//
// read.hpp
// ~~~~~~~~
//
// Copyright (c) 2003-2011 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_HPP
#define BOOST_ASIO_READ_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/basic_streambuf_fwd.hpp>
#include <boost/asio/error.hpp>
#include <boost/asio/detail/push_options.hpp>
namespace boost {
namespace asio {
/**
* @defgroup read boost::asio::read
*
* @brief Attempt to read a certain amount of data from a stream before
* returning.
*/
/*@{*/
/// 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 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 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 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
* stream.
*
* @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(s, 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(
* s, buffers,
* boost::asio::transfer_all()); @endcode
*/
template <typename SyncReadStream, typename MutableBufferSequence>
std::size_t read(SyncReadStream& s, const MutableBufferSequence& buffers);
/// 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 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 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 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
* stream.
*
* @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(s, 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(
* s, buffers,
* boost::asio::transfer_all(), ec); @endcode
*/
template <typename SyncReadStream, typename MutableBufferSequence>
std::size_t read(SyncReadStream& s, const MutableBufferSequence& buffers,
boost::system::error_code& ec);
/// 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 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 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 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
* stream.
*
* @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 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 stream's read_some 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(s, 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 <typename SyncReadStream, typename MutableBufferSequence,
typename CompletionCondition>
std::size_t read(SyncReadStream& s, const MutableBufferSequence& buffers,
CompletionCondition completion_condition);
/// 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 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 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 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
* stream.
*
* @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 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 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 MutableBufferSequence,
typename CompletionCondition>
std::size_t read(SyncReadStream& s, const MutableBufferSequence& buffers,
CompletionCondition completion_condition, boost::system::error_code& ec);
#if !defined(BOOST_NO_IOSTREAM)
/// 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 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 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(
* s, b,
* boost::asio::transfer_all()); @endcode
*/
template <typename SyncReadStream, typename Allocator>
std::size_t read(SyncReadStream& s, basic_streambuf<Allocator>& b);
/// 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 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 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(
* s, b,
* boost::asio::transfer_all(), ec); @endcode
*/
template <typename SyncReadStream, typename Allocator>
std::size_t read(SyncReadStream& s, basic_streambuf<Allocator>& b,
boost::system::error_code& ec);
/// 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 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 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 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 stream's read_some function.
*
* @returns The number of bytes transferred.
*
* @throws boost::system::system_error Thrown on failure.
*/
template <typename SyncReadStream, typename Allocator,
typename CompletionCondition>
std::size_t read(SyncReadStream& s, basic_streambuf<Allocator>& b,
CompletionCondition completion_condition);
/// 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 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 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 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 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 Allocator,
typename CompletionCondition>
std::size_t read(SyncReadStream& s, basic_streambuf<Allocator>& b,
CompletionCondition completion_condition, boost::system::error_code& ec);
#endif // !defined(BOOST_NO_IOSTREAM)
/*@}*/
/**
* @defgroup async_read boost::asio::async_read
*
* @brief Start an asynchronous operation to read a certain amount of data from
* a stream.
*/
/*@{*/
/// 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 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 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 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
* stream. 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 boost::system::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. Invocation of
* the handler will be performed in a manner equivalent to using
* boost::asio::io_service::post().
*
* @par Example
* To read into a single data buffer use the @ref buffer function as follows:
* @code
* boost::asio::async_read(s, 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(
* s, buffers,
* boost::asio::transfer_all(),
* handler); @endcode
*/
template <typename AsyncReadStream, typename MutableBufferSequence,
typename ReadHandler>
void async_read(AsyncReadStream& s, const MutableBufferSequence& buffers,
BOOST_ASIO_MOVE_ARG(ReadHandler) handler);
/// 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 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 s The stream from which the data is to be read. The type must support
* the AsyncReadStream concept.
*
* @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
* stream. 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 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 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 boost::system::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. Invocation of
* the handler will be performed in a manner equivalent to using
* boost::asio::io_service::post().
*
* @par Example
* To read into a single data buffer use the @ref buffer function as follows:
* @code boost::asio::async_read(s,
* 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 <typename AsyncReadStream, typename MutableBufferSequence,
typename CompletionCondition, typename ReadHandler>
void async_read(AsyncReadStream& s, const MutableBufferSequence& buffers,
CompletionCondition completion_condition,
BOOST_ASIO_MOVE_ARG(ReadHandler) handler);
#if !defined(BOOST_NO_IOSTREAM)
/// 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 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 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(
* const boost::system::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. Invocation of
* the handler will be performed in a manner equivalent to using
* boost::asio::io_service::post().
*
* @note This overload is equivalent to calling:
* @code boost::asio::async_read(
* s, b,
* boost::asio::transfer_all(),
* handler); @endcode
*/
template <typename AsyncReadStream, typename Allocator, typename ReadHandler>
void async_read(AsyncReadStream& s, basic_streambuf<Allocator>& b,
BOOST_ASIO_MOVE_ARG(ReadHandler) handler);
/// 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 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 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 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 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 boost::system::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. Invocation of
* the handler will be performed in a manner equivalent to using
* boost::asio::io_service::post().
*/
template <typename AsyncReadStream, typename Allocator,
typename CompletionCondition, typename ReadHandler>
void async_read(AsyncReadStream& s, basic_streambuf<Allocator>& b,
CompletionCondition completion_condition,
BOOST_ASIO_MOVE_ARG(ReadHandler) handler);
#endif // !defined(BOOST_NO_IOSTREAM)
/*@}*/
} // namespace asio
} // namespace boost
#include <boost/asio/detail/pop_options.hpp>
#include <boost/asio/impl/read.hpp>
#endif // BOOST_ASIO_READ_HPP
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