/* Copyright 2003-2005 Joaquín M López Muñoz.

 * Distributed under the Boost Software License, Version 1.0.

 * (See accompanying file LICENSE_1_0.txt or copy at

 * http://www.boost.org/LICENSE_1_0.txt)

 *

 * See http://www.boost.org/libs/multi_index for library home page.

 */

#ifndef BOOST_MULTI_INDEX_DETAIL_BUCKET_ARRAY_HPP

#define BOOST_MULTI_INDEX_DETAIL_BUCKET_ARRAY_HPP

#if defined(_MSC_VER)&&(_MSC_VER>=1200)

#pragma once

#endif

#include <boost/config.hpp> /* keep it first to prevent nasty warns in MSVC */

#include <algorithm>

#include <boost/multi_index/detail/auto_space.hpp>

#include <boost/multi_index/detail/hash_index_node.hpp>

#include <boost/noncopyable.hpp>

#include <cstddef>

#include <limits.h>

#if !defined(BOOST_MULTI_INDEX_DISABLE_SERIALIZATION)

#include <boost/archive/archive_exception.hpp>

#include <boost/serialization/access.hpp>

#include <boost/throw_exception.hpp> 

#endif

namespace boost{

namespace multi_index{

namespace detail{

/* bucket structure for use by hashed indices */

class bucket_array_base:private noncopyable

{

protected:

  inline static std::size_t next_prime(std::size_t n)

  {

    static const std::size_t prime_list[]={

      53ul, 97ul, 193ul, 389ul, 769ul,

      1543ul, 3079ul, 6151ul, 12289ul, 24593ul,

      49157ul, 98317ul, 196613ul, 393241ul, 786433ul,

      1572869ul, 3145739ul, 6291469ul, 12582917ul, 25165843ul,

      50331653ul, 100663319ul, 201326611ul, 402653189ul, 805306457ul,

      1610612741ul, 3221225473ul,

#if ((((ULONG_MAX>>16)>>16)>>16)>>15)==0 /* unsigned long less than 64 bits */

      4294967291ul

#else

      /* obtained with aid from

       *   http://javaboutique.internet.com/prime_numb/

       *   http://www.rsok.com/~jrm/next_ten_primes.html

       * and verified with

       *   http://www.alpertron.com.ar/ECM.HTM

       */

      6442450939ul, 12884901893ul, 25769803751ul, 51539607551ul,

      103079215111ul, 206158430209ul, 412316860441ul, 824633720831ul,

      1649267441651ul, 3298534883309ul, 6597069766657ul, 13194139533299ul,

      26388279066623ul, 52776558133303ul, 105553116266489ul, 211106232532969ul,

      422212465066001ul, 844424930131963ul, 1688849860263953ul,

      3377699720527861ul, 6755399441055731ul, 13510798882111483ul,

      27021597764222939ul, 54043195528445957ul, 108086391056891903ul,

      216172782113783843ul, 432345564227567621ul, 864691128455135207ul,

      1729382256910270481ul, 3458764513820540933ul, 6917529027641081903ul,

      13835058055282163729ul, 18446744073709551557ul

#endif

    };

    static const std::size_t prime_list_size=

      sizeof(prime_list)/sizeof(prime_list[0]);

    std::size_t const *bound=

      std::lower_bound(prime_list,prime_list+prime_list_size,n);

    if(bound==prime_list+prime_list_size)bound--;

    return *bound;

  }

};

template<typename Allocator>

class bucket_array:public bucket_array_base

{

public:

  bucket_array(const Allocator& al,hashed_index_node_impl* end_,std::size_t size):

    size_(bucket_array_base::next_prime(size)),

    spc(al,size_+1)

  {

    clear();

    end()->next()=end_;

    end_->next()=end();

  }

  std::size_t size()const

  {

    return size_;

  }

  std::size_t position(std::size_t hash)const

  {

    return hash%size_;

  }

  hashed_index_node_impl* begin()const{return &buckets()[0];}

  hashed_index_node_impl* end()const{return &buckets()[size_];}

  hashed_index_node_impl* at(std::size_t n)const{return &buckets()[n];}

  std::size_t first_nonempty(std::size_t n)const

  {

    for(;;++n){

      hashed_index_node_impl* x=at(n);

      if(x->next()!=x)return n;

    }

  }

  void clear()

  {

    for(hashed_index_node_impl* x=begin(),*y=end();x!=y;++x)x->next()=x;

  }

  void swap(bucket_array& x)

  {

    std::swap(size_,x.size_);

    spc.swap(x.spc);

  }

private:

  std::size_t                                  size_;

  auto_space<hashed_index_node_impl,Allocator> spc;

  hashed_index_node_impl* buckets()const

  {

    return spc.data();

  }

#if !defined(BOOST_MULTI_INDEX_DISABLE_SERIALIZATION)

  friend class boost::serialization::access;

  /* bucket_arrays do not emit any kind of serialization info. They are

   * fed to Boost.Serialization as hashed index iterators need to track

   * them during serialization.

   */

  template<class Archive>

  void serialize(Archive&,const unsigned int)

  {

  }

#endif

};

template<typename Allocator>

void swap(bucket_array<Allocator>& x,bucket_array<Allocator>& y)

{

  x.swap(y);

}

} /* namespace multi_index::detail */

} /* namespace multi_index */

#if !defined(BOOST_MULTI_INDEX_DISABLE_SERIALIZATION)

/* bucket_arrays never get constructed directly by Boost.Serialization,

 * as archives are always fed pointers to previously existent

 * arrays. So, if this is called it means we are dealing with a

 * somehow invalid archive.

 */

#if defined(BOOST_NO_ARGUMENT_DEPENDENT_LOOKUP)

namespace serialization{

#else

namespace multi_index{

namespace detail{

#endif

template<class Archive,typename Allocator>

inline void load_construct_data(

  Archive&,boost::multi_index::detail::bucket_array<Allocator>*,

  const unsigned int)

{

  throw_exception(

    archive::archive_exception(archive::archive_exception::other_exception));

}

#if defined(BOOST_NO_ARGUMENT_DEPENDENT_LOOKUP)

} /* namespace serialization */

#else

} /* namespace multi_index::detail */

} /* namespace multi_index */

#endif

#endif

} /* namespace boost */

#endif