backend/session: wire up openbsd support

backend/session/meson.build

@@ -1,18 +1,27 @@
-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()
+
+platform = target_machine.system()
+if platform == 'linux' or platform == 'freebsd'
+	libudev = dependency('libudev', required: session_required)
+	if not (libudev.found() and libseat.found())
+		subdir_done()
+	endif
+
+	wlr_files += files('session_libudev.c')
+	wlr_deps += libudev
+elif platform == 'openbsd'
+	wlr_files += files('session_openbsd.c')
+else
+	error('Unsupported platform')
 endif
 
 wlr_files += files('session.c')
-wlr_files += files('session_libudev.c')
-wlr_deps += [udev, libseat]
+wlr_deps += libseat
 features += { 'session': true }
+

backend/session/session_openbsd.c

@@ -0,0 +1,41 @@
+#include <fcntl.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <stdbool.h>
+#include "backend/session/session.h"
+
+struct drm_event_monitor {
+	int fd;
+};
+
+// TODO: use kqueue NOTE_CHANGE mechanism
+struct drm_event_monitor *monitor_drm_events(int *fd) {
+	struct drm_event_monitor *ctx = calloc(1, sizeof(struct drm_event_monitor));
+	if (!ctx) {
+		return NULL;
+	}
+	ctx->fd = open("/dev/null", O_RDONLY);
+	if (ctx->fd == -1) {
+		free(ctx);
+		return NULL;
+	}
+	*fd = ctx->fd;
+	return ctx;
+}
+void drm_event_monitor_free(struct drm_event_monitor *ctx) {
+	close(ctx->fd);
+	free(ctx);
+}
+
+int receive_drm_device(struct drm_event_monitor *ctx,
+		struct drm_event_content *ev) {
+	return -1;
+}
+
+const char *get_device_seat(struct drm_event_monitor *ctx, const char *devnode) {
+	return NULL;
+}
+
+bool is_drm_device_primary(struct drm_event_monitor *ctx, const char *devnode) {
+	return false;
+}