int
XNextEvent (
register Display *dpy,
register XEvent *event)
{
register _XQEvent *qelt;
LockDisplay(dpy);
/* Delete unclaimed cookies */
_XFreeEventCookies(dpy);
if (dpy->head == NULL)
_XReadEvents(dpy);
qelt = dpy->head;
*event = qelt->event;
_XDeq(dpy, NULL, qelt);
_XStoreEventCookie(dpy, event);
UnlockDisplay(dpy);
return 0;
}
int
XPeekIfEvent (
register Display *dpy,
register XEvent *event,
Bool (*predicate)(
Display* /* display */,
XEvent* /* event */,
char* /* arg */
),
char *arg)
{
register _XQEvent *prev, *qelt;
unsigned long qe_serial = 0;
LockDisplay(dpy);
prev = NULL;
while (1) {
for (qelt = prev ? prev->next : dpy->head;
qelt;
prev = qelt, qelt = qelt->next) {
if(qelt->qserial_num > qe_serial
&& (*predicate)(dpy, &qelt->event, arg)) {
XEvent copy;
*event = qelt->event;
if (_XCopyEventCookie(dpy, &event->xcookie, ©.xcookie)) {
_XStoreEventCookie(dpy, ©);
*event = copy;
}
UnlockDisplay(dpy);
return 0;
}
}
if (prev)
qe_serial = prev->qserial_num;
_XReadEvents(dpy);
if (prev && prev->qserial_num != qe_serial)
/* another thread has snatched this event */
prev = NULL;
}
}
int
XWindowEvent (
register Display *dpy,
Window w, /* Selected window. */
long mask, /* Selected event mask. */
register XEvent *event) /* XEvent to be filled in. */
{
register _XQEvent *prev, *qelt;
unsigned long qe_serial = 0;
LockDisplay(dpy);
/* Delete unclaimed cookies */
_XFreeEventCookies(dpy);
prev = NULL;
while (1) {
for (qelt = prev ? prev->next : dpy->head;
qelt;
prev = qelt, qelt = qelt->next) {
if ((qelt->event.xany.window == w) &&
(qelt->event.type < GenericEvent) &&
(_Xevent_to_mask[qelt->event.type] & mask) &&
((qelt->event.type != MotionNotify) ||
(mask & AllPointers) ||
(mask & AllButtons & qelt->event.xmotion.state))) {
*event = qelt->event;
_XDeq(dpy, prev, qelt);
UnlockDisplay(dpy);
return 0;
}
}
if (prev)
qe_serial = prev->qserial_num;
_XReadEvents(dpy);
if (prev && prev->qserial_num != qe_serial)
/* another thread has snatched this event */
prev = NULL;
}
}
