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+/*
+ * 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.
+ */
+
+/**
+ * \file RecordTail.h
+ *
+ * List of journal record structs:
+ *   struct DequeueHeader
+ *   struct EnqueueHeader
+ *   struct EventHeader
+ *   struct FileHeader
+ *   struct RecordHeader
+ *   struct RecordTail         <-- This file
+ *   struct TransactionHeader
+ *
+ * Overview of journal record structs:
+ *
+ * <pre>
+ *  +------------+           +--------------+
+ *  | RecordTail |           | RecordHeader |
+ *  +------------+           |  (abstract)  |
+ *                           +--------------+
+ *                                   ^
+ *                                   |
+ *        +----------------+---------+-------+-------------------+
+ *        |                |                 |                   |
+ *  +------------+  +-------------+  +---------------+  +-------------------+
+ *  | FileHeader |  | EventHeader |  | DequeueHeader |  | TransactionHeader |
+ *  +------------+  +-------------+  +---------------+  +-------------------+
+ *                         ^
+ *                         |
+ *                 +---------------+
+ *                 | EnqueueHeader |
+ *                 +---------------+
+ *  </pre>
+ */
+
+#ifndef qpid_asyncStore_jrnl2_RecordTail_h_
+#define qpid_asyncStore_jrnl2_RecordTail_h_
+
+#include <stdint.h> // uint32_t, uint64_t
+
+namespace qpid {
+namespace asyncStore {
+namespace jrnl2 {
+
+class RecordHeader;
+
+#pragma pack(1)
+
+/**
+ * \brief Struct for the tail of all records which contain data and which must follow
+ * the data portion of that record.
+ *
+ * The magic number used here is the binary inverse (1's complement) of the magic
+ * used in the record header; this minimizes possible confusion with other headers
+ * that may be present during recovery. The tail is used with all records that have
+ * either XIDs or data - i.e. any size-variable content. Currently the only records
+ * that do NOT use the tail are non-transactional dequeues and filler records.
+ *
+ * Record layout in binary format (16 bytes):
+ * <pre>
+ *        0x0                                       0x7
+ *      +-----+-----+-----+-----+-----+-----+-----+-----+
+ * 0x00 |       m_xMagic        |       m_checkSum      |
+ *      +-----+-----+-----+-----+-----+-----+-----+-----+
+ * 0x08 |                  m_recordId                   |
+ *      +-----+-----+-----+-----+-----+-----+-----+-----+
+ * </pre>
+ */
+class RecordTail
+{
+public:
+    uint32_t m_xMagic;              ///< Binary inverse (1's complement) of hdr magic number
+    uint32_t m_checkSum;            ///< Checksum for header and body of record
+    uint64_t m_recordId;            ///< Record identifier matching that of the header for this record
+
+    /**
+     * \brief Default constructor, which sets most values to 0.
+     */
+    RecordTail();
+
+    /**
+     * \brief Convenience constructor which initializes values during construction.
+     *
+     * \param xMagic The inverse of the record header magic (ie ~rh._magic).
+     * \param checkSum The checksum for this record header and body.
+     * \param recordId The record identifier matching the record header.
+     */
+    RecordTail(const uint32_t xMagic,
+               const uint32_t checkSum,
+               const uint64_t recordId);
+
+    /**
+     * \brief Convenience constructor which initializes values during construction from existing RecordHeader
+     * instance.
+     *
+     * \param rh Header instance for which the RecordTail is to be created.
+     */
+    RecordTail(const RecordHeader& rh);
+
+    /**
+     * \brief Copy constructor.
+     *
+     * \param rt Instance to be copied.
+     */
+    RecordTail(const RecordTail& rt);
+
+    /**
+     * \brief Convenience copy method.
+     *
+     * \param rt Instance to be copied.
+     */
+    void copy(const RecordTail& rt);
+
+    /**
+     * \brief Resets all fields to default values (mostly 0).
+     */
+    void reset();
+
+    /**
+    * \brief Returns the size of the header in bytes.
+    */
+    static uint64_t getSize();
+
+};
+
+#pragma pack()
+
+}}} // namespace qpid::asyncStore::jrnl2
+
+#endif // qpid_asyncStore_jrnl2_RecordTail_h_