feat: auto-reconnect midi

src/midi.c

@@ -13,14 +13,17 @@ void midi_open(MidiDevice *device, const char *name) {
 
   snd_rawmidi_open(&device->input, &device->output, name, SND_RAWMIDI_NONBLOCK);
 
-  device->error = device->input == NULL || device->output == NULL;
+  device->connected = device->input != NULL && device->output != NULL;
 
-  log_info("(%s) MIDI open", name);
+  if (device->connected) {
+    log_info("(%s) MIDI open", name);
+  } else {
+    log_warn("(%s) MIDI open failed", name);
+  }
 }
 
-void midi_write(const MidiDevice *device, unsigned char code,
-                unsigned char value) {
-  if (device->error) {
+void midi_write(MidiDevice device, unsigned char code, unsigned char value) {
+  if (!device.connected) {
     return;
   }
 
@@ -30,7 +33,15 @@ void midi_write(const MidiDevice *device, unsigned char code,
   buffer[1] = code;
   buffer[2] = value;
 
-  snd_rawmidi_write(device->output, buffer, 3);
+  snd_rawmidi_write(device.output, buffer, 3);
+}
+
+void midi_close(MidiDevice *device) {
+  if (device->connected) {
+    snd_rawmidi_close(device->input);
+    snd_rawmidi_close(device->output);
+    device->connected = false;
+  }
 }
 
 void *midi_background_listen(void *args) {
@@ -39,17 +50,28 @@ void *midi_background_listen(void *args) {
   Context *context = process_args->context;
 
   int bytes_read;
+  snd_rawmidi_info_t *info;
   unsigned char buffer[3];
 
   log_info("(%s) background acquisition started", device->name);
 
-  while (!context->stop) {
+  snd_rawmidi_info_malloc(&info);
+
+  while (!context->stop && snd_rawmidi_info(device->output, info) == 0) {
     bytes_read = snd_rawmidi_read(device->input, buffer, 3);
     if (bytes_read == 3) {
       process_args->event_callback(buffer[1], buffer[2]);
     }
   }
 
-  log_info("(%s) background acquisition stopped by main thread", device->name);
+  snd_rawmidi_info_free(info);
+
+  if (context->stop) {
+    log_info("(%s) background acquisition stopped by main thread",
+             device->name);
+  } else {
+    log_info("(%s) background acquisition stopped after error", device->name);
+    midi_close(device);
+  }
   pthread_exit(NULL);
 }