u/system_helpers: Make system devices easier to embed

src/xrt/auxiliary/util/u_system_helpers.c

@@ -26,15 +26,8 @@
 static void
 destroy(struct xrt_system_devices *xsysd)
 {
-	struct u_system_devices *usysd = u_system_devices(xsysd);
-
-	for (uint32_t i = 0; i < ARRAY_SIZE(usysd->base.xdevs); i++) {
-		xrt_device_destroy(&usysd->base.xdevs[i]);
-	}
-
-	xrt_frame_context_destroy_nodes(&usysd->xfctx);
-
-	free(usysd);
+	u_system_devices_close(xsysd);
+	free(xsysd);
 }
 
 
@@ -53,6 +46,18 @@ u_system_devices_allocate(void)
 	return usysd;
 }
 
+void
+u_system_devices_close(struct xrt_system_devices *xsysd)
+{
+	struct u_system_devices *usysd = u_system_devices(xsysd);
+
+	for (uint32_t i = 0; i < ARRAY_SIZE(usysd->base.xdevs); i++) {
+		xrt_device_destroy(&usysd->base.xdevs[i]);
+	}
+
+	xrt_frame_context_destroy_nodes(&usysd->xfctx);
+}
+
 xrt_result_t
 u_system_devices_create_from_prober(struct xrt_instance *xinst,
                                     struct xrt_system_devices **out_xsysd,

src/xrt/auxiliary/util/u_system_helpers.h

@@ -61,6 +61,16 @@ u_system_devices(struct xrt_system_devices *xsysd)
 struct u_system_devices *
 u_system_devices_allocate(void);
 
+/*!
+ * Destroys all devices and clears out the frame context, doesn't free the
+ * struct itself, useful for code embedding the system devices struct into
+ * other objects where it's not the first member or C++ classes.
+ *
+ * @ingroup aux_util
+ */
+void
+u_system_devices_close(struct xrt_system_devices *xsysd);
+
 /*!
  * Takes a @ref xrt_instance, gets the prober from it and then uses the prober
  * to allocate a filled in @ref u_system_devices.