boost/beast/core/impl/flat_static_buffer.ipp
//
// Copyright (c) 2016-2017 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_IMPL_FLAT_STATIC_BUFFER_IPP
#define BOOST_BEAST_IMPL_FLAT_STATIC_BUFFER_IPP
#include <boost/beast/core/detail/type_traits.hpp>
#include <boost/asio/buffer.hpp>
#include <boost/throw_exception.hpp>
#include <algorithm>
#include <cstring>
#include <iterator>
#include <stdexcept>
namespace boost {
namespace beast {
/* Memory is laid out thusly:
begin_ ..|.. in_ ..|.. out_ ..|.. last_ ..|.. end_
*/
inline
auto
flat_static_buffer_base::
data() const ->
const_buffers_type
{
return {in_, dist(in_, out_)};
}
inline
void
flat_static_buffer_base::
reset()
{
reset_impl();
}
inline
auto
flat_static_buffer_base::
prepare(std::size_t n) ->
mutable_buffers_type
{
return prepare_impl(n);
}
inline
void
flat_static_buffer_base::
reset(void* p, std::size_t n)
{
reset_impl(p, n);
}
template<class>
void
flat_static_buffer_base::
reset_impl()
{
in_ = begin_;
out_ = begin_;
last_ = begin_;
}
template<class>
void
flat_static_buffer_base::
reset_impl(void* p, std::size_t n)
{
begin_ = static_cast<char*>(p);
in_ = begin_;
out_ = begin_;
last_ = begin_;
end_ = begin_ + n;
}
template<class>
auto
flat_static_buffer_base::
prepare_impl(std::size_t n) ->
mutable_buffers_type
{
if(n <= dist(out_, end_))
{
last_ = out_ + n;
return {out_, n};
}
auto const len = size();
if(n > capacity() - len)
BOOST_THROW_EXCEPTION(std::length_error{
"buffer overflow"});
if(len > 0)
std::memmove(begin_, in_, len);
in_ = begin_;
out_ = in_ + len;
last_ = out_ + n;
return {out_, n};
}
template<class>
void
flat_static_buffer_base::
consume_impl(std::size_t n)
{
if(n >= size())
{
in_ = begin_;
out_ = in_;
return;
}
in_ += n;
}
//------------------------------------------------------------------------------
template<std::size_t N>
flat_static_buffer<N>::
flat_static_buffer(flat_static_buffer const& other)
: flat_static_buffer_base(buf_, N)
{
using boost::asio::buffer_copy;
this->commit(buffer_copy(
this->prepare(other.size()), other.data()));
}
template<std::size_t N>
auto
flat_static_buffer<N>::
operator=(flat_static_buffer const& other) ->
flat_static_buffer<N>&
{
using boost::asio::buffer_copy;
this->consume(this->size());
this->commit(buffer_copy(
this->prepare(other.size()), other.data()));
return *this;
}
} // beast
} // boost
#endif