Cursors refactoring part one

src/cursorcommon.h

@@ -0,0 +1,90 @@
+/*
+ * LMDB Abstraction Layer.
+ * Copyright (C) 2023  Yury Gubich <blue@macaw.me>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+
+#include <stdint.h>
+#include <string>
+
+#include <lmdb.h>
+
+namespace LMDBAL {
+
+class Transaction;
+class StorageCommon;
+
+class CursorCommon {
+    friend class Transaction;
+protected:
+    enum State {            /**<Cursor state:*/
+        closed,             /**<    - closed*/
+        openedPublic,       /**<    - opened with public transaction, all storages will be notified about it after it's done*/
+        openedPrivate       /**<    - opened with private transaction, only current storage will be notified when cursor is closed*/
+    };
+
+protected:
+    CursorCommon();
+    CursorCommon(StorageCommon* storage);
+    CursorCommon(const CursorCommon& other) = delete;
+    CursorCommon(CursorCommon&& other);
+    virtual ~CursorCommon() noexcept;
+
+    CursorCommon& operator = (const CursorCommon& other) = delete;
+    CursorCommon& operator = (CursorCommon&& other);
+
+public:
+    void open();
+    void open(const Transaction& transaction);
+    void renew();
+    void renew(const Transaction& transaction);
+    bool opened() const;
+    bool empty() const;
+    void close();
+
+protected:
+    void terminated();
+    void dropped();
+    void reset();
+
+protected:
+    uint32_t id;
+    State state;
+    MDB_cursor* handle;
+    StorageCommon* storage;
+
+private:
+    inline static const std::string openCursorMethodName = "Cursor::open";      /**<\brief member function name, just for exceptions*/
+    inline static const std::string closeCursorMethodName = "Cursor::close";    /**<\brief member function name, just for exceptions*/
+    inline static const std::string renewCursorMethodName = "Cursor::renew";    /**<\brief member function name, just for exceptions*/
+
+protected:
+    inline static const std::string firstMethodName = "first";                  /**<\brief member function name, just for exceptions in heir*/
+    inline static const std::string lastMethodName = "last";                    /**<\brief member function name, just for exceptions in heir*/
+    inline static const std::string nextMethodName = "next";                    /**<\brief member function name, just for exceptions in heir*/
+    inline static const std::string prevMethodName = "prev";                    /**<\brief member function name, just for exceptions in heir*/
+    inline static const std::string currentMethodName = "current";              /**<\brief member function name, just for exceptions in heir*/
+    inline static const std::string setMethodName = "set";                      /**<\brief member function name, just for exceptions in heir*/
+
+    inline static const std::string firstOperationName = "Cursor::first";       /**<\brief member function name, just for exceptions in heir*/
+    inline static const std::string lastOperationName = "Cursor::last";         /**<\brief member function name, just for exceptions in heir*/
+    inline static const std::string nextOperationName = "Cursor::next";         /**<\brief member function name, just for exceptions in heir*/
+    inline static const std::string prevOperationName = "Cursor::prev";         /**<\brief member function name, just for exceptions in heir*/
+    inline static const std::string currentOperationName = "Cursor::current";   /**<\brief member function name, just for exceptions in heir*/
+};
+
+}