Imported nx-X11-3.1.0-1.tar.gznx-X11/3.1.0-1

Summary: Imported nx-X11-3.1.0-1.tar.gz
Keywords:

Imported nx-X11-3.1.0-1.tar.gz
into Git repository

1 files changed, 1497 insertions, 0 deletions

diff --git a/nx-X11/programs/Xserver/hw/dmx/dmxextension.c b/nx-X11/programs/Xserver/hw/dmx/dmxextension.c
new file mode 100644
index 000000000..feadb5e31
--- /dev/null
+++ b/nx-X11/programs/Xserver/hw/dmx/dmxextension.c
@@ -0,0 +1,1497 @@
+/* $XFree86$ */
+/*
+ * Copyright 2003-2004 Red Hat Inc., Durham, North Carolina.
+ *
+ * All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation on the rights to use, copy, modify, merge,
+ * publish, distribute, sublicense, and/or sell copies of the Software,
+ * and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the
+ * next paragraph) 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
+ * NON-INFRINGEMENT.  IN NO EVENT SHALL RED HAT AND/OR THEIR SUPPLIERS
+ * 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.
+ */
+
+/*
+ * Author:
+ *   Rickard E. (Rik) Faith <faith@redhat.com>
+ *   Kevin E. Martin <kem@redhat.com>
+ *
+ */
+
+/** \file
+ * This file provides the only interface to the X server extension support
+ * in programs/Xserver/Xext.  Those programs should only include dmxext.h
+ */
+
+#ifdef HAVE_DMX_CONFIG_H
+#include <dmx-config.h>
+#endif
+
+#include "dmx.h"
+#include "dmxinit.h"
+#include "dmxextension.h"
+#include "dmxwindow.h"
+#include "dmxcb.h"
+#include "dmxcursor.h"
+#include "dmxpixmap.h"
+#include "dmxgc.h"
+#include "dmxfont.h"
+#include "dmxcmap.h"
+#ifdef RENDER
+#include "dmxpict.h"
+#endif
+#include "dmxinput.h"
+#include "dmxsync.h"
+#include "dmxscrinit.h"
+#include "input/dmxinputinit.h"
+
+#include "windowstr.h"
+#include "inputstr.h"                 /* For DeviceIntRec */
+#include <X11/extensions/dmxproto.h>  /* For DMX_BAD_* */
+#include "cursorstr.h"
+
+/* The default font is declared in dix/globals.c, but is not included in
+ * _any_ header files. */
+extern FontPtr  defaultFont;
+    
+/** This routine provides information to the DMX protocol extension
+ * about a particular screen. */
+Bool dmxGetScreenAttributes(int physical, DMXScreenAttributesPtr attr)
+{
+    DMXScreenInfo *dmxScreen;
+
+    if (physical < 0 || physical >= dmxNumScreens) return FALSE;
+
+    dmxScreen = &dmxScreens[physical];
+    attr->displayName         = dmxScreen->name;
+#ifdef PANORAMIX
+    attr->logicalScreen       = noPanoramiXExtension ? dmxScreen->index : 0;
+#else
+    attr->logicalScreen       = dmxScreen->index;
+#endif
+
+    attr->screenWindowWidth   = dmxScreen->scrnWidth;
+    attr->screenWindowHeight  = dmxScreen->scrnHeight;
+    attr->screenWindowXoffset = dmxScreen->scrnX;
+    attr->screenWindowYoffset = dmxScreen->scrnY;
+
+    attr->rootWindowWidth     = dmxScreen->rootWidth;
+    attr->rootWindowHeight    = dmxScreen->rootHeight;
+    attr->rootWindowXoffset   = dmxScreen->rootX;
+    attr->rootWindowYoffset   = dmxScreen->rootY;
+
+    attr->rootWindowXorigin   = dmxScreen->rootXOrigin;
+    attr->rootWindowYorigin   = dmxScreen->rootYOrigin;
+
+    return TRUE;
+}
+
+/** This routine provides information to the DMX protocol extension
+ * about a particular window. */
+Bool dmxGetWindowAttributes(WindowPtr pWindow, DMXWindowAttributesPtr attr)
+{
+    dmxWinPrivPtr pWinPriv = DMX_GET_WINDOW_PRIV(pWindow);
+
+    attr->screen         = pWindow->drawable.pScreen->myNum;
+    attr->window         = pWinPriv->window;
+
+    attr->pos.x          = pWindow->drawable.x;
+    attr->pos.y          = pWindow->drawable.y;
+    attr->pos.width      = pWindow->drawable.width;
+    attr->pos.height     = pWindow->drawable.height;
+
+    if (!pWinPriv->window || pWinPriv->offscreen) {
+        attr->vis.x      = 0;
+        attr->vis.y      = 0;
+        attr->vis.height = 0;
+        attr->vis.width  = 0;
+        return pWinPriv->window ? TRUE : FALSE;
+    }
+
+                                /* Compute display-relative coordinates */
+    attr->vis.x          = pWindow->drawable.x;
+    attr->vis.y          = pWindow->drawable.y;
+    attr->vis.width      = pWindow->drawable.width;
+    attr->vis.height     = pWindow->drawable.height;
+
+    if (attr->pos.x < 0) {
+        attr->vis.x     -= attr->pos.x;
+        attr->vis.width  = attr->pos.x + attr->pos.width - attr->vis.x;
+    }
+    if (attr->pos.x + attr->pos.width > pWindow->drawable.pScreen->width) {
+        if (attr->pos.x < 0)
+            attr->vis.width  = pWindow->drawable.pScreen->width;
+        else
+            attr->vis.width  = pWindow->drawable.pScreen->width - attr->pos.x;
+    }
+    if (attr->pos.y < 0) {
+        attr->vis.y     -= attr->pos.y;
+        attr->vis.height = attr->pos.y + attr->pos.height - attr->vis.y;
+    }
+    if (attr->pos.y + attr->pos.height > pWindow->drawable.pScreen->height) {
+        if (attr->pos.y < 0)
+            attr->vis.height = pWindow->drawable.pScreen->height;
+        else
+            attr->vis.height = pWindow->drawable.pScreen->height - attr->pos.y;
+    }
+
+                                /* Convert to window-relative coordinates */
+    attr->vis.x -= attr->pos.x;
+    attr->vis.y -= attr->pos.y;
+
+    return TRUE;
+}
+
+void dmxGetDesktopAttributes(DMXDesktopAttributesPtr attr)
+{
+    attr->width  = dmxGlobalWidth;
+    attr->height = dmxGlobalHeight;
+    attr->shiftX = 0;            /* NOTE: The upper left hand corner of */
+    attr->shiftY = 0;            /*       the desktop is always <0,0>. */
+}
+
+/** Return the total number of devices, not just #dmxNumInputs.  The
+ * number returned should be the same as that returned by
+ * XListInputDevices. */
+int dmxGetInputCount(void)
+{
+    int i, total;
+    
+    for (total = i = 0; i < dmxNumInputs; i++) total += dmxInputs[i].numDevs;
+    return total;
+}
+
+/** Return information about the device with id = \a deviceId.  This
+ * information is primarily for the #ProcDMXGetInputAttributes()
+ * function, which does not have access to the appropriate data
+ * structure. */
+int dmxGetInputAttributes(int deviceId, DMXInputAttributesPtr attr)
+{
+    int          i, j;
+    DMXInputInfo *dmxInput;
+
+    if (deviceId < 0) return -1;
+    for (i = 0; i < dmxNumInputs; i++) {
+        dmxInput = &dmxInputs[i];
+        for (j = 0; j < dmxInput->numDevs; j++) {
+            DMXLocalInputInfoPtr dmxLocal = dmxInput->devs[j];
+            if (deviceId != dmxLocal->pDevice->id) continue;
+            attr->isCore             = !!dmxLocal->isCore;
+            attr->sendsCore          = !!dmxLocal->sendsCore;
+            attr->detached           = !!dmxInput->detached;
+            attr->physicalScreen     = -1;
+            attr->physicalId         = -1;
+            attr->name               = NULL;
+            switch (dmxLocal->extType) {
+            case DMX_LOCAL_TYPE_LOCAL:
+                attr->inputType      = 0;
+                break;
+            case DMX_LOCAL_TYPE_CONSOLE:
+                attr->inputType      = 1;
+                attr->name           = dmxInput->name;
+                attr->physicalId     = dmxLocal->deviceId;
+                break;
+            case DMX_LOCAL_TYPE_BACKEND:
+            case DMX_LOCAL_TYPE_COMMON:
+                attr->inputType      = 2;
+                attr->physicalScreen = dmxInput->scrnIdx;
+                attr->name           = dmxInput->name;
+                attr->physicalId     = dmxLocal->deviceId;
+                break;
+            }
+            return 0;           /* Success */
+        }
+    }
+    return -1;                  /* Failure */
+}
+
+/** Reinitialized the cursor boundaries. */
+static void dmxAdjustCursorBoundaries(void)
+{
+    int           i;
+
+    dmxReInitOrigins();
+    dmxInitOverlap();
+    dmxComputeWidthHeight(DMX_NO_RECOMPUTE_BOUNDING_BOX);
+    dmxConnectionBlockCallback();
+    for (i = 0; i < dmxNumInputs; i++) {
+        DMXInputInfo *dmxInput = &dmxInputs[i];
+	if (!dmxInput->detached) dmxInputReInit(dmxInput);
+    }
+
+    dmxCheckCursor();
+
+    for (i = 0; i < dmxNumInputs; i++) {
+        DMXInputInfo *dmxInput = &dmxInputs[i];
+	if (!dmxInput->detached) dmxInputLateReInit(dmxInput);
+    }
+}
+
+/** Add an input with the specified attributes.  If the input is added,
+ * the physical id is returned in \a deviceId. */
+int dmxAddInput(DMXInputAttributesPtr attr, int *id)
+{
+    int retcode = BadValue;
+
+    if (attr->inputType == 1)   /* console */
+        retcode = dmxInputAttachConsole(attr->name, attr->sendsCore, id);
+    else if (attr->inputType == 2)   /* backend */
+        retcode = dmxInputAttachBackend(attr->physicalScreen,
+                                        attr->sendsCore,id);
+
+    if (retcode == Success) {
+        /* Adjust the cursor boundaries */
+        dmxAdjustCursorBoundaries();
+
+        /* Force completion of the changes */
+        dmxSync(NULL, TRUE);
+    }
+
+    return retcode;
+}
+
+/** Remove the input with physical id \a id. */
+int dmxRemoveInput(int id)
+{
+    return dmxInputDetachId(id);
+}
+
+/** Return the value of #dmxNumScreens -- the total number of backend
+ * screens in use (these are logical screens and may be larger than the
+ * number of backend displays). */
+unsigned long dmxGetNumScreens(void)
+{
+    return dmxNumScreens;
+}
+
+/** Make sure that #dmxCreateAndRealizeWindow has been called for \a
+ * pWindow. */
+void dmxForceWindowCreation(WindowPtr pWindow)
+{
+    dmxWinPrivPtr pWinPriv = DMX_GET_WINDOW_PRIV(pWindow);
+    if (!pWinPriv->window) dmxCreateAndRealizeWindow(pWindow, TRUE);
+}
+
+/** Flush pending syncs for all screens. */
+void dmxFlushPendingSyncs(void)
+{
+    dmxSync(NULL, TRUE);
+}
+
+/** Update DMX's screen resources to match those of the newly moved
+ *  and/or resized "root" window. */
+void dmxUpdateScreenResources(ScreenPtr pScreen, int x, int y, int w, int h)
+{
+    DMXScreenInfo *dmxScreen = &dmxScreens[pScreen->myNum];
+    WindowPtr      pRoot     = WindowTable[pScreen->myNum];
+    WindowPtr      pChild;
+    Bool           anyMarked = FALSE;
+
+    /* Handle special case where width and/or height are zero */
+    if (w == 0 || h == 0) {
+	w = 1;
+	h = 1;
+    }
+
+    /* Change screen size */
+    pScreen->width  = w;
+    pScreen->height = h;
+
+    /* Reset the root window's drawable's size */
+    pRoot->drawable.width  = w;
+    pRoot->drawable.height = h;
+
+    /* Set the root window's new winSize and borderSize */
+    pRoot->winSize.extents.x1 = 0;
+    pRoot->winSize.extents.y1 = 0;
+    pRoot->winSize.extents.x2 = w;
+    pRoot->winSize.extents.y2 = h;
+
+    pRoot->borderSize.extents.x1 = 0;
+    pRoot->borderSize.extents.y1 = 0;
+    pRoot->borderSize.extents.x2 = w;
+    pRoot->borderSize.extents.y2 = h;
+
+    /* Recompute this screen's mmWidth & mmHeight */
+    pScreen->mmWidth =
+	(w * 254 + dmxScreen->beXDPI * 5) / (dmxScreen->beXDPI * 10);
+    pScreen->mmHeight =
+	(h * 254 + dmxScreen->beYDPI * 5) / (dmxScreen->beYDPI * 10);
+
+    /* Recompute this screen's window's clip rects as follows: */
+    /*   1. Mark all of root's children's windows */
+    for (pChild = pRoot->firstChild; pChild; pChild = pChild->nextSib)
+	anyMarked |= pScreen->MarkOverlappedWindows(pChild, pChild,
+						    (WindowPtr *)NULL);
+
+    /*   2. Set the root window's borderClip */
+    pRoot->borderClip.extents.x1 = 0;
+    pRoot->borderClip.extents.y1 = 0;
+    pRoot->borderClip.extents.x2 = w;
+    pRoot->borderClip.extents.y2 = h;
+
+    /*   3. Set the root window's clipList */
+    if (anyMarked) {
+	/* If any windows have been marked, set the root window's
+	 * clipList to be broken since it will be recalculated in
+	 * ValidateTree()
+	 */
+	REGION_BREAK(pScreen, &pRoot->clipList);
+    } else {
+	/* Otherwise, we just set it directly since there are no
+	 * windows visible on this screen
+	 */
+	pRoot->clipList.extents.x1 = 0;
+	pRoot->clipList.extents.y1 = 0;
+	pRoot->clipList.extents.x2 = w;
+	pRoot->clipList.extents.y2 = h;
+    }
+
+    /*   4. Revalidate all clip rects and generate expose events */
+    if (anyMarked) {
+	pScreen->ValidateTree(pRoot, NULL, VTBroken);
+	pScreen->HandleExposures(pRoot);
+	if (pScreen->PostValidateTree)
+	    pScreen->PostValidateTree(pRoot, NULL, VTBroken);
+    }
+}
+
+#ifdef PANORAMIX
+#include "panoramiXsrv.h"
+
+/* Defined in dix/events.c */
+extern void ReinitializeRootWindow(WindowPtr win, int xoff, int yoff);
+
+/** Change the "screen" window attributes by resizing the actual window
+ *  on the back-end display (if necessary). */
+static void dmxConfigureScreenWindow(int idx,
+				     int x, int y, int w, int h)
+{
+    DMXScreenInfo *dmxScreen = &dmxScreens[idx];
+    ScreenPtr      pScreen   = screenInfo.screens[idx];
+
+    /* Resize "screen" window */
+    if (dmxScreen->scrnX      != x ||
+	dmxScreen->scrnY      != y ||
+	dmxScreen->scrnWidth  != w ||
+	dmxScreen->scrnHeight != h) {
+	dmxResizeScreenWindow(pScreen, x, y, w, h);
+    }
+
+    /* Change "screen" window values */
+    dmxScreen->scrnX      = x;
+    dmxScreen->scrnY      = y;
+    dmxScreen->scrnWidth  = w;
+    dmxScreen->scrnHeight = h;
+}
+				     
+/** Change the "root" window position and size by resizing the actual
+ *  window on the back-end display (if necessary) and updating all of
+ *  DMX's resources by calling #dmxUpdateScreenResources. */
+static void dmxConfigureRootWindow(int idx, int x, int y, int w, int h)
+{
+    DMXScreenInfo *dmxScreen = &dmxScreens[idx];
+    WindowPtr      pRoot     = WindowTable[idx];
+
+    /* NOTE: Either this function or the ones that it calls must handle
+     * the case where w == 0 || h == 0.  Currently, the functions that
+     * this one calls handle that case. */
+
+    /* 1. Resize "root" window */
+    if (dmxScreen->rootX      != x ||
+	dmxScreen->rootY      != y ||
+	dmxScreen->rootWidth  != w ||
+	dmxScreen->rootHeight != h) {
+	dmxResizeRootWindow(pRoot, x, y, w, h);
+    }
+
+    /* 2. Update all of the screen's resources associated with this root
+     *    window */
+    if (dmxScreen->rootWidth  != w ||
+	dmxScreen->rootHeight != h) {
+	dmxUpdateScreenResources(screenInfo.screens[idx], x, y, w, h);
+    }
+
+    /* Change "root" window values */
+    dmxScreen->rootX      = x;
+    dmxScreen->rootY      = y;
+    dmxScreen->rootWidth  = w;
+    dmxScreen->rootHeight = h;
+}
+
+/** Change the "root" window's origin by updating DMX's internal data
+ *  structures (dix and Xinerama) to use the new origin and adjust the
+ *  positions of windows that overlap this "root" window. */
+static void dmxSetRootWindowOrigin(int idx, int x, int y)
+{
+    DMXScreenInfo *dmxScreen = &dmxScreens[idx];
+    ScreenPtr      pScreen   = screenInfo.screens[idx];
+    WindowPtr      pRoot     = WindowTable[idx];
+    WindowPtr      pChild;
+    int            xoff;
+    int            yoff;
+
+    /* Change "root" window's origin */
+    dmxScreen->rootXOrigin = x;
+    dmxScreen->rootYOrigin = y;
+
+    /* Compute offsets here in case <x,y> has been changed above */
+    xoff = x - dixScreenOrigins[idx].x;
+    yoff = y - dixScreenOrigins[idx].y;
+
+    /* Adjust the root window's position in dixScreenOrigins */
+    dixScreenOrigins[idx].x = dmxScreen->rootXOrigin;
+    dixScreenOrigins[idx].y = dmxScreen->rootYOrigin;
+
+    /* Recalculate the Xinerama regions and data structs */
+    XineramaReinitData(pScreen);
+
+    /* Adjust each of the root window's children */
+    if (!idx) ReinitializeRootWindow(WindowTable[0], xoff, yoff);
+    pChild = pRoot->firstChild;
+    while (pChild) {
+	/* Adjust child window's position */
+	pScreen->MoveWindow(pChild,
+			    pChild->origin.x - wBorderWidth(pChild) - xoff,
+			    pChild->origin.y - wBorderWidth(pChild) - yoff,
+			    pChild->nextSib,
+			    VTMove);
+
+	/* Note that the call to MoveWindow will eventually call
+	 * dmxPositionWindow which will automatically create a
+	 * window if it is now exposed on screen (for lazy window
+	 * creation optimization) and it will properly set the
+	 * offscreen flag.
+	 */
+
+	pChild = pChild->nextSib;
+    }
+}
+
+/** Configure the attributes of each "screen" and "root" window. */
+int dmxConfigureScreenWindows(int nscreens,
+			      CARD32 *screens,
+			      DMXScreenAttributesPtr attribs,
+			      int *errorScreen)
+{
+    int           i;
+
+    for (i = 0; i < nscreens; i++) {
+	DMXScreenAttributesPtr  attr      = &attribs[i];
+	int                     idx       = screens[i];
+	DMXScreenInfo          *dmxScreen = &dmxScreens[idx];
+
+	if (errorScreen) *errorScreen = i;
+
+	if (!dmxScreen->beDisplay) return DMX_BAD_VALUE;
+
+	/* Check for illegal values */
+	if (idx < 0 || idx >= dmxNumScreens) return BadValue;
+
+	/* The "screen" and "root" windows must have valid sizes */
+	if (attr->screenWindowWidth <= 0 || attr->screenWindowHeight <= 0 ||
+	    attr->rootWindowWidth   <  0 || attr->rootWindowHeight   <  0)
+	    return DMX_BAD_VALUE;
+
+	/* The "screen" window must fit entirely within the BE display */
+	if (attr->screenWindowXoffset < 0 ||
+	    attr->screenWindowYoffset < 0 ||
+	    attr->screenWindowXoffset
+	    + attr->screenWindowWidth  > (unsigned)dmxScreen->beWidth ||
+	    attr->screenWindowYoffset
+	    + attr->screenWindowHeight > (unsigned)dmxScreen->beHeight)
+	    return DMX_BAD_VALUE;
+
+	/* The "root" window must fit entirely within the "screen" window */
+	if (attr->rootWindowXoffset < 0 ||
+	    attr->rootWindowYoffset < 0 ||
+	    attr->rootWindowXoffset
+	    + attr->rootWindowWidth  > attr->screenWindowWidth ||
+	    attr->rootWindowYoffset
+	    + attr->rootWindowHeight > attr->screenWindowHeight)
+	    return DMX_BAD_VALUE;
+
+	/* The "root" window must not expose unaddressable coordinates */
+	if (attr->rootWindowXorigin < 0 ||
+	    attr->rootWindowYorigin < 0 ||
+	    attr->rootWindowXorigin + attr->rootWindowWidth  > 32767 ||
+	    attr->rootWindowYorigin + attr->rootWindowHeight > 32767)
+	    return DMX_BAD_VALUE;
+
+	/* The "root" window must fit within the global bounding box */
+	if (attr->rootWindowXorigin
+	    + attr->rootWindowWidth > (unsigned)dmxGlobalWidth ||
+	    attr->rootWindowYorigin
+	    + attr->rootWindowHeight > (unsigned)dmxGlobalHeight)
+	    return DMX_BAD_VALUE;
+
+	/* FIXME: Handle the rest of the illegal value checking */
+    }
+
+    /* No illegal values found */
+    if (errorScreen) *errorScreen = 0;
+
+    for (i = 0; i < nscreens; i++) {
+	DMXScreenAttributesPtr  attr      = &attribs[i];
+	int                     idx       = screens[i];
+	DMXScreenInfo          *dmxScreen = &dmxScreens[idx];
+
+	dmxLog(dmxInfo, "Changing screen #%d attributes "
+	       "from %dx%d+%d+%d %dx%d+%d+%d +%d+%d "
+	       "to %dx%d+%d+%d %dx%d+%d+%d +%d+%d\n",
+	       idx,
+	       dmxScreen->scrnWidth,      dmxScreen->scrnHeight,
+	       dmxScreen->scrnX,          dmxScreen->scrnY,
+	       dmxScreen->rootWidth,      dmxScreen->rootHeight,
+	       dmxScreen->rootX,          dmxScreen->rootY,
+	       dmxScreen->rootXOrigin,    dmxScreen->rootYOrigin,
+	       attr->screenWindowWidth,   attr->screenWindowHeight,
+	       attr->screenWindowXoffset, attr->screenWindowYoffset,
+	       attr->rootWindowWidth,     attr->rootWindowHeight,
+	       attr->rootWindowXoffset,   attr->rootWindowYoffset,
+	       attr->rootWindowXorigin,   attr->rootWindowYorigin);
+
+	/* Configure "screen" window */
+	dmxConfigureScreenWindow(idx,
+				 attr->screenWindowXoffset,
+				 attr->screenWindowYoffset,
+				 attr->screenWindowWidth,
+				 attr->screenWindowHeight);
+
+	/* Configure "root" window */
+	dmxConfigureRootWindow(idx,
+			       attr->rootWindowXoffset,
+			       attr->rootWindowYoffset,
+			       attr->rootWindowWidth,
+			       attr->rootWindowHeight);
+
+
+	/* Set "root" window's origin */
+	dmxSetRootWindowOrigin(idx,
+			       attr->rootWindowXorigin,
+			       attr->rootWindowYorigin);
+    }
+
+    /* Adjust the cursor boundaries */
+    dmxAdjustCursorBoundaries();
+
+    /* Force completion of the changes */
+    dmxSync(NULL, TRUE);
+
+    return Success;
+}
+
+/** Configure the attributes of the global desktop. */
+int dmxConfigureDesktop(DMXDesktopAttributesPtr attribs)
+{
+    if (attribs->width  <= 0 || attribs->width  >= 32767 ||
+	attribs->height <= 0 || attribs->height >= 32767)
+	return DMX_BAD_VALUE;
+
+    /* If the desktop is shrinking, adjust the "root" windows on each
+     * "screen" window to only show the visible desktop.  Also, handle
+     * the special case where the desktop shrinks such that the it no
+     * longer overlaps an portion of a "screen" window. */
+    if (attribs->width < dmxGlobalWidth || attribs->height < dmxGlobalHeight) {
+	int   i;
+	for (i = 0; i < dmxNumScreens; i++) {
+	    DMXScreenInfo *dmxScreen = &dmxScreens[i];
+	    if (dmxScreen->rootXOrigin
+		+ dmxScreen->rootWidth  > attribs->width ||
+		dmxScreen->rootYOrigin
+		+ dmxScreen->rootHeight > attribs->height) {
+		int  w, h;
+		if ((w = attribs->width  - dmxScreen->rootXOrigin) < 0) w = 0;
+		if ((h = attribs->height - dmxScreen->rootYOrigin) < 0) h = 0;
+		if (w > dmxScreen->scrnWidth)  w = dmxScreen->scrnWidth;
+		if (h > dmxScreen->scrnHeight) h = dmxScreen->scrnHeight;
+		if (w > dmxScreen->rootWidth)  w = dmxScreen->rootWidth;
+		if (h > dmxScreen->rootHeight) h = dmxScreen->rootHeight;
+		dmxConfigureRootWindow(i,
+				       dmxScreen->rootX,
+				       dmxScreen->rootY,
+				       w, h);
+	    }
+	}
+    }
+
+    /* Set the global width/height */
+    dmxSetWidthHeight(attribs->width, attribs->height);
+
+    /* Handle shift[XY] changes */
+    if (attribs->shiftX || attribs->shiftY) {
+	int   i;
+	for (i = 0; i < dmxNumScreens; i++) {
+	    ScreenPtr  pScreen = screenInfo.screens[i];
+	    WindowPtr  pChild  = WindowTable[i]->firstChild;
+	    while (pChild) {
+		/* Adjust child window's position */
+		pScreen->MoveWindow(pChild,
+				    pChild->origin.x - wBorderWidth(pChild)
+				    - attribs->shiftX,
+				    pChild->origin.y - wBorderWidth(pChild)
+				    - attribs->shiftY,
+				    pChild->nextSib,
+				    VTMove);
+
+		/* Note that the call to MoveWindow will eventually call
+		 * dmxPositionWindow which will automatically create a
+		 * window if it is now exposed on screen (for lazy
+		 * window creation optimization) and it will properly
+		 * set the offscreen flag.
+		 */
+
+		pChild = pChild->nextSib;
+	    }
+	}
+    }
+
+    /* Update connection block, Xinerama, etc. -- these appears to
+     * already be handled in dmxConnectionBlockCallback(), which is
+     * called from dmxAdjustCursorBoundaries() [below]. */
+
+    /* Adjust the cursor boundaries */
+    dmxAdjustCursorBoundaries();
+
+    /* Force completion of the changes */
+    dmxSync(NULL, TRUE);
+
+    return Success;
+}
+#endif
+
+/** Create the scratch GCs per depth. */
+static void dmxBECreateScratchGCs(int scrnNum)
+{
+    ScreenPtr  pScreen = screenInfo.screens[scrnNum];
+    GCPtr     *ppGC    = pScreen->GCperDepth;
+    int        i;
+
+    for (i = 0; i <= pScreen->numDepths; i++)
+	dmxBECreateGC(pScreen, ppGC[i]);
+}
+
+#ifdef PANORAMIX
+static Bool FoundPixImage;
+
+/** Search the Xinerama XRT_PIXMAP resources for the pixmap that needs
+ *  to have its image restored.  When it is found, see if there is
+ *  another screen with the same image.  If so, copy the pixmap image
+ *  from the existing screen to the newly created pixmap. */
+static void dmxBERestorePixmapImage(pointer value, XID id, RESTYPE type,
+				    pointer p)
+{
+    if ((type & TypeMask) == (XRT_PIXMAP & TypeMask)) {
+	PixmapPtr      pDst     = (PixmapPtr)p;
+	int            idx      = pDst->drawable.pScreen->myNum;
+	PanoramiXRes  *pXinPix  = (PanoramiXRes *)value;
+	PixmapPtr      pPix;
+	int            i;
+
+	pPix = (PixmapPtr)LookupIDByType(pXinPix->info[idx].id, RT_PIXMAP);
+	if (pPix != pDst) return; /* Not a match.... Next! */
+
+	for (i = 0; i < PanoramiXNumScreens; i++) {
+	    PixmapPtr      pSrc;
+	    dmxPixPrivPtr  pSrcPriv = NULL;
+
+	    if (i == idx) continue; /* Self replication is bad */
+
+	    pSrc =
+		(PixmapPtr)LookupIDByType(pXinPix->info[i].id, RT_PIXMAP);
+	    pSrcPriv = DMX_GET_PIXMAP_PRIV(pSrc);
+	    if (pSrcPriv->pixmap) {
+		DMXScreenInfo *dmxSrcScreen = &dmxScreens[i];
+		DMXScreenInfo *dmxDstScreen = &dmxScreens[idx];
+		dmxPixPrivPtr  pDstPriv = DMX_GET_PIXMAP_PRIV(pDst);
+		XImage        *img;
+		int            j;
+		XlibGC         gc = NULL;
+
+		/* This should never happen, but just in case.... */
+		if (pSrc->drawable.width  != pDst->drawable.width ||
+		    pSrc->drawable.height != pDst->drawable.height)
+		    return;
+
+		/* Copy from src pixmap to dst pixmap */
+		img = XGetImage(dmxSrcScreen->beDisplay,
+				pSrcPriv->pixmap,
+				0, 0,
+				pSrc->drawable.width, pSrc->drawable.height,
+				-1,
+				ZPixmap);
+
+		for (j = 0; j < dmxDstScreen->beNumPixmapFormats; j++) {
+		    if (dmxDstScreen->bePixmapFormats[j].depth == img->depth) {
+			unsigned long  m;
+			XGCValues      v;
+
+			m = GCFunction | GCPlaneMask | GCClipMask;
+			v.function = GXcopy;
+			v.plane_mask = AllPlanes;
+			v.clip_mask = None;
+
+			gc = XCreateGC(dmxDstScreen->beDisplay,
+				       dmxDstScreen->scrnDefDrawables[j],
+				       m, &v);
+			break;
+		    }
+		}
+
+		if (gc) {
+		    XPutImage(dmxDstScreen->beDisplay,
+			      pDstPriv->pixmap,
+			      gc, img, 0, 0, 0, 0,
+			      pDst->drawable.width, pDst->drawable.height);
+		    XFreeGC(dmxDstScreen->beDisplay, gc);
+		    FoundPixImage = True;
+		} else {
+		    dmxLog(dmxWarning, "Could not create GC\n");
+		}
+
+		XDestroyImage(img);
+		return;
+	    }
+	}
+    }
+}
+#endif
+
+/** Restore the pixmap image either from another screen or from an image
+ *  that was saved when the screen was previously detached. */
+static void dmxBERestorePixmap(PixmapPtr pPixmap)
+{
+#ifdef PANORAMIX
+    int i;
+
+    /* If Xinerama is not active, there's nothing we can do (see comment
+     * in #else below for more info). */
+    if (noPanoramiXExtension) {
+	dmxLog(dmxWarning, "Cannot restore pixmap image\n");
+	return;
+    }
+
+    FoundPixImage = False;
+    for (i = currentMaxClients; --i >= 0; )
+	if (clients[i])
+	    FindAllClientResources(clients[i], dmxBERestorePixmapImage,
+				   (pointer)pPixmap);
+
+    /* No corresponding pixmap image was found on other screens, so we
+     * need to copy it from the saved image when the screen was detached
+     * (if available). */
+    if (!FoundPixImage) {
+	dmxPixPrivPtr  pPixPriv = DMX_GET_PIXMAP_PRIV(pPixmap);
+
+	if (pPixPriv->detachedImage) {
+	    ScreenPtr      pScreen   = pPixmap->drawable.pScreen;
+	    DMXScreenInfo *dmxScreen = &dmxScreens[pScreen->myNum];
+	    XlibGC         gc        = NULL;
+
+	    for (i = 0; i < dmxScreen->beNumPixmapFormats; i++) {
+		if (dmxScreen->bePixmapFormats[i].depth ==
+		    pPixPriv->detachedImage->depth) {
+		    unsigned long  m;
+		    XGCValues      v;
+
+		    m = GCFunction | GCPlaneMask | GCClipMask;
+		    v.function = GXcopy;
+		    v.plane_mask = AllPlanes;
+		    v.clip_mask = None;
+
+		    gc = XCreateGC(dmxScreen->beDisplay,
+				   dmxScreen->scrnDefDrawables[i],
+				   m, &v);
+		    break;
+		}
+	    }
+
+	    if (gc) {
+		XPutImage(dmxScreen->beDisplay,
+			  pPixPriv->pixmap,
+			  gc,
+			  pPixPriv->detachedImage,
+			  0, 0, 0, 0,
+		      pPixmap->drawable.width, pPixmap->drawable.height);
+		XFreeGC(dmxScreen->beDisplay, gc);
+	    } else {
+		dmxLog(dmxWarning, "Cannot restore pixmap image\n");
+	    }
+
+	    XDestroyImage(pPixPriv->detachedImage);
+	    pPixPriv->detachedImage = NULL;
+	} else {
+	    dmxLog(dmxWarning, "Cannot restore pixmap image\n");
+	}
+    }
+#else
+    /* If Xinerama is not enabled, then there is no other copy of the
+     * pixmap image that we can restore.  Saving all pixmap data is not
+     * a feasible option since there is no mechanism for updating pixmap
+     * data when a screen is detached, which means that the data that
+     * was previously saved would most likely be out of date. */
+    dmxLog(dmxWarning, "Cannot restore pixmap image\n");
+    return;
+#endif
+}
+
+/** Create resources on the back-end server.  This function is called
+ *  from #dmxAttachScreen() via the dix layer's FindAllResources
+ *  function.  It walks all resources, compares them to the screen
+ *  number passed in as \a n and calls the appropriate DMX function to
+ *  create the associated resource on the back-end server. */
+static void dmxBECreateResources(pointer value, XID id, RESTYPE type,
+				 pointer n)
+{
+    int        scrnNum = (int)n;
+    ScreenPtr  pScreen = screenInfo.screens[scrnNum];
+
+    if ((type & TypeMask) == (RT_WINDOW & TypeMask)) {
+	/* Window resources are created below in dmxBECreateWindowTree */
+    } else if ((type & TypeMask) == (RT_PIXMAP & TypeMask)) {
+	PixmapPtr  pPix = value;
+	if (pPix->drawable.pScreen->myNum == scrnNum) {
+	    dmxBECreatePixmap(pPix);
+	    dmxBERestorePixmap(pPix);
+	}
+    } else if ((type & TypeMask) == (RT_GC & TypeMask)) {
+	GCPtr  pGC = value;
+	if (pGC->pScreen->myNum == scrnNum) {
+	    /* Create the GC on the back-end server */
+	    dmxBECreateGC(pScreen, pGC);
+	    /* Create any pixmaps associated with this GC */
+	    if (!pGC->tileIsPixel) {
+		dmxBECreatePixmap(pGC->tile.pixmap);
+		dmxBERestorePixmap(pGC->tile.pixmap);
+	    }
+	    if (pGC->stipple != pScreen->PixmapPerDepth[0]) {
+		dmxBECreatePixmap(pGC->stipple);
+		dmxBERestorePixmap(pGC->stipple);
+	    }
+	    if (pGC->font != defaultFont) {
+		(void)dmxBELoadFont(pScreen, pGC->font);
+	    }
+	    /* Update the GC on the back-end server */
+	    dmxChangeGC(pGC, -1L);
+	}
+    } else if ((type & TypeMask) == (RT_FONT & TypeMask)) {
+	(void)dmxBELoadFont(pScreen, (FontPtr)value);
+    } else if ((type & TypeMask) == (RT_CURSOR & TypeMask)) {
+	dmxBECreateCursor(pScreen, (CursorPtr)value);
+    } else if ((type & TypeMask) == (RT_COLORMAP & TypeMask)) {
+	ColormapPtr  pCmap = value;
+	if (pCmap->pScreen->myNum == scrnNum)
+	    (void)dmxBECreateColormap((ColormapPtr)value);
+#if 0
+#ifdef RENDER
+    /* TODO: Recreate Picture and GlyphSet resources */
+    } else if ((type & TypeMask) == (PictureType & TypeMask)) {
+	/* Picture resources are created when windows are created */
+    } else if ((type & TypeMask) == (GlyphSetType & TypeMask)) {
+	dmxBEFreeGlyphSet(pScreen, (GlyphSetPtr)value);
+#endif
+#endif
+    } else {
+	/* Other resource types??? */
+    }
+}
+
+/** Create window hierachy on back-end server.  The window tree is
+ *  created in a special order (bottom most subwindow first) so that the
+ *  #dmxCreateNonRootWindow() function does not need to recursively call
+ *  itself to create each window's parents.  This is required so that we
+ *  have the opportunity to create each window's border and background
+ *  pixmaps (where appropriate) before the window is created. */
+static void dmxBECreateWindowTree(int idx)
+{
+    DMXScreenInfo *dmxScreen = &dmxScreens[idx];
+    WindowPtr      pRoot     = WindowTable[idx];
+    dmxWinPrivPtr  pWinPriv  = DMX_GET_WINDOW_PRIV(pRoot);
+    WindowPtr      pWin;
+
+    /* Create the pixmaps associated with the root window */
+    if (!pRoot->borderIsPixel) {
+	dmxBECreatePixmap(pRoot->border.pixmap);
+	dmxBERestorePixmap(pRoot->border.pixmap);
+    }
+    if (pRoot->backgroundState == BackgroundPixmap) {
+	dmxBECreatePixmap(pRoot->background.pixmap);
+	dmxBERestorePixmap(pRoot->background.pixmap);
+    }
+
+    /* Create root window first */
+    dmxScreen->rootWin = pWinPriv->window = dmxCreateRootWindow(pRoot);
+    XMapWindow(dmxScreen->beDisplay, dmxScreen->rootWin);
+
+    pWin = pRoot->lastChild;
+    while (pWin) {
+	pWinPriv = DMX_GET_WINDOW_PRIV(pWin);
+
+	/* Create the pixmaps regardless of whether or not the
+	 * window is created or not due to lazy window creation.
+	 */
+	if (!pWin->borderIsPixel) {
+	    dmxBECreatePixmap(pWin->border.pixmap);
+	    dmxBERestorePixmap(pWin->border.pixmap);
+	}
+	if (pWin->backgroundState == BackgroundPixmap) {
+	    dmxBECreatePixmap(pWin->background.pixmap);
+	    dmxBERestorePixmap(pWin->background.pixmap);
+	}
+
+	/* Reset the window attributes */
+	dmxGetDefaultWindowAttributes(pWin,
+				      &pWinPriv->cmap,
+				      &pWinPriv->visual);
+
+	/* Create the window */
+	if (pWinPriv->mapped && !pWinPriv->offscreen)
+	    dmxCreateAndRealizeWindow(pWin, TRUE);
+
+	/* Next, create the bottom-most child */
+	if (pWin->lastChild) {
+	    pWin = pWin->lastChild;
+	    continue;
+	}
+
+	/* If the window has no children, move on to the next higher window */
+	while (!pWin->prevSib && (pWin != pRoot))
+	    pWin = pWin->parent;
+
+	if (pWin->prevSib) {
+	    pWin = pWin->prevSib;
+	    continue;
+	}
+
+	/* When we reach the root window, we are finished */
+	if (pWin == pRoot)
+	    break;
+    }
+}
+
+/* Refresh screen by generating exposure events for all windows */
+static void dmxForceExposures(int idx)
+{
+    ScreenPtr      pScreen   = screenInfo.screens[idx];
+    WindowPtr  pRoot     = WindowTable[idx];
+    Bool       anyMarked = FALSE;
+    WindowPtr  pChild;
+
+    for (pChild = pRoot->firstChild; pChild; pChild = pChild->nextSib)
+	anyMarked |= pScreen->MarkOverlappedWindows(pChild, pChild,
+						    (WindowPtr *)NULL);
+    if (anyMarked) {
+	/* If any windows have been marked, set the root window's
+	 * clipList to be broken since it will be recalculated in
+	 * ValidateTree()
+	 */
+	REGION_BREAK(pScreen, &pRoot->clipList);
+	pScreen->ValidateTree(pRoot, NULL, VTBroken);
+	pScreen->HandleExposures(pRoot);
+	if (pScreen->PostValidateTree)
+	    pScreen->PostValidateTree(pRoot, NULL, VTBroken);
+    }
+}
+
+/** Compare the new and old screens to see if they are compatible. */
+static Bool dmxCompareScreens(DMXScreenInfo *new, DMXScreenInfo *old)
+{
+    int i;
+
+    if (new->beWidth != old->beWidth) return FALSE;
+    if (new->beHeight != old->beHeight) return FALSE;
+    if (new->beDepth != old->beDepth) return FALSE;
+    if (new->beBPP != old->beBPP) return FALSE;
+
+    if (new->beNumDepths != old->beNumDepths) return FALSE;
+    for (i = 0; i < old->beNumDepths; i++)
+	if (new->beDepths[i] != old->beDepths[i]) return FALSE;
+
+    if (new->beNumPixmapFormats != old->beNumPixmapFormats) return FALSE;
+    for (i = 0; i < old->beNumPixmapFormats; i++) {
+	if (new->bePixmapFormats[i].depth !=
+	    old->bePixmapFormats[i].depth) return FALSE;
+	if (new->bePixmapFormats[i].bits_per_pixel !=
+	    old->bePixmapFormats[i].bits_per_pixel) return FALSE;
+	if (new->bePixmapFormats[i].scanline_pad !=
+	    old->bePixmapFormats[i].scanline_pad) return FALSE;
+    }
+
+    if (new->beNumVisuals != old->beNumVisuals) return FALSE;
+    for (i = 0; i < old->beNumVisuals; i++) {
+	if (new->beVisuals[i].visualid !=
+	    old->beVisuals[i].visualid) return FALSE;
+	if (new->beVisuals[i].screen !=
+	    old->beVisuals[i].screen) return FALSE;
+	if (new->beVisuals[i].depth !=
+	    old->beVisuals[i].depth) return FALSE;
+	if (new->beVisuals[i].class !=
+	    old->beVisuals[i].class) return FALSE;
+	if (new->beVisuals[i].red_mask !=
+	    old->beVisuals[i].red_mask) return FALSE;
+	if (new->beVisuals[i].green_mask !=
+	    old->beVisuals[i].green_mask) return FALSE;
+	if (new->beVisuals[i].blue_mask !=
+	    old->beVisuals[i].blue_mask) return FALSE;
+	if (new->beVisuals[i].colormap_size !=
+	    old->beVisuals[i].colormap_size) return FALSE;
+	if (new->beVisuals[i].bits_per_rgb !=
+	    old->beVisuals[i].bits_per_rgb) return FALSE;
+    }
+
+    if (new->beDefVisualIndex != old->beDefVisualIndex) return FALSE;
+
+    return TRUE;
+}
+
+/** Reattach previously detached back-end screen. */
+int dmxAttachScreen(int idx, DMXScreenAttributesPtr attr)
+{
+    ScreenPtr      pScreen   = screenInfo.screens[idx];
+    DMXScreenInfo *dmxScreen = &dmxScreens[idx];
+    CARD32         scrnNum   = idx;
+    DMXScreenInfo  oldDMXScreen;
+    int            i;
+
+    /* Return failure if dynamic addition/removal of screens is disabled */
+    if (!dmxAddRemoveScreens) {
+	dmxLog(dmxWarning,
+	       "Attempting to add a screen, but the AddRemoveScreen\n");
+	dmxLog(dmxWarning,
+	       "extension has not been enabled.  To enable this extension\n");
+	dmxLog(dmxWarning,
+	       "add the \"-addremovescreens\" option either to the command\n");
+	dmxLog(dmxWarning,
+	       "line or in the configuration file.\n");
+	return 1;
+    }
+
+    /* Cannot add a screen that does not exist */
+    if (idx < 0 || idx >= dmxNumScreens) return 1;
+
+    /* Cannot attach to a screen that is already opened */
+    if (dmxScreen->beDisplay) {
+	dmxLog(dmxWarning,
+	       "Attempting to add screen #%d but a screen already exists\n",
+	       idx);
+	return 1;
+    }
+
+    dmxLogOutput(dmxScreen, "Attaching screen #%d\n", idx);
+
+    /* Save old info */
+    oldDMXScreen = *dmxScreen;
+
+    /* Copy the name to the new screen */
+    dmxScreen->name = strdup(attr->displayName);
+
+    /* Open display and get all of the screen info */
+    if (!dmxOpenDisplay(dmxScreen)) {
+	dmxLog(dmxWarning,
+               "dmxOpenDisplay: Unable to open display %s\n",
+               dmxScreen->name);
+
+	/* Restore the old screen */
+	*dmxScreen = oldDMXScreen;
+	return 1;
+    }
+
+    dmxSetErrorHandler(dmxScreen);
+    dmxCheckForWM(dmxScreen);
+    dmxGetScreenAttribs(dmxScreen);
+
+    if (!dmxGetVisualInfo(dmxScreen)) {
+	dmxLog(dmxWarning, "dmxGetVisualInfo: No matching visuals found\n");
+	XFree(dmxScreen->beVisuals);
+	XCloseDisplay(dmxScreen->beDisplay);
+
+	/* Restore the old screen */
+	*dmxScreen = oldDMXScreen;
+	return 1;
+    }
+
+    dmxGetColormaps(dmxScreen);
+    dmxGetPixmapFormats(dmxScreen);
+
+    /* Verify that the screen to be added has the same info as the
+     * previously added screen. */
+    if (!dmxCompareScreens(dmxScreen, &oldDMXScreen)) {
+	dmxLog(dmxWarning,
+	       "New screen data (%s) does not match previously\n",
+	       dmxScreen->name);
+	dmxLog(dmxWarning,
+	       "attached screen data (%s)\n",
+	       oldDMXScreen.name);
+	dmxLog(dmxWarning,
+	       "All data must match in order to attach to screen #%d\n",
+	       idx);
+	XFree(dmxScreen->beVisuals);
+	XFree(dmxScreen->beDepths);
+	XFree(dmxScreen->bePixmapFormats);
+	XCloseDisplay(dmxScreen->beDisplay);
+
+	/* Restore the old screen */
+	*dmxScreen = oldDMXScreen;
+	return 1;
+    }
+
+    /* Initialize the BE screen resources */
+    dmxBEScreenInit(idx, screenInfo.screens[idx]);
+
+    /* TODO: Handle GLX visual initialization.  GLXProxy needs to be
+     * updated to handle dynamic addition/removal of screens. */
+
+    /* Create default stipple */
+    dmxBECreatePixmap(pScreen->PixmapPerDepth[0]);
+    dmxBERestorePixmap(pScreen->PixmapPerDepth[0]);
+
+    /* Create the scratch GCs */
+    dmxBECreateScratchGCs(idx);
+
+    /* Create the default font */
+    (void)dmxBELoadFont(pScreen, defaultFont);
+
+    /* Create all resources that don't depend on windows */
+    for (i = currentMaxClients; --i >= 0; )
+	if (clients[i])
+	    FindAllClientResources(clients[i], dmxBECreateResources,
+				   (pointer)idx);
+
+    /* Create window hierarchy (top down) */
+    dmxBECreateWindowTree(idx);
+
+    /* Refresh screen by generating exposure events for all windows */
+    dmxForceExposures(idx);
+
+    dmxSync(&dmxScreens[idx], TRUE);
+
+    /* We used these to compare the old and new screens.  They are no
+     * longer needed since we have a newly attached screen, so we can
+     * now free the old screen's resources. */
+    XFree(oldDMXScreen.beVisuals);
+    XFree(oldDMXScreen.beDepths);
+    XFree(oldDMXScreen.bePixmapFormats);
+    /* TODO: should oldDMXScreen.name be freed?? */
+
+#ifdef PANORAMIX
+    if (!noPanoramiXExtension)
+	return dmxConfigureScreenWindows(1, &scrnNum, attr, NULL);
+    else
+#endif
+	return 0; /* Success */
+}
+
+/*
+ * Resources that may have state on the BE server and need to be freed:
+ *
+ * RT_NONE
+ * RT_WINDOW
+ * RT_PIXMAP
+ * RT_GC
+ * RT_FONT
+ * RT_CURSOR
+ * RT_COLORMAP
+ * RT_CMAPENTRY
+ * RT_OTHERCLIENT
+ * RT_PASSIVEGRAB
+ * XRT_WINDOW
+ * XRT_PIXMAP
+ * XRT_GC
+ * XRT_COLORMAP
+ * XRT_PICTURE
+ * PictureType
+ * PictFormatType
+ * GlyphSetType
+ * ClientType
+ * EventType
+ * RT_INPUTCLIENT
+ * XETrapType
+ * RTCounter
+ * RTAwait
+ * RTAlarmClient
+ * RT_XKBCLIENT
+ * RTContext
+ * TagResType
+ * StalledResType
+ * RT_APPGROUP
+ * SecurityAuthorizationResType
+ * RTEventClient
+ * __glXContextRes
+ * __glXClientRes
+ * __glXPixmapRes
+ * __glXWindowRes
+ * __glXPbufferRes
+ */
+
+#ifdef PANORAMIX
+/** Search the Xinerama XRT_PIXMAP resources for the pixmap that needs
+ *  to have its image saved. */
+static void dmxBEFindPixmapImage(pointer value, XID id, RESTYPE type,
+				 pointer p)
+{
+    if ((type & TypeMask) == (XRT_PIXMAP & TypeMask)) {
+	PixmapPtr      pDst     = (PixmapPtr)p;
+	int            idx      = pDst->drawable.pScreen->myNum;
+	PanoramiXRes  *pXinPix  = (PanoramiXRes *)value;
+	PixmapPtr      pPix;
+	int            i;
+
+	pPix = (PixmapPtr)LookupIDByType(pXinPix->info[idx].id, RT_PIXMAP);
+	if (pPix != pDst) return; /* Not a match.... Next! */
+
+	for (i = 0; i < PanoramiXNumScreens; i++) {
+	    PixmapPtr      pSrc;
+	    dmxPixPrivPtr  pSrcPriv = NULL;
+
+	    if (i == idx) continue; /* Self replication is bad */
+
+	    pSrc =
+		(PixmapPtr)LookupIDByType(pXinPix->info[i].id, RT_PIXMAP);
+	    pSrcPriv = DMX_GET_PIXMAP_PRIV(pSrc);
+	    if (pSrcPriv->pixmap) {
+		FoundPixImage = True;
+		return;
+	    }
+	}
+    }
+}
+#endif
+
+/** Save the pixmap image only when there is not another screen with
+ *  that pixmap from which the image can be read when the screen is
+ *  reattached.  To do this, we first try to find a pixmap on another
+ *  screen corresponding to the one we are trying to save.  If we find
+ *  one, then we do not need to save the image data since during
+ *  reattachment, the image data can be read from that other pixmap.
+ *  However, if we do not find one, then we need to save the image data.
+ *  The common case for these are for the default stipple and root
+ *  tile. */
+static void dmxBESavePixmap(PixmapPtr pPixmap)
+{
+#ifdef PANORAMIX
+    int i;
+
+    /* If Xinerama is not active, there's nothing we can do (see comment
+     * in #else below for more info). */
+    if (noPanoramiXExtension) return;
+
+    FoundPixImage = False;
+    for (i = currentMaxClients; --i >= 0; )
+	if (clients[i])
+	    FindAllClientResources(clients[i], dmxBEFindPixmapImage,
+				   (pointer)pPixmap);
+
+    /* Save the image only if there is no other screens that have a
+     * pixmap that corresponds to the one we are trying to save. */
+    if (!FoundPixImage) {
+	dmxPixPrivPtr  pPixPriv = DMX_GET_PIXMAP_PRIV(pPixmap);
+
+	if (!pPixPriv->detachedImage) {
+	    ScreenPtr      pScreen   = pPixmap->drawable.pScreen;
+	    DMXScreenInfo *dmxScreen = &dmxScreens[pScreen->myNum];
+
+	    pPixPriv->detachedImage = XGetImage(dmxScreen->beDisplay,
+						pPixPriv->pixmap,
+						0, 0,
+						pPixmap->drawable.width,
+						pPixmap->drawable.height,
+						-1,
+						ZPixmap);
+	    if (!pPixPriv->detachedImage)
+		dmxLog(dmxWarning, "Cannot save pixmap image\n");
+	}
+    }
+#else
+    /* NOTE: The only time there is a pixmap on another screen that
+     * corresponds to the one we are trying to save is when Xinerama is
+     * active.  Otherwise, the pixmap image data is only stored on a
+     * single screen, which means that once it is detached, that data is
+     * lost.  We could save the data here, but then that would require
+     * us to implement the ability for Xdmx to keep the pixmap up to
+     * date while the screen is detached, which is beyond the scope of
+     * the current project. */
+    return;
+#endif
+}
+
+/** Destroy resources on the back-end server.  This function is called
+ *  from #dmxDetachScreen() via the dix layer's FindAllResources
+ *  function.  It walks all resources, compares them to the screen
+ *  number passed in as \a n and calls the appropriate DMX function to
+ *  free the associated resource on the back-end server. */
+static void dmxBEDestroyResources(pointer value, XID id, RESTYPE type,
+				  pointer n)
+{
+    int        scrnNum = (int)n;
+    ScreenPtr  pScreen = screenInfo.screens[scrnNum];
+
+    if ((type & TypeMask) == (RT_WINDOW & TypeMask)) {
+	/* Window resources are destroyed below in dmxBEDestroyWindowTree */
+    } else if ((type & TypeMask) == (RT_PIXMAP & TypeMask)) {
+	PixmapPtr  pPix = value;
+	if (pPix->drawable.pScreen->myNum == scrnNum) {
+	    dmxBESavePixmap(pPix);
+	    dmxBEFreePixmap(pPix);
+	}
+    } else if ((type & TypeMask) == (RT_GC & TypeMask)) {
+	GCPtr  pGC = value;
+	if (pGC->pScreen->myNum == scrnNum)
+	    dmxBEFreeGC(pGC);
+    } else if ((type & TypeMask) == (RT_FONT & TypeMask)) {
+	dmxBEFreeFont(pScreen, (FontPtr)value);
+    } else if ((type & TypeMask) == (RT_CURSOR & TypeMask)) {
+	dmxBEFreeCursor(pScreen, (CursorPtr)value);
+    } else if ((type & TypeMask) == (RT_COLORMAP & TypeMask)) {
+	ColormapPtr  pCmap = value;
+	if (pCmap->pScreen->myNum == scrnNum)
+	    dmxBEFreeColormap((ColormapPtr)value);
+#ifdef RENDER
+    } else if ((type & TypeMask) == (PictureType & TypeMask)) {
+	PicturePtr  pPict = value;
+	if (pPict->pDrawable->pScreen->myNum == scrnNum)
+	    dmxBEFreePicture((PicturePtr)value);
+    } else if ((type & TypeMask) == (GlyphSetType & TypeMask)) {
+	dmxBEFreeGlyphSet(pScreen, (GlyphSetPtr)value);
+#endif
+    } else {
+	/* Other resource types??? */
+    }
+}
+
+/** Destroy the scratch GCs that are created per depth. */
+static void dmxBEDestroyScratchGCs(int scrnNum)
+{
+    ScreenPtr  pScreen = screenInfo.screens[scrnNum];
+    GCPtr     *ppGC    = pScreen->GCperDepth;
+    int        i;
+
+    for (i = 0; i <= pScreen->numDepths; i++)
+	dmxBEFreeGC(ppGC[i]);
+}
+
+/** Destroy window hierachy on back-end server.  To ensure that all
+ *  XDestroyWindow() calls succeed, they must be performed in a bottom
+ *  up order so that windows are not destroyed before their children.
+ *  XDestroyWindow(), which is called from #dmxBEDestrowWindow(), will
+ *  destroy a window as well as all of it's children. */
+static void dmxBEDestroyWindowTree(int idx)
+{
+    WindowPtr  pWin   = WindowTable[idx];
+    WindowPtr  pChild = pWin;
+
+    while (1) {
+	if (pChild->firstChild) {
+	    pChild = pChild->firstChild;
+	    continue;
+	}
+
+	/* Destroy the window */
+	dmxBEDestroyWindow(pChild);
+
+	/* Make sure we destroy the window's border and background
+	 * pixmaps if they exist */
+	if (!pChild->borderIsPixel) {
+	    dmxBESavePixmap(pChild->border.pixmap);
+	    dmxBEFreePixmap(pChild->border.pixmap);
+	}
+	if (pChild->backgroundState == BackgroundPixmap) {
+	    dmxBESavePixmap(pChild->background.pixmap);
+	    dmxBEFreePixmap(pChild->background.pixmap);
+	}
+
+	while (!pChild->nextSib && (pChild != pWin)) {
+	    pChild = pChild->parent;
+	    dmxBEDestroyWindow(pChild);
+	    if (!pChild->borderIsPixel) {
+		dmxBESavePixmap(pChild->border.pixmap);
+		dmxBEFreePixmap(pChild->border.pixmap);
+	    }
+	    if (pChild->backgroundState == BackgroundPixmap) {
+		dmxBESavePixmap(pChild->background.pixmap);
+		dmxBEFreePixmap(pChild->background.pixmap);
+	    }
+	}
+
+	if (pChild == pWin)
+	    break;
+
+	pChild = pChild->nextSib;
+    }
+}
+
+/** Detach back-end screen. */
+int dmxDetachScreen(int idx)
+{
+    DMXScreenInfo *dmxScreen = &dmxScreens[idx];
+    int            i;
+
+    /* Return failure if dynamic addition/removal of screens is disabled */
+    if (!dmxAddRemoveScreens) {
+	dmxLog(dmxWarning,
+	       "Attempting to remove a screen, but the AddRemoveScreen\n");
+	dmxLog(dmxWarning,
+	       "extension has not been enabled.  To enable this extension\n");
+	dmxLog(dmxWarning,
+	       "add the \"-addremovescreens\" option either to the command\n");
+	dmxLog(dmxWarning,
+	       "line or in the configuration file.\n");
+	return 1;
+    }
+
+    /* Cannot remove a screen that does not exist */
+    if (idx < 0 || idx >= dmxNumScreens) return 1;
+
+    /* Cannot detach from a screen that is not opened */
+    if (!dmxScreen->beDisplay) {
+	dmxLog(dmxWarning,
+	       "Attempting to remove screen #%d but it has not been opened\n",
+	       idx);
+	return 1;
+    }
+
+    dmxLogOutput(dmxScreen, "Detaching screen #%d\n", idx);
+
+    /* Detach input */
+    dmxInputDetachAll(dmxScreen);
+
+    /* Save all relevant state (TODO) */
+
+    /* Free all non-window resources related to this screen */
+    for (i = currentMaxClients; --i >= 0; )
+	if (clients[i])
+	    FindAllClientResources(clients[i], dmxBEDestroyResources,
+				   (pointer)idx);
+
+    /* Free scratch GCs */
+    dmxBEDestroyScratchGCs(idx);
+
+    /* Free window resources related to this screen */
+    dmxBEDestroyWindowTree(idx);
+
+    /* Free default stipple */
+    dmxBESavePixmap(screenInfo.screens[idx]->PixmapPerDepth[0]);
+    dmxBEFreePixmap(screenInfo.screens[idx]->PixmapPerDepth[0]);
+
+    /* Free the remaining screen resources and close the screen */
+    dmxBECloseScreen(screenInfo.screens[idx]);
+
+    /* Adjust the cursor boundaries (paints detached console window) */
+    dmxAdjustCursorBoundaries();
+
+    return 0; /* Success */
+}