Added libXt library

1 files changed, 851 insertions, 0 deletions

diff --git a/libXt/src/Keyboard.c b/libXt/src/Keyboard.c
new file mode 100644
index 000000000..6c4a62a18
--- /dev/null
+++ b/libXt/src/Keyboard.c
@@ -0,0 +1,851 @@
+/* $Xorg: Keyboard.c,v 1.5 2001/02/09 02:03:55 xorgcvs Exp $ */
+
+/********************************************************
+
+Copyright 1988 by Hewlett-Packard Company
+Copyright 1987, 1988, 1989 by Digital Equipment Corporation, Maynard, Massachusetts
+Copyright 1993 by Sun Microsystems, Inc. Mountain View, CA.
+
+Permission to use, copy, modify, and distribute this software
+and its documentation for any purpose and without fee is hereby
+granted, provided that the above copyright notice appear in all
+copies and that both that copyright notice and this permission
+notice appear in supporting documentation, and that the names of
+Hewlett-Packard, Digital, or Sun not be used in advertising or
+publicity pertaining to distribution of the software without specific,
+written prior permission.
+
+DIGITAL DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING
+ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL
+DIGITAL BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR
+ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
+WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
+ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
+SOFTWARE.
+
+SUN DISCLAIMS ALL WARRANTIES WITH REGARD TO  THIS  SOFTWARE,
+INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FIT-
+NESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL SUN BE  LI-
+ABLE  FOR  ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR
+ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,  DATA  OR
+PROFITS,  WHETHER  IN  AN  ACTION OF CONTRACT, NEGLIGENCE OR
+OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION  WITH
+THE USE OR PERFORMANCE OF THIS SOFTWARE.
+
+********************************************************/
+
+/*
+
+Copyright 1987, 1988, 1994, 1998  The Open Group
+
+Permission to use, copy, modify, distribute, and sell this software and its
+documentation for any purpose is hereby granted without fee, provided that
+the above copyright notice appear in all copies and that both that
+copyright notice and this permission notice appear in supporting
+documentation.
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
+OPEN GROUP BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+Except as contained in this notice, the name of The Open Group shall not be
+used in advertising or otherwise to promote the sale, use or other dealings
+in this Software without prior written authorization from The Open Group.
+
+*/
+/* $XFree86: xc/lib/Xt/Keyboard.c,v 3.3 2001/08/22 22:52:19 dawes Exp $ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+#include "IntrinsicI.h"
+
+#include "PassivGraI.h"
+#include "EventI.h"
+
+#define _GetWindowedAncestor(w) (XtIsWidget(w) ? w : _XtWindowedAncestor(w))
+
+/* InActiveSubtree cache of the current focus source and its ancestors */
+static Widget	*pathTrace = NULL;
+static int	pathTraceDepth = 0;
+static int	pathTraceMax = 0;
+
+/* FindKeyDestination cache of focus destination and ancestors up to source */
+static Widget	*pseudoTrace = NULL;
+static int	pseudoTraceDepth = 0;
+static int	pseudoTraceMax = 0;
+
+void _XtClearAncestorCache(Widget widget)
+{
+    /* the caller must lock the process lock */
+    if (pathTraceDepth && pathTrace[0] == widget)
+	pathTraceDepth = 0;
+}
+
+static XtServerGrabPtr CheckServerGrabs(
+    XEvent	*event,
+    Widget	*trace,
+    Cardinal	traceDepth)
+{
+    XtServerGrabPtr 	grab;
+    Cardinal		i;
+
+    for (i = traceDepth;  i > 0; i--)
+      {
+	 if ((grab = _XtCheckServerGrabsOnWidget(event, trace[i-1], KEYBOARD)))
+	   return (grab);
+     }
+    return (XtServerGrabPtr)0;
+}
+
+static Boolean IsParent(Widget a, Widget b)
+{
+    for (b = XtParent(b); b; b = XtParent(b)) {
+      if (b == a) return TRUE;
+      if (XtIsShell(b)) return FALSE;
+    }
+    return FALSE;
+}
+
+#define RelRtn(lca, type) {*relTypeRtn = type; return lca;}
+
+static Widget CommonAncestor(
+    register Widget a,
+    register Widget b,
+    XtGeneology  * relTypeRtn)
+{
+    if (a == b)
+      {
+	  RelRtn(a, XtMySelf)
+	}
+    else if (IsParent(a, b))
+      {
+	  RelRtn(a, XtMyAncestor)
+	}
+    else if (IsParent(b, a))
+      {
+	  RelRtn(b, XtMyDescendant)
+	}
+    else
+      for (b = XtParent(b);
+	   b && !XtIsShell(b);
+	   b = XtParent(b))
+	if (IsParent(b, a))
+	  {
+	      RelRtn(b, XtMyCousin)
+	    }
+    RelRtn(NULL, XtUnrelated)
+}
+#undef RelRtn
+
+
+
+
+
+static Widget _FindFocusWidget(
+    Widget 	widget,
+    Widget	*trace,
+    int		traceDepth,
+    Boolean	activeCheck,
+    Boolean	*isTarget)
+{
+    int src;
+    Widget dst;
+    XtPerWidgetInput	pwi = NULL;
+
+    /* For each ancestor, starting at the top, see if it's forwarded */
+
+
+    /* first check the trace list till done or we go to branch */
+    for (src = traceDepth-1, dst = widget; src > 0;)
+      {
+	  if ((pwi = _XtGetPerWidgetInput(trace[src], FALSE)))
+	    {
+		if (pwi->focusKid)
+		  {
+		      dst = pwi->focusKid;
+		      for (src--; src > 0 && trace[src] != dst; src--) {}
+		  }
+		else dst = trace[--src];
+	    }
+	  else dst = trace[--src];
+      }
+
+    if (isTarget) {
+	if (pwi && pwi->focusKid == widget)
+	    *isTarget = TRUE;
+	else
+	    *isTarget = FALSE;
+    }
+
+    if (!activeCheck)
+      while (XtIsWidget(dst)
+	     && (pwi = _XtGetPerWidgetInput(dst, FALSE))
+	     && pwi->focusKid)
+	dst = pwi->focusKid;
+
+    return dst;
+}
+
+
+static Widget FindFocusWidget(
+    Widget		widget,
+    XtPerDisplayInput 	pdi)
+{
+    if (pdi->focusWidget)
+      return  pdi->focusWidget;
+    else
+      return _FindFocusWidget(widget, pdi->trace, pdi->traceDepth, FALSE, NULL);
+}
+
+Widget XtGetKeyboardFocusWidget(Widget widget)
+{
+    XtPerDisplayInput pdi;
+    Widget retval;
+    WIDGET_TO_APPCON(widget);
+
+    LOCK_APP(app);
+    pdi = _XtGetPerDisplayInput(XtDisplay(widget));
+    retval = FindFocusWidget(widget, pdi);
+    UNLOCK_APP(app);
+    return retval;
+}
+
+static Boolean IsOutside(
+    XKeyEvent	*e,
+    Widget	w)
+{
+    Position left, right, top, bottom;
+
+    /*
+     * if the pointer is outside the shell or inside
+     * the window try to see if it would recieve the
+     * focus
+     */
+    XtTranslateCoords(w, 0, 0, &left, &top);
+    /* We need to take borders into consideration */
+    left = left - w->core.border_width;
+    top =  top - w->core.border_width;
+    right = left +  w->core.width + w->core.border_width;
+    bottom = top +  w->core.height + w->core.border_width;
+
+    if (
+	(e->x_root < left) || (e->y_root < top) ||
+        (e->x_root > right) || (e->y_root > bottom))
+      return TRUE;
+    else
+      return FALSE;
+}
+
+static Widget 	FindKeyDestination(
+    Widget		widget,
+    XKeyEvent		*event,
+    XtServerGrabPtr	prevGrab,
+    XtServerGrabType 	prevGrabType,
+    XtServerGrabPtr	devGrab,
+    XtServerGrabType	devGrabType,
+    XtPerDisplayInput	pdi)
+{
+
+    Widget		dspWidget;
+    Widget		focusWidget;
+
+    LOCK_PROCESS;
+    dspWidget =
+      focusWidget =
+	pdi->focusWidget =
+	  _GetWindowedAncestor(FindFocusWidget(widget, pdi));
+
+
+    /*
+     * If a grab is active from a previous activation then dispatch
+     * based on owner_events ala protocol but with focus being
+     * determined by XtSetKeyboardFocus.
+     */
+    if 	(IsAnyGrab(prevGrabType))
+      {
+	  if (prevGrab->ownerEvents)
+	    dspWidget = focusWidget;
+	  else
+	    dspWidget = prevGrab->widget;
+      }
+    else
+      {
+	  /*
+           * If the focus widget is the event widget or a descendant
+	   * then we can avoid the rest of this. Else ugh...
+	   */
+	  if (focusWidget != widget)
+	    {
+		XtGeneology 	ewRelFw; /* relationship of event widget to
+					    focusWidget */
+		Widget		lca;
+
+		lca = CommonAncestor(widget, focusWidget, &ewRelFw);
+
+		/*
+		 * if the event widget is an ancestor of focus due to the pointer
+		 * and/or the grab being in an ancestor and it's a passive grab
+		 * send to grab widget.
+		 * we are also dispatching to widget if ownerEvents and the event
+		 * is outside the client
+		 */
+		if ((ewRelFw == XtMyAncestor) &&
+		    (devGrabType == XtPassiveServerGrab))
+		     {
+			 if (IsOutside(event, widget) ||
+			     event->type ==KeyPress
+			     )
+			   dspWidget = devGrab->widget;
+		     }
+		else
+		  {
+		      /*
+		       * if the grab widget is not an ancestor of the focus
+		       * release the grab in order to avoid locking. There
+		       * is a possible case  in that ownerEvents true will fall
+		       * through and if synch is set and the event widget
+		       * could turn it off we'll lock. check for it ? why not
+		       */
+		      if ((ewRelFw != XtMyAncestor)
+			  && (devGrabType == XtPassiveServerGrab)
+			  && (!IsAnyGrab(prevGrabType))
+			  )
+			{
+			    XtUngrabKeyboard(devGrab->widget,
+					     event->time);
+			    devGrabType = XtNoServerGrab;
+			}
+		      /*
+		       * if there isn't a grab with then check
+		       * for a logical grab that would have been activated
+		       * if the server was using Xt focus instead of server
+		       * focus
+		       */
+		      if (
+			  (event->type != KeyPress) ||
+			  (event->keycode == 0) /* Xlib XIM composed input */
+			  )
+			dspWidget = focusWidget;
+		      else
+			{
+			    XtServerGrabPtr	grab;
+
+			    if (!pseudoTraceDepth ||
+				!(focusWidget == pseudoTrace[0]) ||
+				!(lca == pseudoTrace[pseudoTraceDepth]))
+			      {
+				  /*
+				   * fill ancestor list from lca
+				   * (non-inclusive)to focusWidget by
+				   * passing in lca as breakWidget
+				   */
+				  _XtFillAncestorList(&pseudoTrace,
+						   &pseudoTraceMax,
+						   &pseudoTraceDepth,
+						   focusWidget,
+						   lca);
+				  /* ignore lca */
+				  pseudoTraceDepth--;
+			      }
+			    if ((grab = CheckServerGrabs((XEvent*)event,
+							pseudoTrace,
+							pseudoTraceDepth)))
+			      {
+				  XtDevice device = &pdi->keyboard;
+
+				  device->grabType = XtPseudoPassiveServerGrab;
+				  pdi->activatingKey = event->keycode;
+				  device->grab = *grab;
+
+				  if (grab
+				      )
+				    dspWidget = grab->widget;
+				  else
+				    dspWidget = focusWidget;
+			      }
+			}
+		  }
+	    }
+      }
+    UNLOCK_PROCESS;
+    return dspWidget;
+}
+
+Widget _XtProcessKeyboardEvent(
+    XKeyEvent  *event,
+    Widget widget,
+    XtPerDisplayInput pdi)
+{
+    XtDevice		device = &pdi->keyboard;
+    XtServerGrabPtr	newGrab, devGrab = &device->grab;
+    XtServerGrabRec	prevGrabRec;
+    XtServerGrabType	prevGrabType = device->grabType;
+    Widget		dspWidget = NULL;
+    Boolean		deactivateGrab = FALSE;
+
+    prevGrabRec = *devGrab;
+
+    switch (event->type)
+      {
+	case KeyPress:
+	  {
+	      if (event->keycode != 0 && /* Xlib XIM composed input */
+		  !IsServerGrab(device->grabType) &&
+		  (newGrab = CheckServerGrabs((XEvent*)event,
+					      pdi->trace,
+					      pdi->traceDepth)))
+		{
+		    /*
+		     * honor pseudo-grab from prior event by X
+		     * unlocking keyboard. Not Xt Unlock !
+		     */
+		    if (IsPseudoGrab(prevGrabType))
+		      XUngrabKeyboard(XtDisplay(newGrab->widget),
+				      event->time);
+		    else
+		      {
+			  /* Activate the grab */
+			  device->grab = *newGrab;
+			  pdi->activatingKey = event->keycode;
+			  device->grabType = XtPassiveServerGrab;
+		      }
+		}
+	    }
+	  break;
+
+	case KeyRelease:
+	  {
+	      if (IsEitherPassiveGrab(device->grabType) &&
+		  (event->keycode == pdi->activatingKey))
+		deactivateGrab = TRUE;
+	  }
+	  break;
+      }
+    dspWidget = FindKeyDestination(widget, event,
+				   &prevGrabRec, prevGrabType,
+				   devGrab, device->grabType,
+				   pdi);
+    if (deactivateGrab)
+      {
+	  /* Deactivate the grab */
+	  device->grabType = XtNoServerGrab;
+	  pdi->activatingKey = 0;
+      }
+    return dspWidget;
+}
+
+static Widget GetShell(Widget widget)
+{
+    Widget	shell;
+
+    for (shell = widget;
+	 shell && !XtIsShell(shell);
+	 shell = XtParent(shell)){}
+    return shell;
+}
+
+
+/*
+ * Check that widget really has Xt focus due to it having recieved an
+ * event
+ */
+typedef enum {NotActive = 0, IsActive, IsTarget} ActiveType;
+static ActiveType InActiveSubtree(Widget widget)
+{
+    Boolean		isTarget;
+    ActiveType		retval;
+
+    LOCK_PROCESS;
+    if (!pathTraceDepth || widget != pathTrace[0]) {
+	_XtFillAncestorList(&pathTrace,
+			    &pathTraceMax,
+			    &pathTraceDepth,
+			    widget,
+			    NULL);
+    }
+    if (widget == _FindFocusWidget(widget,
+				   pathTrace,
+				   pathTraceDepth,
+				   TRUE,
+				   &isTarget))
+	retval = (isTarget ? IsTarget : IsActive);
+    else
+	retval = NotActive;
+    UNLOCK_PROCESS;
+    return retval;
+}
+
+
+
+
+/* ARGSUSED */
+void _XtHandleFocus(
+    Widget widget,
+    XtPointer client_data,	/* child who wants focus */
+    XEvent *event,
+    Boolean *cont)		/* unused */
+{
+    XtPerDisplayInput 	pdi = _XtGetPerDisplayInput(XtDisplay(widget));
+    XtPerWidgetInput	pwi = (XtPerWidgetInput)client_data;
+    XtGeneology		oldFocalPoint = pwi->focalPoint;
+    XtGeneology		newFocalPoint = pwi->focalPoint;
+
+    switch( event->type ) {
+
+      case KeyPress:
+      case KeyRelease:
+	/*
+	 * We're getting the keyevents used to guarantee propagating
+         * child interest ala ForwardEvent in R3
+	 */
+	return;
+
+      case EnterNotify:
+      case LeaveNotify:
+
+	/*
+	 * If operating in a focus driven model, then enter and
+	 * leave events do not affect the keyboard focus.
+	 */
+	if ((event->xcrossing.detail != NotifyInferior)
+	    &&	(event->xcrossing.focus))
+	  {
+	      switch (oldFocalPoint)
+		{
+		  case XtMyAncestor:
+		    if (event->type == LeaveNotify)
+		      newFocalPoint = XtUnrelated;
+		    break;
+		  case XtUnrelated:
+		    if (event->type == EnterNotify)
+		      newFocalPoint = XtMyAncestor;
+		    break;
+		  case XtMySelf:
+		    break;
+		  case XtMyDescendant:
+		    break;
+
+		}
+	  }
+	break;
+      case FocusIn:
+	switch (event->xfocus.detail)
+	  {
+	    case NotifyNonlinear:
+	    case NotifyAncestor:
+	    case NotifyInferior:
+	      newFocalPoint = XtMySelf;
+	      break;
+	    case NotifyNonlinearVirtual:
+	    case NotifyVirtual:
+	      newFocalPoint = XtMyDescendant;
+	      break;
+	    case NotifyPointer:
+	      newFocalPoint = XtMyAncestor;
+	      break;
+	  }
+	break;
+      case FocusOut:
+	switch (event->xfocus.detail)
+	  {
+	    case NotifyPointer:
+	    case NotifyNonlinear:
+	    case NotifyAncestor:
+	    case NotifyNonlinearVirtual:
+	    case NotifyVirtual:
+	      newFocalPoint = XtUnrelated;
+	      break;
+	    case NotifyInferior:
+	      newFocalPoint = XtMyDescendant;
+	      return;
+	      break;
+	  }
+	break;
+    }
+
+    if (newFocalPoint != oldFocalPoint)
+      {
+	  Boolean 	add;
+	  Widget	descendant = pwi->focusKid;
+
+	  pwi->focalPoint = newFocalPoint;
+
+	  if ((oldFocalPoint == XtUnrelated) &&
+	      InActiveSubtree(widget) != NotActive)
+	    {
+		pdi->focusWidget = NULL; /* invalidate the cache */
+		pwi->haveFocus = TRUE;
+		add = TRUE;
+	    }
+	  else if (newFocalPoint == XtUnrelated)
+	    {
+		pdi->focusWidget = NULL; /* invalidate the cache */
+		pwi->haveFocus = FALSE;
+		add = FALSE;
+	    }
+	  else
+	    return;
+
+	  if (descendant)
+	    {
+		if (add)
+		  {
+		      _XtSendFocusEvent(descendant, FocusIn);
+		  }
+		else
+		  {
+		      _XtSendFocusEvent(descendant, FocusOut);
+		  }
+	    }
+      }
+}
+
+
+static void AddFocusHandler(
+    Widget widget,
+    Widget descendant,
+    XtPerWidgetInput pwi,
+    XtPerWidgetInput psi,
+    XtPerDisplayInput pdi,
+    EventMask oldEventMask)
+{
+    EventMask	 	eventMask, targetEventMask;
+    Widget		target;
+
+    /*
+     * widget must now select for key events if the descendant is
+     * interested in them.
+     *
+     * shell borders are not occluded by the child, they're occluded
+     * by reparenting window managers. !!!
+     */
+    target = descendant ? _GetWindowedAncestor(descendant) : NULL;
+    targetEventMask = XtBuildEventMask(target);
+    eventMask = targetEventMask & (KeyPressMask | KeyReleaseMask);
+    eventMask |= FocusChangeMask | EnterWindowMask | LeaveWindowMask;
+
+    if (oldEventMask) {
+	oldEventMask &= KeyPressMask | KeyReleaseMask;
+	oldEventMask |= FocusChangeMask | EnterWindowMask | LeaveWindowMask;
+
+	if (oldEventMask != eventMask)
+	    XtRemoveEventHandler(widget, (oldEventMask & ~eventMask),
+				 False, _XtHandleFocus, (XtPointer)pwi);
+    }
+
+    if (oldEventMask != eventMask)
+	XtAddEventHandler(widget, eventMask, False,
+			  _XtHandleFocus, (XtPointer)pwi);
+
+    /* What follows is too much grief to go through if the
+     * target doesn't actually care about focus change events,
+     * so just invalidate the focus cache & refill it when
+     * the next input event actually arrives.
+     */
+
+    if (!(targetEventMask & FocusChangeMask)) {
+	pdi->focusWidget = NULL;
+	return;
+    }
+
+    if (XtIsRealized(widget) && !pwi->haveFocus) {
+	if (psi->haveFocus) {
+	    Window root, child;
+	    int root_x, root_y, win_x, win_y;
+	    int left, right, top, bottom;
+	    unsigned int modMask;
+	    ActiveType act;
+
+	    /*
+	     * If the shell has the focus but the source widget
+	     * doesn't, it may only be because the source widget
+	     * wasn't previously tracking focus or crossing events.
+	     * If the target wants focus events, we have to
+	     * now determine whether the source has the focus.
+	     */
+
+	    if ((act = InActiveSubtree(widget)) == IsTarget)
+		pwi->haveFocus = TRUE;
+	    else if (act == IsActive) {
+		/*
+		 * An ancestor contains the focus, so if source
+		 * contains the pointer, then source has the focus.
+		 */
+
+		if (XQueryPointer(XtDisplay(widget), XtWindow(widget),
+				  &root, &child,
+				  &root_x, &root_y, &win_x, &win_y, &modMask))
+		{
+		    /* We need to take borders into consideration */
+		    left = top = -((int) widget->core.border_width);
+		    right = (int) (widget->core.width + (widget->core.border_width << 1));
+		    bottom = (int) (widget->core.height + (widget->core.border_width << 1));
+
+		    if (win_x >= left && win_x < right &&
+			win_y >= top && win_y < bottom)
+			pwi->haveFocus = TRUE;
+		}
+	    }
+	}
+    }
+    if (pwi->haveFocus) {
+	  pdi->focusWidget = NULL; /* invalidate the cache */
+	  _XtSendFocusEvent(target, FocusIn);
+    }
+}
+
+
+/* ARGSUSED */
+static void QueryEventMask(
+    Widget widget,		/* child who gets focus */
+    XtPointer client_data,	/* ancestor giving it */
+    XEvent *event,
+    Boolean *cont)		/* unused */
+{
+    /* widget was once the target of an XtSetKeyboardFocus but
+     * was unrealized at the time.   Make sure ancestor still wants
+     * focus set here then install the handler now that we know the
+     * complete event mask.
+     */
+    Widget ancestor = (Widget)client_data;
+    XtPerWidgetInput pwi = _XtGetPerWidgetInput(ancestor, FALSE);
+    Widget target = pwi->queryEventDescendant;
+
+    /* use of 'target' is non-standard hackery; allows focus to non-widget */
+    if (pwi && (pwi->focusKid == target)) {
+	AddFocusHandler(ancestor, target, pwi,
+			_XtGetPerWidgetInput(GetShell(ancestor), TRUE),
+			_XtGetPerDisplayInput(XtDisplay(ancestor)),
+			(EventMask)0);
+    }
+    XtRemoveEventHandler(widget, XtAllEvents, True,
+			 QueryEventMask, client_data);
+    pwi->map_handler_added = FALSE;
+}
+
+
+/* ARGSUSED */
+static void FocusDestroyCallback(
+    Widget  widget,
+    XtPointer closure,		/* Widget */
+    XtPointer call_data)
+{
+    XtSetKeyboardFocus((Widget)closure, NULL);
+}
+
+void XtSetKeyboardFocus(
+    Widget widget,
+    Widget descendant)
+{
+    XtPerDisplayInput pdi;
+    XtPerWidgetInput pwi;
+    Widget oldDesc, oldTarget, target, hookobj;
+    WIDGET_TO_APPCON(widget);
+
+    LOCK_APP(app);
+    LOCK_PROCESS;
+    pdi = _XtGetPerDisplayInput(XtDisplay(widget));
+    pwi = _XtGetPerWidgetInput(widget, TRUE);
+    oldDesc = pwi->focusKid;
+
+    if (descendant == widget) descendant = (Widget)None;
+
+    target = descendant ? _GetWindowedAncestor(descendant) : NULL;
+    oldTarget = oldDesc ? _GetWindowedAncestor(oldDesc) : NULL;
+
+    if (descendant != oldDesc) {
+
+	/* update the forward path */
+	pwi->focusKid = descendant;
+
+
+	/* all the rest handles focus ins and focus outs and misc gunk */
+
+	if (oldDesc) {
+	    /* invalidate FindKeyDestination's ancestor list */
+	    if (pseudoTraceDepth && oldTarget == pseudoTrace[0])
+		pseudoTraceDepth = 0;
+
+	    XtRemoveCallback(oldDesc, XtNdestroyCallback,
+			     FocusDestroyCallback, (XtPointer)widget);
+
+	    if (!oldTarget->core.being_destroyed) {
+		if (pwi->map_handler_added) {
+		    XtRemoveEventHandler(oldTarget, XtAllEvents, True,
+					 QueryEventMask, (XtPointer)widget);
+		    pwi->map_handler_added = FALSE;
+		}
+		if (pwi->haveFocus) {
+		    _XtSendFocusEvent( oldTarget, FocusOut);
+		}
+	    }
+	    else if (pwi->map_handler_added) {
+		pwi->map_handler_added = FALSE;
+	    }
+
+	    if (pwi->haveFocus)
+		pdi->focusWidget = NULL; /* invalidate cache */
+
+	    /*
+	     * If there was a forward path then remove the handler if
+	     * the path is being set to null and it isn't a shell.
+	     * shells always have a handler for tracking focus for the
+	     * hierarchy.
+	     *
+	     * Keep the pwi record on the assumption that the client
+	     * will continue to dynamically assign focus for this widget.
+	     */
+	    if (!XtIsShell(widget) && !descendant) {
+	      XtRemoveEventHandler(widget, XtAllEvents, True,
+				   _XtHandleFocus, (XtPointer)pwi);
+	      pwi->haveFocus = FALSE;
+	  }
+	}
+
+	if (descendant) {
+	    Widget shell = GetShell(widget);
+	    XtPerWidgetInput psi = _XtGetPerWidgetInput(shell, TRUE);
+	    XtAddCallback (descendant, XtNdestroyCallback,
+			   FocusDestroyCallback, (XtPointer) widget);
+
+	    AddFocusHandler(widget, descendant, pwi, psi, pdi,
+			    oldTarget ? XtBuildEventMask(oldTarget) : 0);
+
+	    if (widget != shell)
+		XtAddEventHandler(
+			shell,
+			FocusChangeMask | EnterWindowMask | LeaveWindowMask,
+			False,
+			_XtHandleFocus,
+			(XtPointer)psi
+		       );
+
+	    if (! XtIsRealized(target)) {
+		XtAddEventHandler(target, (EventMask)StructureNotifyMask,
+				  False, QueryEventMask, (XtPointer)widget);
+		pwi->map_handler_added = TRUE;
+		pwi->queryEventDescendant = descendant;
+	    }
+	}
+    }
+    hookobj = XtHooksOfDisplay(XtDisplay(widget));
+    if (XtHasCallbacks(hookobj, XtNchangeHook) == XtCallbackHasSome) {
+	XtChangeHookDataRec call_data;
+
+	call_data.type = XtHsetKeyboardFocus;
+	call_data.widget = widget;
+	call_data.event_data = (XtPointer) descendant;
+	XtCallCallbackList(hookobj,
+		((HookObject)hookobj)->hooks.changehook_callbacks,
+		(XtPointer)&call_data);
+    }
+    UNLOCK_PROCESS;
+    UNLOCK_APP(app);
+}