/***********************************************************

Copyright 1987, 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.

Copyright 1987 by Digital Equipment Corporation, Maynard, Massachusetts.

                        All Rights Reserved

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 name of Digital 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.

******************************************************************/

#ifdef HAVE_DIX_CONFIG_H
#include <dix-config.h>
#endif

#include <X11/X.h>
#include <X11/Xproto.h>
#include <stdio.h>
#include <string.h>
#include <strings.h>
#include "misc.h"
#include "dix.h"
#include "dixstruct.h"
#include "colormapst.h"
#include "os.h"
#include "scrnintstr.h"
#include "resource.h"
#include "windowstr.h"
#include "privates.h"
#include "xace.h"

typedef int (*ColorCompareProcPtr) (EntryPtr /*pent */ ,
                                    xrgb * /*prgb */ );

static Pixel FindBestPixel(EntryPtr /*pentFirst */ ,
                           int /*size */ ,
                           xrgb * /*prgb */ ,
                           int  /*channel */
    );

static int AllComp(EntryPtr /*pent */ ,
                   xrgb *       /*prgb */
    );

static int RedComp(EntryPtr /*pent */ ,
                   xrgb *       /*prgb */
    );

static int GreenComp(EntryPtr /*pent */ ,
                     xrgb *     /*prgb */
    );

static int BlueComp(EntryPtr /*pent */ ,
                    xrgb *      /*prgb */
    );

static void FreePixels(ColormapPtr /*pmap */ ,
                       int      /*client */
    );

static void CopyFree(int /*channel */ ,
                     int /*client */ ,
                     ColormapPtr /*pmapSrc */ ,
                     ColormapPtr        /*pmapDst */
    );

static void FreeCell(ColormapPtr /*pmap */ ,
                     Pixel /*i */ ,
                     int        /*channel */
    );

static void UpdateColors(ColormapPtr    /*pmap */
    );

static int AllocDirect(int /*client */ ,
                       ColormapPtr /*pmap */ ,
                       int /*c */ ,
                       int /*r */ ,
                       int /*g */ ,
                       int /*b */ ,
                       Bool /*contig */ ,
                       Pixel * /*pixels */ ,
                       Pixel * /*prmask */ ,
                       Pixel * /*pgmask */ ,
                       Pixel *  /*pbmask */
    );

static int AllocPseudo(int /*client */ ,
                       ColormapPtr /*pmap */ ,
                       int /*c */ ,
                       int /*r */ ,
                       Bool /*contig */ ,
                       Pixel * /*pixels */ ,
                       Pixel * /*pmask */ ,
                       Pixel ** /*pppixFirst */
    );

static Bool AllocCP(ColormapPtr /*pmap */ ,
                    EntryPtr /*pentFirst */ ,
                    int /*count */ ,
                    int /*planes */ ,
                    Bool /*contig */ ,
                    Pixel * /*pixels */ ,
                    Pixel *     /*pMask */
    );

static Bool AllocShared(ColormapPtr /*pmap */ ,
                        Pixel * /*ppix */ ,
                        int /*c */ ,
                        int /*r */ ,
                        int /*g */ ,
                        int /*b */ ,
                        Pixel /*rmask */ ,
                        Pixel /*gmask */ ,
                        Pixel /*bmask */ ,
                        Pixel * /*ppixFirst */
    );

static int FreeCo(ColormapPtr /*pmap */ ,
                  int /*client */ ,
                  int /*color */ ,
                  int /*npixIn */ ,
                  Pixel * /*ppixIn */ ,
                  Pixel         /*mask */
    );

static int TellNoMap(WindowPtr /*pwin */ ,
                     Colormap * /*pmid */
    );

static void FindColorInRootCmap(ColormapPtr /* pmap */ ,
                                EntryPtr /* pentFirst */ ,
                                int /* size */ ,
                                xrgb * /* prgb */ ,
                                Pixel * /* pPixel */ ,
                                int /* channel */ ,
                                ColorCompareProcPtr     /* comp */
    );

#define NUMRED(vis) ((vis->redMask >> vis->offsetRed) + 1)
#define NUMGREEN(vis) ((vis->greenMask >> vis->offsetGreen) + 1)
#define NUMBLUE(vis) ((vis->blueMask >> vis->offsetBlue) + 1)
#if COMPOSITE
#define ALPHAMASK(vis)	((vis)->nplanes < 32 ? 0 : \
			 (CARD32) ~((vis)->redMask|(vis)->greenMask|(vis)->blueMask))
#else
#define ALPHAMASK(vis)	0
#endif

#define RGBMASK(vis) (vis->redMask | vis->greenMask | vis->blueMask | ALPHAMASK(vis))

/* GetNextBitsOrBreak(bits, mask, base)  --
 * (Suggestion: First read the macro, then read this explanation.
 *
 * Either generate the next value to OR in to a pixel or break out of this
 * while loop
 *
 * This macro is used when we're trying to generate all 2^n combinations of
 * bits in mask.  What we're doing here is counting in binary, except that
 * the bits we use to count may not be contiguous.  This macro will be
 * called 2^n times, returning a different value in bits each time. Then
 * it will cause us to break out of a surrounding loop. (It will always be
 * called from within a while loop.)
 * On call: mask is the value we want to find all the combinations for
 * base has 1 bit set where the least significant bit of mask is set
 *
 * For example,if mask is 01010, base should be 0010 and we count like this:
 * 00010 (see this isn't so hard),
 *     then we add base to bits and get 0100. (bits & ~mask) is (0100 & 0100) so
 *      we add that to bits getting (0100 + 0100) =
 * 01000 for our next value.
 *      then we add 0010 to get
 * 01010 and we're done (easy as 1, 2, 3)
 */
#define GetNextBitsOrBreak(bits, mask, base)	\
	    if((bits) == (mask)) 		\
		break;		 		\
	    (bits) += (base);		 	\
	    while((bits) & ~(mask))		\
		(bits) += ((bits) & ~(mask));
/* ID of server as client */
#define SERVER_ID	0

typedef struct _colorResource {
    Colormap mid;
    int client;
} colorResource;

/* Invariants:
 * refcnt == 0 means entry is empty
 * refcnt > 0 means entry is useable by many clients, so it can't be changed
 * refcnt == AllocPrivate means entry owned by one client only
 * fShared should only be set if refcnt == AllocPrivate, and only in red map
 */

/**
 * Create and initialize the color map
 *
 * \param mid    resource to use for this colormap
 * \param alloc  1 iff all entries are allocated writable
 */
int
CreateColormap(Colormap mid, ScreenPtr pScreen, VisualPtr pVisual,
               ColormapPtr *ppcmap, int alloc, int client)
{
    int class, size;
    unsigned long sizebytes;
    ColormapPtr pmap;
    EntryPtr pent;
    int i;
    Pixel *ppix, **pptr;

    class = pVisual->class;
    if (!(class & DynamicClass) && (alloc != AllocNone) &&
        (client != SERVER_ID))
        return BadMatch;

    size = pVisual->ColormapEntries;
    sizebytes = (size * sizeof(Entry)) +
        (LimitClients * sizeof(Pixel *)) + (LimitClients * sizeof(int));
    if ((class | DynamicClass) == DirectColor)
        sizebytes *= 3;
    sizebytes += sizeof(ColormapRec);
    if (mid == pScreen->defColormap) {
        pmap = malloc(sizebytes);
        if (!pmap)
            return BadAlloc;
        if (!dixAllocatePrivates(&pmap->devPrivates, PRIVATE_COLORMAP)) {
            free(pmap);
            return BadAlloc;
        }
    }
    else {
        pmap = _dixAllocateObjectWithPrivates(sizebytes, sizebytes,
                                              offsetof(ColormapRec,
                                                       devPrivates),
                                              PRIVATE_COLORMAP);
        if (!pmap)
            return BadAlloc;
    }
    pmap->red = (EntryPtr) ((char *) pmap + sizeof(ColormapRec));
    sizebytes = size * sizeof(Entry);
    pmap->clientPixelsRed = (Pixel **) ((char *) pmap->red + sizebytes);
    pmap->numPixelsRed = (int *) ((char *) pmap->clientPixelsRed +
                                  (LimitClients * sizeof(Pixel *)));
    pmap->mid = mid;
    pmap->flags = 0;            /* start out with all flags clear */
    if (mid == pScreen->defColormap)
        pmap->flags |= IsDefault;
    pmap->pScreen = pScreen;
    pmap->pVisual = pVisual;
    pmap->class = class;
    if ((class | DynamicClass) == DirectColor)
        size = NUMRED(pVisual);
    pmap->freeRed = size;
    memset((char *) pmap->red, 0, (int) sizebytes);
    memset((char *) pmap->numPixelsRed, 0, LimitClients * sizeof(int));
    for (pptr = &pmap->clientPixelsRed[LimitClients];
         --pptr >= pmap->clientPixelsRed;)
        *pptr = (Pixel *) NULL;
    if (alloc == AllocAll) {
        if (class & DynamicClass)
            pmap->flags |= AllAllocated;
        for (pent = &pmap->red[size - 1]; pent >= pmap->red; pent--)
            pent->refcnt = AllocPrivate;
        pmap->freeRed = 0;
        ppix = xallocarray(size, sizeof(Pixel));
        if (!ppix) {
            free(pmap);
            return BadAlloc;
        }
        pmap->clientPixelsRed[client] = ppix;
        for (i = 0; i < size; i++)
            ppix[i] = i;
        pmap->numPixelsRed[client] = size;
    }

    if ((class | DynamicClass) == DirectColor) {
        pmap->freeGreen = NUMGREEN(pVisual);
        pmap->green = (EntryPtr) ((char *) pmap->numPixelsRed +
                                  (LimitClients * sizeof(int)));
        pmap->clientPixelsGreen = (Pixel **) ((char *) pmap->green + sizebytes);
        pmap->numPixelsGreen = (int *) ((char *) pmap->clientPixelsGreen +
                                        (LimitClients * sizeof(Pixel *)));
        pmap->freeBlue = NUMBLUE(pVisual);
        pmap->blue = (EntryPtr) ((char *) pmap->numPixelsGreen +
                                 (LimitClients * sizeof(int)));
        pmap->clientPixelsBlue = (Pixel **) ((char *) pmap->blue + sizebytes);
        pmap->numPixelsBlue = (int *) ((char *) pmap->clientPixelsBlue +
                                       (LimitClients * sizeof(Pixel *)));

        memset((char *) pmap->green, 0, (int) sizebytes);
        memset((char *) pmap->blue, 0, (int) sizebytes);

        memmove((char *) pmap->clientPixelsGreen,
                (char *) pmap->clientPixelsRed, LimitClients * sizeof(Pixel *));
        memmove((char *) pmap->clientPixelsBlue,
                (char *) pmap->clientPixelsRed, LimitClients * sizeof(Pixel *));
        memset((char *) pmap->numPixelsGreen, 0, LimitClients * sizeof(int));
        memset((char *) pmap->numPixelsBlue, 0, LimitClients * sizeof(int));

        /* If every cell is allocated, mark its refcnt */
        if (alloc == AllocAll) {
            size = pmap->freeGreen;
            for (pent = &pmap->green[size - 1]; pent >= pmap->green; pent--)
                pent->refcnt = AllocPrivate;
            pmap->freeGreen = 0;
            ppix = xallocarray(size, sizeof(Pixel));
            if (!ppix) {
                free(pmap->clientPixelsRed[client]);
                free(pmap);
                return BadAlloc;
            }
            pmap->clientPixelsGreen[client] = ppix;
            for (i = 0; i < size; i++)
                ppix[i] = i;
            pmap->numPixelsGreen[client] = size;

            size = pmap->freeBlue;
            for (pent = &pmap->blue[size - 1]; pent >= pmap->blue; pent--)
                pent->refcnt = AllocPrivate;
            pmap->freeBlue = 0;
            ppix = xallocarray(size, sizeof(Pixel));
            if (!ppix) {
                free(pmap->clientPixelsGreen[client]);
                free(pmap->clientPixelsRed[client]);
                free(pmap);
                return BadAlloc;
            }
            pmap->clientPixelsBlue[client] = ppix;
            for (i = 0; i < size; i++)
                ppix[i] = i;
            pmap->numPixelsBlue[client] = size;
        }
    }
    pmap->flags |= BeingCreated;

    if (!AddResource(mid, RT_COLORMAP, (void *) pmap))
        return BadAlloc;

    /*
     * Security creation/labeling check
     */
    i = XaceHook(XACE_RESOURCE_ACCESS, clients[client], mid, RT_COLORMAP,
                 pmap, RT_NONE, NULL, DixCreateAccess);
    if (i != Success) {
        FreeResource(mid, RT_NONE);
        return i;
    }

    /* If the device wants a chance to initialize the colormap in any way,
     * this is it.  In specific, if this is a Static colormap, this is the
     * time to fill in the colormap's values */
    if (!(*pScreen->CreateColormap) (pmap)) {
        FreeResource(mid, RT_NONE);
        return BadAlloc;
    }
    pmap->flags &= ~BeingCreated;
    *ppcmap = pmap;
    return Success;
}

/**
 *
 * \param value  must conform to DeleteType
 */
int
FreeColormap(void *value, XID mid)
{
    int i;
    EntryPtr pent;
    ColormapPtr pmap = (ColormapPtr) value;

    if (CLIENT_ID(mid) != SERVER_ID) {
        (*pmap->pScreen->UninstallColormap) (pmap);
        WalkTree(pmap->pScreen, (VisitWindowProcPtr) TellNoMap, (void *) &mid);
    }

    /* This is the device's chance to undo anything it needs to, especially
     * to free any storage it allocated */
    (*pmap->pScreen->DestroyColormap) (pmap);

    if (pmap->clientPixelsRed) {
        for (i = 0; i < LimitClients; i++)
            free(pmap->clientPixelsRed[i]);
    }

    if ((pmap->class == PseudoColor) || (pmap->class == GrayScale)) {
        for (pent = &pmap->red[pmap->pVisual->ColormapEntries - 1];
             pent >= pmap->red; pent--) {
            if (pent->fShared) {
                if (--pent->co.shco.red->refcnt == 0)
                    free(pent->co.shco.red);
                if (--pent->co.shco.green->refcnt == 0)
                    free(pent->co.shco.green);
                if (--pent->co.shco.blue->refcnt == 0)
                    free(pent->co.shco.blue);
            }
        }
    }
    if ((pmap->class | DynamicClass) == DirectColor) {
        for (i = 0; i < LimitClients; i++) {
            free(pmap->clientPixelsGreen[i]);
            free(pmap->clientPixelsBlue[i]);
        }
    }

    if (pmap->flags & IsDefault) {
        dixFreePrivates(pmap->devPrivates, PRIVATE_COLORMAP);
        free(pmap);
    }
    else
        dixFreeObjectWithPrivates(pmap, PRIVATE_COLORMAP);
    return Success;
}

/* Tell window that pmid has disappeared */
static int
TellNoMap(WindowPtr pwin, Colormap * pmid)
{
    if (wColormap(pwin) == *pmid) {
        /* This should be call to DeliverEvent */
        xEvent xE = {
            .u.colormap.window = pwin->drawable.id,
            .u.colormap.colormap = None,
            .u.colormap.new = TRUE,
            .u.colormap.state = ColormapUninstalled
        };
        xE.u.u.type = ColormapNotify;
#ifdef PANORAMIX
        if (noPanoramiXExtension || !pwin->drawable.pScreen->myNum)
#endif
            DeliverEvents(pwin, &xE, 1, (WindowPtr) NULL);
        if (pwin->optional) {
            pwin->optional->colormap = None;
            CheckWindowOptionalNeed(pwin);
        }
    }

    return WT_WALKCHILDREN;
}

/* Tell window that pmid got uninstalled */
int
TellLostMap(WindowPtr pwin, void *value)
{
    Colormap *pmid = (Colormap *) value;

#ifdef PANORAMIX
    if (!noPanoramiXExtension && pwin->drawable.pScreen->myNum)
        return WT_STOPWALKING;
#endif
    if (wColormap(pwin) == *pmid) {
        /* This should be call to DeliverEvent */
        xEvent xE = {
            .u.colormap.window = pwin->drawable.id,
            .u.colormap.colormap = *pmid,
            .u.colormap.new = FALSE,
            .u.colormap.state = ColormapUninstalled
        };
        xE.u.u.type = ColormapNotify;
        DeliverEvents(pwin, &xE, 1, (WindowPtr) NULL);
    }

    return WT_WALKCHILDREN;
}

/* Tell window that pmid got installed */
int
TellGainedMap(WindowPtr pwin, void *value)
{
    Colormap *pmid = (Colormap *) value;

#ifdef PANORAMIX
    if (!noPanoramiXExtension && pwin->drawable.pScreen->myNum)
        return WT_STOPWALKING;
#endif
    if (wColormap(pwin) == *pmid) {
        /* This should be call to DeliverEvent */
        xEvent xE = {
            .u.colormap.window = pwin->drawable.id,
            .u.colormap.colormap = *pmid,
            .u.colormap.new = FALSE,
            .u.colormap.state = ColormapInstalled
        };
        xE.u.u.type = ColormapNotify;
        DeliverEvents(pwin, &xE, 1, (WindowPtr) NULL);
    }

    return WT_WALKCHILDREN;
}

int
CopyColormapAndFree(Colormap mid, ColormapPtr pSrc, int client)
{
    ColormapPtr pmap = (ColormapPtr) NULL;
    int result, alloc, size;
    Colormap midSrc;
    ScreenPtr pScreen;
    VisualPtr pVisual;

    pScreen = pSrc->pScreen;
    pVisual = pSrc->pVisual;
    midSrc = pSrc->mid;
    alloc = ((pSrc->flags & AllAllocated) && CLIENT_ID(midSrc) == client) ?
        AllocAll : AllocNone;
    size = pVisual->ColormapEntries;

    /* If the create returns non-0, it failed */
    result = CreateColormap(mid, pScreen, pVisual, &pmap, alloc, client);
    if (result != Success)
        return result;
    if (alloc == AllocAll) {
        memmove((char *) pmap->red, (char *) pSrc->red, size * sizeof(Entry));
        if ((pmap->class | DynamicClass) == DirectColor) {
            memmove((char *) pmap->green, (char *) pSrc->green,
                    size * sizeof(Entry));
            memmove((char *) pmap->blue, (char *) pSrc->blue,
                    size * sizeof(Entry));
        }
        pSrc->flags &= ~AllAllocated;
        FreePixels(pSrc, client);
        UpdateColors(pmap);
        return Success;
    }

    CopyFree(REDMAP, client, pSrc, pmap);
    if ((pmap->class | DynamicClass) == DirectColor) {
        CopyFree(GREENMAP, client, pSrc, pmap);
        CopyFree(BLUEMAP, client, pSrc, pmap);
    }
    if (pmap->class & DynamicClass)
        UpdateColors(pmap);
    /* XXX should worry about removing any RT_CMAPENTRY resource */
    return Success;
}

/* Helper routine for freeing large numbers of cells from a map */
static void
CopyFree(int channel, int client, ColormapPtr pmapSrc, ColormapPtr pmapDst)
{
    int z, npix;
    EntryPtr pentSrcFirst, pentDstFirst;
    EntryPtr pentSrc, pentDst;
    Pixel *ppix;
    int nalloc;

    switch (channel) {
    default:         /* so compiler can see that everything gets initialized */
    case REDMAP:
        ppix = (pmapSrc->clientPixelsRed)[client];
        npix = (pmapSrc->numPixelsRed)[client];
        pentSrcFirst = pmapSrc->red;
        pentDstFirst = pmapDst->red;
        break;
    case GREENMAP:
        ppix = (pmapSrc->clientPixelsGreen)[client];
        npix = (pmapSrc->numPixelsGreen)[client];
        pentSrcFirst = pmapSrc->green;
        pentDstFirst = pmapDst->green;
        break;
    case BLUEMAP:
        ppix = (pmapSrc->clientPixelsBlue)[client];
        npix = (pmapSrc->numPixelsBlue)[client];
        pentSrcFirst = pmapSrc->blue;
        pentDstFirst = pmapDst->blue;
        break;
    }
    nalloc = 0;
    if (pmapSrc->class & DynamicClass) {
        for (z = npix; --z >= 0; ppix++) {
            /* Copy entries */
            pentSrc = pentSrcFirst + *ppix;
            pentDst = pentDstFirst + *ppix;
            if (pentDst->refcnt > 0) {
                pentDst->refcnt++;
            }
            else {
                *pentDst = *pentSrc;
                nalloc++;
                if (pentSrc->refcnt > 0)
                    pentDst->refcnt = 1;
                else
                    pentSrc->fShared = FALSE;
            }
            FreeCell(pmapSrc, *ppix, channel);
        }
    }

    /* Note that FreeCell has already fixed pmapSrc->free{Color} */
    switch (channel) {
    case REDMAP:
        pmapDst->freeRed -= nalloc;
        (pmapDst->clientPixelsRed)[client] = (pmapSrc->clientPixelsRed)[client];
        (pmapSrc->clientPixelsRed)[client] = (Pixel *) NULL;
        (pmapDst->numPixelsRed)[client] = (pmapSrc->numPixelsRed)[client];
        (pmapSrc->numPixelsRed)[client] = 0;
        break;
    case GREENMAP:
        pmapDst->freeGreen -= nalloc;
        (pmapDst->clientPixelsGreen)[client] =
            (pmapSrc->clientPixelsGreen)[client];
        (pmapSrc->clientPixelsGreen)[client] = (Pixel *) NULL;
        (pmapDst->numPixelsGreen)[client] = (pmapSrc->numPixelsGreen)[client];
        (pmapSrc->numPixelsGreen)[client] = 0;
        break;
    case BLUEMAP:
        pmapDst->freeBlue -= nalloc;
        pmapDst->clientPixelsBlue[client] = pmapSrc->clientPixelsBlue[client];
        pmapSrc->clientPixelsBlue[client] = (Pixel *) NULL;
        pmapDst->numPixelsBlue[client] = pmapSrc->numPixelsBlue[client];
        pmapSrc->numPixelsBlue[client] = 0;
        break;
    }
}

/* Free the ith entry in a color map.  Must handle freeing of
 * colors allocated through AllocColorPlanes */
static void
FreeCell(ColormapPtr pmap, Pixel i, int channel)
{
    EntryPtr pent;
    int *pCount;

    switch (channel) {
    default:         /* so compiler can see that everything gets initialized */
    case PSEUDOMAP:
    case REDMAP:
        pent = (EntryPtr) &pmap->red[i];
        pCount = &pmap->freeRed;
        break;
    case GREENMAP:
        pent = (EntryPtr) &pmap->green[i];
        pCount = &pmap->freeGreen;
        break;
    case BLUEMAP:
        pent = (EntryPtr) &pmap->blue[i];
        pCount = &pmap->freeBlue;
        break;
    }
    /* If it's not privately allocated and it's not time to free it, just
     * decrement the count */
    if (pent->refcnt > 1)
        pent->refcnt--;
    else {
        /* If the color type is shared, find the sharedcolor. If decremented
         * refcnt is 0, free the shared cell. */
        if (pent->fShared) {
            if (--pent->co.shco.red->refcnt == 0)
                free(pent->co.shco.red);
            if (--pent->co.shco.green->refcnt == 0)
                free(pent->co.shco.green);
            if (--pent->co.shco.blue->refcnt == 0)
                free(pent->co.shco.blue);
            pent->fShared = FALSE;
        }
        pent->refcnt = 0;
        *pCount += 1;
    }
}

static void
UpdateColors(ColormapPtr pmap)
{
    xColorItem *defs;
    xColorItem *pdef;
    EntryPtr pent;
    VisualPtr pVisual;
    int i, n, size;

    pVisual = pmap->pVisual;
    size = pVisual->ColormapEntries;
    defs = xallocarray(size, sizeof(xColorItem));
    if (!defs)
        return;
    n = 0;
    pdef = defs;
    if (pmap->class == DirectColor) {
        for (i = 0; i < size; i++) {
            if (!pmap->red[i].refcnt &&
                !pmap->green[i].refcnt && !pmap->blue[i].refcnt)
                continue;
            pdef->pixel = ((Pixel) i << pVisual->offsetRed) |
                ((Pixel) i << pVisual->offsetGreen) |
                ((Pixel) i << pVisual->offsetBlue);
            pdef->red = pmap->red[i].co.local.red;
            pdef->green = pmap->green[i].co.local.green;
            pdef->blue = pmap->blue[i].co.local.blue;
            pdef->flags = DoRed | DoGreen | DoBlue;
            pdef++;
            n++;
        }
    }
    else {
        for (i = 0, pent = pmap->red; i < size; i++, pent++) {
            if (!pent->refcnt)
                continue;
            pdef->pixel = i;
            if (pent->fShared) {
                pdef->red = pent->co.shco.red->color;
                pdef->green = pent->co.shco.green->color;
                pdef->blue = pent->co.shco.blue->color;
            }
            else {
                pdef->red = pent->co.local.red;
                pdef->green = pent->co.local.green;
                pdef->blue = pent->co.local.blue;
            }
            pdef->flags = DoRed | DoGreen | DoBlue;
            pdef++;
            n++;
        }
    }
    if (n)
        (*pmap->pScreen->StoreColors) (pmap, n, defs);
    free(defs);
}

/* Tries to find a color in pmap that exactly matches the one requested in prgb
 * if it can't it allocates one.
 * Starts looking at pentFirst + *pPixel, so if you want a specific pixel,
 * load *pPixel with that value, otherwise set it to 0
 */
static int
FindColor(ColormapPtr pmap, EntryPtr pentFirst, int size, xrgb * prgb,
          Pixel * pPixel, int channel, int client, ColorCompareProcPtr comp)
{
    EntryPtr pent;
    Bool foundFree;
    Pixel pixel, Free = 0;
    int npix, count, *nump = NULL;
    Pixel **pixp = NULL, *ppix;
    xColorItem def;

    foundFree = FALSE;

    if ((pixel = *pPixel) >= size)
        pixel = 0;
    /* see if there is a match, and also look for a free entry */
    for (pent = pentFirst + pixel, count = size; --count >= 0;) {
        if (pent->refcnt > 0) {
            if ((*comp) (pent, prgb)) {
                if (client >= 0)
                    pent->refcnt++;
                *pPixel = pixel;
                switch (channel) {
                case REDMAP:
                    *pPixel <<= pmap->pVisual->offsetRed;
                case PSEUDOMAP:
                    break;
                case GREENMAP:
                    *pPixel <<= pmap->pVisual->offsetGreen;
                    break;
                case BLUEMAP:
                    *pPixel <<= pmap->pVisual->offsetBlue;
                    break;
                }
                goto gotit;
            }
        }
        else if (!foundFree && pent->refcnt == 0) {
            Free = pixel;
            foundFree = TRUE;
            /* If we're initializing the colormap, then we are looking for
             * the first free cell we can find, not to minimize the number
             * of entries we use.  So don't look any further. */
            if (pmap->flags & BeingCreated)
                break;
        }
        pixel++;
        if (pixel >= size) {
            pent = pentFirst;
            pixel = 0;
        }
        else
            pent++;
    }

    /* If we got here, we didn't find a match.  If we also didn't find
     * a free entry, we're out of luck.  Otherwise, we'll usurp a free
     * entry and fill it in */
    if (!foundFree)
        return BadAlloc;
    pent = pentFirst + Free;
    pent->fShared = FALSE;
    pent->refcnt = (client >= 0) ? 1 : AllocTemporary;

    switch (channel) {
    case PSEUDOMAP:
        pent->co.local.red = prgb->red;
        pent->co.local.green = prgb->green;
        pent->co.local.blue = prgb->blue;
        def.red = prgb->red;
        def.green = prgb->green;
        def.blue = prgb->blue;
        def.flags = (DoRed | DoGreen | DoBlue);
        if (client >= 0)
            pmap->freeRed--;
        def.pixel = Free;
        break;

    case REDMAP:
        pent->co.local.red = prgb->red;
        def.red = prgb->red;
        def.green = pmap->green[0].co.local.green;
        def.blue = pmap->blue[0].co.local.blue;
        def.flags = DoRed;
        if (client >= 0)
            pmap->freeRed--;
        def.pixel = Free << pmap->pVisual->offsetRed;
        break;

    case GREENMAP:
        pent->co.local.green = prgb->green;
        def.red = pmap->red[0].co.local.red;
        def.green = prgb->green;
        def.blue = pmap->blue[0].co.local.blue;
        def.flags = DoGreen;
        if (client >= 0)
            pmap->freeGreen--;
        def.pixel = Free << pmap->pVisual->offsetGreen;
        break;

    case BLUEMAP:
        pent->co.local.blue = prgb->blue;
        def.red = pmap->red[0].co.local.red;
        def.green = pmap->green[0].co.local.green;
        def.blue = prgb->blue;
        def.flags = DoBlue;
        if (client >= 0)
            pmap->freeBlue--;
        def.pixel = Free << pmap->pVisual->offsetBlue;
        break;
    }
    (*pmap->pScreen->StoreColors) (pmap, 1, &def);
    pixel = Free;
    *pPixel = def.pixel;

 gotit:
    if (pmap->flags & BeingCreated || client == -1)
        return Success;
    /* Now remember the pixel, for freeing later */
    switch (channel) {
    case PSEUDOMAP:
    case REDMAP:
        nump = pmap->numPixelsRed;
        pixp = pmap->clientPixelsRed;
        break;

    case GREENMAP:
        nump = pmap->numPixelsGreen;
        pixp = pmap->clientPixelsGreen;
        break;

    case BLUEMAP:
        nump = pmap->numPixelsBlue;
        pixp = pmap->clientPixelsBlue;
        break;
    }
    npix = nump[client];
    ppix = reallocarray(pixp[client], npix + 1, sizeof(Pixel));
    if (!ppix) {
        pent->refcnt--;
        if (!pent->fShared)
            switch (channel) {
            case PSEUDOMAP:
            case REDMAP:
                pmap->freeRed++;
                break;
            case GREENMAP:
                pmap->freeGreen++;
                break;
            case BLUEMAP:
                pmap->freeBlue++;
                break;
            }
        return BadAlloc;
    }
    ppix[npix] = pixel;
    pixp[client] = ppix;
    nump[client]++;

    return Success;
}

/* Get a read-only color from a ColorMap (probably slow for large maps)
 * Returns by changing the value in pred, pgreen, pblue and pPix
 */
int
AllocColor(ColormapPtr pmap,
           unsigned short *pred, unsigned short *pgreen, unsigned short *pblue,
           Pixel * pPix, int client)
{
    Pixel pixR, pixG, pixB;
    int entries;
    xrgb rgb;
    int class;
    VisualPtr pVisual;
    int npix;
    Pixel *ppix;

    pVisual = pmap->pVisual;
    (*pmap->pScreen->ResolveColor) (pred, pgreen, pblue, pVisual);
    rgb.red = *pred;
    rgb.green = *pgreen;
    rgb.blue = *pblue;
    class = pmap->class;
    entries = pVisual->ColormapEntries;

    /* If the colormap is being created, then we want to be able to change
     * the colormap, even if it's a static type. Otherwise, we'd never be
     * able to initialize static colormaps
     */
    if (pmap->flags & BeingCreated)
        class |= DynamicClass;

    /* If this is one of the static storage classes, and we're not initializing
     * it, the best we can do is to find the closest color entry to the
     * requested one and return that.
     */
    switch (class) {
    case StaticColor:
    case StaticGray:
        /* Look up all three components in the same pmap */
        *pPix = pixR = FindBestPixel(pmap->red, entries, &rgb, PSEUDOMAP);
        *pred = pmap->red[pixR].co.local.red;
        *pgreen = pmap->red[pixR].co.local.green;
        *pblue = pmap->red[pixR].co.local.blue;
        npix = pmap->numPixelsRed[client];
        ppix = reallocarray(pmap->clientPixelsRed[client],
                            npix + 1, sizeof(Pixel));
        if (!ppix)
            return BadAlloc;
        ppix[npix] = pixR;
        pmap->clientPixelsRed[client] = ppix;
        pmap->numPixelsRed[client]++;
        break;

    case TrueColor:
        /* Look up each component in its own map, then OR them together */
        pixR = FindBestPixel(pmap->red, NUMRED(pVisual), &rgb, REDMAP);
        pixG = FindBestPixel(pmap->green, NUMGREEN(pVisual), &rgb, GREENMAP);
        pixB = FindBestPixel(pmap->blue, NUMBLUE(pVisual), &rgb, BLUEMAP);
        *pPix = (pixR << pVisual->offsetRed) |
            (pixG << pVisual->offsetGreen) |
            (pixB << pVisual->offsetBlue) | ALPHAMASK(pVisual);

        *pred = pmap->red[pixR].co.local.red;
        *pgreen = pmap->green[pixG].co.local.green;
        *pblue = pmap->blue[pixB].co.local.blue;
        npix = pmap->numPixelsRed[client];
        ppix = reallocarray(pmap->clientPixelsRed[client],
                            npix + 1, sizeof(Pixel));
        if (!ppix)
            return BadAlloc;
        ppix[npix] = pixR;
        pmap->clientPixelsRed[client] = ppix;
        npix = pmap->numPixelsGreen[client];
        ppix = reallocarray(pmap->clientPixelsGreen[client],
                            npix + 1, sizeof(Pixel));
        if (!ppix)
            return BadAlloc;
        ppix[npix] = pixG;
        pmap->clientPixelsGreen[client] = ppix;
        npix = pmap->numPixelsBlue[client];
        ppix = reallocarray(pmap->clientPixelsBlue[client],
                            npix + 1, sizeof(Pixel));
        if (!ppix)
            return BadAlloc;
        ppix[npix] = pixB;
        pmap->clientPixelsBlue[client] = ppix;
        pmap->numPixelsRed[client]++;
        pmap->numPixelsGreen[client]++;
        pmap->numPixelsBlue[client]++;
        break;

    case GrayScale:
    case PseudoColor:
        if (pmap->mid != pmap->pScreen->defColormap &&
            pmap->pVisual->vid == pmap->pScreen->rootVisual) {
            ColormapPtr prootmap;

            dixLookupResourceByType((void **) &prootmap,
                                    pmap->pScreen->defColormap, RT_COLORMAP,
                                    clients[client], DixReadAccess);

            if (pmap->class == prootmap->class)
                FindColorInRootCmap(prootmap, prootmap->red, entries, &rgb,
                                    pPix, PSEUDOMAP, AllComp);
        }
        if (FindColor(pmap, pmap->red, entries, &rgb, pPix, PSEUDOMAP,
                      client, AllComp) != Success)
            return BadAlloc;
        break;

    case DirectColor:
        if (pmap->mid != pmap->pScreen->defColormap &&
            pmap->pVisual->vid == pmap->pScreen->rootVisual) {
            ColormapPtr prootmap;

            dixLookupResourceByType((void **) &prootmap,
                                    pmap->pScreen->defColormap, RT_COLORMAP,
                                    clients[client], DixReadAccess);

            if (pmap->class == prootmap->class) {
                pixR = (*pPix & pVisual->redMask) >> pVisual->offsetRed;
                FindColorInRootCmap(prootmap, prootmap->red, entries, &rgb,
                                    &pixR, REDMAP, RedComp);
                pixG = (*pPix & pVisual->greenMask) >> pVisual->offsetGreen;
                FindColorInRootCmap(prootmap, prootmap->green, entries, &rgb,
                                    &pixG, GREENMAP, GreenComp);
                pixB = (*pPix & pVisual->blueMask) >> pVisual->offsetBlue;
                FindColorInRootCmap(prootmap, prootmap->blue, entries, &rgb,
                                    &pixB, BLUEMAP, BlueComp);
                *pPix = pixR | pixG | pixB;
            }
        }

        pixR = (*pPix & pVisual->redMask) >> pVisual->offsetRed;
        if (FindColor(pmap, pmap->red, NUMRED(pVisual), &rgb, &pixR, REDMAP,
                      client, RedComp) != Success)
            return BadAlloc;
        pixG = (*pPix & pVisual->greenMask) >> pVisual->offsetGreen;
        if (FindColor(pmap, pmap->green, NUMGREEN(pVisual), &rgb, &pixG,
                      GREENMAP, client, GreenComp) != Success) {
            (void) FreeCo(pmap, client, REDMAP, 1, &pixR, (Pixel) 0);
            return BadAlloc;
        }
        pixB = (*pPix & pVisual->blueMask) >> pVisual->offsetBlue;
        if (FindColor(pmap, pmap->blue, NUMBLUE(pVisual), &rgb, &pixB, BLUEMAP,
                      client, BlueComp) != Success) {
            (void) FreeCo(pmap, client, GREENMAP, 1, &pixG, (Pixel) 0);
            (void) FreeCo(pmap, client, REDMAP, 1, &pixR, (Pixel) 0);
            return BadAlloc;
        }
        *pPix = pixR | pixG | pixB | ALPHAMASK(pVisual);

        break;
    }

    /* if this is the client's first pixel in this colormap, tell the
     * resource manager that the client has pixels in this colormap which
     * should be freed when the client dies */
    if ((pmap->numPixelsRed[client] == 1) &&
        (CLIENT_ID(pmap->mid) != client) && !(pmap->flags & BeingCreated)) {
        colorResource *pcr;

        pcr = malloc(sizeof(colorResource));
        if (!pcr) {
            (void) FreeColors(pmap, client, 1, pPix, (Pixel) 0);
            return BadAlloc;
        }
        pcr->mid = pmap->mid;
        pcr->client = client;
        if (!AddResource(FakeClientID(client), RT_CMAPENTRY, (void *) pcr))
            return BadAlloc;
    }
    return Success;
}

/*
 * FakeAllocColor -- fake an AllocColor request by
 * returning a free pixel if available, otherwise returning
 * the closest matching pixel.  This is used by the mi
 * software sprite code to recolor cursors.  A nice side-effect
 * is that this routine will never return failure.
 */

void
FakeAllocColor(ColormapPtr pmap, xColorItem * item)
{
    Pixel pixR, pixG, pixB;
    Pixel temp;
    int entries;
    xrgb rgb;
    int class;
    VisualPtr pVisual;

    pVisual = pmap->pVisual;
    rgb.red = item->red;
    rgb.green = item->green;
    rgb.blue = item->blue;
    (*pmap->pScreen->ResolveColor) (&rgb.red, &rgb.green, &rgb.blue, pVisual);
    class = pmap->class;
    entries = pVisual->ColormapEntries;

    switch (class) {
    case GrayScale:
    case PseudoColor:
        temp = 0;
        item->pixel = 0;
        if (FindColor(pmap, pmap->red, entries, &rgb, &temp, PSEUDOMAP,
                      -1, AllComp) == Success) {
            item->pixel = temp;
            break;
        }
        /* fall through ... */
    case StaticColor:
    case StaticGray:
        item->pixel = FindBestPixel(pmap->red, entries, &rgb, PSEUDOMAP);
        break;

    case DirectColor:
        /* Look up each component in its own map, then OR them together */
        pixR = (item->pixel & pVisual->redMask) >> pVisual->offsetRed;
        pixG = (item->pixel & pVisual->greenMask) >> pVisual->offsetGreen;
        pixB = (item->pixel & pVisual->blueMask) >> pVisual->offsetBlue;
        if (FindColor(pmap, pmap->red, NUMRED(pVisual), &rgb, &pixR, REDMAP,
                      -1, RedComp) != Success)
            pixR = FindBestPixel(pmap->red, NUMRED(pVisual), &rgb, REDMAP)
                << pVisual->offsetRed;
        if (FindColor(pmap, pmap->green, NUMGREEN(pVisual), &rgb, &pixG,
                      GREENMAP, -1, GreenComp) != Success)
            pixG = FindBestPixel(pmap->green, NUMGREEN(pVisual), &rgb,
                                 GREENMAP) << pVisual->offsetGreen;
        if (FindColor(pmap, pmap->blue, NUMBLUE(pVisual), &rgb, &pixB, BLUEMAP,
                      -1, BlueComp) != Success)
            pixB = FindBestPixel(pmap->blue, NUMBLUE(pVisual), &rgb, BLUEMAP)
                << pVisual->offsetBlue;
        item->pixel = pixR | pixG | pixB;
        break;

    case TrueColor:
        /* Look up each component in its own map, then OR them together */
        pixR = FindBestPixel(pmap->red, NUMRED(pVisual), &rgb, REDMAP);
        pixG = FindBestPixel(pmap->green, NUMGREEN(pVisual), &rgb, GREENMAP);
        pixB = FindBestPixel(pmap->blue, NUMBLUE(pVisual), &rgb, BLUEMAP);
        item->pixel = (pixR << pVisual->offsetRed) |
            (pixG << pVisual->offsetGreen) | (pixB << pVisual->offsetBlue);
        break;
    }
}

/* free a pixel value obtained from FakeAllocColor */
void
FakeFreeColor(ColormapPtr pmap, Pixel pixel)
{
    VisualPtr pVisual;
    Pixel pixR, pixG, pixB;

    switch (pmap->class) {
    case GrayScale:
    case PseudoColor:
        if (pmap->red[pixel].refcnt == AllocTemporary)
            pmap->red[pixel].refcnt = 0;
        break;
    case DirectColor:
        pVisual = pmap->pVisual;
        pixR = (pixel & pVisual->redMask) >> pVisual->offsetRed;
        pixG = (pixel & pVisual->greenMask) >> pVisual->offsetGreen;
        pixB = (pixel & pVisual->blueMask) >> pVisual->offsetBlue;
        if (pmap->red[pixR].refcnt == AllocTemporary)
            pmap->red[pixR].refcnt = 0;
        if (pmap->green[pixG].refcnt == AllocTemporary)
            pmap->green[pixG].refcnt = 0;
        if (pmap->blue[pixB].refcnt == AllocTemporary)
            pmap->blue[pixB].refcnt = 0;
        break;
    }
}

typedef unsigned short BigNumUpper;
typedef unsigned long BigNumLower;

#define BIGNUMLOWERBITS	24
#define BIGNUMUPPERBITS	16
#define BIGNUMLOWER (1 << BIGNUMLOWERBITS)
#define BIGNUMUPPER (1 << BIGNUMUPPERBITS)
#define UPPERPART(i)	((i) >> BIGNUMLOWERBITS)
#define LOWERPART(i)	((i) & (BIGNUMLOWER - 1))

typedef struct _bignum {
    BigNumUpper upper;
    BigNumLower lower;
} BigNumRec, *BigNumPtr;

#define BigNumGreater(x,y) (((x)->upper > (y)->upper) ||\
			    ((x)->upper == (y)->upper && (x)->lower > (y)->lower))

#define UnsignedToBigNum(u,r)	(((r)->upper = UPPERPART(u)), \
				 ((r)->lower = LOWERPART(u)))

#define MaxBigNum(r)		(((r)->upper = BIGNUMUPPER-1), \
				 ((r)->lower = BIGNUMLOWER-1))

static void
BigNumAdd(BigNumPtr x, BigNumPtr y, BigNumPtr r)
{
    BigNumLower lower, carry = 0;

    lower = x->lower + y->lower;
    if (lower >= BIGNUMLOWER) {
        lower -= BIGNUMLOWER;
        carry = 1;
    }
    r->lower = lower;
    r->upper = x->upper + y->upper + carry;
}

static Pixel
FindBestPixel(EntryPtr pentFirst, int size, xrgb * prgb, int channel)
{
    EntryPtr pent;
    Pixel pixel, final;
    long dr, dg, db;
    unsigned long sq;
    BigNumRec minval, sum, temp;

    final = 0;
    MaxBigNum(&minval);
    /* look for the minimal difference */
    for (pent = pentFirst, pixel = 0; pixel < size; pent++, pixel++) {
        dr = dg = db = 0;
        switch (channel) {
        case PSEUDOMAP:
            dg = (long) pent->co.local.green - prgb->green;
            db = (long) pent->co.local.blue - prgb->blue;
            /* fallthrough */
        case REDMAP:
            dr = (long) pent->co.local.red - prgb->red;
            break;
        case GREENMAP:
            dg = (long) pent->co.local.green - prgb->green;
            break;
        case BLUEMAP:
            db = (long) pent->co.local.blue - prgb->blue;
            break;
        }
        sq = dr * dr;
        UnsignedToBigNum(sq, &sum);
        sq = dg * dg;
        UnsignedToBigNum(sq, &temp);
        BigNumAdd(&sum, &temp, &sum);
        sq = db * db;
        UnsignedToBigNum(sq, &temp);
        BigNumAdd(&sum, &temp, &sum);
        if (BigNumGreater(&minval, &sum)) {
            final = pixel;
            minval = sum;
        }
    }
    return final;
}

static void
FindColorInRootCmap(ColormapPtr pmap, EntryPtr pentFirst, int size,
                    xrgb * prgb, Pixel * pPixel, int channel,
                    ColorCompareProcPtr comp)
{
    EntryPtr pent;
    Pixel pixel;
    int count;

    if ((pixel = *pPixel) >= size)
        pixel = 0;
    for (pent = pentFirst + pixel, count = size; --count >= 0; pent++, pixel++) {
        if (pent->refcnt > 0 && (*comp) (pent, prgb)) {
            switch (channel) {
            case REDMAP:
                pixel <<= pmap->pVisual->offsetRed;
                break;
            case GREENMAP:
                pixel <<= pmap->pVisual->offsetGreen;
                break;
            case BLUEMAP:
                pixel <<= pmap->pVisual->offsetBlue;
                break;
            default:           /* PSEUDOMAP */
                break;
            }
            *pPixel = pixel;
        }
    }
}

/* Comparison functions -- passed to FindColor to determine if an
 * entry is already the color we're looking for or not */
static int
AllComp(EntryPtr pent, xrgb * prgb)
{
    if ((pent->co.local.red == prgb->red) &&
        (pent->co.local.green == prgb->green) &&
        (pent->co.local.blue == prgb->blue))
        return 1;
    return 0;
}

static int
RedComp(EntryPtr pent, xrgb * prgb)
{
    if (pent->co.local.red == prgb->red)
        return 1;
    return 0;
}

static int
GreenComp(EntryPtr pent, xrgb * prgb)
{
    if (pent->co.local.green == prgb->green)
        return 1;
    return 0;
}

static int
BlueComp(EntryPtr pent, xrgb * prgb)
{
    if (pent->co.local.blue == prgb->blue)
        return 1;
    return 0;
}

/* Read the color value of a cell */

int
QueryColors(ColormapPtr pmap, int count, Pixel * ppixIn, xrgb * prgbList,
            ClientPtr client)
{
    Pixel *ppix, pixel;
    xrgb *prgb;
    VisualPtr pVisual;
    EntryPtr pent;
    Pixel i;
    int errVal = Success;

    pVisual = pmap->pVisual;
    if ((pmap->class | DynamicClass) == DirectColor) {
        int numred, numgreen, numblue;
        Pixel rgbbad;

        numred = NUMRED(pVisual);
        numgreen = NUMGREEN(pVisual);
        numblue = NUMBLUE(pVisual);
        rgbbad = ~RGBMASK(pVisual);
        for (ppix = ppixIn, prgb = prgbList; --count >= 0; ppix++, prgb++) {
            pixel = *ppix;
            if (pixel & rgbbad) {
                client->errorValue = pixel;
                errVal = BadValue;
                continue;
            }
            i = (pixel & pVisual->redMask) >> pVisual->offsetRed;
            if (i >= numred) {
                client->errorValue = pixel;
                errVal = BadValue;
                continue;
            }
            prgb->red = pmap->red[i].co.local.red;
            i = (pixel & pVisual->greenMask) >> pVisual->offsetGreen;
            if (i >= numgreen) {
                client->errorValue = pixel;
                errVal = BadValue;
                continue;
            }
            prgb->green = pmap->green[i].co.local.green;
            i = (pixel & pVisual->blueMask) >> pVisual->offsetBlue;
            if (i >= numblue) {
                client->errorValue = pixel;
                errVal = BadValue;
                continue;
            }
            prgb->blue = pmap->blue[i].co.local.blue;
        }
    }
    else {
        for (ppix = ppixIn, prgb = prgbList; --count >= 0; ppix++, prgb++) {
            pixel = *ppix;
            if (pixel >= pVisual->ColormapEntries) {
                client->errorValue = pixel;
                errVal = BadValue;
            }
            else {
                pent = (EntryPtr) &pmap->red[pixel];
                if (pent->fShared) {
                    prgb->red = pent->co.shco.red->color;
                    prgb->green = pent->co.shco.green->color;
                    prgb->blue = pent->co.shco.blue->color;
                }
                else {
                    prgb->red = pent->co.local.red;
                    prgb->green = pent->co.local.green;
                    prgb->blue = pent->co.local.blue;
                }
            }
        }
    }
    return errVal;
}

static void
FreePixels(ColormapPtr pmap, int client)
{
    Pixel *ppix, *ppixStart;
    int n;
    int class;

    class = pmap->class;
    ppixStart = pmap->clientPixelsRed[client];
    if (class & DynamicClass) {
        n = pmap->numPixelsRed[client];
        for (ppix = ppixStart; --n >= 0;) {
            FreeCell(pmap, *ppix, REDMAP);
            ppix++;
        }
    }

    free(ppixStart);
    pmap->clientPixelsRed[client] = (Pixel *) NULL;
    pmap->numPixelsRed[client] = 0;
    if ((class | DynamicClass) == DirectColor) {
        ppixStart = pmap->clientPixelsGreen[client];
        if (class & DynamicClass)
            for (ppix = ppixStart, n = pmap->numPixelsGreen[client]; --n >= 0;)
                FreeCell(pmap, *ppix++, GREENMAP);
        free(ppixStart);
        pmap->clientPixelsGreen[client] = (Pixel *) NULL;
        pmap->numPixelsGreen[client] = 0;

        ppixStart = pmap->clientPixelsBlue[client];
        if (class & DynamicClass)
            for (ppix = ppixStart, n = pmap->numPixelsBlue[client]; --n >= 0;)
                FreeCell(pmap, *ppix++, BLUEMAP);
        free(ppixStart);
        pmap->clientPixelsBlue[client] = (Pixel *) NULL;
        pmap->numPixelsBlue[client] = 0;
    }
}

/**
 * Frees all of a client's colors and cells.
 *
 *  \param value  must conform to DeleteType
 *  \unused fakeid
 */
int
FreeClientPixels(void *value, XID fakeid)
{
    void *pmap;
    colorResource *pcr = value;
    int rc;

    rc = dixLookupResourceByType(&pmap, pcr->mid, RT_COLORMAP, serverClient,
                                 DixRemoveAccess);
    if (rc == Success)
        FreePixels((ColormapPtr) pmap, pcr->client);
    free(pcr);
    return Success;
}

int
AllocColorCells(int client, ColormapPtr pmap, int colors, int planes,
                Bool contig, Pixel * ppix, Pixel * masks)
{
    Pixel rmask, gmask, bmask, *ppixFirst, r, g, b;
    int n, class;
    int ok;
    int oldcount;
    colorResource *pcr = (colorResource *) NULL;

    class = pmap->class;
    if (!(class & DynamicClass))
        return BadAlloc;        /* Shouldn't try on this type */
    oldcount = pmap->numPixelsRed[client];
    if (pmap->class == DirectColor)
        oldcount += pmap->numPixelsGreen[client] + pmap->numPixelsBlue[client];
    if (!oldcount && (CLIENT_ID(pmap->mid) != client)) {
        pcr = malloc(sizeof(colorResource));
        if (!pcr)
            return BadAlloc;
    }

    if (pmap->class == DirectColor) {
        ok = AllocDirect(client, pmap, colors, planes, planes, planes,
                         contig, ppix, &rmask, &gmask, &bmask);
        if (ok == Success) {
            for (r = g = b = 1, n = planes; --n >= 0; r += r, g += g, b += b) {
                while (!(rmask & r))
                    r += r;
                while (!(gmask & g))
                    g += g;
                while (!(bmask & b))
                    b += b;
                *masks++ = r | g | b;
            }
        }
    }
    else {
        ok = AllocPseudo(client, pmap, colors, planes, contig, ppix, &rmask,
                         &ppixFirst);
        if (ok == Success) {
            for (r = 1, n = planes; --n >= 0; r += r) {
                while (!(rmask & r))
                    r += r;
                *masks++ = r;
            }
        }
    }

    /* if this is the client's first pixels in this colormap, tell the
     * resource manager that the client has pixels in this colormap which
     * should be freed when the client dies */
    if ((ok == Success) && pcr) {
        pcr->mid = pmap->mid;
        pcr->client = client;
        if (!AddResource(FakeClientID(client), RT_CMAPENTRY, (void *) pcr))
            ok = BadAlloc;
    }
    else
        free(pcr);

    return ok;
}

int
AllocColorPlanes(int client, ColormapPtr pmap, int colors,
                 int r, int g, int b, Bool contig, Pixel * pixels,
                 Pixel * prmask, Pixel * pgmask, Pixel * pbmask)
{
    int ok;
    Pixel mask, *ppixFirst;
    Pixel shift;
    int i;
    int class;
    int oldcount;
    colorResource *pcr = (colorResource *) NULL;

    class = pmap->class;
    if (!(class & DynamicClass))
        return BadAlloc;        /* Shouldn't try on this type */
    oldcount = pmap->numPixelsRed[client];
    if (class == DirectColor)
        oldcount += pmap->numPixelsGreen[client] + pmap->numPixelsBlue[client];
    if (!oldcount && (CLIENT_ID(pmap->mid) != client)) {
        pcr = malloc(sizeof(colorResource));
        if (!pcr)
            return BadAlloc;
    }

    if (class == DirectColor) {
        ok = AllocDirect(client, pmap, colors, r, g, b, contig, pixels,
                         prmask, pgmask, pbmask);
    }
    else {
        /* Allocate the proper pixels */
        /* XXX This is sort of bad, because of contig is set, we force all
         * r + g + b bits to be contiguous.  Should only force contiguity
         * per mask
         */
        ok = AllocPseudo(client, pmap, colors, r + g + b, contig, pixels,
                         &mask, &ppixFirst);

        if (ok == Success) {
            /* now split that mask into three */
            *prmask = *pgmask = *pbmask = 0;
            shift = 1;
            for (i = r; --i >= 0; shift += shift) {
                while (!(mask & shift))
                    shift += shift;
                *prmask |= shift;
            }
            for (i = g; --i >= 0; shift += shift) {
                while (!(mask & shift))
                    shift += shift;
                *pgmask |= shift;
            }
            for (i = b; --i >= 0; shift += shift) {
                while (!(mask & shift))
                    shift += shift;
                *pbmask |= shift;
            }

            /* set up the shared color cells */
            if (!AllocShared(pmap, pixels, colors, r, g, b,
                             *prmask, *pgmask, *pbmask, ppixFirst)) {
                (void) FreeColors(pmap, client, colors, pixels, mask);
                ok = BadAlloc;
            }
        }
    }

    /* if this is the client's first pixels in this colormap, tell the
     * resource manager that the client has pixels in this colormap which
     * should be freed when the client dies */
    if ((ok == Success) && pcr) {
        pcr->mid = pmap->mid;
        pcr->client = client;
        if (!AddResource(FakeClientID(client), RT_CMAPENTRY, (void *) pcr))
            ok = BadAlloc;
    }
    else
        free(pcr);

    return ok;
}

static int
AllocDirect(int client, ColormapPtr pmap, int c, int r, int g, int b,
            Bool contig, Pixel * pixels, Pixel * prmask, Pixel * pgmask,
            Pixel * pbmask)
{
    Pixel *ppixRed, *ppixGreen, *ppixBlue;
    Pixel *ppix, *pDst, *p;
    int npix, npixR, npixG, npixB;
    Bool okR, okG, okB;
    Pixel *rpix = 0, *gpix = 0, *bpix = 0;

    npixR = c << r;
    npixG = c << g;
    npixB = c << b;
    if ((r >= 32) || (g >= 32) || (b >= 32) ||
        (npixR > pmap->freeRed) || (npixR < c) ||
        (npixG > pmap->freeGreen) || (npixG < c) ||
        (npixB > pmap->freeBlue) || (npixB < c))
        return BadAlloc;

    /* start out with empty pixels */
    for (p = pixels; p < pixels + c; p++)
        *p = 0;

    ppixRed = xallocarray(npixR, sizeof(Pixel));
    ppixGreen = xallocarray(npixG, sizeof(Pixel));
    ppixBlue = xallocarray(npixB, sizeof(Pixel));
    if (!ppixRed || !ppixGreen || !ppixBlue) {
        free(ppixBlue);
        free(ppixGreen);
        free(ppixRed);
        return BadAlloc;
    }

    okR = AllocCP(pmap, pmap->red, c, r, contig, ppixRed, prmask);
    okG = AllocCP(pmap, pmap->green, c, g, contig, ppixGreen, pgmask);
    okB = AllocCP(pmap, pmap->blue, c, b, contig, ppixBlue, pbmask);

    if (okR && okG && okB) {
        rpix = reallocarray(pmap->clientPixelsRed[client],
                            pmap->numPixelsRed[client] + (c << r),
                            sizeof(Pixel));
        if (rpix)
            pmap->clientPixelsRed[client] = rpix;
        gpix = reallocarray(pmap->clientPixelsGreen[client],
                            pmap->numPixelsGreen[client] + (c << g),
                            sizeof(Pixel));
        if (gpix)
            pmap->clientPixelsGreen[client] = gpix;
        bpix = reallocarray(pmap->clientPixelsBlue[client],
                            pmap->numPixelsBlue[client] + (c << b),
                            sizeof(Pixel));
        if (bpix)
            pmap->clientPixelsBlue[client] = bpix;
    }

    if (!okR || !okG || !okB || !rpix || !gpix || !bpix) {
        if (okR)
            for (ppix = ppixRed, npix = npixR; --npix >= 0; ppix++)
                pmap->red[*ppix].refcnt = 0;
        if (okG)
            for (ppix = ppixGreen, npix = npixG; --npix >= 0; ppix++)
                pmap->green[*ppix].refcnt = 0;
        if (okB)
            for (ppix = ppixBlue, npix = npixB; --npix >= 0; ppix++)
                pmap->blue[*ppix].refcnt = 0;
        free(ppixBlue);
        free(ppixGreen);
        free(ppixRed);
        return BadAlloc;
    }

    *prmask <<= pmap->pVisual->offsetRed;
    *pgmask <<= pmap->pVisual->offsetGreen;
    *pbmask <<= pmap->pVisual->offsetBlue;

    ppix = rpix + pmap->numPixelsRed[client];
    for (pDst = pixels, p = ppixRed; p < ppixRed + npixR; p++) {
        *ppix++ = *p;
        if (p < ppixRed + c)
            *pDst++ |= *p << pmap->pVisual->offsetRed;
    }
    pmap->numPixelsRed[client] += npixR;
    pmap->freeRed -= npixR;

    ppix = gpix + pmap->numPixelsGreen[client];
    for (pDst = pixels, p = ppixGreen; p < ppixGreen + npixG; p++) {
        *ppix++ = *p;
        if (p < ppixGreen + c)
            *pDst++ |= *p << pmap->pVisual->offsetGreen;
    }
    pmap->numPixelsGreen[client] += npixG;
    pmap->freeGreen -= npixG;

    ppix = bpix + pmap->numPixelsBlue[client];
    for (pDst = pixels, p = ppixBlue; p < ppixBlue + npixB; p++) {
        *ppix++ = *p;
        if (p < ppixBlue + c)
            *pDst++ |= *p << pmap->pVisual->offsetBlue;
    }
    pmap->numPixelsBlue[client] += npixB;
    pmap->freeBlue -= npixB;

    for (pDst = pixels; pDst < pixels + c; pDst++)
        *pDst |= ALPHAMASK(pmap->pVisual);

    free(ppixBlue);
    free(ppixGreen);
    free(ppixRed);

    return Success;
}

static int
AllocPseudo(int client, ColormapPtr pmap, int c, int r, Bool contig,
            Pixel * pixels, Pixel * pmask, Pixel ** pppixFirst)
{
    Pixel *ppix, *p, *pDst, *ppixTemp;
    int npix;
    Bool ok;

    npix = c << r;
    if ((r >= 32) || (npix > pmap->freeRed) || (npix < c))
        return BadAlloc;
    if (!(ppixTemp = xallocarray(npix, sizeof(Pixel))))
        return BadAlloc;
    ok = AllocCP(pmap, pmap->red, c, r, contig, ppixTemp, pmask);

    if (ok) {

        /* all the allocated pixels are added to the client pixel list,
         * but only the unique ones are returned to the client */
        ppix = reallocarray(pmap->clientPixelsRed[client],
                            pmap->numPixelsRed[client] + npix, sizeof(Pixel));
        if (!ppix) {
            for (p = ppixTemp; p < ppixTemp + npix; p++)
                pmap->red[*p].refcnt = 0;
            free(ppixTemp);
            return BadAlloc;
        }
        pmap->clientPixelsRed[client] = ppix;
        ppix += pmap->numPixelsRed[client];
        *pppixFirst = ppix;
        pDst = pixels;
        for (p = ppixTemp; p < ppixTemp + npix; p++) {
            *ppix++ = *p;
            if (p < ppixTemp + c)
                *pDst++ = *p;
        }
        pmap->numPixelsRed[client] += npix;
        pmap->freeRed -= npix;
    }
    free(ppixTemp);
    return ok ? Success : BadAlloc;
}

/* Allocates count << planes pixels from colormap pmap for client. If
 * contig, then the plane mask is made of consecutive bits.  Returns
 * all count << pixels in the array pixels. The first count of those
 * pixels are the unique pixels.  *pMask has the mask to Or with the
 * unique pixels to get the rest of them.
 *
 * Returns True iff all pixels could be allocated
 * All cells allocated will have refcnt set to AllocPrivate and shared to FALSE
 * (see AllocShared for why we care)
 */
static Bool
AllocCP(ColormapPtr pmap, EntryPtr pentFirst, int count, int planes,
        Bool contig, Pixel * pixels, Pixel * pMask)
{
    EntryPtr ent;
    Pixel pixel, base, entries, maxp, save;
    int dplanes, found;
    Pixel *ppix;
    Pixel mask;
    Pixel finalmask;

    dplanes = pmap->pVisual->nplanes;

    /* Easy case.  Allocate pixels only */
    if (planes == 0) {
        /* allocate writable entries */
        ppix = pixels;
        ent = pentFirst;
        pixel = 0;
        while (--count >= 0) {
            /* Just find count unallocated cells */
            while (ent->refcnt) {
                ent++;
                pixel++;
            }
            ent->refcnt = AllocPrivate;
            *ppix++ = pixel;
            ent->fShared = FALSE;
        }
        *pMask = 0;
        return TRUE;
    }
    else if (planes > dplanes) {
        return FALSE;
    }

    /* General case count pixels * 2 ^ planes cells to be allocated */

    /* make room for new pixels */
    ent = pentFirst;

    /* first try for contiguous planes, since it's fastest */
    for (mask = (((Pixel) 1) << planes) - 1, base = 1, dplanes -= (planes - 1);
         --dplanes >= 0; mask += mask, base += base) {
        ppix = pixels;
        found = 0;
        pixel = 0;
        entries = pmap->pVisual->ColormapEntries - mask;
        while (pixel < entries) {
            save = pixel;
            maxp = pixel + mask + base;
            /* check if all are free */
            while (pixel != maxp && ent[pixel].refcnt == 0)
                pixel += base;
            if (pixel == maxp) {
                /* this one works */
                *ppix++ = save;
                found++;
                if (found == count) {
                    /* found enough, allocate them all */
                    while (--count >= 0) {
                        pixel = pixels[count];
                        maxp = pixel + mask;
                        while (1) {
                            ent[pixel].refcnt = AllocPrivate;
                            ent[pixel].fShared = FALSE;
                            if (pixel == maxp)
                                break;
                            pixel += base;
                            *ppix++ = pixel;
                        }
                    }
                    *pMask = mask;
                    return TRUE;
                }
            }
            pixel = save + 1;
            if (pixel & mask)
                pixel += mask;
        }
    }

    dplanes = pmap->pVisual->nplanes;
    if (contig || planes == 1 || dplanes < 3)
        return FALSE;

    /* this will be very slow for large maps, need a better algorithm */

    /*
       we can generate the smallest and largest numbers that fits in dplanes
       bits and contain exactly planes bits set as follows. First, we need to
       check that it is possible to generate such a mask at all.
       (Non-contiguous masks need one more bit than contiguous masks). Then
       the smallest such mask consists of the rightmost planes-1 bits set, then
       a zero, then a one in position planes + 1. The formula is
       (3 << (planes-1)) -1
       The largest such masks consists of the leftmost planes-1 bits set, then
       a zero, then a one bit in position dplanes-planes-1. If dplanes is
       smaller than 32 (the number of bits in a word) then the formula is:
       (1<<dplanes) - (1<<(dplanes-planes+1) + (1<<dplanes-planes-1)
       If dplanes = 32, then we can't calculate (1<<dplanes) and we have
       to use:
       ( (1<<(planes-1)) - 1) << (dplanes-planes+1) + (1<<(dplanes-planes-1))

       << Thank you, Loretta>>>

     */

    finalmask =
        (((((Pixel) 1) << (planes - 1)) - 1) << (dplanes - planes + 1)) +
        (((Pixel) 1) << (dplanes - planes - 1));
    for (mask = (((Pixel) 3) << (planes - 1)) - 1; mask <= finalmask; mask++) {
        /* next 3 magic statements count number of ones (HAKMEM #169) */
        pixel = (mask >> 1) & 033333333333;
        pixel = mask - pixel - ((pixel >> 1) & 033333333333);
        if ((((pixel + (pixel >> 3)) & 030707070707) % 077) != planes)
            continue;
        ppix = pixels;
        found = 0;
        entries = pmap->pVisual->ColormapEntries - mask;
        base = lowbit(mask);
        for (pixel = 0; pixel < entries; pixel++) {
            if (pixel & mask)
                continue;
            maxp = 0;
            /* check if all are free */
            while (ent[pixel + maxp].refcnt == 0) {
                GetNextBitsOrBreak(maxp, mask, base);
            }
            if ((maxp < mask) || (ent[pixel + mask].refcnt != 0))
                continue;
            /* this one works */
            *ppix++ = pixel;
            found++;
            if (found < count)
                continue;
            /* found enough, allocate them all */
            while (--count >= 0) {
                pixel = (pixels)[count];
                maxp = 0;
                while (1) {
                    ent[pixel + maxp].refcnt = AllocPrivate;
                    ent[pixel + maxp].fShared = FALSE;
                    GetNextBitsOrBreak(maxp, mask, base);
                    *ppix++ = pixel + maxp;
                }
            }

            *pMask = mask;
            return TRUE;
        }
    }
    return FALSE;
}

/**
 *
 *  \param ppixFirst  First of the client's new pixels
 */
static Bool
AllocShared(ColormapPtr pmap, Pixel * ppix, int c, int r, int g, int b,
            Pixel rmask, Pixel gmask, Pixel bmask, Pixel * ppixFirst)
{
    Pixel *pptr, *cptr;
    int npix, z, npixClientNew, npixShared;
    Pixel basemask, base, bits, common;
    SHAREDCOLOR *pshared, **ppshared, **psharedList;

    npixClientNew = c << (r + g + b);
    npixShared = (c << r) + (c << g) + (c << b);
    psharedList = xallocarray(npixShared, sizeof(SHAREDCOLOR *));
    if (!psharedList)
        return FALSE;
    ppshared = psharedList;
    for (z = npixShared; --z >= 0;) {
        if (!(ppshared[z] = malloc(sizeof(SHAREDCOLOR)))) {
            for (z++; z < npixShared; z++)
                free(ppshared[z]);
            free(psharedList);
            return FALSE;
        }
    }
    for (pptr = ppix, npix = c; --npix >= 0; pptr++) {
        basemask = ~(gmask | bmask);
        common = *pptr & basemask;
        if (rmask) {
            bits = 0;
            base = lowbit(rmask);
            while (1) {
                pshared = *ppshared++;
                pshared->refcnt = 1 << (g + b);
                for (cptr = ppixFirst, z = npixClientNew; --z >= 0; cptr++) {
                    if ((*cptr & basemask) == (common | bits)) {
                        pmap->red[*cptr].fShared = TRUE;
                        pmap->red[*cptr].co.shco.red = pshared;
                    }
                }
                GetNextBitsOrBreak(bits, rmask, base);
            }
        }
        else {
            pshared = *ppshared++;
            pshared->refcnt = 1 << (g + b);
            for (cptr = ppixFirst, z = npixClientNew; --z >= 0; cptr++) {
                if ((*cptr & basemask) == common) {
                    pmap->red[*cptr].fShared = TRUE;
                    pmap->red[*cptr].co.shco.red = pshared;
                }
            }
        }
        basemask = ~(rmask | bmask);
        common = *pptr & basemask;
        if (gmask) {
            bits = 0;
            base = lowbit(gmask);
            while (1) {
                pshared = *ppshared++;
                pshared->refcnt = 1 << (r + b);
                for (cptr = ppixFirst, z = npixClientNew; --z >= 0; cptr++) {
                    if ((*cptr & basemask) == (common | bits)) {
                        pmap->red[*cptr].co.shco.green = pshared;
                    }
                }
                GetNextBitsOrBreak(bits, gmask, base);
            }
        }
        else {
            pshared = *ppshared++;
            pshared->refcnt = 1 << (g + b);
            for (cptr = ppixFirst, z = npixClientNew; --z >= 0; cptr++) {
                if ((*cptr & basemask) == common) {
                    pmap->red[*cptr].co.shco.green = pshared;
                }
            }
        }
        basemask = ~(rmask | gmask);
        common = *pptr & basemask;
        if (bmask) {
            bits = 0;
            base = lowbit(bmask);
            while (1) {
                pshared = *ppshared++;
                pshared->refcnt = 1 << (r + g);
                for (cptr = ppixFirst, z = npixClientNew; --z >= 0; cptr++) {
                    if ((*cptr & basemask) == (common | bits)) {
                        pmap->red[*cptr].co.shco.blue = pshared;
                    }
                }
                GetNextBitsOrBreak(bits, bmask, base);
            }
        }
        else {
            pshared = *ppshared++;
            pshared->refcnt = 1 << (g + b);
            for (cptr = ppixFirst, z = npixClientNew; --z >= 0; cptr++) {
                if ((*cptr & basemask) == common) {
                    pmap->red[*cptr].co.shco.blue = pshared;
                }
            }
        }
    }
    free(psharedList);
    return TRUE;
}

/** FreeColors
 * Free colors and/or cells (probably slow for large numbers)
 */
int
FreeColors(ColormapPtr pmap, int client, int count, Pixel * pixels, Pixel mask)
{
    int rval, result, class;
    Pixel rmask;

    class = pmap->class;
    if (pmap->flags & AllAllocated)
        return BadAccess;
    if ((class | DynamicClass) == DirectColor) {
        rmask = mask & RGBMASK(pmap->pVisual);
        result = FreeCo(pmap, client, REDMAP, count, pixels,
                        mask & pmap->pVisual->redMask);
        /* If any of the three calls fails, we must report that, if more
         * than one fails, it's ok that we report the last one */
        rval = FreeCo(pmap, client, GREENMAP, count, pixels,
                      mask & pmap->pVisual->greenMask);
        if (rval != Success)
            result = rval;
        rval = FreeCo(pmap, client, BLUEMAP, count, pixels,
                      mask & pmap->pVisual->blueMask);
        if (rval != Success)
            result = rval;
    }
    else {
        rmask = mask & ((((Pixel) 1) << pmap->pVisual->nplanes) - 1);
        result = FreeCo(pmap, client, PSEUDOMAP, count, pixels, rmask);
    }
    if ((mask != rmask) && count) {
        clients[client]->errorValue = *pixels | mask;
        result = BadValue;
    }
    /* XXX should worry about removing any RT_CMAPENTRY resource */
    return result;
}

/**
 * Helper for FreeColors -- frees all combinations of *newpixels and mask bits
 * which the client has allocated in channel colormap cells of pmap.
 * doesn't change newpixels if it doesn't need to
 *
 *  \param pmap   which colormap head
 *  \param color  which sub-map, eg, RED, BLUE, PSEUDO
 *  \param npixIn number of pixels passed in
 *  \param ppixIn number of base pixels
 *  \param mask   mask client gave us
 */
static int
FreeCo(ColormapPtr pmap, int client, int color, int npixIn, Pixel * ppixIn,
       Pixel mask)
{
    Pixel *ppixClient, pixTest;
    int npixClient, npixNew, npix;
    Pixel bits, base, cmask, rgbbad;
    Pixel *pptr, *cptr;
    int n, zapped;
    int errVal = Success;
    int offset, numents;

    if (npixIn == 0)
        return errVal;
    bits = 0;
    zapped = 0;
    base = lowbit(mask);

    switch (color) {
    case REDMAP:
        cmask = pmap->pVisual->redMask;
        rgbbad = ~RGBMASK(pmap->pVisual);
        offset = pmap->pVisual->offsetRed;
        numents = (cmask >> offset) + 1;
        ppixClient = pmap->clientPixelsRed[client];
        npixClient = pmap->numPixelsRed[client];
        break;
    case GREENMAP:
        cmask = pmap->pVisual->greenMask;
        rgbbad = ~RGBMASK(pmap->pVisual);
        offset = pmap->pVisual->offsetGreen;
        numents = (cmask >> offset) + 1;
        ppixClient = pmap->clientPixelsGreen[client];
        npixClient = pmap->numPixelsGreen[client];
        break;
    case BLUEMAP:
        cmask = pmap->pVisual->blueMask;
        rgbbad = ~RGBMASK(pmap->pVisual);
        offset = pmap->pVisual->offsetBlue;
        numents = (cmask >> offset) + 1;
        ppixClient = pmap->clientPixelsBlue[client];
        npixClient = pmap->numPixelsBlue[client];
        break;
    default:        /* so compiler can see that everything gets initialized */
    case PSEUDOMAP:
        cmask = ~((Pixel) 0);
        rgbbad = 0;
        offset = 0;
        numents = pmap->pVisual->ColormapEntries;
        ppixClient = pmap->clientPixelsRed[client];
        npixClient = pmap->numPixelsRed[client];
        break;
    }

    /* zap all pixels which match */
    while (1) {
        /* go through pixel list */
        for (pptr = ppixIn, n = npixIn; --n >= 0; pptr++) {
            pixTest = ((*pptr | bits) & cmask) >> offset;
            if ((pixTest >= numents) || (*pptr & rgbbad)) {
                clients[client]->errorValue = *pptr | bits;
                errVal = BadValue;
                continue;
            }

            /* find match in client list */
            for (cptr = ppixClient, npix = npixClient;
                 --npix >= 0 && *cptr != pixTest; cptr++);

            if (npix >= 0) {
                if (pmap->class & DynamicClass) {
                    FreeCell(pmap, pixTest, color);
                }
                *cptr = ~((Pixel) 0);
                zapped++;
            }
            else
                errVal = BadAccess;
        }
        /* generate next bits value */
        GetNextBitsOrBreak(bits, mask, base);
    }

    /* delete freed pixels from client pixel list */
    if (zapped) {
        npixNew = npixClient - zapped;
        if (npixNew) {
            /* Since the list can only get smaller, we can do a copy in
             * place and then realloc to a smaller size */
            pptr = cptr = ppixClient;

            /* If we have all the new pixels, we don't have to examine the
             * rest of the old ones */
            for (npix = 0; npix < npixNew; cptr++) {
                if (*cptr != ~((Pixel) 0)) {
                    *pptr++ = *cptr;
                    npix++;
                }
            }
            pptr = reallocarray(ppixClient, npixNew, sizeof(Pixel));
            if (pptr)
                ppixClient = pptr;
            npixClient = npixNew;
        }
        else {
            npixClient = 0;
            free(ppixClient);
            ppixClient = (Pixel *) NULL;
        }
        switch (color) {
        case PSEUDOMAP:
        case REDMAP:
            pmap->clientPixelsRed[client] = ppixClient;
            pmap->numPixelsRed[client] = npixClient;
            break;
        case GREENMAP:
            pmap->clientPixelsGreen[client] = ppixClient;
            pmap->numPixelsGreen[client] = npixClient;
            break;
        case BLUEMAP:
            pmap->clientPixelsBlue[client] = ppixClient;
            pmap->numPixelsBlue[client] = npixClient;
            break;
        }
    }
    return errVal;
}

/* Redefine color values */
int
StoreColors(ColormapPtr pmap, int count, xColorItem * defs, ClientPtr client)
{
    Pixel pix;
    xColorItem *pdef;
    EntryPtr pent, pentT, pentLast;
    VisualPtr pVisual;
    SHAREDCOLOR *pred, *pgreen, *pblue;
    int n, ChgRed, ChgGreen, ChgBlue, idef;
    int class, errVal = Success;
    int ok;

    class = pmap->class;
    if (!(class & DynamicClass) && !(pmap->flags & BeingCreated)) {
        return BadAccess;
    }
    pVisual = pmap->pVisual;

    idef = 0;
    if ((class | DynamicClass) == DirectColor) {
        int numred, numgreen, numblue;
        Pixel rgbbad;

        numred = NUMRED(pVisual);
        numgreen = NUMGREEN(pVisual);
        numblue = NUMBLUE(pVisual);
        rgbbad = ~RGBMASK(pVisual);
        for (pdef = defs, n = 0; n < count; pdef++, n++) {
            ok = TRUE;
            (*pmap->pScreen->ResolveColor)
                (&pdef->red, &pdef->green, &pdef->blue, pmap->pVisual);

            if (pdef->pixel & rgbbad) {
                errVal = BadValue;
                client->errorValue = pdef->pixel;
                continue;
            }
            pix = (pdef->pixel & pVisual->redMask) >> pVisual->offsetRed;
            if (pix >= numred) {
                errVal = BadValue;
                ok = FALSE;
            }
            else if (pmap->red[pix].refcnt != AllocPrivate) {
                errVal = BadAccess;
                ok = FALSE;
            }
            else if (pdef->flags & DoRed) {
                pmap->red[pix].co.local.red = pdef->red;
            }
            else {
                pdef->red = pmap->red[pix].co.local.red;
            }

            pix = (pdef->pixel & pVisual->greenMask) >> pVisual->offsetGreen;
            if (pix >= numgreen) {
                errVal = BadValue;
                ok = FALSE;
            }
            else if (pmap->green[pix].refcnt != AllocPrivate) {
                errVal = BadAccess;
                ok = FALSE;
            }
            else if (pdef->flags & DoGreen) {
                pmap->green[pix].co.local.green = pdef->green;
            }
            else {
                pdef->green = pmap->green[pix].co.local.green;
            }

            pix = (pdef->pixel & pVisual->blueMask) >> pVisual->offsetBlue;
            if (pix >= numblue) {
                errVal = BadValue;
                ok = FALSE;
            }
            else if (pmap->blue[pix].refcnt != AllocPrivate) {
                errVal = BadAccess;
                ok = FALSE;
            }
            else if (pdef->flags & DoBlue) {
                pmap->blue[pix].co.local.blue = pdef->blue;
            }
            else {
                pdef->blue = pmap->blue[pix].co.local.blue;
            }
            /* If this is an o.k. entry, then it gets added to the list
             * to be sent to the hardware.  If not, skip it.  Once we've
             * skipped one, we have to copy all the others.
             */
            if (ok) {
                if (idef != n)
                    defs[idef] = defs[n];
                idef++;
            }
            else
                client->errorValue = pdef->pixel;
        }
    }
    else {
        for (pdef = defs, n = 0; n < count; pdef++, n++) {

            ok = TRUE;
            if (pdef->pixel >= pVisual->ColormapEntries) {
                client->errorValue = pdef->pixel;
                errVal = BadValue;
                ok = FALSE;
            }
            else if (pmap->red[pdef->pixel].refcnt != AllocPrivate) {
                errVal = BadAccess;
                ok = FALSE;
            }

            /* If this is an o.k. entry, then it gets added to the list
             * to be sent to the hardware.  If not, skip it.  Once we've
             * skipped one, we have to copy all the others.
             */
            if (ok) {
                if (idef != n)
                    defs[idef] = defs[n];
                idef++;
            }
            else
                continue;

            (*pmap->pScreen->ResolveColor)
                (&pdef->red, &pdef->green, &pdef->blue, pmap->pVisual);

            pent = &pmap->red[pdef->pixel];

            if (pdef->flags & DoRed) {
                if (pent->fShared) {
                    pent->co.shco.red->color = pdef->red;
                    if (pent->co.shco.red->refcnt > 1)
                        ok = FALSE;
                }
                else
                    pent->co.local.red = pdef->red;
            }
            else {
                if (pent->fShared)
                    pdef->red = pent->co.shco.red->color;
                else
                    pdef->red = pent->co.local.red;
            }
            if (pdef->flags & DoGreen) {
                if (pent->fShared) {
                    pent->co.shco.green->color = pdef->green;
                    if (pent->co.shco.green->refcnt > 1)
                        ok = FALSE;
                }
                else
                    pent->co.local.green = pdef->green;
            }
            else {
                if (pent->fShared)
                    pdef->green = pent->co.shco.green->color;
                else
                    pdef->green = pent->co.local.green;
            }
            if (pdef->flags & DoBlue) {
                if (pent->fShared) {
                    pent->co.shco.blue->color = pdef->blue;
                    if (pent->co.shco.blue->refcnt > 1)
                        ok = FALSE;
                }
                else
                    pent->co.local.blue = pdef->blue;
            }
            else {
                if (pent->fShared)
                    pdef->blue = pent->co.shco.blue->color;
                else
                    pdef->blue = pent->co.local.blue;
            }

            if (!ok) {
                /* have to run through the colormap and change anybody who
                 * shares this value */
                pred = pent->co.shco.red;
                pgreen = pent->co.shco.green;
                pblue = pent->co.shco.blue;
                ChgRed = pdef->flags & DoRed;
                ChgGreen = pdef->flags & DoGreen;
                ChgBlue = pdef->flags & DoBlue;
                pentLast = pmap->red + pVisual->ColormapEntries;

                for (pentT = pmap->red; pentT < pentLast; pentT++) {
                    if (pentT->fShared && (pentT != pent)) {
                        xColorItem defChg;

                        /* There are, alas, devices in this world too dumb
                         * to read their own hardware colormaps.  Sick, but
                         * true.  So we're going to be really nice and load
                         * the xColorItem with the proper value for all the
                         * fields.  We will only set the flags for those
                         * fields that actually change.  Smart devices can
                         * arrange to change only those fields.  Dumb devices
                         * can rest assured that we have provided for them,
                         * and can change all three fields */

                        defChg.flags = 0;
                        if (ChgRed && pentT->co.shco.red == pred) {
                            defChg.flags |= DoRed;
                        }
                        if (ChgGreen && pentT->co.shco.green == pgreen) {
                            defChg.flags |= DoGreen;
                        }
                        if (ChgBlue && pentT->co.shco.blue == pblue) {
                            defChg.flags |= DoBlue;
                        }
                        if (defChg.flags != 0) {
                            defChg.pixel = pentT - pmap->red;
                            defChg.red = pentT->co.shco.red->color;
                            defChg.green = pentT->co.shco.green->color;
                            defChg.blue = pentT->co.shco.blue->color;
                            (*pmap->pScreen->StoreColors) (pmap, 1, &defChg);
                        }
                    }
                }

            }
        }
    }
    /* Note that we use idef, the count of acceptable entries, and not
     * count, the count of proposed entries */
    if (idef != 0)
        (*pmap->pScreen->StoreColors) (pmap, idef, defs);
    return errVal;
}

int
IsMapInstalled(Colormap map, WindowPtr pWin)
{
    Colormap *pmaps;
    int imap, nummaps, found;

    pmaps = xallocarray(pWin->drawable.pScreen->maxInstalledCmaps,
                        sizeof(Colormap));
    if (!pmaps)
        return FALSE;
    nummaps = (*pWin->drawable.pScreen->ListInstalledColormaps)
        (pWin->drawable.pScreen, pmaps);
    found = FALSE;
    for (imap = 0; imap < nummaps; imap++) {
        if (pmaps[imap] == map) {
            found = TRUE;
            break;
        }
    }
    free(pmaps);
    return found;
}

struct colormap_lookup_data {
    ScreenPtr pScreen;
    VisualPtr visuals;
};

static void
_colormap_find_resource(void *value, XID id, void *cdata)
{
    struct colormap_lookup_data *cmap_data = cdata;
    VisualPtr visuals = cmap_data->visuals;
    ScreenPtr pScreen = cmap_data->pScreen;
    ColormapPtr cmap = value;
    int j;

    if (pScreen != cmap->pScreen)
        return;

    j = cmap->pVisual - pScreen->visuals;
    cmap->pVisual = &visuals[j];
}

/* something has realloced the visuals, instead of breaking
   ABI fix it up here - glx and composite did this wrong */
Bool
ResizeVisualArray(ScreenPtr pScreen, int new_visual_count, DepthPtr depth)
{
    struct colormap_lookup_data cdata;
    int numVisuals;
    VisualPtr visuals;
    XID *vids, vid;
    int first_new_vid, first_new_visual, i;

    first_new_vid = depth->numVids;
    first_new_visual = pScreen->numVisuals;

    vids = reallocarray(depth->vids, depth->numVids + new_visual_count,
                        sizeof(XID));
    if (!vids)
        return FALSE;

    /* its realloced now no going back if we fail the next one */
    depth->vids = vids;

    numVisuals = pScreen->numVisuals + new_visual_count;
    visuals = reallocarray(pScreen->visuals, numVisuals, sizeof(VisualRec));
    if (!visuals) {
        return FALSE;
    }

    cdata.visuals = visuals;
    cdata.pScreen = pScreen;
    FindClientResourcesByType(serverClient, RT_COLORMAP,
                              _colormap_find_resource, &cdata);

    pScreen->visuals = visuals;

    for (i = 0; i < new_visual_count; i++) {
        vid = FakeClientID(0);
        pScreen->visuals[first_new_visual + i].vid = vid;
        vids[first_new_vid + i] = vid;
    }

    depth->numVids += new_visual_count;
    pScreen->numVisuals += new_visual_count;

    return TRUE;
}
