From 8472cf8bbe4d57d18bce7522070aa1cf9be7fabd Mon Sep 17 00:00:00 2001
From: Simon Duquennoy <simon.duquennoy@ri.se>
Date: Sat, 13 Oct 2018 10:17:30 +0200
Subject: [PATCH] stimer_reset: do not do anything if the timer has not expired

---
 os/sys/stimer.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/os/sys/stimer.c b/os/sys/stimer.c
index 1301dc41e..007587e83 100644
--- a/os/sys/stimer.c
+++ b/os/sys/stimer.c
@@ -77,7 +77,8 @@ stimer_set(struct stimer *t, unsigned long interval)
  * given to the stimer_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
- * stimer_restart() function.
+ * stimer_restart() function. If this is executed before the
+ * timer expired, this function has no effect.
  *
  * \param t A pointer to the timer.
  *
@@ -86,7 +87,9 @@ stimer_set(struct stimer *t, unsigned long interval)
 void
 stimer_reset(struct stimer *t)
 {
-  t->start += t->interval;
+  if(stimer_expired(t)) {
+    t->start += t->interval;
+  }
 }
 /*---------------------------------------------------------------------------*/
 /**