#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <stdio.h>
#include <errno.h>
#include <signal.h>

#include <libusb-1.0/libusb.h>

#define EP_DATA_IN	0x82

static struct libusb_device_handle *devh = NULL;

static unsigned int num_bytes = 0, num_xfer = 0;
static struct timeval tv_start;

static void cb_xfr(struct libusb_transfer *xfr)
{
	if (xfr->status != LIBUSB_TRANSFER_COMPLETED) {
		fprintf(stderr, "transfer status %d\n", xfr->status);
		libusb_free_transfer(xfr);
		exit(3);
	}

	//printf("length:%u, actual_length:%u\n", xfr->length, xfr->actual_length);
	num_bytes += xfr->length;
	num_xfer++;

	if (libusb_submit_transfer(xfr) < 0) {
		fprintf(stderr, "error re-submitting URB\n");
		exit(1);
	}

}

static int benchmark_in(void)
{
	static uint8_t buf[2048];
	static struct libusb_transfer *xfr;

	xfr = libusb_alloc_transfer(0);
	if (!xfr)
		return -ENOMEM;

	libusb_fill_bulk_transfer(xfr, devh, EP_DATA_IN, buf,
				sizeof(buf), cb_xfr, NULL, 0);

	gettimeofday(&tv_start, NULL);
	return libusb_submit_transfer(xfr);
}

static void measure(void)
{
	struct timeval tv_stop;
	unsigned int diff_msec;

	gettimeofday(&tv_stop, NULL);

	diff_msec = (tv_stop.tv_sec - tv_start.tv_sec)*1000;
	diff_msec += (tv_stop.tv_usec - tv_start.tv_usec)/1000;

	printf("%u transfers (total %u bytes) in %u miliseconds => %u bytes/sec\n",
		num_xfer, num_bytes, diff_msec, (num_bytes*1000)/diff_msec);
}

static void sig_hdlr(int signum)
{
	switch (signum) {
	case SIGINT:
		measure();
		exit(0);
		break;
	}
}

int main(int argc, char **argv)
{
	int rc;

	signal(SIGINT, &sig_hdlr);

	rc = libusb_init(NULL);
	if (rc < 0) {
		fprintf(stderr, "Error initializing libusb\n");
		exit(1);
	}

	devh = libusb_open_device_with_vid_pid(NULL, 0x16c0, 0x0763);
	if (!devh) {
		fprintf(stderr, "Error finding USB device\n");
		exit(1);
	}

	rc = libusb_claim_interface(devh, 0);
	if (rc < 0) {
		fprintf(stderr, "Error claiming interface\n");
		exit(1);
	}

	benchmark_in();

	while (1) {
		libusb_handle_events(NULL);
	}

}