really rely on autoconf

ev.c

@@ -43,26 +43,43 @@ extern "C" {
 #  ifndef EV_USE_REALTIME
 #   define EV_USE_REALTIME  1
 #  endif
+# else
+#  ifndef EV_USE_MONOTONIC
+#   define EV_USE_MONOTONIC 0
+#  endif
+#  ifndef EV_USE_REALTIME
+#   define EV_USE_REALTIME  0
+#  endif
 # endif
 
 # if HAVE_SELECT && HAVE_SYS_SELECT_H && !defined (EV_USE_SELECT)
 #  define EV_USE_SELECT 1
+# else
+#  define EV_USE_SELECT 0
 # endif
 
 # if HAVE_POLL && HAVE_POLL_H && !defined (EV_USE_POLL)
 #  define EV_USE_POLL 1
+# else
+#  define EV_USE_POLL 0
 # endif
 
 # if HAVE_EPOLL_CTL && HAVE_SYS_EPOLL_H && !defined (EV_USE_EPOLL)
 #  define EV_USE_EPOLL 1
+# else
+#  define EV_USE_EPOLL 0
 # endif
 
 # if HAVE_KQUEUE && HAVE_SYS_EVENT_H && HAVE_SYS_QUEUE_H && !defined (EV_USE_KQUEUE)
 #  define EV_USE_KQUEUE 1
+# else
+#  define EV_USE_KQUEUE 0
 # endif
 
 # if HAVE_PORT_H && HAVE_PORT_CREATE && !defined (EV_USE_PORT)
 #  define EV_USE_PORT 1
+# else
+#  define EV_USE_PORT 0
 # endif
 
 #endif