x11-device-monitor.c

#if 0
src = $(MAKEFILE_LIST)
app = $(basename $(src))

$(app): LDLIBS = -lX11 -lXi
$(app): $(src)

define source
#endif

/* http://who-t.blogspot.com/2009/05/xi2-recipes-part-1.html */

#define _GNU_SOURCE
#include <X11/Xlib.h>
#include <X11/extensions/XInput2.h>
#include <err.h>
#include <stdlib.h>

int main(void) {
	Display *d;
	Window rw;
	int xinput_op, foo;
	unsigned char mask[2] = {0};
	XIEventMask ximask;
	XEvent ev;
	XIHierarchyEvent *hev;

	d = XOpenDisplay(NULL);
	if (!d)
		errx(1, "cannot open display");
	if (!XQueryExtension(d, "XInputExtension", &xinput_op, &foo, &foo))
		errx(1, "no XInput extension on display");
	rw = RootWindow(d, DefaultScreen(d));
	XISetMask(mask, XI_HierarchyChanged);
	ximask.mask = mask;
	ximask.mask_len = sizeof(mask);
	ximask.deviceid = XIAllDevices;
	XISelectEvents(d, rw, &ximask, 1);
	XFlush(d);
	for (;;) {
		XNextEvent(d, &ev);
		if (ev.type != GenericEvent)
			continue;
		/* XInput2 always uses extended events */
		/* http://who-t.blogspot.com/2009/07/xi2-and-xlib-cookies.html */
		if (ev.xcookie.extension != xinput_op)
			continue;
		if (ev.xcookie.evtype != XI_HierarchyChanged)
			continue;
		if (!XGetEventData(d, &ev.xcookie))
			continue;
		hev = ev.xcookie.data;
		if (!(hev->flags & XIDeviceEnabled))
			continue;
		warnx("device enabled");
		system("xmodmap ~/.Xmodmap");
		XFreeEventData(d, &ev.xcookie);
	}
}

#if 0
endef
#endif