Commit Graph

123 Commits (v2.50.0-rc0)

Author SHA1 Message Date
Patrick Steinhardt 88d4bff8c3 meson: wire up generation of distribution archive
Meson knows to generate distribution archives via `meson dist`. In
addition to generating the archive itself, this target also knows to
compile and execute tests from that archive, which helps to ensure that
the result is an adequate drop-in replacement for the versioned project.

While this already works as-is, one omission is that we don't propagate
the commit that this is built from into the resulting archive. This can
be fixed though by adding a distribution script that propagates the
version into the "version" file, which GIT-VERSION-GEN knows to read if
present.

Use GIT-VERSION-GEN to populate that file. As the script is executed in
the build directory, not in the directory where we generate the archive,
we have to use a shell to resolve the "MESON_DIST_ROOT" environment
variable.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-01-22 12:37:33 -08:00
Patrick Steinhardt 5d0cf6bb3a meson: wire up development environments
The Meson build system is able to wire up development environments. The
intent is to make build artifacts of the project available. This is
typically used to export e.g. paths to linkable libraries, which isn't
all that interesting in our context given that we don't have an official
library interface.

But what we can use this mechanism for is to expose the built Git
executables as well as the build directory. This allows users to play
around with the built Git version in the devenv, and allows them to
execute our test scripts directly with the built distribution.

Wire up this feature, which can then be used via `meson devenv` in the
build directory.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-01-22 12:37:33 -08:00
Patrick Steinhardt 53d75bd3e4 meson: fix dependencies for generated headers
We generate a couple of headers from our documentation. These headers
are added to the libgit sources, but two of them aren't used by the
library, but instead by our builtins. This can cause parallel builds to
fail because the builtin object may be compiled before the header was
generated.

Fix the issue by adding both "config-list.h" and "hook-list.h" to the
list of builtin sources. While "command-list.h" is generated similarly,
it is used by "help.c" and thus part of the libgit sources indeed.

Reported-by: Evan Martin <evan.martin@gmail.com>
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-01-22 12:37:33 -08:00
Patrick Steinhardt 6ff99174d1 meson: populate project version via GIT-VERSION-GEN
The Git version for Meson is currently wired up manually. It can thus
grow (and already has grown) stale quite easily, as having multiple
sources of truth is never a good idea. This issue is mostly of cosmetic
nature as we don't use the project version anywhere, and instead use the
GIT-VERSION-GEN script to propagate the correct version into our build.
But it is somewhat puzzling when `meson setup` announces to build an old
Git release.

There are a couple of alternatives for how to solve this:

  - We can keep the version undefined, but this makes Meson output
    "undefined" for the version, as well.

  - We can use GIT-VERSION-GEN to generate the version for us. At the
    point of configuring the project we haven't yet figured out host
    details though, and thus we didn't yet set up the shell environment.
    While not an issue for Unix-based systems, this would be an issue in
    Windows, where the shell typically gets provided via Git for Windows
    and thus requires some special setup.

  - We can pull the default version out of GIT-VERSION-GEN and move it
    into its own file. This likely requires some adjustments for scripts
    that bump the version, but allows Meson to read the version from
    that file trivially.

Pick the second option and use GIT-VERSION-GEN as it gives us the most
accurate version. In order to fix the bootstrapping issue on Windows
systems we simply set the version to 'unknown' in case no shell was
found. As the version is only of cosmetic value this isn't really much
of an issue.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-01-22 12:37:32 -08:00
Patrick Steinhardt c5bc9a7f94 Makefile: wire up build option for deprecated features
With 57ec9254eb (docs: introduce document to announce breaking changes,
2024-06-14), we have introduced a new document that tracks upcoming
breaking changes in the Git project. In 2454970930 (BreakingChanges:
early adopter option, 2024-10-11) we have amended the document a bit to
mention that any introduced breaking changes must be accompanied by
logic that allows us to enable the breaking change at compile-time.
While we already have two breaking changes lined up, neither of them has
such a switch because they predate those instructions.

Introduce the proposed `WITH_BREAKING_CHANGES` preprocessor macro and
wire it up with both our Makefiles and Meson. This does not yet wire up
the build flag for existing deprecations.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-01-22 12:28:27 -08:00
Patrick Steinhardt eb8728d88a meson: stop disabling -Wsign-compare
In 4f9264b0cd (config.mak.dev: drop `-Wno-sign-compare`, 2024-12-06) we
have started an effort to make our codebase compile with -Wsign-compare.
But while we removed the -Wno-sign-compare flag from "config.mak.dev",
we didn't adjust the Meson build instructions in the same way.

Fix this.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-01-21 14:20:28 -08:00
brian m. carlson 1f010d6bdf doc: use .adoc extension for AsciiDoc files
We presently use the ".txt" extension for our AsciiDoc files.  While not
wrong, most editors do not associate this extension with AsciiDoc,
meaning that contributors don't get automatic editor functionality that
could be useful, such as syntax highlighting and prose linting.

It is much more common to use the ".adoc" extension for AsciiDoc files,
since this helps editors automatically detect files and also allows
various forges to provide rich (HTML-like) rendering.  Let's do that
here, renaming all of the files and updating the includes where
relevant.  Adjust the various build scripts and makefiles to use the new
extension as well.

Note that this should not result in any user-visible changes to the
documentation.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-01-21 12:56:06 -08:00
Patrick Steinhardt 8454b42f94 meson: wire up the git-subtree(1) command
Wire up the git-subtree(1) command, which is part of "contrib/". Note
that we have to move around the exact location where we include the
"contrib/" subdirectory so that it comes after building the docs so that
we have access to some of the common functionality.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-01-17 09:56:38 -08:00
Toon Claes 4771501c0a meson: ensure correct version-def.h is used
To build the libgit-version library, Meson first generates
`version-def.h` in the build directory. Then it compiles `version.c`
into a library. During compilation, Meson tells to include both the
build directory and the project root directory.

However, when the user previously has compiled Git using Make, they will
have a `version-def.h` file in project root directory as well. Because
`version-def.h` is included in `version.c` using the #include directive
with double quotes, some preprocessors will look for the header file in
the same directory as the source file. This will cause compilation of
`version.c` ran by Meson to include `version-def.h` previously made by
Make, which might be out of date.

To explicitly tell the preprocessor which `version-def.h` to use, pass
the absolute path of this file as macro GIT_VERSION_H to the
preprocessor using option `-D` and have `version.c` `#include
GIT_VERSION_H`. To remain working with other build systems than Meson,
include "version-def.h" if that macro is not defined.

Co-authored-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Toon Claes <toon@iotcl.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-01-14 11:14:54 -08:00
Patrick Steinhardt 6a0ee54f9a meson: provide a summary of configured backends
There are a couple of backends from which the user can choose for HTTPS,
SHA1, its unsafe variant as well as SHA256. Provide a summary of the
configured values to make these more discoverable.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-12-30 06:50:49 -08:00
Patrick Steinhardt d2c0b6a86c meson: wire up unsafe SHA1 backend
In 06c92dafb8 (Makefile: allow specifying a SHA-1 for non-cryptographic
uses, 2024-09-26), we have introduced a cryptographically-insecure
backend for SHA1 that can optionally be used in some contexts where the
processed data is not security relevant. This effort was in-flight with
the effort to introduce Meson, so we don't have an equivalent here.

Wire up a new build option that lets users pick an unsafe SHA1 backend.

Note that for simplicity's sake we have to drop the error condition
around an unhandled SHA1 backend. This should be fine though given that
Meson verifies the value for combo-options for us.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-12-30 06:50:49 -08:00
Patrick Steinhardt 6d8aa2aec8 meson: simplify conditions for HTTPS and SHA1 dependencies
The conditions used to figure out whteher the Security framework or
OpenSSL library is required are a bit convoluted because they can be
pulled in via the HTTPS, SHA1 or SHA256 backends. Refactor them to be
easier to read.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-12-30 06:50:46 -08:00
Patrick Steinhardt d6787d9751 meson: require SecurityFramework when it's used as SHA1 backend
The Security framework is required when we use CommonCrypto either as
HTTPS or SHA1 backend, but we only require it in case it is set up as
HTTPS backend. Fix this.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-12-30 06:50:45 -08:00
Patrick Steinhardt 31eb6d7cf0 meson: deduplicate access to SHA1/SHA256 backend options
We've got a couple of repeated calls to `get_option()` for the SHA1 and
SHA256 backend options. While not an issue, it makes the code needlessly
verbose.

Fix this by consistently using a local variable.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-12-30 06:50:45 -08:00
Patrick Steinhardt 8214e27d27 meson: consistenlty spell 'CommonCrypto'
The 'CommonCrypto' backend can be specified as HTTPS and SHA1 backends,
but the value that one needs to use is inconsistent across those two
build options. Unify it to 'CommonCrypto'.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-12-30 06:50:45 -08:00
Patrick Steinhardt d963ac98ec meson: enable auto-discovered "gitweb"
In 7d549fe317 (meson: skip gitweb build when Perl is disabled,
2024-12-20) we have started to conditionally enable "gitweb" based on
whether or not Perl is enabled. By accident though that change causes us
to not build gitweb in case its feature flag is set to "auto" even if
autoconfiguration determines that it could be built. This is because we
use "gitweb_option.enabled()", which only checks whether the feature has
been explicitly enabled.

Fix the issue by using `gitweb_option.allowed()` instead, which returns
true in case it is either explicitly enabled or set to "auto". This also
works for the case where the feature becomes auto-disabled due to Perl
not being present because we use `disable_auto_if(not perl.found())`.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-12-27 08:17:19 -08:00
Patrick Steinhardt cbcc2f7911 GIT-BUILD-OPTIONS: wire up NO_GITWEB option
Building our "gitweb" interface is optional in our Makefile and in Meson
and not wired up at all with CMake, but disabling it causes a couple of
tests in the t950* range that pull in "t/lib-gitweb.sh". This is because
the test library knows to execute gitweb-tests based on whether or not
Perl is available, but we may have Perl available and still end up not
building gitweb e.g. with `make test NO_GITWEB=YesPlease`.

Fix this issue by wiring up a new "NO_GITWEB" build option so that we
can skip these tests in case gitweb is not built.

Note that this new build option requires us to move the configuration of
GIT-BUILD-OPTIONS to a later point in our Meson build instructions. But
as that file is only consumed by our tests at runtime this change does
not cause any issues.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-12-27 08:17:19 -08:00
Junio C Hamano f074cdea46 Merge branch 'ps/build-hotfix'
A topic to optionally build with meson, which has graduated to
'master' recently, has regressed the normal Makefile build, which
is being corrected.

* ps/build-hotfix:
  meson: add options to override build information
  GIT-VERSION-GEN: fix overriding GIT_BUILT_FROM_COMMIT and GIT_DATE
  GIT-VERSION-GEN: fix overriding GIT_VERSION
  Makefile: introduce template for GIT-VERSION-GEN
  Makefile: drop unneeded indirection for GIT-VERSION-GEN outputs
  Makefile: stop including "GIT-VERSION-FILE" in docs
2024-12-23 09:32:26 -08:00
Junio C Hamano 83c8f76235 Merge branch 'ps/ci-meson'
The meson-build procedure is integrated into CI to catch and
prevent bitrotting.

* ps/ci-meson:
  ci: wire up Meson builds
  t: introduce compatibility options to clar-based tests
  t: fix out-of-tree tests for some git-p4 tests
  Makefile: detect missing Meson tests
  meson: detect missing tests at configure time
  t/unit-tests: rename clar-based unit tests to have a common prefix
  Makefile: drop -DSUPPRESS_ANNOTATED_LEAKS
  ci/lib: support custom output directories when creating test artifacts
2024-12-23 09:32:25 -08:00
Patrick Steinhardt 1bc815c3d0 meson: add options to override build information
We inject various different kinds of build information into build
artifacts, like the version string or the commit from which Git was
built. Add options to let users explicitly override this information
with Meson.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-12-20 12:36:46 -08:00
Patrick Steinhardt 7d549fe317 meson: skip gitweb build when Perl is disabled
It is possible to configure a Git build without Perl when disabling both
our test suite and all Perl-based features. In Meson, this can be
achieved with `meson setup -Dperl=disabled -Dtests=false`.

It was reported by a user that this breaks the Meson build because
gitweb gets built even if Perl was not discovered in such a build:

    $ meson setup .. -Dtests=false -Dperl=disabled
    ...
    ../gitweb/meson.build:2:43: ERROR: Unable to get the path of a not-found external program

Fix this issue by introducing a new feature-option that allows the user
to configure whether or not to build Gitweb. The feature is set to
'auto' by default and will be disabled automatically in case Perl was
not found on the system.

Reported-by: Daniel Engberg <daniel.engberg.lists@pyret.net>
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-12-20 08:39:20 -08:00
Patrick Steinhardt 23eeee08d6 Makefile: drop -DSUPPRESS_ANNOTATED_LEAKS
The -DSUPPRESS_ANNOTATED_LEAKS preprocessor directive was used to enable
our `UNLEAK()` macro in the past, which marks memory as still-reachable
so that the leak sanitizer does not complain. Starting with 52c7dbd036
(git-compat-util: drop now-unused `UNLEAK()` macro, 2024-11-20) this
macro has been removed, and thus the preprocessor directive is not
required anymore, either.

Drop it.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-12-13 06:48:45 -08:00
Patrick Steinhardt 904339edbd Introduce support for the Meson build system
Introduce support for the Meson build system, a "modern" meta build
system that supports many different platforms, including Linux, macOS,
Windows and BSDs. Meson supports different backends, including Ninja,
Xcode and Microsoft Visual Studio. Several common IDEs provide an
integration with it.

The biggest contender compared to Meson is probably CMake as outlined in
our "Documentation/technical/build-systems.txt" file. Based on my own
personal experience from working with both build systems extensively I
strongly favor Meson over CMake. In my opinion, it feels significantly
easier to use with a syntax that feels more like a "real" programming
language. The second big reason is that Meson supports Rust natively,
which may prove to be important given that the project may pick up Rust
as another language eventually.

Using Meson is rather straight-forward. An example:

    ```
    # Meson uses out-of-tree builds. You can set up multiple build
    # directories, how you name them is completely up to you.
    $ mkdir build
    $ cd build
    $ meson setup .. -Dprefix=/tmp/git-installation

    # Build the project. This also provides several other targets like
    e.g. `install` or `test`.
    $ ninja

    # Meson has been wired up to support execution of our test suites.
    # Both our unit tests and our integration tests are supported.
    # Running `meson test` without any arguments will execute all tests,
    # but the syntax supports globbing to select only some tests.
    $ meson test 't-*'
    # Execute single test interactively to allow for debugging.
    $ meson test 't0000-*' --interactive --test-args=-ix
    ```

The build instructions have been successfully tested on the following
systems, tests are passing:

  - Apple macOS 10.15.

  - FreeBSD 14.1.

  - NixOS 24.11.

  - OpenBSD 7.6.

  - Ubuntu 24.04.

  - Windows 10 with Cygwin.

  - Windows 10 with MinGW64, except for t9700, which is also broken with
    our Makefile.

  - Windows 10 with Visual Studio 2022 toolchain, using the Native Tools
    Command Prompt with `meson setup --vsenv`. Tests pass, except for
    t9700.

  - Windows 10 with Visual Studio 2022 solution, using the Native Tools
    Command Prompt with `meson setup --backend vs2022`. Tests pass,
    except for t9700.

  - Windows 10 with VS Code, using the Meson plug-in.

It is expected that there will still be rough edges in the current
version. If this patch lands the expectation is that it will coexist
with our other build systems for a while. Like this, distributions can
slowly migrate over to Meson and report any findings they have to us
such that we can continue to iterate. A potential cutoff date for other
build systems may be Git 3.0.

Some notes:

  - The installed distribution is structured somewhat differently than
    how it used to be the case. All of our binaries are installed into
    `$libexec/git-core`, while all binaries part of `$bindir` are now
    symbolic links pointing to the former. This rule is consistent in
    itself and thus easier to reason about.

  - We do not install dashed binaries into `$libexec/git-core` anymore,
    so there won't e.g. be a symlink for git-add(1). These are not
    required by modern Git and there isn't really much of a use case for
    those anymore. By not installing those symlinks we thus start the
    deprecation of this layout.

  - We're targeting Meson 1.3.0, which has been released relatively
    recently November 2023. The only feature we use from that version is
    `fs.relative_to()`, which we could replace if necessary. If so, we
    could start to target Meson 1.0.0 and newer, released in December
    2022.

  - The whole build instructions count around 3300 lines, half of which
    is listing all of our code and test files. Our Makefiles are around
    5000 lines, autoconf adds another 1300 lines. CMake in comparison
    has only 1200 linescode, but it avoids listing individual files and
    does not wire up auto-configuration as extensively as the Meson
    instructions do.

  - We bundle a set of subproject wrappers for curl, expat, openssl,
    pcre2 and zlib. This allows developers to build Git without these
    dependencies preinstalled, and Meson will fetch and build them
    automatically. This is especially helpful on Windows.

Helped-by: Eli Schwartz <eschwartz@gentoo.org>
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-12-07 07:52:14 +09:00