ext-boost/boost/asio/write_at.hpp

682 lines
28 KiB
C++

//
// write_at.hpp
// ~~~~~~~~~~~~
//
// Copyright (c) 2003-2019 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 BOOST_ASIO_WRITE_AT_HPP
#define BOOST_ASIO_WRITE_AT_HPP
#if defined(_MSC_VER) && (_MSC_VER >= 1200)
# pragma once
#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
#include <boost/asio/detail/config.hpp>
#include <cstddef>
#include <boost/asio/async_result.hpp>
#include <boost/asio/detail/cstdint.hpp>
#include <boost/asio/error.hpp>
#if !defined(BOOST_ASIO_NO_EXTENSIONS)
# include <boost/asio/basic_streambuf_fwd.hpp>
#endif // !defined(BOOST_ASIO_NO_EXTENSIONS)
#include <boost/asio/detail/push_options.hpp>
namespace boost {
namespace asio {
/**
* @defgroup write_at boost::asio::write_at
*
* @brief The @c write_at function is a composed operation that writes 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 boost::system::system_error Thrown on failure.
*
* @par Example
* To write a single data buffer use the @ref buffer function as follows:
* @code boost::asio::write_at(d, 42, boost::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 boost::asio::write_at(
* d, offset, buffers,
* boost::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 boost::asio::write_at(d, 42,
* boost::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 boost::asio::write_at(
* d, offset, buffers,
* boost::asio::transfer_all(), ec); @endcode
*/
template <typename SyncRandomAccessWriteDevice, typename ConstBufferSequence>
std::size_t write_at(SyncRandomAccessWriteDevice& d,
uint64_t offset, const ConstBufferSequence& buffers,
boost::system::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 boost::system::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 boost::system::system_error Thrown on failure.
*
* @par Example
* To write a single data buffer use the @ref buffer function as follows:
* @code boost::asio::write_at(d, 42, boost::asio::buffer(data, size),
* boost::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 boost::system::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, boost::system::error_code& ec);
#if !defined(BOOST_ASIO_NO_EXTENSIONS)
#if !defined(BOOST_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 boost::system::system_error Thrown on failure.
*
* @note This overload is equivalent to calling:
* @code boost::asio::write_at(
* d, 42, b,
* boost::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 boost::asio::write_at(
* d, 42, b,
* boost::asio::transfer_all(), ec); @endcode
*/
template <typename SyncRandomAccessWriteDevice, typename Allocator>
std::size_t write_at(SyncRandomAccessWriteDevice& d,
uint64_t offset, basic_streambuf<Allocator>& b,
boost::system::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 boost::system::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 boost::system::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 boost::system::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,
boost::system::error_code& ec);
#endif // !defined(BOOST_ASIO_NO_IOSTREAM)
#endif // !defined(BOOST_ASIO_NO_EXTENSIONS)
/*@}*/
/**
* @defgroup async_write_at boost::asio::async_write_at
*
* @brief The @c async_write_at function is a composed asynchronous operation
* that writes a certain amount of data at the specified offset before
* completion.
*/
/*@{*/
/// 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 boost::system::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. On
* immediate completion, invocation of the handler will be performed in a
* manner equivalent to using boost::asio::post().
*
* @par Example
* To write a single data buffer use the @ref buffer function as follows:
* @code
* boost::asio::async_write_at(d, 42, boost::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>
BOOST_ASIO_INITFN_RESULT_TYPE(WriteHandler,
void (boost::system::error_code, std::size_t))
async_write_at(AsyncRandomAccessWriteDevice& d, uint64_t offset,
const ConstBufferSequence& buffers,
BOOST_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 boost::system::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 boost::system::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. On
* immediate completion, invocation of the handler will be performed in a
* manner equivalent to using boost::asio::post().
*
* @par Example
* To write a single data buffer use the @ref buffer function as follows:
* @code boost::asio::async_write_at(d, 42,
* boost::asio::buffer(data, size),
* boost::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>
BOOST_ASIO_INITFN_RESULT_TYPE(WriteHandler,
void (boost::system::error_code, std::size_t))
async_write_at(AsyncRandomAccessWriteDevice& d,
uint64_t offset, const ConstBufferSequence& buffers,
CompletionCondition completion_condition,
BOOST_ASIO_MOVE_ARG(WriteHandler) handler);
#if !defined(BOOST_ASIO_NO_EXTENSIONS)
#if !defined(BOOST_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 boost::system::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. On
* immediate completion, invocation of the handler will be performed in a
* manner equivalent to using boost::asio::post().
*/
template <typename AsyncRandomAccessWriteDevice, typename Allocator,
typename WriteHandler>
BOOST_ASIO_INITFN_RESULT_TYPE(WriteHandler,
void (boost::system::error_code, std::size_t))
async_write_at(AsyncRandomAccessWriteDevice& d, uint64_t offset,
basic_streambuf<Allocator>& b, BOOST_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 boost::system::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 boost::system::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. On
* immediate completion, invocation of the handler will be performed in a
* manner equivalent to using boost::asio::post().
*/
template <typename AsyncRandomAccessWriteDevice, typename Allocator,
typename CompletionCondition, typename WriteHandler>
BOOST_ASIO_INITFN_RESULT_TYPE(WriteHandler,
void (boost::system::error_code, std::size_t))
async_write_at(AsyncRandomAccessWriteDevice& d, uint64_t offset,
basic_streambuf<Allocator>& b, CompletionCondition completion_condition,
BOOST_ASIO_MOVE_ARG(WriteHandler) handler);
#endif // !defined(BOOST_ASIO_NO_IOSTREAM)
#endif // !defined(BOOST_ASIO_NO_EXTENSIONS)
/*@}*/
} // namespace asio
} // namespace boost
#include <boost/asio/detail/pop_options.hpp>
#include <boost/asio/impl/write_at.hpp>
#endif // BOOST_ASIO_WRITE_AT_HPP