The test for additional switches to the LIST command

must be performed before the path is joined. Otherwise,
the path will never be empty and the test will be skipped.
Fixes ENODEV error (FTP/550) on clients using "LIST -a".

source/ftpSession.cpp

@@ -1230,26 +1230,27 @@ void FtpSession::xferDir (char const *const args_, XferDirMode const mode_, bool
 	if (std::strlen (args_) > 0)
 	{
 		// an argument was provided
-		auto const path = buildResolvedPath (m_cwd, args_);
-		if (path.empty ())
+
+		// work around broken clients that think LIST -a/-l is valid
+		if (workaround_)
 		{
-			// work around broken clients that think LIST -a/-l is valid
-			if (workaround_)
+			if (args_[0] == '-' && (args_[1] == 'a' || args_[1] == 'l'))
 			{
-				if (args_[0] == '-' && (args_[1] == 'a' || args_[1] == 'l'))
+				char const *args = &args_[2];
+				if (*args == '\0' || *args == ' ')
 				{
-					char const *args = &args_[2];
-					if (*args == '\0' || *args == ' ')
-					{
-						if (*args == ' ')
-							++args;
+					if (*args == ' ')
+						++args;
 
-						xferDir (args, mode_, false);
-						return;
-					}
+					xferDir (args, mode_, false);
+					return;
 				}
 			}
+		}
 
+		auto const path = buildResolvedPath (m_cwd, args_);
+		if (path.empty ())
+		{
 			sendResponse ("550 %s\r\n", std::strerror (errno));
 			setState (State::COMMAND, true, true);
 			return;