ceph/src/boost/libs/container/include/boost/container/detail/block_slist.hpp

   1 //////////////////////////////////////////////////////////////////////////////
   2 //
   3 // (C) Copyright Ion Gaztanaga 2015-2015. Distributed under the Boost
   4 // Software License, Version 1.0. (See accompanying file
   5 // LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   6 //
   7 // See http://www.boost.org/libs/container for documentation.
   8 //
   9 //////////////////////////////////////////////////////////////////////////////
  10
  11 #ifndef BOOST_CONTAINER_DETAIL_BLOCK_SLIST_HEADER
  12 #define BOOST_CONTAINER_DETAIL_BLOCK_SLIST_HEADER
  13
  14 #ifndef BOOST_CONFIG_HPP
  15 #  include <boost/config.hpp>
  16 #endif
  17
  18 #if defined(BOOST_HAS_PRAGMA_ONCE)
  19 #  pragma once
  20 #endif
  21
  22
  23 #include <boost/container/detail/config_begin.hpp>
  24 #include <boost/container/detail/workaround.hpp>
  25 #include <boost/container/container_fwd.hpp>
  26 #include <boost/container/pmr/memory_resource.hpp>
  27 #include <boost/container/throw_exception.hpp>
  28
  29 #include <boost/move/detail/type_traits.hpp>
  30 #include <boost/intrusive/linear_slist_algorithms.hpp>
  31 #include <boost/assert.hpp>
  32
  33 #include <cstddef>
  34
  35 namespace boost {
  36 namespace container {
  37 namespace pmr {
  38
  39 struct slist_node
  40 {
  41    slist_node *next;
  42 };
  43
  44 struct slist_node_traits
  45 {
  46    typedef slist_node         node;
  47    typedef slist_node*        node_ptr;
  48    typedef const slist_node*  const_node_ptr;
  49
  50    static node_ptr get_next(const_node_ptr n)
  51    {  return n->next;  }
  52
  53    static void set_next(const node_ptr & n, const node_ptr & next)
  54    {  n->next = next;  }
  55 };
  56
  57 struct block_slist_header
  58    : public slist_node
  59 {
  60    std::size_t size;
  61 };
  62
  63 typedef bi::linear_slist_algorithms<slist_node_traits> slist_algo;
  64
  65 template<class DerivedFromBlockSlistHeader = block_slist_header>
  66 class block_slist_base
  67 {
  68    slist_node m_slist;
  69
  70    static const std::size_t MaxAlignMinus1 = memory_resource::max_align-1u;
  71
  72    public:
  73
  74    static const std::size_t header_size = std::size_t(sizeof(DerivedFromBlockSlistHeader) + MaxAlignMinus1) & std::size_t(~MaxAlignMinus1);
  75
  76    explicit block_slist_base()
  77    {  slist_algo::init_header(&m_slist);  }
  78
  79    #if !defined(BOOST_NO_CXX11_DELETED_FUNCTIONS) || defined(BOOST_CONTAINER_DOXYGEN_INVOKED)
  80    block_slist_base(const block_slist_base&) = delete;
  81    block_slist_base operator=(const block_slist_base&) = delete;
  82    #else
  83    private:
  84    block_slist_base          (const block_slist_base&);
  85    block_slist_base operator=(const block_slist_base&);
  86    public:
  87    #endif
  88
  89    ~block_slist_base()
  90    {}
  91
  92    void *allocate(std::size_t size, memory_resource &mr)
  93    {
  94       if((size_t(-1) - header_size) < size)
  95          throw_bad_alloc();
  96       void *p = mr.allocate(size+header_size);
  97       block_slist_header &mb  = *::new((void*)p) DerivedFromBlockSlistHeader;
  98       mb.size = size+header_size;
  99       slist_algo::link_after(&m_slist, &mb);
 100       return (char *)p + header_size;
 101    }
 102
 103    void release(memory_resource &mr) BOOST_NOEXCEPT
 104    {
 105       slist_node *n = slist_algo::node_traits::get_next(&m_slist);
 106       while(n){
 107          DerivedFromBlockSlistHeader &d = static_cast<DerivedFromBlockSlistHeader&>(*n);
 108          n = slist_algo::node_traits::get_next(n);
 109          std::size_t size = d.block_slist_header::size;
 110          d.~DerivedFromBlockSlistHeader();
 111          mr.deallocate(reinterpret_cast<char*>(&d), size, memory_resource::max_align);
 112       }
 113       slist_algo::init_header(&m_slist);
 114    }
 115 };
 116
 117 class block_slist
 118    : public block_slist_base<>
 119 {
 120    memory_resource &m_upstream_rsrc;
 121
 122    public:
 123
 124    explicit block_slist(memory_resource &upstream_rsrc)
 125       : block_slist_base<>(), m_upstream_rsrc(upstream_rsrc)
 126    {}
 127
 128    #if !defined(BOOST_NO_CXX11_DELETED_FUNCTIONS) || defined(BOOST_CONTAINER_DOXYGEN_INVOKED)
 129    block_slist(const block_slist&) = delete;
 130    block_slist operator=(const block_slist&) = delete;
 131    #else
 132    private:
 133    block_slist          (const block_slist&);
 134    block_slist operator=(const block_slist&);
 135    public:
 136    #endif
 137
 138    ~block_slist()
 139    {  this->release();  }
 140
 141    void *allocate(std::size_t size)
 142    {  return this->block_slist_base<>::allocate(size, m_upstream_rsrc);  }
 143
 144    void release() BOOST_NOEXCEPT
 145    {  return this->block_slist_base<>::release(m_upstream_rsrc);  }
 146
 147    memory_resource& upstream_resource() const BOOST_NOEXCEPT
 148    {  return m_upstream_rsrc;   }
 149 };
 150
 151 }  //namespace pmr {
 152 }  //namespace container {
 153 }  //namespace boost {
 154
 155 #include <boost/container/detail/config_end.hpp>
 156
 157 #endif   //BOOST_CONTAINER_DETAIL_BLOCK_SLIST_HEADER