Import jack2-1.9.21-r1.ebuild from main gentoo portage tree

jack2 and jackdbus codebases were separated recently.
As part of LADIOS project at least, media-sound/jack2 will continue
to provide libjack and libjackserver, but neither
jackdbus nor jackd will be installable through the ebuild.

jackdbus will be installable via new media-sound/jackdbus ebuild.

jackd was deprecated in LADI project more than a decade ago
and soon will not be installable anymore (unless someone
creates in a different overlay a jackd ebuild that uses the
media-sound/jack2[-classic,-dbus] and handles the support
in a different project)

dbus device reservation code in jack2 libjackserver will be
enabled no matter what [classic/dbus] use flags are supplied.

The dbus use flag used to enable jackdbus for jack2.
Since then, jackd got dbus reservation support.
A dedicated jackd ebuild that uses media-sound/jack2[-classic,-dbus]
could provide installable jackd with with dbus device reservation support.

media-sound/jack2/jack2-1.9.21-r1.ebuild

@@ -0,0 +1,113 @@
+# Copyright 1999-2023 Gentoo Authors
+# Distributed under the terms of the GNU General Public License v2
+
+EAPI=8
+
+PYTHON_COMPAT=( python3_{9..11} )
+PYTHON_REQ_USE="threads(+)"
+inherit flag-o-matic python-single-r1 waf-utils multilib-minimal
+
+if [[ ${PV} == 9999 ]]; then
+	inherit git-r3
+	EGIT_REPO_URI="https://github.com/jackaudio/${PN}.git"
+else
+	SRC_URI="https://github.com/jackaudio/jack2/archive/refs/tags/v${PV}.tar.gz -> ${P}.tar.gz"
+	KEYWORDS="amd64 arm arm64 ~loong ppc ppc64 ~riscv x86"
+fi
+
+DESCRIPTION="Jackdmp jack implemention for multi-processor machine"
+HOMEPAGE="https://jackaudio.org/"
+
+LICENSE="GPL-2+ LGPL-2.1+"
+SLOT="2"
+IUSE="+alsa +classic dbus doc ieee1394 libsamplerate metadata opus pam +tools systemd"
+REQUIRED_USE="
+	${PYTHON_REQUIRED_USE}
+	|| ( classic dbus )"
+
+DEPEND="
+	alsa? ( media-libs/alsa-lib[${MULTILIB_USEDEP}] )
+	dbus? (
+		dev-libs/expat[${MULTILIB_USEDEP}]
+		sys-apps/dbus[${MULTILIB_USEDEP}]
+	)
+	libsamplerate? ( media-libs/libsamplerate[${MULTILIB_USEDEP}] )
+	ieee1394? ( media-libs/libffado[${MULTILIB_USEDEP}] )
+	metadata? ( sys-libs/db:=[${MULTILIB_USEDEP}] )
+	opus? ( media-libs/opus[custom-modes,${MULTILIB_USEDEP}] )
+	systemd? ( classic? ( sys-apps/systemd:= ) )"
+RDEPEND="
+	${DEPEND}
+	dbus? (
+		${PYTHON_DEPS}
+		$(python_gen_cond_dep '
+			dev-python/dbus-python[${PYTHON_USEDEP}]
+		')
+	)
+	pam? ( sys-auth/realtime-base )
+	!media-sound/jack-audio-connection-kit
+	!media-video/pipewire[jack-sdk(-)]"
+BDEPEND="
+	${PYTHON_DEPS}
+	virtual/pkgconfig
+	doc? ( app-doc/doxygen )"
+# tools were formerly provided here, pull to maintain expectations
+PDEPEND="tools? ( media-sound/jack-example-tools )"
+
+DOCS=( AUTHORS.rst ChangeLog.rst README.rst README_NETJACK2 )
+
+PATCHES=(
+	"${FILESDIR}"/${PN}-1.9.21-python3.11.patch
+)
+
+src_prepare() {
+	default
+
+	python_fix_shebang waf
+	multilib_copy_sources
+}
+
+multilib_src_configure() {
+	# clients crash if built with lto
+	# https://github.com/jackaudio/jack2/issues/485
+	filter-lto
+
+	local wafargs=(
+		--mandir="${EPREFIX}"/usr/share/man/man1 # override eclass' for man1
+
+		--alsa=$(usex alsa)
+		--celt=no
+		$(usev classic --classic)
+		--db=$(usex metadata)
+		$(usev dbus --dbus)
+		--doxygen=$(multilib_native_usex doc)
+		--firewire=$(usex ieee1394)
+		--iio=no
+		--opus=$(usex opus)
+		--portaudio=no
+		--samplerate=$(usex libsamplerate)
+		--systemd=$(multilib_native_usex systemd $(usex classic))
+		--winmme=no
+
+		# obsolete options, migrated to media-sound/jack-example-tools
+		# and will be removed entirely next version
+		--example-tools=no
+		--readline=no
+		--sndfile=no
+		--zalsa=no
+	)
+
+	waf-utils_src_configure "${wafargs[@]}"
+}
+
+multilib_src_compile() {
+	waf-utils_src_compile
+}
+
+multilib_src_install() {
+	waf-utils_src_install
+}
+
+multilib_src_install_all() {
+	use dbus && python_fix_shebang "${ED}"/usr/bin/jack_control
+}