From 9b77aac5426cac86d44150441a3131e4d7051151 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Moritz=20=27Morty=27=20Str=C3=BCbe?= <morty@gmx.net>
Date: Fri, 2 Nov 2012 16:56:11 +0100
Subject: [PATCH] Add function etimer_reset_set. This new function is similar
 to reset, but allows to also set a new timeout. Thus long-term accuracy with
 changing timeouts is now possible.

---
 core/sys/etimer.c |  8 ++++++++
 core/sys/etimer.h | 13 +++++++++++++
 2 files changed, 21 insertions(+)

diff --git a/core/sys/etimer.c b/core/sys/etimer.c
index 719401115..17ac74285 100644
--- a/core/sys/etimer.c
+++ b/core/sys/etimer.c
@@ -181,6 +181,14 @@ etimer_set(struct etimer *et, clock_time_t interval)
 }
 /*---------------------------------------------------------------------------*/
 void
+etimer_reset_with_new_interval(struct etimer *et, clock_time_t interval)
+{
+  timer_reset(&et->timer);
+  et->timer.interval = interval;
+  add_timer(et);
+}
+/*---------------------------------------------------------------------------*/
+void
 etimer_reset(struct etimer *et)
 {
   timer_reset(&et->timer);
diff --git a/core/sys/etimer.h b/core/sys/etimer.h
index b1f57b01a..ebbcfc7fd 100644
--- a/core/sys/etimer.h
+++ b/core/sys/etimer.h
@@ -114,6 +114,19 @@ CCIF void etimer_set(struct etimer *et, clock_time_t interval);
  */
 CCIF void etimer_reset(struct etimer *et);
 
+/**
+ * \brief      Reset an event timer with a new interval.
+ * \param et   A pointer to the event timer.
+ * \param interval The interval before the timer expires.
+ *
+ *             This function very similar to etimer_reset. Opposed to
+ *             etimer_reset it is possible to change the timout.
+ *             This allows accurate, non-periodic timers without drift.
+ *
+ * \sa etimer_reset()
+ */
+void etimer_reset_with_new_interval(struct etimer *et, clock_time_t interval);
+
 /**
  * \brief      Restart an event timer from the current point in time
  * \param et   A pointer to the event timer.