+static int file_of_seat(const char *seat, char **_p) {
+ char *p;
+ int r;
+
+ assert(_p);
+
+ if (seat)
+ p = strappend("/run/systemd/seats/", seat);
+ else {
+ char *buf;
+
+ r = sd_session_get_seat(NULL, &buf);
+ if (r < 0)
+ return r;
+
+ p = strappend("/run/systemd/seats/", buf);
+ free(buf);
+ }
+
+ if (!p)
+ return -ENOMEM;
+
+ *_p = p;
+ return 0;
+}
+