Replace core.fsyncObjectFiles with two new configuration variables,
core.fsync and core.fsyncMethod.
* ns/core-fsyncmethod:
core.fsync: documentation and user-friendly aggregate options
core.fsync: new option to harden the index
core.fsync: add configuration parsing
core.fsync: introduce granular fsync control infrastructure
core.fsyncmethod: add writeout-only mode
wrapper: make inclusion of Windows csprng header tightly scoped
"git stash drop" is reimplemented as an internal call to
reflog_delete() function, instead of invoking "git reflog delete"
via run_command() API.
* jc/stash-drop:
stash: call reflog_delete() in reflog.c
reflog: libify delete reflog function and helpers
stash: add tests to ensure reflog --rewrite --updatref behavior
This commit introduces the `core.fsyncMethod` configuration
knob, which can currently be set to `fsync` or `writeout-only`.
The new writeout-only mode attempts to tell the operating system to
flush its in-memory page cache to the storage hardware without issuing a
CACHE_FLUSH command to the storage controller.
Writeout-only fsync is significantly faster than a vanilla fsync on
common hardware, since data is written to a disk-side cache rather than
all the way to a durable medium. Later changes in this patch series will
take advantage of this primitive to implement batching of hardware
flushes.
When git_fsync is called with FSYNC_WRITEOUT_ONLY, it may fail and the
caller is expected to do an ordinary fsync as needed.
On Apple platforms, the fsync system call does not issue a CACHE_FLUSH
directive to the storage controller. This change updates fsync to do
fcntl(F_FULLFSYNC) to make fsync actually durable. We maintain parity
with existing behavior on Apple platforms by setting the default value
of the new core.fsyncMethod option.
Signed-off-by: Neeraj Singh <neerajsi@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add a template to do the "mkdir -p" of $(@D) (the parent dir of $@)
for us, and use it for the "make lint-docs" targets I added in
8650c6298c (doc lint: make "lint-docs" non-.PHONY, 2021-10-15).
As seen in 4c64fb5aad (Documentation/Makefile: fix lint-docs mkdir
dependency, 2021-10-26) maintaining these manual lists of parent
directory dependencies is fragile, in addition to being obviously
verbose.
I used this pattern at the time because I couldn't find another method
than "order-only" prerequisites to avoid doing a "mkdir -p $(@D)" for
every file being created, which as noted in [1] would be significantly
slower.
But as it turns out we can use this neat trick of only doing a "mkdir
-p" if the $(wildcard) macro tells us the path doesn't exist. A re-run
of a performance test similar to that noted downthread of [1] in [2]
shows that this is faster, in addition to being less verbose and more
reliable (this uses my "git-hyperfine" thin wrapper for "hyperfine"[3]):
$ git -c hyperfine.hook.setup= hyperfine -L rev HEAD~1,HEAD~0 -s 'make -C Documentation lint-docs' -p 'rm -rf Documentation/.build' 'make -C Documentation -j1 lint-docs'
Benchmark 1: make -C Documentation -j1 lint-docs' in 'HEAD~1
Time (mean ± σ): 2.914 s ± 0.062 s [User: 2.449 s, System: 0.489 s]
Range (min … max): 2.834 s … 3.020 s 10 runs
Benchmark 2: make -C Documentation -j1 lint-docs' in 'HEAD~0
Time (mean ± σ): 2.315 s ± 0.062 s [User: 1.950 s, System: 0.386 s]
Range (min … max): 2.229 s … 2.397 s 10 runs
Summary
'make -C Documentation -j1 lint-docs' in 'HEAD~0' ran
1.26 ± 0.04 times faster than 'make -C Documentation -j1 lint-docs' in 'HEAD~1'
So let's use that pattern both for the "lint-docs" target, and a few
miscellaneous other targets.
This method of creating parent directories is explicitly racy in that
we don't know if we're going to say always create a "foo" followed by
a "foo/bar" under parallelism, or skip the "foo" because we created
"foo/bar" first. In this case it doesn't matter for anything except
that we aren't guaranteed to get the same number of rules firing when
running make in parallel.
1. https://lore.kernel.org/git/211028.861r45y3pt.gmgdl@evledraar.gmail.com/
2. https://lore.kernel.org/git/211028.86o879vvtp.gmgdl@evledraar.gmail.com/
3. https://gitlab.com/avar/git-hyperfine/
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The $(QUIET) variables we define are largely duplicated between our
various Makefiles, let's define them in the new "shared.mak" instead.
Since we're not using the environment to pass these around we don't
need to export the "QUIET_GEN" and "QUIET_BUILT_IN" variables
anymore. The "QUIET_GEN" variable is used in "git-gui/Makefile" and
"gitweb/Makefile", but they've got their own definition for those. The
"QUIET_BUILT_IN" variable is only used in the top-level "Makefile". We
still need to export the "V" variable.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Move these variables over to the shared.mak, we'll make use of them in
a subsequent commit.
Note that there's reason for these to be "simply expanded variables",
i.e. to use ":=" assignments instead of lazily expanded "="
assignments. We could use "=", but let's leave this as-is for now for
ease of review.
See 425ca6710b (Makefile: allow combining UBSan with other
sanitizers, 2017-07-15) for the commit that introduced these.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This was added in 30248886ce (Makefile: disable default implicit
rules, 2010-01-26), let's move it to the top of "shared.mak" so it'll
apply to all our Makefiles.
This doesn't benefit the main Makefile at all, since it already had
the rule, but since we're including shared.mak in other Makefiles
starts to benefit them. E.g. running the 'man" target is now faster:
$ git -c hyperfine.hook.setup= hyperfine -L rev HEAD~1,HEAD~0 -s 'make -C Documentation man' 'make -C Documentation -j1 man'
Benchmark 1: make -C Documentation -j1 man' in 'HEAD~1
Time (mean ± σ): 121.7 ms ± 8.8 ms [User: 105.8 ms, System: 18.6 ms]
Range (min … max): 112.8 ms … 148.4 ms 26 runs
Benchmark 2: make -C Documentation -j1 man' in 'HEAD~0
Time (mean ± σ): 97.5 ms ± 8.0 ms [User: 80.1 ms, System: 20.1 ms]
Range (min … max): 89.8 ms … 111.8 ms 32 runs
Summary
'make -C Documentation -j1 man' in 'HEAD~0' ran
1.25 ± 0.14 times faster than 'make -C Documentation -j1 man' in 'HEAD~1'
The reason for that can be seen when comparing that run with
"--debug=a". Without this change making a target like "git-status.1"
will cause "make" to consider not only "git-status.txt", but
"git-status.txt.o", as well as numerous other implicit suffixes such
as ".c", ".cc", ".cpp" etc. See [1] for a more detailed before/after
example.
So this is causing us to omit a bunch of work we didn't need to
do. For making "git-status.1" the "--debug=a" output is reduced from
~140k lines to ~6k.
1. https://lore.kernel.org/git/220222.86bkyz875k.gmgdl@evledraar.gmail.com/
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Combine the definitions of $(FIND_SOURCE_FILES) and $(LIB_H) to speed
up the Makefile, as these are the two main expensive $(shell) commands
that we execute unconditionally.
When see what was in $(FOUND_SOURCE_FILES) that wasn't in $(LIB_H) via
the ad-hoc test of:
$(error $(filter-out $(LIB_H),$(filter %.h,$(ALL_SOURCE_FILES))))
$(error $(filter-out $(ALL_SOURCE_FILES),$(filter %.h,$(LIB_H))))
We'll get, respectively:
Makefile:850: *** t/helper/test-tool.h. Stop.
Makefile:850: *** . Stop.
I.e. we only had a discrepancy when it came to
t/helper/test-tool.h. In terms of correctness this was broken before,
but now works:
$ make t/helper/test-tool.hco
HDR t/helper/test-tool.h
This speeds things up a lot:
$ git -c hyperfine.hook.setup= hyperfine -L rev HEAD~1,HEAD~0 -s 'make NO_TCLTK=Y' 'make -j1 NO_TCLTK=Y' --warmup 10 -M 10
Benchmark 1: make -j1 NO_TCLTK=Y' in 'HEAD~1
Time (mean ± σ): 159.9 ms ± 6.8 ms [User: 137.2 ms, System: 28.0 ms]
Range (min … max): 154.6 ms … 175.9 ms 10 runs
Benchmark 2: make -j1 NO_TCLTK=Y' in 'HEAD~0
Time (mean ± σ): 100.0 ms ± 1.3 ms [User: 84.2 ms, System: 20.2 ms]
Range (min … max): 98.8 ms … 102.8 ms 10 runs
Summary
'make -j1 NO_TCLTK=Y' in 'HEAD~0' ran
1.60 ± 0.07 times faster than 'make -j1 NO_TCLTK=Y' in 'HEAD~1'
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We have various behavior that's shared across our Makefiles, or that
really should be (e.g. via defined templates). Let's create a
top-level "shared.mak" to house those sorts of things, and start by
adding the ".DELETE_ON_ERROR" flag to it.
See my own 7b76d6bf22 (Makefile: add and use the ".DELETE_ON_ERROR"
flag, 2021-06-29) and db10fc6c09 (doc: simplify Makefile using
.DELETE_ON_ERROR, 2021-05-21) for the addition and use of the
".DELETE_ON_ERROR" flag.
I.e. this changes the behavior of existing rules in the altered
Makefiles (except "Makefile" & "Documentation/Makefile"). I'm
confident that this is safe having read the relevant rules in those
Makfiles, and as the GNU make manual notes that it isn't the default
behavior is out of an abundance of backwards compatibility
caution. From edition 0.75 of its manual, covering GNU make 4.3:
[Enabling '.DELETE_ON_ERROR' is] almost always what you want
'make' to do, but it is not historical practice; so for
compatibility, you must explicitly request it.
This doesn't introduce a bug by e.g. having this
".DELETE_ON_ERROR" flag only apply to this new shared.mak, Makefiles
have no such scoping semantics.
It does increase the danger that any Makefile without an explicit "The
default target of this Makefile is..." snippet to define the default
target as "all" could have its default rule changed if our new
shared.mak ever defines a "real" rule. In subsequent commits we'll be
careful not to do that, and such breakage would be obvious e.g. in the
case of "make -C t".
We might want to make that less fragile still (e.g. by using
".DEFAULT_GOAL" as noted in the preceding commit), but for now let's
simply include "shared.mak" without adding that boilerplate to all the
Makefiles that don't have it already. Most of those are already
exposed to that potential caveat e.g. due to including "config.mak*".
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Currently stash shells out to reflog in order to delete refs. In an
effort to reduce how much we shell out to a subprocess, libify the
functionality that stash needs into reflog.c.
Add a reflog_delete function that is pretty much the logic in the while
loop in builtin/reflog.c cmd_reflog_delete(). This is a function that
builtin/reflog.c and builtin/stash.c can both call.
Also move functions needed by reflog_delete and export them.
Helped-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: John Cai <johncai86@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The build procedure has been taught to notice older version of zlib
and enable our replacement uncompress2() automatically.
* ab/auto-detect-zlib-compress2:
compat: auto-detect if zlib has uncompress2()
Pick a better random number generator and use it when we prepare
temporary filenames.
* bc/csprng-mktemps:
wrapper: use a CSPRNG to generate random file names
wrapper: add a helper to generate numbers from a CSPRNG
More "config-based hooks".
* ab/config-based-hooks-2:
run-command: remove old run_hook_{le,ve}() hook API
receive-pack: convert push-to-checkout hook to hook.h
read-cache: convert post-index-change to use hook.h
commit: convert {pre-commit,prepare-commit-msg} hook to hook.h
git-p4: use 'git hook' to run hooks
send-email: use 'git hook run' for 'sendemail-validate'
git hook run: add an --ignore-missing flag
hooks: convert worktree 'post-checkout' hook to hook library
hooks: convert non-worktree 'post-checkout' hook to hook library
merge: convert post-merge to use hook.h
am: convert applypatch-msg to use hook.h
rebase: convert pre-rebase to use hook.h
hook API: add a run_hooks_l() wrapper
am: convert {pre,post}-applypatch to use hook.h
gc: use hook library for pre-auto-gc hook
hook API: add a run_hooks() wrapper
hook: add 'run' subcommand
We have a copy of uncompress2() implementation in compat/ so that we
can build with an older version of zlib that lack the function, and
the build procedure selects if it is used via the NO_UNCOMPRESS2
$(MAKE) variable. This is yet another "annoying" knob the porters
need to tweak on platforms that are not common enough to have the
default set in the config.mak.uname file.
Attempt to instead ask the system header <zlib.h> to decide if we
need the compatibility implementation. This is a deviation from the
way we have been handling the "compatiblity" features so far, and if
it can be done cleanly enough, it could work as a model for features
that need compatibility definition we discover in the future. With
that goal in mind, avoid expedient but ugly hacks, like shoving the
code that is conditionally compiled into an unrelated .c file, which
may not work in future cases---instead, take an approach that uses a
file that is independently compiled and stands on its own.
Compile and link compat/zlib-uncompress2.c file unconditionally, but
conditionally hide the implementation behind #if/#endif when zlib
version is 1.2.9 or newer, and unconditionally archive the resulting
object file in the libgit.a to be picked up by the linker.
There are a few things to note in the shape of the code base after
this change:
- We no longer use NO_UNCOMPRESS2 knob; if the system header
<zlib.h> claims a version that is more cent than the library
actually is, this would break, but it is easy to add it back when
we find such a system.
- The object file compat/zlib-uncompress2.o is always compiled and
archived in libgit.a, just like a few other compat/ object files
already are.
- The inclusion of <zlib.h> is done in <git-compat-util.h>; we used
to do so from <cache.h> which includes <git-compat-util.h> as the
first thing it does, so from the *.c codes, there is no practical
change.
- Until objects in libgit.a that is already used gains a reference
to the function, the reftable code will be the only one that
wants it, so libgit.a on the linker command line needs to appear
once more at the end to satisify the mutual dependency.
- Beat found a trick used by OpenSSL to avoid making the
conditionally-compiled object truly empty (apparently because
they had to deal with compilers that do not want to see an
effectively empty input file). Our compat/zlib-uncompress2.c
file borrows the same trick for portabilty.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Helped-by: Beat Bolli <dev+git@drbeat.li>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
There are many situations in which having access to a cryptographically
secure pseudorandom number generator (CSPRNG) is helpful. In the
future, we'll encounter one of these when dealing with temporary files.
To make this possible, let's add a function which reads from a system
CSPRNG and returns some bytes.
We know that all systems will have such an interface. A CSPRNG is
required for a secure TLS or SSH implementation and a Git implementation
which provided neither would be of little practical use. In addition,
POSIX is set to standardize getentropy(2) in the next version, so in the
(potentially distant) future we can rely on that.
For systems which lack one of the other interfaces, we provide the
ability to use OpenSSL's CSPRNG. OpenSSL is highly portable and
functions on practically every known OS, and we know it will have access
to some source of cryptographically secure randomness. We also provide
support for the arc4random in libbsd for folks who would prefer to use
that.
Because this is a security sensitive interface, we take some
precautions. We either succeed by filling the buffer completely as we
requested, or we fail. We don't return partial data because the caller
will almost never find that to be a useful behavior.
Specify a makefile knob which users can use to specify one or more
suitable CSPRNGs, and turn the multiple string options into a set of
defines, since we cannot match on strings in the preprocessor. We allow
multiple options to make the job of handling this in autoconf easier.
The order of options is important here. On systems with arc4random,
which is most of the BSDs, we use that, since, except on MirBSD and
macOS, it uses ChaCha20, which is extremely fast, and sits entirely in
userspace, avoiding a system call. We then prefer getrandom over
getentropy, because the former has been available longer on Linux, and
then OpenSSL. Finally, if none of those are available, we use
/dev/urandom, because most Unix-like operating systems provide that API.
We prefer options that don't involve device files when possible because
those work in some restricted environments where device files may not be
available.
Set the configuration variables appropriately for Linux and the BSDs,
including macOS, as well as Windows and NonStop. We specifically only
consider versions which receive publicly available security support
here. For the same reason, we don't specify getrandom(2) on Linux,
because CentOS 7 doesn't support it in glibc (although its kernel does)
and we don't want to resort to making syscalls.
Finally, add a test helper to allow this to be tested by hand and in
tests. We don't add any tests, since invoking the CSPRNG is not likely
to produce interesting, reproducible results.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In order to enable hooks to be run as an external process, by a
standalone Git command, or by tools which wrap Git, provide an external
means to run all configured hook commands for a given hook event.
Most of our hooks require more complex functionality than this, but
let's start with the bare minimum required to support our simplest
hooks.
In terms of implementation the usage_with_options() and "goto usage"
pattern here mirrors that of
builtin/{commit-graph,multi-pack-index}.c.
Some of the implementation here, such as a function being named
run_hooks_opt() when it's tasked with running one hook, to using the
run_processes_parallel_tr2() API to run with jobs=1 is somewhere
between a bit odd and and an overkill for the current features of this
"hook run" command and the hook.[ch] API.
This code will eventually be able to run multiple hooks declared in
config in parallel, by starting out with these names and APIs we
reduce the later churn of renaming functions, switching from the
run_command() to run_processes_parallel_tr2() API etc.
Signed-off-by: Emily Shaffer <emilyshaffer@google.com>
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Acked-by: Emily Shaffer <emilyshaffer@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Remove the --statistics flag that I added in 5e9637c629 (i18n: add
infrastructure for translating Git with gettext, 2011-11-18). Our
Makefile output is good about reducing verbosity by default, except in
this case:
$ rm -rf po/build/locale/e*; time make -j $(nproc) all
SUBDIR templates
MKDIR -p po/build/locale/el/LC_MESSAGES
MSGFMT po/build/locale/el/LC_MESSAGES/git.mo
MKDIR -p po/build/locale/es/LC_MESSAGES
MSGFMT po/build/locale/es/LC_MESSAGES/git.mo
1038 translated messages, 3325 untranslated messages.
5230 translated messages.
I didn't have any good reason for using --statistics at the time other
than ad-hoc eyeballing of the output. We don't need to spew out
exactly how many messages we've got translated every time. Now we'll
instead emit:
$ rm -rf po/build/locale/e*; time make -j $(nproc) all
SUBDIR templates
MKDIR -p po/build/locale/el/LC_MESSAGES
MSGFMT po/build/locale/el/LC_MESSAGES/git.mo
MKDIR -p po/build/locale/es/LC_MESSAGES
MSGFMT po/build/locale/es/LC_MESSAGES/git.mo
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Remove -DPAGER_ENV from the BASIC_CFLAGS and instead have it passed
via the EXTRA_CPPFLAGS passed when compiling pager.c.
This doesn't change anything except to make it clear that only pager.c
needs this, as it's the only user of this define. See
995bc22d7f (pager: move pager-specific setup into the build,
2016-08-04) for the commit that originally added this.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Fix an issue in my cfe853e66b (hook-list.h: add a generated list of
hooks, like config-list.h, 2021-09-26), the builtin/help.c was
inadvertently made to depend on hook-list.h, but it's used by
builtin/bugreport.c.
The hook.c also does not depend on hook-list.h. It did in an earlier
version of the greater series cfe853e66b was extracted from, but not
anymore. We might end up needing that line again, but let's remove it
for now.
Reported-by: Mike Hommey <mh@glandium.org>
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add pieces from "scalar" to contrib/.
* js/scalar:
scalar: implement the `version` command
scalar: implement the `delete` command
scalar: teach 'reconfigure' to optionally handle all registered enlistments
scalar: allow reconfiguring an existing enlistment
scalar: implement the `run` command
scalar: teach 'clone' to support the --single-branch option
scalar: implement the `clone` subcommand
scalar: implement 'scalar list'
scalar: let 'unregister' handle a deleted enlistment directory gracefully
scalar: 'unregister' stops background maintenance
scalar: 'register' sets recommended config and starts maintenance
scalar: create test infrastructure
scalar: start documenting the command
scalar: create a rudimentary executable
scalar: add a README with a roadmap
Weather balloon to find compilers that do not grok variable
declaration in the for() loop.
* jc/c99-var-decl-in-for-loop:
revision: use C99 declaration of variable in for() loop
The "reftable" backend for the refs API, without integrating into
the refs subsystem, has been added.
* hn/reftable:
Add "test-tool dump-reftable" command.
reftable: add dump utility
reftable: implement stack, a mutable database of reftable files.
reftable: implement refname validation
reftable: add merged table view
reftable: add a heap-based priority queue for reftable records
reftable: reftable file level tests
reftable: read reftable files
reftable: generic interface to tables
reftable: write reftable files
reftable: a generic binary tree implementation
reftable: reading/writing blocks
Provide zlib's uncompress2 from compat/zlib-compat.c
reftable: (de)serialization for the polymorphic record type.
reftable: add blocksource, an abstraction for random access reads
reftable: utility functions
reftable: add error related functionality
reftable: add LICENSE
hash.h: provide constants for the hash IDs
The idea of Scalar (https://github.com/microsoft/scalar), and before
that, of VFS for Git, has always been to prove that Git _can_ scale, and
to upstream whatever strategies have been demonstrated to help.
With this patch, we start the journey from that C# project to move what
is left to Git's own `contrib/` directory, reimplementing it in pure C,
with the intention to facilitate integrating the functionality into core
Git all while maintaining backwards-compatibility for existing Scalar
users (which will be much easier when both live in the same worktree).
It has always been the plan to contribute all of the proven strategies
back to core Git.
For example, while the virtual filesystem provided by VFS for Git helped
the team developing the Windows operating system to move onto Git, while
trying to upstream it we realized that it cannot be done: getting the
virtual filesystem to work (which we only managed to implement fully on
Windows, but not on, say, macOS or Linux), and the required server-side
support for the GVFS protocol, made this not quite feasible.
The Scalar project learned from that and tackled the problem with
different tactics: instead of pretending to Git that the working
directory is fully populated, it _specifically_ teaches Git about
partial clone (which is based on VFS for Git's cache server), about
sparse checkout (which VFS for Git tried to do transparently, in the
file system layer), and regularly runs maintenance tasks to keep the
repository in a healthy state.
With partial clone, sparse checkout and `git maintenance` having been
upstreamed, there is little left that `scalar.exe` does which `git.exe`
cannot do. One such thing is that `scalar clone <url>` will
automatically set up a partial, sparse clone, and configure
known-helpful settings from the start.
So let's bring this convenience into Git's tree.
The idea here is that you can (optionally) build Scalar via
make -C contrib/scalar/
This will build the `scalar` executable and put it into the
contrib/scalar/ subdirectory.
The slightly awkward addition of the `contrib/scalar/*` bits to the
top-level `Makefile` are actually really required: we want to link to
`libgit.a`, which means that we will need to use the very same `CFLAGS`
and `LDFLAGS` as the rest of Git.
An early development version of this patch tried to replicate all the
conditional code in `contrib/scalar/Makefile` (e.g. `NO_POLL`) just like
`contrib/svn-fe/Makefile` used to do before it was retired. It turned
out to be quite the whack-a-mole game: the SHA-1-related flags, the
flags enabling/disabling `compat/poll/`, `compat/regex/`,
`compat/win32mmap.c` & friends depending on the current platform... To
put it mildly: it was a major mess.
Instead, this patch makes minimal changes to the top-level `Makefile` so
that the bits in `contrib/scalar/` can be compiled and linked, and
adds a `contrib/scalar/Makefile` that uses the top-level `Makefile` in a
most minimal way to do the actual compiling.
Note: With this commit, we only establish the infrastructure, no
Scalar functionality is implemented yet; We will do that incrementally
over the next few commits.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
There are certain C99 features that might be nice to use in our code
base, but we've hesitated to do so in order to avoid breaking
compatibility with older compilers. But we don't actually know if
people are even using pre-C99 compilers these days.
One way to figure that out is to introduce a very small use of a
feature, and see if anybody complains, and we've done so to probe
the portability for a few features like "trailing comma in enum
declaration", "designated initializer for struct", and "designated
initializer for array". A few years ago, we tried to use a handy
for (int i = 0; i < n; i++)
use(i);
to introduce a new variable valid only in the loop, but found that
some compilers we cared about didn't like it back then. Two years
is a long-enough time, so let's try it again.
If this patch can survive a few releases without complaint, then we
can feel more confident that variable declaration in for() loop is
supported by the compilers our user base use. And if we do get
complaints, then we'll have gained some data and we can easily
revert this patch.
Helped-by: Martin Ågren <martin.agren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The C99 standard was released in January 1999, now 22 years ago. It
provides a variety of useful features, including variadic arguments for
macros, declarations after statements, designated initializers, and a
wide variety of other useful features, many of which we already use.
We'd like to take advantage of these features, but we want to be
cautious. As far as we know, all major compilers now support C99 or a
later C standard, such as C11 or C17. POSIX has required C99 support as
a requirement for the 2001 revision, so we can safely assume any POSIX
system which we are interested in supporting has C99.
Even MSVC, long a holdout against modern C, now supports both C11 and
C17 with an appropriate update. Moreover, even if people are using an
older version of MSVC on these systems, they will generally need some
implementation of the standard Unix utilities for the testsuite, and GNU
coreutils, the most common option, has required C99 since 2009.
Therefore, we can safely assume that a suitable version of GCC or clang
is available to users even if their version of MSVC is not sufficiently
capable.
Let's add a test balloon to git-compat-util.h to see if anyone is using
an older compiler. We'll add a comment telling people how to enable
this functionality on GCC and Clang, even though modern versions of both
will automatically do the right thing, and ask people still experiencing
a problem to report that to us on the list.
Note that C89 compilers don't provide the __STDC_VERSION__ macro, so we
use a well-known hack of using "- 0". On compilers with this macro, it
doesn't change the value, and on C89 compilers, the macro will be
replaced with nothing, and our value will be 0.
For sparse, we explicitly request the gnu99 style because we've
traditionally taken advantage of some GCC- and clang-specific extensions
when available and we'd like to retain the ability to do that. sparse
also defaults to C89 without it, so things will fail for us if we don't.
Update the cmake configuration to require C11 for MSVC. We do this
because this will make MSVC to use C11, since it does not explicitly
support C99. We do this with a compiler options because setting the
C_STANDARD option does not work in our CI on MSVC and at the moment, we
don't want to require C11 for Unix compilers.
In the Makefile, don't set any compiler flags for the compiler itself,
since on some systems, such as FreeBSD, we actually need C11, and asking
for C99 causes things to fail to compile. The error message should make
it obvious what's going wrong and allow a user to set the appropriate
option when building in the event they're using a Unix compiler that
doesn't support it by default.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Make a few helper functions unused and then lose them.
* ab/sh-retire-helper-functions:
git-sh-setup: remove "sane_grep", it's not needed anymore
git-sh-setup: remove unused sane_egrep() function
git-instaweb: unconditionally assume that gitweb is mod_perl capable
Makefile: remove $(NO_CURL) from $(SCRIPT_DEFINES)
Makefile: remove $(GIT_VERSION) from $(SCRIPT_DEFINES)
Makefile: move git-SCRIPT-DEFINES adjacent to $(SCRIPT_DEFINES)
The "sparse" target needed the GIT-CFLAGS dependency before my
c234e8a0ec (Makefile: make the "sparse" target non-.PHONY,
2021-09-23), but since then it depends on the corresponding *.o files,
which in turn depend on the correct header files, as well as on
GIT-CFLAGS. There's no need to re-state this dependency here.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Remove the sane_grep() shell function in git-sh-setup. The two reasons
for why it existed don't apply anymore:
1. It was added due to GNU grep supporting GREP_OPTIONS. See
e1622bfcba (Protect scripted Porcelains from GREP_OPTIONS insanity,
2009-11-23).
Newer versions of GNU grep ignore that, but even on older versions
its existence won't matter, none of these sane_grep() uses care
about grep's output, they're merely using it to check if a string
exists in a file or stream. We also don't care about the "LC_ALL=C"
that "sane_grep" was using, these greps for fixed or ASCII strings
will behave the same under any locale.
2. The SANE_TEXT_GREP added in 71b401032b (sane_grep: pass "-a" if
grep accepts it, 2016-03-08) isn't needed either, none of these grep
uses deal with binary data.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Stop including $(NO_CURL) in $(SCRIPT_DEFINES). The "@NO_CURL@"
replacement added in 6c5c62f340 (Print an error if cloning a http
repo and NO_CURL is set, 2006-02-15) has not been referenced by
anything in-tree since 49eb8d39c7 (Remove contrib/examples/*,
2018-03-25).
That commit removed the reference from contrib/examples/*, but this
@@NO_CURL@@ hasn't been used since git-pull.sh was the primary entry
point for "git pull".
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Remove the $(GIT_VERSION) from $(SCRIPT_DEFINES). Now every time HEAD
changes in a development copy we don't need to re-build the scripts
and script libraries.
This has not been needed since 2b9391bc67 (Makefile: do not replace
@@GIT_VERSION@@ in shell scripts, 2012-06-20). On my setup this
changes the re-making of 44 targets in a development copy where moved
HEAD to 27.
The $(GIT_VERSION) was seemingly left here by mistake or omission. We
didn't need it since 2b9391bc67, but in the later
e4dd89ab98 (Makefile: update scripts when build-time parameters
change, 2012-06-20) it was added to SCRIPT_DEFINES.
The two were part of the same series of patches, and given the summary
in [1] and [2] it looks like this was probably a case of some earlier
version of a later patch being combined with an updated earlier patch.
1. https://lore.kernel.org/git/20120619232231.GA6328@sigill.intra.peff.net/
2. https://lore.kernel.org/git/20120619232453.GB6496@sigill.intra.peff.net/
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When "GIT-SCRIPT-DEFINES" was added in e4dd89ab98 (Makefile: update
scripts when build-time parameters change, 2012-06-20) the rules for
generating the scripts themselves were moved further away from the
"cmd_munge_script" added in 46bac90458 (Do not install shell
libraries executable, 2010-01-31).
Let's move these around so that the variables and defines needed by
given targets immediately precede them. This is not needed for any
subsequent changes to work, but makes the code consistent with how
GIT-PERL-DEFINES is structured.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The "--preserve-merges" option of "git rebase" has been removed.
* js/retire-preserve-merges:
sequencer: restrict scope of a formerly public function
rebase: remove a no-longer-used function
rebase: stop mentioning the -p option in comments
rebase: remove obsolete code comment
rebase: drop the internal `rebase--interactive` command
git-svn: drop support for `--preserve-merges`
rebase: drop support for `--preserve-merges`
pull: remove support for `--rebase=preserve`
tests: stop testing `git rebase --preserve-merges`
remote: warn about unhandled branch.<name>.rebase values
t5520: do not use `pull.rebase=preserve`
Prevent "make sparse" from running for the source files that
haven't been modified.
* ab/make-sparse-for-real:
Makefile: make the "sparse" target non-.PHONY
Mostly preliminary clean-up in the hook API.
* ab/config-based-hooks-1:
hook-list.h: add a generated list of hooks, like config-list.h
hook.c users: use "hook_exists()" instead of "find_hook()"
hook.c: add a hook_exists() wrapper and use it in bugreport.c
hook.[ch]: move find_hook() from run-command.c to hook.c
Makefile: remove an out-of-date comment
Makefile: don't perform "mv $@+ $@" dance for $(GENERATED_H)
Makefile: stop hardcoding {command,config}-list.h
Makefile: mark "check" target as .PHONY
"make clean" has been updated to remove leftover .depend/
directories, even when it is not told to use them to compute header
dependencies.
* ab/make-clean-depend-dirs:
Makefile: clean .depend dirs under COMPUTE_HEADER_DEPENDENCIES != yes
CI learns to run the leak sanitizer builds.
* ab/sanitize-leak-ci:
tests: add a test mode for SANITIZE=leak, run it in CI
Makefile: add SANITIZE=leak flag to GIT-BUILD-OPTIONS
This command dumps individual tables or a stack of of tables.
Signed-off-by: Han-Wen Nienhuys <hanwen@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The packed/loose format has restrictions on refnames: a and a/b cannot
coexist. This limitation does not apply to reftable per se, but must be
maintained for interoperability. This code adds validation routines to
abort transactions that are trying to add invalid names.
Signed-off-by: Han-Wen Nienhuys <hanwen@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This adds an abstract, read-only interface to the ref database.
This primitive is used to construct the read view of the ref database
(the read view is constructed by merging several *.ref files). It also
provides the mechanism to provide a unified view of the refs in the main
repository and the per-worktree refs.
Signed-off-by: Han-Wen Nienhuys <hanwen@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This is needed to create a merged view multiple reftables
Signed-off-by: Han-Wen Nienhuys <hanwen@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
With support for reading and writing files in place, we can construct files (in
memory) and attempt to read them back.
Because some sections of the format are optional (eg. indices, log entries), we
have to exercise this code using multiple sizes of input data
Signed-off-by: Han-Wen Nienhuys <hanwen@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This supports reading a single reftable file.
The commit introduces an abstract iterator type, which captures the usecases
both of reading individual refs, and iterating over a segment of the ref
namespace.
Signed-off-by: Han-Wen Nienhuys <hanwen@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Junio C Hamano
Neeraj Singh
Ævar Arnfjörð Bjarmason
John Cai
brian m. carlson
Emily Shaffer
Johannes Schindelin
Han-Wen Nienhuys