ceph/src/boost/boost/beast/core/detail/buffer.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_CORE_DETAIL_BUFFER_HPP
  11 #define BOOST_BEAST_CORE_DETAIL_BUFFER_HPP
  12
  13 #include <boost/beast/core/error.hpp>
  14 #include <boost/asio/buffer.hpp>
  15 #include <boost/optional.hpp>
  16 #include <stdexcept>
  17
  18 namespace boost {
  19 namespace beast {
  20 namespace detail {
  21
  22 template<
  23     class DynamicBuffer,
  24     class ErrorValue>
  25 auto
  26 dynamic_buffer_prepare_noexcept(
  27     DynamicBuffer& buffer,
  28     std::size_t size,
  29     error_code& ec,
  30     ErrorValue ev) ->
  31         boost::optional<typename
  32         DynamicBuffer::mutable_buffers_type>
  33 {
  34     if(buffer.max_size() - buffer.size() < size)
  35     {
  36         // length error
  37         ec = ev;
  38         return boost::none;
  39     }
  40     boost::optional<typename
  41         DynamicBuffer::mutable_buffers_type> result;
  42     result.emplace(buffer.prepare(size));
  43     ec = {};
  44     return result;
  45 }
  46
  47 template<
  48     class DynamicBuffer,
  49     class ErrorValue>
  50 auto
  51 dynamic_buffer_prepare(
  52     DynamicBuffer& buffer,
  53     std::size_t size,
  54     error_code& ec,
  55     ErrorValue ev) ->
  56         boost::optional<typename
  57         DynamicBuffer::mutable_buffers_type>
  58 {
  59 #ifndef BOOST_NO_EXCEPTIONS
  60     try
  61     {
  62         boost::optional<typename
  63             DynamicBuffer::mutable_buffers_type> result;
  64         result.emplace(buffer.prepare(size));
  65         ec = {};
  66         return result;
  67     }
  68     catch(std::length_error const&)
  69     {
  70         ec = ev;
  71     }
  72     return boost::none;
  73
  74 #else
  75     return dynamic_buffer_prepare_noexcept(
  76         buffer, size, ec, ev);
  77 #endif
  78 }
  79
  80 } // detail
  81 } // beast
  82 } // boost
  83
  84 #endif