From edcf891e47f5c80e802428956cbc88ab802758c6 Mon Sep 17 00:00:00 2001
From: Paul Bergeron <paul.d.bergeron@gmail.com>
Date: Sat, 27 Feb 2016 13:35:50 -0800
Subject: [PATCH] Add ContentSize() to cheaply calculate the size of the ring
 buffer

---
 ring.go | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/ring.go b/ring.go
index 2214c4b..3564555 100644
--- a/ring.go
+++ b/ring.go
@@ -35,6 +35,21 @@ func (r Ring) Capacity() int {
 	return len(r.buff)
 }
 
+/*
+ContentSize returns the current number of elements inside the ring buffer.
+*/
+func (r *Ring) ContentSize() int {
+	if r.head == -1 {
+		return 0
+	} else {
+		difference := (r.head - r.tail)
+		if difference < 0 {
+			difference = -difference
+		}
+		return difference + 1
+	}
+}
+
 /*
 Enqueue a value into the Ring buffer.
 */