GObject LD_PRELOAD override

gobject-override.c

/*
gcc -shared -fPIC -o liboverride.so gobject-override.c -ldl $(pkg-config --cflags --libs glib-2.0 gtk+-3.0)
LD_PRELOAD=./liboverride.so any-binary!
*/

#define _GNU_SOURCE 1
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
#include <dlfcn.h>
#include <gtk/gtk.h>

void g_object_unref(gpointer object)
{
  void (*orig_unref)(gpointer) = dlsym(RTLD_NEXT, "g_object_unref");

  if (GTK_IS_WIDGET (object))
    printf("Calling Unref on %p, ref_count %d\n",object,G_OBJECT(object)->ref_count);

  orig_unref(object);
}