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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
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#ifndef BERKELEYDBPROXY_DB_HXX_
#define BERKELEYDBPROXY_DB_HXX_

#ifdef SYSTEM_DB
#include <db.h>
#else
#include <berkeleydb/db.h>
#endif

#include "com/sun/star/ucb/XSimpleFileAccess.hpp"

#include <hash_map>
#include <rtl/string.hxx>

extern "C" { 
  typedef void *(*db_malloc_fcn_type)(size_t); 
  typedef void *(*db_realloc_fcn_type)(void *, size_t); 
  typedef void (*db_free_fcn_type)(void *); 
}


namespace berkeleydbproxy {

    class Dbc;
    class Dbt;

    namespace db_internal
    {
        class Noncopyable
        {
            // not implemented
            Noncopyable(const Noncopyable&);
            void operator=(const Noncopyable&);
        protected:
            Noncopyable() {}
            ~Noncopyable() {}
        };
    }
    
    class DbException 
    {
        rtl::OString what_;
    public:
        explicit DbException(rtl::OString const & whatparam) 
        : what_(whatparam)
        {}
        
	    const char *what() const
        { return what_.getStr(); }
    };
  
	struct eq
	{
		bool operator()( const rtl::OString& rKey1, const rtl::OString& rKey2 ) const
			{ return rKey1.compareTo( rKey2 ) == 0; }
	};

	struct ha
	{
		size_t operator()( const rtl::OString& rName ) const
			{ return rName.hashCode(); }
	};


//#define TEST_DBHELP

	class DBData
	{
		friend class		DBHelp;

		int					m_nSize;
		char*				m_pBuffer;

		void copyToBuffer( const char* pSrcData, int nSize );

	public:
		DBData( void )
			: m_nSize( 0 )
			, m_pBuffer( NULL )
		{}
		~DBData()
			{ delete [] m_pBuffer; }

  	    int getSize() const
			{ return m_nSize; }
  	    const char* getData() const
			{ return m_pBuffer; }
	};

	typedef std::hash_map< rtl::OString,std::pair<int,int>,ha,eq >	StringToValPosMap;
	typedef std::hash_map< rtl::OString,rtl::OString,ha,eq >		StringToDataMap;

	class DBHelp
	{
		rtl::OUString		m_aFileURL;
		StringToDataMap*	m_pStringToDataMap;
		StringToValPosMap*	m_pStringToValPosMap;
		com::sun::star::uno::Reference< com::sun::star::ucb::XSimpleFileAccess >
							m_xSFA;

		com::sun::star::uno::Sequence< sal_Int8 >
							m_aItData;
		const char*			m_pItData;
		int					m_nItRead;
		int					m_iItPos;

		bool implReadLenAndData( const char* pData, int& riPos, DBData& rValue );

	public:
        //DBHelp must get a fileURL which can then directly be used by simple file access.
        //SimpleFileAccess requires file URLs as arguments. Passing file path may work but fails
        //for example when using long file paths on Windows, which start with "\\?\"
		DBHelp( const rtl::OUString& rFileURL,
			com::sun::star::uno::Reference< com::sun::star::ucb::XSimpleFileAccess > xSFA )
				: m_aFileURL( rFileURL )
				, m_pStringToDataMap( NULL )
				, m_pStringToValPosMap( NULL )
				, m_xSFA( xSFA )
				, m_pItData( NULL )
				, m_nItRead( -1 )
				, m_iItPos( -1 )
		{
            OSL_ASSERT(!rFileURL.compareTo(rtl::OUString(RTL_CONSTASCII_USTRINGPARAM("file:")), 5));
        }
		~DBHelp()
			{ releaseHashMap(); }

		void createHashMap( bool bOptimizeForPerformance = false );
		void releaseHashMap( void );

#ifdef TEST_DBHELP
		bool testAgainstDb( const rtl::OUString& fileURL, bool bOldDbAccess );
#endif

		bool getValueForKey( const rtl::OString& rKey, DBData& rValue );

		bool startIteration( void );
		bool getNextKeyAndValue( DBData& rKey, DBData& rValue );
		void stopIteration( void );
	};

    class Db : db_internal::Noncopyable 
    {	
    private:	
	    DB* m_pDBP;
	    DBHelp* m_pDBHelp;
	
    public:
	    Db();
	    ~Db();

	    void setDBHelp( DBHelp* pDBHelp )
			{ m_pDBHelp = pDBHelp; }
	    DBHelp* getDBHelp( void )
			{ return m_pDBHelp; }

	    int close(u_int32_t flags);

	    int open(DB_TXN *txnid,
			     const char *file,
			     const char *database, 
			     DBTYPE type, 
			     u_int32_t flags, 
			     int mode);

        int open(DB_TXN *txnid,
			     ::rtl::OUString const & fileURL,
			     DBTYPE type, 
			     u_int32_t flags, 
			     int mode);

	
    	int get(DB_TXN* txnid, Dbt *key, Dbt *data, u_int32_t flags);
	
	    int cursor(DB_TXN *txnid, Dbc **cursorp, u_int32_t flags);
    };
  
    class Dbc : db_internal::Noncopyable 
    {	
    	friend class Db;
	    friend class Dbt;

    private:	
	    DBC* m_pDBC;
	
	    explicit Dbc(DBC* pDBC);
	    ~Dbc();
	
    public:
	    int close();
	
	    int get(Dbt *key, Dbt *data, u_int32_t flags);
    };
  
    class Dbt: private DBT 
    {	
	    friend class Db;
	    friend class Dbc;
	
    public:
	    Dbt(void *data_arg, u_int32_t size_arg); 
	
	    Dbt(); 
        //Dbt(const Dbt & other);
        //Dbt & operator=(const Dbt & other);
	
	    ~Dbt();

  	    void *get_data() const;
	    void set_data(void *value);
	
  	    u_int32_t get_size() const;
	    void set_size(u_int32_t value);

	    void set_flags(u_int32_t);
    };
}

#endif