1 files changed, 50 insertions, 0 deletions
diff --git a/lib/base/dependencygraph.cpp b/lib/base/dependencygraph.cpp
new file mode 100644
index 0000000..025eb3e
--- /dev/null
+++ b/lib/base/dependencygraph.cpp
@@ -0,0 +1,50 @@
+/* Icinga 2 | (c) 2012 Icinga GmbH | GPLv2+ */
+
+#include "base/dependencygraph.hpp"
+
+using namespace icinga;
+
+std::mutex DependencyGraph::m_Mutex;
+std::map<Object *, std::map<Object *, int> > DependencyGraph::m_Dependencies;
+
+void DependencyGraph::AddDependency(Object *parent, Object *child)
+{
+	std::unique_lock<std::mutex> lock(m_Mutex);
+	m_Dependencies[child][parent]++;
+}
+
+void DependencyGraph::RemoveDependency(Object *parent, Object *child)
+{
+	std::unique_lock<std::mutex> lock(m_Mutex);
+
+	auto& refs = m_Dependencies[child];
+	auto it = refs.find(parent);
+
+	if (it == refs.end())
+		return;
+
+	it->second--;
+
+	if (it->second == 0)
+		refs.erase(it);
+
+	if (refs.empty())
+		m_Dependencies.erase(child);
+}
+
+std::vector<Object::Ptr> DependencyGraph::GetParents(const Object::Ptr& child)
+{
+	std::vector<Object::Ptr> objects;
+
+	std::unique_lock<std::mutex> lock(m_Mutex);
+	auto it = m_Dependencies.find(child.get());
+
+	if (it != m_Dependencies.end()) {
+		typedef std::pair<Object *, int> kv_pair;
+		for (const kv_pair& kv : it->second) {
+			objects.emplace_back(kv.first);
+		}
+	}
+
+	return objects;
+}