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diff --git a/lib/asio/write_at.hpp b/lib/asio/write_at.hpp new file mode 100644 index 0000000..5018d21 --- /dev/null +++ b/lib/asio/write_at.hpp @@ -0,0 +1,677 @@ +// +// write_at.hpp +// ~~~~~~~~~~~~ +// +// Copyright (c) 2003-2018 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/detail/cstdint.hpp" +#include "asio/error.hpp" + +#if !defined(ASIO_NO_EXTENSIONS) +# include "asio/basic_streambuf_fwd.hpp" +#endif // !defined(ASIO_NO_EXTENSIONS) + +#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_EXTENSIONS) +#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) +#endif // !defined(ASIO_NO_EXTENSIONS) + +/*@}*/ +/** + * @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_EXTENSIONS) +#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) +#endif // !defined(ASIO_NO_EXTENSIONS) + +/*@}*/ + +} // namespace asio + +#include "asio/detail/pop_options.hpp" + +#include "asio/impl/write_at.hpp" + +#endif // ASIO_WRITE_AT_HPP |