flow improvements

source/client.cpp

@@ -30,6 +30,7 @@ static TransferState g_client_state;
 bool isClientTransferDone()        { return g_client_state.done.load(); }
 bool isClientTransferCancelled()   { return g_client_state.cancelled.load(); }
 bool isClientConnectionFailed()    { return g_client_state.connection_failed.load(); }
+bool isClientProgressKnown()       { return g_client_state.bytes_total.load() > 0; }
 void cancelClientTransfer()        { g_client_state.cancelled.store(true); }
 double getClientProgress()         { return g_client_state.progress(); }
 std::string getClientStatusText()  { return g_client_state.getStatus(); }