+void
+_dbus_trace_ref (const char *obj_name,
+ void *obj,
+ int old_refcount,
+ int new_refcount,
+ const char *why,
+ const char *env_var,
+ int *enabled)
+{
+ _dbus_assert (obj_name != NULL);
+ _dbus_assert (obj != NULL);
+ _dbus_assert (old_refcount >= -1);
+ _dbus_assert (new_refcount >= -1);
+
+ if (old_refcount == -1)
+ {
+ _dbus_assert (new_refcount == -1);
+ }
+ else
+ {
+ _dbus_assert (new_refcount >= 0);
+ _dbus_assert (old_refcount >= 0);
+ _dbus_assert (old_refcount > 0 || new_refcount > 0);
+ }
+
+ _dbus_assert (why != NULL);
+ _dbus_assert (env_var != NULL);
+ _dbus_assert (enabled != NULL);
+
+ if (*enabled < 0)
+ {
+ const char *s = _dbus_getenv (env_var);
+
+ *enabled = FALSE;
+
+ if (s && *s)
+ {
+ if (*s == '0')
+ *enabled = FALSE;
+ else if (*s == '1')
+ *enabled = TRUE;
+ else
+ _dbus_warn ("%s should be 0 or 1 if set, not '%s'", env_var, s);
+ }
+ }
+
+ if (*enabled)
+ {
+ if (old_refcount == -1)
+ {
+ VALGRIND_PRINTF_BACKTRACE ("%s %p ref stolen (%s)",
+ obj_name, obj, why);
+ _dbus_verbose ("%s %p ref stolen (%s)",
+ obj_name, obj, why);
+ }
+ else
+ {
+ VALGRIND_PRINTF_BACKTRACE ("%s %p %d -> %d refs (%s)",
+ obj_name, obj,
+ old_refcount, new_refcount, why);
+ _dbus_verbose ("%s %p %d -> %d refs (%s)",
+ obj_name, obj, old_refcount, new_refcount, why);
+ }
+ }
+}
+