handleUser method
Implementation
void handleUser(String argument, FtpSession session) {
if (argument.isEmpty) {
session.sendResponse('501 Syntax error in parameters');
return;
}
session.cachedUsername = argument;
session.isAuthenticated = false;
// No credentials configured — log in directly (RFC 959: 230 on USER)
if (session.username == null && session.password == null) {
session.isAuthenticated = true;
session.sendResponse('230 User logged in, proceed');
} else {
session.sendResponse('331 Password required for $argument');
}
}