rate_ctr: Add rate_ctr_add2() similar to rate_ctr_inc2()

The convenience wrapper relieves the caller from manually resolving
the individual counter, and instead specify just the counter group
and the index.

Change-Id: If93e8b4fb0b86a87358f32d2b45438ca1887e9f3
---
M include/osmocom/core/rate_ctr.h
1 file changed, 22 insertions(+), 0 deletions(-)

diff --git a/include/osmocom/core/rate_ctr.h b/include/osmocom/core/rate_ctr.h
index d944cc0..0a3eb2c 100644
--- a/include/osmocom/core/rate_ctr.h
+++ b/include/osmocom/core/rate_ctr.h
@@ -86,6 +86,15 @@
  *  \param inc quantity to increment \a ctr by */
 void rate_ctr_add(struct rate_ctr *ctr, int inc);
 
+/*! Increment the counter by \a inc
+ *  \param ctrg \ref rate_ctr_group of counter
+ *  \param idx index into \a ctrg counter group
+ *  \param inc quantity to increment \a ctr by */
+static inline void rate_ctr_add2(struct rate_ctr_group *ctrg, unsigned int idx, int inc)
+{
+	rate_ctr_add(rate_ctr_group_get_ctr(ctrg, idx), inc);
+}
+
 /*! Increment the counter by 1
  *  \param ctr \ref rate_ctr to increment */
 static inline void rate_ctr_inc(struct rate_ctr *ctr)

