diff options
Diffstat (limited to '3rdparty/asio/include/asio/read.hpp')
-rw-r--r-- | 3rdparty/asio/include/asio/read.hpp | 611 |
1 files changed, 526 insertions, 85 deletions
diff --git a/3rdparty/asio/include/asio/read.hpp b/3rdparty/asio/include/asio/read.hpp index 4839934dbab..3d666adb8d3 100644 --- a/3rdparty/asio/include/asio/read.hpp +++ b/3rdparty/asio/include/asio/read.hpp @@ -2,7 +2,7 @@ // read.hpp // ~~~~~~~~ // -// Copyright (c) 2003-2016 Christopher M. Kohlhoff (chris at kohlhoff dot com) +// Copyright (c) 2003-2021 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) @@ -32,8 +32,8 @@ namespace asio { /** * @defgroup read asio::read * - * @brief Attempt to read a certain amount of data from a stream before - * returning. + * @brief The @c read function is a composed operation that reads a certain + * amount of data from a stream before returning. */ /*@{*/ @@ -75,9 +75,9 @@ namespace asio { */ template <typename SyncReadStream, typename MutableBufferSequence> std::size_t read(SyncReadStream& s, const MutableBufferSequence& buffers, - typename enable_if< + typename constraint< is_mutable_buffer_sequence<MutableBufferSequence>::value - >::type* = 0); + >::type = 0); /// Attempt to read a certain amount of data from a stream before returning. /** @@ -118,9 +118,9 @@ std::size_t read(SyncReadStream& s, const MutableBufferSequence& buffers, template <typename SyncReadStream, typename MutableBufferSequence> std::size_t read(SyncReadStream& s, const MutableBufferSequence& buffers, asio::error_code& ec, - typename enable_if< + typename constraint< is_mutable_buffer_sequence<MutableBufferSequence>::value - >::type* = 0); + >::type = 0); /// Attempt to read a certain amount of data from a stream before returning. /** @@ -172,9 +172,9 @@ template <typename SyncReadStream, typename MutableBufferSequence, typename CompletionCondition> std::size_t read(SyncReadStream& s, const MutableBufferSequence& buffers, CompletionCondition completion_condition, - typename enable_if< + typename constraint< is_mutable_buffer_sequence<MutableBufferSequence>::value - >::type* = 0); + >::type = 0); /// Attempt to read a certain amount of data from a stream before returning. /** @@ -219,9 +219,11 @@ template <typename SyncReadStream, typename MutableBufferSequence, typename CompletionCondition> std::size_t read(SyncReadStream& s, const MutableBufferSequence& buffers, CompletionCondition completion_condition, asio::error_code& ec, - typename enable_if< + typename constraint< is_mutable_buffer_sequence<MutableBufferSequence>::value - >::type* = 0); + >::type = 0); + +#if !defined(ASIO_NO_DYNAMIC_BUFFER_V1) /// Attempt to read a certain amount of data from a stream before returning. /** @@ -250,12 +252,15 @@ std::size_t read(SyncReadStream& s, const MutableBufferSequence& buffers, * s, buffers, * asio::transfer_all()); @endcode */ -template <typename SyncReadStream, typename DynamicBuffer> +template <typename SyncReadStream, typename DynamicBuffer_v1> std::size_t read(SyncReadStream& s, - ASIO_MOVE_ARG(DynamicBuffer) buffers, - typename enable_if< - is_dynamic_buffer<DynamicBuffer>::value - >::type* = 0); + ASIO_MOVE_ARG(DynamicBuffer_v1) buffers, + typename constraint< + is_dynamic_buffer_v1<typename decay<DynamicBuffer_v1>::type>::value + >::type = 0, + typename constraint< + !is_dynamic_buffer_v2<typename decay<DynamicBuffer_v1>::type>::value + >::type = 0); /// Attempt to read a certain amount of data from a stream before returning. /** @@ -283,13 +288,16 @@ std::size_t read(SyncReadStream& s, * s, buffers, * asio::transfer_all(), ec); @endcode */ -template <typename SyncReadStream, typename DynamicBuffer> +template <typename SyncReadStream, typename DynamicBuffer_v1> std::size_t read(SyncReadStream& s, - ASIO_MOVE_ARG(DynamicBuffer) buffers, + ASIO_MOVE_ARG(DynamicBuffer_v1) buffers, asio::error_code& ec, - typename enable_if< - is_dynamic_buffer<DynamicBuffer>::value - >::type* = 0); + typename constraint< + is_dynamic_buffer_v1<typename decay<DynamicBuffer_v1>::type>::value + >::type = 0, + typename constraint< + !is_dynamic_buffer_v2<typename decay<DynamicBuffer_v1>::type>::value + >::type = 0); /// Attempt to read a certain amount of data from a stream before returning. /** @@ -327,14 +335,17 @@ std::size_t read(SyncReadStream& s, * * @throws asio::system_error Thrown on failure. */ -template <typename SyncReadStream, typename DynamicBuffer, +template <typename SyncReadStream, typename DynamicBuffer_v1, typename CompletionCondition> std::size_t read(SyncReadStream& s, - ASIO_MOVE_ARG(DynamicBuffer) buffers, + ASIO_MOVE_ARG(DynamicBuffer_v1) buffers, CompletionCondition completion_condition, - typename enable_if< - is_dynamic_buffer<DynamicBuffer>::value - >::type* = 0); + typename constraint< + is_dynamic_buffer_v1<typename decay<DynamicBuffer_v1>::type>::value + >::type = 0, + typename constraint< + !is_dynamic_buffer_v2<typename decay<DynamicBuffer_v1>::type>::value + >::type = 0); /// Attempt to read a certain amount of data from a stream before returning. /** @@ -373,14 +384,17 @@ std::size_t read(SyncReadStream& s, * @returns The number of bytes read. If an error occurs, returns the total * number of bytes successfully transferred prior to the error. */ -template <typename SyncReadStream, typename DynamicBuffer, +template <typename SyncReadStream, typename DynamicBuffer_v1, typename CompletionCondition> std::size_t read(SyncReadStream& s, - ASIO_MOVE_ARG(DynamicBuffer) buffers, + ASIO_MOVE_ARG(DynamicBuffer_v1) buffers, CompletionCondition completion_condition, asio::error_code& ec, - typename enable_if< - is_dynamic_buffer<DynamicBuffer>::value - >::type* = 0); + typename constraint< + is_dynamic_buffer_v1<typename decay<DynamicBuffer_v1>::type>::value + >::type = 0, + typename constraint< + !is_dynamic_buffer_v2<typename decay<DynamicBuffer_v1>::type>::value + >::type = 0); #if !defined(ASIO_NO_EXTENSIONS) #if !defined(ASIO_NO_IOSTREAM) @@ -527,13 +541,169 @@ std::size_t read(SyncReadStream& s, basic_streambuf<Allocator>& b, #endif // !defined(ASIO_NO_IOSTREAM) #endif // !defined(ASIO_NO_EXTENSIONS) +#endif // !defined(ASIO_NO_DYNAMIC_BUFFER_V1) + +/// Attempt to read a certain amount of data from a stream before returning. +/** + * This function is used to read a certain number of bytes of data from a + * stream. The call will block until one of the following conditions is true: + * + * @li The specified dynamic buffer sequence is full (that is, it has reached + * maximum size). + * + * @li An error occurred. + * + * This operation is implemented in terms of zero or more calls to the stream's + * read_some function. + * + * @param s The stream from which the data is to be read. The type must support + * the SyncReadStream concept. + * + * @param buffers The dynamic buffer sequence into which the data will be read. + * + * @returns The number of bytes transferred. + * + * @throws asio::system_error Thrown on failure. + * + * @note This overload is equivalent to calling: + * @code asio::read( + * s, buffers, + * asio::transfer_all()); @endcode + */ +template <typename SyncReadStream, typename DynamicBuffer_v2> +std::size_t read(SyncReadStream& s, DynamicBuffer_v2 buffers, + typename constraint< + is_dynamic_buffer_v2<DynamicBuffer_v2>::value + >::type = 0); + +/// Attempt to read a certain amount of data from a stream before returning. +/** + * This function is used to read a certain number of bytes of data from a + * stream. The call will block until one of the following conditions is true: + * + * @li The supplied buffer is full (that is, it has reached maximum size). + * + * @li An error occurred. + * + * This operation is implemented in terms of zero or more calls to the stream's + * read_some function. + * + * @param s The stream from which the data is to be read. The type must support + * the SyncReadStream concept. + * + * @param buffers The dynamic buffer sequence 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 asio::read( + * s, buffers, + * asio::transfer_all(), ec); @endcode + */ +template <typename SyncReadStream, typename DynamicBuffer_v2> +std::size_t read(SyncReadStream& s, DynamicBuffer_v2 buffers, + asio::error_code& ec, + typename constraint< + is_dynamic_buffer_v2<DynamicBuffer_v2>::value + >::type = 0); + +/// Attempt to read a certain amount of data from a stream before returning. +/** + * This function is used to read a certain number of bytes of data from a + * stream. The call will block until one of the following conditions is true: + * + * @li The specified dynamic buffer sequence is full (that is, it has reached + * maximum size). + * + * @li The completion_condition function object returns 0. + * + * This operation is implemented in terms of zero or more calls to the stream's + * read_some function. + * + * @param s The stream from which the data is to be read. The type must support + * the SyncReadStream concept. + * + * @param buffers The dynamic buffer sequence 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 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 read operation is complete. A non-zero + * return value indicates the maximum number of bytes to be read on the next + * call to the stream's read_some function. + * + * @returns The number of bytes transferred. + * + * @throws asio::system_error Thrown on failure. + */ +template <typename SyncReadStream, typename DynamicBuffer_v2, + typename CompletionCondition> +std::size_t read(SyncReadStream& s, DynamicBuffer_v2 buffers, + CompletionCondition completion_condition, + typename constraint< + is_dynamic_buffer_v2<DynamicBuffer_v2>::value + >::type = 0); + +/// Attempt to read a certain amount of data from a stream before returning. +/** + * This function is used to read a certain number of bytes of data from a + * stream. The call will block until one of the following conditions is true: + * + * @li The specified dynamic buffer sequence is full (that is, it has reached + * maximum size). + * + * @li The completion_condition function object returns 0. + * + * This operation is implemented in terms of zero or more calls to the stream's + * read_some function. + * + * @param s The stream from which the data is to be read. The type must support + * the SyncReadStream concept. + * + * @param buffers The dynamic buffer sequence 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 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 read operation is complete. A non-zero + * return value indicates the maximum number of bytes to be read on the next + * call to the stream's read_some 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 <typename SyncReadStream, typename DynamicBuffer_v2, + typename CompletionCondition> +std::size_t read(SyncReadStream& s, DynamicBuffer_v2 buffers, + CompletionCondition completion_condition, asio::error_code& ec, + typename constraint< + is_dynamic_buffer_v2<DynamicBuffer_v2>::value + >::type = 0); /*@}*/ /** * @defgroup async_read asio::async_read * - * @brief Start an asynchronous operation to read a certain amount of data from - * a stream. + * @brief The @c async_read function is a composed asynchronous operation that + * reads a certain amount of data from a stream before completion. */ /*@{*/ @@ -578,9 +748,9 @@ std::size_t read(SyncReadStream& s, basic_streambuf<Allocator>& b, * // prior to the error. * ); @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(). + * 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 asio::post(). * * @par Example * To read into a single data buffer use the @ref buffer function as follows: @@ -596,16 +766,32 @@ std::size_t read(SyncReadStream& s, basic_streambuf<Allocator>& b, * s, buffers, * asio::transfer_all(), * handler); @endcode + * + * @par Per-Operation Cancellation + * This asynchronous operation supports cancellation for the following + * asio::cancellation_type values: + * + * @li @c cancellation_type::terminal + * + * @li @c cancellation_type::partial + * + * if they are also supported by the @c AsyncReadStream type's + * @c async_read_some operation. */ template <typename AsyncReadStream, typename MutableBufferSequence, - typename ReadHandler> -ASIO_INITFN_RESULT_TYPE(ReadHandler, + ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code, + std::size_t)) ReadHandler + ASIO_DEFAULT_COMPLETION_TOKEN_TYPE( + typename AsyncReadStream::executor_type)> +ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler, void (asio::error_code, std::size_t)) async_read(AsyncReadStream& s, const MutableBufferSequence& buffers, - ASIO_MOVE_ARG(ReadHandler) handler, - typename enable_if< + ASIO_MOVE_ARG(ReadHandler) handler + ASIO_DEFAULT_COMPLETION_TOKEN( + typename AsyncReadStream::executor_type), + typename constraint< is_mutable_buffer_sequence<MutableBufferSequence>::value - >::type* = 0); + >::type = 0); /// Start an asynchronous operation to read a certain amount of data from a /// stream. @@ -656,9 +842,9 @@ async_read(AsyncReadStream& s, const MutableBufferSequence& buffers, * // prior to the error. * ); @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(). + * 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 asio::post(). * * @par Example * To read into a single data buffer use the @ref buffer function as follows: @@ -669,17 +855,36 @@ async_read(AsyncReadStream& s, const MutableBufferSequence& buffers, * 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. + * + * @par Per-Operation Cancellation + * This asynchronous operation supports cancellation for the following + * asio::cancellation_type values: + * + * @li @c cancellation_type::terminal + * + * @li @c cancellation_type::partial + * + * if they are also supported by the @c AsyncReadStream type's + * @c async_read_some operation. */ -template <typename AsyncReadStream, typename MutableBufferSequence, - typename CompletionCondition, typename ReadHandler> -ASIO_INITFN_RESULT_TYPE(ReadHandler, +template <typename AsyncReadStream, + typename MutableBufferSequence, typename CompletionCondition, + ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code, + std::size_t)) ReadHandler + ASIO_DEFAULT_COMPLETION_TOKEN_TYPE( + typename AsyncReadStream::executor_type)> +ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler, void (asio::error_code, std::size_t)) async_read(AsyncReadStream& s, const MutableBufferSequence& buffers, CompletionCondition completion_condition, - ASIO_MOVE_ARG(ReadHandler) handler, - typename enable_if< + ASIO_MOVE_ARG(ReadHandler) handler + ASIO_DEFAULT_COMPLETION_TOKEN( + typename AsyncReadStream::executor_type), + typename constraint< is_mutable_buffer_sequence<MutableBufferSequence>::value - >::type* = 0); + >::type = 0); + +#if !defined(ASIO_NO_DYNAMIC_BUFFER_V1) /// Start an asynchronous operation to read a certain amount of data from a /// stream. @@ -721,26 +926,45 @@ async_read(AsyncReadStream& s, const MutableBufferSequence& buffers, * // prior to the error. * ); @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(). + * 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 asio::post(). * * @note This overload is equivalent to calling: * @code asio::async_read( * s, buffers, * asio::transfer_all(), * handler); @endcode + * + * @par Per-Operation Cancellation + * This asynchronous operation supports cancellation for the following + * asio::cancellation_type values: + * + * @li @c cancellation_type::terminal + * + * @li @c cancellation_type::partial + * + * if they are also supported by the @c AsyncReadStream type's + * @c async_read_some operation. */ -template <typename AsyncReadStream, - typename DynamicBuffer, typename ReadHandler> -ASIO_INITFN_RESULT_TYPE(ReadHandler, +template <typename AsyncReadStream, typename DynamicBuffer_v1, + ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code, + std::size_t)) ReadHandler + ASIO_DEFAULT_COMPLETION_TOKEN_TYPE( + typename AsyncReadStream::executor_type)> +ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler, void (asio::error_code, std::size_t)) async_read(AsyncReadStream& s, - ASIO_MOVE_ARG(DynamicBuffer) buffers, - ASIO_MOVE_ARG(ReadHandler) handler, - typename enable_if< - is_dynamic_buffer<DynamicBuffer>::value - >::type* = 0); + ASIO_MOVE_ARG(DynamicBuffer_v1) buffers, + ASIO_MOVE_ARG(ReadHandler) handler + ASIO_DEFAULT_COMPLETION_TOKEN( + typename AsyncReadStream::executor_type), + typename constraint< + is_dynamic_buffer_v1<typename decay<DynamicBuffer_v1>::type>::value + >::type = 0, + typename constraint< + !is_dynamic_buffer_v2<typename decay<DynamicBuffer_v1>::type>::value + >::type = 0); /// Start an asynchronous operation to read a certain amount of data from a /// stream. @@ -796,21 +1020,41 @@ async_read(AsyncReadStream& s, * // prior to the error. * ); @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(). + * 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 asio::post(). + * + * @par Per-Operation Cancellation + * This asynchronous operation supports cancellation for the following + * asio::cancellation_type values: + * + * @li @c cancellation_type::terminal + * + * @li @c cancellation_type::partial + * + * if they are also supported by the @c AsyncReadStream type's + * @c async_read_some operation. */ -template <typename AsyncReadStream, typename DynamicBuffer, - typename CompletionCondition, typename ReadHandler> -ASIO_INITFN_RESULT_TYPE(ReadHandler, +template <typename AsyncReadStream, + typename DynamicBuffer_v1, typename CompletionCondition, + ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code, + std::size_t)) ReadHandler + ASIO_DEFAULT_COMPLETION_TOKEN_TYPE( + typename AsyncReadStream::executor_type)> +ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler, void (asio::error_code, std::size_t)) async_read(AsyncReadStream& s, - ASIO_MOVE_ARG(DynamicBuffer) buffers, + ASIO_MOVE_ARG(DynamicBuffer_v1) buffers, CompletionCondition completion_condition, - ASIO_MOVE_ARG(ReadHandler) handler, - typename enable_if< - is_dynamic_buffer<DynamicBuffer>::value - >::type* = 0); + ASIO_MOVE_ARG(ReadHandler) handler + ASIO_DEFAULT_COMPLETION_TOKEN( + typename AsyncReadStream::executor_type), + typename constraint< + is_dynamic_buffer_v1<typename decay<DynamicBuffer_v1>::type>::value + >::type = 0, + typename constraint< + !is_dynamic_buffer_v2<typename decay<DynamicBuffer_v1>::type>::value + >::type = 0); #if !defined(ASIO_NO_EXTENSIONS) #if !defined(ASIO_NO_IOSTREAM) @@ -853,21 +1097,38 @@ async_read(AsyncReadStream& s, * // prior to the error. * ); @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(). + * 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 asio::post(). * * @note This overload is equivalent to calling: * @code asio::async_read( * s, b, * asio::transfer_all(), * handler); @endcode + * + * @par Per-Operation Cancellation + * This asynchronous operation supports cancellation for the following + * asio::cancellation_type values: + * + * @li @c cancellation_type::terminal + * + * @li @c cancellation_type::partial + * + * if they are also supported by the @c AsyncReadStream type's + * @c async_read_some operation. */ -template <typename AsyncReadStream, typename Allocator, typename ReadHandler> -ASIO_INITFN_RESULT_TYPE(ReadHandler, +template <typename AsyncReadStream, typename Allocator, + ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code, + std::size_t)) ReadHandler + ASIO_DEFAULT_COMPLETION_TOKEN_TYPE( + typename AsyncReadStream::executor_type)> +ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler, void (asio::error_code, std::size_t)) async_read(AsyncReadStream& s, basic_streambuf<Allocator>& b, - ASIO_MOVE_ARG(ReadHandler) handler); + ASIO_MOVE_ARG(ReadHandler) handler + ASIO_DEFAULT_COMPLETION_TOKEN( + typename AsyncReadStream::executor_type)); /// Start an asynchronous operation to read a certain amount of data from a /// stream. @@ -921,20 +1182,200 @@ async_read(AsyncReadStream& s, basic_streambuf<Allocator>& b, * // prior to the error. * ); @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(). + * 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 asio::post(). + * + * @par Per-Operation Cancellation + * This asynchronous operation supports cancellation for the following + * asio::cancellation_type values: + * + * @li @c cancellation_type::terminal + * + * @li @c cancellation_type::partial + * + * if they are also supported by the @c AsyncReadStream type's + * @c async_read_some operation. */ -template <typename AsyncReadStream, typename Allocator, - typename CompletionCondition, typename ReadHandler> -ASIO_INITFN_RESULT_TYPE(ReadHandler, +template <typename AsyncReadStream, + typename Allocator, typename CompletionCondition, + ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code, + std::size_t)) ReadHandler + ASIO_DEFAULT_COMPLETION_TOKEN_TYPE( + typename AsyncReadStream::executor_type)> +ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler, void (asio::error_code, std::size_t)) async_read(AsyncReadStream& s, basic_streambuf<Allocator>& b, CompletionCondition completion_condition, - ASIO_MOVE_ARG(ReadHandler) handler); + ASIO_MOVE_ARG(ReadHandler) handler + ASIO_DEFAULT_COMPLETION_TOKEN( + typename AsyncReadStream::executor_type)); #endif // !defined(ASIO_NO_IOSTREAM) #endif // !defined(ASIO_NO_EXTENSIONS) +#endif // !defined(ASIO_NO_DYNAMIC_BUFFER_V1) + +/// Start an asynchronous operation to read a certain amount of data from a +/// stream. +/** + * This function is used to asynchronously read a certain number of bytes of + * data from a stream. The function call always returns immediately. The + * asynchronous operation will continue until one of the following conditions is + * true: + * + * @li The specified dynamic buffer sequence is full (that is, it has reached + * maximum size). + * + * @li An error occurred. + * + * This operation is implemented in terms of zero or more calls to the stream's + * async_read_some function, and is known as a <em>composed operation</em>. The + * program must ensure that the stream performs no other read operations (such + * as async_read, the stream's async_read_some function, or any other composed + * operations that perform reads) until this operation completes. + * + * @param s The stream from which the data is to be read. The type must support + * the AsyncReadStream concept. + * + * @param buffers The dynamic buffer sequence into which the data will be read. + * Although the buffers object may be copied as necessary, ownership of the + * underlying memory blocks is retained by the caller, which must guarantee + * that they remain valid until the handler is called. + * + * @param handler The handler to be called when the read operation completes. + * Copies will be made of the handler as required. The function signature of the + * handler must be: + * @code void handler( + * const asio::error_code& error, // Result of operation. + * + * std::size_t bytes_transferred // Number of bytes copied into the + * // buffers. If an error occurred, + * // this will be the number of + * // bytes successfully transferred + * // prior to the error. + * ); @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 asio::post(). + * + * @note This overload is equivalent to calling: + * @code asio::async_read( + * s, buffers, + * asio::transfer_all(), + * handler); @endcode + * + * @par Per-Operation Cancellation + * This asynchronous operation supports cancellation for the following + * asio::cancellation_type values: + * + * @li @c cancellation_type::terminal + * + * @li @c cancellation_type::partial + * + * if they are also supported by the @c AsyncReadStream type's + * @c async_read_some operation. + */ +template <typename AsyncReadStream, typename DynamicBuffer_v2, + ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code, + std::size_t)) ReadHandler + ASIO_DEFAULT_COMPLETION_TOKEN_TYPE( + typename AsyncReadStream::executor_type)> +ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler, + void (asio::error_code, std::size_t)) +async_read(AsyncReadStream& s, DynamicBuffer_v2 buffers, + ASIO_MOVE_ARG(ReadHandler) handler + ASIO_DEFAULT_COMPLETION_TOKEN( + typename AsyncReadStream::executor_type), + typename constraint< + is_dynamic_buffer_v2<DynamicBuffer_v2>::value + >::type = 0); + +/// Start an asynchronous operation to read a certain amount of data from a +/// stream. +/** + * This function is used to asynchronously read a certain number of bytes of + * data from a stream. The function call always returns immediately. The + * asynchronous operation will continue until one of the following conditions is + * true: + * + * @li The specified dynamic buffer sequence is full (that is, it has reached + * maximum size). + * + * @li The completion_condition function object returns 0. + * + * This operation is implemented in terms of zero or more calls to the stream's + * async_read_some function, and is known as a <em>composed operation</em>. The + * program must ensure that the stream performs no other read operations (such + * as async_read, the stream's async_read_some function, or any other composed + * operations that perform reads) until this operation completes. + * + * @param s The stream from which the data is to be read. The type must support + * the AsyncReadStream concept. + * + * @param buffers The dynamic buffer sequence into which the data will be read. + * Although the buffers object may be copied as necessary, ownership of the + * underlying memory blocks is retained by the caller, which must guarantee + * that they remain valid until the handler is called. + * + * @param 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 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 read operation is complete. A non-zero + * return value indicates the maximum number of bytes to be read on the next + * call to the stream's async_read_some 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( + * const asio::error_code& error, // Result of operation. + * + * std::size_t bytes_transferred // Number of bytes copied into the + * // buffers. If an error occurred, + * // this will be the number of + * // bytes successfully transferred + * // prior to the error. + * ); @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 asio::post(). + * + * @par Per-Operation Cancellation + * This asynchronous operation supports cancellation for the following + * asio::cancellation_type values: + * + * @li @c cancellation_type::terminal + * + * @li @c cancellation_type::partial + * + * if they are also supported by the @c AsyncReadStream type's + * @c async_read_some operation. + */ +template <typename AsyncReadStream, + typename DynamicBuffer_v2, typename CompletionCondition, + ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code, + std::size_t)) ReadHandler + ASIO_DEFAULT_COMPLETION_TOKEN_TYPE( + typename AsyncReadStream::executor_type)> +ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler, + void (asio::error_code, std::size_t)) +async_read(AsyncReadStream& s, DynamicBuffer_v2 buffers, + CompletionCondition completion_condition, + ASIO_MOVE_ARG(ReadHandler) handler + ASIO_DEFAULT_COMPLETION_TOKEN( + typename AsyncReadStream::executor_type), + typename constraint< + is_dynamic_buffer_v2<DynamicBuffer_v2>::value + >::type = 0); /*@}*/ |