// // impl/connect.hpp // ~~~~~~~~~~~~~~~~ // // Copyright (c) 2003-2024 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_IMPL_CONNECT_HPP #define ASIO_IMPL_CONNECT_HPP #if defined(_MSC_VER) && (_MSC_VER >= 1200) # pragma once #endif // defined(_MSC_VER) && (_MSC_VER >= 1200) #include <algorithm> #include "asio/associator.hpp" #include "asio/detail/base_from_cancellation_state.hpp" #include "asio/detail/bind_handler.hpp" #include "asio/detail/handler_cont_helpers.hpp" #include "asio/detail/handler_tracking.hpp" #include "asio/detail/handler_type_requirements.hpp" #include "asio/detail/non_const_lvalue.hpp" #include "asio/detail/throw_error.hpp" #include "asio/detail/type_traits.hpp" #include "asio/error.hpp" #include "asio/post.hpp" #include "asio/detail/push_options.hpp" namespace asio { namespace detail { struct default_connect_condition { template <typename Endpoint> bool operator()(const asio::error_code&, const Endpoint&) { return true; } }; template <typename Protocol, typename Iterator> inline typename Protocol::endpoint deref_connect_result( Iterator iter, asio::error_code& ec) { return ec ? typename Protocol::endpoint() : *iter; } template <typename T, typename Iterator> struct legacy_connect_condition_helper : T { typedef char (*fallback_func_type)(...); operator fallback_func_type() const; }; template <typename R, typename Arg1, typename Arg2, typename Iterator> struct legacy_connect_condition_helper<R (*)(Arg1, Arg2), Iterator> { R operator()(Arg1, Arg2) const; char operator()(...) const; }; template <typename T, typename Iterator> struct is_legacy_connect_condition { static char asio_connect_condition_check(char); static char (&asio_connect_condition_check(Iterator))[2]; static const bool value = sizeof(asio_connect_condition_check( (declval<legacy_connect_condition_helper<T, Iterator>>())( declval<const asio::error_code>(), declval<const Iterator>()))) != 1; }; template <typename ConnectCondition, typename Iterator> inline Iterator call_connect_condition(ConnectCondition& connect_condition, const asio::error_code& ec, Iterator next, Iterator end, enable_if_t<is_legacy_connect_condition< ConnectCondition, Iterator>::value>* = 0) { if (next != end) return connect_condition(ec, next); return end; } template <typename ConnectCondition, typename Iterator> inline Iterator call_connect_condition(ConnectCondition& connect_condition, const asio::error_code& ec, Iterator next, Iterator end, enable_if_t<!is_legacy_connect_condition< ConnectCondition, Iterator>::value>* = 0) { for (;next != end; ++next) if (connect_condition(ec, *next)) return next; return end; } } template <typename Protocol, typename Executor, typename EndpointSequence> typename Protocol::endpoint connect(basic_socket<Protocol, Executor>& s, const EndpointSequence& endpoints, constraint_t<is_endpoint_sequence<EndpointSequence>::value>) { asio::error_code ec; typename Protocol::endpoint result = connect(s, endpoints, ec); asio::detail::throw_error(ec, "connect"); return result; } template <typename Protocol, typename Executor, typename EndpointSequence> typename Protocol::endpoint connect(basic_socket<Protocol, Executor>& s, const EndpointSequence& endpoints, asio::error_code& ec, constraint_t<is_endpoint_sequence<EndpointSequence>::value>) { return detail::deref_connect_result<Protocol>( connect(s, endpoints.begin(), endpoints.end(), detail::default_connect_condition(), ec), ec); } #if !defined(ASIO_NO_DEPRECATED) template <typename Protocol, typename Executor, typename Iterator> Iterator connect(basic_socket<Protocol, Executor>& s, Iterator begin, constraint_t<!is_endpoint_sequence<Iterator>::value>) { asio::error_code ec; Iterator result = connect(s, begin, ec); asio::detail::throw_error(ec, "connect"); return result; } template <typename Protocol, typename Executor, typename Iterator> inline Iterator connect(basic_socket<Protocol, Executor>& s, Iterator begin, asio::error_code& ec, constraint_t<!is_endpoint_sequence<Iterator>::value>) { return connect(s, begin, Iterator(), detail::default_connect_condition(), ec); } #endif // !defined(ASIO_NO_DEPRECATED) template <typename Protocol, typename Executor, typename Iterator> Iterator connect(basic_socket<Protocol, Executor>& s, Iterator begin, Iterator end) { asio::error_code ec; Iterator result = connect(s, begin, end, ec); asio::detail::throw_error(ec, "connect"); return result; } template <typename Protocol, typename Executor, typename Iterator> inline Iterator connect(basic_socket<Protocol, Executor>& s, Iterator begin, Iterator end, asio::error_code& ec) { return connect(s, begin, end, detail::default_connect_condition(), ec); } template <typename Protocol, typename Executor, typename EndpointSequence, typename ConnectCondition> typename Protocol::endpoint connect(basic_socket<Protocol, Executor>& s, const EndpointSequence& endpoints, ConnectCondition connect_condition, constraint_t<is_endpoint_sequence<EndpointSequence>::value>) { asio::error_code ec; typename Protocol::endpoint result = connect( s, endpoints, connect_condition, ec); asio::detail::throw_error(ec, "connect"); return result; } template <typename Protocol, typename Executor, typename EndpointSequence, typename ConnectCondition> typename Protocol::endpoint connect(basic_socket<Protocol, Executor>& s, const EndpointSequence& endpoints, ConnectCondition connect_condition, asio::error_code& ec, constraint_t<is_endpoint_sequence<EndpointSequence>::value>) { return detail::deref_connect_result<Protocol>( connect(s, endpoints.begin(), endpoints.end(), connect_condition, ec), ec); } #if !defined(ASIO_NO_DEPRECATED) template <typename Protocol, typename Executor, typename Iterator, typename ConnectCondition> Iterator connect(basic_socket<Protocol, Executor>& s, Iterator begin, ConnectCondition connect_condition, constraint_t<!is_endpoint_sequence<Iterator>::value>) { asio::error_code ec; Iterator result = connect(s, begin, connect_condition, ec); asio::detail::throw_error(ec, "connect"); return result; } template <typename Protocol, typename Executor, typename Iterator, typename ConnectCondition> inline Iterator connect(basic_socket<Protocol, Executor>& s, Iterator begin, ConnectCondition connect_condition, asio::error_code& ec, constraint_t<!is_endpoint_sequence<Iterator>::value>) { return connect(s, begin, Iterator(), connect_condition, ec); } #endif // !defined(ASIO_NO_DEPRECATED) template <typename Protocol, typename Executor, typename Iterator, typename ConnectCondition> Iterator connect(basic_socket<Protocol, Executor>& s, Iterator begin, Iterator end, ConnectCondition connect_condition) { asio::error_code ec; Iterator result = connect(s, begin, end, connect_condition, ec); asio::detail::throw_error(ec, "connect"); return result; } template <typename Protocol, typename Executor, typename Iterator, typename ConnectCondition> Iterator connect(basic_socket<Protocol, Executor>& s, Iterator begin, Iterator end, ConnectCondition connect_condition, asio::error_code& ec) { ec = asio::error_code(); for (Iterator iter = begin; iter != end; ++iter) { iter = (detail::call_connect_condition(connect_condition, ec, iter, end)); if (iter != end) { s.close(ec); s.connect(*iter, ec); if (!ec) return iter; } else break; } if (!ec) ec = asio::error::not_found; return end; } namespace detail { // Enable the empty base class optimisation for the connect condition. template <typename ConnectCondition> class base_from_connect_condition { protected: explicit base_from_connect_condition( const ConnectCondition& connect_condition) : connect_condition_(connect_condition) { } template <typename Iterator> void check_condition(const asio::error_code& ec, Iterator& iter, Iterator& end) { iter = detail::call_connect_condition(connect_condition_, ec, iter, end); } private: ConnectCondition connect_condition_; }; // The default_connect_condition implementation is essentially a no-op. This // template specialisation lets us eliminate all costs associated with it. template <> class base_from_connect_condition<default_connect_condition> { protected: explicit base_from_connect_condition(const default_connect_condition&) { } template <typename Iterator> void check_condition(const asio::error_code&, Iterator&, Iterator&) { } }; template <typename Protocol, typename Executor, typename EndpointSequence, typename ConnectCondition, typename RangeConnectHandler> class range_connect_op : public base_from_cancellation_state<RangeConnectHandler>, base_from_connect_condition<ConnectCondition> { public: range_connect_op(basic_socket<Protocol, Executor>& sock, const EndpointSequence& endpoints, const ConnectCondition& connect_condition, RangeConnectHandler& handler) : base_from_cancellation_state<RangeConnectHandler>( handler, enable_partial_cancellation()), base_from_connect_condition<ConnectCondition>(connect_condition), socket_(sock), endpoints_(endpoints), index_(0), start_(0), handler_(static_cast<RangeConnectHandler&&>(handler)) { } range_connect_op(const range_connect_op& other) : base_from_cancellation_state<RangeConnectHandler>(other), base_from_connect_condition<ConnectCondition>(other), socket_(other.socket_), endpoints_(other.endpoints_), index_(other.index_), start_(other.start_), handler_(other.handler_) { } range_connect_op(range_connect_op&& other) : base_from_cancellation_state<RangeConnectHandler>( static_cast<base_from_cancellation_state<RangeConnectHandler>&&>( other)), base_from_connect_condition<ConnectCondition>(other), socket_(other.socket_), endpoints_(other.endpoints_), index_(other.index_), start_(other.start_), handler_(static_cast<RangeConnectHandler&&>(other.handler_)) { } void operator()(asio::error_code ec, int start = 0) { this->process(ec, start, const_cast<const EndpointSequence&>(endpoints_).begin(), const_cast<const EndpointSequence&>(endpoints_).end()); } //private: template <typename Iterator> void process(asio::error_code ec, int start, Iterator begin, Iterator end) { Iterator iter = begin; std::advance(iter, index_); switch (start_ = start) { case 1: for (;;) { this->check_condition(ec, iter, end); index_ = std::distance(begin, iter); if (iter != end) { socket_.close(ec); ASIO_HANDLER_LOCATION((__FILE__, __LINE__, "async_connect")); socket_.async_connect(*iter, static_cast<range_connect_op&&>(*this)); return; } if (start) { ec = asio::error::not_found; ASIO_HANDLER_LOCATION((__FILE__, __LINE__, "async_connect")); asio::post(socket_.get_executor(), detail::bind_handler( static_cast<range_connect_op&&>(*this), ec)); return; } /* fall-through */ default: if (iter == end) break; if (!socket_.is_open()) { ec = asio::error::operation_aborted; break; } if (!ec) break; if (this->cancelled() != cancellation_type::none) { ec = asio::error::operation_aborted; break; } ++iter; ++index_; } static_cast<RangeConnectHandler&&>(handler_)( static_cast<const asio::error_code&>(ec), static_cast<const typename Protocol::endpoint&>( ec || iter == end ? typename Protocol::endpoint() : *iter)); } } basic_socket<Protocol, Executor>& socket_; EndpointSequence endpoints_; std::size_t index_; int start_; RangeConnectHandler handler_; }; template <typename Protocol, typename Executor, typename EndpointSequence, typename ConnectCondition, typename RangeConnectHandler> inline bool asio_handler_is_continuation( range_connect_op<Protocol, Executor, EndpointSequence, ConnectCondition, RangeConnectHandler>* this_handler) { return asio_handler_cont_helpers::is_continuation( this_handler->handler_); } template <typename Protocol, typename Executor> class initiate_async_range_connect { public: typedef Executor executor_type; explicit initiate_async_range_connect(basic_socket<Protocol, Executor>& s) : socket_(s) { } executor_type get_executor() const noexcept { return socket_.get_executor(); } template <typename RangeConnectHandler, typename EndpointSequence, typename ConnectCondition> void operator()(RangeConnectHandler&& handler, const EndpointSequence& endpoints, const ConnectCondition& connect_condition) const { // If you get an error on the following line it means that your // handler does not meet the documented type requirements for an // RangeConnectHandler. ASIO_RANGE_CONNECT_HANDLER_CHECK(RangeConnectHandler, handler, typename Protocol::endpoint) type_check; non_const_lvalue<RangeConnectHandler> handler2(handler); range_connect_op<Protocol, Executor, EndpointSequence, ConnectCondition, decay_t<RangeConnectHandler>>(socket_, endpoints, connect_condition, handler2.value)(asio::error_code(), 1); } private: basic_socket<Protocol, Executor>& socket_; }; template <typename Protocol, typename Executor, typename Iterator, typename ConnectCondition, typename IteratorConnectHandler> class iterator_connect_op : public base_from_cancellation_state<IteratorConnectHandler>, base_from_connect_condition<ConnectCondition> { public: iterator_connect_op(basic_socket<Protocol, Executor>& sock, const Iterator& begin, const Iterator& end, const ConnectCondition& connect_condition, IteratorConnectHandler& handler) : base_from_cancellation_state<IteratorConnectHandler>( handler, enable_partial_cancellation()), base_from_connect_condition<ConnectCondition>(connect_condition), socket_(sock), iter_(begin), end_(end), start_(0), handler_(static_cast<IteratorConnectHandler&&>(handler)) { } iterator_connect_op(const iterator_connect_op& other) : base_from_cancellation_state<IteratorConnectHandler>(other), base_from_connect_condition<ConnectCondition>(other), socket_(other.socket_), iter_(other.iter_), end_(other.end_), start_(other.start_), handler_(other.handler_) { } iterator_connect_op(iterator_connect_op&& other) : base_from_cancellation_state<IteratorConnectHandler>( static_cast<base_from_cancellation_state<IteratorConnectHandler>&&>( other)), base_from_connect_condition<ConnectCondition>(other), socket_(other.socket_), iter_(other.iter_), end_(other.end_), start_(other.start_), handler_(static_cast<IteratorConnectHandler&&>(other.handler_)) { } void operator()(asio::error_code ec, int start = 0) { switch (start_ = start) { case 1: for (;;) { this->check_condition(ec, iter_, end_); if (iter_ != end_) { socket_.close(ec); ASIO_HANDLER_LOCATION((__FILE__, __LINE__, "async_connect")); socket_.async_connect(*iter_, static_cast<iterator_connect_op&&>(*this)); return; } if (start) { ec = asio::error::not_found; ASIO_HANDLER_LOCATION((__FILE__, __LINE__, "async_connect")); asio::post(socket_.get_executor(), detail::bind_handler( static_cast<iterator_connect_op&&>(*this), ec)); return; } /* fall-through */ default: if (iter_ == end_) break; if (!socket_.is_open()) { ec = asio::error::operation_aborted; break; } if (!ec) break; if (this->cancelled() != cancellation_type::none) { ec = asio::error::operation_aborted; break; } ++iter_; } static_cast<IteratorConnectHandler&&>(handler_)( static_cast<const asio::error_code&>(ec), static_cast<const Iterator&>(iter_)); } } //private: basic_socket<Protocol, Executor>& socket_; Iterator iter_; Iterator end_; int start_; IteratorConnectHandler handler_; }; template <typename Protocol, typename Executor, typename Iterator, typename ConnectCondition, typename IteratorConnectHandler> inline bool asio_handler_is_continuation( iterator_connect_op<Protocol, Executor, Iterator, ConnectCondition, IteratorConnectHandler>* this_handler) { return asio_handler_cont_helpers::is_continuation( this_handler->handler_); } template <typename Protocol, typename Executor> class initiate_async_iterator_connect { public: typedef Executor executor_type; explicit initiate_async_iterator_connect( basic_socket<Protocol, Executor>& s) : socket_(s) { } executor_type get_executor() const noexcept { return socket_.get_executor(); } template <typename IteratorConnectHandler, typename Iterator, typename ConnectCondition> void operator()(IteratorConnectHandler&& handler, Iterator begin, Iterator end, const ConnectCondition& connect_condition) const { // If you get an error on the following line it means that your // handler does not meet the documented type requirements for an // IteratorConnectHandler. ASIO_ITERATOR_CONNECT_HANDLER_CHECK( IteratorConnectHandler, handler, Iterator) type_check; non_const_lvalue<IteratorConnectHandler> handler2(handler); iterator_connect_op<Protocol, Executor, Iterator, ConnectCondition, decay_t<IteratorConnectHandler>>(socket_, begin, end, connect_condition, handler2.value)(asio::error_code(), 1); } private: basic_socket<Protocol, Executor>& socket_; }; } // namespace detail #if !defined(GENERATING_DOCUMENTATION) template <template <typename, typename> class Associator, typename Protocol, typename Executor, typename EndpointSequence, typename ConnectCondition, typename RangeConnectHandler, typename DefaultCandidate> struct associator<Associator, detail::range_connect_op<Protocol, Executor, EndpointSequence, ConnectCondition, RangeConnectHandler>, DefaultCandidate> : Associator<RangeConnectHandler, DefaultCandidate> { static typename Associator<RangeConnectHandler, DefaultCandidate>::type get( const detail::range_connect_op<Protocol, Executor, EndpointSequence, ConnectCondition, RangeConnectHandler>& h) noexcept { return Associator<RangeConnectHandler, DefaultCandidate>::get(h.handler_); } static auto get( const detail::range_connect_op<Protocol, Executor, EndpointSequence, ConnectCondition, RangeConnectHandler>& h, const DefaultCandidate& c) noexcept -> decltype( Associator<RangeConnectHandler, DefaultCandidate>::get( h.handler_, c)) { return Associator<RangeConnectHandler, DefaultCandidate>::get( h.handler_, c); } }; template <template <typename, typename> class Associator, typename Protocol, typename Executor, typename Iterator, typename ConnectCondition, typename IteratorConnectHandler, typename DefaultCandidate> struct associator<Associator, detail::iterator_connect_op<Protocol, Executor, Iterator, ConnectCondition, IteratorConnectHandler>, DefaultCandidate> : Associator<IteratorConnectHandler, DefaultCandidate> { static typename Associator<IteratorConnectHandler, DefaultCandidate>::type get(const detail::iterator_connect_op<Protocol, Executor, Iterator, ConnectCondition, IteratorConnectHandler>& h) noexcept { return Associator<IteratorConnectHandler, DefaultCandidate>::get( h.handler_); } static auto get( const detail::iterator_connect_op<Protocol, Executor, Iterator, ConnectCondition, IteratorConnectHandler>& h, const DefaultCandidate& c) noexcept -> decltype( Associator<IteratorConnectHandler, DefaultCandidate>::get( h.handler_, c)) { return Associator<IteratorConnectHandler, DefaultCandidate>::get( h.handler_, c); } }; #endif // !defined(GENERATING_DOCUMENTATION) template <typename Protocol, typename Executor, typename EndpointSequence, ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code, typename Protocol::endpoint)) RangeConnectToken> inline auto async_connect(basic_socket<Protocol, Executor>& s, const EndpointSequence& endpoints, RangeConnectToken&& token, constraint_t<is_endpoint_sequence<EndpointSequence>::value>) -> decltype( async_initiate<RangeConnectToken, void (asio::error_code, typename Protocol::endpoint)>( declval<detail::initiate_async_range_connect<Protocol, Executor>>(), token, endpoints, declval<detail::default_connect_condition>())) { return async_initiate<RangeConnectToken, void (asio::error_code, typename Protocol::endpoint)>( detail::initiate_async_range_connect<Protocol, Executor>(s), token, endpoints, detail::default_connect_condition()); } #if !defined(ASIO_NO_DEPRECATED) template <typename Protocol, typename Executor, typename Iterator, ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code, Iterator)) IteratorConnectToken> inline auto async_connect(basic_socket<Protocol, Executor>& s, Iterator begin, IteratorConnectToken&& token, constraint_t<!is_endpoint_sequence<Iterator>::value>) -> decltype( async_initiate<IteratorConnectToken, void (asio::error_code, Iterator)>( declval<detail::initiate_async_iterator_connect<Protocol, Executor>>(), token, begin, Iterator(), declval<detail::default_connect_condition>())) { return async_initiate<IteratorConnectToken, void (asio::error_code, Iterator)>( detail::initiate_async_iterator_connect<Protocol, Executor>(s), token, begin, Iterator(), detail::default_connect_condition()); } #endif // !defined(ASIO_NO_DEPRECATED) template <typename Protocol, typename Executor, typename Iterator, ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code, Iterator)) IteratorConnectToken> inline auto async_connect(basic_socket<Protocol, Executor>& s, Iterator begin, Iterator end, IteratorConnectToken&& token) -> decltype( async_initiate<IteratorConnectToken, void (asio::error_code, Iterator)>( declval<detail::initiate_async_iterator_connect<Protocol, Executor>>(), token, begin, end, declval<detail::default_connect_condition>())) { return async_initiate<IteratorConnectToken, void (asio::error_code, Iterator)>( detail::initiate_async_iterator_connect<Protocol, Executor>(s), token, begin, end, detail::default_connect_condition()); } template <typename Protocol, typename Executor, typename EndpointSequence, typename ConnectCondition, ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code, typename Protocol::endpoint)) RangeConnectToken> inline auto async_connect(basic_socket<Protocol, Executor>& s, const EndpointSequence& endpoints, ConnectCondition connect_condition, RangeConnectToken&& token, constraint_t<is_endpoint_sequence<EndpointSequence>::value>) -> decltype( async_initiate<RangeConnectToken, void (asio::error_code, typename Protocol::endpoint)>( declval<detail::initiate_async_range_connect<Protocol, Executor>>(), token, endpoints, connect_condition)) { return async_initiate<RangeConnectToken, void (asio::error_code, typename Protocol::endpoint)>( detail::initiate_async_range_connect<Protocol, Executor>(s), token, endpoints, connect_condition); } #if !defined(ASIO_NO_DEPRECATED) template <typename Protocol, typename Executor, typename Iterator, typename ConnectCondition, ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code, Iterator)) IteratorConnectToken> inline auto async_connect(basic_socket<Protocol, Executor>& s, Iterator begin, ConnectCondition connect_condition, IteratorConnectToken&& token, constraint_t<!is_endpoint_sequence<Iterator>::value>) -> decltype( async_initiate<IteratorConnectToken, void (asio::error_code, Iterator)>( declval<detail::initiate_async_iterator_connect<Protocol, Executor>>(), token, begin, Iterator(), connect_condition)) { return async_initiate<IteratorConnectToken, void (asio::error_code, Iterator)>( detail::initiate_async_iterator_connect<Protocol, Executor>(s), token, begin, Iterator(), connect_condition); } #endif // !defined(ASIO_NO_DEPRECATED) template <typename Protocol, typename Executor, typename Iterator, typename ConnectCondition, ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code, Iterator)) IteratorConnectToken> inline auto async_connect(basic_socket<Protocol, Executor>& s, Iterator begin, Iterator end, ConnectCondition connect_condition, IteratorConnectToken&& token) -> decltype( async_initiate<IteratorConnectToken, void (asio::error_code, Iterator)>( declval<detail::initiate_async_iterator_connect<Protocol, Executor>>(), token, begin, end, connect_condition)) { return async_initiate<IteratorConnectToken, void (asio::error_code, Iterator)>( detail::initiate_async_iterator_connect<Protocol, Executor>(s), token, begin, end, connect_condition); } } // namespace asio #include "asio/detail/pop_options.hpp" #endif // ASIO_IMPL_CONNECT_HPP