deluge/libtorrent/include/asio/posix/basic_descriptor.hpp

295 lines
8.7 KiB
C++

//
// basic_descriptor.hpp
// ~~~~~~~~~~~~~~~~~~~~
//
// Copyright (c) 2003-2008 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_POSIX_BASIC_DESCRIPTOR_HPP
#define ASIO_POSIX_BASIC_DESCRIPTOR_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 <boost/config.hpp>
#include "asio/detail/pop_options.hpp"
#include "asio/basic_io_object.hpp"
#include "asio/error.hpp"
#include "asio/posix/descriptor_base.hpp"
#include "asio/detail/throw_error.hpp"
namespace asio {
namespace posix {
/// Provides POSIX descriptor functionality.
/**
* The posix::basic_descriptor class template provides the ability to wrap a
* POSIX descriptor.
*
* @par Thread Safety
* @e Distinct @e objects: Safe.@n
* @e Shared @e objects: Unsafe.
*/
template <typename DescriptorService>
class basic_descriptor
: public basic_io_object<DescriptorService>,
public descriptor_base
{
public:
/// The native representation of a descriptor.
typedef typename DescriptorService::native_type native_type;
/// A basic_descriptor is always the lowest layer.
typedef basic_descriptor<DescriptorService> lowest_layer_type;
/// Construct a basic_descriptor without opening it.
/**
* This constructor creates a descriptor without opening it.
*
* @param io_service The io_service object that the descriptor will use to
* dispatch handlers for any asynchronous operations performed on the
* descriptor.
*/
explicit basic_descriptor(asio::io_service& io_service)
: basic_io_object<DescriptorService>(io_service)
{
}
/// Construct a basic_descriptor on an existing native descriptor.
/**
* This constructor creates a descriptor object to hold an existing native
* descriptor.
*
* @param io_service The io_service object that the descriptor will use to
* dispatch handlers for any asynchronous operations performed on the
* descriptor.
*
* @param native_descriptor A native descriptor.
*
* @throws asio::system_error Thrown on failure.
*/
basic_descriptor(asio::io_service& io_service,
const native_type& native_descriptor)
: basic_io_object<DescriptorService>(io_service)
{
asio::error_code ec;
this->service.assign(this->implementation, native_descriptor, ec);
asio::detail::throw_error(ec);
}
/// Get a reference to the lowest layer.
/**
* This function returns a reference to the lowest layer in a stack of
* layers. Since a basic_descriptor cannot contain any further layers, it
* simply returns a reference to itself.
*
* @return A reference to the lowest layer in the stack of layers. Ownership
* is not transferred to the caller.
*/
lowest_layer_type& lowest_layer()
{
return *this;
}
/// Get a const reference to the lowest layer.
/**
* This function returns a const reference to the lowest layer in a stack of
* layers. Since a basic_descriptor cannot contain any further layers, it
* simply returns a reference to itself.
*
* @return A const reference to the lowest layer in the stack of layers.
* Ownership is not transferred to the caller.
*/
const lowest_layer_type& lowest_layer() const
{
return *this;
}
/// Assign an existing native descriptor to the descriptor.
/*
* This function opens the descriptor to hold an existing native descriptor.
*
* @param native_descriptor A native descriptor.
*
* @throws asio::system_error Thrown on failure.
*/
void assign(const native_type& native_descriptor)
{
asio::error_code ec;
this->service.assign(this->implementation, native_descriptor, ec);
asio::detail::throw_error(ec);
}
/// Assign an existing native descriptor to the descriptor.
/*
* This function opens the descriptor to hold an existing native descriptor.
*
* @param native_descriptor A native descriptor.
*
* @param ec Set to indicate what error occurred, if any.
*/
asio::error_code assign(const native_type& native_descriptor,
asio::error_code& ec)
{
return this->service.assign(this->implementation, native_descriptor, ec);
}
/// Determine whether the descriptor is open.
bool is_open() const
{
return this->service.is_open(this->implementation);
}
/// Close the descriptor.
/**
* This function is used to close the descriptor. Any asynchronous read or
* write operations will be cancelled immediately, and will complete with the
* asio::error::operation_aborted error.
*
* @throws asio::system_error Thrown on failure.
*/
void close()
{
asio::error_code ec;
this->service.close(this->implementation, ec);
asio::detail::throw_error(ec);
}
/// Close the descriptor.
/**
* This function is used to close the descriptor. Any asynchronous read or
* write operations will be cancelled immediately, and will complete with the
* asio::error::operation_aborted error.
*
* @param ec Set to indicate what error occurred, if any.
*/
asio::error_code close(asio::error_code& ec)
{
return this->service.close(this->implementation, ec);
}
/// Get the native descriptor representation.
/**
* This function may be used to obtain the underlying representation of the
* descriptor. This is intended to allow access to native descriptor
* functionality that is not otherwise provided.
*/
native_type native()
{
return this->service.native(this->implementation);
}
/// Cancel all asynchronous operations associated with the descriptor.
/**
* This function causes all outstanding asynchronous read or write operations
* to finish immediately, and the handlers for cancelled operations will be
* passed the asio::error::operation_aborted error.
*
* @throws asio::system_error Thrown on failure.
*/
void cancel()
{
asio::error_code ec;
this->service.cancel(this->implementation, ec);
asio::detail::throw_error(ec);
}
/// Cancel all asynchronous operations associated with the descriptor.
/**
* This function causes all outstanding asynchronous read or write operations
* to finish immediately, and the handlers for cancelled operations will be
* passed the asio::error::operation_aborted error.
*
* @param ec Set to indicate what error occurred, if any.
*/
asio::error_code cancel(asio::error_code& ec)
{
return this->service.cancel(this->implementation, ec);
}
/// Perform an IO control command on the descriptor.
/**
* This function is used to execute an IO control command on the descriptor.
*
* @param command The IO control command to be performed on the descriptor.
*
* @throws asio::system_error Thrown on failure.
*
* @sa IoControlCommand @n
* asio::posix::descriptor_base::bytes_readable @n
* asio::posix::descriptor_base::non_blocking_io
*
* @par Example
* Getting the number of bytes ready to read:
* @code
* asio::posix::stream_descriptor descriptor(io_service);
* ...
* asio::posix::stream_descriptor::bytes_readable command;
* descriptor.io_control(command);
* std::size_t bytes_readable = command.get();
* @endcode
*/
template <typename IoControlCommand>
void io_control(IoControlCommand& command)
{
asio::error_code ec;
this->service.io_control(this->implementation, command, ec);
asio::detail::throw_error(ec);
}
/// Perform an IO control command on the descriptor.
/**
* This function is used to execute an IO control command on the descriptor.
*
* @param command The IO control command to be performed on the descriptor.
*
* @param ec Set to indicate what error occurred, if any.
*
* @sa IoControlCommand @n
* asio::posix::descriptor_base::bytes_readable @n
* asio::posix::descriptor_base::non_blocking_io
*
* @par Example
* Getting the number of bytes ready to read:
* @code
* asio::posix::stream_descriptor descriptor(io_service);
* ...
* asio::posix::stream_descriptor::bytes_readable command;
* asio::error_code ec;
* descriptor.io_control(command, ec);
* if (ec)
* {
* // An error occurred.
* }
* std::size_t bytes_readable = command.get();
* @endcode
*/
template <typename IoControlCommand>
asio::error_code io_control(IoControlCommand& command,
asio::error_code& ec)
{
return this->service.io_control(this->implementation, command, ec);
}
protected:
/// Protected destructor to prevent deletion through this type.
~basic_descriptor()
{
}
};
} // namespace posix
} // namespace asio
#include "asio/detail/pop_options.hpp"
#endif // ASIO_POSIX_BASIC_DESCRIPTOR_HPP