databaseCursorInterface.hpp

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/*
 * Copyright (c) 2014 Patrick P. Frey
 *
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/.
 */
#ifndef _STRUS_DATABASE_CURSOR_INTERFACE_HPP_INCLUDED
#define _STRUS_DATABASE_CURSOR_INTERFACE_HPP_INCLUDED
#include <string>

namespace strus
{

class DatabaseCursorInterface
{
public:
        class Slice
        {
        public:
                Slice()
                        :m_ptr(0),m_size(0){}
                Slice( const char* ptr_, std::size_t size_)
                        :m_ptr(ptr_),m_size(size_){}
                Slice( const Slice& o)
                        :m_ptr(o.m_ptr),m_size(o.m_size){}

                const char* ptr() const         {return m_ptr;}
                std::size_t size() const        {return m_size;}

                std::string tostring() const    {return std::string(m_ptr,m_size);}
                operator std::string() const    {return std::string(m_ptr,m_size);}
                bool defined() const            {return m_ptr!=0;}

        private:
                const char* m_ptr;              
                std::size_t m_size;             
        };

public:
        virtual ~DatabaseCursorInterface(){}

        virtual Slice seekUpperBound(
                        const char* keystr,
                        std::size_t keysize,
                        std::size_t domainkeysize)=0;

        virtual Slice seekUpperBoundRestricted(
                        const char* keystr,
                        std::size_t keysize,
                        const char* upkey,
                        std::size_t upkeysize)=0;

        virtual Slice seekFirst(
                        const char* domainkey,
                        std::size_t domainkeysize)=0;

        virtual Slice seekLast(
                        const char* domainkey,
                        std::size_t domainkeysize)=0;

        virtual Slice seekNext()=0;

        virtual Slice seekPrev()=0;

        virtual Slice key() const=0;

        virtual Slice value() const=0;
};

}//namespace
#endif