Revert "Revert "Merge pull request #1194 from ascent12/meson_feature""

This reverts commit 9c886f20b9.

xwayland/meson.build

@@ -1,3 +1,32 @@
+xwayland_libs = []
+xwayland_required = [
+	'xcb',
+	'xcb-composite',
+	'xcb-render',
+	'xcb-xfixes',
+]
+xwayland_optional = [
+	'xcb-errors',
+	'xcb-icccm',
+]
+
+foreach lib : xwayland_required
+	dep = dependency(lib, required: get_option('xwayland'))
+	if not dep.found()
+		subdir_done()
+	endif
+
+	xwayland_libs += dep
+endforeach
+
+foreach lib : xwayland_optional
+	dep = dependency(lib, required: get_option(lib))
+	if dep.found()
+		xwayland_libs += dep
+		conf_data.set('WLR_HAS_' + lib.underscorify().to_upper(), true)
+	endif
+endforeach
+
 lib_wlr_xwayland = static_library(
 	'wlr_xwayland',
 	files(
@@ -12,14 +41,11 @@ lib_wlr_xwayland = static_library(
 	include_directories: wlr_inc,
 	dependencies: [
 		wayland_server,
-		xcb,
-		xcb_composite,
-		xcb_xfixes,
-		xcb_image,
-		xcb_render,
-		xcb_icccm,
-		xcb_errors,
+		xwayland_libs,
 		xkbcommon,
 		pixman,
 	],
 )
+
+wlr_parts += lib_wlr_xwayland
+conf_data.set('WLR_HAS_XWAYLAND', true)