src/looper.c

@@ -143,10 +143,18 @@ int process_callback(jack_nframes_t nframes, void *arg) {
       continue;
 
     /* Guard against NULL ports (e.g. if port registration failed) */
+    if (active_channels[c].type == CHANNEL_AUDIO) {
       if (!active_channels[c].audio_in || !active_channels[c].audio_out) {
         fprintf(stderr, "WARN: channel %d has NULL audio port(s), skipping\n", c);
         continue;
       }
+    } else {
+      /* CHANNEL_MIDI */
+      if (!active_channels[c].midi_in || !active_channels[c].midi_out) {
+        fprintf(stderr, "WARN: channel %d has NULL MIDI port(s), skipping\n", c);
+        continue;
+      }
+    }
 
     const jack_default_audio_sample_t *in =
         (const jack_default_audio_sample_t *)jack_port_get_buffer(
@@ -507,6 +515,10 @@ void looper_process_commands(jack_client_t *client) {
         jack_port_unregister(client, cur[idx].audio_in);
       if (cur[idx].audio_out)
         jack_port_unregister(client, cur[idx].audio_out);
+      if (cur[idx].midi_in)
+        jack_port_unregister(client, cur[idx].midi_in);
+      if (cur[idx].midi_out)
+        jack_port_unregister(client, cur[idx].midi_out);
       pending_unregister_idx = -1;
     }
   }

src/midi.c

@@ -66,6 +66,10 @@ void midi_handle_events(void *port_buffer, jack_nframes_t nframes) {
               command_t cmd = {.type = CMD_STOP, .channel = -1, .data = 0};
               queue_push(&cmd_queue, cmd);
             } break;
+            case 66: {
+              command_t cmd = {.type = CMD_ADD_MIDI_CHANNEL, .channel = -1, .data = 0};
+              queue_push(&cmd_queue_main_midi, cmd);
+            } break;
             default:
               break;
             }