1 files changed, 40 insertions, 0 deletions
diff --git a/lib/livestatus/stdaggregator.cpp b/lib/livestatus/stdaggregator.cpp
new file mode 100644
index 0000000..99c3a8e
--- /dev/null
+++ b/lib/livestatus/stdaggregator.cpp
@@ -0,0 +1,40 @@
+/* Icinga 2 | (c) 2012 Icinga GmbH | GPLv2+ */
+
+#include "livestatus/stdaggregator.hpp"
+#include <math.h>
+
+using namespace icinga;
+
+StdAggregator::StdAggregator(String attr)
+	: m_StdAttr(std::move(attr))
+{ }
+
+StdAggregatorState *StdAggregator::EnsureState(AggregatorState **state)
+{
+	if (!*state)
+		*state = new StdAggregatorState();
+
+	return static_cast<StdAggregatorState *>(*state);
+}
+
+void StdAggregator::Apply(const Table::Ptr& table, const Value& row, AggregatorState **state)
+{
+	Column column = table->GetColumn(m_StdAttr);
+
+	Value value = column.ExtractValue(row);
+
+	StdAggregatorState *pstate = EnsureState(state);
+
+	pstate->StdSum += value;
+	pstate->StdQSum += pow(value, 2);
+	pstate->StdCount++;
+}
+
+double StdAggregator::GetResultAndFreeState(AggregatorState *state) const
+{
+	StdAggregatorState *pstate = EnsureState(&state);
+	double result = sqrt((pstate->StdQSum - (1 / pstate->StdCount) * pow(pstate->StdSum, 2)) / (pstate->StdCount - 1));
+	delete pstate;
+
+	return result;
+}