Add release.sh

Replace xorg-util-modular's release script with our own, tailored
for Wayland only. Does the same thing but in 71 lines of code
instead of 1k. Creates a GitLab release via glab instead of trying
to upload to a web server via ssh.

Signed-off-by: Simon Ser <contact@emersion.fr>

release.sh

@@ -0,0 +1,70 @@
+#!/bin/sh -eu
+
+build_dir=build-release
+
+if ! type glab >/dev/null; then
+	echo "glab is needed to create a release"
+	exit 1
+fi
+
+case "$(git rev-parse --abbrev-ref HEAD)" in
+main | [0-9]*.[0-9]*)
+	;;
+*)
+	echo "Not on the main or a stable branch"
+	exit 1
+esac
+
+if [ -n "$(git log @{upstream}..)" ]; then
+	echo "The main branch has unpushed commits"
+	exit 1
+fi
+
+meson_options=""
+if [ -e "$build_dir" ]; then
+	meson_options="$meson_options --wipe"
+fi
+meson setup "$build_dir" $meson_options
+
+prev_version="$(git describe --tags --abbrev=0)"
+version="$(meson introspect "$build_dir" --projectinfo | jq -r .version)"
+if [ "$version" = "$prev_version" ]; then
+	echo "Version not bumped"
+	exit 1
+fi
+
+ninja -C "$build_dir" dist
+
+archive_name="wayland-$version.tar.xz"
+archive_path="$build_dir/meson-dist/$archive_name"
+gpg --detach-sig "$archive_path"
+
+sha256="$(cd $build_dir/meson-dist && sha256sum $archive_name)"
+sha512="$(cd $build_dir/meson-dist && sha512sum $archive_name)"
+archive_url="https://gitlab.freedesktop.org/wayland/wayland/-/releases/$version/downloads/$archive_name"
+announce_path="$build_dir/meson-dist/wayland-$version-announce.eml"
+cat >"$announce_path" <<EOF
+To: <wayland-devel@lists.freedesktop.org>
+Subject: [ANNOUNCE] wayland $version
+
+`git shortlog --no-merges "$prev_version.."`
+
+git tag: $version
+
+$archive_url
+SHA256: $sha256
+SHA512: $sha512
+PGP:    $archive_url.sig
+EOF
+
+echo "Release announcement written to $announce_path"
+
+echo -n "Release wayland $version? [y/N] "
+read answer
+if [ "$answer" != "y" ]; then
+	exit 1
+fi
+
+git tag -s -m "$version" "$version"
+git push --tags
+glab release create "$version" "$archive_path"* --notes ""