/* shflip.c */
#include <stdio.h>
#include <string.h>
#include <sys/types.h>
#include <linux/types.h>
#include <sys/ioctl.h>
#include <linux/videodev2.h>
#include <fcntl.h>
#include <errno.h>


main(int argc, char *argv[])
{
    int fd = open("/dev/video0", O_RDWR);
    int ret;
    struct v4l2_queryctrl queryctrl;
    struct v4l2_control ctrl;

    memset(&queryctrl, 0, sizeof(queryctrl));
    for (queryctrl.id = V4L2_CID_BASE;
         queryctrl.id < V4L2_CID_LASTP1;
         queryctrl.id++) {
        if (0 == ioctl (fd, VIDIOC_QUERYCTRL, &queryctrl)) {
            if (queryctrl.flags & V4L2_CTRL_FLAG_DISABLED)
                continue;

            printf ("Control %s\n", queryctrl.name);

        } else {
            if (errno == EINVAL)
                continue;

            perror ("VIDIOC_QUERYCTRL");
            return (1);
        }
    }

    memset(&ctrl, 0, sizeof(ctrl));
    ctrl.id = V4L2_CID_HFLIP;
    ret = ioctl(fd, VIDIOC_G_CTRL, &ctrl);
    printf("Get H flip, ret %d value %d\n", ret, ctrl.value);
    if (argc > 1) {
        ctrl.value = atoi(argv[1]);
        ret = ioctl(fd, VIDIOC_S_CTRL, &ctrl);
        printf("Set to %d, ret %d\n", ctrl.value, ret);
    }
}