boost/asio/ip/basic_resolver.hpp
//
// ip/basic_resolver.hpp
// ~~~~~~~~~~~~~~~~~~~~~
//
// Copyright (c) 2003-2023 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_IP_BASIC_RESOLVER_HPP
#define BOOST_ASIO_IP_BASIC_RESOLVER_HPP
#if defined(_MSC_VER) && (_MSC_VER >= 1200)
# pragma once
#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
#include <boost/asio/detail/config.hpp>
#include <string>
#include <utility>
#include <boost/asio/any_io_executor.hpp>
#include <boost/asio/async_result.hpp>
#include <boost/asio/detail/handler_type_requirements.hpp>
#include <boost/asio/detail/io_object_impl.hpp>
#include <boost/asio/detail/non_const_lvalue.hpp>
#include <boost/asio/detail/string_view.hpp>
#include <boost/asio/detail/throw_error.hpp>
#include <boost/asio/error.hpp>
#include <boost/asio/execution_context.hpp>
#include <boost/asio/ip/basic_resolver_iterator.hpp>
#include <boost/asio/ip/basic_resolver_query.hpp>
#include <boost/asio/ip/basic_resolver_results.hpp>
#include <boost/asio/ip/resolver_base.hpp>
#if defined(BOOST_ASIO_WINDOWS_RUNTIME)
# include <boost/asio/detail/winrt_resolver_service.hpp>
#else
# include <boost/asio/detail/resolver_service.hpp>
#endif
#include <boost/asio/detail/push_options.hpp>
namespace boost {
namespace asio {
namespace ip {
#if !defined(BOOST_ASIO_IP_BASIC_RESOLVER_FWD_DECL)
#define BOOST_ASIO_IP_BASIC_RESOLVER_FWD_DECL
// Forward declaration with defaulted arguments.
template <typename InternetProtocol, typename Executor = any_io_executor>
class basic_resolver;
#endif // !defined(BOOST_ASIO_IP_BASIC_RESOLVER_FWD_DECL)
/// Provides endpoint resolution functionality.
/**
* The basic_resolver class template provides the ability to resolve a query
* to a list of endpoints.
*
* @par Thread Safety
* @e Distinct @e objects: Safe.@n
* @e Shared @e objects: Unsafe.
*/
template <typename InternetProtocol, typename Executor>
class basic_resolver
: public resolver_base
{
private:
class initiate_async_resolve;
public:
/// The type of the executor associated with the object.
typedef Executor executor_type;
/// Rebinds the resolver type to another executor.
template <typename Executor1>
struct rebind_executor
{
/// The resolver type when rebound to the specified executor.
typedef basic_resolver<InternetProtocol, Executor1> other;
};
/// The protocol type.
typedef InternetProtocol protocol_type;
/// The endpoint type.
typedef typename InternetProtocol::endpoint endpoint_type;
#if !defined(BOOST_ASIO_NO_DEPRECATED)
/// (Deprecated.) The query type.
typedef basic_resolver_query<InternetProtocol> query;
/// (Deprecated.) The iterator type.
typedef basic_resolver_iterator<InternetProtocol> iterator;
#endif // !defined(BOOST_ASIO_NO_DEPRECATED)
/// The results type.
typedef basic_resolver_results<InternetProtocol> results_type;
/// Construct with executor.
/**
* This constructor creates a basic_resolver.
*
* @param ex The I/O executor that the resolver will use, by default, to
* dispatch handlers for any asynchronous operations performed on the
* resolver.
*/
explicit basic_resolver(const executor_type& ex)
: impl_(0, ex)
{
}
/// Construct with execution context.
/**
* This constructor creates a basic_resolver.
*
* @param context An execution context which provides the I/O executor that
* the resolver will use, by default, to dispatch handlers for any
* asynchronous operations performed on the resolver.
*/
template <typename ExecutionContext>
explicit basic_resolver(ExecutionContext& context,
constraint_t<
is_convertible<ExecutionContext&, execution_context&>::value
> = 0)
: impl_(0, 0, context)
{
}
/// Move-construct a basic_resolver from another.
/**
* This constructor moves a resolver from one object to another.
*
* @param other The other basic_resolver object from which the move will
* occur.
*
* @note Following the move, the moved-from object is in the same state as if
* constructed using the @c basic_resolver(const executor_type&) constructor.
*/
basic_resolver(basic_resolver&& other)
: impl_(std::move(other.impl_))
{
}
// All resolvers have access to each other's implementations.
template <typename InternetProtocol1, typename Executor1>
friend class basic_resolver;
/// Move-construct a basic_resolver from another.
/**
* This constructor moves a resolver from one object to another.
*
* @param other The other basic_resolver object from which the move will
* occur.
*
* @note Following the move, the moved-from object is in the same state as if
* constructed using the @c basic_resolver(const executor_type&) constructor.
*/
template <typename Executor1>
basic_resolver(basic_resolver<InternetProtocol, Executor1>&& other,
constraint_t<
is_convertible<Executor1, Executor>::value
> = 0)
: impl_(std::move(other.impl_))
{
}
/// Move-assign a basic_resolver from another.
/**
* This assignment operator moves a resolver from one object to another.
* Cancels any outstanding asynchronous operations associated with the target
* object.
*
* @param other The other basic_resolver object from which the move will
* occur.
*
* @note Following the move, the moved-from object is in the same state as if
* constructed using the @c basic_resolver(const executor_type&) constructor.
*/
basic_resolver& operator=(basic_resolver&& other)
{
impl_ = std::move(other.impl_);
return *this;
}
/// Move-assign a basic_resolver from another.
/**
* This assignment operator moves a resolver from one object to another.
* Cancels any outstanding asynchronous operations associated with the target
* object.
*
* @param other The other basic_resolver object from which the move will
* occur.
*
* @note Following the move, the moved-from object is in the same state as if
* constructed using the @c basic_resolver(const executor_type&) constructor.
*/
template <typename Executor1>
constraint_t<
is_convertible<Executor1, Executor>::value,
basic_resolver&
> operator=(basic_resolver<InternetProtocol, Executor1>&& other)
{
basic_resolver tmp(std::move(other));
impl_ = std::move(tmp.impl_);
return *this;
}
/// Destroys the resolver.
/**
* This function destroys the resolver, cancelling any outstanding
* asynchronous wait operations associated with the resolver as if by calling
* @c cancel.
*/
~basic_resolver()
{
}
/// Get the executor associated with the object.
executor_type get_executor() noexcept
{
return impl_.get_executor();
}
/// Cancel any asynchronous operations that are waiting on the resolver.
/**
* This function forces the completion of any pending asynchronous
* operations on the host resolver. The handler for each cancelled operation
* will be invoked with the boost::asio::error::operation_aborted error code.
*/
void cancel()
{
return impl_.get_service().cancel(impl_.get_implementation());
}
#if !defined(BOOST_ASIO_NO_DEPRECATED)
/// (Deprecated: Use overload with separate host and service parameters.)
/// Perform forward resolution of a query to a list of entries.
/**
* This function is used to resolve a query into a list of endpoint entries.
*
* @param q A query object that determines what endpoints will be returned.
*
* @returns A range object representing the list of endpoint entries. A
* successful call to this function is guaranteed to return a non-empty
* range.
*
* @throws boost::system::system_error Thrown on failure.
*/
results_type resolve(const query& q)
{
boost::system::error_code ec;
results_type r = impl_.get_service().resolve(
impl_.get_implementation(), q, ec);
boost::asio::detail::throw_error(ec, "resolve");
return r;
}
/// (Deprecated: Use overload with separate host and service parameters.)
/// Perform forward resolution of a query to a list of entries.
/**
* This function is used to resolve a query into a list of endpoint entries.
*
* @param q A query object that determines what endpoints will be returned.
*
* @param ec Set to indicate what error occurred, if any.
*
* @returns A range object representing the list of endpoint entries. An
* empty range is returned if an error occurs. A successful call to this
* function is guaranteed to return a non-empty range.
*/
results_type resolve(const query& q, boost::system::error_code& ec)
{
return impl_.get_service().resolve(impl_.get_implementation(), q, ec);
}
#endif // !defined(BOOST_ASIO_NO_DEPRECATED)
/// Perform forward resolution of a query to a list of entries.
/**
* This function is used to resolve host and service names into a list of
* endpoint entries.
*
* @param host A string identifying a location. May be a descriptive name or
* a numeric address string. If an empty string and the passive flag has been
* specified, the resolved endpoints are suitable for local service binding.
* If an empty string and passive is not specified, the resolved endpoints
* will use the loopback address.
*
* @param service A string identifying the requested service. This may be a
* descriptive name or a numeric string corresponding to a port number. May
* be an empty string, in which case all resolved endpoints will have a port
* number of 0.
*
* @returns A range object representing the list of endpoint entries. A
* successful call to this function is guaranteed to return a non-empty
* range.
*
* @throws boost::system::system_error Thrown on failure.
*
* @note On POSIX systems, host names may be locally defined in the file
* <tt>/etc/hosts</tt>. On Windows, host names may be defined in the file
* <tt>c:\\windows\\system32\\drivers\\etc\\hosts</tt>. Remote host name
* resolution is performed using DNS. Operating systems may use additional
* locations when resolving host names (such as NETBIOS names on Windows).
*
* On POSIX systems, service names are typically defined in the file
* <tt>/etc/services</tt>. On Windows, service names may be found in the file
* <tt>c:\\windows\\system32\\drivers\\etc\\services</tt>. Operating systems
* may use additional locations when resolving service names.
*/
results_type resolve(BOOST_ASIO_STRING_VIEW_PARAM host,
BOOST_ASIO_STRING_VIEW_PARAM service)
{
return resolve(host, service, resolver_base::flags());
}
/// Perform forward resolution of a query to a list of entries.
/**
* This function is used to resolve host and service names into a list of
* endpoint entries.
*
* @param host A string identifying a location. May be a descriptive name or
* a numeric address string. If an empty string and the passive flag has been
* specified, the resolved endpoints are suitable for local service binding.
* If an empty string and passive is not specified, the resolved endpoints
* will use the loopback address.
*
* @param service A string identifying the requested service. This may be a
* descriptive name or a numeric string corresponding to a port number. May
* be an empty string, in which case all resolved endpoints will have a port
* number of 0.
*
* @param ec Set to indicate what error occurred, if any.
*
* @returns A range object representing the list of endpoint entries. An
* empty range is returned if an error occurs. A successful call to this
* function is guaranteed to return a non-empty range.
*
* @note On POSIX systems, host names may be locally defined in the file
* <tt>/etc/hosts</tt>. On Windows, host names may be defined in the file
* <tt>c:\\windows\\system32\\drivers\\etc\\hosts</tt>. Remote host name
* resolution is performed using DNS. Operating systems may use additional
* locations when resolving host names (such as NETBIOS names on Windows).
*
* On POSIX systems, service names are typically defined in the file
* <tt>/etc/services</tt>. On Windows, service names may be found in the file
* <tt>c:\\windows\\system32\\drivers\\etc\\services</tt>. Operating systems
* may use additional locations when resolving service names.
*/
results_type resolve(BOOST_ASIO_STRING_VIEW_PARAM host,
BOOST_ASIO_STRING_VIEW_PARAM service, boost::system::error_code& ec)
{
return resolve(host, service, resolver_base::flags(), ec);
}
/// Perform forward resolution of a query to a list of entries.
/**
* This function is used to resolve host and service names into a list of
* endpoint entries.
*
* @param host A string identifying a location. May be a descriptive name or
* a numeric address string. If an empty string and the passive flag has been
* specified, the resolved endpoints are suitable for local service binding.
* If an empty string and passive is not specified, the resolved endpoints
* will use the loopback address.
*
* @param service A string identifying the requested service. This may be a
* descriptive name or a numeric string corresponding to a port number. May
* be an empty string, in which case all resolved endpoints will have a port
* number of 0.
*
* @param resolve_flags A set of flags that determine how name resolution
* should be performed. The default flags are suitable for communication with
* remote hosts. See the @ref resolver_base documentation for the set of
* available flags.
*
* @returns A range object representing the list of endpoint entries. A
* successful call to this function is guaranteed to return a non-empty
* range.
*
* @throws boost::system::system_error Thrown on failure.
*
* @note On POSIX systems, host names may be locally defined in the file
* <tt>/etc/hosts</tt>. On Windows, host names may be defined in the file
* <tt>c:\\windows\\system32\\drivers\\etc\\hosts</tt>. Remote host name
* resolution is performed using DNS. Operating systems may use additional
* locations when resolving host names (such as NETBIOS names on Windows).
*
* On POSIX systems, service names are typically defined in the file
* <tt>/etc/services</tt>. On Windows, service names may be found in the file
* <tt>c:\\windows\\system32\\drivers\\etc\\services</tt>. Operating systems
* may use additional locations when resolving service names.
*/
results_type resolve(BOOST_ASIO_STRING_VIEW_PARAM host,
BOOST_ASIO_STRING_VIEW_PARAM service, resolver_base::flags resolve_flags)
{
boost::system::error_code ec;
basic_resolver_query<protocol_type> q(static_cast<std::string>(host),
static_cast<std::string>(service), resolve_flags);
results_type r = impl_.get_service().resolve(
impl_.get_implementation(), q, ec);
boost::asio::detail::throw_error(ec, "resolve");
return r;
}
/// Perform forward resolution of a query to a list of entries.
/**
* This function is used to resolve host and service names into a list of
* endpoint entries.
*
* @param host A string identifying a location. May be a descriptive name or
* a numeric address string. If an empty string and the passive flag has been
* specified, the resolved endpoints are suitable for local service binding.
* If an empty string and passive is not specified, the resolved endpoints
* will use the loopback address.
*
* @param service A string identifying the requested service. This may be a
* descriptive name or a numeric string corresponding to a port number. May
* be an empty string, in which case all resolved endpoints will have a port
* number of 0.
*
* @param resolve_flags A set of flags that determine how name resolution
* should be performed. The default flags are suitable for communication with
* remote hosts. See the @ref resolver_base documentation for the set of
* available flags.
*
* @param ec Set to indicate what error occurred, if any.
*
* @returns A range object representing the list of endpoint entries. An
* empty range is returned if an error occurs. A successful call to this
* function is guaranteed to return a non-empty range.
*
* @note On POSIX systems, host names may be locally defined in the file
* <tt>/etc/hosts</tt>. On Windows, host names may be defined in the file
* <tt>c:\\windows\\system32\\drivers\\etc\\hosts</tt>. Remote host name
* resolution is performed using DNS. Operating systems may use additional
* locations when resolving host names (such as NETBIOS names on Windows).
*
* On POSIX systems, service names are typically defined in the file
* <tt>/etc/services</tt>. On Windows, service names may be found in the file
* <tt>c:\\windows\\system32\\drivers\\etc\\services</tt>. Operating systems
* may use additional locations when resolving service names.
*/
results_type resolve(BOOST_ASIO_STRING_VIEW_PARAM host,
BOOST_ASIO_STRING_VIEW_PARAM service, resolver_base::flags resolve_flags,
boost::system::error_code& ec)
{
basic_resolver_query<protocol_type> q(static_cast<std::string>(host),
static_cast<std::string>(service), resolve_flags);
return impl_.get_service().resolve(impl_.get_implementation(), q, ec);
}
/// Perform forward resolution of a query to a list of entries.
/**
* This function is used to resolve host and service names into a list of
* endpoint entries.
*
* @param protocol A protocol object, normally representing either the IPv4 or
* IPv6 version of an internet protocol.
*
* @param host A string identifying a location. May be a descriptive name or
* a numeric address string. If an empty string and the passive flag has been
* specified, the resolved endpoints are suitable for local service binding.
* If an empty string and passive is not specified, the resolved endpoints
* will use the loopback address.
*
* @param service A string identifying the requested service. This may be a
* descriptive name or a numeric string corresponding to a port number. May
* be an empty string, in which case all resolved endpoints will have a port
* number of 0.
*
* @returns A range object representing the list of endpoint entries. A
* successful call to this function is guaranteed to return a non-empty
* range.
*
* @throws boost::system::system_error Thrown on failure.
*
* @note On POSIX systems, host names may be locally defined in the file
* <tt>/etc/hosts</tt>. On Windows, host names may be defined in the file
* <tt>c:\\windows\\system32\\drivers\\etc\\hosts</tt>. Remote host name
* resolution is performed using DNS. Operating systems may use additional
* locations when resolving host names (such as NETBIOS names on Windows).
*
* On POSIX systems, service names are typically defined in the file
* <tt>/etc/services</tt>. On Windows, service names may be found in the file
* <tt>c:\\windows\\system32\\drivers\\etc\\services</tt>. Operating systems
* may use additional locations when resolving service names.
*/
results_type resolve(const protocol_type& protocol,
BOOST_ASIO_STRING_VIEW_PARAM host, BOOST_ASIO_STRING_VIEW_PARAM service)
{
return resolve(protocol, host, service, resolver_base::flags());
}
/// Perform forward resolution of a query to a list of entries.
/**
* This function is used to resolve host and service names into a list of
* endpoint entries.
*
* @param protocol A protocol object, normally representing either the IPv4 or
* IPv6 version of an internet protocol.
*
* @param host A string identifying a location. May be a descriptive name or
* a numeric address string. If an empty string and the passive flag has been
* specified, the resolved endpoints are suitable for local service binding.
* If an empty string and passive is not specified, the resolved endpoints
* will use the loopback address.
*
* @param service A string identifying the requested service. This may be a
* descriptive name or a numeric string corresponding to a port number. May
* be an empty string, in which case all resolved endpoints will have a port
* number of 0.
*
* @param ec Set to indicate what error occurred, if any.
*
* @returns A range object representing the list of endpoint entries. An
* empty range is returned if an error occurs. A successful call to this
* function is guaranteed to return a non-empty range.
*
* @note On POSIX systems, host names may be locally defined in the file
* <tt>/etc/hosts</tt>. On Windows, host names may be defined in the file
* <tt>c:\\windows\\system32\\drivers\\etc\\hosts</tt>. Remote host name
* resolution is performed using DNS. Operating systems may use additional
* locations when resolving host names (such as NETBIOS names on Windows).
*
* On POSIX systems, service names are typically defined in the file
* <tt>/etc/services</tt>. On Windows, service names may be found in the file
* <tt>c:\\windows\\system32\\drivers\\etc\\services</tt>. Operating systems
* may use additional locations when resolving service names.
*/
results_type resolve(const protocol_type& protocol,
BOOST_ASIO_STRING_VIEW_PARAM host, BOOST_ASIO_STRING_VIEW_PARAM service,
boost::system::error_code& ec)
{
return resolve(protocol, host, service, resolver_base::flags(), ec);
}
/// Perform forward resolution of a query to a list of entries.
/**
* This function is used to resolve host and service names into a list of
* endpoint entries.
*
* @param protocol A protocol object, normally representing either the IPv4 or
* IPv6 version of an internet protocol.
*
* @param host A string identifying a location. May be a descriptive name or
* a numeric address string. If an empty string and the passive flag has been
* specified, the resolved endpoints are suitable for local service binding.
* If an empty string and passive is not specified, the resolved endpoints
* will use the loopback address.
*
* @param service A string identifying the requested service. This may be a
* descriptive name or a numeric string corresponding to a port number. May
* be an empty string, in which case all resolved endpoints will have a port
* number of 0.
*
* @param resolve_flags A set of flags that determine how name resolution
* should be performed. The default flags are suitable for communication with
* remote hosts. See the @ref resolver_base documentation for the set of
* available flags.
*
* @returns A range object representing the list of endpoint entries. A
* successful call to this function is guaranteed to return a non-empty
* range.
*
* @throws boost::system::system_error Thrown on failure.
*
* @note On POSIX systems, host names may be locally defined in the file
* <tt>/etc/hosts</tt>. On Windows, host names may be defined in the file
* <tt>c:\\windows\\system32\\drivers\\etc\\hosts</tt>. Remote host name
* resolution is performed using DNS. Operating systems may use additional
* locations when resolving host names (such as NETBIOS names on Windows).
*
* On POSIX systems, service names are typically defined in the file
* <tt>/etc/services</tt>. On Windows, service names may be found in the file
* <tt>c:\\windows\\system32\\drivers\\etc\\services</tt>. Operating systems
* may use additional locations when resolving service names.
*/
results_type resolve(const protocol_type& protocol,
BOOST_ASIO_STRING_VIEW_PARAM host, BOOST_ASIO_STRING_VIEW_PARAM service,
resolver_base::flags resolve_flags)
{
boost::system::error_code ec;
basic_resolver_query<protocol_type> q(
protocol, static_cast<std::string>(host),
static_cast<std::string>(service), resolve_flags);
results_type r = impl_.get_service().resolve(
impl_.get_implementation(), q, ec);
boost::asio::detail::throw_error(ec, "resolve");
return r;
}
/// Perform forward resolution of a query to a list of entries.
/**
* This function is used to resolve host and service names into a list of
* endpoint entries.
*
* @param protocol A protocol object, normally representing either the IPv4 or
* IPv6 version of an internet protocol.
*
* @param host A string identifying a location. May be a descriptive name or
* a numeric address string. If an empty string and the passive flag has been
* specified, the resolved endpoints are suitable for local service binding.
* If an empty string and passive is not specified, the resolved endpoints
* will use the loopback address.
*
* @param service A string identifying the requested service. This may be a
* descriptive name or a numeric string corresponding to a port number. May
* be an empty string, in which case all resolved endpoints will have a port
* number of 0.
*
* @param resolve_flags A set of flags that determine how name resolution
* should be performed. The default flags are suitable for communication with
* remote hosts. See the @ref resolver_base documentation for the set of
* available flags.
*
* @param ec Set to indicate what error occurred, if any.
*
* @returns A range object representing the list of endpoint entries. An
* empty range is returned if an error occurs. A successful call to this
* function is guaranteed to return a non-empty range.
*
* @note On POSIX systems, host names may be locally defined in the file
* <tt>/etc/hosts</tt>. On Windows, host names may be defined in the file
* <tt>c:\\windows\\system32\\drivers\\etc\\hosts</tt>. Remote host name
* resolution is performed using DNS. Operating systems may use additional
* locations when resolving host names (such as NETBIOS names on Windows).
*
* On POSIX systems, service names are typically defined in the file
* <tt>/etc/services</tt>. On Windows, service names may be found in the file
* <tt>c:\\windows\\system32\\drivers\\etc\\services</tt>. Operating systems
* may use additional locations when resolving service names.
*/
results_type resolve(const protocol_type& protocol,
BOOST_ASIO_STRING_VIEW_PARAM host, BOOST_ASIO_STRING_VIEW_PARAM service,
resolver_base::flags resolve_flags, boost::system::error_code& ec)
{
basic_resolver_query<protocol_type> q(
protocol, static_cast<std::string>(host),
static_cast<std::string>(service), resolve_flags);
return impl_.get_service().resolve(impl_.get_implementation(), q, ec);
}
#if !defined(BOOST_ASIO_NO_DEPRECATED)
/// (Deprecated: Use overload with separate host and service parameters.)
/// Asynchronously perform forward resolution of a query to a list of entries.
/**
* This function is used to asynchronously resolve a query into a list of
* endpoint entries. It is an initiating function for an @ref
* asynchronous_operation, and always returns immediately.
*
* @param q A query object that determines what endpoints will be returned.
*
* @param token The @ref completion_token that will be used to produce a
* completion handler, which will be called when the resolve completes.
* Potential completion tokens include @ref use_future, @ref use_awaitable,
* @ref yield_context, or a function object with the correct completion
* signature. The function signature of the completion handler must be:
* @code void handler(
* const boost::system::error_code& error, // Result of operation.
* resolver::results_type results // Resolved endpoints as a range.
* ); @endcode
* Regardless of whether the asynchronous operation completes immediately or
* not, the completion handler will not be invoked from within this function.
* On immediate completion, invocation of the handler will be performed in a
* manner equivalent to using boost::asio::post().
*
* A successful resolve operation is guaranteed to pass a non-empty range to
* the handler.
*
* @par Completion Signature
* @code void(boost::system::error_code, results_type) @endcode
*/
template <
BOOST_ASIO_COMPLETION_TOKEN_FOR(void (boost::system::error_code,
results_type)) ResolveToken = default_completion_token_t<executor_type>>
auto async_resolve(const query& q,
ResolveToken&& token = default_completion_token_t<executor_type>())
-> decltype(
boost::asio::async_initiate<ResolveToken,
void (boost::system::error_code, results_type)>(
declval<initiate_async_resolve>(), token, q))
{
return boost::asio::async_initiate<ResolveToken,
void (boost::system::error_code, results_type)>(
initiate_async_resolve(this), token, q);
}
#endif // !defined(BOOST_ASIO_NO_DEPRECATED)
/// Asynchronously perform forward resolution of a query to a list of entries.
/**
* This function is used to resolve host and service names into a list of
* endpoint entries.
*
* @param host A string identifying a location. May be a descriptive name or
* a numeric address string. If an empty string and the passive flag has been
* specified, the resolved endpoints are suitable for local service binding.
* If an empty string and passive is not specified, the resolved endpoints
* will use the loopback address.
*
* @param service A string identifying the requested service. This may be a
* descriptive name or a numeric string corresponding to a port number. May
* be an empty string, in which case all resolved endpoints will have a port
* number of 0.
*
* @param token The @ref completion_token that will be used to produce a
* completion handler, which will be called when the resolve completes.
* Potential completion tokens include @ref use_future, @ref use_awaitable,
* @ref yield_context, or a function object with the correct completion
* signature. The function signature of the completion handler must be:
* @code void handler(
* const boost::system::error_code& error, // Result of operation.
* resolver::results_type results // Resolved endpoints as a range.
* ); @endcode
* Regardless of whether the asynchronous operation completes immediately or
* not, the completion handler will not be invoked from within this function.
* On immediate completion, invocation of the handler will be performed in a
* manner equivalent to using boost::asio::post().
*
* A successful resolve operation is guaranteed to pass a non-empty range to
* the handler.
*
* @par Completion Signature
* @code void(boost::system::error_code, results_type) @endcode
*
* @note On POSIX systems, host names may be locally defined in the file
* <tt>/etc/hosts</tt>. On Windows, host names may be defined in the file
* <tt>c:\\windows\\system32\\drivers\\etc\\hosts</tt>. Remote host name
* resolution is performed using DNS. Operating systems may use additional
* locations when resolving host names (such as NETBIOS names on Windows).
*
* On POSIX systems, service names are typically defined in the file
* <tt>/etc/services</tt>. On Windows, service names may be found in the file
* <tt>c:\\windows\\system32\\drivers\\etc\\services</tt>. Operating systems
* may use additional locations when resolving service names.
*/
template <
BOOST_ASIO_COMPLETION_TOKEN_FOR(void (boost::system::error_code,
results_type)) ResolveToken = default_completion_token_t<executor_type>>
auto async_resolve(BOOST_ASIO_STRING_VIEW_PARAM host,
BOOST_ASIO_STRING_VIEW_PARAM service,
ResolveToken&& token = default_completion_token_t<executor_type>())
-> decltype(
boost::asio::async_initiate<ResolveToken,
void (boost::system::error_code, results_type)>(
declval<initiate_async_resolve>(), token,
declval<basic_resolver_query<protocol_type>&>()))
{
return async_resolve(host, service, resolver_base::flags(),
static_cast<ResolveToken&&>(token));
}
/// Asynchronously perform forward resolution of a query to a list of entries.
/**
* This function is used to resolve host and service names into a list of
* endpoint entries. It is an initiating function for an @ref
* asynchronous_operation, and always returns immediately.
*
* @param host A string identifying a location. May be a descriptive name or
* a numeric address string. If an empty string and the passive flag has been
* specified, the resolved endpoints are suitable for local service binding.
* If an empty string and passive is not specified, the resolved endpoints
* will use the loopback address.
*
* @param service A string identifying the requested service. This may be a
* descriptive name or a numeric string corresponding to a port number. May
* be an empty string, in which case all resolved endpoints will have a port
* number of 0.
*
* @param resolve_flags A set of flags that determine how name resolution
* should be performed. The default flags are suitable for communication with
* remote hosts. See the @ref resolver_base documentation for the set of
* available flags.
*
* @param token The @ref completion_token that will be used to produce a
* completion handler, which will be called when the resolve completes.
* Potential completion tokens include @ref use_future, @ref use_awaitable,
* @ref yield_context, or a function object with the correct completion
* signature. The function signature of the completion handler must be:
* @code void handler(
* const boost::system::error_code& error, // Result of operation.
* resolver::results_type results // Resolved endpoints as a range.
* ); @endcode
* Regardless of whether the asynchronous operation completes immediately or
* not, the completion handler will not be invoked from within this function.
* On immediate completion, invocation of the handler will be performed in a
* manner equivalent to using boost::asio::post().
*
* A successful resolve operation is guaranteed to pass a non-empty range to
* the handler.
*
* @par Completion Signature
* @code void(boost::system::error_code, results_type) @endcode
*
* @note On POSIX systems, host names may be locally defined in the file
* <tt>/etc/hosts</tt>. On Windows, host names may be defined in the file
* <tt>c:\\windows\\system32\\drivers\\etc\\hosts</tt>. Remote host name
* resolution is performed using DNS. Operating systems may use additional
* locations when resolving host names (such as NETBIOS names on Windows).
*
* On POSIX systems, service names are typically defined in the file
* <tt>/etc/services</tt>. On Windows, service names may be found in the file
* <tt>c:\\windows\\system32\\drivers\\etc\\services</tt>. Operating systems
* may use additional locations when resolving service names.
*/
template <
BOOST_ASIO_COMPLETION_TOKEN_FOR(void (boost::system::error_code,
results_type)) ResolveToken = default_completion_token_t<executor_type>>
auto async_resolve(BOOST_ASIO_STRING_VIEW_PARAM host,
BOOST_ASIO_STRING_VIEW_PARAM service, resolver_base::flags resolve_flags,
ResolveToken&& token = default_completion_token_t<executor_type>())
-> decltype(
boost::asio::async_initiate<ResolveToken,
void (boost::system::error_code, results_type)>(
declval<initiate_async_resolve>(), token,
declval<basic_resolver_query<protocol_type>&>()))
{
basic_resolver_query<protocol_type> q(static_cast<std::string>(host),
static_cast<std::string>(service), resolve_flags);
return boost::asio::async_initiate<ResolveToken,
void (boost::system::error_code, results_type)>(
initiate_async_resolve(this), token, q);
}
/// Asynchronously perform forward resolution of a query to a list of entries.
/**
* This function is used to resolve host and service names into a list of
* endpoint entries. It is an initiating function for an @ref
* asynchronous_operation, and always returns immediately.
*
* @param protocol A protocol object, normally representing either the IPv4 or
* IPv6 version of an internet protocol.
*
* @param host A string identifying a location. May be a descriptive name or
* a numeric address string. If an empty string and the passive flag has been
* specified, the resolved endpoints are suitable for local service binding.
* If an empty string and passive is not specified, the resolved endpoints
* will use the loopback address.
*
* @param service A string identifying the requested service. This may be a
* descriptive name or a numeric string corresponding to a port number. May
* be an empty string, in which case all resolved endpoints will have a port
* number of 0.
*
* @param token The @ref completion_token that will be used to produce a
* completion handler, which will be called when the resolve completes.
* Potential completion tokens include @ref use_future, @ref use_awaitable,
* @ref yield_context, or a function object with the correct completion
* signature. The function signature of the completion handler must be:
* @code void handler(
* const boost::system::error_code& error, // Result of operation.
* resolver::results_type results // Resolved endpoints as a range.
* ); @endcode
* Regardless of whether the asynchronous operation completes immediately or
* not, the completion handler will not be invoked from within this function.
* On immediate completion, invocation of the handler will be performed in a
* manner equivalent to using boost::asio::post().
*
* A successful resolve operation is guaranteed to pass a non-empty range to
* the handler.
*
* @par Completion Signature
* @code void(boost::system::error_code, results_type) @endcode
*
* @note On POSIX systems, host names may be locally defined in the file
* <tt>/etc/hosts</tt>. On Windows, host names may be defined in the file
* <tt>c:\\windows\\system32\\drivers\\etc\\hosts</tt>. Remote host name
* resolution is performed using DNS. Operating systems may use additional
* locations when resolving host names (such as NETBIOS names on Windows).
*
* On POSIX systems, service names are typically defined in the file
* <tt>/etc/services</tt>. On Windows, service names may be found in the file
* <tt>c:\\windows\\system32\\drivers\\etc\\services</tt>. Operating systems
* may use additional locations when resolving service names.
*/
template <
BOOST_ASIO_COMPLETION_TOKEN_FOR(void (boost::system::error_code,
results_type)) ResolveToken = default_completion_token_t<executor_type>>
auto async_resolve(const protocol_type& protocol,
BOOST_ASIO_STRING_VIEW_PARAM host, BOOST_ASIO_STRING_VIEW_PARAM service,
ResolveToken&& token = default_completion_token_t<executor_type>())
-> decltype(
boost::asio::async_initiate<ResolveToken,
void (boost::system::error_code, results_type)>(
declval<initiate_async_resolve>(), token,
declval<basic_resolver_query<protocol_type>&>()))
{
return async_resolve(protocol, host, service, resolver_base::flags(),
static_cast<ResolveToken&&>(token));
}
/// Asynchronously perform forward resolution of a query to a list of entries.
/**
* This function is used to resolve host and service names into a list of
* endpoint entries. It is an initiating function for an @ref
* asynchronous_operation, and always returns immediately.
*
* @param protocol A protocol object, normally representing either the IPv4 or
* IPv6 version of an internet protocol.
*
* @param host A string identifying a location. May be a descriptive name or
* a numeric address string. If an empty string and the passive flag has been
* specified, the resolved endpoints are suitable for local service binding.
* If an empty string and passive is not specified, the resolved endpoints
* will use the loopback address.
*
* @param service A string identifying the requested service. This may be a
* descriptive name or a numeric string corresponding to a port number. May
* be an empty string, in which case all resolved endpoints will have a port
* number of 0.
*
* @param resolve_flags A set of flags that determine how name resolution
* should be performed. The default flags are suitable for communication with
* remote hosts. See the @ref resolver_base documentation for the set of
* available flags.
*
* @param token The @ref completion_token that will be used to produce a
* completion handler, which will be called when the resolve completes.
* Potential completion tokens include @ref use_future, @ref use_awaitable,
* @ref yield_context, or a function object with the correct completion
* signature. The function signature of the completion handler must be:
* @code void handler(
* const boost::system::error_code& error, // Result of operation.
* resolver::results_type results // Resolved endpoints as a range.
* ); @endcode
* Regardless of whether the asynchronous operation completes immediately or
* not, the completion handler will not be invoked from within this function.
* On immediate completion, invocation of the handler will be performed in a
* manner equivalent to using boost::asio::post().
*
* A successful resolve operation is guaranteed to pass a non-empty range to
* the handler.
*
* @par Completion Signature
* @code void(boost::system::error_code, results_type) @endcode
*
* @note On POSIX systems, host names may be locally defined in the file
* <tt>/etc/hosts</tt>. On Windows, host names may be defined in the file
* <tt>c:\\windows\\system32\\drivers\\etc\\hosts</tt>. Remote host name
* resolution is performed using DNS. Operating systems may use additional
* locations when resolving host names (such as NETBIOS names on Windows).
*
* On POSIX systems, service names are typically defined in the file
* <tt>/etc/services</tt>. On Windows, service names may be found in the file
* <tt>c:\\windows\\system32\\drivers\\etc\\services</tt>. Operating systems
* may use additional locations when resolving service names.
*/
template <
BOOST_ASIO_COMPLETION_TOKEN_FOR(void (boost::system::error_code,
results_type)) ResolveToken = default_completion_token_t<executor_type>>
auto async_resolve(const protocol_type& protocol,
BOOST_ASIO_STRING_VIEW_PARAM host, BOOST_ASIO_STRING_VIEW_PARAM service,
resolver_base::flags resolve_flags,
ResolveToken&& token = default_completion_token_t<executor_type>())
-> decltype(
boost::asio::async_initiate<ResolveToken,
void (boost::system::error_code, results_type)>(
declval<initiate_async_resolve>(), token,
declval<basic_resolver_query<protocol_type>&>()))
{
basic_resolver_query<protocol_type> q(
protocol, static_cast<std::string>(host),
static_cast<std::string>(service), resolve_flags);
return boost::asio::async_initiate<ResolveToken,
void (boost::system::error_code, results_type)>(
initiate_async_resolve(this), token, q);
}
/// Perform reverse resolution of an endpoint to a list of entries.
/**
* This function is used to resolve an endpoint into a list of endpoint
* entries.
*
* @param e An endpoint object that determines what endpoints will be
* returned.
*
* @returns A range object representing the list of endpoint entries. A
* successful call to this function is guaranteed to return a non-empty
* range.
*
* @throws boost::system::system_error Thrown on failure.
*/
results_type resolve(const endpoint_type& e)
{
boost::system::error_code ec;
results_type i = impl_.get_service().resolve(
impl_.get_implementation(), e, ec);
boost::asio::detail::throw_error(ec, "resolve");
return i;
}
/// Perform reverse resolution of an endpoint to a list of entries.
/**
* This function is used to resolve an endpoint into a list of endpoint
* entries.
*
* @param e An endpoint object that determines what endpoints will be
* returned.
*
* @param ec Set to indicate what error occurred, if any.
*
* @returns A range object representing the list of endpoint entries. An
* empty range is returned if an error occurs. A successful call to this
* function is guaranteed to return a non-empty range.
*/
results_type resolve(const endpoint_type& e, boost::system::error_code& ec)
{
return impl_.get_service().resolve(impl_.get_implementation(), e, ec);
}
/// Asynchronously perform reverse resolution of an endpoint to a list of
/// entries.
/**
* This function is used to asynchronously resolve an endpoint into a list of
* endpoint entries. It is an initiating function for an @ref
* asynchronous_operation, and always returns immediately.
*
* @param e An endpoint object that determines what endpoints will be
* returned.
*
* @param token The @ref completion_token that will be used to produce a
* completion handler, which will be called when the resolve completes.
* Potential completion tokens include @ref use_future, @ref use_awaitable,
* @ref yield_context, or a function object with the correct completion
* signature. The function signature of the completion handler must be:
* @code void handler(
* const boost::system::error_code& error, // Result of operation.
* resolver::results_type results // Resolved endpoints as a range.
* ); @endcode
* Regardless of whether the asynchronous operation completes immediately or
* not, the completion handler will not be invoked from within this function.
* On immediate completion, invocation of the handler will be performed in a
* manner equivalent to using boost::asio::post().
*
* A successful resolve operation is guaranteed to pass a non-empty range to
* the handler.
*
* @par Completion Signature
* @code void(boost::system::error_code, results_type) @endcode
*/
template <
BOOST_ASIO_COMPLETION_TOKEN_FOR(void (boost::system::error_code,
results_type)) ResolveToken = default_completion_token_t<executor_type>>
auto async_resolve(const endpoint_type& e,
ResolveToken&& token = default_completion_token_t<executor_type>())
-> decltype(
boost::asio::async_initiate<ResolveToken,
void (boost::system::error_code, results_type)>(
declval<initiate_async_resolve>(), token, e))
{
return boost::asio::async_initiate<ResolveToken,
void (boost::system::error_code, results_type)>(
initiate_async_resolve(this), token, e);
}
private:
// Disallow copying and assignment.
basic_resolver(const basic_resolver&) = delete;
basic_resolver& operator=(const basic_resolver&) = delete;
class initiate_async_resolve
{
public:
typedef Executor executor_type;
explicit initiate_async_resolve(basic_resolver* self)
: self_(self)
{
}
executor_type get_executor() const noexcept
{
return self_->get_executor();
}
template <typename ResolveHandler, typename Query>
void operator()(ResolveHandler&& handler,
const Query& q) const
{
// If you get an error on the following line it means that your handler
// does not meet the documented type requirements for a ResolveHandler.
BOOST_ASIO_RESOLVE_HANDLER_CHECK(
ResolveHandler, handler, results_type) type_check;
boost::asio::detail::non_const_lvalue<ResolveHandler> handler2(handler);
self_->impl_.get_service().async_resolve(
self_->impl_.get_implementation(), q,
handler2.value, self_->impl_.get_executor());
}
private:
basic_resolver* self_;
};
# if defined(BOOST_ASIO_WINDOWS_RUNTIME)
boost::asio::detail::io_object_impl<
boost::asio::detail::winrt_resolver_service<InternetProtocol>,
Executor> impl_;
# else
boost::asio::detail::io_object_impl<
boost::asio::detail::resolver_service<InternetProtocol>,
Executor> impl_;
# endif
};
} // namespace ip
} // namespace asio
} // namespace boost
#include <boost/asio/detail/pop_options.hpp>
#endif // BOOST_ASIO_IP_BASIC_RESOLVER_HPP