and respect core.sharedrepository from it,
even though it should have no bearing on the new
repository. A new test in t1301 covers this.
2. Similarly, if we're in an existing repo that sets
core.logallrefupdates, that will cause init to fail to
set it in a newly created repository (because it thinks
that the user's templates already did so). A new test
in t0001 covers this.
We also need to adjust an existing test in t1302, which
gives another example of why this patch is an improvement.
That test creates an embedded repository with a bogus
core.repositoryformatversion of "99". It wants to make sure
that we actually stop at the bogus repo rather than
continuing upward to find the outer repo. So it checks that
"git config core.repositoryformatversion" returns 99. But
that only works because we blindly read ".git/config", even
though we _know_ we're in a repository whose vintage we do
not understand.
After this patch, we avoid reading config from the unknown
vintage repository at all, which is a safer choice. But we
need to tweak the test, since core.repositoryformatversion
will not return 99; it will claim that it could not find the
variable at all.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
