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diff --git a/binaryurp/source/cache.hxx b/binaryurp/source/cache.hxx
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+/*************************************************************************
+*
+* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+*
+* Copyright 2000, 2011 Oracle and/or its affiliates.
+*
+* OpenOffice.org - a multi-platform office productivity suite
+*
+* This file is part of OpenOffice.org.
+*
+* OpenOffice.org is free software: you can redistribute it and/or modify
+* it under the terms of the GNU Lesser General Public License version 3
+* only, as published by the Free Software Foundation.
+*
+* OpenOffice.org is distributed in the hope that it will be useful,
+* but WITHOUT ANY WARRANTY; without even the implied warranty of
+* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+* GNU Lesser General Public License version 3 for more details
+* (a copy is included in the LICENSE file that accompanied this code).
+*
+* You should have received a copy of the GNU Lesser General Public License
+* version 3 along with OpenOffice.org.  If not, see
+* <http://www.openoffice.org/license.html>
+* for a copy of the LGPLv3 License.
+*
+************************************************************************/
+
+#ifndef INCLUDED_BINARYURP_SOURCE_CACHE_HXX
+#define INCLUDED_BINARYURP_SOURCE_CACHE_HXX
+
+#include "sal/config.h"
+
+#include <cstddef>
+#include <map>
+
+#include "boost/noncopyable.hpp"
+#include "osl/diagnose.h"
+#include "sal/types.h"
+
+namespace binaryurp {
+
+namespace cache {
+
+enum { size = 256, ignore = 0xFFFF };
+
+}
+
+template< typename T > class Cache: private boost::noncopyable {
+public:
+    explicit Cache(std::size_t size):
+        size_(size), first_(map_.end()), last_(map_.end())
+    {
+        OSL_ASSERT(size < cache::ignore);
+    }
+
+    sal_uInt16 add(T const & content, bool * found) {
+        OSL_ASSERT(found != 0);
+        typename Map::iterator i(map_.find(content));
+        *found = i != map_.end();
+        if (i == map_.end()) {
+            typename Map::size_type n = map_.size();
+            if (n < size_) {
+                i =
+                    (map_.insert(
+                        typename Map::value_type(
+                            content,
+                            Entry(
+                                static_cast< sal_uInt16 >(n), map_.end(),
+                                first_)))).
+                    first;
+                if (first_ == map_.end()) {
+                    last_ = i;
+                } else {
+                    first_->second.prev = i;
+                }
+                first_ = i;
+            } else if (last_ != map_.end()) {
+                i =
+                    (map_.insert(
+                        typename Map::value_type(
+                            content,
+                            Entry(last_->second.index, map_.end(), first_)))).
+                    first;
+                first_->second.prev = i;
+                first_ = i;
+                typename Map::iterator j(last_);
+                last_ = last_->second.prev;
+                last_->second.next = map_.end();
+                map_.erase(j);
+            } else {
+                // Reached iff size_ == 0:
+                return cache::ignore;
+            }
+        } else if (i != first_) {
+            // Move to front (reached only if size_ > 1):
+            i->second.prev->second.next = i->second.next;
+            if (i->second.next == map_.end()) {
+                last_ = i->second.prev;
+            } else {
+                i->second.next->second.prev = i->second.prev;
+            }
+            i->second.prev = map_.end();
+            i->second.next = first_;
+            first_->second.prev = i;
+            first_ = i;
+        }
+        return i->second.index;
+    }
+
+private:
+    struct Entry;
+
+    typedef std::map< T, Entry > Map;
+
+    struct Entry {
+        sal_uInt16 index;
+        typename Map::iterator prev;
+        typename Map::iterator next;
+
+        Entry(
+            sal_uInt16 theIndex, typename Map::iterator thePrev,
+            typename Map::iterator theNext):
+            index(theIndex), prev(thePrev), next(theNext) {}
+    };
+
+    std::size_t size_;
+    Map map_;
+    typename Map::iterator first_;
+    typename Map::iterator last_;
+};
+
+}
+
+#endif