From 163d1241b3bdb5875c9235c0a539b7121fb60177 Mon Sep 17 00:00:00 2001
From: Simon Duquennoy <simon.duquennoy@ri.se>
Date: Fri, 25 May 2018 07:03:22 -0700
Subject: [PATCH] timer_reset: do not do anything if the timer has not expired

---
 os/sys/timer.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/os/sys/timer.c b/os/sys/timer.c
index 1eeae64de..b99aa4127 100644
--- a/os/sys/timer.c
+++ b/os/sys/timer.c
@@ -74,9 +74,8 @@ timer_set(struct timer *t, clock_time_t interval)
  * given to the timer_set() function. The start point of the interval
  * is the exact time that the timer last expired. Therefore, this
  * function will cause the timer to be stable over time, unlike the
- * timer_restart() function.
- *
- * \note Must not be executed before timer expired
+ * timer_restart() function. If this is executed before the
+ * timer expired, this function has no effect.
  *
  * \param t A pointer to the timer.
  * \sa timer_restart()
@@ -84,7 +83,9 @@ timer_set(struct timer *t, clock_time_t interval)
 void
 timer_reset(struct timer *t)
 {
-  t->start += t->interval;
+  if(timer_expired(t)) {
+    t->start += t->interval;
+  }
 }
 /*---------------------------------------------------------------------------*/
 /**