x11-libs/gtk+: add a "poison" macro support to disable X/wayland

Many packages perform automagic dependencies on gdk's backend
implementations by checking if the macro is defined and then using the
code it unlocks, rather than having a buildsystem option such as
-Dwayland=true.

It's unfeasible to patch every such package's source code to add
configure options and respect them. Instead add a truly filthy hack and
permit gtk itself to selectively show or hide the windowing system in
use.

Bug: https://bugs.gentoo.org/624960
Signed-off-by: Eli Schwartz <eschwartz93@gmail.com>
Part-of: https://github.com/gentoo/gentoo/pull/37259
Signed-off-by: Eli Schwartz <eschwartz@gentoo.org>

3 files changed, 300 insertions, 0 deletions

diff --git a/x11-libs/gtk+/files/0001-gdk-add-a-poison-macro-to-hide-GDK_WINDOWING_.patch b/x11-libs/gtk+/files/0001-gdk-add-a-poison-macro-to-hide-GDK_WINDOWING_.patch
new file mode 100644
index 000000000000..26c56b86fe89
--- /dev/null
+++ b/x11-libs/gtk+/files/0001-gdk-add-a-poison-macro-to-hide-GDK_WINDOWING_.patch
@@ -0,0 +1,90 @@
+From 25bdad805bb9e16032baf4480e9c1e432ddef49b Mon Sep 17 00:00:00 2001
+From: Eli Schwartz <eschwartz93@gmail.com>
+Date: Wed, 19 Jun 2024 21:28:31 -0400
+Subject: [PATCH] gdk: add a "poison" macro to hide GDK_WINDOWING_*
+
+Many packages perform automagic dependencies on gdk's backend
+implementations by checking if the macro is defined and then using the
+code it unlocks, rather than having a buildsystem option such as
+-Dwayland=true.
+
+It's unfeasible to patch every such package's source code to add
+configure options and respect them. Instead add a truly filthy hack and
+permit gtk itself to selectively show or hide the windowing system in
+use.
+
+By default, we assume this macro is never defined. It should only ever
+be defined inside an ebuild, as such:
+
+```
+use wayland || append-cflags -DGENTOO_GTK_HIDE_WAYLAND
+use X || append-cflags -DGENTOO_GTK_HIDE_X11
+```
+
+When seen, this will prevent code using "#ifdef GDK_WINDOWING_*" from
+seeing the define, so the automagic dependency won't be picked up. It
+will also cause any attempt to #include the backend-specific headers to
+bug out.
+
+Bug: https://bugs.gentoo.org/624960
+Signed-off-by: Eli Schwartz <eschwartz93@gmail.com>
+---
+ gdk/gdkconfig.h.meson    | 7 +++++++
+ gdk/wayland/gdkwayland.h | 4 ++++
+ gdk/x11/gdkx.h           | 4 ++++
+ 3 files changed, 15 insertions(+)
+
+diff --git a/gdk/gdkconfig.h.meson b/gdk/gdkconfig.h.meson
+index 7db19e0470..6bee207e94 100644
+--- a/gdk/gdkconfig.h.meson
++++ b/gdk/gdkconfig.h.meson
+@@ -10,9 +10,16 @@
+ G_BEGIN_DECLS
+ 
+ 
++#ifndef GENTOO_GTK_HIDE_X11
+ #mesondefine GDK_WINDOWING_X11
++#endif
++
+ #mesondefine GDK_WINDOWING_BROADWAY
++
++#ifndef GENTOO_GTK_HIDE_WAYLAND
+ #mesondefine GDK_WINDOWING_WAYLAND
++#endif
++
+ #mesondefine GDK_WINDOWING_WIN32
+ #mesondefine GDK_WINDOWING_QUARTZ
+ 
+diff --git a/gdk/wayland/gdkwayland.h b/gdk/wayland/gdkwayland.h
+index 2b79295add..5f0e9cfa81 100644
+--- a/gdk/wayland/gdkwayland.h
++++ b/gdk/wayland/gdkwayland.h
+@@ -25,6 +25,10 @@
+ #ifndef __GDK_WAYLAND_H__
+ #define __GDK_WAYLAND_H__
+ 
++#ifdef GENTOO_GTK_HIDE_WAYLAND
++  #error "A Gentoo ebuild has hidden wayland and it cannot be used in this compilation unit. Please file a bug if you see this error."
++#endif
++
+ #include <gdk/gdk.h>
+ 
+ #define __GDKWAYLAND_H_INSIDE__
+diff --git a/gdk/x11/gdkx.h b/gdk/x11/gdkx.h
+index 1f64bccb6d..256c83015e 100644
+--- a/gdk/x11/gdkx.h
++++ b/gdk/x11/gdkx.h
+@@ -25,6 +25,10 @@
+ #ifndef __GDK_X_H__
+ #define __GDK_X_H__
+ 
++#ifdef GENTOO_GTK_HIDE_X11
++  #error "A Gentoo ebuild has hidden x11 and it cannot be used in this compilation unit. Please file a bug if you see this error."
++#endif
++
+ #include <gdk/gdk.h>
+ 
+ #include <X11/Xlib.h>
+-- 
+2.44.2
+
diff --git a/x11-libs/gtk+/gtk+-3.24.41-r1.ebuild b/x11-libs/gtk+/gtk+-3.24.41-r1.ebuild
new file mode 100644
index 000000000000..1bb71ee363f1
--- /dev/null
+++ b/x11-libs/gtk+/gtk+-3.24.41-r1.ebuild
@@ -0,0 +1,205 @@
+# Copyright 1999-2024 Gentoo Authors
+# Distributed under the terms of the GNU General Public License v2
+
+EAPI=8
+
+inherit gnome2 meson-multilib multilib toolchain-funcs virtualx
+
+DESCRIPTION="Gimp ToolKit +"
+HOMEPAGE="https://www.gtk.org/"
+
+LICENSE="LGPL-2+"
+SLOT="3"
+IUSE="aqua broadway cloudproviders colord cups examples gtk-doc +introspection sysprof test vim-syntax wayland +X xinerama"
+REQUIRED_USE="
+	|| ( aqua wayland X )
+	test? ( X )
+	xinerama? ( X )
+"
+RESTRICT="!test? ( test )"
+
+KEYWORDS="~alpha ~amd64 ~arm ~arm64 ~hppa ~ia64 ~loong ~mips ~ppc ~ppc64 ~riscv ~s390 ~sparc ~x86 ~amd64-linux ~x86-linux ~ppc-macos ~x64-solaris"
+
+COMMON_DEPEND="
+	>=app-accessibility/at-spi2-core-2.46.0[introspection?,${MULTILIB_USEDEP}]
+	>=dev-libs/fribidi-0.19.7[${MULTILIB_USEDEP}]
+	>=dev-libs/glib-2.57.2:2[${MULTILIB_USEDEP}]
+	media-libs/fontconfig[${MULTILIB_USEDEP}]
+	>=media-libs/harfbuzz-2.2.0:=
+	>=media-libs/libepoxy-1.4[X(+)?,egl(+),${MULTILIB_USEDEP}]
+	virtual/libintl[${MULTILIB_USEDEP}]
+	>=x11-libs/cairo-1.14[aqua?,glib,svg(+),X?,${MULTILIB_USEDEP}]
+	>=x11-libs/gdk-pixbuf-2.30:2[introspection?,${MULTILIB_USEDEP}]
+	>=x11-libs/pango-1.44.0[introspection?,${MULTILIB_USEDEP}]
+	x11-misc/shared-mime-info
+
+	cloudproviders? ( net-libs/libcloudproviders[${MULTILIB_USEDEP}] )
+	colord? ( >=x11-misc/colord-0.1.9:0=[${MULTILIB_USEDEP}] )
+	cups? ( >=net-print/cups-2.0[${MULTILIB_USEDEP}] )
+	introspection? ( >=dev-libs/gobject-introspection-1.39:= )
+	sysprof? ( >=dev-util/sysprof-capture-3.33.2:3[${MULTILIB_USEDEP}] )
+	wayland? (
+		>=dev-libs/wayland-1.14.91[${MULTILIB_USEDEP}]
+		>=dev-libs/wayland-protocols-1.32
+		media-libs/mesa[wayland,${MULTILIB_USEDEP}]
+		>=x11-libs/libxkbcommon-0.2[${MULTILIB_USEDEP}]
+	)
+	X? (
+		media-libs/libglvnd[X(+),${MULTILIB_USEDEP}]
+		x11-libs/libX11[${MULTILIB_USEDEP}]
+		x11-libs/libXcomposite[${MULTILIB_USEDEP}]
+		x11-libs/libXcursor[${MULTILIB_USEDEP}]
+		x11-libs/libXdamage[${MULTILIB_USEDEP}]
+		x11-libs/libXext[${MULTILIB_USEDEP}]
+		x11-libs/libXfixes[${MULTILIB_USEDEP}]
+		>=x11-libs/libXi-1.8[${MULTILIB_USEDEP}]
+		>=x11-libs/libXrandr-1.5[${MULTILIB_USEDEP}]
+		xinerama? ( x11-libs/libXinerama[${MULTILIB_USEDEP}] )
+	)
+"
+DEPEND="${COMMON_DEPEND}
+	X? ( x11-base/xorg-proto )
+"
+RDEPEND="${COMMON_DEPEND}
+	>=dev-util/gtk-update-icon-cache-3
+"
+# librsvg for svg icons (PDEPEND to avoid circular dep), bug #547710
+PDEPEND="
+	gnome-base/librsvg[${MULTILIB_USEDEP}]
+	>=x11-themes/adwaita-icon-theme-3.14
+	vim-syntax? ( app-vim/gtk-syntax )
+"
+BDEPEND="
+	app-text/docbook-xml-dtd:4.1.2
+	app-text/docbook-xsl-stylesheets
+	dev-libs/gobject-introspection-common
+	dev-libs/libxslt
+	>=dev-util/gdbus-codegen-2.48
+	dev-util/glib-utils
+	>=dev-build/gtk-doc-am-1.20
+	wayland? ( dev-util/wayland-scanner )
+	>=sys-devel/gettext-0.19.7
+	virtual/pkgconfig
+	x11-libs/gdk-pixbuf:2
+	gtk-doc? (
+		app-text/docbook-xml-dtd:4.3
+		>=dev-util/gtk-doc-1.20
+	)
+	test? ( sys-apps/dbus )
+"
+
+MULTILIB_CHOST_TOOLS=(
+	/usr/bin/gtk-query-immodules-3.0$(get_exeext)
+)
+
+PATCHES=(
+	# gtk-update-icon-cache is installed by dev-util/gtk-update-icon-cache
+	"${FILESDIR}"/${PN}-3.24.36-update-icon-cache.patch
+	# Gentoo-specific patch to add a "poison" macro support, allowing other ebuilds
+	# with USE="-wayland -X" to trick gtk into claiming that it wasn't built with
+	# such support.
+	# https://bugs.gentoo.org/624960
+	"${FILESDIR}"/0001-gdk-add-a-poison-macro-to-hide-GDK_WINDOWING_.patch
+)
+
+src_prepare() {
+	default
+
+	# The border-image-excess-size.ui test is known to fail on big-endian platforms
+	# See https://gitlab.gnome.org/GNOME/gtk/-/issues/5904
+	if [[ $(tc-endian) == big ]]; then
+		sed -i \
+			-e "/border-image-excess-size.ui/d" \
+			-e "/^xfails =/a 'border-image-excess-size.ui'," \
+			testsuite/reftests/meson.build || die
+	fi
+}
+
+multilib_src_configure() {
+	local emesonargs=(
+		$(meson_use aqua quartz_backend)
+		$(meson_use broadway broadway_backend)
+		$(meson_use cloudproviders)
+		$(meson_use examples demos)
+		$(meson_use examples)
+		$(meson_native_use_bool gtk-doc gtk_doc)
+		$(meson_native_use_bool introspection)
+		$(meson_use sysprof profiler)
+		$(meson_use wayland wayland_backend)
+		$(meson_use X x11_backend)
+		-Dcolord=$(usex colord yes no)
+		-Dprint_backends=$(usex cups cups,file,lpr file,lpr)
+		-Dxinerama=$(usex xinerama yes no)
+		# Include backend immodules into gtk itself, to avoid problems like
+		# https://gitlab.gnome.org/GNOME/gnome-shell/issues/109 from a
+		# user overridden GTK_IM_MODULE envvar
+		-Dbuiltin_immodules=backend
+		-Dman=true
+		$(meson_use test tests)
+		-Dtracker3=false
+	)
+	meson_src_configure
+}
+
+multilib_src_compile() {
+	meson_src_compile
+}
+
+multilib_src_test() {
+	virtx dbus-run-session meson test -C "${BUILD_DIR}" --timeout-multiplier 4 || die
+}
+
+multilib_src_install() {
+	meson_src_install
+}
+
+multilib_src_install_all() {
+	insinto /etc/gtk-3.0
+	doins "${FILESDIR}"/settings.ini
+	# Skip README.win32.md that would get installed by default
+	DOCS=( NEWS README.md )
+	einstalldocs
+}
+
+pkg_preinst() {
+	gnome2_pkg_preinst
+
+	multilib_pkg_preinst() {
+		# Make immodules.cache belongs to gtk+ alone
+		local cache="/usr/$(get_libdir)/gtk-3.0/3.0.0/immodules.cache"
+
+		if [[ -e ${EROOT}${cache} ]]; then
+			cp "${EROOT}${cache}" "${ED}${cache}" || die
+		else
+			touch "${ED}${cache}" || die
+		fi
+	}
+	multilib_parallel_foreach_abi multilib_pkg_preinst
+}
+
+pkg_postinst() {
+	gnome2_pkg_postinst
+
+	multilib_pkg_postinst() {
+		gnome2_query_immodules_gtk3 \
+			|| die "Update immodules cache failed (for ${ABI})"
+	}
+	multilib_parallel_foreach_abi multilib_pkg_postinst
+
+	if ! has_version "app-text/evince"; then
+		elog "Please install app-text/evince for print preview functionality."
+		elog "Alternatively, check \"gtk-print-preview-command\" documentation and"
+		elog "add it to your settings.ini file."
+	fi
+}
+
+pkg_postrm() {
+	gnome2_pkg_postrm
+
+	if [[ -z ${REPLACED_BY_VERSION} ]]; then
+		multilib_pkg_postrm() {
+			rm -f "${EROOT}/usr/$(get_libdir)/gtk-3.0/3.0.0/immodules.cache"
+		}
+		multilib_foreach_abi multilib_pkg_postrm
+	fi
+}
diff --git a/x11-libs/gtk+/gtk+-3.24.42.ebuild b/x11-libs/gtk+/gtk+-3.24.42-r1.ebuild
index 655c05a8a518..b87f4ebae8bb 100644
--- a/x11-libs/gtk+/gtk+-3.24.42.ebuild
+++ b/x11-libs/gtk+/gtk+-3.24.42-r1.ebuild
@@ -95,6 +95,11 @@ MULTILIB_CHOST_TOOLS=(
 PATCHES=(
 	# gtk-update-icon-cache is installed by dev-util/gtk-update-icon-cache
 	"${FILESDIR}"/${PN}-3.24.36-update-icon-cache.patch
+	# Gentoo-specific patch to add a "poison" macro support, allowing other ebuilds
+	# with USE="-wayland -X" to trick gtk into claiming that it wasn't built with
+	# such support.
+	# https://bugs.gentoo.org/624960
+	"${FILESDIR}"/0001-gdk-add-a-poison-macro-to-hide-GDK_WINDOWING_.patch
 )
 
 src_prepare() {