//
// buffered_stream.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_BUFFERED_STREAM_HPP
#define BOOST_ASIO_BUFFERED_STREAM_HPP
#if defined(_MSC_VER) && (_MSC_VER >= 1200)
# pragma once
#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
#include <boost/asio/detail/config.hpp>
#include <cstddef>
#include <boost/asio/buffered_read_stream.hpp>
#include <boost/asio/buffered_write_stream.hpp>
#include <boost/asio/buffered_stream_fwd.hpp>
#include <boost/asio/detail/noncopyable.hpp>
#include <boost/asio/error.hpp>
#include <boost/asio/io_service.hpp>
#include <boost/asio/detail/push_options.hpp>
namespace boost {
namespace asio {
/// Adds buffering to the read- and write-related operations of a stream.
/**
* The buffered_stream class template can be used to add buffering to the
* synchronous and asynchronous read and write operations of a stream.
*
* @par Thread Safety
* @e Distinct @e objects: Safe.@n
* @e Shared @e objects: Unsafe.
*
* @par Concepts:
* AsyncReadStream, AsyncWriteStream, Stream, SyncReadStream, SyncWriteStream.
*/
template <typename Stream>
class buffered_stream
: private noncopyable
{
public:
/// The type of the next layer.
typedef typename boost::remove_reference<Stream>::type next_layer_type;
/// The type of the lowest layer.
typedef typename next_layer_type::lowest_layer_type lowest_layer_type;
/// Construct, passing the specified argument to initialise the next layer.
template <typename Arg>
explicit buffered_stream(Arg& a)
: inner_stream_impl_(a),
stream_impl_(inner_stream_impl_)
{
}
/// Construct, passing the specified argument to initialise the next layer.
template <typename Arg>
explicit buffered_stream(Arg& a, std::size_t read_buffer_size,
std::size_t write_buffer_size)
: inner_stream_impl_(a, write_buffer_size),
stream_impl_(inner_stream_impl_, read_buffer_size)
{
}
/// Get a reference to the next layer.
next_layer_type& next_layer()
{
return stream_impl_.next_layer().next_layer();
}
/// Get a reference to the lowest layer.
lowest_layer_type& lowest_layer()
{
return stream_impl_.lowest_layer();
}
/// Get a const reference to the lowest layer.
const lowest_layer_type& lowest_layer() const
{
return stream_impl_.lowest_layer();
}
/// Get the io_service associated with the object.
boost::asio::io_service& get_io_service()
{
return stream_impl_.get_io_service();
}
/// Close the stream.
void close()
{
stream_impl_.close();
}
/// Close the stream.
boost::system::error_code close(boost::system::error_code& ec)
{
return stream_impl_.close(ec);
}
/// Flush all data from the buffer to the next layer. Returns the number of
/// bytes written to the next layer on the last write operation. Throws an
/// exception on failure.
std::size_t flush()
{
return stream_impl_.next_layer().flush();
}
/// Flush all data from the buffer to the next layer. Returns the number of
/// bytes written to the next layer on the last write operation, or 0 if an
/// error occurred.
std::size_t flush(boost::system::error_code& ec)
{
return stream_impl_.next_layer().flush(ec);
}
/// Start an asynchronous flush.
template <typename WriteHandler>
void async_flush(WriteHandler handler)
{
return stream_impl_.next_layer().async_flush(handler);
}
/// Write the given data to the stream. Returns the number of bytes written.
/// Throws an exception on failure.
template <typename ConstBufferSequence>
std::size_t write_some(const ConstBufferSequence& buffers)
{
return stream_impl_.write_some(buffers);
}
/// Write the given data to the stream. Returns the number of bytes written,
/// or 0 if an error occurred.
template <typename ConstBufferSequence>
std::size_t write_some(const ConstBufferSequence& buffers,
boost::system::error_code& ec)
{
return stream_impl_.write_some(buffers, ec);
}
/// Start an asynchronous write. The data being written must be valid for the
/// lifetime of the asynchronous operation.
template <typename ConstBufferSequence, typename WriteHandler>
void async_write_some(const ConstBufferSequence& buffers,
WriteHandler handler)
{
stream_impl_.async_write_some(buffers, handler);
}
/// Fill the buffer with some data. Returns the number of bytes placed in the
/// buffer as a result of the operation. Throws an exception on failure.
std::size_t fill()
{
return stream_impl_.fill();
}
/// Fill the buffer with some data. Returns the number of bytes placed in the
/// buffer as a result of the operation, or 0 if an error occurred.
std::size_t fill(boost::system::error_code& ec)
{
return stream_impl_.fill(ec);
}
/// Start an asynchronous fill.
template <typename ReadHandler>
void async_fill(ReadHandler handler)
{
stream_impl_.async_fill(handler);
}
/// Read some data from the stream. Returns the number of bytes read. Throws
/// an exception on failure.
template <typename MutableBufferSequence>
std::size_t read_some(const MutableBufferSequence& buffers)
{
return stream_impl_.read_some(buffers);
}
/// Read some data from the stream. Returns the number of bytes read or 0 if
/// an error occurred.
template <typename MutableBufferSequence>
std::size_t read_some(const MutableBufferSequence& buffers,
boost::system::error_code& ec)
{
return stream_impl_.read_some(buffers, ec);
}
/// Start an asynchronous read. The buffer into which the data will be read
/// must be valid for the lifetime of the asynchronous operation.
template <typename MutableBufferSequence, typename ReadHandler>
void async_read_some(const MutableBufferSequence& buffers,
ReadHandler handler)
{
stream_impl_.async_read_some(buffers, handler);
}
/// Peek at the incoming data on the stream. Returns the number of bytes read.
/// Throws an exception on failure.
template <typename MutableBufferSequence>
std::size_t peek(const MutableBufferSequence& buffers)
{
return stream_impl_.peek(buffers);
}
/// Peek at the incoming data on the stream. Returns the number of bytes read,
/// or 0 if an error occurred.
template <typename MutableBufferSequence>
std::size_t peek(const MutableBufferSequence& buffers,
boost::system::error_code& ec)
{
return stream_impl_.peek(buffers, ec);
}
/// Determine the amount of data that may be read without blocking.
std::size_t in_avail()
{
return stream_impl_.in_avail();
}
/// Determine the amount of data that may be read without blocking.
std::size_t in_avail(boost::system::error_code& ec)
{
return stream_impl_.in_avail(ec);
}
private:
// The buffered write stream.
typedef buffered_write_stream<Stream> write_stream_type;
write_stream_type inner_stream_impl_;
// The buffered read stream.
typedef buffered_read_stream<write_stream_type&> read_stream_type;
read_stream_type stream_impl_;
};
} // namespace asio
} // namespace boost
#include <boost/asio/detail/pop_options.hpp>
#endif // BOOST_ASIO_BUFFERED_STREAM_HPP
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