backend/session: make optional

Some compositors are not interested in wlr_session, for instance
nested compositors.

Disabling wlr_session removes the udev dependency.

1 files changed, 10 insertions, 1 deletions

diff --git a/backend/session/meson.build b/backend/session/meson.build
index 9e35ef1e..4c20ee9d 100644
--- a/backend/session/meson.build
+++ b/backend/session/meson.build
@@ -1,8 +1,17 @@
+msg = 'Required for session support.'
+udev = dependency('libudev', required: session_required, not_found_message: msg)
 libseat = dependency(
 	'libseat',
 	version: '>=0.2.0',
 	fallback: 'seatd',
 	default_options: ['server=disabled', 'man-pages=disabled', 'examples=disabled'],
+	required: session_required,
+	not_found_message: msg,
 )
+if not (udev.found() and libseat.found())
+	subdir_done()
+endif
+
 wlr_files += files('session.c')
-wlr_deps += libseat
+wlr_deps += [udev, libseat]
+features += { 'session': true }