ceph/src/boost/boost/beast/core/detail/buffers_range_adaptor.hpp

   1 //
   2 // Copyright (c) 2016-2019 Vinnie Falco (vinnie dot falco at gmail dot com)
   3 //
   4 // Distributed under the Boost Software License, Version 1.0. (See accompanying
   5 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   6 //
   7 // Official repository: https://github.com/boostorg/beast
   8 //
   9
  10 #ifndef BOOST_BEAST_DETAIL_BUFFERS_RANGE_ADAPTOR_HPP
  11 #define BOOST_BEAST_DETAIL_BUFFERS_RANGE_ADAPTOR_HPP
  12
  13 #include <boost/beast/core/buffer_traits.hpp>
  14 #include <iterator>
  15 #include <type_traits>
  16
  17 namespace boost {
  18 namespace beast {
  19 namespace detail {
  20
  21 template<class BufferSequence>
  22 class buffers_range_adaptor
  23 {
  24     BufferSequence b_;
  25
  26 public:
  27 #if BOOST_BEAST_DOXYGEN
  28     using value_type = __see_below__;
  29 #else
  30     using value_type = buffers_type<BufferSequence>;
  31 #endif
  32
  33     class const_iterator
  34     {
  35         friend class buffers_range_adaptor;
  36
  37         using iter_type =
  38             buffers_iterator_type<BufferSequence>;
  39
  40         iter_type it_{};
  41
  42         const_iterator(iter_type const& it)
  43             : it_(it)
  44         {
  45         }
  46
  47     public:
  48         using value_type = typename
  49             buffers_range_adaptor::value_type;
  50         using pointer = value_type const*;
  51         using reference = value_type;
  52         using difference_type = std::ptrdiff_t;
  53         using iterator_category =
  54             std::bidirectional_iterator_tag;
  55
  56         const_iterator() = default;
  57
  58         bool
  59         operator==(const_iterator const& other) const
  60         {
  61             return it_ == other.it_;
  62         }
  63
  64         bool
  65         operator!=(const_iterator const& other) const
  66         {
  67             return !(*this == other);
  68         }
  69
  70         reference
  71         operator*() const
  72         {
  73             return *it_;
  74         }
  75
  76         pointer
  77         operator->() const = delete;
  78
  79         const_iterator&
  80         operator++()
  81         {
  82             ++it_;
  83             return *this;
  84         }
  85
  86         const_iterator
  87         operator++(int)
  88         {
  89             auto temp = *this;
  90             ++(*this);
  91             return temp;
  92         }
  93
  94         const_iterator&
  95         operator--()
  96         {
  97             --it_;
  98             return *this;
  99         }
 100
 101         const_iterator
 102         operator--(int)
 103         {
 104             auto temp = *this;
 105             --(*this);
 106             return temp;
 107         }
 108     };
 109
 110     explicit
 111     buffers_range_adaptor(BufferSequence const& b)
 112         : b_(b)
 113     {
 114     }
 115
 116     const_iterator
 117     begin() const noexcept
 118     {
 119         return {net::buffer_sequence_begin(b_)};
 120     }
 121
 122     const_iterator
 123     end() const noexcept
 124     {
 125         return {net::buffer_sequence_end(b_)};
 126     }
 127 };
 128
 129 } // detail
 130 } // beast
 131 } // boost
 132
 133 #endif