Fix to ensure there are always sample rates and buffer sizes in the dropdown

This can happen if both input and output devices are set to None for instance
on backends that report no supported SR or buffer size for the None device.

diff --git a/gtk2_ardour/engine_dialog.cc b/gtk2_ardour/engine_dialog.cc
index d3c1e14d08eb624d51abb210a9f88905b1fa481c..01450ecb0b3a0b561442e84ed6ef96cb936792b9 100644 (file)
--- a/gtk2_ardour/engine_dialog.cc
+++ b/gtk2_ardour/engine_dialog.cc
@@ -1172,6 +1172,11 @@ EngineControl::set_samplerate_popdown_strings ()
 
        if (_have_control) {
                sr = get_sample_rates_for_all_devices ();
+               // currently possible if both devices are set to "None" and the backend
+               // returns no supported rates for both devices
+               if (sr.empty()) {
+                       sr = get_default_sample_rates ();
+               }
        } else {
                sr = get_default_sample_rates ();
        }
@@ -1257,6 +1262,11 @@ EngineControl::set_buffersize_popdown_strings ()
 
        if (_have_control) {
                bs = get_buffer_sizes_for_all_devices ();
+               // currently possible if both devices are set to "None" and the backend
+               // returns no supported sizes for both devices
+               if (bs.empty()) {
+                       bs = get_default_buffer_sizes ();
+               }
        } else if (backend->can_change_buffer_size_when_running()) {
                bs = get_default_buffer_sizes ();
        }