surface: add wlr_surface_role.precommit

This allows to emit the unmap event before the surface becomes
actually unmapped for most shells.

1 files changed, 18 insertions, 0 deletions

diff --git a/xwayland/xwm.c b/xwayland/xwm.c
index bee3a005..54cb88d0 100644
--- a/xwayland/xwm.c
+++ b/xwayland/xwm.c
@@ -652,9 +652,27 @@ static void xwayland_surface_role_commit(struct wlr_surface *wlr_surface) {
 	}
 }
 
+static void xwayland_surface_role_precommit(struct wlr_surface *wlr_surface) {
+	assert(wlr_surface->role == &xwayland_surface_role);
+	struct wlr_xwayland_surface *surface = wlr_surface->role_data;
+	if (surface == NULL) {
+		return;
+	}
+
+	if (wlr_surface->pending.committed & WLR_SURFACE_STATE_BUFFER &&
+			wlr_surface->pending.buffer_resource == NULL) {
+		// This is a NULL commit
+		if (surface->mapped) {
+			wlr_signal_emit_safe(&surface->events.unmap, surface);
+			surface->mapped = false;
+		}
+	}
+}
+
 static const struct wlr_surface_role xwayland_surface_role = {
 	.name = "wlr_xwayland_surface",
 	.commit = xwayland_surface_role_commit,
+	.precommit = xwayland_surface_role_precommit,
 };
 
 static void handle_surface_destroy(struct wl_listener *listener, void *data) {