| // |
| // windows/random_access_handle.hpp |
| // ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ |
| // |
| // Copyright (c) 2003-2015 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_WINDOWS_RANDOM_ACCESS_HANDLE_HPP |
| #define ASIO_WINDOWS_RANDOM_ACCESS_HANDLE_HPP |
| |
| #if defined(_MSC_VER) && (_MSC_VER >= 1200) |
| # pragma once |
| #endif // defined(_MSC_VER) && (_MSC_VER >= 1200) |
| |
| #include "asio/detail/config.hpp" |
| #include "asio/windows/overlapped_handle.hpp" |
| |
| #if defined(ASIO_HAS_WINDOWS_RANDOM_ACCESS_HANDLE) \ |
| || defined(GENERATING_DOCUMENTATION) |
| |
| #if defined(ASIO_ENABLE_OLD_SERVICES) |
| # include "asio/windows/basic_random_access_handle.hpp" |
| #endif // defined(ASIO_ENABLE_OLD_SERVICES) |
| |
| #include "asio/detail/push_options.hpp" |
| |
| namespace asio { |
| namespace windows { |
| |
| #if defined(ASIO_ENABLE_OLD_SERVICES) |
| // Typedef for the typical usage of a random-access handle. |
| typedef basic_random_access_handle<> random_access_handle; |
| #else // defined(ASIO_ENABLE_OLD_SERVICES) |
| /// Provides random-access handle functionality. |
| /** |
| * The windows::random_access_handle class provides asynchronous and |
| * blocking random-access handle functionality. |
| * |
| * @par Thread Safety |
| * @e Distinct @e objects: Safe.@n |
| * @e Shared @e objects: Unsafe. |
| */ |
| class random_access_handle |
| : public overlapped_handle |
| { |
| public: |
| /// Construct a random_access_handle without opening it. |
| /** |
| * This constructor creates a random-access handle without opening it. The |
| * handle needs to be opened before data can be written to or read from it. |
| * |
| * @param io_context The io_context object that the random-access handle will |
| * use to dispatch handlers for any asynchronous operations performed on the |
| * handle. |
| */ |
| explicit random_access_handle(asio::io_context& io_context) |
| : overlapped_handle(io_context) |
| { |
| } |
| |
| /// Construct a random_access_handle on an existing native handle. |
| /** |
| * This constructor creates a random-access handle object to hold an existing |
| * native handle. |
| * |
| * @param io_context The io_context object that the random-access handle will |
| * use to dispatch handlers for any asynchronous operations performed on the |
| * handle. |
| * |
| * @param handle The new underlying handle implementation. |
| * |
| * @throws asio::system_error Thrown on failure. |
| */ |
| random_access_handle(asio::io_context& io_context, |
| const native_handle_type& handle) |
| : overlapped_handle(io_context, handle) |
| { |
| } |
| |
| #if defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION) |
| /// Move-construct a random_access_handle from another. |
| /** |
| * This constructor moves a random-access handle from one object to another. |
| * |
| * @param other The other random_access_handle object from which the |
| * move will occur. |
| * |
| * @note Following the move, the moved-from object is in the same state as if |
| * constructed using the @c random_access_handle(io_context&) |
| * constructor. |
| */ |
| random_access_handle(random_access_handle&& other) |
| : overlapped_handle(std::move(other)) |
| { |
| } |
| |
| /// Move-assign a random_access_handle from another. |
| /** |
| * This assignment operator moves a random-access handle from one object to |
| * another. |
| * |
| * @param other The other random_access_handle object from which the |
| * move will occur. |
| * |
| * @note Following the move, the moved-from object is in the same state as if |
| * constructed using the @c random_access_handle(io_context&) |
| * constructor. |
| */ |
| random_access_handle& operator=(random_access_handle&& other) |
| { |
| overlapped_handle::operator=(std::move(other)); |
| return *this; |
| } |
| #endif // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION) |
| |
| /// Write some data to the handle at the specified offset. |
| /** |
| * This function is used to write data to the random-access handle. The |
| * function call will block until one or more bytes of the data has been |
| * written successfully, or until an error occurs. |
| * |
| * @param offset The offset at which the data will be written. |
| * |
| * @param buffers One or more data buffers to be written to the handle. |
| * |
| * @returns The number of bytes written. |
| * |
| * @throws asio::system_error Thrown on failure. An error code of |
| * asio::error::eof indicates that the connection was closed by the |
| * peer. |
| * |
| * @note The write_some_at operation may not write all of the data. Consider |
| * using the @ref write_at function if you need to ensure that all data is |
| * written before the blocking operation completes. |
| * |
| * @par Example |
| * To write a single data buffer use the @ref buffer function as follows: |
| * @code |
| * handle.write_some_at(42, asio::buffer(data, size)); |
| * @endcode |
| * See the @ref buffer documentation for information on writing multiple |
| * buffers in one go, and how to use it with arrays, boost::array or |
| * std::vector. |
| */ |
| template <typename ConstBufferSequence> |
| std::size_t write_some_at(uint64_t offset, |
| const ConstBufferSequence& buffers) |
| { |
| asio::error_code ec; |
| std::size_t s = this->get_service().write_some_at( |
| this->get_implementation(), offset, buffers, ec); |
| asio::detail::throw_error(ec, "write_some_at"); |
| return s; |
| } |
| |
| /// Write some data to the handle at the specified offset. |
| /** |
| * This function is used to write data to the random-access handle. The |
| * function call will block until one or more bytes of the data has been |
| * written successfully, or until an error occurs. |
| * |
| * @param offset The offset at which the data will be written. |
| * |
| * @param buffers One or more data buffers to be written to the handle. |
| * |
| * @param ec Set to indicate what error occurred, if any. |
| * |
| * @returns The number of bytes written. Returns 0 if an error occurred. |
| * |
| * @note The write_some operation may not transmit all of the data to the |
| * peer. Consider using the @ref write_at function if you need to ensure that |
| * all data is written before the blocking operation completes. |
| */ |
| template <typename ConstBufferSequence> |
| std::size_t write_some_at(uint64_t offset, |
| const ConstBufferSequence& buffers, asio::error_code& ec) |
| { |
| return this->get_service().write_some_at( |
| this->get_implementation(), offset, buffers, ec); |
| } |
| |
| /// Start an asynchronous write at the specified offset. |
| /** |
| * This function is used to asynchronously write data to the random-access |
| * handle. The function call always returns immediately. |
| * |
| * @param offset The offset at which the data will be written. |
| * |
| * @param buffers One or more data buffers to be written to the handle. |
| * Although the buffers object may be copied as necessary, ownership of the |
| * underlying memory blocks is retained by the caller, which must guarantee |
| * that they remain valid until the handler is called. |
| * |
| * @param handler The handler to be called when the write operation completes. |
| * Copies will be made of the handler as required. The function signature of |
| * the handler must be: |
| * @code void handler( |
| * const asio::error_code& error, // Result of operation. |
| * std::size_t bytes_transferred // Number of bytes written. |
| * ); @endcode |
| * Regardless of whether the asynchronous operation completes immediately or |
| * not, the handler will not be invoked from within this function. Invocation |
| * of the handler will be performed in a manner equivalent to using |
| * asio::io_context::post(). |
| * |
| * @note The write operation may not transmit all of the data to the peer. |
| * Consider using the @ref async_write_at function if you need to ensure that |
| * all data is written before the asynchronous operation completes. |
| * |
| * @par Example |
| * To write a single data buffer use the @ref buffer function as follows: |
| * @code |
| * handle.async_write_some_at(42, asio::buffer(data, size), handler); |
| * @endcode |
| * See the @ref buffer documentation for information on writing multiple |
| * buffers in one go, and how to use it with arrays, boost::array or |
| * std::vector. |
| */ |
| template <typename ConstBufferSequence, typename WriteHandler> |
| ASIO_INITFN_RESULT_TYPE(WriteHandler, |
| void (asio::error_code, std::size_t)) |
| async_write_some_at(uint64_t offset, |
| const ConstBufferSequence& buffers, |
| ASIO_MOVE_ARG(WriteHandler) handler) |
| { |
| // If you get an error on the following line it means that your handler does |
| // not meet the documented type requirements for a WriteHandler. |
| ASIO_WRITE_HANDLER_CHECK(WriteHandler, handler) type_check; |
| |
| asio::async_completion<WriteHandler, |
| void (asio::error_code, std::size_t)> init(handler); |
| |
| this->get_service().async_write_some_at(this->get_implementation(), |
| offset, buffers, init.completion_handler); |
| |
| return init.result.get(); |
| } |
| |
| /// Read some data from the handle at the specified offset. |
| /** |
| * This function is used to read data from the random-access handle. The |
| * function call will block until one or more bytes of data has been read |
| * successfully, or until an error occurs. |
| * |
| * @param offset The offset at which the data will be read. |
| * |
| * @param buffers One or more buffers into which the data will be read. |
| * |
| * @returns The number of bytes read. |
| * |
| * @throws asio::system_error Thrown on failure. An error code of |
| * asio::error::eof indicates that the connection was closed by the |
| * peer. |
| * |
| * @note The read_some operation may not read all of the requested number of |
| * bytes. Consider using the @ref read_at function if you need to ensure that |
| * the requested amount of data is read before the blocking operation |
| * completes. |
| * |
| * @par Example |
| * To read into a single data buffer use the @ref buffer function as follows: |
| * @code |
| * handle.read_some_at(42, asio::buffer(data, size)); |
| * @endcode |
| * See the @ref buffer documentation for information on reading into multiple |
| * buffers in one go, and how to use it with arrays, boost::array or |
| * std::vector. |
| */ |
| template <typename MutableBufferSequence> |
| std::size_t read_some_at(uint64_t offset, |
| const MutableBufferSequence& buffers) |
| { |
| asio::error_code ec; |
| std::size_t s = this->get_service().read_some_at( |
| this->get_implementation(), offset, buffers, ec); |
| asio::detail::throw_error(ec, "read_some_at"); |
| return s; |
| } |
| |
| /// Read some data from the handle at the specified offset. |
| /** |
| * This function is used to read data from the random-access handle. The |
| * function call will block until one or more bytes of data has been read |
| * successfully, or until an error occurs. |
| * |
| * @param offset The offset at which the data will be read. |
| * |
| * @param buffers One or more buffers into which the data will be read. |
| * |
| * @param ec Set to indicate what error occurred, if any. |
| * |
| * @returns The number of bytes read. Returns 0 if an error occurred. |
| * |
| * @note The read_some operation may not read all of the requested number of |
| * bytes. Consider using the @ref read_at function if you need to ensure that |
| * the requested amount of data is read before the blocking operation |
| * completes. |
| */ |
| template <typename MutableBufferSequence> |
| std::size_t read_some_at(uint64_t offset, |
| const MutableBufferSequence& buffers, asio::error_code& ec) |
| { |
| return this->get_service().read_some_at( |
| this->get_implementation(), offset, buffers, ec); |
| } |
| |
| /// Start an asynchronous read at the specified offset. |
| /** |
| * This function is used to asynchronously read data from the random-access |
| * handle. The function call always returns immediately. |
| * |
| * @param offset The offset at which the data will be read. |
| * |
| * @param buffers One or more buffers into which the data will be read. |
| * Although the buffers object may be copied as necessary, ownership of the |
| * underlying memory blocks is retained by the caller, which must guarantee |
| * that they remain valid until the handler is called. |
| * |
| * @param handler The handler to be called when the read operation completes. |
| * Copies will be made of the handler as required. The function signature of |
| * the handler must be: |
| * @code void handler( |
| * const asio::error_code& error, // Result of operation. |
| * std::size_t bytes_transferred // Number of bytes read. |
| * ); @endcode |
| * Regardless of whether the asynchronous operation completes immediately or |
| * not, the handler will not be invoked from within this function. Invocation |
| * of the handler will be performed in a manner equivalent to using |
| * asio::io_context::post(). |
| * |
| * @note The read operation may not read all of the requested number of bytes. |
| * Consider using the @ref async_read_at function if you need to ensure that |
| * the requested amount of data is read before the asynchronous operation |
| * completes. |
| * |
| * @par Example |
| * To read into a single data buffer use the @ref buffer function as follows: |
| * @code |
| * handle.async_read_some_at(42, asio::buffer(data, size), handler); |
| * @endcode |
| * See the @ref buffer documentation for information on reading into multiple |
| * buffers in one go, and how to use it with arrays, boost::array or |
| * std::vector. |
| */ |
| template <typename MutableBufferSequence, typename ReadHandler> |
| ASIO_INITFN_RESULT_TYPE(ReadHandler, |
| void (asio::error_code, std::size_t)) |
| async_read_some_at(uint64_t offset, |
| const MutableBufferSequence& buffers, |
| ASIO_MOVE_ARG(ReadHandler) handler) |
| { |
| // If you get an error on the following line it means that your handler does |
| // not meet the documented type requirements for a ReadHandler. |
| ASIO_READ_HANDLER_CHECK(ReadHandler, handler) type_check; |
| |
| asio::async_completion<ReadHandler, |
| void (asio::error_code, std::size_t)> init(handler); |
| |
| this->get_service().async_read_some_at(this->get_implementation(), |
| offset, buffers, init.completion_handler); |
| |
| return init.result.get(); |
| } |
| }; |
| #endif // defined(ASIO_ENABLE_OLD_SERVICES) |
| |
| } // namespace windows |
| } // namespace asio |
| |
| #include "asio/detail/pop_options.hpp" |
| |
| #endif // defined(ASIO_HAS_WINDOWS_RANDOM_ACCESS_HANDLE) |
| // || defined(GENERATING_DOCUMENTATION) |
| |
| #endif // ASIO_WINDOWS_RANDOM_ACCESS_HANDLE_HPP |