bgpd: improve "monotonic" uptime correction

Older versions of Quagga/Zebra would output a value in MRT table
dump files for "uptime" aka "ORIGINATED" that was a WALL clock
value.  Given that uptime is now internally a bgp_clock MONOTONIC
value, the output in the MRT files is showing up as monotonic.

Note: time of MRT dump is still recorded correctly as a
time() based value, so we haven't lost that value.

Proposal is to correct the uptime output on the vty and in the
MRT files to again display something more akin to WALL time.

* bgp_dump.c: (bgp_dump_routes_func) add conditional correction
* bgp_route.c: (route_vty_out_detail) make correction conditional, move
  variable declaration to beginning of the function

1 files changed, 8 insertions, 1 deletions

diff --git a/bgpd/bgp_route.c b/bgpd/bgp_route.c
index cf8e2113..b7716330 100644
--- a/bgpd/bgp_route.c
+++ b/bgpd/bgp_route.c
@@ -5799,6 +5799,9 @@ route_vty_out_detail (struct vty *vty, struct bgp *bgp, struct prefix *p,
   char buf1[BUFSIZ];
   struct attr *attr;
   int sockunion_vty_out (struct vty *, union sockunion *);
+#ifdef HAVE_CLOCK_MONOTONIC
+  time_t tbuf;
+#endif
 	
   attr = binfo->attr;
 
@@ -5954,8 +5957,12 @@ route_vty_out_detail (struct vty *vty, struct bgp *bgp, struct prefix *p,
 	bgp_damp_info_vty (vty, binfo);
 
       /* Line 7 display Uptime */
-      time_t tbuf = time(NULL) - (bgp_clock() - binfo->uptime);
+#ifdef HAVE_CLOCK_MONOTONIC
+      tbuf = time(NULL) - (bgp_clock() - binfo->uptime);
       vty_out (vty, "      Last update: %s", ctime(&tbuf));
+#else
+      vty_out (vty, "      Last update: %s", ctime(&binfo->uptime));
+#endif /* HAVE_CLOCK_MONOTONIC */
     }
   vty_out (vty, "%s", VTY_NEWLINE);
 }