FIFO_SIZE
if (f->fill >= FIFO_SIZE) {
f->fill = FIFO_SIZE;
f->start = (f->start + 1) % FIFO_SIZE;
f->buf[(f->start + f->fill) % FIFO_SIZE] = *info;
f->start = (f->start + 1) % FIFO_SIZE;
mouse_info_t buf[FIFO_SIZE];