[libcamera-devel] [PATCH v4 1/2] utils: gen-version: Pass the meson source root to the gen-version.sh script

[Laurent Pinchart]

Hi Naush,

On Fri, Oct 15, 2021 at 08:39:58AM +0100, Naushir Patuck wrote:
> On Thu, 14 Oct 2021 at 21:37, Laurent Pinchart wrote:
> > On Thu, Oct 14, 2021 at 12:59:50PM +0100, Naushir Patuck wrote:
> > > The gen-version.sh script expects to be called from a git repo, and sets its
> > > src_root variable accordingly. This may not always be the case if it is built
> > > from a tarball source - full support for which is in a future commit.
> > >
> > > The MESON_SOURCE_ROOT environnement variable does not get set when called from
> > > the meson vcs_tag() function, but does when called from the run_command()
> > > function, so that cannot be used either.
> > >
> > > Instead, explicitly pass the meson source root to the gen-version.sh script.
> > >
> > > Signed-off-by: Naushir Patuck <naush at raspberrypi.com>
> > > ---
> > >  meson.build               | 3 ++-
> > >  src/libcamera/meson.build | 2 +-
> > >  utils/gen-version.sh      | 4 ++--
> > >  3 files changed, 5 insertions(+), 4 deletions(-)
> > >
> > > diff --git a/meson.build b/meson.build
> > > index a49c484fe64e..556a3f7c42f8 100644
> > > --- a/meson.build
> > > +++ b/meson.build
> > > @@ -17,7 +17,8 @@ project('libcamera', 'c', 'cpp',
> > >  # 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()
> > > +                                    meson.build_root(),
> > > + meson.source_root()).stdout().strip()
> > >  if libcamera_git_version == ''
> > >      libcamera_git_version = meson.project_version()
> > >  endif
> > > diff --git a/src/libcamera/meson.build b/src/libcamera/meson.build
> > > index 243dd3c180eb..d8dd8344002c 100644
> > > --- a/src/libcamera/meson.build
> > > +++ b/src/libcamera/meson.build
> > > @@ -95,7 +95,7 @@ libcamera_sources += control_sources
> > >
> > >  gen_version = meson.source_root() / 'utils' / 'gen-version.sh'
> >
> > While at it, could you please add
> >
> > # Use vcs_tag() and not configure_file() or run_command(), to ensure that the
> > # version gets updated with every ninja build and not just at meson setup time.
> >
> > so we'll remember next time ?
> 
> Will do!
> 
> > > -version_cpp = vcs_tag(command : [gen_version, meson.build_root()],
> > > +version_cpp = vcs_tag(command : [gen_version, meson.build_root(), meson.source_root()],
> > >                        input : 'version.cpp.in',
> > >                        output : 'version.cpp',
> > >                        fallback : meson.project_version())
> > > diff --git a/utils/gen-version.sh b/utils/gen-version.sh
> > > index b09ad495f86a..da191691a7c5 100755
> > > --- a/utils/gen-version.sh
> > > +++ b/utils/gen-version.sh
> > > @@ -4,10 +4,10 @@
> > >  # Generate a version string using git describe
> > >
> > >  build_dir="$1"
> > > +src_dir="$2"
> > >
> > >  # Bail out if the directory isn't under git control
> > > -src_dir=$(git rev-parse --git-dir 2>&1) || exit 1
> > > -src_dir=$(readlink -f "$src_dir/..")
> > > +git rev-parse --git-dir > /dev/null 2>&1 || exit 1
> >
> > It would be nice if we could make the source directory optional, the
> > same way the build directory is, so that running gen-version.sh from the
> > command line for testing would be easier. How about the following ?
> >
> > # Bail out if the directory isn't under git control
> > git_dir=$(git rev-parse --git-dir 2>&1) || exit 1
> >
> > # Derive the source directory from the git directory if not specified.
> > if [ -z "$src_dir" ]
> > then
> >         src_dir=$(readlink -f "$git_dir/..")
> > fi
> >
> >
> > With this (and assuming it works :-)),
> 
> Kieran had a suggestion in his feedback on a previous version of the patch.
> $build_dir/source symlinks to our source tree.  This is created from the top
> level meson.build file:
> 
> # Create a symlink from the build root to the source root. This is used when
> # running libcamera from the build directory to locate resources in the source
> # directory (such as IPA configuration files).
> run_command('ln', '-fsT', meson.source_root(), meson.build_root() / 'source')
> 
> Assuming this does not disappear in the future, I can use that to reference the
> source dir in the gen-version script. This will effectively make this patch (1/2)
> redundant, and I only need to change gen-version.sh appropriately.  What
> do you think?

That would only work when running the script from the build directory.
For testing purpose, it's nice to be able to run it manually in the
source directory, and get the same output as when run by meson. I'd thus
prefer deriving src_dir from git_dir when not specified.

> > Reviewed-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
> >
> > >  # Get a short description from the tree.
> > >  version=$(git describe --abbrev=8 --match "v[0-9]*" 2>/dev/null)

-- 
Regards,

Laurent Pinchart