/*
 * cc -o test test.c -lX11 $(pkg-config --cflags --libs  xorg-libinput xi)
 */

#include <stdio.h>
#include <X11/Xlib.h>
#include <X11/Xatom.h>
#include <X11/extensions/XInput.h>
#include <libinput-properties.h>

static int
xfce_pointers_is_libinput (Display *xdisplay,
                           XDevice *device)
{
    Atom     prop, type;
    unsigned long   n_items, bytes_after;
    int     rc, format;
    unsigned char  *data;

    prop = XInternAtom (xdisplay, LIBINPUT_PROP_LEFT_HANDED, False);
    rc = XGetDeviceProperty (xdisplay, device, prop, 0, 1, False,
                             XA_INTEGER, &type, &format, &n_items,
                             &bytes_after, &data);
    if (rc == Success)
    {
        /* Replace the prop with the same value */
        XChangeDeviceProperty (xdisplay, device, prop, type, format,
                               PropModeReplace, data, n_items);
        XFree (data);
        return (n_items > 0);
    }

    return 0;
}

int main (void)
{
    Display     *xdisplay;
    XDeviceInfo *device_list, *device_info;
    XDevice     *device;
    int          n, ndevices;

    xdisplay = XOpenDisplay(NULL);
    if (!xdisplay) {
        fprintf (stderr, "Cannot open display\n");
        return -1;
    }

    device_list = XListInputDevices (xdisplay, &ndevices);
    for (n = 0; n < ndevices; n++)
    {
        device_info = &device_list[n];
        if (device_info->use != IsXExtensionPointer || device_info->name == NULL)
            continue;

        /* open the device */
        device = XOpenDevice (xdisplay, device_info->id);
        if (device == NULL)
        {
            fprintf (stderr, "Unable to open device %s\n", device_info->name);
            continue;
        }
        fprintf (stdout, "Device %d (%s) is%s managed by libinput\n",
                   device_info->id, device_info->name,
                   xfce_pointers_is_libinput (xdisplay, device) ? "" : " not");

        XCloseDevice (xdisplay, device);
    }
    XFreeDeviceList (device_list);
    XCloseDisplay(xdisplay);
}