stream_slicer.hpp

Go to the documentation of this file.

/*
 * Copyright 2008,2009,2010,2011,2012 Stephan Ossowski, Korbinian Schneeberger,
 * Felix Ott, Joerg Hagmann, Alf Scotland, Sebastian Bender
 * 
 * This file is part of SHORE.
 * 
 * SHORE 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.
 * 
 * SHORE 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 SHORE.  If not, see <http://www.gnu.org/licenses/>.
 */


#ifndef SHORE_STREAM_STREAM_SLICER_HPP__
#define SHORE_STREAM_STREAM_SLICER_HPP__

#include <string>

#include "shore/base/memops.hpp"
#include "shore/stream/streams.hpp"

namespace shore {

class stream_slicer
{
 public:

        struct slice
        {
                const char *data;
                size_t size;
                uint64_t offset;

                bool eof;
        };

 private:

        slice m_slice;

        shore::istreams m_is;
        shore::mmapping m_mmapping;

        size_t m_blocksize;

        char *m_readbuf;

        bool m_mmapok;


        bool try_mmap(const std::string &fn);


        stream_slicer(const stream_slicer &other);
        stream_slicer &operator=(const stream_slicer &other);

 public:

        stream_slicer(const std::string &fn,const size_t bs,
                      const uint64_t startoff=0);

        stream_slicer(std::istream &is,const size_t bs,
                      const uint64_t startoff=0);

        ~stream_slicer();

        const slice &current() const;

        bool has_data() const;

        void move(const uint64_t n);
};

} // namespace

#endif // SHORE_STREAM_STREAM_SLICER_HPP__