tkevent.c

linux系统下的音频通信

    }

    if (winPtr->mainPtr != NULL) {

        /*
         * Protect interpreter for this window from possible deletion
         * while we are dealing with the event for this window. Thus,
         * widget writers do not have to worry about protecting the
         * interpreter in their own code.
         */
        
        interp = winPtr->mainPtr->interp;
        Tcl_Preserve((ClientData) interp);
        
	/*
	 * Call focus-related code to look at FocusIn, FocusOut, Enter,
	 * and Leave events;  depending on its return value, ignore the
	 * event.
	 */
    
	if ((mask & (FocusChangeMask|EnterWindowMask|LeaveWindowMask))
		&& !TkFocusFilterEvent(winPtr, eventPtr)) {
            Tcl_Release((ClientData) interp);
	    return;
	}
    
	/*
	 * Redirect KeyPress and KeyRelease events to the focus window,
	 * or ignore them entirely if there is no focus window.
	 */
    
	if (mask & (KeyPressMask|KeyReleaseMask)) {
	    winPtr->dispPtr->lastEventTime = eventPtr->xkey.time;
	    winPtr = TkFocusKeyEvent(winPtr, eventPtr);
	    if (winPtr == NULL) {
                Tcl_Release((ClientData) interp);
		return;
	    }
	}
    
	/*
	 * Call a grab-related procedure to do special processing on
	 * pointer events.
	 */
    
	if (mask & (ButtonPressMask|ButtonReleaseMask|PointerMotionMask
		|EnterWindowMask|LeaveWindowMask)) {
	    if (mask & (ButtonPressMask|ButtonReleaseMask)) {
		winPtr->dispPtr->lastEventTime = eventPtr->xbutton.time;
	    } else if (mask & PointerMotionMask) {
		winPtr->dispPtr->lastEventTime = eventPtr->xmotion.time;
	    } else {
		winPtr->dispPtr->lastEventTime = eventPtr->xcrossing.time;
	    }
	    if (TkPointerEvent(eventPtr, winPtr) == 0) {
                goto done;
	    }
	}
    }

#ifdef TK_USE_INPUT_METHODS
    /*
     * Pass the event to the input method(s), if there are any, and
     * discard the event if the input method(s) insist.  Create the
     * input context for the window if it hasn't already been done
     * (XFilterEvent needs this context).
     */

    if (!(winPtr->flags & TK_CHECKED_IC)) {
	if (winPtr->dispPtr->inputMethod != NULL) {
	    winPtr->inputContext = XCreateIC(
		    winPtr->dispPtr->inputMethod, XNInputStyle,
		    XIMPreeditNothing|XIMStatusNothing,
		    XNClientWindow, winPtr->window,
		    XNFocusWindow, winPtr->window, NULL);
	}
	winPtr->flags |= TK_CHECKED_IC;
    }
    if (XFilterEvent(eventPtr, None)) {
        goto done;
    }
#endif /* TK_USE_INPUT_METHODS */

    /*
     * For events where it hasn't already been done, update the current
     * time in the display.
     */

    if (eventPtr->type == PropertyNotify) {
	winPtr->dispPtr->lastEventTime = eventPtr->xproperty.time;
    }

    /*
     * There's a potential interaction here with Tk_DeleteEventHandler.
     * Read the documentation for pendingPtr.
     */

    ip.eventPtr = eventPtr;
    ip.winPtr = winPtr;
    ip.nextHandler = NULL;
    ip.nextPtr = pendingPtr;
    pendingPtr = &ip;
    if (mask == 0) {
	if ((eventPtr->type == SelectionClear)
		|| (eventPtr->type == SelectionRequest)
		|| (eventPtr->type == SelectionNotify)) {
	    TkSelEventProc((Tk_Window) winPtr, eventPtr);
	} else if ((eventPtr->type == ClientMessage)
		&& (eventPtr->xclient.message_type ==
		    Tk_InternAtom((Tk_Window) winPtr, "WM_PROTOCOLS"))) {
	    TkWmProtocolEventProc(winPtr, eventPtr);
	}
    } else {
	for (handlerPtr = winPtr->handlerList; handlerPtr != NULL; ) {
	    if ((handlerPtr->mask & mask) != 0) {
		ip.nextHandler = handlerPtr->nextPtr;
		(*(handlerPtr->proc))(handlerPtr->clientData, eventPtr);
		handlerPtr = ip.nextHandler;
	    } else {
		handlerPtr = handlerPtr->nextPtr;
	    }
	}

	/*
	 * Pass the event to the "bind" command mechanism.  But, don't
	 * do this for SubstructureNotify events.  The "bind" command
	 * doesn't support them anyway, and it's easier to filter out
	 * these events here than in the lower-level procedures.
	 */

	if ((ip.winPtr != None) && (mask != SubstructureNotifyMask)) {
	    TkBindEventProc(winPtr, eventPtr);
	}
    }
    pendingPtr = ip.nextPtr;
done:

    /*
     * Release the interpreter for this window so that it can be potentially
     * deleted if requested.
     */
    
    if (interp != (Tcl_Interp *) NULL) {
        Tcl_Release((ClientData) interp);
    }
}

/*
 *--------------------------------------------------------------
 *
 * TkEventDeadWindow --
 *
 *	This procedure is invoked when it is determined that
 *	a window is dead.  It cleans up event-related information
 *	about the window.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Various things get cleaned up and recycled.
 *
 *--------------------------------------------------------------
 */

void
TkEventDeadWindow(winPtr)
    TkWindow *winPtr;		/* Information about the window
				 * that is being deleted. */
{
    register TkEventHandler *handlerPtr;
    register InProgress *ipPtr;

    /*
     * While deleting all the handlers, be careful to check for
     * Tk_HandleEvent being about to process one of the deleted
     * handlers.  If it is, tell it to quit (all of the handlers
     * are being deleted).
     */

    while (winPtr->handlerList != NULL) {
	handlerPtr = winPtr->handlerList;
	winPtr->handlerList = handlerPtr->nextPtr;
	for (ipPtr = pendingPtr; ipPtr != NULL; ipPtr = ipPtr->nextPtr) {
	    if (ipPtr->nextHandler == handlerPtr) {
		ipPtr->nextHandler = NULL;
	    }
	    if (ipPtr->winPtr == winPtr) {
		ipPtr->winPtr = None;
	    }
	}
	ckfree((char *) handlerPtr);
    }
}

/*
 *----------------------------------------------------------------------
 *
 * TkCurrentTime --
 *
 *	Try to deduce the current time.  "Current time" means the time
 *	of the event that led to the current code being executed, which
 *	means the time in the most recently-nested invocation of
 *	Tk_HandleEvent.
 *
 * Results:
 *	The return value is the time from the current event, or
 *	CurrentTime if there is no current event or if the current
 *	event contains no time.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

Time
TkCurrentTime(dispPtr)
    TkDisplay *dispPtr;		/* Display for which the time is desired. */
{
    register XEvent *eventPtr;

    if (pendingPtr == NULL) {
	return dispPtr->lastEventTime;
    }
    eventPtr = pendingPtr->eventPtr;
    switch (eventPtr->type) {
	case ButtonPress:
	case ButtonRelease:
	    return eventPtr->xbutton.time;
	case KeyPress:
	case KeyRelease:
	    return eventPtr->xkey.time;
	case MotionNotify:
	    return eventPtr->xmotion.time;
	case EnterNotify:
	case LeaveNotify:
	    return eventPtr->xcrossing.time;
	case PropertyNotify:
	    return eventPtr->xproperty.time;
    }
    return dispPtr->lastEventTime;
}

/*
 *----------------------------------------------------------------------
 *
 * Tk_RestrictEvents --
 *
 *	This procedure is used to globally restrict the set of events
 *	that will be dispatched.  The restriction is done by filtering
 *	all incoming X events through a procedure that determines
 *	whether they are to be processed immediately, deferred, or
 *	discarded.
 *
 * Results:
 *	The return value is the previous restriction procedure in effect,
 *	if there was one, or NULL if there wasn't.
 *
 * Side effects:
 *	From now on, proc will be called to determine whether to process,
 *	defer or discard each incoming X event.
 *
 *----------------------------------------------------------------------
 */

Tk_RestrictProc *
Tk_RestrictEvents(proc, arg, prevArgPtr)
    Tk_RestrictProc *proc;	/* Procedure to call for each incoming
				 * event. */
    ClientData arg;		/* Arbitrary argument to pass to proc. */
    ClientData *prevArgPtr;	/* Place to store information about previous
				 * argument. */
{
    Tk_RestrictProc *prev;

    prev = restrictProc;
    *prevArgPtr = restrictArg;
    restrictProc = proc;
    restrictArg = arg;
    return prev;
}

/*
 *----------------------------------------------------------------------
 *
 * Tk_QueueWindowEvent --
 *
 *	Given an X-style window event, this procedure adds it to the
 *	Tcl event queue at the given position.  This procedure also
 *	performs mouse motion event collapsing if possible.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Adds stuff to the event queue, which will eventually be
 *	processed.
 *
 *----------------------------------------------------------------------
 */

void
Tk_QueueWindowEvent(eventPtr, position)
    XEvent *eventPtr;			/* Event to add to queue.  This
					 * procedures copies it before adding
					 * it to the queue. */
    Tcl_QueuePosition position;		/* Where to put it on the queue:
					 * TCL_QUEUE_TAIL, TCL_QUEUE_HEAD,
					 * or TCL_QUEUE_MARK. */
{
    TkWindowEvent *wevPtr;
    TkDisplay *dispPtr;

    /*
     * Find our display structure for the event's display.
     */

    for (dispPtr = tkDisplayList; ; dispPtr = dispPtr->nextPtr) {
	if (dispPtr == NULL) {
	    return;
	}
	if (dispPtr->display == eventPtr->xany.display) {
	    break;
	}
    }

    if ((dispPtr->delayedMotionPtr != NULL) && (position == TCL_QUEUE_TAIL)) {
	if ((eventPtr->type == MotionNotify) && (eventPtr->xmotion.window
		== dispPtr->delayedMotionPtr->event.xmotion.window)) {
	    /*
	     * The new event is a motion event in the same window as the
	     * saved motion event.  Just replace the saved event with the
	     * new one.
	     */

	    dispPtr->delayedMotionPtr->event = *eventPtr;
	    return;
	} else if ((eventPtr->type != GraphicsExpose)
		&& (eventPtr->type != NoExpose)
		&& (eventPtr->type != Expose)) {
	    /*
	     * The new event may conflict with the saved motion event.  Queue
	     * the saved motion event now so that it will be processed before
	     * the new event.
	     */

	    Tcl_QueueEvent(&dispPtr->delayedMotionPtr->header, position);
	    dispPtr->delayedMotionPtr = NULL;
	    Tcl_CancelIdleCall(DelayedMotionProc, (ClientData) dispPtr);
	}
    }

    wevPtr = (TkWindowEvent *) ckalloc(sizeof(TkWindowEvent));
    wevPtr->header.proc = WindowEventProc;
    wevPtr->event = *eventPtr;
    if ((eventPtr->type == MotionNotify) && (position == TCL_QUEUE_TAIL)) {
	/*
	 * The new event is a motion event so don't queue it immediately;
	 * save it around in case another motion event arrives that it can
	 * be collapsed with.
	 */

	if (dispPtr->delayedMotionPtr != NULL) {
	    panic("Tk_QueueWindowEvent found unexpected delayed motion event");
	}
	dispPtr->delayedMotionPtr = wevPtr;
	Tcl_DoWhenIdle(DelayedMotionProc, (ClientData) dispPtr);
    } else {
	Tcl_QueueEvent(&wevPtr->header, position);
    }
}

/*
 *---------------------------------------------------------------------------
 *
 * TkQueueEventForAllChildren --
 *
 *	Given an XEvent, recursively queue the event for this window and
 *	all non-toplevel children of the given window.  
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Events queued.
 *
 *---------------------------------------------------------------------------
 */

void
TkQueueEventForAllChildren(winPtr, eventPtr)
    TkWindow *winPtr;	    /* Window to which event is sent. */
    XEvent *eventPtr;	    /* The event to be sent. */
{
    TkWindow *childPtr;

    eventPtr->xany.window = winPtr->window;
    Tk_QueueWindowEvent(eventPtr, TCL_QUEUE_TAIL);
    
    childPtr = winPtr->childList;
    while (childPtr != NULL) {
	if (!Tk_IsTopLevel(childPtr)) {
	    TkQueueEventForAllChildren(childPtr, eventPtr);
	}
	childPtr = childPtr->nextPtr;
    }
}

/*
 *----------------------------------------------------------------------
 *
 * WindowEventProc --
 *
 *	This procedure is called by Tcl_DoOneEvent when a window event
 *	reaches the front of the event queue.  This procedure is responsible
 *	for actually handling the event.
 *
 * Results:
 *	Returns 1 if the event was handled, meaning it should be removed
 *	from the queue.  Returns 0 if the event was not handled, meaning
 *	it should stay on the queue.  The event isn't handled if the
 *	TCL_WINDOW_EVENTS bit isn't set in flags, if a restrict proc
 *	prevents the event from being handled.
 *
 * Side effects:
 *	Whatever the event handlers for the event do.
 *
 *----------------------------------------------------------------------
 */

static int
WindowEventProc(evPtr, flags)
    Tcl_Event *evPtr;		/* Event to service. */
    int flags;			/* Flags that indicate what events to
				 * handle, such as TCL_WINDOW_EVENTS. */
{
    TkWindowEvent *wevPtr = (TkWindowEvent *) evPtr;
    Tk_RestrictAction result;

    if (!(flags & TCL_WINDOW_EVENTS)) {
	return 0;
    }
    if (restrictProc != NULL) {
	result = (*restrictProc)(restrictArg, &wevPtr->event);
	if (result != TK_PROCESS_EVENT) {
	    if (result == TK_DEFER_EVENT) {
		return 0;
	    } else {
		/*
		 * TK_DELETE_EVENT: return and say we processed the event,
		 * even though we didn't do anything at all.
		 */
		return 1;
	    }
	}
    }
    Tk_HandleEvent(&wevPtr->event);
    return 1;
}

/*
 *----------------------------------------------------------------------
 *
 * DelayedMotionProc --
 *
 *	This procedure is invoked as an idle handler when a mouse motion
 *	event has been delayed.  It queues the delayed event so that it
 *	will finally be serviced.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	The delayed mouse motion event gets added to the Tcl event
 *	queue for servicing.
 *
 *----------------------------------------------------------------------
 */

static void
DelayedMotionProc(clientData)
    ClientData clientData;	/* Pointer to display containing a delayed
				 * motion event to be serviced. */
{
    TkDisplay *dispPtr = (TkDisplay *) clientData;

    if (dispPtr->delayedMotionPtr == NULL) {
	panic("DelayedMotionProc found no delayed mouse motion event");
    }
    Tcl_QueueEvent(&dispPtr->delayedMotionPtr->header, TCL_QUEUE_TAIL);
    dispPtr->delayedMotionPtr = NULL;
}

/*
 *--------------------------------------------------------------
 *
 * Tk_MainLoop --
 *
 *	Call Tcl_DoOneEvent over and over again in an infinite
 *	loop as long as there exist any main windows.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Arbitrary;  depends on handlers for events.
 *
 *--------------------------------------------------------------
 */

void
Tk_MainLoop()
{
    while (Tk_GetNumMainWindows() > 0) {
	Tcl_DoOneEvent(0);
    }
}