Chris@16: //
Chris@16: // buffered_read_stream.hpp
Chris@16: // ~~~~~~~~~~~~~~~~~~~~~~~~
Chris@16: //
Chris@101: // Copyright (c) 2003-2015 Christopher M. Kohlhoff (chris at kohlhoff dot com)
Chris@16: //
Chris@16: // Distributed under the Boost Software License, Version 1.0. (See accompanying
Chris@16: // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
Chris@16: //
Chris@16: 
Chris@16: #ifndef BOOST_ASIO_BUFFERED_READ_STREAM_HPP
Chris@16: #define BOOST_ASIO_BUFFERED_READ_STREAM_HPP
Chris@16: 
Chris@16: #if defined(_MSC_VER) && (_MSC_VER >= 1200)
Chris@16: # pragma once
Chris@16: #endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
Chris@16: 
Chris@16: #include <boost/asio/detail/config.hpp>
Chris@16: #include <cstddef>
Chris@16: #include <boost/asio/async_result.hpp>
Chris@16: #include <boost/asio/buffered_read_stream_fwd.hpp>
Chris@16: #include <boost/asio/buffer.hpp>
Chris@16: #include <boost/asio/detail/bind_handler.hpp>
Chris@16: #include <boost/asio/detail/buffer_resize_guard.hpp>
Chris@16: #include <boost/asio/detail/buffered_stream_storage.hpp>
Chris@16: #include <boost/asio/detail/noncopyable.hpp>
Chris@16: #include <boost/asio/detail/type_traits.hpp>
Chris@16: #include <boost/asio/error.hpp>
Chris@16: #include <boost/asio/io_service.hpp>
Chris@16: 
Chris@16: #include <boost/asio/detail/push_options.hpp>
Chris@16: 
Chris@16: namespace boost {
Chris@16: namespace asio {
Chris@16: 
Chris@16: /// Adds buffering to the read-related operations of a stream.
Chris@16: /**
Chris@16:  * The buffered_read_stream class template can be used to add buffering to the
Chris@16:  * synchronous and asynchronous read operations of a stream.
Chris@16:  *
Chris@16:  * @par Thread Safety
Chris@16:  * @e Distinct @e objects: Safe.@n
Chris@16:  * @e Shared @e objects: Unsafe.
Chris@16:  *
Chris@16:  * @par Concepts:
Chris@16:  * AsyncReadStream, AsyncWriteStream, Stream, SyncReadStream, SyncWriteStream.
Chris@16:  */
Chris@16: template <typename Stream>
Chris@16: class buffered_read_stream
Chris@16:   : private noncopyable
Chris@16: {
Chris@16: public:
Chris@16:   /// The type of the next layer.
Chris@16:   typedef typename remove_reference<Stream>::type next_layer_type;
Chris@16: 
Chris@16:   /// The type of the lowest layer.
Chris@16:   typedef typename next_layer_type::lowest_layer_type lowest_layer_type;
Chris@16: 
Chris@16: #if defined(GENERATING_DOCUMENTATION)
Chris@16:   /// The default buffer size.
Chris@16:   static const std::size_t default_buffer_size = implementation_defined;
Chris@16: #else
Chris@16:   BOOST_ASIO_STATIC_CONSTANT(std::size_t, default_buffer_size = 1024);
Chris@16: #endif
Chris@16: 
Chris@16:   /// Construct, passing the specified argument to initialise the next layer.
Chris@16:   template <typename Arg>
Chris@16:   explicit buffered_read_stream(Arg& a)
Chris@16:     : next_layer_(a),
Chris@16:       storage_(default_buffer_size)
Chris@16:   {
Chris@16:   }
Chris@16: 
Chris@16:   /// Construct, passing the specified argument to initialise the next layer.
Chris@16:   template <typename Arg>
Chris@16:   buffered_read_stream(Arg& a, std::size_t buffer_size)
Chris@16:     : next_layer_(a),
Chris@16:       storage_(buffer_size)
Chris@16:   {
Chris@16:   }
Chris@16: 
Chris@16:   /// Get a reference to the next layer.
Chris@16:   next_layer_type& next_layer()
Chris@16:   {
Chris@16:     return next_layer_;
Chris@16:   }
Chris@16: 
Chris@16:   /// Get a reference to the lowest layer.
Chris@16:   lowest_layer_type& lowest_layer()
Chris@16:   {
Chris@16:     return next_layer_.lowest_layer();
Chris@16:   }
Chris@16: 
Chris@16:   /// Get a const reference to the lowest layer.
Chris@16:   const lowest_layer_type& lowest_layer() const
Chris@16:   {
Chris@16:     return next_layer_.lowest_layer();
Chris@16:   }
Chris@16: 
Chris@16:   /// Get the io_service associated with the object.
Chris@16:   boost::asio::io_service& get_io_service()
Chris@16:   {
Chris@16:     return next_layer_.get_io_service();
Chris@16:   }
Chris@16: 
Chris@16:   /// Close the stream.
Chris@16:   void close()
Chris@16:   {
Chris@16:     next_layer_.close();
Chris@16:   }
Chris@16: 
Chris@16:   /// Close the stream.
Chris@16:   boost::system::error_code close(boost::system::error_code& ec)
Chris@16:   {
Chris@16:     return next_layer_.close(ec);
Chris@16:   }
Chris@16: 
Chris@16:   /// Write the given data to the stream. Returns the number of bytes written.
Chris@16:   /// Throws an exception on failure.
Chris@16:   template <typename ConstBufferSequence>
Chris@16:   std::size_t write_some(const ConstBufferSequence& buffers)
Chris@16:   {
Chris@16:     return next_layer_.write_some(buffers);
Chris@16:   }
Chris@16: 
Chris@16:   /// Write the given data to the stream. Returns the number of bytes written,
Chris@16:   /// or 0 if an error occurred.
Chris@16:   template <typename ConstBufferSequence>
Chris@16:   std::size_t write_some(const ConstBufferSequence& buffers,
Chris@16:       boost::system::error_code& ec)
Chris@16:   {
Chris@16:     return next_layer_.write_some(buffers, ec);
Chris@16:   }
Chris@16: 
Chris@16:   /// Start an asynchronous write. The data being written must be valid for the
Chris@16:   /// lifetime of the asynchronous operation.
Chris@16:   template <typename ConstBufferSequence, typename WriteHandler>
Chris@16:   BOOST_ASIO_INITFN_RESULT_TYPE(WriteHandler,
Chris@16:       void (boost::system::error_code, std::size_t))
Chris@16:   async_write_some(const ConstBufferSequence& buffers,
Chris@16:       BOOST_ASIO_MOVE_ARG(WriteHandler) handler)
Chris@16:   {
Chris@16:     detail::async_result_init<
Chris@16:       WriteHandler, void (boost::system::error_code, std::size_t)> init(
Chris@16:         BOOST_ASIO_MOVE_CAST(WriteHandler)(handler));
Chris@16: 
Chris@16:     next_layer_.async_write_some(buffers,
Chris@16:         BOOST_ASIO_MOVE_CAST(BOOST_ASIO_HANDLER_TYPE(WriteHandler,
Chris@16:             void (boost::system::error_code, std::size_t)))(init.handler));
Chris@16: 
Chris@16:     return init.result.get();
Chris@16:   }
Chris@16: 
Chris@16:   /// Fill the buffer with some data. Returns the number of bytes placed in the
Chris@16:   /// buffer as a result of the operation. Throws an exception on failure.
Chris@16:   std::size_t fill();
Chris@16: 
Chris@16:   /// Fill the buffer with some data. Returns the number of bytes placed in the
Chris@16:   /// buffer as a result of the operation, or 0 if an error occurred.
Chris@16:   std::size_t fill(boost::system::error_code& ec);
Chris@16: 
Chris@16:   /// Start an asynchronous fill.
Chris@16:   template <typename ReadHandler>
Chris@16:   BOOST_ASIO_INITFN_RESULT_TYPE(ReadHandler,
Chris@16:       void (boost::system::error_code, std::size_t))
Chris@16:   async_fill(BOOST_ASIO_MOVE_ARG(ReadHandler) handler);
Chris@16: 
Chris@16:   /// Read some data from the stream. Returns the number of bytes read. Throws
Chris@16:   /// an exception on failure.
Chris@16:   template <typename MutableBufferSequence>
Chris@16:   std::size_t read_some(const MutableBufferSequence& buffers);
Chris@16: 
Chris@16:   /// Read some data from the stream. Returns the number of bytes read or 0 if
Chris@16:   /// an error occurred.
Chris@16:   template <typename MutableBufferSequence>
Chris@16:   std::size_t read_some(const MutableBufferSequence& buffers,
Chris@16:       boost::system::error_code& ec);
Chris@16: 
Chris@16:   /// Start an asynchronous read. The buffer into which the data will be read
Chris@16:   /// must be valid for the lifetime of the asynchronous operation.
Chris@16:   template <typename MutableBufferSequence, typename ReadHandler>
Chris@16:   BOOST_ASIO_INITFN_RESULT_TYPE(ReadHandler,
Chris@16:       void (boost::system::error_code, std::size_t))
Chris@16:   async_read_some(const MutableBufferSequence& buffers,
Chris@16:       BOOST_ASIO_MOVE_ARG(ReadHandler) handler);
Chris@16: 
Chris@16:   /// Peek at the incoming data on the stream. Returns the number of bytes read.
Chris@16:   /// Throws an exception on failure.
Chris@16:   template <typename MutableBufferSequence>
Chris@16:   std::size_t peek(const MutableBufferSequence& buffers);
Chris@16: 
Chris@16:   /// Peek at the incoming data on the stream. Returns the number of bytes read,
Chris@16:   /// or 0 if an error occurred.
Chris@16:   template <typename MutableBufferSequence>
Chris@16:   std::size_t peek(const MutableBufferSequence& buffers,
Chris@16:       boost::system::error_code& ec);
Chris@16: 
Chris@16:   /// Determine the amount of data that may be read without blocking.
Chris@16:   std::size_t in_avail()
Chris@16:   {
Chris@16:     return storage_.size();
Chris@16:   }
Chris@16: 
Chris@16:   /// Determine the amount of data that may be read without blocking.
Chris@16:   std::size_t in_avail(boost::system::error_code& ec)
Chris@16:   {
Chris@16:     ec = boost::system::error_code();
Chris@16:     return storage_.size();
Chris@16:   }
Chris@16: 
Chris@16: private:
Chris@16:   /// Copy data out of the internal buffer to the specified target buffer.
Chris@16:   /// Returns the number of bytes copied.
Chris@16:   template <typename MutableBufferSequence>
Chris@16:   std::size_t copy(const MutableBufferSequence& buffers)
Chris@16:   {
Chris@16:     std::size_t bytes_copied = boost::asio::buffer_copy(
Chris@16:         buffers, storage_.data(), storage_.size());
Chris@16:     storage_.consume(bytes_copied);
Chris@16:     return bytes_copied;
Chris@16:   }
Chris@16: 
Chris@16:   /// Copy data from the internal buffer to the specified target buffer, without
Chris@16:   /// removing the data from the internal buffer. Returns the number of bytes
Chris@16:   /// copied.
Chris@16:   template <typename MutableBufferSequence>
Chris@16:   std::size_t peek_copy(const MutableBufferSequence& buffers)
Chris@16:   {
Chris@16:     return boost::asio::buffer_copy(buffers, storage_.data(), storage_.size());
Chris@16:   }
Chris@16: 
Chris@16:   /// The next layer.
Chris@16:   Stream next_layer_;
Chris@16: 
Chris@16:   // The data in the buffer.
Chris@16:   detail::buffered_stream_storage storage_;
Chris@16: };
Chris@16: 
Chris@16: } // namespace asio
Chris@16: } // namespace boost
Chris@16: 
Chris@16: #include <boost/asio/detail/pop_options.hpp>
Chris@16: 
Chris@16: #include <boost/asio/impl/buffered_read_stream.hpp>
Chris@16: 
Chris@16: #endif // BOOST_ASIO_BUFFERED_READ_STREAM_HPP