[clock]添加 rt_tick_get_delta 函数

2 files changed, 17 insertions, 0 deletions

diff --git a/include/rtthread.h b/include/rtthread.h
index a1c0e77a03..103e26e894 100644
--- a/include/rtthread.h
+++ b/include/rtthread.h
@@ -98,6 +98,7 @@ void rt_object_put_sethook(void (*hook)(struct rt_object *object));
  * clock & timer interface
  */
 rt_tick_t rt_tick_get(void);
+rt_tick_t rt_tick_get_delta(rt_tick_t base);
 void rt_tick_set(rt_tick_t tick);
 void rt_tick_increase(void);
 void rt_tick_increase_tick(rt_tick_t tick);
diff --git a/src/clock.c b/src/clock.c
index 3481f22c61..4277fadc0c 100644
--- a/src/clock.c
+++ b/src/clock.c
@@ -74,6 +74,22 @@ rt_tick_t rt_tick_get(void)
 RTM_EXPORT(rt_tick_get);
 
 /**
+ * @brief    This function will return delta tick from base.
+ *
+ * @param    base to consider
+ * 
+ * @return   Return delta tick.
+ */
+rt_tick_t rt_tick_get_delta(rt_tick_t base)
+{
+    rt_tick_t tnow = rt_tick_get();
+    if (tnow >= base)
+        return tnow - base;
+    return RT_TICK_MAX - base + tnow + 1;
+}
+RTM_EXPORT(rt_tick_get_delta);
+
+/**
  * @brief    This function will set current tick.
  *
  * @param    tick is the value that you will set.