deluge/library/include/libtorrent/asio/basic_stream_socket.hpp

817 lines
32 KiB
C++

//
// basic_stream_socket.hpp
// ~~~~~~~~~~~~~~~~~~~~~~~
//
// Copyright (c) 2003-2006 Christopher M. Kohlhoff (chris at kohlhoff dot com)
//
// Distributed under the Boost Software License, Version 1.0. (See accompanying
// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
//
#ifndef ASIO_BASIC_STREAM_SOCKET_HPP
#define ASIO_BASIC_STREAM_SOCKET_HPP
#if defined(_MSC_VER) && (_MSC_VER >= 1200)
# pragma once
#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
#include "asio/detail/push_options.hpp"
#include "asio/detail/push_options.hpp"
#include <cstddef>
#include <boost/config.hpp>
#include "asio/detail/pop_options.hpp"
#include "asio/basic_socket.hpp"
#include "asio/error_handler.hpp"
#include "asio/stream_socket_service.hpp"
namespace asio {
/// Provides stream-oriented socket functionality.
/**
* The basic_stream_socket class template provides asynchronous and blocking
* stream-oriented socket functionality.
*
* @par Thread Safety:
* @e Distinct @e objects: Safe.@n
* @e Shared @e objects: Unsafe.
*
* @par Concepts:
* Async_Read_Stream, Async_Write_Stream, Error_Source, IO_Object, Stream,
* Sync_Read_Stream, Sync_Write_Stream.
*/
template <typename Protocol,
typename Service = stream_socket_service<Protocol> >
class basic_stream_socket
: public basic_socket<Protocol, Service>
{
public:
/// The native representation of a socket.
typedef typename Service::native_type native_type;
/// The protocol type.
typedef Protocol protocol_type;
/// The endpoint type.
typedef typename Protocol::endpoint endpoint_type;
/// Construct a basic_stream_socket without opening it.
/**
* This constructor creates a stream socket without opening it. The socket
* needs to be opened and then connected or accepted before data can be sent
* or received on it.
*
* @param io_service The io_service object that the stream socket will use to
* dispatch handlers for any asynchronous operations performed on the socket.
*/
explicit basic_stream_socket(asio::io_service& io_service)
: basic_socket<Protocol, Service>(io_service)
{
}
/// Construct and open a basic_stream_socket.
/**
* This constructor creates and opens a stream socket. The socket needs to be
* connected or accepted before data can be sent or received on it.
*
* @param io_service The io_service object that the stream socket will use to
* dispatch handlers for any asynchronous operations performed on the socket.
*
* @param protocol An object specifying protocol parameters to be used.
*
* @throws asio::error Thrown on failure.
*/
basic_stream_socket(asio::io_service& io_service,
const protocol_type& protocol)
: basic_socket<Protocol, Service>(io_service, protocol)
{
}
/// Construct a basic_stream_socket, opening it and binding it to the given
/// local endpoint.
/**
* This constructor creates a stream socket and automatically opens it bound
* to the specified endpoint on the local machine. The protocol used is the
* protocol associated with the given endpoint.
*
* @param io_service The io_service object that the stream socket will use to
* dispatch handlers for any asynchronous operations performed on the socket.
*
* @param endpoint An endpoint on the local machine to which the stream
* socket will be bound.
*
* @throws asio::error Thrown on failure.
*/
basic_stream_socket(asio::io_service& io_service,
const endpoint_type& endpoint)
: basic_socket<Protocol, Service>(io_service, endpoint)
{
}
/// Construct a basic_stream_socket on an existing native socket.
/**
* This constructor creates a stream socket object to hold an existing native
* socket.
*
* @param io_service The io_service object that the stream socket will use to
* dispatch handlers for any asynchronous operations performed on the socket.
*
* @param protocol An object specifying protocol parameters to be used.
*
* @param native_socket The new underlying socket implementation.
*
* @throws asio::error Thrown on failure.
*/
basic_stream_socket(asio::io_service& io_service,
const protocol_type& protocol, const native_type& native_socket)
: basic_socket<Protocol, Service>(io_service, protocol, native_socket)
{
}
/// Send some data on the socket.
/**
* This function is used to send data on the stream socket. The function
* call will block until one or more bytes of the data has been sent
* successfully, or an until error occurs.
*
* @param buffers One or more data buffers to be sent on the socket.
*
* @returns The number of bytes sent.
*
* @throws asio::error Thrown on failure.
*
* @note The send operation may not transmit all of the data to the peer.
* Consider using the @ref write function if you need to ensure that all data
* is written before the blocking operation completes.
*
* @par Example:
* To send a single data buffer use the @ref buffer function as follows:
* @code
* socket.send(asio::buffer(data, size));
* @endcode
* See the @ref buffer documentation for information on sending multiple
* buffers in one go, and how to use it with arrays, boost::array or
* std::vector.
*/
template <typename Const_Buffers>
std::size_t send(const Const_Buffers& buffers)
{
return this->service.send(this->implementation, buffers, 0, throw_error());
}
/// Send some data on the socket.
/**
* This function is used to send data on the stream socket. The function
* call will block until one or more bytes of the data has been sent
* successfully, or an until error occurs.
*
* @param buffers One or more data buffers to be sent on the socket.
*
* @param flags Flags specifying how the send call is to be made.
*
* @returns The number of bytes sent.
*
* @throws asio::error Thrown on failure.
*
* @note The send operation may not transmit all of the data to the peer.
* Consider using the @ref write function if you need to ensure that all data
* is written before the blocking operation completes.
*
* @par Example:
* To send a single data buffer use the @ref buffer function as follows:
* @code
* socket.send(asio::buffer(data, size), 0);
* @endcode
* See the @ref buffer documentation for information on sending multiple
* buffers in one go, and how to use it with arrays, boost::array or
* std::vector.
*/
template <typename Const_Buffers>
std::size_t send(const Const_Buffers& buffers,
socket_base::message_flags flags)
{
return this->service.send(this->implementation, buffers, flags,
throw_error());
}
/// Send some data on the socket.
/**
* This function is used to send data on the stream socket. The function
* call will block until one or more bytes of the data has been sent
* successfully, or an until error occurs.
*
* @param buffers One or more data buffers to be sent on the socket.
*
* @param flags Flags specifying how the send call is to be made.
*
* @param error_handler A handler to be called when the operation completes,
* to indicate whether or not an error has occurred. Copies will be made of
* the handler as required. The function signature of the handler must be:
* @code void error_handler(
* const asio::error& error // Result of operation.
* ); @endcode
*
* @returns The number of bytes sent. Returns 0 if an error occurred and the
* error handler did not throw an exception.
*
* @note The send operation may not transmit all of the data to the peer.
* Consider using the @ref write function if you need to ensure that all data
* is written before the blocking operation completes.
*/
template <typename Const_Buffers, typename Error_Handler>
std::size_t send(const Const_Buffers& buffers,
socket_base::message_flags flags,
Error_Handler error_handler)
{
return this->service.send(this->implementation, buffers, flags,
error_handler);
}
/// Start an asynchronous send.
/**
* This function is used to asynchronously send data on the stream socket.
* The function call always returns immediately.
*
* @param buffers One or more data buffers to be sent on the socket. 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 send 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& error, // Result of operation.
* std::size_t bytes_transferred // Number of bytes sent.
* ); @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_service::post().
*
* @note The send operation may not transmit all of the data to the peer.
* Consider using the @ref async_write function if you need to ensure that all
* data is written before the asynchronous operation completes.
*
* @par Example:
* To send a single data buffer use the @ref buffer function as follows:
* @code
* socket.async_send(asio::buffer(data, size), handler);
* @endcode
* See the @ref buffer documentation for information on sending multiple
* buffers in one go, and how to use it with arrays, boost::array or
* std::vector.
*/
template <typename Const_Buffers, typename Handler>
void async_send(const Const_Buffers& buffers, Handler handler)
{
this->service.async_send(this->implementation, buffers, 0, handler);
}
/// Start an asynchronous send.
/**
* This function is used to asynchronously send data on the stream socket.
* The function call always returns immediately.
*
* @param buffers One or more data buffers to be sent on the socket. 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 flags Flags specifying how the send call is to be made.
*
* @param handler The handler to be called when the send 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& error, // Result of operation.
* std::size_t bytes_transferred // Number of bytes sent.
* ); @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_service::post().
*
* @note The send operation may not transmit all of the data to the peer.
* Consider using the @ref async_write function if you need to ensure that all
* data is written before the asynchronous operation completes.
*
* @par Example:
* To send a single data buffer use the @ref buffer function as follows:
* @code
* socket.async_send(asio::buffer(data, size), 0, handler);
* @endcode
* See the @ref buffer documentation for information on sending multiple
* buffers in one go, and how to use it with arrays, boost::array or
* std::vector.
*/
template <typename Const_Buffers, typename Handler>
void async_send(const Const_Buffers& buffers,
socket_base::message_flags flags, Handler handler)
{
this->service.async_send(this->implementation, buffers, flags, handler);
}
/// Receive some data on the socket.
/**
* This function is used to receive data on the stream socket. The function
* call will block until one or more bytes of data has been received
* successfully, or until an error occurs.
*
* @param buffers One or more buffers into which the data will be received.
*
* @returns The number of bytes received.
*
* @throws asio::error Thrown on failure. An error code of
* asio::error::eof indicates that the connection was closed by the
* peer.
*
* @note The receive operation may not receive all of the requested number of
* bytes. Consider using the @ref read function if you need to ensure that the
* requested amount of data is read before the blocking operation completes.
*
* @par Example:
* To receive into a single data buffer use the @ref buffer function as
* follows:
* @code
* socket.receive(asio::buffer(data, size));
* @endcode
* See the @ref buffer documentation for information on receiving into
* multiple buffers in one go, and how to use it with arrays, boost::array or
* std::vector.
*/
template <typename Mutable_Buffers>
std::size_t receive(const Mutable_Buffers& buffers)
{
return this->service.receive(this->implementation, buffers, 0,
throw_error());
}
/// Receive some data on the socket.
/**
* This function is used to receive data on the stream socket. The function
* call will block until one or more bytes of data has been received
* successfully, or until an error occurs.
*
* @param buffers One or more buffers into which the data will be received.
*
* @param flags Flags specifying how the receive call is to be made.
*
* @returns The number of bytes received.
*
* @throws asio::error Thrown on failure. An error code of
* asio::error::eof indicates that the connection was closed by the
* peer.
*
* @note The receive operation may not receive all of the requested number of
* bytes. Consider using the @ref read function if you need to ensure that the
* requested amount of data is read before the blocking operation completes.
*
* @par Example:
* To receive into a single data buffer use the @ref buffer function as
* follows:
* @code
* socket.receive(asio::buffer(data, size), 0);
* @endcode
* See the @ref buffer documentation for information on receiving into
* multiple buffers in one go, and how to use it with arrays, boost::array or
* std::vector.
*/
template <typename Mutable_Buffers>
std::size_t receive(const Mutable_Buffers& buffers,
socket_base::message_flags flags)
{
return this->service.receive(this->implementation, buffers, flags,
throw_error());
}
/// Receive some data on a connected socket.
/**
* This function is used to receive data on the stream socket. The function
* call will block until one or more bytes of data has been received
* successfully, or until an error occurs.
*
* @param buffers One or more buffers into which the data will be received.
*
* @param flags Flags specifying how the receive call is to be made.
*
* @param error_handler A handler to be called when the operation completes,
* to indicate whether or not an error has occurred. Copies will be made of
* the handler as required. The function signature of the handler must be:
* @code void error_handler(
* const asio::error& error // Result of operation
* ); @endcode
*
* @returns The number of bytes received. Returns 0 if an error occurred and
* the error handler did not throw an exception.
*
* @note The receive operation may not receive all of the requested number of
* bytes. Consider using the @ref read function if you need to ensure that the
* requested amount of data is read before the blocking operation completes.
*/
template <typename Mutable_Buffers, typename Error_Handler>
std::size_t receive(const Mutable_Buffers& buffers,
socket_base::message_flags flags, Error_Handler error_handler)
{
return this->service.receive(this->implementation, buffers, flags,
error_handler);
}
/// Start an asynchronous receive.
/**
* This function is used to asynchronously receive data from the stream
* socket. The function call always returns immediately.
*
* @param buffers One or more buffers into which the data will be received.
* 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 receive 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& error, // Result of operation.
* std::size_t bytes_transferred // Number of bytes received.
* ); @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_service::post().
*
* @note The receive operation may not receive all of the requested number of
* bytes. Consider using the @ref async_read function if you need to ensure
* that the requested amount of data is received before the asynchronous
* operation completes.
*
* @par Example:
* To receive into a single data buffer use the @ref buffer function as
* follows:
* @code
* socket.async_receive(asio::buffer(data, size), handler);
* @endcode
* See the @ref buffer documentation for information on receiving into
* multiple buffers in one go, and how to use it with arrays, boost::array or
* std::vector.
*/
template <typename Mutable_Buffers, typename Handler>
void async_receive(const Mutable_Buffers& buffers, Handler handler)
{
this->service.async_receive(this->implementation, buffers, 0, handler);
}
/// Start an asynchronous receive.
/**
* This function is used to asynchronously receive data from the stream
* socket. The function call always returns immediately.
*
* @param buffers One or more buffers into which the data will be received.
* 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 flags Flags specifying how the receive call is to be made.
*
* @param handler The handler to be called when the receive 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& error, // Result of operation.
* std::size_t bytes_transferred // Number of bytes received.
* ); @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_service::post().
*
* @note The receive operation may not receive all of the requested number of
* bytes. Consider using the @ref async_read function if you need to ensure
* that the requested amount of data is received before the asynchronous
* operation completes.
*
* @par Example:
* To receive into a single data buffer use the @ref buffer function as
* follows:
* @code
* socket.async_receive(asio::buffer(data, size), 0, handler);
* @endcode
* See the @ref buffer documentation for information on receiving into
* multiple buffers in one go, and how to use it with arrays, boost::array or
* std::vector.
*/
template <typename Mutable_Buffers, typename Handler>
void async_receive(const Mutable_Buffers& buffers,
socket_base::message_flags flags, Handler handler)
{
this->service.async_receive(this->implementation, buffers, flags, handler);
}
/// Write some data to the socket.
/**
* This function is used to write data to the stream socket. The function call
* will block until one or more bytes of the data has been written
* successfully, or until an error occurs.
*
* @param buffers One or more data buffers to be written to the socket.
*
* @returns The number of bytes written.
*
* @throws asio::error Thrown on failure. An error code of
* asio::error::eof indicates that the connection was closed by the
* peer.
*
* @note The write_some operation may not transmit all of the data to the
* peer. Consider using the @ref write function if you need to ensure that
* all data is written before the blocking operation completes.
*
* @par Example:
* To write a single data buffer use the @ref buffer function as follows:
* @code
* socket.write_some(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.
*/
template <typename Const_Buffers>
std::size_t write_some(const Const_Buffers& buffers)
{
return this->service.send(this->implementation, buffers, 0, throw_error());
}
/// Write some data to the socket.
/**
* This function is used to write data to the stream socket. The function call
* will block until one or more bytes of the data has been written
* successfully, or until an error occurs.
*
* @param buffers One or more data buffers to be written to the socket.
*
* @param error_handler A handler to be called when the operation completes,
* to indicate whether or not an error has occurred. Copies will be made of
* the handler as required. The function signature of the handler must be:
* @code void error_handler(
* const asio::error& error // Result of operation.
* ); @endcode
*
* @returns The number of bytes written. Returns 0 if an error occurred and
* the error handler did not throw an exception.
*
* @note The write_some operation may not transmit all of the data to the
* peer. Consider using the @ref write function if you need to ensure that
* all data is written before the blocking operation completes.
*/
template <typename Const_Buffers, typename Error_Handler>
std::size_t write_some(const Const_Buffers& buffers,
Error_Handler error_handler)
{
return this->service.send(this->implementation, buffers, 0, error_handler);
}
/// Start an asynchronous write.
/**
* This function is used to asynchronously write data to the stream socket.
* The function call always returns immediately.
*
* @param buffers One or more data buffers to be written to the socket.
* 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(
* const asio::error& error, // Result of operation.
* std::size_t bytes_transferred // Number of bytes written.
* ); @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_service::post().
*
* @note The write operation may not transmit all of the data to the peer.
* Consider using the @ref async_write function if you need to ensure that all
* data is written before the asynchronous operation completes.
*
* @par Example:
* To write a single data buffer use the @ref buffer function as follows:
* @code
* socket.async_write_some(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 Const_Buffers, typename Handler>
void async_write_some(const Const_Buffers& buffers, Handler handler)
{
this->service.async_send(this->implementation, buffers, 0, handler);
}
/// Read some data from the socket.
/**
* This function is used to read data from the stream socket. The function
* call will block until one or more bytes of data has been read successfully,
* or until an error occurs.
*
* @param buffers One or more buffers into which the data will be read.
*
* @returns The number of bytes read.
*
* @throws asio::error Thrown on failure. An error code of
* asio::error::eof indicates that the connection was closed by the
* peer.
*
* @note The read_some operation may not read all of the requested number of
* bytes. Consider using the @ref read function if you need to ensure that
* the requested amount of data is read before the blocking operation
* completes.
*
* @par Example:
* To read into a single data buffer use the @ref buffer function as follows:
* @code
* socket.read_some(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.
*/
template <typename Mutable_Buffers>
std::size_t read_some(const Mutable_Buffers& buffers)
{
return this->service.receive(this->implementation, buffers, 0,
throw_error());
}
/// Read some data from the socket.
/**
* This function is used to read data from the stream socket. The function
* call will block until one or more bytes of data has been read successfully,
* or until an error occurs.
*
* @param buffers One or more buffers into which the data will be read.
*
* @param error_handler A handler to be called when the operation completes,
* to indicate whether or not an error has occurred. Copies will be made of
* the handler as required. The function signature of the handler must be:
* @code void error_handler(
* const asio::error& error // Result of operation.
* ); @endcode
*
* @returns The number of bytes read. Returns 0 if an error occurred and the
* error handler did not throw an exception.
*
* @note The read_some operation may not read all of the requested number of
* bytes. Consider using the @ref read function if you need to ensure that
* the requested amount of data is read before the blocking operation
* completes.
*/
template <typename Mutable_Buffers, typename Error_Handler>
std::size_t read_some(const Mutable_Buffers& buffers,
Error_Handler error_handler)
{
return this->service.receive(this->implementation, buffers, 0,
error_handler);
}
/// Start an asynchronous read.
/**
* This function is used to asynchronously read data from the stream socket.
* The function call always returns immediately.
*
* @param buffers One or more buffers 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& error, // Result of operation.
* std::size_t bytes_transferred // Number of bytes read.
* ); @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_service::post().
*
* @note The read operation may not read all of the requested number of bytes.
* Consider using the @ref async_read function if you need to ensure that the
* requested amount of data is read before the asynchronous operation
* completes.
*
* @par Example:
* To read into a single data buffer use the @ref buffer function as follows:
* @code
* socket.async_read_some(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.
*/
template <typename Mutable_Buffers, typename Handler>
void async_read_some(const Mutable_Buffers& buffers, Handler handler)
{
this->service.async_receive(this->implementation, buffers, 0, handler);
}
/// Peek at the incoming data on the stream socket.
/**
* This function is used to peek at the incoming data on the stream socket,
* without removing it from the input queue. The function call will block
* until data has been read successfully or an error occurs.
*
* @param buffers One or more buffers into which the data will be read.
*
* @returns The number of bytes read.
*
* @throws asio::error Thrown on failure.
*
* @par Example:
* To peek using a single data buffer use the @ref buffer function as
* follows:
* @code socket.peek(asio::buffer(data, size)); @endcode
* See the @ref buffer documentation for information on using multiple
* buffers in one go, and how to use it with arrays, boost::array or
* std::vector.
*/
template <typename Mutable_Buffers>
std::size_t peek(const Mutable_Buffers& buffers)
{
return this->service.receive(this->implementation, buffers,
socket_base::message_peek, throw_error());
}
/// Peek at the incoming data on the stream socket.
/**
* This function is used to peek at the incoming data on the stream socket,
* without removing it from the input queue. The function call will block
* until data has been read successfully or an error occurs.
*
* @param buffers One or more buffers into which the data will be read.
*
* @param error_handler A handler to be called when the operation completes,
* to indicate whether or not an error has occurred. Copies will be made of
* the handler as required. The function signature of the handler must be:
* @code void error_handler(
* const asio::error& error // Result of operation.
* ); @endcode
*
* @returns The number of bytes read. Returns 0 if an error occurred and the
* error handler did not throw an exception.
*/
template <typename Mutable_Buffers, typename Error_Handler>
std::size_t peek(const Mutable_Buffers& buffers, Error_Handler error_handler)
{
return this->service.receive(this->implementation, buffers,
socket_base::message_peek, error_handler);
}
/// Determine the amount of data that may be read without blocking.
/**
* This function is used to determine the amount of data, in bytes, that may
* be read from the stream socket without blocking.
*
* @returns The number of bytes of data that can be read without blocking.
*
* @throws asio::error Thrown on failure.
*/
std::size_t in_avail()
{
socket_base::bytes_readable command;
this->service.io_control(this->implementation, command, throw_error());
return command.get();
}
/// Determine the amount of data that may be read without blocking.
/**
* This function is used to determine the amount of data, in bytes, that may
* be read from the stream socket without blocking.
*
* @param error_handler A handler to be called when the operation completes,
* to indicate whether or not an error has occurred. Copies will be made of
* the handler as required. The function signature of the handler must be:
* @code void error_handler(
* const asio::error& error // Result of operation
* ); @endcode
*
* @returns The number of bytes of data that can be read without blocking.
*/
template <typename Error_Handler>
std::size_t in_avail(Error_Handler error_handler)
{
socket_base::bytes_readable command;
this->service.io_control(this->implementation, command, error_handler);
return command.get();
}
};
} // namespace asio
#include "asio/detail/pop_options.hpp"
#endif // ASIO_BASIC_STREAM_SOCKET_HPP