+static int swap_get_timeout(Unit *u, uint64_t *timeout) {
+ Swap *s = SWAP(u);
+ int r;
+
+ if (!s->timer_event_source)
+ return 0;
+
+ r = sd_event_source_get_time(s->timer_event_source, timeout);
+ if (r < 0)
+ return r;
+
+ return 1;
+}
+
+static bool swap_supported(Manager *m) {
+ static int supported = -1;
+
+ /* If swap support is not available in the kernel, or we are
+ * running in a container we don't support swap units, and any
+ * attempts to starting one should fail immediately. */
+
+ if (supported < 0)
+ supported =
+ access("/proc/swaps", F_OK) >= 0 &&
+ detect_container(NULL) <= 0;
+
+ return supported;
+}
+