Basic relay link connection

common/net/dns.h

@@ -0,0 +1,54 @@
+#pragma once
+
+#include "../event/event_loop.h"
+#include <string>
+#include <functional>
+
+namespace EQ
+{
+	namespace Net
+	{
+		static void DNSLookup(const std::string &addr, int port, bool ipv6, std::function<void(const std::string&)> cb) {
+			struct DNSBaton
+			{
+				std::function<void(const std::string&)> cb;
+				bool ipv6;
+			};
+
+			auto loop = EQ::EventLoop::Get().Handle();
+			uv_getaddrinfo_t *resolver = new uv_getaddrinfo_t();
+			memset(resolver, 0, sizeof(uv_getaddrinfo_t));
+			auto port_str = std::to_string(port);
+			DNSBaton *baton = new DNSBaton();
+			baton->cb = cb;
+			baton->ipv6 = ipv6;
+			resolver->data = baton;
+
+			uv_getaddrinfo(loop, resolver, [](uv_getaddrinfo_t* req, int status, addrinfo* res) {
+				DNSBaton *baton = (DNSBaton*)req->data;
+				if (status < 0) {
+					auto cb = baton->cb;
+					delete baton;
+					delete req;
+					cb("");
+					return;
+				}
+
+				char addr[40] = { 0 };
+
+				if (baton->ipv6) {
+					uv_ip6_name((struct sockaddr_in6*)res->ai_addr, addr, 40);
+				}
+				else {
+					uv_ip4_name((struct sockaddr_in*)res->ai_addr, addr, 40);
+				}
+
+				auto cb = baton->cb;
+				delete baton;
+				delete req;
+				uv_freeaddrinfo(res);
+				cb(addr);
+			}, addr.c_str(), port_str.c_str(), nullptr);
+		}
+	}
+}