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#include "net/net_helper.h"
namespace epee
{
namespace net_utils
{
boost::unique_future<boost::asio::ip::tcp::socket>
direct_connect::operator()(const std::string& addr, const std::string& port, boost::asio::steady_timer& timeout) const
{
// Get a list of endpoints corresponding to the server name.
//////////////////////////////////////////////////////////////////////////
boost::asio::ip::tcp::resolver resolver(GET_IO_SERVICE(timeout));
boost::asio::ip::tcp::resolver::query query(boost::asio::ip::tcp::v4(), addr, port, boost::asio::ip::tcp::resolver::query::canonical_name);
bool try_ipv6 = false;
boost::asio::ip::tcp::resolver::iterator iterator;
boost::asio::ip::tcp::resolver::iterator end;
boost::system::error_code resolve_error;
try
{
iterator = resolver.resolve(query, resolve_error);
if(iterator == end) // Documentation states that successful call is guaranteed to be non-empty
{
// if IPv4 resolution fails, try IPv6. Unintentional outgoing IPv6 connections should only
// be possible if for some reason a hostname was given and that hostname fails IPv4 resolution,
// so at least for now there should not be a need for a flag "using ipv6 is ok"
try_ipv6 = true;
}
}
catch (const boost::system::system_error& e)
{
if (resolve_error != boost::asio::error::host_not_found &&
resolve_error != boost::asio::error::host_not_found_try_again)
{
throw;
}
try_ipv6 = true;
}
if (try_ipv6)
{
boost::asio::ip::tcp::resolver::query query6(boost::asio::ip::tcp::v6(), addr, port, boost::asio::ip::tcp::resolver::query::canonical_name);
iterator = resolver.resolve(query6);
if (iterator == end)
throw boost::system::system_error{boost::asio::error::fault, "Failed to resolve " + addr};
}
//////////////////////////////////////////////////////////////////////////
struct new_connection
{
boost::promise<boost::asio::ip::tcp::socket> result_;
boost::asio::ip::tcp::socket socket_;
explicit new_connection(boost::asio::io_service& io_service)
: result_(), socket_(io_service)
{}
};
const auto shared = std::make_shared<new_connection>(GET_IO_SERVICE(timeout));
timeout.async_wait([shared] (boost::system::error_code error)
{
if (error != boost::system::errc::operation_canceled && shared && shared->socket_.is_open())
{
shared->socket_.shutdown(boost::asio::ip::tcp::socket::shutdown_both);
shared->socket_.close();
}
});
shared->socket_.async_connect(*iterator, [shared] (boost::system::error_code error)
{
if (shared)
{
if (error)
shared->result_.set_exception(boost::system::system_error{error});
else
shared->result_.set_value(std::move(shared->socket_));
}
});
return shared->result_.get_future();
}
}
}
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