[libcamera-devel] [RFC 1/1] build: Preserve upstream git versioning using meson dist

[Naushir Patuck]

On Wed, 13 Oct 2021 at 11:19, Naushir Patuck <naush at raspberrypi.com> wrote:

> When distributions build and package libcamera libraries, they may not
> necessarily run the build in the upstream source tree. In these cases, the
> git
> SHA1 versioning information will be lost.
>
> This change addresses that problem by requiring package managers to run
> 'meson dist' to create a tarball of the source files and build from there.
> On runing 'meson dist', the utils/run-dist.sh script will create a
> version.gen
> file in the release tarball with the version string generated from the
> existing
> utils/gen-version.sh script.
>
> The build system has been updated to check for the presence of this
> version.gen
> file and read the version string from it. If the file is not present, the
> version string is generated by running utils/gen-version.sh as it currently
> does.
>
> Signed-off-by: Naushir Patuck <naush at raspberrypi.com>
> ---
>  meson.build               | 30 ++++++++++++++++++++----------
>  src/libcamera/meson.build | 11 +++++------
>  utils/run-dist.sh         |  9 +++++++++
>  3 files changed, 34 insertions(+), 16 deletions(-)
>  create mode 100644 utils/run-dist.sh
>
> diff --git a/meson.build b/meson.build
> index a49c484fe64e..f27bfd479a5c 100644
> --- a/meson.build
> +++ b/meson.build
> @@ -10,20 +10,30 @@ project('libcamera', 'c', 'cpp',
>      ],
>      license : 'LGPL 2.1+')
>
> -# Generate version information. The libcamera_git_version variable
> contains the
> -# full version with git patch count and SHA1 (e.g. 1.2.3+211-c94a24f4),
> while
> -# the libcamera_version variable contains the major.minor.patch (e.g.
> 1.2.3)
> -# only. If the source tree isn't under git control, or if it matches the
> last
> -# git version tag, the build metadata (e.g. +211-c94a24f4) is omitted from
> -# libcamera_git_version.
> -libcamera_git_version = run_command('utils/gen-version.sh',
> -                                    meson.build_root()).stdout().strip()
> -if libcamera_git_version == ''
> -    libcamera_git_version = meson.project_version()
> +fs_mod = import('fs')
> +if not fs_mod.is_file('version.gen')
> +    # Generate version information. The libcamera_git_version variable
> contains the
> +    # the full version with git patch count and SHA1 (e.g.
> 1.2.3+211-c94a24f4), while
> +    # the libcamera_version variable contains the major.minor.patch (e.g.
> 1.2.3)
> +    # only. If the source tree isn't under git control, or if it matches
> the last
> +    # git version tag, the build metadata (e.g. +211-c94a24f4) is omitted
> from
> +    # libcamera_git_version.
> +    libcamera_git_version = run_command('utils/gen-version.sh',
> +
> meson.build_root()).stdout().strip()
> +    if libcamera_git_version == ''
> +        libcamera_git_version = meson.project_version()
> +    endif
> +else
> +    # Read the version information from the file generated by the
> utils/run-dist.sh
> +    # script on a 'meson dist' command.
> +    libcamera_git_version = run_command(['cat',
> 'version.gen']).stdout().strip()
>  endif
>

I've added an if clause here to check for the presence of the version file,
but I
could equally leave this as-is and check for the file in gen-version.sh.  I
don't have
a strong preference either way.

Naush


>
>  libcamera_version = libcamera_git_version.split('+')[0]
>
> +# This script gererates the version.gen file on a 'meson dist' command.
> +meson.add_dist_script('utils/run-dist.sh')
> +
>  # Configure the build environment.
>  cc = meson.get_compiler('c')
>  cxx = meson.get_compiler('cpp')
> diff --git a/src/libcamera/meson.build b/src/libcamera/meson.build
> index 243dd3c180eb..360eaf80ecf1 100644
> --- a/src/libcamera/meson.build
> +++ b/src/libcamera/meson.build
> @@ -93,12 +93,11 @@ endforeach
>
>  libcamera_sources += control_sources
>
> -gen_version = meson.source_root() / 'utils' / 'gen-version.sh'
> -
> -version_cpp = vcs_tag(command : [gen_version, meson.build_root()],
> -                      input : 'version.cpp.in',
> -                      output : 'version.cpp',
> -                      fallback : meson.project_version())
> +version_data = configuration_data()
> +version_data.set('VCS_TAG', libcamera_git_version)
> +version_cpp = configure_file(input : 'version.cpp.in',
> +                             output : 'version.cpp',
> +                             configuration : version_data)
>
>  libcamera_sources += version_cpp
>
> diff --git a/utils/run-dist.sh b/utils/run-dist.sh
> new file mode 100644
> index 000000000000..1b2a6348c6bc
> --- /dev/null
> +++ b/utils/run-dist.sh
> @@ -0,0 +1,9 @@
> +#!/bin/sh
> +
> +# SPDX-License-Identifier: GPL-2.0-or-later
> +#
> +# On a meson dist run, generate the version string and store it in a file.
> +# This will late be picked up by the build system and used in place of
> running
> +# the utils/gen-version.sh script again since we may not be running in the
> +# upstream git source tree, and so version information would be lost.
> +"$MESON_DIST_ROOT"/utils/gen-version.sh > "$MESON_DIST_ROOT"/version.gen
> --
> 2.25.1
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.libcamera.org/pipermail/libcamera-devel/attachments/20211013/dcea60a6/attachment.htm>