forked from cawka/ndn.cxx
diff --git a/ndn-cpp/trie/policies/lru-policy.h b/ndn-cpp/trie/policies/lru-policy.h
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+++ b/ndn-cpp/trie/policies/lru-policy.h
@@ -0,0 +1,124 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil -*- */
+/*
+ * Copyright (c) 2013, Regents of the University of California
+ * Alexander Afanasyev
+ *
+ * BSD license, See the LICENSE file for more information
+ *
+ * Author: Alexander Afanasyev <alexander.afanasyev@ucla.edu>
+ */
+
+#ifndef LRU_POLICY_H_
+#define LRU_POLICY_H_
+
+#include <boost/intrusive/options.hpp>
+#include <boost/intrusive/list.hpp>
+
+namespace ndn {
+namespace trie {
+
+/**
+ * @brief Traits for Least Recently Used replacement policy
+ */
+struct lru_policy_traits
+{
+ /// @brief Name that can be used to identify the policy (e.g., for logging)
+ static std::string GetName () { return "Lru"; }
+
+ struct policy_hook_type : public boost::intrusive::list_member_hook<> {};
+
+ template<class Container>
+ struct container_hook
+ {
+ typedef boost::intrusive::member_hook< Container,
+ policy_hook_type,
+ &Container::policy_hook_ > type;
+ };
+
+ template<class Base,
+ class Container,
+ class Hook>
+ struct policy
+ {
+ typedef typename boost::intrusive::list< Container, Hook > policy_container;
+
+ // could be just typedef
+ class type : public policy_container
+ {
+ public:
+ typedef Container parent_trie;
+
+ type (Base &base)
+ : base_ (base)
+ , max_size_ (100)
+ {
+ }
+
+ inline void
+ update (typename parent_trie::iterator item)
+ {
+ // do relocation
+ policy_container::splice (policy_container::end (),
+ *this,
+ policy_container::s_iterator_to (*item));
+ }
+
+ inline bool
+ insert (typename parent_trie::iterator item)
+ {
+ if (max_size_ != 0 && policy_container::size () >= max_size_)
+ {
+ base_.erase (&(*policy_container::begin ()));
+ }
+
+ policy_container::push_back (*item);
+ return true;
+ }
+
+ inline void
+ lookup (typename parent_trie::iterator item)
+ {
+ // do relocation
+ policy_container::splice (policy_container::end (),
+ *this,
+ policy_container::s_iterator_to (*item));
+ }
+
+ inline void
+ erase (typename parent_trie::iterator item)
+ {
+ policy_container::erase (policy_container::s_iterator_to (*item));
+ }
+
+ inline void
+ clear ()
+ {
+ policy_container::clear ();
+ }
+
+ inline void
+ set_max_size (size_t max_size)
+ {
+ max_size_ = max_size;
+ }
+
+ inline size_t
+ get_max_size () const
+ {
+ return max_size_;
+ }
+
+ private:
+ type () : base_(*((Base*)0)) { };
+
+ private:
+ Base &base_;
+ size_t max_size_;
+ };
+ };
+};
+
+} // trie
+} // ndn
+
+#endif