|
- //
- // write_at.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_WRITE_AT_HPP
- #define ASIO_WRITE_AT_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/basic_streambuf_fwd.hpp"
- #include "asio/detail/cstdint.hpp"
- #include "asio/error.hpp"
-
- #include "asio/detail/push_options.hpp"
-
- namespace asio {
-
- /**
- * @defgroup write_at asio::write_at
- *
- * @brief Write a certain amount of data at a specified offset before returning.
- */
- /*@{*/
-
- /// Write all of the supplied data at the specified offset before returning.
- /**
- * This function is used to write a certain number of bytes of data to a random
- * access device at a specified offset. The call will block until one of the
- * following conditions is true:
- *
- * @li All of the data in the supplied buffers has been written. That is, the
- * bytes transferred is equal to the sum of the buffer sizes.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the device's
- * write_some_at function.
- *
- * @param d The device to which the data is to be written. The type must support
- * the SyncRandomAccessWriteDevice concept.
- *
- * @param offset The offset at which the data will be written.
- *
- * @param buffers One or more buffers containing the data to be written. The sum
- * of the buffer sizes indicates the maximum number of bytes to write to the
- * device.
- *
- * @returns The number of bytes transferred.
- *
- * @throws asio::system_error Thrown on failure.
- *
- * @par Example
- * To write a single data buffer use the @ref buffer function as follows:
- * @code asio::write_at(d, 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.
- *
- * @note This overload is equivalent to calling:
- * @code asio::write_at(
- * d, offset, buffers,
- * asio::transfer_all()); @endcode
- */
- template <typename SyncRandomAccessWriteDevice, typename ConstBufferSequence>
- std::size_t write_at(SyncRandomAccessWriteDevice& d,
- uint64_t offset, const ConstBufferSequence& buffers);
-
- /// Write all of the supplied data at the specified offset before returning.
- /**
- * This function is used to write a certain number of bytes of data to a random
- * access device at a specified offset. The call will block until one of the
- * following conditions is true:
- *
- * @li All of the data in the supplied buffers has been written. That is, the
- * bytes transferred is equal to the sum of the buffer sizes.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the device's
- * write_some_at function.
- *
- * @param d The device to which the data is to be written. The type must support
- * the SyncRandomAccessWriteDevice concept.
- *
- * @param offset The offset at which the data will be written.
- *
- * @param buffers One or more buffers containing the data to be written. The sum
- * of the buffer sizes indicates the maximum number of bytes to write to the
- * device.
- *
- * @param ec Set to indicate what error occurred, if any.
- *
- * @returns The number of bytes transferred.
- *
- * @par Example
- * To write a single data buffer use the @ref buffer function as follows:
- * @code asio::write_at(d, 42,
- * asio::buffer(data, size), ec); @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.
- *
- * @note This overload is equivalent to calling:
- * @code asio::write_at(
- * d, offset, buffers,
- * asio::transfer_all(), ec); @endcode
- */
- template <typename SyncRandomAccessWriteDevice, typename ConstBufferSequence>
- std::size_t write_at(SyncRandomAccessWriteDevice& d,
- uint64_t offset, const ConstBufferSequence& buffers,
- asio::error_code& ec);
-
- /// Write a certain amount of data at a specified offset before returning.
- /**
- * This function is used to write a certain number of bytes of data to a random
- * access device at a specified offset. The call will block until one of the
- * following conditions is true:
- *
- * @li All of the data in the supplied buffers has been written. That is, the
- * bytes transferred is equal to the sum of the buffer sizes.
- *
- * @li The completion_condition function object returns 0.
- *
- * This operation is implemented in terms of zero or more calls to the device's
- * write_some_at function.
- *
- * @param d The device to which the data is to be written. The type must support
- * the SyncRandomAccessWriteDevice concept.
- *
- * @param offset The offset at which the data will be written.
- *
- * @param buffers One or more buffers containing the data to be written. The sum
- * of the buffer sizes indicates the maximum number of bytes to write to the
- * device.
- *
- * @param completion_condition The function object to be called to determine
- * whether the write operation is complete. The signature of the function object
- * must be:
- * @code std::size_t completion_condition(
- * // Result of latest write_some_at operation.
- * const asio::error_code& error,
- *
- * // Number of bytes transferred so far.
- * std::size_t bytes_transferred
- * ); @endcode
- * A return value of 0 indicates that the write operation is complete. A
- * non-zero return value indicates the maximum number of bytes to be written on
- * the next call to the device's write_some_at function.
- *
- * @returns The number of bytes transferred.
- *
- * @throws asio::system_error Thrown on failure.
- *
- * @par Example
- * To write a single data buffer use the @ref buffer function as follows:
- * @code asio::write_at(d, 42, asio::buffer(data, size),
- * asio::transfer_at_least(32)); @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 SyncRandomAccessWriteDevice, typename ConstBufferSequence,
- typename CompletionCondition>
- std::size_t write_at(SyncRandomAccessWriteDevice& d,
- uint64_t offset, const ConstBufferSequence& buffers,
- CompletionCondition completion_condition);
-
- /// Write a certain amount of data at a specified offset before returning.
- /**
- * This function is used to write a certain number of bytes of data to a random
- * access device at a specified offset. The call will block until one of the
- * following conditions is true:
- *
- * @li All of the data in the supplied buffers has been written. That is, the
- * bytes transferred is equal to the sum of the buffer sizes.
- *
- * @li The completion_condition function object returns 0.
- *
- * This operation is implemented in terms of zero or more calls to the device's
- * write_some_at function.
- *
- * @param d The device to which the data is to be written. The type must support
- * the SyncRandomAccessWriteDevice concept.
- *
- * @param offset The offset at which the data will be written.
- *
- * @param buffers One or more buffers containing the data to be written. The sum
- * of the buffer sizes indicates the maximum number of bytes to write to the
- * device.
- *
- * @param completion_condition The function object to be called to determine
- * whether the write operation is complete. The signature of the function object
- * must be:
- * @code std::size_t completion_condition(
- * // Result of latest write_some_at operation.
- * const asio::error_code& error,
- *
- * // Number of bytes transferred so far.
- * std::size_t bytes_transferred
- * ); @endcode
- * A return value of 0 indicates that the write operation is complete. A
- * non-zero return value indicates the maximum number of bytes to be written on
- * the next call to the device's write_some_at function.
- *
- * @param ec Set to indicate what error occurred, if any.
- *
- * @returns The number of bytes written. If an error occurs, returns the total
- * number of bytes successfully transferred prior to the error.
- */
- template <typename SyncRandomAccessWriteDevice, typename ConstBufferSequence,
- typename CompletionCondition>
- std::size_t write_at(SyncRandomAccessWriteDevice& d,
- uint64_t offset, const ConstBufferSequence& buffers,
- CompletionCondition completion_condition, asio::error_code& ec);
-
- #if !defined(ASIO_NO_IOSTREAM)
-
- /// Write all of the supplied data at the specified offset before returning.
- /**
- * This function is used to write a certain number of bytes of data to a random
- * access device at a specified offset. The call will block until one of the
- * following conditions is true:
- *
- * @li All of the data in the supplied basic_streambuf has been written.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the device's
- * write_some_at function.
- *
- * @param d The device to which the data is to be written. The type must support
- * the SyncRandomAccessWriteDevice concept.
- *
- * @param offset The offset at which the data will be written.
- *
- * @param b The basic_streambuf object from which data will be written.
- *
- * @returns The number of bytes transferred.
- *
- * @throws asio::system_error Thrown on failure.
- *
- * @note This overload is equivalent to calling:
- * @code asio::write_at(
- * d, 42, b,
- * asio::transfer_all()); @endcode
- */
- template <typename SyncRandomAccessWriteDevice, typename Allocator>
- std::size_t write_at(SyncRandomAccessWriteDevice& d,
- uint64_t offset, basic_streambuf<Allocator>& b);
-
- /// Write all of the supplied data at the specified offset before returning.
- /**
- * This function is used to write a certain number of bytes of data to a random
- * access device at a specified offset. The call will block until one of the
- * following conditions is true:
- *
- * @li All of the data in the supplied basic_streambuf has been written.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the device's
- * write_some_at function.
- *
- * @param d The device to which the data is to be written. The type must support
- * the SyncRandomAccessWriteDevice concept.
- *
- * @param offset The offset at which the data will be written.
- *
- * @param b The basic_streambuf object from which data will be written.
- *
- * @param ec Set to indicate what error occurred, if any.
- *
- * @returns The number of bytes transferred.
- *
- * @note This overload is equivalent to calling:
- * @code asio::write_at(
- * d, 42, b,
- * asio::transfer_all(), ec); @endcode
- */
- template <typename SyncRandomAccessWriteDevice, typename Allocator>
- std::size_t write_at(SyncRandomAccessWriteDevice& d,
- uint64_t offset, basic_streambuf<Allocator>& b,
- asio::error_code& ec);
-
- /// Write a certain amount of data at a specified offset before returning.
- /**
- * This function is used to write a certain number of bytes of data to a random
- * access device at a specified offset. The call will block until one of the
- * following conditions is true:
- *
- * @li All of the data in the supplied basic_streambuf has been written.
- *
- * @li The completion_condition function object returns 0.
- *
- * This operation is implemented in terms of zero or more calls to the device's
- * write_some_at function.
- *
- * @param d The device to which the data is to be written. The type must support
- * the SyncRandomAccessWriteDevice concept.
- *
- * @param offset The offset at which the data will be written.
- *
- * @param b The basic_streambuf object from which data will be written.
- *
- * @param completion_condition The function object to be called to determine
- * whether the write operation is complete. The signature of the function object
- * must be:
- * @code std::size_t completion_condition(
- * // Result of latest write_some_at operation.
- * const asio::error_code& error,
- *
- * // Number of bytes transferred so far.
- * std::size_t bytes_transferred
- * ); @endcode
- * A return value of 0 indicates that the write operation is complete. A
- * non-zero return value indicates the maximum number of bytes to be written on
- * the next call to the device's write_some_at function.
- *
- * @returns The number of bytes transferred.
- *
- * @throws asio::system_error Thrown on failure.
- */
- template <typename SyncRandomAccessWriteDevice, typename Allocator,
- typename CompletionCondition>
- std::size_t write_at(SyncRandomAccessWriteDevice& d, uint64_t offset,
- basic_streambuf<Allocator>& b, CompletionCondition completion_condition);
-
- /// Write a certain amount of data at a specified offset before returning.
- /**
- * This function is used to write a certain number of bytes of data to a random
- * access device at a specified offset. The call will block until one of the
- * following conditions is true:
- *
- * @li All of the data in the supplied basic_streambuf has been written.
- *
- * @li The completion_condition function object returns 0.
- *
- * This operation is implemented in terms of zero or more calls to the device's
- * write_some_at function.
- *
- * @param d The device to which the data is to be written. The type must support
- * the SyncRandomAccessWriteDevice concept.
- *
- * @param offset The offset at which the data will be written.
- *
- * @param b The basic_streambuf object from which data will be written.
- *
- * @param completion_condition The function object to be called to determine
- * whether the write operation is complete. The signature of the function object
- * must be:
- * @code std::size_t completion_condition(
- * // Result of latest write_some_at operation.
- * const asio::error_code& error,
- *
- * // Number of bytes transferred so far.
- * std::size_t bytes_transferred
- * ); @endcode
- * A return value of 0 indicates that the write operation is complete. A
- * non-zero return value indicates the maximum number of bytes to be written on
- * the next call to the device's write_some_at function.
- *
- * @param ec Set to indicate what error occurred, if any.
- *
- * @returns The number of bytes written. If an error occurs, returns the total
- * number of bytes successfully transferred prior to the error.
- */
- template <typename SyncRandomAccessWriteDevice, typename Allocator,
- typename CompletionCondition>
- std::size_t write_at(SyncRandomAccessWriteDevice& d, uint64_t offset,
- basic_streambuf<Allocator>& b, CompletionCondition completion_condition,
- asio::error_code& ec);
-
- #endif // !defined(ASIO_NO_IOSTREAM)
-
- /*@}*/
- /**
- * @defgroup async_write_at asio::async_write_at
- *
- * @brief Start an asynchronous operation to write a certain amount of data at
- * the specified offset.
- */
- /*@{*/
-
- /// Start an asynchronous operation to write all of the supplied data at the
- /// specified offset.
- /**
- * This function is used to asynchronously write a certain number of bytes of
- * data to a random access device at a specified offset. The function call
- * always returns immediately. The asynchronous operation will continue until
- * one of the following conditions is true:
- *
- * @li All of the data in the supplied buffers has been written. That is, the
- * bytes transferred is equal to the sum of the buffer sizes.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the device's
- * async_write_some_at function, and is known as a <em>composed operation</em>.
- * The program must ensure that the device performs no <em>overlapping</em>
- * write operations (such as async_write_at, the device's async_write_some_at
- * function, or any other composed operations that perform writes) until this
- * operation completes. Operations are overlapping if the regions defined by
- * their offsets, and the numbers of bytes to write, intersect.
- *
- * @param d The device to which the data is to be written. The type must support
- * the AsyncRandomAccessWriteDevice concept.
- *
- * @param offset The offset at which the data will be written.
- *
- * @param buffers One or more buffers containing the data to be written.
- * 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(
- * // Result of operation.
- * const asio::error_code& error,
- *
- * // Number of bytes written from the buffers. If an error
- * // occurred, this will be less than the sum of the buffer sizes.
- * std::size_t bytes_transferred
- * ); @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().
- *
- * @par Example
- * To write a single data buffer use the @ref buffer function as follows:
- * @code
- * asio::async_write_at(d, 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 AsyncRandomAccessWriteDevice, typename ConstBufferSequence,
- typename WriteHandler>
- ASIO_INITFN_RESULT_TYPE(WriteHandler,
- void (asio::error_code, std::size_t))
- async_write_at(AsyncRandomAccessWriteDevice& d, uint64_t offset,
- const ConstBufferSequence& buffers,
- ASIO_MOVE_ARG(WriteHandler) handler);
-
- /// Start an asynchronous operation to write a certain amount of data at the
- /// specified offset.
- /**
- * This function is used to asynchronously write a certain number of bytes of
- * data to a random access device at a specified offset. The function call
- * always returns immediately. The asynchronous operation will continue until
- * one of the following conditions is true:
- *
- * @li All of the data in the supplied buffers has been written. That is, the
- * bytes transferred is equal to the sum of the buffer sizes.
- *
- * @li The completion_condition function object returns 0.
- *
- * This operation is implemented in terms of zero or more calls to the device's
- * async_write_some_at function, and is known as a <em>composed operation</em>.
- * The program must ensure that the device performs no <em>overlapping</em>
- * write operations (such as async_write_at, the device's async_write_some_at
- * function, or any other composed operations that perform writes) until this
- * operation completes. Operations are overlapping if the regions defined by
- * their offsets, and the numbers of bytes to write, intersect.
- *
- * @param d The device to which the data is to be written. The type must support
- * the AsyncRandomAccessWriteDevice concept.
- *
- * @param offset The offset at which the data will be written.
- *
- * @param buffers One or more buffers containing the data to be written.
- * 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 completion_condition The function object to be called to determine
- * whether the write operation is complete. The signature of the function object
- * must be:
- * @code std::size_t completion_condition(
- * // Result of latest async_write_some_at operation.
- * const asio::error_code& error,
- *
- * // Number of bytes transferred so far.
- * std::size_t bytes_transferred
- * ); @endcode
- * A return value of 0 indicates that the write operation is complete. A
- * non-zero return value indicates the maximum number of bytes to be written on
- * the next call to the device's async_write_some_at function.
- *
- * @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(
- * // Result of operation.
- * const asio::error_code& error,
- *
- * // Number of bytes written from the buffers. If an error
- * // occurred, this will be less than the sum of the buffer sizes.
- * std::size_t bytes_transferred
- * ); @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().
- *
- * @par Example
- * To write a single data buffer use the @ref buffer function as follows:
- * @code asio::async_write_at(d, 42,
- * asio::buffer(data, size),
- * asio::transfer_at_least(32),
- * 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 AsyncRandomAccessWriteDevice, typename ConstBufferSequence,
- typename CompletionCondition, typename WriteHandler>
- ASIO_INITFN_RESULT_TYPE(WriteHandler,
- void (asio::error_code, std::size_t))
- async_write_at(AsyncRandomAccessWriteDevice& d,
- uint64_t offset, const ConstBufferSequence& buffers,
- CompletionCondition completion_condition,
- ASIO_MOVE_ARG(WriteHandler) handler);
-
- #if !defined(ASIO_NO_IOSTREAM)
-
- /// Start an asynchronous operation to write all of the supplied data at the
- /// specified offset.
- /**
- * This function is used to asynchronously write a certain number of bytes of
- * data to a random access device at a specified offset. The function call
- * always returns immediately. The asynchronous operation will continue until
- * one of the following conditions is true:
- *
- * @li All of the data in the supplied basic_streambuf has been written.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the device's
- * async_write_some_at function, and is known as a <em>composed operation</em>.
- * The program must ensure that the device performs no <em>overlapping</em>
- * write operations (such as async_write_at, the device's async_write_some_at
- * function, or any other composed operations that perform writes) until this
- * operation completes. Operations are overlapping if the regions defined by
- * their offsets, and the numbers of bytes to write, intersect.
- *
- * @param d The device to which the data is to be written. The type must support
- * the AsyncRandomAccessWriteDevice concept.
- *
- * @param offset The offset at which the data will be written.
- *
- * @param b A basic_streambuf object from which data will be written. Ownership
- * of the streambuf is retained by the caller, which must guarantee that it
- * remains 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(
- * // Result of operation.
- * const asio::error_code& error,
- *
- * // Number of bytes written from the buffers. If an error
- * // occurred, this will be less than the sum of the buffer sizes.
- * std::size_t bytes_transferred
- * ); @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().
- */
- template <typename AsyncRandomAccessWriteDevice, typename Allocator,
- typename WriteHandler>
- ASIO_INITFN_RESULT_TYPE(WriteHandler,
- void (asio::error_code, std::size_t))
- async_write_at(AsyncRandomAccessWriteDevice& d, uint64_t offset,
- basic_streambuf<Allocator>& b, ASIO_MOVE_ARG(WriteHandler) handler);
-
- /// Start an asynchronous operation to write a certain amount of data at the
- /// specified offset.
- /**
- * This function is used to asynchronously write a certain number of bytes of
- * data to a random access device at a specified offset. The function call
- * always returns immediately. The asynchronous operation will continue until
- * one of the following conditions is true:
- *
- * @li All of the data in the supplied basic_streambuf has been written.
- *
- * @li The completion_condition function object returns 0.
- *
- * This operation is implemented in terms of zero or more calls to the device's
- * async_write_some_at function, and is known as a <em>composed operation</em>.
- * The program must ensure that the device performs no <em>overlapping</em>
- * write operations (such as async_write_at, the device's async_write_some_at
- * function, or any other composed operations that perform writes) until this
- * operation completes. Operations are overlapping if the regions defined by
- * their offsets, and the numbers of bytes to write, intersect.
- *
- * @param d The device to which the data is to be written. The type must support
- * the AsyncRandomAccessWriteDevice concept.
- *
- * @param offset The offset at which the data will be written.
- *
- * @param b A basic_streambuf object from which data will be written. Ownership
- * of the streambuf is retained by the caller, which must guarantee that it
- * remains valid until the handler is called.
- *
- * @param completion_condition The function object to be called to determine
- * whether the write operation is complete. The signature of the function object
- * must be:
- * @code std::size_t completion_condition(
- * // Result of latest async_write_some_at operation.
- * const asio::error_code& error,
- *
- * // Number of bytes transferred so far.
- * std::size_t bytes_transferred
- * ); @endcode
- * A return value of 0 indicates that the write operation is complete. A
- * non-zero return value indicates the maximum number of bytes to be written on
- * the next call to the device's async_write_some_at function.
- *
- * @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(
- * // Result of operation.
- * const asio::error_code& error,
- *
- * // Number of bytes written from the buffers. If an error
- * // occurred, this will be less than the sum of the buffer sizes.
- * std::size_t bytes_transferred
- * ); @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().
- */
- template <typename AsyncRandomAccessWriteDevice, typename Allocator,
- typename CompletionCondition, typename WriteHandler>
- ASIO_INITFN_RESULT_TYPE(WriteHandler,
- void (asio::error_code, std::size_t))
- async_write_at(AsyncRandomAccessWriteDevice& d, uint64_t offset,
- basic_streambuf<Allocator>& b, CompletionCondition completion_condition,
- ASIO_MOVE_ARG(WriteHandler) handler);
-
- #endif // !defined(ASIO_NO_IOSTREAM)
-
- /*@}*/
-
- } // namespace asio
-
- #include "asio/detail/pop_options.hpp"
-
- #include "asio/impl/write_at.hpp"
-
- #endif // ASIO_WRITE_AT_HPP
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