1 files changed, 100 insertions, 0 deletions
diff --git a/qpid/cpp/src/qpid/broker/PagedQueue.h b/qpid/cpp/src/qpid/broker/PagedQueue.h
new file mode 100644
index 0000000000..c8a9f13fc7
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+++ b/qpid/cpp/src/qpid/broker/PagedQueue.h
@@ -0,0 +1,100 @@
+#ifndef QPID_BROKER_PAGEDQUEUE_H
+#define QPID_BROKER_PAGEDQUEUE_H
+
+/*
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ *
+ */
+#include "qpid/broker/Messages.h"
+#include "qpid/broker/Message.h"
+#include "qpid/framing/SequenceSet.h"
+#include "qpid/sys/MemoryMappedFile.h"
+#include <deque>
+#include <list>
+#include <map>
+
+namespace qpid {
+namespace broker {
+class ProtocolRegistry;
+/**
+ *
+ */
+class PagedQueue : public Messages {
+  public:
+    PagedQueue(const std::string& name, const std::string& directory, uint maxLoaded, uint pageFactor, ProtocolRegistry& protocols);
+    ~PagedQueue();
+    size_t size();
+    bool deleted(const QueueCursor&);
+    void publish(const Message& added);
+    Message* next(QueueCursor& cursor);
+    Message* release(const QueueCursor& cursor);
+    Message* find(const framing::SequenceNumber&, QueueCursor*);
+    Message* find(const QueueCursor&);
+    void foreach(Functor);
+  private:
+    class Page {
+      public:
+        Page(size_t size, size_t offset);
+        void read();//decode messages from memory mapped file
+        void write();//encode messages into memory mapped file
+        bool isLoaded() const;
+        bool empty() const;
+        void deleted(qpid::framing::SequenceNumber);
+        Message* release(qpid::framing::SequenceNumber);
+        bool add(const Message&);
+        Message* next(uint32_t version, QueueCursor&);
+        Message* find(qpid::framing::SequenceNumber);
+        void load(qpid::sys::MemoryMappedFile&,ProtocolRegistry&);
+        void unload(qpid::sys::MemoryMappedFile&);
+        void clear(qpid::sys::MemoryMappedFile&);
+        size_t available() const;
+      private:
+        size_t size;
+        size_t offset;
+
+        char* region;//0 implies not mapped
+        qpid::framing::SequenceSet contents;
+        qpid::framing::SequenceSet acquired;
+        std::deque<Message> messages;//decoded representation
+        size_t used;//amount of data used to encode current set of messages held
+    };
+
+    qpid::sys::MemoryMappedFile file;
+    std::string name;
+    const size_t pageSize;
+    const uint maxLoaded;
+    ProtocolRegistry& protocols;
+    size_t offset;
+    typedef std::map<qpid::framing::SequenceNumber, Page> Used;
+    Used used;
+    std::list<Page> free;
+    uint loaded;
+    uint32_t version;
+
+    void addPages(size_t count);
+    Page& newPage(qpid::framing::SequenceNumber);
+    Used::iterator findPage(const QueueCursor& cursor);
+    Used::iterator findPage(qpid::framing::SequenceNumber n, bool loadIfRequired);
+    void load(Page&);
+    void unload(Page&);
+    bool deleted(qpid::framing::SequenceNumber);
+};
+}} // namespace qpid::broker
+
+#endif  /*!QPID_BROKER_PAGEDQUEUE_H*/