dix: move focus handling into enterleave.c.

This commit moves the focus handling from events.c into enterleave.c and
implements a model similar to the core enter/leave model.
For a full description of the model, see:
http://lists.freedesktop.org/archives/xorg/2008-December/041740.html

This commit also gets rid of the focusinout array in the WindowRec, ditching
it in favour of a local array that keeps the current focus window for each
device.

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>

1 files changed, 793 insertions, 7 deletions

diff --git a/dix/enterleave.c b/dix/enterleave.c
index d01597aac..1a5f1b598 100644
--- a/dix/enterleave.c
+++ b/dix/enterleave.c
@@ -30,19 +30,24 @@
 
 #include <X11/X.h>
 #include "windowstr.h"
+#include "scrnintstr.h"
 #include "exglobals.h"
 #include "enterleave.h"
 
-/* @file This file describes the model for sending core enter/leave events in
- * the case of multiple pointers.
- * Since we can't send more than one Enter or Leave event per window
- * to a core client without confusing it, this is a rather complicated
+/* @file This file describes the model for sending core enter/leave events and
+ * focus in/out in the case of multiple pointers/keyboard foci
+ * Since we can't send more than one Enter or Leave/Focus in or out event per
+ * window to a core client without confusing it, this is a rather complicated
  * approach.
  *
  * For a full description of the enter/leave model from a window's
  * perspective, see
  * http://lists.freedesktop.org/archives/xorg/2008-August/037606.html
  *
+ * For a full description of the focus in/out model from a window's
+ * perspective, see
+ * http://lists.freedesktop.org/archives/xorg/2008-December/041740.html
+ *
  * Additional notes:
  * -) The core protocol spec says that "In a LeaveNotify event, if a child of the
  * event window contains the initial position of the pointer, then the child
@@ -52,6 +57,12 @@
  *
  * By inference, this means that only NotifyVirtual or NotifyNonlinearVirtual
  * events may have a subwindow set to other than None.
+ *
+ * -) NotifyPointer events may be sent if the focus changes from window A to
+ * B. The assumption used in this model is that NotifyPointer events are only
+ * sent for the pointer paired with the keyboard that is involved in the focus
+ * events. For example, if F(W) changes because of keyboard 2, then
+ * NotifyPointer events are only sent for pointer 2.
  */
 
 static WindowPtr PointerWindows[MAXDEVICES];
@@ -73,6 +84,10 @@ HasPointer(WindowPtr win)
     return FALSE;
 }
 
+/**
+ * Return TRUE if at least one keyboard focus is set to @win (excluding
+ * descendants of win).
+ */
 static BOOL
 HasFocus(WindowPtr win)
 {
@@ -85,6 +100,15 @@ HasFocus(WindowPtr win)
 }
 
 /**
+ * Return the window the device @dev is currently on.
+ */
+static WindowPtr
+PointerWin(DeviceIntPtr dev)
+{
+    return PointerWindows[dev->id];
+}
+
+/**
  * Search for the first window below @win that has a pointer directly within
  * it's boundaries (excluding boundaries of its own descendants).
  *
@@ -105,7 +129,7 @@ FirstPointerChild(WindowPtr win)
 }
 
 /**
- * Search for the first window below @win that has a pointer directly within
+ * Search for the first window below @win that has a focus directly within
  * it's boundaries (excluding boundaries of its own descendants).
  *
  * @return The child window that has the pointer within its boundaries or
@@ -125,8 +149,6 @@ FirstFocusChild(WindowPtr win)
     return NULL;
 }
 
-
-
 /**
  * Set the presence flag for @dev to mark that it is now in @win.
  */
@@ -581,3 +603,767 @@ DoEnterLeaveEvents(DeviceIntPtr pDev,
     CoreEnterLeaveEvents(pDev, fromWin, toWin, mode);
     DeviceEnterLeaveEvents(pDev, fromWin, toWin, mode);
 }
+
+/**
+ * Send focus out events to all windows between @child and @ancestor.
+ * Events are sent running up the hierarchy.
+ */
+static void
+DeviceFocusOutEvents(DeviceIntPtr dev,
+                     WindowPtr child,
+                     WindowPtr ancestor,
+                     int mode,
+                     int detail)
+{
+    WindowPtr  win;
+
+    if (ancestor == child)
+	return;
+    for (win = child->parent; win != ancestor; win = win->parent)
+        DeviceFocusEvent(dev, DeviceFocusOut, mode, detail, win);
+}
+
+
+/**
+ * Send enter notifies to all windows between @ancestor and @child (excluding
+ * both). Events are sent running up the window hierarchy. This function
+ * recurses.
+ */
+static void
+DeviceFocusInEvents(DeviceIntPtr dev,
+                    WindowPtr ancestor,
+                    WindowPtr child,
+                    int mode,
+                    int detail)
+{
+    WindowPtr	parent = child->parent;
+
+    if (ancestor == parent || !parent)
+	return;
+    DeviceFocusInEvents(dev, ancestor, parent, mode, detail);
+    DeviceFocusEvent(dev, DeviceFocusIn, mode, detail, parent);
+}
+
+/**
+ * Send FocusIn events to all windows between @ancestor and @child (excluding
+ * both). Events are sent running down the window hierarchy. This function
+ * recurses.
+ */
+static void
+CoreFocusInEvents(DeviceIntPtr dev,
+                  WindowPtr ancestor,
+                  WindowPtr child,
+                  int mode,
+                  int detail)
+{
+    WindowPtr	parent = child->parent;
+    if (ancestor == parent)
+	return;
+    CoreFocusInEvents(dev, ancestor, parent, mode, detail);
+
+
+    /* Case 3:
+     A is above W, B is a descendant
+
+      Classically: The move generates an FocusIn on W with a detail of
+        Virtual or NonlinearVirtual
+
+     MPX:
+        Case 3A: There is at least one other focus on W itself
+          F(W) doesn't change, so the event should be suppressed
+        Case 3B: Otherwise, if there is at least one other focus in a
+          descendant
+          F(W) stays on the same descendant, or changes to a different
+          descendant. The event should be suppressed.
+        Case 3C: Otherwise:
+          F(W) moves from a window above W to a descendant. The detail may
+          need to be changed from Virtual to NonlinearVirtual depending
+          on the previous F(W). */
+
+    if (!HasFocus(parent) && !FirstFocusChild(parent))
+            CoreFocusEvent(dev, FocusIn, mode, detail, parent);
+}
+
+static void
+CoreFocusOutEvents(DeviceIntPtr dev,
+                   WindowPtr child,
+                   WindowPtr ancestor,
+                   int mode,
+                   int detail)
+{
+    WindowPtr  win;
+
+    if (ancestor == child)
+        return;
+
+    for (win = child->parent; win != ancestor; win = win->parent)
+    {
+        /*Case 7:
+        A is a descendant of W, B is above W
+
+        Classically: A FocusOut is generated on W with a detail of Virtual
+          or NonlinearVirtual.
+
+        MPX:
+            Case 3A: There is at least one other focus on W itself
+              F(W) doesn't change, the event should be suppressed.
+            Case 3B: Otherwise, if there is at least one other focus in a
+            descendant
+             F(W) stays on the same descendant, or changes to a different
+              descendant. The event should be suppressed.
+            Case 3C: Otherwise:
+              F(W) changes from the descendant of W to a window above W.
+              The detail may need to be changed from Virtual to NonlinearVirtual
+              or vice-versa depending on the new P(W).*/
+
+        /* If one window has a focus or a child with a focuspointer, skip some
+         * work and exit. */
+        if (HasFocus(win) || FirstFocusChild(win))
+            return;
+
+        CoreFocusEvent(dev, FocusOut, mode, detail, win);
+    }
+}
+
+/**
+ * Send FocusOut(NotifyPointer) events from the current pointer window (which
+ * is a descendant of @pwin_parent) up to (excluding) @pwin_parent.
+ *
+ * NotifyPointer events are only sent for the device paired with @dev.
+ *
+ * If the current pointer window is a descendat of @exclude or an ancestor of
+ * @exclude, no events are sent. Note: If the current pointer IS @exclude,
+ * events are sent!
+ */
+static void
+CoreFocusOutNotifyPointerEvents(DeviceIntPtr dev,
+                                WindowPtr pwin_parent,
+                                WindowPtr exclude,
+                                int mode,
+                                int inclusive)
+{
+    WindowPtr P, stopAt;
+
+    P = PointerWin(GetPairedDevice(dev));
+
+    if (!P)
+        return;
+    if (!IsParent(pwin_parent, P))
+        if (!(pwin_parent == P && inclusive))
+            return;
+
+    if (exclude != None && exclude != PointerRootWin &&
+        (IsParent(exclude, P) || IsParent(P, exclude)))
+        return;
+
+    stopAt = (inclusive) ? pwin_parent->parent : pwin_parent;
+
+    for (; P && P != stopAt; P = P->parent)
+        CoreFocusEvent(dev, FocusOut, mode, NotifyPointer, P);
+}
+
+/**
+ * DO NOT CALL DIRECTLY.
+ * Recursion helper for CoreFocusInNotifyPointerEvents.
+ */
+static void
+CoreFocusInRecurse(DeviceIntPtr dev,
+                   WindowPtr win,
+                   WindowPtr stopAt,
+                   int mode,
+                   int inclusive)
+{
+    if ((!inclusive && win == stopAt) || !win)
+        return;
+
+    CoreFocusInRecurse(dev, win->parent, stopAt, mode, inclusive);
+    CoreFocusEvent(dev, FocusIn, mode, NotifyPointer, win);
+}
+
+
+/**
+ * Send FocusIn(NotifyPointer) events from @pwin_parent down to
+ * including the current pointer window (which is a descendant of @pwin_parent).
+ * If @inclusive is TRUE, @pwin_parent will receive the event too.
+ *
+ * @pwin is the pointer window.
+ *
+ * If the current pointer window is a child of @exclude, no events are sent.
+ */
+static void
+CoreFocusInNotifyPointerEvents(DeviceIntPtr dev,
+                               WindowPtr pwin_parent,
+                               WindowPtr exclude,
+                               int mode,
+                               int inclusive)
+{
+    WindowPtr P;
+
+    P = PointerWin(GetPairedDevice(dev));
+
+    if (!P || P == exclude || (pwin_parent != P && !IsParent(pwin_parent, P)))
+        return;
+
+    if (exclude != None && (IsParent(exclude, P) || IsParent(P, exclude)))
+        return;
+
+    CoreFocusInRecurse(dev, P, pwin_parent, mode, inclusive);
+}
+
+
+/**
+ * Focus of @dev moves from @A to @B and @A neither a descendant of @B nor is
+ * @B a descendant of @A.
+ */
+static void
+CoreFocusNonLinear(DeviceIntPtr dev,
+                   WindowPtr A,
+                   WindowPtr B,
+                   int mode)
+{
+    WindowPtr X = CommonAncestor(A, B);
+
+    /* Case 4:
+     A is W, B is above W
+
+    Classically: The change generates a FocusOut on W with a detail of
+       Ancestor or Nonlinear
+
+     MPX:
+        Case 3A: There is at least one other focus on W itself
+          F(W) doesn't change, the event should be suppressed
+        Case 3B: Otherwise, if there is at least one other focus in a
+        descendant of W
+          F(W) changes from W to a descendant of W. The detail field
+          is set to Inferior
+        Case 3C: Otherwise:
+          The focus window moves from W to a window above W.
+          The detail may need to be changed from Ancestor to Nonlinear or
+          vice versa depending on the the new F(W)
+     */
+
+    if (!HasFocus(A))
+    {
+        WindowPtr child = FirstFocusChild(A);
+        if (child)
+        {
+            /* NotifyPointer P-A unless P is child or below*/
+            CoreFocusOutNotifyPointerEvents(dev, A, child, mode, FALSE);
+            CoreFocusEvent(dev, FocusOut, mode, NotifyInferior, A);
+        } else
+        {
+            /* NotifyPointer P-A */
+            CoreFocusOutNotifyPointerEvents(dev, A, None, mode, FALSE);
+            CoreFocusEvent(dev, FocusOut, mode, NotifyNonlinear, A);
+        }
+    }
+
+
+    CoreFocusOutEvents(dev, A, X, mode, NotifyNonlinearVirtual);
+
+    /*
+      Case 9:
+        A is a descendant of W, B is a descendant of W
+
+        Classically: No events are generated on W
+        MPX: The focus window stays the same or moves to a different
+          descendant of W. No events should be generated on W.
+
+
+       Therefore, no event to X.
+    */
+
+    CoreFocusInEvents(dev, X, B, mode, NotifyNonlinearVirtual);
+
+    /* Case 2:
+      A is above W, B=W
+
+      Classically: The move generates an EnterNotify on W with a detail of
+        Ancestor or Nonlinear
+
+      MPX:
+        Case 2A: There is at least one other focus on W itself
+          F(W) doesn't change, so the event should be suppressed
+        Case 2B: Otherwise, if there is at least one other focus in a
+          descendant
+          F(W) moves from a descendant to W. detail is changed to Inferior.
+        Case 2C: Otherwise:
+          F(W) changes from a window above W to W itself.
+          The detail may need to be changed from Ancestor to Nonlinear
+          or vice-versa depending on the previous F(W). */
+
+     if (!HasFocus(B))
+     {
+         WindowPtr child = FirstFocusChild(B);
+         if (child)
+         {
+             CoreFocusEvent(dev, FocusIn, mode, NotifyInferior, B);
+             /* NotifyPointer B-P unless P is child or below. */
+             CoreFocusInNotifyPointerEvents(dev, B, child, mode, FALSE);
+         } else {
+             CoreFocusEvent(dev, FocusIn, mode, NotifyNonlinear, B);
+             /* NotifyPointer B-P unless P is child or below. */
+             CoreFocusInNotifyPointerEvents(dev, B, None, mode, FALSE);
+         }
+     }
+}
+
+
+/**
+ * Focus of @dev moves from @A to @B and @A is a descendant of @B.
+ */
+static void
+CoreFocusToAncestor(DeviceIntPtr dev,
+                    WindowPtr A,
+                    WindowPtr B,
+                    int mode)
+{
+    /* Case 4:
+     A is W, B is above W
+
+    Classically: The change generates a FocusOut on W with a detail of
+       Ancestor or Nonlinear
+
+     MPX:
+        Case 3A: There is at least one other focus on W itself
+          F(W) doesn't change, the event should be suppressed
+        Case 3B: Otherwise, if there is at least one other focus in a
+        descendant of W
+          F(W) changes from W to a descendant of W. The detail field
+          is set to Inferior
+        Case 3C: Otherwise:
+          The focus window moves from W to a window above W.
+          The detail may need to be changed from Ancestor to Nonlinear or
+          vice versa depending on the the new F(W)
+     */
+    if (!HasFocus(A))
+    {
+        WindowPtr child = FirstFocusChild(A);
+        if (child)
+        {
+            /* NotifyPointer P-A unless P is child or below*/
+            CoreFocusOutNotifyPointerEvents(dev, A, child, mode, FALSE);
+            CoreFocusEvent(dev, FocusOut, mode, NotifyInferior, A);
+        } else
+            CoreFocusEvent(dev, FocusOut, mode, NotifyAncestor, A);
+    }
+
+    CoreFocusOutEvents(dev, A, B, mode, NotifyVirtual);
+
+    /* Case 8:
+    A is a descendant of W, B is W
+
+    Classically: A FocusOut is generated on W with a detail of
+        NotifyInferior
+
+    MPX:
+        Case 3A: There is at least one other focus on W itself
+          F(W) doesn't change, the event should be suppressed
+        Case 3B: Otherwise:
+          F(W) changes from a descendant to W itself. */
+
+    if (!HasFocus(B))
+    {
+        CoreFocusEvent(dev, FocusIn, mode, NotifyInferior, B);
+        /* NotifyPointer B-P unless P is A or below. */
+        CoreFocusInNotifyPointerEvents(dev, B, A, mode, FALSE);
+    }
+}
+
+/**
+ * Focus of @dev moves from @A to @B and @B is a descendant of @A.
+ */
+static void
+CoreFocusToDescendant(DeviceIntPtr dev,
+                      WindowPtr A,
+                      WindowPtr B,
+                      int mode)
+{
+    /* Case 6:
+    A is W, B is a descendant of W
+
+    Classically: A FocusOut is generated on W with a detail of
+       NotifyInferior
+
+    MPX:
+        Case 3A: There is at least one other focus on W itself
+          F(W) doesn't change, the event should be suppressed
+        Case 3B: Otherwise:
+          F(W) changes from W to a descendant of W. */
+
+    if (!HasFocus(A))
+    {
+        /* NotifyPointer P-A unless P is B or below*/
+        CoreFocusOutNotifyPointerEvents(dev, A, B, mode, FALSE);
+        CoreFocusEvent(dev, FocusOut, mode, NotifyInferior, A);
+    }
+
+
+    CoreFocusInEvents(dev, A, B, mode, NotifyVirtual);
+
+    /* Case 2:
+      A is above W, B=W
+
+      Classically: The move generates an FocusIn on W with a detail of
+        Ancestor or Nonlinear
+
+      MPX:
+        Case 2A: There is at least one other focus on W itself
+          F(W) doesn't change, so the event should be suppressed
+        Case 2B: Otherwise, if there is at least one other focus in a
+          descendant
+          F(W) moves from a descendant to W. detail is changed to Inferior.
+        Case 2C: Otherwise:
+          F(W) changes from a window above W to W itself.
+          The detail may need to be changed from Ancestor to Nonlinear
+          or vice-versa depending on the previous F(W). */
+
+     if (!HasFocus(B))
+     {
+         WindowPtr child = FirstFocusChild(B);
+         if (child)
+         {
+             CoreFocusEvent(dev, FocusIn, mode, NotifyInferior, B);
+             /* NotifyPointer B-P unless P is child or below. */
+             CoreFocusInNotifyPointerEvents(dev, B, child, mode, FALSE);
+         } else
+             CoreFocusEvent(dev, FocusIn, mode, NotifyAncestor, B);
+     }
+}
+
+static BOOL
+HasOtherPointer(WindowPtr win, DeviceIntPtr exclude)
+{
+    int i;
+
+    for (i = 0; i < MAXDEVICES; i++)
+        if (i != exclude->id && PointerWindows[i] == win)
+            return TRUE;
+
+    return FALSE;
+}
+
+/**
+ * Focus moves from PointerRoot to None or from None to PointerRoot.
+ * Assumption: Neither A nor B are valid windows.
+ */
+static void
+CoreFocusPointerRootNoneSwitch(DeviceIntPtr dev,
+                               WindowPtr A, /* PointerRootWin or NoneWin */
+                               WindowPtr B, /* NoneWin or PointerRootWin */
+                               int mode)
+{
+    WindowPtr root;
+    int i;
+    int nscreens = screenInfo.numScreens;
+
+#ifdef PANORAMIX
+    if (!noPanoramiXExtension)
+        nscreens = 1;
+#endif
+
+    for (i = 0; i < nscreens; i++)
+    {
+        root = WindowTable[i];
+        if (!HasOtherPointer(root, GetPairedDevice(dev)) && !FirstFocusChild(root))
+        {
+            /* If pointer was on PointerRootWin and changes to NoneWin, and
+             * the pointer paired with @dev is below the current root window,
+             * do a NotifyPointer run. */
+            if (dev->focus && dev->focus->win == PointerRootWin &&
+                B != PointerRootWin)
+            {
+                WindowPtr ptrwin = PointerWin(GetPairedDevice(dev));
+                if (ptrwin && IsParent(root, ptrwin))
+                    CoreFocusOutNotifyPointerEvents(dev, root, None, mode, TRUE);
+            }
+            CoreFocusEvent(dev, FocusOut, mode, ((int)A) ? NotifyPointerRoot : NotifyDetailNone, root);
+            CoreFocusEvent(dev, FocusIn, mode, ((int)B) ? NotifyPointerRoot : NotifyDetailNone, root);
+            if (B == PointerRootWin)
+                CoreFocusInNotifyPointerEvents(dev, root, None, mode, TRUE);
+        }
+
+    }
+}
+
+/**
+ * Focus moves from window @A to PointerRoot or to None.
+ * Assumption: @A is a valid window and not PointerRoot or None.
+ */
+static void
+CoreFocusToPointerRootOrNone(DeviceIntPtr dev,
+                       WindowPtr A,
+                       WindowPtr B, /* PointerRootWin or NoneWin */
+                       int mode)
+{
+    WindowPtr root;
+    int i;
+    int nscreens = screenInfo.numScreens;
+
+#ifdef PANORAMIX
+    if (!noPanoramiXExtension)
+        nscreens = 1;
+#endif
+
+    if (!HasFocus(A))
+    {
+        WindowPtr child = FirstFocusChild(A);
+        if (child)
+        {
+            /* NotifyPointer P-A unless P is B or below*/
+            CoreFocusOutNotifyPointerEvents(dev, A, B, mode, FALSE);
+            CoreFocusEvent(dev, FocusOut, mode, NotifyInferior, A);
+        } else {
+            /* NotifyPointer P-A */
+            CoreFocusOutNotifyPointerEvents(dev, A, None, mode, FALSE);
+            CoreFocusEvent(dev, FocusOut, mode, NotifyNonlinear, A);
+        }
+    }
+
+    /* NullWindow means we include the root window */
+    CoreFocusOutEvents(dev, A, NullWindow, mode, NotifyNonlinearVirtual);
+
+    for (i = 0; i < nscreens; i++)
+    {
+        root = WindowTable[i];
+        if (!HasFocus(root) && !FirstFocusChild(root))
+        {
+            CoreFocusEvent(dev, FocusIn, mode, ((int)B) ? NotifyPointerRoot : NotifyDetailNone, root);
+            if (B == PointerRootWin)
+                CoreFocusInNotifyPointerEvents(dev, root, None, mode, TRUE);
+        }
+    }
+}
+
+/**
+ * Focus moves from PointerRoot or None to a window @to.
+ * Assumption: @to is a valid window and not PointerRoot or None.
+ */
+static void
+CoreFocusFromPointerRootOrNone(DeviceIntPtr dev,
+                               WindowPtr A, /* PointerRootWin or NoneWin */
+                               WindowPtr B,
+                               int mode)
+{
+    WindowPtr root;
+    int i;
+    int nscreens = screenInfo.numScreens;
+
+#ifdef PANORAMIX
+    if (!noPanoramiXExtension)
+        nscreens = 1;
+#endif
+
+    for (i = 0; i < nscreens; i++)
+    {
+        root = WindowTable[i];
+        if (!HasFocus(root) && !FirstFocusChild(root))
+        {
+            /* If pointer was on PointerRootWin and changes to NoneWin, and
+             * the pointer paired with @dev is below the current root window,
+             * do a NotifyPointer run. */
+            if (dev->focus && dev->focus->win == PointerRootWin &&
+                B != PointerRootWin)
+            {
+                WindowPtr ptrwin = PointerWin(GetPairedDevice(dev));
+                if (ptrwin)
+                    CoreFocusOutNotifyPointerEvents(dev, root, None, mode, TRUE);
+            }
+            CoreFocusEvent(dev, FocusOut, mode, ((int)A) ? NotifyPointerRoot : NotifyDetailNone, root);
+        }
+    }
+
+    root = B; /* get B's root window */
+    while(root->parent)
+        root = root->parent;
+
+    if (B != root)
+    {
+        CoreFocusEvent(dev, FocusIn, mode, NotifyNonlinearVirtual, root);
+        CoreFocusInEvents(dev, root, B, mode, NotifyNonlinearVirtual);
+    }
+
+
+    if (!HasFocus(B))
+    {
+        WindowPtr child = FirstFocusChild(B);
+        if (child)
+        {
+             CoreFocusEvent(dev, FocusIn, mode, NotifyInferior, B);
+             /* NotifyPointer B-P unless P is child or below. */
+             CoreFocusInNotifyPointerEvents(dev, B, child, mode, FALSE);
+        } else {
+            CoreFocusEvent(dev, FocusIn, mode, NotifyNonlinear, B);
+            /* NotifyPointer B-P unless P is child or below. */
+            CoreFocusInNotifyPointerEvents(dev, B, None, mode, FALSE);
+        }
+    }
+
+}
+
+static void
+CoreFocusEvents(DeviceIntPtr dev,
+                WindowPtr from,
+                WindowPtr to,
+                int mode)
+{
+    if (!dev->isMaster)
+        return;
+
+    SetFocusOut(dev, from);
+
+    if (((to == NullWindow) || (to == PointerRootWin)) &&
+        ((from == NullWindow) || (from == PointerRootWin)))
+        CoreFocusPointerRootNoneSwitch(dev, from, to, mode);
+    else if ((to == NullWindow) || (to == PointerRootWin))
+        CoreFocusToPointerRootOrNone(dev, from, to, mode);
+    else if ((from == NullWindow) || (from == PointerRootWin))
+        CoreFocusFromPointerRootOrNone(dev, from, to, mode);
+    else if (IsParent(from, to))
+        CoreFocusToDescendant(dev, from, to, mode);
+    else if (IsParent(to, from))
+        CoreFocusToAncestor(dev, from, to, mode);
+    else
+        CoreFocusNonLinear(dev, from, to, mode);
+
+    SetFocusIn(dev, to);
+}
+
+#define RootWindow(dev) dev->spriteInfo->sprite->spriteTrace[0]
+
+static void
+DeviceFocusEvents(DeviceIntPtr dev,
+                  WindowPtr from,
+                  WindowPtr to,
+                  int mode)
+{
+    int out, in;		       /* for holding details for to/from
+                                          PointerRoot/None */
+    int i;
+    int nscreens = screenInfo.numScreens;
+    SpritePtr sprite  = dev->spriteInfo->sprite;
+
+    if (from == to)
+        return;
+    out = (from == NoneWin) ? NotifyDetailNone : NotifyPointerRoot;
+    in = (to == NoneWin) ? NotifyDetailNone : NotifyPointerRoot;
+    /* wrong values if neither, but then not referenced */
+
+#ifdef PANORAMIX
+    if (!noPanoramiXExtension)
+        nscreens = 1;
+#endif
+
+    if ((to == NullWindow) || (to == PointerRootWin))
+    {
+        if ((from == NullWindow) || (from == PointerRootWin))
+        {
+            if (from == PointerRootWin)
+                DeviceFocusOutEvents(dev, sprite->win, RootWindow(dev), mode,
+                        NotifyPointer);
+            /* Notify all the roots */
+            for (i = 0; i < nscreens; i++)
+                DeviceFocusEvent(dev, FocusOut, mode, out, WindowTable[i]);
+        }
+        else
+        {
+            if (IsParent(from, sprite->win))
+                DeviceFocusOutEvents(dev, sprite->win, from, mode,
+                        NotifyPointer);
+            DeviceFocusEvent(dev, FocusOut, mode, NotifyNonlinear, from);
+            /* next call catches the root too, if the screen changed */
+            DeviceFocusOutEvents(dev, from->parent, NullWindow, mode,
+                    NotifyNonlinearVirtual);
+        }
+        /* Notify all the roots */
+        for (i = 0; i < nscreens; i++)
+            DeviceFocusEvent(dev, FocusIn, mode, in, WindowTable[i]);
+        if (to == PointerRootWin)
+            DeviceFocusInEvents(dev, RootWindow(dev), sprite->win, mode, NotifyPointer);
+    }
+    else
+    {
+        if ((from == NullWindow) || (from == PointerRootWin))
+        {
+            if (from == PointerRootWin)
+                DeviceFocusOutEvents(dev, sprite->win, RootWindow(dev), mode,
+                        NotifyPointer);
+            for (i = 0; i < nscreens; i++)
+                DeviceFocusEvent(dev, FocusOut, mode, out, WindowTable[i]);
+            if (to->parent != NullWindow)
+                DeviceFocusInEvents(dev, RootWindow(dev), to, mode, NotifyNonlinearVirtual);
+            DeviceFocusEvent(dev, FocusIn, mode, NotifyNonlinear, to);
+            if (IsParent(to, sprite->win))
+                DeviceFocusInEvents(dev, to, sprite->win, mode, NotifyPointer);
+        }
+        else
+        {
+            if (IsParent(to, from))
+            {
+                DeviceFocusEvent(dev, FocusOut, mode, NotifyAncestor, from);
+                DeviceFocusOutEvents(dev, from->parent, to, mode,
+                        NotifyVirtual);
+                DeviceFocusEvent(dev, FocusIn, mode, NotifyInferior, to);
+                if ((IsParent(to, sprite->win)) &&
+                        (sprite->win != from) &&
+                        (!IsParent(from, sprite->win)) &&
+                        (!IsParent(sprite->win, from)))
+                    DeviceFocusInEvents(dev, to, sprite->win, mode, NotifyPointer);
+            }
+            else
+                if (IsParent(from, to))
+                {
+                    if ((IsParent(from, sprite->win)) &&
+                            (sprite->win != from) &&
+                            (!IsParent(to, sprite->win)) &&
+                            (!IsParent(sprite->win, to)))
+                        DeviceFocusOutEvents(dev, sprite->win, from, mode,
+                                NotifyPointer);
+                    DeviceFocusEvent(dev, FocusOut, mode, NotifyInferior, from);
+                    DeviceFocusInEvents(dev, from, to, mode, NotifyVirtual);
+                    DeviceFocusEvent(dev, FocusIn, mode, NotifyAncestor, to);
+                }
+                else
+                {
+                    /* neither from or to is child of other */
+                    WindowPtr common = CommonAncestor(to, from);
+                    /* common == NullWindow ==> different screens */
+                    if (IsParent(from, sprite->win))
+                        DeviceFocusOutEvents(dev, sprite->win, from, mode,
+                                NotifyPointer);
+                    DeviceFocusEvent(dev, FocusOut, mode, NotifyNonlinear, from);
+                    if (from->parent != NullWindow)
+                        DeviceFocusOutEvents(dev, from->parent, common, mode,
+                                NotifyNonlinearVirtual);
+                    if (to->parent != NullWindow)
+                        DeviceFocusInEvents(dev, common, to, mode, NotifyNonlinearVirtual);
+                    DeviceFocusEvent(dev, FocusIn, mode, NotifyNonlinear, to);
+                    if (IsParent(to, sprite->win))
+                        DeviceFocusInEvents(dev, to, sprite->win, mode, NotifyPointer);
+                }
+        }
+    }
+}
+
+/**
+ * Figure out if focus events are necessary and send them to the
+ * appropriate windows.
+ *
+ * @param from Window the focus moved out of.
+ * @param to Window the focus moved into.
+ */
+void
+DoFocusEvents(DeviceIntPtr pDev,
+              WindowPtr from,
+              WindowPtr to,
+              int mode)
+{
+    if (!IsKeyboardDevice(pDev))
+        return;
+
+    if (from == to)
+	return;
+
+    CoreFocusEvents(pDev, from, to, mode);
+    DeviceFocusEvents(pDev, from, to, mode);
+}