//
// detail/buffer_sequence_adapter.hpp
// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
//
// Copyright (c) 2003-2011 Christopher M. Kohlhoff (chris at kohlhoff 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)
//
#ifndef BOOST_ASIO_DETAIL_BUFFER_SEQUENCE_ADAPTER_HPP
#define BOOST_ASIO_DETAIL_BUFFER_SEQUENCE_ADAPTER_HPP
#if defined(_MSC_VER) && (_MSC_VER >= 1200)
# pragma once
#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
#include <boost/asio/detail/config.hpp>
#include <boost/asio/buffer.hpp>
#include <boost/asio/detail/socket_types.hpp>
#include <boost/asio/detail/push_options.hpp>
namespace boost {
namespace asio {
namespace detail {
class buffer_sequence_adapter_base
{
protected:
#if defined(BOOST_WINDOWS) || defined(__CYGWIN__)
typedef WSABUF native_buffer_type;
static void init_native_buffer(WSABUF& buf,
const boost::asio::mutable_buffer& buffer)
{
buf.buf = boost::asio::buffer_cast<char*>(buffer);
buf.len = static_cast<ULONG>(boost::asio::buffer_size(buffer));
}
static void init_native_buffer(WSABUF& buf,
const boost::asio::const_buffer& buffer)
{
buf.buf = const_cast<char*>(boost::asio::buffer_cast<const char*>(buffer));
buf.len = static_cast<ULONG>(boost::asio::buffer_size(buffer));
}
#else // defined(BOOST_WINDOWS) || defined(__CYGWIN__)
typedef iovec native_buffer_type;
static void init_iov_base(void*& base, void* addr)
{
base = addr;
}
template <typename T>
static void init_iov_base(T& base, void* addr)
{
base = static_cast<T>(addr);
}
static void init_native_buffer(iovec& iov,
const boost::asio::mutable_buffer& buffer)
{
init_iov_base(iov.iov_base, boost::asio::buffer_cast<void*>(buffer));
iov.iov_len = boost::asio::buffer_size(buffer);
}
static void init_native_buffer(iovec& iov,
const boost::asio::const_buffer& buffer)
{
init_iov_base(iov.iov_base, const_cast<void*>(
boost::asio::buffer_cast<const void*>(buffer)));
iov.iov_len = boost::asio::buffer_size(buffer);
}
#endif // defined(BOOST_WINDOWS) || defined(__CYGWIN__)
};
// Helper class to translate buffers into the native buffer representation.
template <typename Buffer, typename Buffers>
class buffer_sequence_adapter
: buffer_sequence_adapter_base
{
public:
explicit buffer_sequence_adapter(const Buffers& buffer_sequence)
: count_(0), total_buffer_size_(0)
{
typename Buffers::const_iterator iter = buffer_sequence.begin();
typename Buffers::const_iterator end = buffer_sequence.end();
for (; iter != end && count_ < max_buffers; ++iter, ++count_)
{
Buffer buffer(*iter);
init_native_buffer(buffers_[count_], buffer);
total_buffer_size_ += boost::asio::buffer_size(buffer);
}
}
native_buffer_type* buffers()
{
return buffers_;
}
std::size_t count() const
{
return count_;
}
bool all_empty() const
{
return total_buffer_size_ == 0;
}
static bool all_empty(const Buffers& buffer_sequence)
{
typename Buffers::const_iterator iter = buffer_sequence.begin();
typename Buffers::const_iterator end = buffer_sequence.end();
std::size_t i = 0;
for (; iter != end && i < max_buffers; ++iter, ++i)
if (boost::asio::buffer_size(Buffer(*iter)) > 0)
return false;
return true;
}
static void validate(const Buffers& buffer_sequence)
{
typename Buffers::const_iterator iter = buffer_sequence.begin();
typename Buffers::const_iterator end = buffer_sequence.end();
for (; iter != end; ++iter)
{
Buffer buffer(*iter);
boost::asio::buffer_cast<const void*>(buffer);
}
}
static Buffer first(const Buffers& buffer_sequence)
{
typename Buffers::const_iterator iter = buffer_sequence.begin();
typename Buffers::const_iterator end = buffer_sequence.end();
for (; iter != end; ++iter)
{
Buffer buffer(*iter);
if (boost::asio::buffer_size(buffer) != 0)
return buffer;
}
return Buffer();
}
private:
// The maximum number of buffers to support in a single operation.
enum { max_buffers = 64 < max_iov_len ? 64 : max_iov_len };
native_buffer_type buffers_[max_buffers];
std::size_t count_;
std::size_t total_buffer_size_;
};
template <typename Buffer>
class buffer_sequence_adapter<Buffer, boost::asio::mutable_buffers_1>
: buffer_sequence_adapter_base
{
public:
explicit buffer_sequence_adapter(
const boost::asio::mutable_buffers_1& buffer_sequence)
{
init_native_buffer(buffer_, Buffer(buffer_sequence));
total_buffer_size_ = boost::asio::buffer_size(buffer_sequence);
}
native_buffer_type* buffers()
{
return &buffer_;
}
std::size_t count() const
{
return 1;
}
bool all_empty() const
{
return total_buffer_size_ == 0;
}
static bool all_empty(const boost::asio::mutable_buffers_1& buffer_sequence)
{
return boost::asio::buffer_size(buffer_sequence) == 0;
}
static void validate(const boost::asio::mutable_buffers_1& buffer_sequence)
{
boost::asio::buffer_cast<const void*>(buffer_sequence);
}
static Buffer first(const boost::asio::mutable_buffers_1& buffer_sequence)
{
return Buffer(buffer_sequence);
}
private:
native_buffer_type buffer_;
std::size_t total_buffer_size_;
};
template <typename Buffer>
class buffer_sequence_adapter<Buffer, boost::asio::const_buffers_1>
: buffer_sequence_adapter_base
{
public:
explicit buffer_sequence_adapter(
const boost::asio::const_buffers_1& buffer_sequence)
{
init_native_buffer(buffer_, Buffer(buffer_sequence));
total_buffer_size_ = boost::asio::buffer_size(buffer_sequence);
}
native_buffer_type* buffers()
{
return &buffer_;
}
std::size_t count() const
{
return 1;
}
bool all_empty() const
{
return total_buffer_size_ == 0;
}
static bool all_empty(const boost::asio::const_buffers_1& buffer_sequence)
{
return boost::asio::buffer_size(buffer_sequence) == 0;
}
static void validate(const boost::asio::const_buffers_1& buffer_sequence)
{
boost::asio::buffer_cast<const void*>(buffer_sequence);
}
static Buffer first(const boost::asio::const_buffers_1& buffer_sequence)
{
return Buffer(buffer_sequence);
}
private:
native_buffer_type buffer_;
std::size_t total_buffer_size_;
};
} // namespace detail
} // namespace asio
} // namespace boost
#include <boost/asio/detail/pop_options.hpp>
#endif // BOOST_ASIO_DETAIL_BUFFER_SEQUENCE_ADAPTER_HPP
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