1/* Copyright 2003-2023 Joaquin M Lopez Munoz.
2 * Distributed under the Boost Software License, Version 1.0.
3 * (See accompanying file LICENSE_1_0.txt or copy at
4 * http://www.boost.org/LICENSE_1_0.txt)
5 *
6 * See http://www.boost.org/libs/multi_index for library home page.
7 */
8
9#ifndef BOOST_MULTI_INDEX_DETAIL_BUCKET_ARRAY_HPP
10#define BOOST_MULTI_INDEX_DETAIL_BUCKET_ARRAY_HPP
11
12#if defined(_MSC_VER)
13#pragma once
14#endif
15
16#include <boost/config.hpp> /* keep it first to prevent nasty warns in MSVC */
17#include <algorithm>
18#include <boost/core/noncopyable.hpp>
19#include <boost/multi_index/detail/allocator_traits.hpp>
20#include <boost/multi_index/detail/auto_space.hpp>
21#include <boost/multi_index/detail/hash_index_node.hpp>
22#include <boost/preprocessor/repetition/repeat.hpp>
23#include <boost/preprocessor/seq/elem.hpp>
24#include <boost/preprocessor/seq/enum.hpp>
25#include <boost/preprocessor/seq/size.hpp>
26#include <cstddef>
27#include <limits.h>
28
29#if !defined(BOOST_MULTI_INDEX_DISABLE_SERIALIZATION)
30#include <boost/core/serialization.hpp>
31#include <boost/multi_index/detail/bad_archive_exception.hpp>
32#include <boost/throw_exception.hpp>
33#endif
34
35namespace boost{
36
37namespace multi_index{
38
39namespace detail{
40
41/* bucket structure for use by hashed indices */
42
43#define BOOST_MULTI_INDEX_BA_SIZES_32BIT \
44(53ul)(97ul)(193ul)(389ul)(769ul) \
45(1543ul)(3079ul)(6151ul)(12289ul)(24593ul) \
46(49157ul)(98317ul)(196613ul)(393241ul)(786433ul) \
47(1572869ul)(3145739ul)(6291469ul)(12582917ul)(25165843ul) \
48(50331653ul)(100663319ul)(201326611ul)(402653189ul)(805306457ul) \
49(1610612741ul)(3221225473ul)
50
51#if ((((ULONG_MAX>>16)>>16)>>16)>>15)==0 /* unsigned long less than 64 bits */
52#define BOOST_MULTI_INDEX_BA_SIZES \
53BOOST_MULTI_INDEX_BA_SIZES_32BIT \
54(4294967291ul)
55#else
56 /* obtained with aid from
57 * http://javaboutique.internet.com/prime_numb/
58 * http://www.rsok.com/~jrm/next_ten_primes.html
59 * and verified with
60 * http://www.alpertron.com.ar/ECM.HTM
61 */
62
63#define BOOST_MULTI_INDEX_BA_SIZES \
64BOOST_MULTI_INDEX_BA_SIZES_32BIT \
65(6442450939ul)(12884901893ul)(25769803751ul)(51539607551ul) \
66(103079215111ul)(206158430209ul)(412316860441ul)(824633720831ul) \
67(1649267441651ul)(3298534883309ul)(6597069766657ul)(13194139533299ul) \
68(26388279066623ul)(52776558133303ul)(105553116266489ul)(211106232532969ul) \
69(422212465066001ul)(844424930131963ul)(1688849860263953ul) \
70(3377699720527861ul)(6755399441055731ul)(13510798882111483ul) \
71(27021597764222939ul)(54043195528445957ul)(108086391056891903ul) \
72(216172782113783843ul)(432345564227567621ul)(864691128455135207ul) \
73(1729382256910270481ul)(3458764513820540933ul)(6917529027641081903ul) \
74(13835058055282163729ul)(18446744073709551557ul)
75#endif
76
77template<bool _=true> /* templatized to have in-header static var defs */
78class bucket_array_base:private noncopyable
79{
80protected:
81 static const std::size_t sizes[
82 BOOST_PP_SEQ_SIZE(BOOST_MULTI_INDEX_BA_SIZES)];
83
84 static std::size_t size_index(std::size_t n)
85 {
86 const std::size_t *bound=std::lower_bound(sizes,sizes+sizes_length,n);
87 if(bound==sizes+sizes_length)--bound;
88 return bound-sizes;
89 }
90
91#define BOOST_MULTI_INDEX_BA_POSITION_CASE(z,n,_) \
92 case n:return hash%BOOST_PP_SEQ_ELEM(n,BOOST_MULTI_INDEX_BA_SIZES);
93
94 static std::size_t position(std::size_t hash,std::size_t size_index_)
95 {
96 /* Accelerate hash%sizes[size_index_] by replacing with a switch on
97 * hash%Ci expressions, each Ci a compile-time constant, which the
98 * compiler can implement without using integer division.
99 */
100
101 switch(size_index_){
102 default: /* never used */
103 BOOST_PP_REPEAT(
104 BOOST_PP_SEQ_SIZE(BOOST_MULTI_INDEX_BA_SIZES),
105 BOOST_MULTI_INDEX_BA_POSITION_CASE,~)
106 }
107 }
108
109private:
110 static const std::size_t sizes_length;
111};
112
113template<bool _>
114const std::size_t bucket_array_base<_>::sizes[]={
115 BOOST_PP_SEQ_ENUM(BOOST_MULTI_INDEX_BA_SIZES)
116};
117
118template<bool _>
119const std::size_t bucket_array_base<_>::sizes_length=
120 sizeof(bucket_array_base<_>::sizes)/
121 sizeof(bucket_array_base<_>::sizes[0]);
122
123#undef BOOST_MULTI_INDEX_BA_POSITION_CASE
124#undef BOOST_MULTI_INDEX_BA_SIZES
125#undef BOOST_MULTI_INDEX_BA_SIZES_32BIT
126
127template<typename Allocator>
128class bucket_array:bucket_array_base<>
129{
130 typedef bucket_array_base<> super;
131 typedef hashed_index_base_node_impl<
132 typename rebind_alloc_for<
133 Allocator,
134 char
135 >::type
136 > base_node_impl_type;
137
138public:
139 typedef typename base_node_impl_type::base_pointer base_pointer;
140 typedef typename base_node_impl_type::pointer pointer;
141
142 bucket_array(const Allocator& al,pointer end_,std::size_t size_):
143 size_index_(super::size_index(n: size_)),
144 spc(al,static_cast<auto_space_size_type>(super::sizes[size_index_]+1))
145 {
146 clear(end_);
147 }
148
149 std::size_t size()const
150 {
151 return super::sizes[size_index_];
152 }
153
154 std::size_t position(std::size_t hash)const
155 {
156 return super::position(hash,size_index_);
157 }
158
159 base_pointer begin()const{return buckets();}
160 base_pointer end()const{return buckets()+size();}
161 base_pointer at(std::size_t n)const{return buckets()+n;}
162
163 void clear(pointer end_)
164 {
165 for(base_pointer x=begin(),y=end();x!=y;++x)x->prior()=pointer(0);
166 end()->prior()=end_->prior()=end_;
167 end_->next()=end();
168 }
169
170 void swap(bucket_array& x)
171 {
172 std::swap(size_index_,x.size_index_);
173 spc.swap(x.spc);
174 }
175
176 template<typename BoolConstant>
177 void swap(bucket_array& x,BoolConstant swap_allocators)
178 {
179 std::swap(size_index_,x.size_index_);
180 spc.swap(x.spc,swap_allocators);
181 }
182
183private:
184 typedef auto_space<base_node_impl_type,Allocator> auto_space_type;
185 typedef typename auto_space_type::size_type auto_space_size_type;
186
187 std::size_t size_index_;
188 auto_space_type spc;
189
190 base_pointer buckets()const
191 {
192 return spc.data();
193 }
194
195#if !defined(BOOST_MULTI_INDEX_DISABLE_SERIALIZATION)
196 friend class boost::serialization::access;
197
198 /* bucket_arrays do not emit any kind of serialization info. They are
199 * fed to Boost.Serialization as hashed index iterators need to track
200 * them during serialization.
201 */
202
203 template<class Archive>
204 void serialize(Archive&,const unsigned int)
205 {
206 }
207#endif
208};
209
210template<typename Allocator>
211void swap(bucket_array<Allocator>& x,bucket_array<Allocator>& y)
212{
213 x.swap(y);
214}
215
216} /* namespace multi_index::detail */
217
218} /* namespace multi_index */
219
220#if !defined(BOOST_MULTI_INDEX_DISABLE_SERIALIZATION)
221/* bucket_arrays never get constructed directly by Boost.Serialization,
222 * as archives are always fed pointers to previously existent
223 * arrays. So, if this is called it means we are dealing with a
224 * somehow invalid archive.
225 */
226
227#if defined(BOOST_NO_ARGUMENT_DEPENDENT_LOOKUP)
228namespace serialization{
229#else
230namespace multi_index{
231namespace detail{
232#endif
233
234template<class Archive,typename Allocator>
235inline void load_construct_data(
236 Archive&,boost::multi_index::detail::bucket_array<Allocator>*,
237 const unsigned int)
238{
239 throw_exception(e: bad_archive_exception());
240}
241
242#if defined(BOOST_NO_ARGUMENT_DEPENDENT_LOOKUP)
243} /* namespace serialization */
244#else
245} /* namespace multi_index::detail */
246} /* namespace multi_index */
247#endif
248
249#endif
250
251} /* namespace boost */
252
253#endif
254