/Src/Dependencies/Boost/boost/asio/buffered_write_stream.hpp
http://hadesmem.googlecode.com/ · C++ Header · 353 lines · 245 code · 47 blank · 61 comment · 16 complexity · 12d212c55f58b182124c375f6252043b MD5 · raw file
- //
- // buffered_write_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_WRITE_STREAM_HPP
- #define BOOST_ASIO_BUFFERED_WRITE_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/type_traits/remove_reference.hpp>
- #include <boost/asio/buffered_write_stream_fwd.hpp>
- #include <boost/asio/buffer.hpp>
- #include <boost/asio/completion_condition.hpp>
- #include <boost/asio/detail/bind_handler.hpp>
- #include <boost/asio/detail/buffered_stream_storage.hpp>
- #include <boost/asio/detail/noncopyable.hpp>
- #include <boost/asio/error.hpp>
- #include <boost/asio/io_service.hpp>
- #include <boost/asio/write.hpp>
- #include <boost/asio/detail/push_options.hpp>
- namespace boost {
- namespace asio {
- /// Adds buffering to the write-related operations of a stream.
- /**
- * The buffered_write_stream class template can be used to add buffering to the
- * synchronous and asynchronous 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_write_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;
- #if defined(GENERATING_DOCUMENTATION)
- /// The default buffer size.
- static const std::size_t default_buffer_size = implementation_defined;
- #else
- BOOST_STATIC_CONSTANT(std::size_t, default_buffer_size = 1024);
- #endif
- /// Construct, passing the specified argument to initialise the next layer.
- template <typename Arg>
- explicit buffered_write_stream(Arg& a)
- : next_layer_(a),
- storage_(default_buffer_size)
- {
- }
- /// Construct, passing the specified argument to initialise the next layer.
- template <typename Arg>
- buffered_write_stream(Arg& a, std::size_t buffer_size)
- : next_layer_(a),
- storage_(buffer_size)
- {
- }
- /// Get a reference to the next layer.
- next_layer_type& next_layer()
- {
- return next_layer_;
- }
- /// Get a reference to the lowest layer.
- lowest_layer_type& lowest_layer()
- {
- return next_layer_.lowest_layer();
- }
- /// Get a const reference to the lowest layer.
- const lowest_layer_type& lowest_layer() const
- {
- return next_layer_.lowest_layer();
- }
- /// Get the io_service associated with the object.
- boost::asio::io_service& get_io_service()
- {
- return next_layer_.get_io_service();
- }
- /// Close the stream.
- void close()
- {
- next_layer_.close();
- }
- /// Close the stream.
- boost::system::error_code close(boost::system::error_code& ec)
- {
- return next_layer_.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()
- {
- std::size_t bytes_written = write(next_layer_,
- buffer(storage_.data(), storage_.size()));
- storage_.consume(bytes_written);
- return bytes_written;
- }
- /// 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)
- {
- std::size_t bytes_written = write(next_layer_,
- buffer(storage_.data(), storage_.size()),
- transfer_all(), ec);
- storage_.consume(bytes_written);
- return bytes_written;
- }
- template <typename WriteHandler>
- class flush_handler
- {
- public:
- flush_handler(boost::asio::io_service& io_service,
- detail::buffered_stream_storage& storage, WriteHandler handler)
- : io_service_(io_service),
- storage_(storage),
- handler_(handler)
- {
- }
- void operator()(const boost::system::error_code& ec,
- std::size_t bytes_written)
- {
- storage_.consume(bytes_written);
- io_service_.dispatch(detail::bind_handler(handler_, ec, bytes_written));
- }
- private:
- boost::asio::io_service& io_service_;
- detail::buffered_stream_storage& storage_;
- WriteHandler handler_;
- };
- /// Start an asynchronous flush.
- template <typename WriteHandler>
- void async_flush(WriteHandler handler)
- {
- async_write(next_layer_, buffer(storage_.data(), storage_.size()),
- flush_handler<WriteHandler>(get_io_service(), storage_, 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)
- {
- if (boost::asio::buffer_size(buffers) == 0)
- return 0;
- if (storage_.size() == storage_.capacity())
- flush();
- return copy(buffers);
- }
- /// Write the given data to the stream. Returns the number of bytes written,
- /// or 0 if an error occurred and the error handler did not throw.
- template <typename ConstBufferSequence>
- std::size_t write_some(const ConstBufferSequence& buffers,
- boost::system::error_code& ec)
- {
- ec = boost::system::error_code();
- if (boost::asio::buffer_size(buffers) == 0)
- return 0;
- if (storage_.size() == storage_.capacity() && !flush(ec))
- return 0;
- return copy(buffers);
- }
- template <typename ConstBufferSequence, typename WriteHandler>
- class write_some_handler
- {
- public:
- write_some_handler(boost::asio::io_service& io_service,
- detail::buffered_stream_storage& storage,
- const ConstBufferSequence& buffers, WriteHandler handler)
- : io_service_(io_service),
- storage_(storage),
- buffers_(buffers),
- handler_(handler)
- {
- }
- void operator()(const boost::system::error_code& ec, std::size_t)
- {
- if (ec)
- {
- std::size_t length = 0;
- io_service_.dispatch(detail::bind_handler(handler_, ec, length));
- }
- else
- {
- std::size_t orig_size = storage_.size();
- std::size_t space_avail = storage_.capacity() - orig_size;
- std::size_t bytes_avail = boost::asio::buffer_size(buffers_);
- std::size_t length = bytes_avail < space_avail
- ? bytes_avail : space_avail;
- storage_.resize(orig_size + length);
- std::size_t bytes_copied = boost::asio::buffer_copy(
- storage_.data(), buffers_, length);
- io_service_.dispatch(detail::bind_handler(handler_, ec, bytes_copied));
- }
- }
- private:
- boost::asio::io_service& io_service_;
- detail::buffered_stream_storage& storage_;
- ConstBufferSequence buffers_;
- WriteHandler handler_;
- };
- /// 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)
- {
- if (boost::asio::buffer_size(buffers) == 0)
- {
- get_io_service().post(detail::bind_handler(
- handler, boost::system::error_code(), 0));
- }
- else if (storage_.size() == storage_.capacity())
- {
- async_flush(write_some_handler<ConstBufferSequence, WriteHandler>(
- get_io_service(), storage_, buffers, handler));
- }
- else
- {
- std::size_t bytes_copied = copy(buffers);
- get_io_service().post(detail::bind_handler(
- handler, boost::system::error_code(), bytes_copied));
- }
- }
- /// 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 next_layer_.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 next_layer_.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)
- {
- next_layer_.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 next_layer_.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 next_layer_.peek(buffers, ec);
- }
- /// Determine the amount of data that may be read without blocking.
- std::size_t in_avail()
- {
- return next_layer_.in_avail();
- }
- /// Determine the amount of data that may be read without blocking.
- std::size_t in_avail(boost::system::error_code& ec)
- {
- return next_layer_.in_avail(ec);
- }
- private:
- /// Copy data into the internal buffer from the specified source buffer.
- /// Returns the number of bytes copied.
- template <typename ConstBufferSequence>
- std::size_t copy(const ConstBufferSequence& buffers)
- {
- std::size_t orig_size = storage_.size();
- std::size_t space_avail = storage_.capacity() - orig_size;
- std::size_t bytes_avail = boost::asio::buffer_size(buffers);
- std::size_t length = bytes_avail < space_avail ? bytes_avail : space_avail;
- storage_.resize(orig_size + length);
- return boost::asio::buffer_copy(storage_.data(), buffers, length);
- }
- /// The next layer.
- Stream next_layer_;
- // The data in the buffer.
- detail::buffered_stream_storage storage_;
- };
- } // namespace asio
- } // namespace boost
- #include <boost/asio/detail/pop_options.hpp>
- #endif // BOOST_ASIO_BUFFERED_WRITE_STREAM_HPP