wip midi

src/midi.c

@@ -16,10 +16,11 @@ void midi_close(MidiDevice device) {
 MidiDevice midi_open(char *name) {
   MidiDevice device;
 
+  device.name = name;
   device.input = NULL;
   device.output = NULL;
 
-  snd_rawmidi_open(&device.input, &device.output, name, 0);
+  snd_rawmidi_open(&device.input, &device.output, name, SND_RAWMIDI_NONBLOCK);
 
   device.error = device.input == NULL || device.output == NULL;
 
@@ -32,5 +33,31 @@ MidiDevice midi_open(char *name) {
   return device;
 }
 
+void midi_background_listen(MidiDevice device, SharedContext *context) {
+  pid_t pid;
+  int bytes_read;
+  unsigned char buffer[3];
+
+  pid = fork();
+  if (pid < 0) {
+    log_error("Could not create subprocess");
+    return;
+  }
+  if (pid == 0) {
+    return;
+  }
+  log_info("(%s) background acquisition started (pid: %d)", device.name, pid);
+
+  while (!context->stop) {
+    bytes_read = snd_rawmidi_read(device.input, buffer, 3);
+    if (bytes_read == 3) {
+      log_debug("midi: %d %.2f", buffer[1], (float)buffer[2] / 256);
+    }
+  }
+
+  log_info("(%s) background acquisition stopped by main thread (pid: %d)",
+           device.name, pid);
+}
+
 // int bytes_read = snd_rawmidi_read(input, input_buffer, sizeof(input_buffer));
 // snd_rawmidi_write(output, buffer, 3);