Function waitForInterrupt2

wiringPi/wiringPi.c:2636–2784

 */

struct WPIWfiStatus waitForInterrupt2(int pin, int edgeMode, int ms, unsigned long debounce_period_us)    // ms < 0 wait infinite, = 0 return immediately, > 0 wait timeout
{
  int ret;
  int fd, attr, status, readret;
  struct pollfd polls ;
  struct gpio_v2_line_event evdata;
  struct gpio_v2_line_config config;
  struct gpio_v2_line_request req;
  const char* strmode = "";
  struct WPIWfiStatus wfiStatus;
  
  memset(&wfiStatus, 0, sizeof(wfiStatus));
  /* open gpio */
  if (wiringPiGpioDeviceGetFd()<0 || !ToBCMPin(&pin)) {
    wfiStatus.statusOK = -1;
    return wfiStatus;
  }
  
  memset(&req, 0, sizeof(req));
  memset(&config, 0, sizeof(config));
  
  /* setup config */
  config.flags = GPIO_V2_LINE_FLAG_INPUT;
  
  switch(edgeMode) {
    default:
    case INT_EDGE_SETUP:
      if (wiringPiDebug) {
        printf ("waitForInterrupt2: edgeMode INT_EDGE_SETUP - exiting\n") ;
      }
      wfiStatus.statusOK = -1;
      return wfiStatus;
    case INT_EDGE_FALLING:
      config.flags |= GPIO_V2_LINE_FLAG_EDGE_FALLING;
      strmode = "falling";
      break;
    case INT_EDGE_RISING:
      config.flags |= GPIO_V2_LINE_FLAG_EDGE_RISING;
      strmode = "rising";
      break;
    case INT_EDGE_BOTH:
      config.flags |= (GPIO_V2_LINE_FLAG_EDGE_FALLING | GPIO_V2_LINE_FLAG_EDGE_RISING);
      strmode = "both";
      break;
  }
  strcpy(req.consumer, "wiringpi_gpio_irq");
  
  if (debounce_period_us) {
	  attr = config.num_attrs;
	  config.num_attrs++;
    gpiotools_set_bit(&config.attrs[attr].mask, 0);
	  config.attrs[attr].attr.id = GPIO_V2_LINE_ATTR_ID_DEBOUNCE;
	  config.attrs[attr].attr.debounce_period_us = debounce_period_us;
  }
  
  req.num_lines = 1;
  req.offsets[0] = pin;
  req.event_buffer_size = 32;