Edit: /usr/include/boost/asio/read_at.hpp (27766B)
//
// read_at.hpp
// ~~~~~~~~~~~
//
// Copyright (c) 2003-2020 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_READ_AT_HPP
#define BOOST_ASIO_READ_AT_HPP
#if defined(_MSC_VER) && (_MSC_VER >= 1200)
# pragma once
#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
#include
#include
#include
#include
#include
#if !defined(BOOST_ASIO_NO_EXTENSIONS)
# include
#endif // !defined(BOOST_ASIO_NO_EXTENSIONS)
#include
namespace boost {
namespace asio {
/**
* @defgroup read_at boost::asio::read_at
*
* @brief The @c read_at function is a composed operation that reads a certain
* amount of data at the specified offset before returning.
*/
/*@{*/
/// Attempt to read a certain amount of data at the specified offset before
/// returning.
/**
* This function is used to read a certain number of bytes of data from a
* random access device at the specified offset. The call will block until one
* of the following conditions is true:
*
* @li The supplied buffers are full. 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
* read_some_at function.
*
* @param d The device from which the data is to be read. The type must support
* the SyncRandomAccessReadDevice concept.
*
* @param offset The offset at which the data will be read.
*
* @param buffers One or more buffers into which the data will be read. The sum
* of the buffer sizes indicates the maximum number of bytes to read from the
* device.
*
* @returns The number of bytes transferred.
*
* @throws boost::system::system_error Thrown on failure.
*
* @par Example
* To read into a single data buffer use the @ref buffer function as follows:
* @code boost::asio::read_at(d, 42, boost::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.
*
* @note This overload is equivalent to calling:
* @code boost::asio::read_at(
* d, 42, buffers,
* boost::asio::transfer_all()); @endcode
*/
template
std::size_t read_at(SyncRandomAccessReadDevice& d,
uint64_t offset, const MutableBufferSequence& buffers);
/// Attempt to read a certain amount of data at the specified offset before
/// returning.
/**
* This function is used to read a certain number of bytes of data from a
* random access device at the specified offset. The call will block until one
* of the following conditions is true:
*
* @li The supplied buffers are full. 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
* read_some_at function.
*
* @param d The device from which the data is to be read. The type must support
* the SyncRandomAccessReadDevice concept.
*
* @param offset The offset at which the data will be read.
*
* @param buffers One or more buffers into which the data will be read. The sum
* of the buffer sizes indicates the maximum number of bytes to read from the
* device.
*
* @param ec Set to indicate what error occurred, if any.
*
* @returns The number of bytes transferred.
*
* @par Example
* To read into a single data buffer use the @ref buffer function as follows:
* @code boost::asio::read_at(d, 42,
* boost::asio::buffer(data, size), ec); @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.
*
* @note This overload is equivalent to calling:
* @code boost::asio::read_at(
* d, 42, buffers,
* boost::asio::transfer_all(), ec); @endcode
*/
template
std::size_t read_at(SyncRandomAccessReadDevice& d,
uint64_t offset, const MutableBufferSequence& buffers,
boost::system::error_code& ec);
/// Attempt to read a certain amount of data at the specified offset before
/// returning.
/**
* This function is used to read a certain number of bytes of data from a
* random access device at the specified offset. The call will block until one
* of the following conditions is true:
*
* @li The supplied buffers are full. 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
* read_some_at function.
*
* @param d The device from which the data is to be read. The type must support
* the SyncRandomAccessReadDevice concept.
*
* @param offset The offset at which the data will be read.
*
* @param buffers One or more buffers into which the data will be read. The sum
* of the buffer sizes indicates the maximum number of bytes to read from the
* device.
*
* @param completion_condition The function object to be called to determine
* whether the read operation is complete. The signature of the function object
* must be:
* @code std::size_t completion_condition(
* // Result of latest read_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 read operation is complete. A non-zero
* return value indicates the maximum number of bytes to be read on the next
* call to the device's read_some_at function.
*
* @returns The number of bytes transferred.
*
* @throws boost::system::system_error Thrown on failure.
*
* @par Example
* To read into a single data buffer use the @ref buffer function as follows:
* @code boost::asio::read_at(d, 42, boost::asio::buffer(data, size),
* boost::asio::transfer_at_least(32)); @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
std::size_t read_at(SyncRandomAccessReadDevice& d,
uint64_t offset, const MutableBufferSequence& buffers,
CompletionCondition completion_condition);
/// Attempt to read a certain amount of data at the specified offset before
/// returning.
/**
* This function is used to read a certain number of bytes of data from a
* random access device at the specified offset. The call will block until one
* of the following conditions is true:
*
* @li The supplied buffers are full. 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
* read_some_at function.
*
* @param d The device from which the data is to be read. The type must support
* the SyncRandomAccessReadDevice concept.
*
* @param offset The offset at which the data will be read.
*
* @param buffers One or more buffers into which the data will be read. The sum
* of the buffer sizes indicates the maximum number of bytes to read from the
* device.
*
* @param completion_condition The function object to be called to determine
* whether the read operation is complete. The signature of the function object
* must be:
* @code std::size_t completion_condition(
* // Result of latest read_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 read operation is complete. A non-zero
* return value indicates the maximum number of bytes to be read on the next
* call to the device's read_some_at function.
*
* @param ec Set to indicate what error occurred, if any.
*
* @returns The number of bytes read. If an error occurs, returns the total
* number of bytes successfully transferred prior to the error.
*/
template
std::size_t read_at(SyncRandomAccessReadDevice& d,
uint64_t offset, const MutableBufferSequence& buffers,
CompletionCondition completion_condition, boost::system::error_code& ec);
#if !defined(BOOST_ASIO_NO_EXTENSIONS)
#if !defined(BOOST_ASIO_NO_IOSTREAM)
/// Attempt to read a certain amount of data at the specified offset before
/// returning.
/**
* This function is used to read a certain number of bytes of data from a
* random access device at the specified offset. The call will block until one
* of the following conditions is true:
*
* @li An error occurred.
*
* This operation is implemented in terms of zero or more calls to the device's
* read_some_at function.
*
* @param d The device from which the data is to be read. The type must support
* the SyncRandomAccessReadDevice concept.
*
* @param offset The offset at which the data will be read.
*
* @param b The basic_streambuf object into which the data will be read.
*
* @returns The number of bytes transferred.
*
* @throws boost::system::system_error Thrown on failure.
*
* @note This overload is equivalent to calling:
* @code boost::asio::read_at(
* d, 42, b,
* boost::asio::transfer_all()); @endcode
*/
template
std::size_t read_at(SyncRandomAccessReadDevice& d,
uint64_t offset, basic_streambuf& b);
/// Attempt to read a certain amount of data at the specified offset before
/// returning.
/**
* This function is used to read a certain number of bytes of data from a
* random access device at the specified offset. The call will block until one
* of the following conditions is true:
*
* @li An error occurred.
*
* This operation is implemented in terms of zero or more calls to the device's
* read_some_at function.
*
* @param d The device from which the data is to be read. The type must support
* the SyncRandomAccessReadDevice concept.
*
* @param offset The offset at which the data will be read.
*
* @param b The basic_streambuf object into which the data will be read.
*
* @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::read_at(
* d, 42, b,
* boost::asio::transfer_all(), ec); @endcode
*/
template
std::size_t read_at(SyncRandomAccessReadDevice& d,
uint64_t offset, basic_streambuf& b,
boost::system::error_code& ec);
/// Attempt to read a certain amount of data at the specified offset before
/// returning.
/**
* This function is used to read a certain number of bytes of data from a
* random access device at the specified offset. The call will block until one
* of the following conditions is true:
*
* @li The completion_condition function object returns 0.
*
* This operation is implemented in terms of zero or more calls to the device's
* read_some_at function.
*
* @param d The device from which the data is to be read. The type must support
* the SyncRandomAccessReadDevice concept.
*
* @param offset The offset at which the data will be read.
*
* @param b The basic_streambuf object into which the data will be read.
*
* @param completion_condition The function object to be called to determine
* whether the read operation is complete. The signature of the function object
* must be:
* @code std::size_t completion_condition(
* // Result of latest read_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 read operation is complete. A non-zero
* return value indicates the maximum number of bytes to be read on the next
* call to the device's read_some_at function.
*
* @returns The number of bytes transferred.
*
* @throws boost::system::system_error Thrown on failure.
*/
template
std::size_t read_at(SyncRandomAccessReadDevice& d,
uint64_t offset, basic_streambuf& b,
CompletionCondition completion_condition);
/// Attempt to read a certain amount of data at the specified offset before
/// returning.
/**
* This function is used to read a certain number of bytes of data from a
* random access device at the specified offset. The call will block until one
* of the following conditions is true:
*
* @li The completion_condition function object returns 0.
*
* This operation is implemented in terms of zero or more calls to the device's
* read_some_at function.
*
* @param d The device from which the data is to be read. The type must support
* the SyncRandomAccessReadDevice concept.
*
* @param offset The offset at which the data will be read.
*
* @param b The basic_streambuf object into which the data will be read.
*
* @param completion_condition The function object to be called to determine
* whether the read operation is complete. The signature of the function object
* must be:
* @code std::size_t completion_condition(
* // Result of latest read_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 read operation is complete. A non-zero
* return value indicates the maximum number of bytes to be read on the next
* call to the device's read_some_at function.
*
* @param ec Set to indicate what error occurred, if any.
*
* @returns The number of bytes read. If an error occurs, returns the total
* number of bytes successfully transferred prior to the error.
*/
template
std::size_t read_at(SyncRandomAccessReadDevice& d,
uint64_t offset, basic_streambuf& b,
CompletionCondition completion_condition, boost::system::error_code& ec);
#endif // !defined(BOOST_ASIO_NO_IOSTREAM)
#endif // !defined(BOOST_ASIO_NO_EXTENSIONS)
/*@}*/
/**
* @defgroup async_read_at boost::asio::async_read_at
*
* @brief The @c async_read_at function is a composed asynchronous operation
* that reads a certain amount of data at the specified offset.
*/
/*@{*/
/// Start an asynchronous operation to read a certain amount of data at the
/// specified offset.
/**
* This function is used to asynchronously read a certain number of bytes of
* data from a random access device at the specified offset. The function call
* always returns immediately. The asynchronous operation will continue until
* one of the following conditions is true:
*
* @li The supplied buffers are full. 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_read_some_at function.
*
* @param d The device from which the data is to be read. The type must support
* the AsyncRandomAccessReadDevice concept.
*
* @param offset The offset at which the data will be read.
*
* @param buffers One or more buffers into which the data will be read. The sum
* of the buffer sizes indicates the maximum number of bytes to read from the
* device. 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(
* // Result of operation.
* const boost::system::error_code& error,
*
* // Number of bytes copied into the buffers. If an error
* // occurred, this will be the number of bytes successfully
* // transferred prior to the error.
* 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 read into a single data buffer use the @ref buffer function as follows:
* @code
* boost::asio::async_read_at(d, 42, boost::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.
*
* @note This overload is equivalent to calling:
* @code boost::asio::async_read_at(
* d, 42, buffers,
* boost::asio::transfer_all(),
* handler); @endcode
*/
template
BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
void (boost::system::error_code, std::size_t))
async_read_at(AsyncRandomAccessReadDevice& d, uint64_t offset,
const MutableBufferSequence& buffers,
BOOST_ASIO_MOVE_ARG(ReadHandler) handler
BOOST_ASIO_DEFAULT_COMPLETION_TOKEN(
typename AsyncRandomAccessReadDevice::executor_type));
/// Start an asynchronous operation to read a certain amount of data at the
/// specified offset.
/**
* This function is used to asynchronously read a certain number of bytes of
* data from a random access device at the specified offset. The function call
* always returns immediately. The asynchronous operation will continue until
* one of the following conditions is true:
*
* @li The supplied buffers are full. That is, the bytes transferred is equal to
* the sum of the buffer sizes.
*
* @li The completion_condition function object returns 0.
*
* @param d The device from which the data is to be read. The type must support
* the AsyncRandomAccessReadDevice concept.
*
* @param offset The offset at which the data will be read.
*
* @param buffers One or more buffers into which the data will be read. The sum
* of the buffer sizes indicates the maximum number of bytes to read from the
* device. 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 read operation is complete. The signature of the function object
* must be:
* @code std::size_t completion_condition(
* // Result of latest async_read_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 read operation is complete. A non-zero
* return value indicates the maximum number of bytes to be read on the next
* call to the device's async_read_some_at function.
*
* @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(
* // Result of operation.
* const boost::system::error_code& error,
*
* // Number of bytes copied into the buffers. If an error
* // occurred, this will be the number of bytes successfully
* // transferred prior to the error.
* 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 read into a single data buffer use the @ref buffer function as follows:
* @code boost::asio::async_read_at(d, 42,
* boost::asio::buffer(data, size),
* boost::asio::transfer_at_least(32),
* 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
BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
void (boost::system::error_code, std::size_t))
async_read_at(AsyncRandomAccessReadDevice& d,
uint64_t offset, const MutableBufferSequence& buffers,
CompletionCondition completion_condition,
BOOST_ASIO_MOVE_ARG(ReadHandler) handler
BOOST_ASIO_DEFAULT_COMPLETION_TOKEN(
typename AsyncRandomAccessReadDevice::executor_type));
#if !defined(BOOST_ASIO_NO_EXTENSIONS)
#if !defined(BOOST_ASIO_NO_IOSTREAM)
/// Start an asynchronous operation to read a certain amount of data at the
/// specified offset.
/**
* This function is used to asynchronously read a certain number of bytes of
* data from a random access device at the specified offset. The function call
* always returns immediately. The asynchronous operation will continue until
* one of the following conditions is true:
*
* @li An error occurred.
*
* This operation is implemented in terms of zero or more calls to the device's
* async_read_some_at function.
*
* @param d The device from which the data is to be read. The type must support
* the AsyncRandomAccessReadDevice concept.
*
* @param offset The offset at which the data will be read.
*
* @param b A basic_streambuf object into which the data will be read. 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 read 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 copied into the buffers. If an error
* // occurred, this will be the number of bytes successfully
* // transferred prior to the error.
* 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().
*
* @note This overload is equivalent to calling:
* @code boost::asio::async_read_at(
* d, 42, b,
* boost::asio::transfer_all(),
* handler); @endcode
*/
template
BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
void (boost::system::error_code, std::size_t))
async_read_at(AsyncRandomAccessReadDevice& d,
uint64_t offset, basic_streambuf& b,
BOOST_ASIO_MOVE_ARG(ReadHandler) handler
BOOST_ASIO_DEFAULT_COMPLETION_TOKEN(
typename AsyncRandomAccessReadDevice::executor_type));
/// Start an asynchronous operation to read a certain amount of data at the
/// specified offset.
/**
* This function is used to asynchronously read a certain number of bytes of
* data from a random access device at the specified offset. The function call
* always returns immediately. The asynchronous operation will continue until
* one of the following conditions is true:
*
* @li The completion_condition function object returns 0.
*
* This operation is implemented in terms of zero or more calls to the device's
* async_read_some_at function.
*
* @param d The device from which the data is to be read. The type must support
* the AsyncRandomAccessReadDevice concept.
*
* @param offset The offset at which the data will be read.
*
* @param b A basic_streambuf object into which the data will be read. 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 read operation is complete. The signature of the function object
* must be:
* @code std::size_t completion_condition(
* // Result of latest async_read_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 read operation is complete. A non-zero
* return value indicates the maximum number of bytes to be read on the next
* call to the device's async_read_some_at function.
*
* @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(
* // Result of operation.
* const boost::system::error_code& error,
*
* // Number of bytes copied into the buffers. If an error
* // occurred, this will be the number of bytes successfully
* // transferred prior to the error.
* 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
BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
void (boost::system::error_code, std::size_t))
async_read_at(AsyncRandomAccessReadDevice& d,
uint64_t offset, basic_streambuf& b,
CompletionCondition completion_condition,
BOOST_ASIO_MOVE_ARG(ReadHandler) handler
BOOST_ASIO_DEFAULT_COMPLETION_TOKEN(
typename AsyncRandomAccessReadDevice::executor_type));
#endif // !defined(BOOST_ASIO_NO_IOSTREAM)
#endif // !defined(BOOST_ASIO_NO_EXTENSIONS)
/*@}*/
} // namespace asio
} // namespace boost
#include
#include
#endif // BOOST_ASIO_READ_AT_HPP