| // |
| // buffered_read_stream.hpp |
| // ~~~~~~~~~~~~~~~~~~~~~~~~ |
| // |
| // Copyright (c) 2003-2014 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 ASIO_BUFFERED_READ_STREAM_HPP |
| #define ASIO_BUFFERED_READ_STREAM_HPP |
| |
| #if defined(_MSC_VER) && (_MSC_VER >= 1200) |
| # pragma once |
| #endif // defined(_MSC_VER) && (_MSC_VER >= 1200) |
| |
| #include "asio/detail/config.hpp" |
| #include <cstddef> |
| #include "asio/async_result.hpp" |
| #include "asio/buffered_read_stream_fwd.hpp" |
| #include "asio/buffer.hpp" |
| #include "asio/detail/bind_handler.hpp" |
| #include "asio/detail/buffer_resize_guard.hpp" |
| #include "asio/detail/buffered_stream_storage.hpp" |
| #include "asio/detail/noncopyable.hpp" |
| #include "asio/detail/type_traits.hpp" |
| #include "asio/error.hpp" |
| #include "asio/io_service.hpp" |
| |
| #include "asio/detail/push_options.hpp" |
| |
| namespace asio { |
| |
| /// Adds buffering to the read-related operations of a stream. |
| /** |
| * The buffered_read_stream class template can be used to add buffering to the |
| * synchronous and asynchronous read 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_read_stream |
| : private noncopyable |
| { |
| public: |
| /// The type of the next layer. |
| typedef typename 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 |
| ASIO_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_read_stream(Arg& a) |
| : next_layer_(a), |
| storage_(default_buffer_size) |
| { |
| } |
| |
| /// Construct, passing the specified argument to initialise the next layer. |
| template <typename Arg> |
| buffered_read_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. |
| asio::io_service& get_io_service() |
| { |
| return next_layer_.get_io_service(); |
| } |
| |
| /// Close the stream. |
| void close() |
| { |
| next_layer_.close(); |
| } |
| |
| /// Close the stream. |
| asio::error_code close(asio::error_code& ec) |
| { |
| return next_layer_.close(ec); |
| } |
| |
| /// 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 next_layer_.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, |
| asio::error_code& ec) |
| { |
| return next_layer_.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> |
| ASIO_INITFN_RESULT_TYPE(WriteHandler, |
| void (asio::error_code, std::size_t)) |
| async_write_some(const ConstBufferSequence& buffers, |
| ASIO_MOVE_ARG(WriteHandler) handler) |
| { |
| detail::async_result_init< |
| WriteHandler, void (asio::error_code, std::size_t)> init( |
| ASIO_MOVE_CAST(WriteHandler)(handler)); |
| |
| next_layer_.async_write_some(buffers, |
| ASIO_MOVE_CAST(ASIO_HANDLER_TYPE(WriteHandler, |
| void (asio::error_code, std::size_t)))(init.handler)); |
| |
| return init.result.get(); |
| } |
| |
| /// 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(); |
| |
| /// 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(asio::error_code& ec); |
| |
| /// Start an asynchronous fill. |
| template <typename ReadHandler> |
| ASIO_INITFN_RESULT_TYPE(ReadHandler, |
| void (asio::error_code, std::size_t)) |
| async_fill(ASIO_MOVE_ARG(ReadHandler) 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); |
| |
| /// 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, |
| asio::error_code& 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> |
| ASIO_INITFN_RESULT_TYPE(ReadHandler, |
| void (asio::error_code, std::size_t)) |
| async_read_some(const MutableBufferSequence& buffers, |
| ASIO_MOVE_ARG(ReadHandler) 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); |
| |
| /// 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, |
| asio::error_code& ec); |
| |
| /// Determine the amount of data that may be read without blocking. |
| std::size_t in_avail() |
| { |
| return storage_.size(); |
| } |
| |
| /// Determine the amount of data that may be read without blocking. |
| std::size_t in_avail(asio::error_code& ec) |
| { |
| ec = asio::error_code(); |
| return storage_.size(); |
| } |
| |
| private: |
| /// Copy data out of the internal buffer to the specified target buffer. |
| /// Returns the number of bytes copied. |
| template <typename MutableBufferSequence> |
| std::size_t copy(const MutableBufferSequence& buffers) |
| { |
| std::size_t bytes_copied = asio::buffer_copy( |
| buffers, storage_.data(), storage_.size()); |
| storage_.consume(bytes_copied); |
| return bytes_copied; |
| } |
| |
| /// Copy data from the internal buffer to the specified target buffer, without |
| /// removing the data from the internal buffer. Returns the number of bytes |
| /// copied. |
| template <typename MutableBufferSequence> |
| std::size_t peek_copy(const MutableBufferSequence& buffers) |
| { |
| return asio::buffer_copy(buffers, storage_.data(), storage_.size()); |
| } |
| |
| /// The next layer. |
| Stream next_layer_; |
| |
| // The data in the buffer. |
| detail::buffered_stream_storage storage_; |
| }; |
| |
| } // namespace asio |
| |
| #include "asio/detail/pop_options.hpp" |
| |
| #include "asio/impl/buffered_read_stream.hpp" |
| |
| #endif // ASIO_BUFFERED_READ_STREAM_HPP |