This commit provides basic utility classes for the reftable library.
Signed-off-by: Han-Wen Nienhuys <hanwen@google.com>
Helped-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
trace2 logs learned to show parent process name to see in what
context Git was invoked.
* es/trace2-log-parent-process-name:
tr2: log parent process name
tr2: make process info collection platform-generic
Pathname expansion (like "~username/") learned a way to specify a
location relative to Git installation (e.g. its $sharedir which is
$(prefix)/share), with "%(prefix)".
* js/expand-runtime-prefix:
expand_user_path: allow in-flight topics to keep using the old name
interpolate_path(): allow specifying paths relative to the runtime prefix
Use a better name for the function interpolating paths
expand_user_path(): clarify the role of the `real_home` parameter
expand_user_path(): remove stale part of the comment
tests: exercise the RUNTIME_PREFIX feature
With a54e938e5b (strbuf: support long paths w/o read rights in
strbuf_getcwd() on FreeBSD, 2017-03-26) we had t0001 break on systems
like OpenBSD and AIX whose getcwd(3) has standard (but not like glibc
et al) behavior.
This was partially fixed in bed67874e2 (t0001: skip test with
restrictive permissions if getpwd(3) respects them, 2017-08-07).
The problem with that fix is that while its analysis of the problem is
correct, it doesn't actually call getcwd(3), instead it invokes "pwd
-P". There is no guarantee that "pwd -P" is going to call getcwd(3),
as opposed to e.g. being a shell built-in.
On AIX under both bash and ksh this test breaks because "pwd -P" will
happily display the current working directory, but getcwd(3) called by
the "git init" we're testing here will fail to get it.
I checked whether clobbering the $PWD environment variable would
affect it, and it didn't. Presumably these shells keep track of their
working directory internally.
There's possible follow-up work here in teaching strbuf_getcwd() to
get the working directory with whatever method "pwd" uses on these
platforms. See [1] for a discussion of that, but let's take the easy
way out here and just skip these tests by fixing the
GETCWD_IGNORES_PERMS prerequisite to match the limitations of
strbuf_getcwd().
1. https://lore.kernel.org/git/b650bef5-d739-d98d-e9f1-fa292b6ce982@web.de/
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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
Originally, we refrained from adding a regression test in 7b6c6496374
(system_path(): Add prefix computation at runtime if RUNTIME_PREFIX set,
2008-08-10), and in 226c0ddd0d (exec_cmd: RUNTIME_PREFIX on some POSIX
systems, 2018-04-10).
The reason was that it was deemed too tricky to test.
Turns out that it is not tricky to test at all: we simply create a
pseudo-root, copy the `git` executable into the `git/` subdirectory of
that pseudo-root, then copy a script into the `libexec/git-core/`
directory and expect that to be picked up.
As long as the trash directory is in a location where binaries can be
executed, this works.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
To pave the way for non-Windows platforms to define
trace2_collect_process_info(), reorganize the stub-or-definition schema
to something which doesn't directly reference Windows.
Platforms which want to collect parent process information in the
future should:
1. Add an implementation to compat/ (e.g. compat/somearch/procinfo.c)
2. Add that object to COMPAT_OBJS to config.mak.uname
(e.g. COMPAT_OBJS += compat/somearch/procinfo.o)
3. Define HAVE_PLATFORM_PROCINFO in config.mak.uname
In the Windows case, this definition lives in
compat/win32/trace2_win32_process_info.c, which is already conditionally
added to COMPAT_OBJS; so let's add HAVE_PLATFORM_PROCINFO to hint to the
build that compat/stub/procinfo.c should not be used.
Signed-off-by: Emily Shaffer <emilyshaffer@google.com>
Helped-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
GitHub Actions / CI update.
* js/ci-windows-update:
ci: accelerate the checkout
ci (vs-build): build with NO_GETTEXT
artifacts-tar: respect NO_GETTEXT
ci (windows): transfer also the Git-tracked files to the test jobs
ci: upgrade to using actions/{up,down}load-artifacts v2
ci (vs-build): use `cmd` to copy the DLLs, not `powershell`
ci: use the new GitHub Action to download git-sdk-64-minimal
Prepare the internals for lazily fetching objects in submodules
from their promisor remotes.
* jt/partial-clone-submodule-1:
promisor-remote: teach lazy-fetch in any repo
run-command: refactor subprocess env preparation
submodule: refrain from filtering GIT_CONFIG_COUNT
promisor-remote: support per-repository config
repository: move global r_f_p_c to repo struct
"git-svn" tests assumed that "locale -a", which is used to pick an
available UTF-8 locale, is available everywhere. A knob has been
introduced to allow testers to specify a suitable locale to use.
* dd/svn-test-wo-locale-a:
t: use user-specified utf-8 locale for testing svn
This saves 8K per `struct object_directory', meaning it saves
around 800MB in my case involving 100K alternates (half or more
of those alternates are unlikely to hold loose objects).
This is implemented in two parts: a generic, allocation-free
`cbtree' and the `oidtree' wrapper on top of it. The latter
provides allocation using alloc_state as a memory pool to
improve locality and reduce free(3) overhead.
Unlike oid-array, the crit-bit tree does not require sorting.
Performance is bound by the key length, for oidtree that is
fixed at sizeof(struct object_id). There's no need to have
256 oidtrees to mitigate the O(n log n) overhead like we did
with oid-array.
Being a prefix trie, it is natively suited for expanding short
object IDs via prefix-limited iteration in
`find_short_object_filename'.
On my busy workstation, p4205 performance seems to be roughly
unchanged (+/-8%). Startup with 100K total alternates with no
loose objects seems around 10-20% faster on a hot cache.
(800MB in memory savings means more memory for the kernel FS
cache).
The generic cbtree implementation does impose some extra
overhead for oidtree in that it uses memcmp(3) on
"struct object_id" so it wastes cycles comparing 12 extra bytes
on SHA-1 repositories. I've not yet explored reducing this
overhead, but I expect there are many places in our code base
where we'd want to investigate this.
More information on crit-bit trees: https://cr.yp.to/critbit.html
Signed-off-by: Eric Wong <e@80x24.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We obviously do not want to bundle `.mo` files during `make
artifacts-tar NO_GETTEXT=Yep`, but that was the case.
To fix that, go a step beyond just fixing the symptom, and simply
define the lists of `.po` and `.mo` files as empty if `NO_GETTEXT` is
set.
Helped-by: Matthias Aßhauer <mha1993@live.de>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Use the GNU make ".DELETE_ON_ERROR" flag in our main Makefile, as we
already do in the Documentation/Makefile since db10fc6c09 (doc:
simplify Makefile using .DELETE_ON_ERROR, 2021-05-21).
Now if a command to make X fails X will be removed, the default
behavior of GNU make is to only do so if "make" itself is interrupted
with a signal.
E.g. if we now intentionally break one of the rules with:
- mv $@+ $@
+ mv $@+ $@ && \
+ false
We'll get output like:
$ make git
CC git.o
LINK git
make: *** [Makefile:2179: git] Error 1
make: *** Deleting file 'git'
$ file git
git: cannot open `git' (No such file or directory)
Before this change we'd leave the file in place in under this
scenario.
As in db10fc6c09 this allows us to remove patterns of removing
leftover $@ files at the start of rules, since previous failing runs
of the Makefile won't have left those littered around anymore.
I'm not as confident that we should be replacing the "mv $@+ $@"
pattern entirely, since that means that external programs or one of
our other Makefiles might race and get partial content.
I'm not changing $(REMOTE_CURL_ALIASES) since that uses a ln/ln -s/cp
dance, and would require the addition of "-f" flags if the "rm" at the
start was removed. I've also got plans to fix that ln/ln -s/cp pattern
in another series.
For $(LIB_FILE) and $(XDIFF_LIB) we can rely on the "c" (create) being
present in ARFLAGS.
I'm not changing "$(ETAGS_TARGET)", "tags" and "cscope" because
they've got a messy combination of removing "$@+" not "$@" at the
beginning, or "$@*". I'm also addressing those in another series.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This is one step towards supporting partial clone submodules.
Even after this patch, we will still lack partial clone submodules
support, primarily because a lot of Git code that accesses submodule
objects does so by adding their object stores as alternates, meaning
that any lazy fetches that would occur in the submodule would be done
based on the config of the superproject, not of the submodule. This also
prevents testing of the functionality in this patch by user-facing
commands. So for now, test this mechanism using a test helper.
Besides that, there is some code that uses the wrapper functions
like has_promisor_remote(). Those will need to be checked to see if they
could support the non-wrapper functions instead (and thus support any
repository, not just the_repository).
Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Reviewed-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In some test-cases, UTF-8 locale is required. To find such locale,
we're using the first available UTF-8 locale that returned by
"locale -a".
However, the locale(1) utility is unavailable on some systems,
e.g. Linux with musl libc.
However, without "locale -a", we can't guess provided UTF-8 locale.
Add a Makefile knob GIT_TEST_UTF8_LOCALE and activate it for
linux-musl in our CI system.
Rename t/lib-git-svn.sh:prepare_a_utf8_locale to prepare_utf8_locale,
since we no longer prepare the variable named "a_utf8_locale",
but set up a fallback value for GIT_TEST_UTF8_LOCALE instead.
The fallback will be LC_ALL, LANG environment variable,
or the first UTF-8 locale from output of "locale -a", in that order.
Signed-off-by: Đoàn Trần Công Danh <congdanhqx@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The "simple-ipc" did not compile without pthreads support, but the
build procedure was not properly account for it.
* jh/simple-ipc-sans-pthread:
simple-ipc: correct ifdefs when NO_PTHREADS is defined
Simple IPC always requires threads (in addition to various
platform-specific IPC support). Fix the ifdefs in the Makefile
to define SUPPORTS_SIMPLE_IPC when appropriate.
Previously, the Unix version of the code would only verify that
Unix domain sockets were available.
This problem was reported here:
https://lore.kernel.org/git/YKN5lXs4AoK%2FJFTO@coredump.intra.peff.net/T/#m08be8f1942ea8a2c36cfee0e51cdf06489fdeafc
Reported-by: Randall S. Becker <rsbecker@nexbridge.com>
Helped-by: Jeff King <peff@peff.net>
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Over-the-wire protocol learns a new request type to ask for object
sizes given a list of object names.
* ba/object-info:
object-info: support for retrieving object info
Since 07d90eadb5 (Makefile: add Perl runtime prefix support,
2018-04-10) PERL_DEFINES has been a simply-expanded variable, let's
make it recursively expanded instead.
This change doesn't matter for the correctness of the logic. Whether
we used simply-expanded or recursively expanded didn't change what we
wrote out in GIT-PERL-DEFINES, but being consistent with other rules
makes this easier to understand.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Change the logic of the i18n functions I added in 5e9637c629 (i18n:
add infrastructure for translating Git with gettext, 2011-11-18) to
use pass-through functions when NO_GETTEXT is defined.
This speeds up the compilation time of commands that use this library
when NO_GETTEXT=Y is in effect. Loading it and POSIX.pm is around 20ms
on my machine, whereas it takes 2ms to just instantiate perl itself.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Regenerate the *.pm files in perl/build/* if the
NO_PERL_CPAN_FALLBACKS flag added to the *.pm files in
1aca69c019 (perl Git::LoadCPAN: emit better errors under
NO_PERL_CPAN_FALLBACKS, 2018-03-03) is changed.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Change the logic to generate perl/build/* to regenerate those files if
GIT-PERL-DEFINES changes. This ensures that e.g. changing localedir
will result in correctly re-generated files.
I don't think that ever worked. The brokenness pre-dates my
20d2a30f8f (Makefile: replace perl/Makefile.PL with simple make
rules, 2017-12-10).
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Since 07d90eadb5 (Makefile: add Perl runtime prefix support,
2018-04-10) we have been declaring PERL_DEFINES right after assigning
to it, with the effect that the first PERL_DEFINES was ignored.
That bug didn't matter in practice since the first line had all the
same variables as the second, so we'd correctly re-generate
everything. It just made for confusing reading.
Let's remove that first assignment, and while we're at it split these
across lines to make them more maintainable.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The checkout machinery has been taught to perform the actual
write-out of the files in parallel when able.
* mt/parallel-checkout-part-2:
parallel-checkout: add design documentation
parallel-checkout: support progress displaying
parallel-checkout: add configuration options
parallel-checkout: make it truly parallel
unpack-trees: add basic support for parallel checkout
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
...
Sometimes it is useful to get information of an object without having to
download it completely.
Add the "object-info" capability that lets the client ask for
object-related information with their full hexadecimal object names.
Only sizes are returned for now.
Signed-off-by: Bruno Albuquerque <bga@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The dependencies for config-list.h and command-list.h were broken
when the former was split out of the latter, which has been
corrected.
* sg/bugreport-fixes:
Makefile: add missing dependencies of 'config-list.h'
A bit of code clean-up and a lot of test clean-up around userdiff
area.
* ab/userdiff-tests:
blame tests: simplify userdiff driver test
blame tests: don't rely on t/t4018/ directory
userdiff: remove support for "broken" tests
userdiff tests: list builtin drivers via test-tool
userdiff tests: explicitly test "default" pattern
userdiff: add and use for_each_userdiff_driver()
userdiff style: normalize pascal regex declaration
userdiff style: declare patterns with consistent style
userdiff style: re-order drivers in alphabetical order
Use multiple worker processes to distribute the queued entries and call
write_pc_item() in parallel for them. The items are distributed
uniformly in contiguous chunks. This minimizes the chances of two
workers writing to the same directory simultaneously, which could affect
performance due to lock contention in the kernel. Work stealing (or any
other format of re-distribution) is not implemented yet.
The protocol between the main process and the workers is quite simple.
They exchange binary messages packed in pkt-line format, and use
PKT-FLUSH to mark the end of input (from both sides). The main process
starts the communication by sending N pkt-lines, each corresponding to
an item that needs to be written. These packets contain all the
necessary information to load, smudge, and write the blob associated
with each item. Then it waits for the worker to send back N pkt-lines
containing the results for each item. The resulting packet must contain:
the identification number of the item that it refers to, the status of
the operation, and the lstat() data gathered after writing the file (iff
the operation was successful).
For now, checkout always uses a hardcoded value of 2 workers, only to
demonstrate that the parallel checkout framework correctly divides and
writes the queued entries. The next patch will add user configurations
and define a more reasonable default, based on tests with the said
settings.
Co-authored-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Co-authored-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Matheus Tavares <matheus.bernardino@usp.br>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This new interface allows us to enqueue some of the entries being
checked out to later uncompress them, apply in-process filters, and
write out the files in parallel. For now, the parallel checkout
machinery is enabled by default and there is no user configuration, but
run_parallel_checkout() just writes the queued entries in sequence
(without spawning additional workers). The next patch will actually
implement the parallelism and, later, we will make it configurable.
Note that, to avoid potential data races, not all entries are eligible
for parallel checkout. Also, paths that collide on disk (e.g.
case-sensitive paths in case-insensitive file systems), are detected by
the parallel checkout code and skipped, so that they can be safely
sequentially handled later. The collision detection works like the
following:
- If the collision was at basename (e.g. 'a/b' and 'a/B'), the framework
detects it by looking for EEXIST and EISDIR errors after an
open(O_CREAT | O_EXCL) failure.
- If the collision was at dirname (e.g. 'a/b' and 'A'), it is detected
at the has_dirs_only_path() check, which is done for the leading path
of each item in the parallel checkout queue.
Both verifications rely on the fact that, before enqueueing an entry for
parallel checkout, checkout_entry() makes sure that there is no file at
the entry's path and that its leading components are all real
directories. So, any later change in these conditions indicates that
there was a collision (either between two parallel-eligible entries or
between an eligible and an ineligible one).
After all parallel-eligible entries have been processed, the collided
(and thus, skipped) entries are sequentially fed to checkout_entry()
again. This is similar to the way the current code deals with
collisions, overwriting the previously checked out entries with the
subsequent ones. The only difference is that, since we no longer create
the files in the same order that they appear on index, we are not able
to determine which of the colliding entries will survive on disk (for
the classic code, it is always the last entry).
Co-authored-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Co-authored-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Matheus Tavares <matheus.bernardino@usp.br>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
A configuration variable has been added to force tips of certain
refs to be given a reachability bitmap.
* tb/pack-preferred-tips-to-give-bitmap:
builtin/pack-objects.c: respect 'pack.preferBitmapTips'
t/helper/test-bitmap.c: initial commit
pack-bitmap: add 'test_bitmap_commits()' helper
We auto-generate the list of supported configuration variables from
'Documentation/config/*.txt', and that list used to be created by the
'generate-cmdlist.sh' helper script and stored in the 'command-list.h'
header. Commit 709df95b78 (help: move list_config_help to
builtin/help, 2020-04-16) extracted this into a dedicated
'generate-configlist.sh' script and 'config-list.h' header, and added
a new target in the 'Makefile' as well, but while doing so it forgot
to extract the dependencies of the latter. Consequently, since then
'config-list.h' is not re-generated when 'Documentation/config/*.txt'
is updated, while 'command-list.h' is re-generated unnecessarily:
$ touch Documentation/config/log.txt
$ make -j4
GEN command-list.h
CC help.o
AR libgit.a
Fix this and list all config-related documentation files as
dependencies of 'config-list.h' and remove them from the dependencies
of 'command-list.h'.
$ touch Documentation/config/log.txt
$ make
GEN config-list.h
CC builtin/help.o
LINK git
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Change the userdiff test to list the builtin drivers via the
test-tool, using the new for_each_userdiff_driver() API function.
This gets rid of the need to modify this part of the test every time a
new pattern is added, see 2ff6c34612 (userdiff: support Bash,
2020-10-22) and 09dad9256a (userdiff: support Markdown, 2020-05-02)
for two recent examples.
I only need the "list-builtin-drivers "argument here, but let's add
"list-custom-drivers" and "list-drivers" too, just because it's easy.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
A simple IPC interface gets introduced to build services like
fsmonitor on top.
* jh/simple-ipc:
t0052: add simple-ipc tests and t/helper/test-simple-ipc tool
simple-ipc: add Unix domain socket implementation
unix-stream-server: create unix domain socket under lock
unix-socket: disallow chdir() when creating unix domain sockets
unix-socket: add backlog size option to unix_stream_listen()
unix-socket: eliminate static unix_stream_socket() helper function
simple-ipc: add win32 implementation
simple-ipc: design documentation for new IPC mechanism
pkt-line: add options argument to read_packetized_to_strbuf()
pkt-line: add PACKET_READ_GENTLE_ON_READ_ERROR option
pkt-line: do not issue flush packets in write_packetized_*()
pkt-line: eliminate the need for static buffer in packet_write_gently()
Don't show the very verbose $(FIND_SOURCE_FILES) command on every
"make TAGS" invocation.
Let's use "generate into temporary and rename to the final file,
after seeing the command that generated the output finished
successfully" pattern, to avoid leaving a file with an incorrect
output generated by a failed command.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add a new 'bitmap' test-tool which can be used to list the commits that
have received bitmaps.
In theory, a determined tester could run 'git rev-list --test-bitmap
<commit>' to check if '<commit>' received a bitmap or not, since
'--test-bitmap' exits with a non-zero code when it can't find the
requested commit.
But this is a dubious behavior to rely on, since arguably 'git
rev-list' could continue its object walk outside of which commits are
covered by bitmaps.
This will be used to test the behavior of 'pack.preferBitmapTips', which
will be added in the following patch.
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Upcoming changes will introduce modifications to the index format that
allow sparse directories. It will be useful to have a mechanism for
converting those sparse index files into full indexes by walking the
tree at those sparse directories. Name this method ensure_full_index()
as it will guarantee that the index is fully expanded.
This method is not implemented yet, and instead we focus on the
scaffolding to declare it and call it at the appropriate time.
Add a 'command_requires_full_index' member to struct repo_settings. This
will be an indicator that we need the index in full mode to do certain
index operations. This starts as being true for every command, then we
will set it to false as some commands integrate with sparse indexes.
If 'command_requires_full_index' is true, then we will immediately
expand a sparse index to a full one upon reading from disk. This
suffices for now, but we will want to add more callers to
ensure_full_index() later.
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Reorganize Makefile to allow building git.o and other essential
objects without extra stuff needed only for testing.
* ab/make-cleanup:
Makefile: add {program,xdiff,test,git,fuzz}-objs & objects targets
Makefile: split OBJECTS into OBJECTS and GIT_OBJS
Makefile: sort OBJECTS assignment for subsequent change
Makefile: split up long OBJECTS line
Makefile: guard against TEST_OBJS in the environment
Create t0052-simple-ipc.sh with unit tests for the "simple-ipc" mechanism.
Create t/helper/test-simple-ipc test tool to exercise the "simple-ipc"
functions.
When the tool is invoked with "run-daemon", it runs a server to listen
for "simple-ipc" connections on a test socket or named pipe and
responds to a set of commands to exercise/stress the communication
setup.
When the tool is invoked with "start-daemon", it spawns a "run-daemon"
command in the background and waits for the server to become ready
before exiting. (This helps make unit tests in t0052 more predictable
and avoids the need for arbitrary sleeps in the test script.)
The tool also has a series of client "send" commands to send commands
and data to a server instance.
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Create Unix domain socket based implementation of "simple-ipc".
A set of `ipc_client` routines implement a client library to connect
to an `ipc_server` over a Unix domain socket, send a simple request,
and receive a single response. Clients use blocking IO on the socket.
A set of `ipc_server` routines implement a thread pool to listen for
and concurrently service client connections.
The server creates a new Unix domain socket at a known location. If a
socket already exists with that name, the server tries to determine if
another server is already listening on the socket or if the socket is
dead. If socket is busy, the server exits with an error rather than
stealing the socket. If the socket is dead, the server creates a new
one and starts up.
If while running, the server detects that its socket has been stolen
by another server, it automatically exits.
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Create a wrapper class for `unix_stream_listen()` that uses a ".lock"
lockfile to create the unix domain socket in a race-free manner.
Unix domain sockets have a fundamental problem on Unix systems because
they persist in the filesystem until they are deleted. This is
independent of whether a server is actually listening for connections.
Well-behaved servers are expected to delete the socket when they
shutdown. A new server cannot easily tell if a found socket is
attached to an active server or is leftover cruft from a dead server.
The traditional solution used by `unix_stream_listen()` is to force
delete the socket pathname and then create a new socket. This solves
the latter (cruft) problem, but in the case of the former, it orphans
the existing server (by stealing the pathname associated with the
socket it is listening on).
We cannot directly use a .lock lockfile to create the socket because
the socket is created by `bind(2)` rather than the `open(2)` mechanism
used by `tempfile.c`.
As an alternative, we hold a plain lockfile ("<path>.lock") as a
mutual exclusion device. Under the lock, we test if an existing
socket ("<path>") is has an active server. If not, we create a new
socket and begin listening. Then we use "rollback" to delete the
lockfile in all cases.
This wrapper code conceptually exists at a higher-level than the core
unix_stream_connect() and unix_stream_listen() routines that it
consumes. It is isolated in a wrapper class for clarity.
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Create Windows implementation of "simple-ipc" using named pipes.
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Clang no longer produces a libFuzzer.a. Instead, you can include
libFuzzer by using -fsanitize=fuzzer. Therefore we should use that in
the example command for building fuzzers.
We also add -fsanitize=fuzzer-no-link to the CFLAGS to ensure that all
the required instrumentation is added when compiling git [1], and remove
-fsanitize-coverage=trace-pc-guard as it is deprecated.
I happen to have tested with LLVM 11 - however -fsanitize=fuzzer appears
to work in a wide range of reasonably modern clangs.
(On my system: what used to be libFuzzer.a now lives under the following
path, which is tricky albeit not impossible for a novice such as myself
to find:
/usr/lib64/clang/11.0.0/lib/linux/libclang_rt.fuzzer-x86_64.a )
[1] https://releases.llvm.org/11.0.0/docs/LibFuzzer.html#fuzzer-usage
Signed-off-by: Andrzej Hunt <ajrhunt@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Work around platforms whose open() is reported to return EINTR (it
shouldn't, as we do our signals with SA_RESTART).
* jk/open-returns-eintr:
config.mak.uname: enable OPEN_RETURNS_EINTR for macOS Big Sur
Makefile: add OPEN_RETURNS_EINTR knob
The common code to deal with "chunked file format" that is shared
by the multi-pack-index and commit-graph files have been factored
out, to help codepaths for both filetypes to become more robust.
* ds/chunked-file-api:
commit-graph.c: display correct number of chunks when writing
chunk-format: add technical docs
chunk-format: restore duplicate chunk checks
midx: use 64-bit multiplication for chunk sizes
midx: use chunk-format read API
commit-graph: use chunk-format read API
chunk-format: create read chunk API
midx: use chunk-format API in write_midx_internal()
midx: drop chunk progress during write
midx: return success/failure in chunk write methods
midx: add num_large_offsets to write_midx_context
midx: add pack_perm to write_midx_context
midx: add entries to write_midx_context
midx: use context in write_midx_pack_names()
midx: rename pack_info to write_midx_context
commit-graph: use chunk-format write API
chunk-format: create chunk format write API
commit-graph: anonymize data in chunk_write_fn
On some platforms, open() reportedly returns EINTR when opening regular
files and we receive a signal (usually SIGALRM from our progress meter).
This shouldn't happen, as open() should be a restartable syscall, and we
specify SA_RESTART when setting up the alarm handler. So it may actually
be a kernel or libc bug for this to happen. But it has been reported on
at least one version of Linux (on a network filesystem):
https://lore.kernel.org/git/c8061cce-71e4-17bd-a56a-a5fed93804da@neanderfunk.de/
as well as on macOS starting with Big Sur even on a regular filesystem.
We can work around it by retrying open() calls that get EINTR, just as
we do for read(), etc. Since we don't ever _want_ to interrupt an open()
call, we can get away with just redefining open, rather than insisting
all callsites use xopen().
We actually do have an xopen() wrapper already (and it even does this
retry, though there's no indication of it being an observed problem back
then; it seems simply to have been lifted from xread(), etc). But it is
used hardly anywhere, and isn't suitable for general use because it will
die() on error. In theory we could combine the two, but it's awkward to
do so because of the variable-args interface of open().
This patch adds a Makefile knob for enabling the workaround. It's not
enabled by default for any platforms in config.mak.uname yet, as we
don't have enough data to decide how common this is (I have not been
able to reproduce on either Linux or Big Sur myself). It may be worth
enabling preemptively anyway, since the cost is pretty low (if we don't
see an EINTR, it's just an extra conditional).
However, note that we must not enable this on Windows. It doesn't do
anything there, and the macro overrides the existing mingw_open()
redirection. I've added a preemptive #undef here in the mingw header
(which is processed first) to just quietly disable it (we could also
make it an #error, but there is little point in being so aggressive).
Reported-by: Aleksey Kliger <alklig@microsoft.com>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
