fixed build error

util.cpp

@@ -249,6 +249,11 @@ namespace http
 		}
 	}
 
+	std::string url::portstr_ = "80";
+	unsigned int url::port_ = 80;
+	std::string url::user_ = "";
+	std::string url::pass_ = "";	
+	
 	url::url(const std::string& url_s)
 	{
 		parse(url_s);

util.h

@@ -41,10 +41,10 @@ namespace util
     			void parse(const std::string& url_s);
 			public:
 				std::string protocol_, host_, path_, query_;
-				std::string portstr_ = "80";
+				static std::string portstr_;
-				unsigned int port_ = 80;
+				static unsigned int port_;
-				std::string user_ = "";
+				static std::string user_;
-				std::string pass_ = "";
+				static std::string pass_;
 		};
 	}
 }