videotools Code

--- a
+++ b/src/gnet/grequest.h
@@ -0,0 +1,126 @@
+//
+// Copyright (C) 2017 Graeme Walker
+// 
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+// 
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+// 
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+// ===
+///
+/// \file grequest.h
+///
+
+#ifndef G_REQUEST_H
+#define G_REQUEST_H
+
+#include "gdef.h"
+#include "gnet.h"
+#include "gaddress.h"
+#include "gwindow.h"
+
+namespace GNet
+{
+	class Request ;
+	class HostRequest ;
+	class ServiceRequest ;
+}
+
+/// \class GNet::Request
+/// A base class for making asynchronous DNS requests under Windows.
+/// \see WSAAsyncGetHostByName()
+/// 
+class GNet::Request
+{
+protected:
+	enum { magic = 968 } ;
+	int m_magic ;
+	int m_error ;
+	HANDLE m_handle ;
+	char m_buffer[MAXGETHOSTSTRUCT] ;
+	bool m_host ;
+	bool m_done ;
+	bool m_numeric ;
+	GNet::Address m_address ;
+
+protected:
+	explicit Request( bool host ) ;
+		///< Constructor. Derived class constructors 
+		///< should issue the appropriate WSAAsync..()
+		///< request, with m_buffer[] given as the
+		///< result buffer.
+
+public:
+	virtual ~Request() ;
+		///< Virtual destructor. Cancels any
+		///< outstanding request.
+
+	bool valid() const ;
+		///< Returns true if the constructor
+		///< initiated a request properly.
+
+	std::string reason() const ;
+		///< Returns the failure reason if
+		///< valid() or onMessage() returned
+		///< false.
+
+	bool onMessage( WPARAM wparam , LPARAM lparam ) ;
+		///< To be called when the request has
+		///< been completed. Returns false
+		///< on error.
+
+private:
+	Request( const Request & ) ;
+	void operator=( const Request & ) ;
+	static const char *reason( bool host , int error ) ;
+} ;
+
+/// \class GNet::HostRequest
+/// A derivation of GNet::Request used for hostname lookup requests.
+/// 
+class GNet::HostRequest : public Request
+{
+public:
+	HostRequest( std::string host_name , HWND hwnd , unsigned msg ) ;
+		///< Constructor.
+
+	Address result() const ;
+		///< Returns the resolved address with a zero port number.
+
+	std::string fqdn() const ;
+		///< Returns the fully-qualified canonical hostname, if
+		///< available.
+
+private:
+	bool numeric( std::string s , Address & address ) ;
+	HostRequest( const HostRequest & ) ;
+	void operator=( const HostRequest & ) ;
+} ;
+
+/// \class GNet::ServiceRequest
+/// A derivation of GNet::Request used for service (port) lookup requests.
+/// 
+class GNet::ServiceRequest : public Request
+{
+public:
+	ServiceRequest( std::string service_name , bool udp , 
+		HWND hwnd , unsigned msg ) ;
+			///< Constructor.
+
+	Address result() const ;
+		///< Returns the address with a zeroed host part.
+
+private:
+	static const char * protocol( bool udp ) ;
+	bool numeric( std::string s , Address & address ) ;
+} ;
+
+#endif
+