index_generator.hpp

/*---------------------------------------------------------------------------*\
 *
 *  bitpit
 *
 *  Copyright (C) 2015-2021 OPTIMAD engineering Srl
 *
 *  -------------------------------------------------------------------------
 *  License
 *  This file is part of bitpit.
 *
 *  bitpit is free software: you can redistribute it and/or modify it
 *  under the terms of the GNU Lesser General Public License v3 (LGPL)
 *  as published by the Free Software Foundation.
 *
 *  bitpit 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 Lesser General Public
 *  License for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public License
 *  along with bitpit. If not, see <http://www.gnu.org/licenses/>.
 *
\*---------------------------------------------------------------------------*/
 
#ifndef __BITPIT_INDEX_GENERATOR_HPP__
#define __BITPIT_INDEX_GENERATOR_HPP__
 
#include <cassert>
#include <iostream>
#include <limits>
#include <set>
 
#include "bitpit_common.hpp"
#include "bitpit_containers.hpp"
 
namespace bitpit {
 
template<typename id_t = long>
class IndexGenerator {
 
static_assert(std::is_integral<id_t>::value, "Index has to be an integer!");
static_assert(std::numeric_limits<id_t>::is_signed, "Index has to be signed!");
 
public:
    typedef id_t id_type;
 
    BITPIT_PUBLIC_API static const id_type NULL_ID;
 
    IndexGenerator();
 
    id_type generate();
    bool isAssigned(id_type id);
    void setAssigned(id_type id);
    void trash(id_type id);
 
    id_type getLatest();
    id_type getHighest();
 
    void reset();
 
    void dump(std::ostream &stream) const;
    void restore(std::istream &stream);
 
private:
    id_type m_latest;
    id_type m_lowest;
    id_type m_highest;
    std::set<id_type> m_trash;
 
    void eraseFromTrash(id_type id);
 
    int getBinaryArchiveVersion() const;
 
};
 
#ifndef __BITPIT_COMMON_UTILS_SRC__
extern template class IndexGenerator<int>;
extern template class IndexGenerator<long>;
#endif
 
}
 
// Include the implementation
#include "index_generator.tpp"
 
#endif