From 41c43fd837e82f9181bdd4685b7cd79fcfa5943d Mon Sep 17 00:00:00 2001
From: smlng <s@mlng.net>
Date: Wed, 19 Apr 2017 17:19:27 +0200
Subject: [PATCH] rpl: make parent lifetime consistent with other timers

---
 sys/net/gnrc/routing/rpl/gnrc_rpl.c       | 15 +++++++--------
 sys/net/gnrc/routing/rpl/gnrc_rpl_dodag.c |  3 +--
 sys/shell/commands/sc_gnrc_rpl.c          |  3 +--
 3 files changed, 9 insertions(+), 12 deletions(-)

diff --git a/sys/net/gnrc/routing/rpl/gnrc_rpl.c b/sys/net/gnrc/routing/rpl/gnrc_rpl.c
index d2df979023..10bd8526cc 100644
--- a/sys/net/gnrc/routing/rpl/gnrc_rpl.c
+++ b/sys/net/gnrc/routing/rpl/gnrc_rpl.c
@@ -252,23 +252,22 @@ static void *_event_loop(void *args)
 
 void _update_lifetime(void)
 {
-    uint32_t now = xtimer_now_usec();
-    uint16_t now_sec = now / US_PER_SEC;
-
     gnrc_rpl_parent_t *parent;
     gnrc_rpl_instance_t *inst;
 
     for (uint8_t i = 0; i < GNRC_RPL_PARENTS_NUMOF; ++i) {
         parent = &gnrc_rpl_parents[i];
         if (parent->state != 0) {
-            if ((int32_t)(parent->lifetime - now_sec) <= GNRC_RPL_LIFETIME_UPDATE_STEP) {
+            if (parent->lifetime > GNRC_RPL_LIFETIME_UPDATE_STEP) {
+                if (parent->lifetime > (2 * GNRC_RPL_LIFETIME_UPDATE_STEP)) {
+                    gnrc_rpl_send_DIS(parent->dodag->instance, &parent->addr);
+                }
+                parent->lifetime -= GNRC_RPL_LIFETIME_UPDATE_STEP;
+            }
+            else {
                 gnrc_rpl_dodag_t *dodag = parent->dodag;
                 gnrc_rpl_parent_remove(parent);
                 gnrc_rpl_parent_update(dodag, NULL);
-                continue;
-            }
-            else if ((int32_t)(parent->lifetime - now_sec) <= (GNRC_RPL_LIFETIME_UPDATE_STEP * 2)) {
-                gnrc_rpl_send_DIS(parent->dodag->instance, &parent->addr);
             }
         }
     }
diff --git a/sys/net/gnrc/routing/rpl/gnrc_rpl_dodag.c b/sys/net/gnrc/routing/rpl/gnrc_rpl_dodag.c
index 3a8c1ff9c9..04cdf16cc7 100644
--- a/sys/net/gnrc/routing/rpl/gnrc_rpl_dodag.c
+++ b/sys/net/gnrc/routing/rpl/gnrc_rpl_dodag.c
@@ -265,8 +265,7 @@ void gnrc_rpl_parent_update(gnrc_rpl_dodag_t *dodag, gnrc_rpl_parent_t *parent)
 {
     /* update Parent lifetime */
     if (parent != NULL) {
-        uint32_t now = xtimer_now_usec();
-        parent->lifetime = (now / US_PER_SEC) + (dodag->default_lifetime * dodag->lifetime_unit);
+        parent->lifetime = dodag->default_lifetime * dodag->lifetime_unit;
 #ifdef MODULE_GNRC_RPL_P2P
         if (dodag->instance->mop != GNRC_RPL_P2P_MOP) {
 #endif
diff --git a/sys/shell/commands/sc_gnrc_rpl.c b/sys/shell/commands/sc_gnrc_rpl.c
index 67062f2f8f..a10b5f5ca8 100644
--- a/sys/shell/commands/sc_gnrc_rpl.c
+++ b/sys/shell/commands/sc_gnrc_rpl.c
@@ -304,8 +304,7 @@ int _gnrc_rpl_dodag_show(void)
         LL_FOREACH(gnrc_rpl_instances[i].dodag.parents, parent) {
             printf("\t\tparent [addr: %s | rank: %d | lifetime: %" PRIu32 "s]\n",
                     ipv6_addr_to_str(addr_str, &parent->addr, sizeof(addr_str)),
-                    parent->rank, ((int32_t) (parent->lifetime - (((uint32_t) xnow / US_PER_SEC))))
-                    < 0 ? 0 : (parent->lifetime - ((uint32_t) xnow / US_PER_SEC)));
+                    parent->rank, parent->lifetime);
         }
     }
     return 0;