From c10f0a639b6aa63fa35e6f79b789538b613ed18c Mon Sep 17 00:00:00 2001
From: Noah Hilverling <noah.hilverling@icinga.com>
Date: Tue, 14 Nov 2017 11:03:05 +0100
Subject: [PATCH] RingBuffer: Add CalculateRate()

refs #5750
---
 lib/base/ringbuffer.cpp | 18 ++++++++++++++++--
 lib/base/ringbuffer.hpp |  2 ++
 2 files changed, 18 insertions(+), 2 deletions(-)

diff --git a/lib/base/ringbuffer.cpp b/lib/base/ringbuffer.cpp
index b8bcce93b..4e023e7ab 100644
--- a/lib/base/ringbuffer.cpp
+++ b/lib/base/ringbuffer.cpp
@@ -20,11 +20,12 @@
 #include "base/ringbuffer.hpp"
 #include "base/objectlock.hpp"
 #include "base/utility.hpp"
+#include <algorithm>
 
 using namespace icinga;
 
 RingBuffer::RingBuffer(RingBuffer::SizeType slots)
-	: Object(), m_Slots(slots, 0), m_TimeValue(0)
+	: Object(), m_Slots(slots, 0), m_TimeValue(0), m_InsertedValues(0)
 { }
 
 RingBuffer::SizeType RingBuffer::GetLength(void) const
@@ -40,6 +41,9 @@ void RingBuffer::InsertValue(RingBuffer::SizeType tv, int num)
 
 	RingBuffer::SizeType offsetTarget = tv % m_Slots.size();
 
+	if (m_TimeValue == 0)
+		m_InsertedValues = 1;
+
 	if (tv > m_TimeValue) {
 		RingBuffer::SizeType offset = m_TimeValue % m_Slots.size();
 
@@ -51,6 +55,9 @@ void RingBuffer::InsertValue(RingBuffer::SizeType tv, int num)
 				offset = 0;
 
 			m_Slots[offset] = 0;
+
+			if (m_TimeValue != 0 && m_InsertedValues < m_Slots.size())
+				m_InsertedValues++;
 		}
 
 		m_TimeValue = tv;
@@ -68,7 +75,7 @@ int RingBuffer::UpdateAndGetValues(RingBuffer::SizeType tv, RingBuffer::SizeType
 	if (span > m_Slots.size())
 		span = m_Slots.size();
 
-	int off = m_TimeValue % m_Slots.size();;
+	int off = m_TimeValue % m_Slots.size();
 	int sum = 0;
 	while (span > 0) {
 		sum += m_Slots[off];
@@ -82,3 +89,10 @@ int RingBuffer::UpdateAndGetValues(RingBuffer::SizeType tv, RingBuffer::SizeType
 
 	return sum;
 }
+
+double RingBuffer::CalculateRate(RingBuffer::SizeType tv, RingBuffer::SizeType span)
+{
+	ObjectLock olock(this);
+	int sum = UpdateAndGetValues(tv, span);
+	return sum / static_cast<double>(std::min(span, m_InsertedValues));
+}
diff --git a/lib/base/ringbuffer.hpp b/lib/base/ringbuffer.hpp
index 94063c563..d81515858 100644
--- a/lib/base/ringbuffer.hpp
+++ b/lib/base/ringbuffer.hpp
@@ -44,10 +44,12 @@ public:
 	SizeType GetLength(void) const;
 	void InsertValue(SizeType tv, int num);
 	int UpdateAndGetValues(SizeType tv, SizeType span);
+	double CalculateRate(SizeType tv, SizeType span);
 
 private:
 	std::vector<int> m_Slots;
 	SizeType m_TimeValue;
+	SizeType m_InsertedValues;
 };
 
 }
-- 
2.40.0