boost/beast/core/detail/buffer_traits.hpp
//
// Copyright (c) 2016-2019 Vinnie Falco (vinnie dot falco at gmail dot com)
//
// 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)
//
// Official repository: https://github.com/boostorg/beast
//
#ifndef BOOST_BEAST_DETAIL_BUFFER_TRAITS_HPP
#define BOOST_BEAST_DETAIL_BUFFER_TRAITS_HPP
#include <boost/asio/buffer.hpp>
#include <boost/config/workaround.hpp>
#include <boost/type_traits/make_void.hpp>
#include <cstdint>
#include <type_traits>
namespace boost {
namespace beast {
namespace detail {
#if BOOST_WORKAROUND(BOOST_MSVC, < 1910)
template<class T>
struct buffers_iterator_type_helper
{
using type = decltype(
net::buffer_sequence_begin(
std::declval<T const&>()));
};
template<>
struct buffers_iterator_type_helper<
net::const_buffer>
{
using type = net::const_buffer const*;
};
template<>
struct buffers_iterator_type_helper<
net::mutable_buffer>
{
using type = net::mutable_buffer const*;
};
#endif
struct buffer_bytes_impl
{
std::size_t
operator()(net::const_buffer b) const noexcept
{
return net::const_buffer(b).size();
}
std::size_t
operator()(net::mutable_buffer b) const noexcept
{
return net::mutable_buffer(b).size();
}
template<
class B,
class = typename std::enable_if<
net::is_const_buffer_sequence<B>::value>::type>
std::size_t
operator()(B const& b) const noexcept
{
using net::buffer_size;
return buffer_size(b);
}
};
/** Return `true` if a buffer sequence is empty
This is sometimes faster than using @ref buffer_bytes
*/
template<class ConstBufferSequence>
bool
buffers_empty(ConstBufferSequence const& buffers)
{
auto it = net::buffer_sequence_begin(buffers);
auto end = net::buffer_sequence_end(buffers);
while(it != end)
{
if(net::const_buffer(*it).size() > 0)
return false;
++it;
}
return true;
}
} // detail
} // beast
} // boost
#endif