Commit 3a2e0824 ("object-store: provide helpers for loose_objects_cache",
2018-11-12) moved the cache-loading code from find_short_object_filename(),
but forgot the line that releases the path strbuf.
Reported-by: René Scharfe <l.s.r@web.de> Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Commit 024aa4696c (fetch-pack.c: use oidset to check existence of loose
object, 2018-03-14) added a cache to avoid calling stat() for a bunch of
loose objects we don't have.
Now that OBJECT_INFO_QUICK handles this caching itself, we can drop the
custom solution.
Note that this might perform slightly differently, as the original code
stopped calling readdir() when we saw more loose objects than there were
refs. So:
1. The old code might have spent work on readdir() to fill the cache,
but then decided there were too many loose objects, wasting that
effort.
2. The new code might spend a lot of time on readdir() if you have a
lot of loose objects, even though there are very few objects to
ask about.
In practice it probably won't matter either way; see the previous commit
for some discussion of the tradeoff.
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
sha1-file: use loose object cache for quick existence check
In cases where we expect to ask has_sha1_file() about a lot of objects
that we are not likely to have (e.g., during fetch negotiation), we
already use OBJECT_INFO_QUICK to sacrifice accuracy (due to racing with
a simultaneous write or repack) for speed (we avoid re-scanning the pack
directory).
However, even checking for loose objects can be expensive, as we will
stat() each one. On many systems this cost isn't too noticeable, but
stat() can be particularly slow on some operating systems, or due to
network filesystems.
Since the QUICK flag already tells us that we're OK with a slightly
stale answer, we can use that as a cue to look in our in-memory cache of
each object directory. That basically trades an in-memory binary search
for a stat() call.
Note that it is possible for this to actually be _slower_. We'll do a
full readdir() to fill the cache, so if you have a very large number of
loose objects and a very small number of lookups, that readdir() may end
up more expensive.
This shouldn't be a big deal in practice. If you have a large number of
reachable loose objects, you'll already run into performance problems
(which you should remedy by repacking). You may have unreachable objects
which wouldn't otherwise impact performance. Usually these would go away
with the prune step of "git gc", but they may be held for up to 2 weeks
in the default configuration.
So it comes down to how many such objects you might reasonably expect to
have, how much slower is readdir() on N entries versus M stat() calls
(and here we really care about the syscall backing readdir(), like
getdents() on Linux, but I'll just call this readdir() below).
If N is much smaller than M (a typical packed repo), we know this is a
big win (few readdirs() followed by many uses of the resulting cache).
When N and M are similar in size, it's also a win. We care about the
latency of making a syscall, and readdir() should be giving us many
values in a single call. How many?
On Linux, running "strace -e getdents ls" shows a 32k buffer getting 512
entries per call (which is 64 bytes per entry; the name itself is 38
bytes, plus there are some other fields). So we can imagine that this is
always a win as long as the number of loose objects in the repository is
a factor of 500 less than the number of lookups you make. It's hard to
auto-tune this because we don't generally know up front how many lookups
we're going to do. But it's unlikely for this to perform significantly
worse.
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
object-store: provide helpers for loose_objects_cache
Our object_directory struct has a loose objects cache that all users of
the struct can see. But the only one that knows how to load the cache is
find_short_object_filename(). Let's extract that logic in to a reusable
function.
While we're at it, let's also reset the cache when we re-read the object
directories. This shouldn't have an impact on performance, as re-reads
are meant to be rare (and are already expensive, so we avoid them with
things like OBJECT_INFO_QUICK).
Since the cache is already meant to be an approximation, it's tempting
to skip even this bit of safety. But it's necessary to allow more code
to use it. For instance, fetch-pack explicitly re-reads the object
directory after performing its fetch, and would be confused if we didn't
clear the cache.
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
sha1-file: use an object_directory for the main object dir
Our handling of alternate object directories is needlessly different
from the main object directory. As a result, many places in the code
basically look like this:
do_something(r->objects->objdir);
for (odb = r->objects->alt_odb_list; odb; odb = odb->next)
do_something(odb->path);
That gets annoying when do_something() is non-trivial, and we've
resorted to gross hacks like creating fake alternates (see
find_short_object_filename()).
Instead, let's give each raw_object_store a unified list of
object_directory structs. The first will be the main store, and
everything after is an alternate. Very few callers even care about the
distinction, and can just loop over the whole list (and those who care
can just treat the first element differently).
A few observations:
- we don't need r->objects->objectdir anymore, and can just
mechanically convert that to r->objects->odb->path
- object_directory's path field needs to become a real pointer rather
than a FLEX_ARRAY, in order to fill it with expand_base_dir()
- we'll call prepare_alt_odb() earlier in many functions (i.e.,
outside of the loop). This may result in us calling it even when our
function would be satisfied looking only at the main odb.
But this doesn't matter in practice. It's not a very expensive
operation in the first place, and in the majority of cases it will
be a noop. We call it already (and cache its results) in
prepare_packed_git(), and we'll generally check packs before loose
objects. So essentially every program is going to call it
immediately once per program.
Arguably we should just prepare_alt_odb() immediately upon setting
up the repository's object directory, which would save us sprinkling
calls throughout the code base (and forgetting to do so has been a
source of subtle bugs in the past). But I've stopped short of that
here, since there are already a lot of other moving parts in this
patch.
- Most call sites just get shorter. The check_and_freshen() functions
are an exception, because they have entry points to handle local and
nonlocal directories separately.
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
handle alternates paths the same as the main object dir
When we generate loose file paths for the main object directory, the
caller provides a buffer to loose_object_path (formerly sha1_file_name).
The callers generally keep their own static buffer to avoid excessive
reallocations.
But for alternate directories, each struct carries its own scratch
buffer. This is needlessly different; let's unify them.
We could go either direction here, but this patch moves the alternates
struct over to the main directory style (rather than vice-versa).
Technically the alternates style is more efficient, as it avoids
rewriting the object directory name on each call. But this is unlikely
to matter in practice, as we avoid reallocations either way (and nobody
has ever noticed or complained that the main object directory is copying
a few extra bytes before making a much more expensive system call).
And this has the advantage that the reusable buffers are tied to
particular calls, which makes the invalidation rules simpler (for
example, the return value from stat_sha1_file() used to be invalidated
by basically any other object call, but now it is affected only by other
calls to stat_sha1_file()).
We do steal the trick from alt_sha1_path() of returning a pointer to the
filled buffer, which makes a few conversions more convenient.
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
sha1_file_name(): overwrite buffer instead of appending
The sha1_file_name() function is used to generate the path to a loose
object in the object directory. It doesn't make much sense for it to
append, since the the path we write may be absolute (i.e., you cannot
reliably build up a path with it). Because many callers use it with a
static buffer, they have to strbuf_reset() manually before each call
(and the other callers always use an empty buffer, so they don't care
either way). Let's handle this automatically.
Since we're changing the semantics, let's take the opportunity to give
it a more hash-neutral name (which will also catch any callers from
topics in flight).
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
rename "alternate_object_database" to "object_directory"
In preparation for unifying the handling of alt odb's and the normal
repo object directory, let's use a more neutral name. This patch is
purely mechanical, swapping the type name, and converting any variables
named "alt" to "odb". There should be no functional change, but it will
reduce the noise in subsequent diffs.
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
submodule--helper: prefer strip_suffix() to ends_with()
Using strip_suffix() lets us avoid repeating ourselves. It also makes
the handling of "/" a bit less subtle (we strip one less character than
we matched in order to leave it in place, but we can just as easily
include the "/" when we add more path components).
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
The run-command API makes no promises about what is left in a struct
child_process after a command finishes, and it's not safe to simply
reuse it again for a similar command. In particular:
- if you use child->args or child->env_array, they are cleared after
finish_command()
- likewise, start_command() may point child->argv at child->args->argv;
reusing that would lead to accessing freed memory
- the in/out/err may hold pipe descriptors from the previous run
These two calls are _probably_ OK because they do not use any of those
features. But it's only by chance, and may break in the future; let's
reinitialize our struct for each program we run.
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Windows port learned to use nano-second resolution file timestamps.
* js/mingw-ns-filetime:
mingw: implement nanosecond-precision file times
mingw: replace MSVCRT's fstat() with a Win32-based implementation
mingw: factor out code to set stat() data
Operations on promisor objects make sense in the context of only a
small subset of the commands that internally use the revisions
machinery, but the "--exclude-promisor-objects" option were taken
and led to nonsense results by commands like "log", to which it
didn't make much sense. This has been corrected.
* md/exclude-promisor-objects-fix:
exclude-promisor-objects: declare when option is allowed
Documentation/git-log.txt: do not show --exclude-promisor-objects
"git send-email" learned to disable SMTP authentication via the
"--smtp-auth=none" option, even when the smtp username is given
(which turns the authentication on by default).
The command line completion machinery (in contrib/) has been
updated to allow the completion script to tweak the list of options
that are reported by the parse-options machinery correctly.
* nd/completion-negation:
completion: fix __gitcomp_builtin no longer consider extra options
"git fetch" over protocol v2 into a shallow repository failed to
fetch full history behind a new tip of history that was diverged
before the cut-off point of the history that was previously fetched
shallowly.
* jt/upload-pack-v2-fix-shallow:
upload-pack: clear flags before each v2 request
upload-pack: make want_obj not global
upload-pack: make have_obj not global
Some codepaths failed to form a proper URL when .gitmodules record
the URL to a submodule repository as relative to the repository of
superproject, which has been corrected.
* sb/submodule-url-to-absolute:
submodule helper: convert relative URL to absolute URL if needed
"git repack" in a shallow clone did not correctly update the
shallow points in the repository, leading to a repository that
does not pass fsck.
* js/shallow-and-fetch-prune:
repack -ad: prune the list of shallow commits
shallow: offer to prune only non-existing entries
repack: point out a bug handling stale shallow info
On platforms with recent cURL library, http.sslBackend configuration
variable can be used to choose a different SSL backend at runtime.
The Windows port uses this mechanism to switch between OpenSSL and
Secure Channel while talking over the HTTPS protocol.
* js/mingw-http-ssl:
http: when using Secure Channel, ignore sslCAInfo by default
http: add support for disabling SSL revocation checks in cURL
http: add support for selecting SSL backends at runtime
New "--pretty=format:" placeholders %GF and %GP that show the GPG
key fingerprints have been invented.
* mg/gpg-fingerprint:
gpg-interface.c: obtain primary key fingerprint as well
gpg-interface.c: support getting key fingerprint via %GF format
gpg-interface.c: use flags to determine key/signer info presence
* en/merge-cleanup-more:
merge-recursive: avoid showing conflicts with merge branch before HEAD
merge-recursive: improve auto-merging messages with path collisions
"git rebase -i" learned a new insn, 'break', that the user can
insert in the to-do list. Upon hitting it, the command returns
control back to the user.
* js/rebase-i-break:
rebase -i: introduce the 'break' command
rebase -i: clarify what happens on a failed `exec`
"git rebase" that has recently been rewritten in C had a few issues
in its "--autstash" feature, which have been corrected.
* js/rebase-autostash-fix:
rebase --autostash: fix issue with dirty submodules
rebase --autostash: demonstrate a problem with dirty submodules
rebase (autostash): use an explicit OID to apply the stash
rebase (autostash): store the full OID in <state-dir>/autostash
rebase (autostash): avoid duplicate call to state_dir_path()
"rebase" that has been rewritten learns the new calling convention
used by "rebase -i" that was rewritten in C, tying the loose end
between two GSoC topics that stomped on each other's toes.
* js/rebase-in-c-5.5-work-with-rebase-i-in-c:
builtin rebase: prepare for builtin rebase -i
* pk/rebase-in-c-5-test:
builtin rebase: error out on incompatible option/mode combinations
builtin rebase: use no-op editor when interactive is "implied"
builtin rebase: show progress when connected to a terminal
builtin rebase: fast-forward to onto if it is a proper descendant
builtin rebase: optionally pass custom reflogs to reset_head()
builtin rebase: optionally auto-detect the upstream
* pk/rebase-in-c-4-opts:
builtin rebase: support --root
builtin rebase: add support for custom merge strategies
builtin rebase: support `fork-point` option
merge-base --fork-point: extract libified function
builtin rebase: support --rebase-merges[=[no-]rebase-cousins]
builtin rebase: support `--allow-empty-message` option
builtin rebase: support `--exec`
builtin rebase: support `--autostash` option
builtin rebase: support `-C` and `--whitespace=<type>`
builtin rebase: support `--gpg-sign` option
builtin rebase: support `--autosquash`
builtin rebase: support `keep-empty` option
builtin rebase: support `ignore-date` option
builtin rebase: support `ignore-whitespace` option
builtin rebase: support --committer-date-is-author-date
builtin rebase: support --rerere-autoupdate
builtin rebase: support --signoff
builtin rebase: allow selecting the rebase "backend"
* pk/rebase-in-c-3-acts:
builtin rebase: stop if `git am` is in progress
builtin rebase: actions require a rebase in progress
builtin rebase: support --edit-todo and --show-current-patch
builtin rebase: support --quit
builtin rebase: support --abort
builtin rebase: support --skip
builtin rebase: support --continue
* pk/rebase-in-c-2-basic:
builtin rebase: support `git rebase <upstream> <switch-to>`
builtin rebase: only store fully-qualified refs in `options.head_name`
builtin rebase: start a new rebase only if none is in progress
builtin rebase: support --force-rebase
builtin rebase: try to fast forward when possible
builtin rebase: require a clean worktree
builtin rebase: support the `verbose` and `diffstat` options
builtin rebase: support --quiet
builtin rebase: handle the pre-rebase hook and --no-verify
builtin rebase: support `git rebase --onto A...B`
builtin rebase: support --onto
Rewrite of the remaining "rebase -i" machinery in C.
* ag/rebase-i-in-c:
rebase -i: move rebase--helper modes to rebase--interactive
rebase -i: remove git-rebase--interactive.sh
rebase--interactive2: rewrite the submodes of interactive rebase in C
rebase -i: implement the main part of interactive rebase as a builtin
rebase -i: rewrite init_basic_state() in C
rebase -i: rewrite write_basic_state() in C
rebase -i: rewrite the rest of init_revisions_and_shortrevisions() in C
rebase -i: implement the logic to initialize $revisions in C
rebase -i: remove unused modes and functions
rebase -i: rewrite complete_action() in C
t3404: todo list with commented-out commands only aborts
sequencer: change the way skip_unnecessary_picks() returns its result
sequencer: refactor append_todo_help() to write its message to a buffer
rebase -i: rewrite checkout_onto() in C
rebase -i: rewrite setup_reflog_action() in C
sequencer: add a new function to silence a command, except if it fails
rebase -i: rewrite the edit-todo functionality in C
editor: add a function to launch the sequence editor
rebase -i: rewrite append_todo_help() in C
sequencer: make three functions and an enum from sequencer.c public
* pk/rebase-in-c:
builtin/rebase: support running "git rebase <upstream>"
rebase: refactor common shell functions into their own file
rebase: start implementing it as a builtin
Reorganize some tests and rename them; "ls t/" now gives a better
overview of what is tested for these scripts than before.
* ss/rename-tests:
t7501: rename commit test to comply with naming convention
t7500: rename commit tests script to comply with naming convention
t7502: rename commit test script to comply with naming convention
t7509: cleanup description and filename
t2000: rename and combine checkout clash tests
The receive.denyCurrentBranch=updateInstead codepath kicked in even
when the push should have been rejected due to other reasons, such
as it does not fast-forward or the update-hook rejects it, which
has been corrected.
* jc/receive-deny-current-branch-fix:
receive: denyCurrentBranch=updateinstead should not blindly update
Under certain circumstances, "git diff D:/a/b/c D:/a/b/d" on
Windows would strip initial parts from the paths because they
were not recognized as absolute, which has been corrected.
* js/diff-notice-has-drive-prefix:
diff: don't attempt to strip prefix from absolute Windows paths
More codepaths are moving away from hardcoded hash sizes.
* bc/hash-transition-part-15:
rerere: convert to use the_hash_algo
submodule: make zero-oid comparison hash function agnostic
apply: rename new_sha1_prefix and old_sha1_prefix
apply: replace hard-coded constants
tag: express constant in terms of the_hash_algo
transport: use parse_oid_hex instead of a constant
upload-pack: express constants in terms of the_hash_algo
refs/packed-backend: express constants using the_hash_algo
packfile: express constants in terms of the_hash_algo
pack-revindex: express constants in terms of the_hash_algo
builtin/fetch-pack: remove constants with parse_oid_hex
builtin/mktree: remove hard-coded constant
builtin/repack: replace hard-coded constants
pack-bitmap-write: use GIT_MAX_RAWSZ for allocation
object_id.cocci: match only expressions of type 'struct object_id'
"git send-email" learned to grab address-looking string on any
trailer whose name ends with "-by"; --suppress-cc=misc-by on the
command line, or setting sendemail.suppresscc configuration
variable to "misc-by", can be used to disable this behaviour.
This is a backward-incompatible change that may surprise existing
users.
* rv/send-email-cc-misc-by:
send-email: also pick up cc addresses from -by trailers
send-email: only consider lines containing @ or <> for automatic Cc'ing
Documentation/git-send-email.txt: style fixes
The "rev-list --filter" feature learned to exclude all trees via
"tree:0" filter.
* md/filter-trees:
list-objects: support for skipping tree traversal
filter-trees: code clean-up of tests
list-objects-filter: implement filter tree:0
list-objects-filter-options: do not over-strbuf_init
list-objects-filter: use BUG rather than die
revision: mark non-user-given objects instead
rev-list: handle missing tree objects properly
list-objects: always parse trees gently
list-objects: refactor to process_tree_contents
list-objects: store common func args in struct
Add the necessary #includes and forward declarations to allow the header
file to pass the 'hdr-check' target.
Note that, since this header includes the commit-slab implementation
header file (indirectly via commit-slab.h), some of the commit-slab
inline functions (e.g contains_cache_at_peek()) will not compile without
the complete type of 'struct commit'. Hence, we replace the forward
declaration of 'struct commit' with the an #include of the 'commit.h'
header file.
It is possible, using the 'commit-slab-{decl,impl}.h' files, to avoid
this inclusion of the 'commit.h' header. Commit a9f1f1f9f8 ("commit-slab.h:
code split", 2018-05-19) separated the commit-slab interface from its
implementation, to allow for the definition of a public commit-slab data
structure. This enabled us to avoid including the commit-slab implementation
in a header file, which could result in the replication of the commit-slab
functions in each compilation unit in which it was included.
Indeed, if you compile with optimizations disabled, then run this script:
you will find 24 copies of the commit-slab routines for the contains_cache.
Of course, when you enable optimizations again, these duplicate static
functions (mostly) disappear. Compiling with gcc at -O2, leaves two static
functions, thus:
$ nm commit-reach.o | grep contains_cache 0000000000000870 t contains_cache_at_peek.isra.1.constprop.6
$ nm ref-filter.o | grep contains_cache 00000000000002b0 t clear_contains_cache.isra.14
$
However, using a shared 'contains_cache' would result in all six of the
above functions as external public functions in the git binary. At present,
only three of these functions are actually called, so the trade-off
seems to favour letting the compiler inline the commit-slab functions.
Signed-off-by: Ramsay Jones <ramsay@ramsayjones.plus.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
ewok_rlw.h: add missing 'inline' to function definition
The 'ewok_rlw.h' header file contains the rlw_get_run_bit() function
definition, which is marked as 'static' but not 'inline'. At least when
compiled by gcc, with the default -O2 optimization level, the function
is actually inlined and leaves no static version in the ewah_bitmap.o
and ewah_rlw.o object files. Despite this, add the missing 'inline'
keyword to better describe the intended behaviour.
Signed-off-by: Ramsay Jones <ramsay@ramsayjones.plus.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
t3404-rebase-interactive: test abbreviated commands
Make sure that each short command is tested at least once. To
not exacerbate the runtime of the test script, do not add new
tests, but modify existing ones according to these criteria:
- The test does not have a prerequisite.
- The 'git rebase' command is not guarded by test_must_fail.
The pick commands are optional in the FAKE_LINES variable, but
when used, they do end up in the insn sheet. Test them, too.
Signed-off-by: Johannes Sixt <j6t@kdbg.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
sequencer: cleanup for gcc warning in non developer mode
as shown by:
sequencer.c: In function ‘write_basic_state’:
sequencer.c:2392:37: warning: zero-length gnu_printf format string [-Wformat-zero-length]
write_file(rebase_path_verbose(), "");
where write_file will create an empty file if told to write an empty string
as can be inferred by the previous call
the somehow more convoluted syntax works around the issue by providing a non
empty format string and is already being used for the abort safety file since 1e41229d96 ("sequencer: make sequencer abort safer", 2016-12-07)
Signed-off-by: Carlo Marcelo Arenas Belón <carenas@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
The logic to select the default user name and e-mail on Windows has
been improved.
* js/mingw-default-ident:
mingw: use domain information for default email
getpwuid(mingw): provide a better default for the user name
getpwuid(mingw): initialize the structure only once
* ld/p4-unshelve:
git-p4: fully support unshelving changelists
git-p4: unshelve into refs/remotes/p4-unshelved, not refs/remotes/p4/unshelved
git-p4: do not fail in verbose mode for missing 'fileSize' key
The documentation of "git gc" has been updated to mention that it
is no longer limited to "pruning away crufts" but also updates
ancillary files like commit-graph as a part of repository
optimization.
* ab/gc-doc-update:
gc doc: mention the commit-graph in the intro
"git cmd --help" when "cmd" is aliased used to only say "cmd is
aliased to ...". Now it shows that to the standard error stream
and runs "git $cmd --help" where $cmd is the first word of the
alias expansion.
This could be misleading for those who alias a command with options
(e.g. with "[alias] cpn = cherry-pick -n", "git cpn --help" would
show the manual of "cherry-pick", and the reader would not be told
to pay close attention to the part that describes the "--no-commit"
option until closing the pager that showed the contents of the
manual, if the pager is configured to restore the original screen,
or would not be told at all, if the pager simply makes the message
on the standard error scroll away.
* rv/alias-help:
git-help.txt: document "git help cmd" vs "git cmd --help" for aliases
git.c: handle_alias: prepend alias info when first argument is -h
help: redirect to aliased commands for "git cmd --help"
"git log --graph" showing an octopus merge sometimes miscounted the
number of display columns it is consuming to show the merge and its
parent commits, which has been corrected.
* np/log-graph-octopus-fix:
log: fix coloring of certain octopus merge shapes
The codepath to support the experimental split-index mode had
remaining "racily clean" issues fixed.
* sg/split-index-racefix:
split-index: BUG() when cache entry refers to non-existing shared entry
split-index: smudge and add racily clean cache entries to split index
split-index: don't compare cached data of entries already marked for split index
split-index: count the number of deleted entries
t1700-split-index: date back files to avoid racy situations
split-index: add tests to demonstrate the racy split index problem
t1700-split-index: document why FSMONITOR is disabled in this test script
The result of coverage test can be combined with "git blame" to
check the test coverage of code introduced recently with a new
'coverage-diff' tool (in contrib/).