[igt-dev] [PATCH 1/1] meson: Set up runpath for installed executables

[Arkadiusz Hiler]

On Fri, Jan 19, 2018 at 01:44:07PM +0200, Latvala, Petri wrote:
> Meson builds libigt as a shared library, and executables naturally
> have to find it at runtime. Using default options puts the library to
> a normal search paths, but any modifications to the directory options
> or a non-conventional prefix setting makes using LD_LIBRARY_PATH or
> other library search means mandatory.
> 
> Add a build option 'use_rpath' (default: false) that makes meson set
> up DT_RUNPATH at install time, pointing to the library with a path
> relative to the executable, using $ORIGIN. That way the installed
> executables find the library even when not installed to exactly the
> build-time configured prefix path, a setup CI occasionally uses.
> 
> Signed-off-by: Petri Latvala <petri.latvala at intel.com>
> Cc: Tomi Sarvela <tomi.p.sarvela at intel.com>
> Cc: Arkadiusz Hiler <arkadiusz.hiler at intel.com>
> ---
>  meson_options.txt |  4 ++++
>  tests/meson.build | 26 ++++++++++++++++++++++++++
>  tools/meson.build | 26 ++++++++++++++++++++++++++
>  3 files changed, 56 insertions(+)
>  create mode 100644 meson_options.txt
> 
> diff --git a/meson_options.txt b/meson_options.txt
> new file mode 100644
> index 00000000..41be35e0
> --- /dev/null
> +++ b/meson_options.txt
> @@ -0,0 +1,4 @@
> +option('use_rpath',
> +       type : 'boolean',
> +       value : false,
> +       description : 'Set runpath on installed executables for libigt.so')
> diff --git a/tests/meson.build b/tests/meson.build
> index 2322217d..b764b7f7 100644
> --- a/tests/meson.build
> +++ b/tests/meson.build
> @@ -255,24 +255,49 @@ if alsa.found() and gsl.found()
>  	test_deps += alsa
>  endif
>  
> +if get_option('use_rpath')
> +	# Set up runpath for the test executables towards libigt.so.
> +	# The path should be relative to $ORIGIN so the library is
> +	# still found properly even if installed to a path other than
> +	# prefix.
> +
> +	# libdir and libexecdir are pathnames relative to
> +	# prefix. meson enforces this.
> +
> +	# Start from the executable
> +	rpathdir = '$ORIGIN'
> +	# Executables are installed in libexecdir. Add a .. for each
> +	# directory name in it.
> +	foreach p : libexecdir.split('/')
> +		rpathdir = join_paths(rpathdir, '..')
> +	endforeach
> +	# Add relative path to libdir
> +	rpathdir = join_paths(rpathdir, libdir)

Theoretically there is $LIB which:
"They will be replaced by [...] or either lib - for 32-bit binaries - or
lib64 - for 64-bit binaries - in the case of $LIB"

But I think I like current soultion more.

Reviewed-by: Arkadiusz Hiler <arkadiusz.hiler at intel.com>
Tested-by: Arkadiusz Hiler <arkadiusz.hiler at intel.com>

I'll push it in a minute.

I've learend something today, thanks!

-- 
Cheers,
Arek