basic_resolver.hpp

//
// ip/basic_resolver.hpp
// ~~~~~~~~~~~~~~~~~~~~~
//
// Copyright (c) 2003-2020 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_IP_BASIC_RESOLVER_HPP
#define ASIO_IP_BASIC_RESOLVER_HPP

#if defined(_MSC_VER) && (_MSC_VER >= 1200)
# pragma once
#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)

#include "asio/detail/config.hpp"
#include <string>
#include "asio/any_io_executor.hpp"
#include "asio/async_result.hpp"
#include "asio/detail/handler_type_requirements.hpp"
#include "asio/detail/io_object_impl.hpp"
#include "asio/detail/non_const_lvalue.hpp"
#include "asio/detail/string_view.hpp"
#include "asio/detail/throw_error.hpp"
#include "asio/error.hpp"
#include "asio/execution_context.hpp"
#include "asio/ip/basic_resolver_iterator.hpp"
#include "asio/ip/basic_resolver_query.hpp"
#include "asio/ip/basic_resolver_results.hpp"
#include "asio/ip/resolver_base.hpp"
#if defined(ASIO_WINDOWS_RUNTIME)
# include "asio/detail/winrt_resolver_service.hpp"
#else
# include "asio/detail/resolver_service.hpp"
#endif

#if defined(ASIO_HAS_MOVE)
# include <utility>
#endif // defined(ASIO_HAS_MOVE)

#include "asio/detail/push_options.hpp"

namespace asio {
namespace ip {

#if !defined(ASIO_IP_BASIC_RESOLVER_FWD_DECL)
#define ASIO_IP_BASIC_RESOLVER_FWD_DECL

// Forward declaration with defaulted arguments.
template <typename InternetProtocol, typename Executor = any_io_executor>
class basic_resolver;

#endif // !defined(ASIO_IP_BASIC_RESOLVER_FWD_DECL)


template <typename InternetProtocol, typename Executor>
class basic_resolver
  : public resolver_base
{
public:
  typedef Executor executor_type;

  template <typename Executor1>
  struct rebind_executor
  {
    typedef basic_resolver<InternetProtocol, Executor1> other;
  };

  typedef InternetProtocol protocol_type;

  typedef typename InternetProtocol::endpoint endpoint_type;

#if !defined(ASIO_NO_DEPRECATED)
  typedef basic_resolver_query<InternetProtocol> query;

  typedef basic_resolver_iterator<InternetProtocol> iterator;
#endif // !defined(ASIO_NO_DEPRECATED)

  typedef basic_resolver_results<InternetProtocol> results_type;


  explicit basic_resolver(const executor_type& ex)
    : impl_(ex)
  {
  }


  template <typename ExecutionContext>
  explicit basic_resolver(ExecutionContext& context,
      typename enable_if<
        is_convertible<ExecutionContext&, execution_context&>::value
      >::type* = 0)
    : impl_(context)
  {
  }

#if defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)

  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;


  template <typename Executor1>
  basic_resolver(basic_resolver<InternetProtocol, Executor1>&& other,
      typename enable_if<
          is_convertible<Executor1, Executor>::value
      >::type* = 0)
    : impl_(std::move(other.impl_))
  {
  }


  basic_resolver& operator=(basic_resolver&& other)
  {
    impl_ = std::move(other.impl_);
    return *this;
  }


  template <typename Executor1>
  typename enable_if<
    is_convertible<Executor1, Executor>::value,
    basic_resolver&
  >::type operator=(basic_resolver<InternetProtocol, Executor1>&& other)
  {
    basic_resolver tmp(std::move(other));
    impl_ = std::move(tmp.impl_);
    return *this;
  }
#endif // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)


  ~basic_resolver()
  {
  }

  executor_type get_executor() ASIO_NOEXCEPT
  {
    return impl_.get_executor();
  }


  void cancel()
  {
    return impl_.get_service().cancel(impl_.get_implementation());
  }

#if !defined(ASIO_NO_DEPRECATED)

  results_type resolve(const query& q)
  {
    asio::error_code ec;
    results_type r = impl_.get_service().resolve(
        impl_.get_implementation(), q, ec);
    asio::detail::throw_error(ec, "resolve");
    return r;
  }


  results_type resolve(const query& q, asio::error_code& ec)
  {
    return impl_.get_service().resolve(impl_.get_implementation(), q, ec);
  }
#endif // !defined(ASIO_NO_DEPRECATED)


  results_type resolve(ASIO_STRING_VIEW_PARAM host,
      ASIO_STRING_VIEW_PARAM service)
  {
    return resolve(host, service, resolver_base::flags());
  }


  results_type resolve(ASIO_STRING_VIEW_PARAM host,
      ASIO_STRING_VIEW_PARAM service, asio::error_code& ec)
  {
    return resolve(host, service, resolver_base::flags(), ec);
  }


  results_type resolve(ASIO_STRING_VIEW_PARAM host,
      ASIO_STRING_VIEW_PARAM service, resolver_base::flags resolve_flags)
  {
    asio::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);
    asio::detail::throw_error(ec, "resolve");
    return r;
  }


  results_type resolve(ASIO_STRING_VIEW_PARAM host,
      ASIO_STRING_VIEW_PARAM service, resolver_base::flags resolve_flags,
      asio::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);
  }


  results_type resolve(const protocol_type& protocol,
      ASIO_STRING_VIEW_PARAM host, ASIO_STRING_VIEW_PARAM service)
  {
    return resolve(protocol, host, service, resolver_base::flags());
  }


  results_type resolve(const protocol_type& protocol,
      ASIO_STRING_VIEW_PARAM host, ASIO_STRING_VIEW_PARAM service,
      asio::error_code& ec)
  {
    return resolve(protocol, host, service, resolver_base::flags(), ec);
  }


  results_type resolve(const protocol_type& protocol,
      ASIO_STRING_VIEW_PARAM host, ASIO_STRING_VIEW_PARAM service,
      resolver_base::flags resolve_flags)
  {
    asio::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);
    asio::detail::throw_error(ec, "resolve");
    return r;
  }


  results_type resolve(const protocol_type& protocol,
      ASIO_STRING_VIEW_PARAM host, ASIO_STRING_VIEW_PARAM service,
      resolver_base::flags resolve_flags, asio::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(ASIO_NO_DEPRECATED)

  template <
      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
        results_type)) ResolveHandler
          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
  ASIO_INITFN_AUTO_RESULT_TYPE(ResolveHandler,
      void (asio::error_code, results_type))
  async_resolve(const query& q,
      ASIO_MOVE_ARG(ResolveHandler) handler
        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
  {
    return asio::async_initiate<ResolveHandler,
      void (asio::error_code, results_type)>(
        initiate_async_resolve(this), handler, q);
  }
#endif // !defined(ASIO_NO_DEPRECATED)


  template <
      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
        results_type)) ResolveHandler
          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
  ASIO_INITFN_AUTO_RESULT_TYPE(ResolveHandler,
      void (asio::error_code, results_type))
  async_resolve(ASIO_STRING_VIEW_PARAM host,
      ASIO_STRING_VIEW_PARAM service,
      ASIO_MOVE_ARG(ResolveHandler) handler
        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
  {
    return async_resolve(host, service, resolver_base::flags(),
        ASIO_MOVE_CAST(ResolveHandler)(handler));
  }


  template <
      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
        results_type)) ResolveHandler
          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
  ASIO_INITFN_AUTO_RESULT_TYPE(ResolveHandler,
      void (asio::error_code, results_type))
  async_resolve(ASIO_STRING_VIEW_PARAM host,
      ASIO_STRING_VIEW_PARAM service,
      resolver_base::flags resolve_flags,
      ASIO_MOVE_ARG(ResolveHandler) handler
        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
  {
    basic_resolver_query<protocol_type> q(static_cast<std::string>(host),
        static_cast<std::string>(service), resolve_flags);

    return asio::async_initiate<ResolveHandler,
      void (asio::error_code, results_type)>(
        initiate_async_resolve(this), handler, q);
  }


  template <
      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
        results_type)) ResolveHandler
          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
  ASIO_INITFN_AUTO_RESULT_TYPE(ResolveHandler,
      void (asio::error_code, results_type))
  async_resolve(const protocol_type& protocol,
      ASIO_STRING_VIEW_PARAM host, ASIO_STRING_VIEW_PARAM service,
      ASIO_MOVE_ARG(ResolveHandler) handler
        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
  {
    return async_resolve(protocol, host, service, resolver_base::flags(),
        ASIO_MOVE_CAST(ResolveHandler)(handler));
  }


  template <
      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
        results_type)) ResolveHandler
          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
  ASIO_INITFN_AUTO_RESULT_TYPE(ResolveHandler,
      void (asio::error_code, results_type))
  async_resolve(const protocol_type& protocol,
      ASIO_STRING_VIEW_PARAM host, ASIO_STRING_VIEW_PARAM service,
      resolver_base::flags resolve_flags,
      ASIO_MOVE_ARG(ResolveHandler) handler
        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
  {
    basic_resolver_query<protocol_type> q(
        protocol, static_cast<std::string>(host),
        static_cast<std::string>(service), resolve_flags);

    return asio::async_initiate<ResolveHandler,
      void (asio::error_code, results_type)>(
        initiate_async_resolve(this), handler, q);
  }


  results_type resolve(const endpoint_type& e)
  {
    asio::error_code ec;
    results_type i = impl_.get_service().resolve(
        impl_.get_implementation(), e, ec);
    asio::detail::throw_error(ec, "resolve");
    return i;
  }


  results_type resolve(const endpoint_type& e, asio::error_code& ec)
  {
    return impl_.get_service().resolve(impl_.get_implementation(), e, ec);
  }


  template <
      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
        results_type)) ResolveHandler
          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
  ASIO_INITFN_AUTO_RESULT_TYPE(ResolveHandler,
      void (asio::error_code, results_type))
  async_resolve(const endpoint_type& e,
      ASIO_MOVE_ARG(ResolveHandler) handler
        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
  {
    return asio::async_initiate<ResolveHandler,
      void (asio::error_code, results_type)>(
        initiate_async_resolve(this), handler, e);
  }

private:
  // Disallow copying and assignment.
  basic_resolver(const basic_resolver&) ASIO_DELETED;
  basic_resolver& operator=(const basic_resolver&) ASIO_DELETED;

  class initiate_async_resolve
  {
  public:
    typedef Executor executor_type;

    explicit initiate_async_resolve(basic_resolver* self)
      : self_(self)
    {
    }

    executor_type get_executor() const ASIO_NOEXCEPT
    {
      return self_->get_executor();
    }

    template <typename ResolveHandler, typename Query>
    void operator()(ASIO_MOVE_ARG(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.
      ASIO_RESOLVE_HANDLER_CHECK(
          ResolveHandler, handler, results_type) type_check;

      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(ASIO_WINDOWS_RUNTIME)
  asio::detail::io_object_impl<
    asio::detail::winrt_resolver_service<InternetProtocol>,
    Executor> impl_;
# else
  asio::detail::io_object_impl<
    asio::detail::resolver_service<InternetProtocol>,
    Executor> impl_;
# endif
};

} // namespace ip
} // namespace asio

#include "asio/detail/pop_options.hpp"

#endif // ASIO_IP_BASIC_RESOLVER_HPP