scx/scheme/xlib/event.scm

66 lines
2.0 KiB
Scheme

;; Thread-safe event reading *****************************************
;; wait-event blocks the current thread until an event is available,
;; and then it returns this new event.
(define (wait-event dpy)
(if (> (events-queued dpy (queued-mode after-flush)) 0)
(next-event dpy)
(begin
;;(sleep-display dpy)
(block-on-message-inport dpy)
(wait-event dpy))))
;(define (block-on-message-inport dpy) ; needs ports, locks
; (let ((port (display-message-inport dpy)))
; (disable-interrupts!)
; (if (not (char-ready? port))
; (begin
; (obtain-lock (port-lock port))
; (add-pending-channel (port->channel port))
; (wait-for-channel (port->channel port)) ;; enables interrupts
; (release-lock (port-lock port)))
; (enable-interrupts!))))
;;; Only here until scsh provides us with select
;(import-lambda-definition add-pending-channel (channel)
; "scx_add_pending_channel")
;; How to find out if there are events available *********************
(define-enumerated-type queued-mode :queued-mode
queued-mode? queued-modes queued-mode-name queued-mode-index
(already after-reading after-flush))
(define-exported-binding "scx-queued-mode" :queued-mode)
(import-lambda-definition events-queued (display mode)
"scx_Events_Queued")
(define (event-ready? display)
(or (> (events-queued display (queued-mode already)) 0)
(char-ready? (display-message-inport display))))
;; events-pending is identical to events-queued with after-flush
;; mode.
(import-lambda-definition events-pending (display)
"scx_Events_Pending")
;; Other event reading ***********************************************
(import-lambda-definition next-event (display)
"scx_Next_Event")
(import-lambda-definition peek-event (display)
"scx_Peek_Event")
;; returns a list of (time . (x . y)) elements
(import-lambda-definition get-motion-events (display window from to)
"scx_Get_Motion_Events")
;; Sending events ****************************************************
(import-lambda-definition send-event (display window propagate mask event)
"scx_Send_Event")