path: root/hw/vfb/InitOutput.c

/* $Xorg: InitOutput.c,v 1.4 2001/02/09 02:04:45 xorgcvs Exp $ */
/*

Copyright 1993, 1998  The Open Group

Permission to use, copy, modify, distribute, and sell this software and its
documentation for any purpose is hereby granted without fee, provided that
the above copyright notice appear in all copies and that both that
copyright notice and this permission notice appear in supporting
documentation.

The above copyright notice and this permission notice shall be included
in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
IN NO EVENT SHALL THE OPEN GROUP BE LIABLE FOR ANY CLAIM, DAMAGES OR
OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
OTHER DEALINGS IN THE SOFTWARE.

Except as contained in this notice, the name of The Open Group shall
not be used in advertising or otherwise to promote the sale, use or
other dealings in this Software without prior written authorization
from The Open Group.

*/
/* $XFree86: xc/programs/Xserver/hw/vfb/InitOutput.c,v 3.25 2003/11/15 04:01:56 dawes Exp $ */

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

#if defined(WIN32)
#include <X11/Xwinsock.h>
#endif
#include <stdio.h>
#include <X11/X.h>
#define NEED_EVENTS
#include <X11/Xproto.h>
#include <X11/Xos.h>
#include "scrnintstr.h"
#include "servermd.h"
#define PSZ 8
#include "fb.h"
#include "mibstore.h"
#include "colormapst.h"
#include "gcstruct.h"
#include "input.h"
#include "mipointer.h"
#include "micmap.h"
#include <sys/types.h>
#ifdef HAS_MMAP
#include <sys/mman.h>
#ifndef MAP_FILE
#define MAP_FILE 0
#endif
#endif /* HAS_MMAP */
#include <sys/stat.h>
#include <errno.h>
#ifndef WIN32
#include <sys/param.h>
#endif
#include <X11/XWDFile.h>
#ifdef HAS_SHM
#include <sys/ipc.h>
#include <sys/shm.h>
#endif /* HAS_SHM */
#include "dix.h"
#include "miline.h"

#define VFB_DEFAULT_WIDTH      1280
#define VFB_DEFAULT_HEIGHT     1024
#define VFB_DEFAULT_DEPTH         8
#define VFB_DEFAULT_WHITEPIXEL    1
#define VFB_DEFAULT_BLACKPIXEL    0
#define VFB_DEFAULT_LINEBIAS      0
#define XWD_WINDOW_NAME_LEN      60

typedef struct
{
    int scrnum;
    int width;
    int paddedBytesWidth;
    int paddedWidth;
    int height;
    int depth;
    int bitsPerPixel;
    int sizeInBytes;
    int ncolors;
    char *pfbMemory;
    XWDColor *pXWDCmap;
    XWDFileHeader *pXWDHeader;
    Pixel blackPixel;
    Pixel whitePixel;
    unsigned int lineBias;
    CloseScreenProcPtr closeScreen;

#ifdef HAS_MMAP
    int mmap_fd;
    char mmap_file[MAXPATHLEN];
#endif

#ifdef HAS_SHM
    int shmid;
#endif
} vfbScreenInfo, *vfbScreenInfoPtr;

static int vfbNumScreens;
static vfbScreenInfo vfbScreens[MAXSCREENS];
static Bool vfbPixmapDepths[33];
#ifdef HAS_MMAP
static char *pfbdir = NULL;
#endif
typedef enum { NORMAL_MEMORY_FB, SHARED_MEMORY_FB, MMAPPED_FILE_FB } fbMemType;
static fbMemType fbmemtype = NORMAL_MEMORY_FB;
static char needswap = 0;
static int lastScreen = -1;
static Bool Render = TRUE;

#define swapcopy16(_dst, _src) \
    if (needswap) { CARD16 _s = _src; cpswaps(_s, _dst); } \
    else _dst = _src;

#define swapcopy32(_dst, _src) \
    if (needswap) { CARD32 _s = _src; cpswapl(_s, _dst); } \
    else _dst = _src;


static void
vfbInitializePixmapDepths(void)
{
    int i;
    vfbPixmapDepths[1] = TRUE; /* always need bitmaps */
    for (i = 2; i <= 32; i++)
	vfbPixmapDepths[i] = FALSE;
}

static void
vfbInitializeDefaultScreens(void)
{
    int i;

    for (i = 0; i < MAXSCREENS; i++)
    {
	vfbScreens[i].scrnum = i;
	vfbScreens[i].width  = VFB_DEFAULT_WIDTH;
	vfbScreens[i].height = VFB_DEFAULT_HEIGHT;
	vfbScreens[i].depth  = VFB_DEFAULT_DEPTH;
	vfbScreens[i].blackPixel = VFB_DEFAULT_BLACKPIXEL;
	vfbScreens[i].whitePixel = VFB_DEFAULT_WHITEPIXEL;
	vfbScreens[i].lineBias = VFB_DEFAULT_LINEBIAS;
	vfbScreens[i].pfbMemory = NULL;
    }
    vfbNumScreens = 1;
}

static int
vfbBitsPerPixel(int depth)
{
    if (depth == 1) return 1;
    else if (depth <= 8) return 8;
    else if (depth <= 16) return 16;
    else return 32;
}

void
ddxGiveUp()
{
    int i;

    /* clean up the framebuffers */

    switch (fbmemtype)
    {
#ifdef HAS_MMAP
    case MMAPPED_FILE_FB: 
	for (i = 0; i < vfbNumScreens; i++)
	{
	    if (-1 == unlink(vfbScreens[i].mmap_file))
	    {
		perror("unlink");
		ErrorF("unlink %s failed, errno %d",
		       vfbScreens[i].mmap_file, errno);
	    }
	}
	break;
#else /* HAS_MMAP */
    case MMAPPED_FILE_FB:
        break;
#endif /* HAS_MMAP */
	
#ifdef HAS_SHM
    case SHARED_MEMORY_FB:
	for (i = 0; i < vfbNumScreens; i++)
	{
	    if (-1 == shmdt((char *)vfbScreens[i].pXWDHeader))
	    {
		perror("shmdt");
		ErrorF("shmdt failed, errno %d", errno);
	    }
	}
	break;
#else /* HAS_SHM */
    case SHARED_MEMORY_FB:
        break;
#endif /* HAS_SHM */
	
    case NORMAL_MEMORY_FB:
	for (i = 0; i < vfbNumScreens; i++)
	{
	    Xfree(vfbScreens[i].pXWDHeader);
	}
	break;
    }
}

void
AbortDDX()
{
    ddxGiveUp();
}

#ifdef __DARWIN__
void
DarwinHandleGUI(int argc, char *argv[])
{
}

void GlxExtensionInit();
void GlxWrapInitVisuals(void *procPtr);

void
DarwinGlxExtensionInit()
{
    GlxExtensionInit();
}

void
DarwinGlxWrapInitVisuals(
    void *procPtr)
{
    GlxWrapInitVisuals(procPtr);
}
#endif

void
OsVendorInit()
{
}

void
OsVendorFatalError()
{
}

void ddxBeforeReset(void)
{
    return;
}

void
ddxUseMsg()
{
    ErrorF("-screen scrn WxHxD     set screen's width, height, depth\n");
    ErrorF("-pixdepths list-of-int support given pixmap depths\n");
#ifdef RENDER
    ErrorF("+/-render		   turn on/of RENDER extension support"
	   "(default on)\n");
#endif
    ErrorF("-linebias n            adjust thin line pixelization\n");
    ErrorF("-blackpixel n          pixel value for black\n");
    ErrorF("-whitepixel n          pixel value for white\n");

#ifdef HAS_MMAP
    ErrorF("-fbdir directory       put framebuffers in mmap'ed files in directory\n");
#endif

#ifdef HAS_SHM
    ErrorF("-shmem                 put framebuffers in shared memory\n");
#endif
}

/* ddxInitGlobals - called by |InitGlobals| from os/util.c */
void ddxInitGlobals(void)
{
}

int
ddxProcessArgument(int argc, char *argv[], int i)
{
    static Bool firstTime = TRUE;

    if (firstTime)
    {
	vfbInitializeDefaultScreens();
	vfbInitializePixmapDepths();
        firstTime = FALSE;
    }

#define CHECK_FOR_REQUIRED_ARGUMENTS(num) \
    if (((i + num) >= argc) || (!argv[i + num])) {                      \
      ErrorF("Required argument to %s not specified\n", argv[i]);       \
      UseMsg();                                                         \
      FatalError("Required argument to %s not specified\n", argv[i]);   \
    }
    
    if (strcmp (argv[i], "-screen") == 0)	/* -screen n WxHxD */
    {
	int screenNum;
	CHECK_FOR_REQUIRED_ARGUMENTS(2);
	screenNum = atoi(argv[i+1]);
	if (screenNum < 0 || screenNum >= MAXSCREENS)
	{
	    ErrorF("Invalid screen number %d\n", screenNum);
	    UseMsg();
	    FatalError("Invalid screen number %d passed to -screen\n",
		       screenNum);
	}
	if (3 != sscanf(argv[i+2], "%dx%dx%d",
			&vfbScreens[screenNum].width,
			&vfbScreens[screenNum].height,
			&vfbScreens[screenNum].depth))
	{
	    ErrorF("Invalid screen configuration %s\n", argv[i+2]);
	    UseMsg();
	    FatalError("Invalid screen configuration %s for -screen %d\n",
		   argv[i+2], screenNum);
	}

	if (screenNum >= vfbNumScreens)
	    vfbNumScreens = screenNum + 1;
	lastScreen = screenNum;
	return 3;
    }

    if (strcmp (argv[i], "-pixdepths") == 0)	/* -pixdepths list-of-depth */
    {
	int depth, ret = 1;

	CHECK_FOR_REQUIRED_ARGUMENTS(1);
	while ((++i < argc) && (depth = atoi(argv[i])) != 0)
	{
	    if (depth < 0 || depth > 32)
	    {
		ErrorF("Invalid pixmap depth %d\n", depth);
		UseMsg();
		FatalError("Invalid pixmap depth %d passed to -pixdepths\n",
			   depth);
	    }
	    vfbPixmapDepths[depth] = TRUE;
	    ret++;
	}
	return ret;
    }

    if (strcmp (argv[i], "+render") == 0)	/* +render */
    {
	Render = TRUE;
	return 1;
    }

    if (strcmp (argv[i], "-render") == 0)	/* -render */
    {
	Render = FALSE;
	return 1;
    }

    if (strcmp (argv[i], "-blackpixel") == 0)	/* -blackpixel n */
    {
	Pixel pix;
	CHECK_FOR_REQUIRED_ARGUMENTS(1);
	pix = atoi(argv[++i]);
	if (-1 == lastScreen)
	{
	    int i;
	    for (i = 0; i < MAXSCREENS; i++)
	    {
		vfbScreens[i].blackPixel = pix;
	    }
	}
	else
	{
	    vfbScreens[lastScreen].blackPixel = pix;
	}
	return 2;
    }

    if (strcmp (argv[i], "-whitepixel") == 0)	/* -whitepixel n */
    {
	Pixel pix;
	CHECK_FOR_REQUIRED_ARGUMENTS(1);
	pix = atoi(argv[++i]);
	if (-1 == lastScreen)
	{
	    int i;
	    for (i = 0; i < MAXSCREENS; i++)
	    {
		vfbScreens[i].whitePixel = pix;
	    }
	}
	else
	{
	    vfbScreens[lastScreen].whitePixel = pix;
	}
	return 2;
    }

    if (strcmp (argv[i], "-linebias") == 0)	/* -linebias n */
    {
	unsigned int linebias;
	CHECK_FOR_REQUIRED_ARGUMENTS(1);
	linebias = atoi(argv[++i]);
	if (-1 == lastScreen)
	{
	    int i;
	    for (i = 0; i < MAXSCREENS; i++)
	    {
		vfbScreens[i].lineBias = linebias;
	    }
	}
	else
	{
	    vfbScreens[lastScreen].lineBias = linebias;
	}
	return 2;
    }

#ifdef HAS_MMAP
    if (strcmp (argv[i], "-fbdir") == 0)	/* -fbdir directory */
    {
	CHECK_FOR_REQUIRED_ARGUMENTS(1);
	pfbdir = argv[++i];
	fbmemtype = MMAPPED_FILE_FB;
	return 2;
    }
#endif /* HAS_MMAP */

#ifdef HAS_SHM
    if (strcmp (argv[i], "-shmem") == 0)	/* -shmem */
    {
	fbmemtype = SHARED_MEMORY_FB;
	return 1;
    }
#endif

    return 0;
}

#ifdef DDXTIME /* from ServerOSDefines */
CARD32
GetTimeInMillis()
{
    struct timeval  tp;

    X_GETTIMEOFDAY(&tp);
    return(tp.tv_sec * 1000) + (tp.tv_usec / 1000);
}
#endif

static ColormapPtr InstalledMaps[MAXSCREENS];

static int
vfbListInstalledColormaps(ScreenPtr pScreen, Colormap *pmaps)
{
    /* By the time we are processing requests, we can guarantee that there
     * is always a colormap installed */
    *pmaps = InstalledMaps[pScreen->myNum]->mid;
    return (1);
}


static void
vfbInstallColormap(ColormapPtr pmap)
{
    int index = pmap->pScreen->myNum;
    ColormapPtr oldpmap = InstalledMaps[index];

    if (pmap != oldpmap)
    {
	int entries;
	XWDFileHeader *pXWDHeader;
	XWDColor *pXWDCmap;
	VisualPtr pVisual;
	Pixel *     ppix;
	xrgb *      prgb;
	xColorItem *defs;
	int i;

	if(oldpmap != (ColormapPtr)None)
	    WalkTree(pmap->pScreen, TellLostMap, (char *)&oldpmap->mid);
	/* Install pmap */
	InstalledMaps[index] = pmap;
	WalkTree(pmap->pScreen, TellGainedMap, (char *)&pmap->mid);

	entries = pmap->pVisual->ColormapEntries;
	pXWDHeader = vfbScreens[pmap->pScreen->myNum].pXWDHeader;
	pXWDCmap = vfbScreens[pmap->pScreen->myNum].pXWDCmap;
	pVisual = pmap->pVisual;

	swapcopy32(pXWDHeader->visual_class, pVisual->class);
	swapcopy32(pXWDHeader->red_mask, pVisual->redMask);
	swapcopy32(pXWDHeader->green_mask, pVisual->greenMask);
	swapcopy32(pXWDHeader->blue_mask, pVisual->blueMask);
	swapcopy32(pXWDHeader->bits_per_rgb, pVisual->bitsPerRGBValue);
	swapcopy32(pXWDHeader->colormap_entries, pVisual->ColormapEntries);

	ppix = (Pixel *)ALLOCATE_LOCAL(entries * sizeof(Pixel));
	prgb = (xrgb *)ALLOCATE_LOCAL(entries * sizeof(xrgb));
	defs = (xColorItem *)ALLOCATE_LOCAL(entries * sizeof(xColorItem));

	for (i = 0; i < entries; i++)  ppix[i] = i;
	/* XXX truecolor */
	QueryColors(pmap, entries, ppix, prgb);

	for (i = 0; i < entries; i++) { /* convert xrgbs to xColorItems */
	    defs[i].pixel = ppix[i] & 0xff; /* change pixel to index */
	    defs[i].red = prgb[i].red;
	    defs[i].green = prgb[i].green;
	    defs[i].blue = prgb[i].blue;
	    defs[i].flags =  DoRed|DoGreen|DoBlue;
	}
	(*pmap->pScreen->StoreColors)(pmap, entries, defs);

	DEALLOCATE_LOCAL(ppix);
	DEALLOCATE_LOCAL(prgb);
	DEALLOCATE_LOCAL(defs);
    }
}

static void
vfbUninstallColormap(ColormapPtr pmap)
{
    ColormapPtr curpmap = InstalledMaps[pmap->pScreen->myNum];

    if(pmap == curpmap)
    {
	if (pmap->mid != pmap->pScreen->defColormap)
	{
	    curpmap = (ColormapPtr) LookupIDByType(pmap->pScreen->defColormap,
						   RT_COLORMAP);
	    (*pmap->pScreen->InstallColormap)(curpmap);
	}
    }
}

static void
vfbStoreColors(ColormapPtr pmap, int ndef, xColorItem *pdefs)
{
    XWDColor *pXWDCmap;
    int i;

    if (pmap != InstalledMaps[pmap->pScreen->myNum])
    {
	return;
    }

    pXWDCmap = vfbScreens[pmap->pScreen->myNum].pXWDCmap;

    if ((pmap->pVisual->class | DynamicClass) == DirectColor)
    {
	return;
    }

    for (i = 0; i < ndef; i++)
    {
	if (pdefs[i].flags & DoRed)
	{
	    swapcopy16(pXWDCmap[pdefs[i].pixel].red, pdefs[i].red);
	}
	if (pdefs[i].flags & DoGreen)
	{
	    swapcopy16(pXWDCmap[pdefs[i].pixel].green, pdefs[i].green);
	}
	if (pdefs[i].flags & DoBlue)
	{
	    swapcopy16(pXWDCmap[pdefs[i].pixel].blue, pdefs[i].blue);
	}
    }
}

static Bool
vfbSaveScreen(ScreenPtr pScreen, int on)
{
    return TRUE;
}

#ifdef HAS_MMAP

/* this flushes any changes to the screens out to the mmapped file */
static void
vfbBlockHandler(pointer blockData, OSTimePtr pTimeout, pointer pReadmask)
{
    int i;

    for (i = 0; i < vfbNumScreens; i++)
    {
#ifdef MS_ASYNC
	if (-1 == msync((caddr_t)vfbScreens[i].pXWDHeader,
			(size_t)vfbScreens[i].sizeInBytes, MS_ASYNC))
#else
	/* silly NetBSD and who else? */
	if (-1 == msync((caddr_t)vfbScreens[i].pXWDHeader,
			(size_t)vfbScreens[i].sizeInBytes))
#endif
	{
	    perror("msync");
	    ErrorF("msync failed, errno %d", errno);
	}
    }
}


static void
vfbWakeupHandler(pointer blockData, int result, pointer pReadmask)
{
}


static void
vfbAllocateMmappedFramebuffer(vfbScreenInfoPtr pvfb)
{
#define DUMMY_BUFFER_SIZE 65536
    char dummyBuffer[DUMMY_BUFFER_SIZE];
    int currentFileSize, writeThisTime;

    sprintf(pvfb->mmap_file, "%s/Xvfb_screen%d", pfbdir, pvfb->scrnum);
    if (-1 == (pvfb->mmap_fd = open(pvfb->mmap_file, O_CREAT|O_RDWR, 0666)))
    {
	perror("open");
	ErrorF("open %s failed, errno %d", pvfb->mmap_file, errno);
	return;
    }

    /* Extend the file to be the proper size */

    bzero(dummyBuffer, DUMMY_BUFFER_SIZE);
    for (currentFileSize = 0;
	 currentFileSize < pvfb->sizeInBytes;
	 currentFileSize += writeThisTime)
    {
	writeThisTime = min(DUMMY_BUFFER_SIZE,
			    pvfb->sizeInBytes - currentFileSize);
	if (-1 == write(pvfb->mmap_fd, dummyBuffer, writeThisTime))
	{
	    perror("write");
	    ErrorF("write %s failed, errno %d", pvfb->mmap_file, errno);
	    return;
	}
    }

    /* try to mmap the file */

    pvfb->pXWDHeader = (XWDFileHeader *)mmap((caddr_t)NULL, pvfb->sizeInBytes,
				    PROT_READ|PROT_WRITE,
				    MAP_FILE|MAP_SHARED,
				    pvfb->mmap_fd, 0);
    if (-1 == (long)pvfb->pXWDHeader)
    {
	perror("mmap");
	ErrorF("mmap %s failed, errno %d", pvfb->mmap_file, errno);
	pvfb->pXWDHeader = NULL;
	return;
    }

    if (!RegisterBlockAndWakeupHandlers(vfbBlockHandler, vfbWakeupHandler,
					NULL))
    {
	pvfb->pXWDHeader = NULL;
    }
}
#endif /* HAS_MMAP */


#ifdef HAS_SHM
static void
vfbAllocateSharedMemoryFramebuffer(vfbScreenInfoPtr pvfb)
{
    /* create the shared memory segment */

    pvfb->shmid = shmget(IPC_PRIVATE, pvfb->sizeInBytes, IPC_CREAT|0777);
    if (pvfb->shmid < 0)
    {
	perror("shmget");
	ErrorF("shmget %d bytes failed, errno %d", pvfb->sizeInBytes, errno);
	return;
    }

    /* try to attach it */

    pvfb->pXWDHeader = (XWDFileHeader *)shmat(pvfb->shmid, 0, 0);
    if (-1 == (long)pvfb->pXWDHeader)
    {
	perror("shmat");
	ErrorF("shmat failed, errno %d", errno);
	pvfb->pXWDHeader = NULL; 
	return;
    }

    ErrorF("screen %d shmid %d\n", pvfb->scrnum, pvfb->shmid);
}
#endif /* HAS_SHM */

static char *
vfbAllocateFramebufferMemory(vfbScreenInfoPtr pvfb)
{
    if (pvfb->pfbMemory) return pvfb->pfbMemory; /* already done */

    pvfb->sizeInBytes = pvfb->paddedBytesWidth * pvfb->height;

    /* Calculate how many entries in colormap.  This is rather bogus, because
     * the visuals haven't even been set up yet, but we need to know because we
     * have to allocate space in the file for the colormap.  The number 10
     * below comes from the MAX_PSEUDO_DEPTH define in cfbcmap.c.
     */

    if (pvfb->depth <= 10)
    { /* single index colormaps */
	pvfb->ncolors = 1 << pvfb->depth;
    }
    else
    { /* decomposed colormaps */
	int nplanes_per_color_component = pvfb->depth / 3;
	if (pvfb->depth % 3) nplanes_per_color_component++;
	pvfb->ncolors = 1 << nplanes_per_color_component;
    }

    /* add extra bytes for XWDFileHeader, window name, and colormap */

    pvfb->sizeInBytes += SIZEOF(XWDheader) + XWD_WINDOW_NAME_LEN +
		    pvfb->ncolors * SIZEOF(XWDColor);

    pvfb->pXWDHeader = NULL; 
    switch (fbmemtype)
    {
#ifdef HAS_MMAP
    case MMAPPED_FILE_FB:  vfbAllocateMmappedFramebuffer(pvfb); break;
#else
    case MMAPPED_FILE_FB: break;
#endif

#ifdef HAS_SHM
    case SHARED_MEMORY_FB: vfbAllocateSharedMemoryFramebuffer(pvfb); break;
#else
    case SHARED_MEMORY_FB: break;
#endif

    case NORMAL_MEMORY_FB:
	pvfb->pXWDHeader = (XWDFileHeader *)Xalloc(pvfb->sizeInBytes);
	break;
    }

    if (pvfb->pXWDHeader)
    {
	pvfb->pXWDCmap = (XWDColor *)((char *)pvfb->pXWDHeader
				+ SIZEOF(XWDheader) + XWD_WINDOW_NAME_LEN);
	pvfb->pfbMemory = (char *)(pvfb->pXWDCmap + pvfb->ncolors);

	return pvfb->pfbMemory;
    }
    else
	return NULL;
}


static void
vfbWriteXWDFileHeader(ScreenPtr pScreen)
{
    vfbScreenInfoPtr pvfb = &vfbScreens[pScreen->myNum];
    XWDFileHeader *pXWDHeader = pvfb->pXWDHeader;
    char hostname[XWD_WINDOW_NAME_LEN];
    unsigned long swaptest = 1;
    int i;

    needswap = *(char *) &swaptest;

    pXWDHeader->header_size = (char *)pvfb->pXWDCmap - (char *)pvfb->pXWDHeader;
    pXWDHeader->file_version = XWD_FILE_VERSION;

    pXWDHeader->pixmap_format = ZPixmap;
    pXWDHeader->pixmap_depth = pvfb->depth;
    pXWDHeader->pixmap_height = pXWDHeader->window_height = pvfb->height;
    pXWDHeader->xoffset = 0;
    pXWDHeader->byte_order = IMAGE_BYTE_ORDER;
    pXWDHeader->bitmap_bit_order = BITMAP_BIT_ORDER;
#ifndef INTERNAL_VS_EXTERNAL_PADDING
    pXWDHeader->pixmap_width = pXWDHeader->window_width = pvfb->width;
    pXWDHeader->bitmap_unit = BITMAP_SCANLINE_UNIT;
    pXWDHeader->bitmap_pad = BITMAP_SCANLINE_PAD;
#else
    pXWDHeader->pixmap_width = pXWDHeader->window_width = pvfb->paddedWidth;
    pXWDHeader->bitmap_unit = BITMAP_SCANLINE_UNIT_PROTO;
    pXWDHeader->bitmap_pad = BITMAP_SCANLINE_PAD_PROTO;
#endif
    pXWDHeader->bits_per_pixel = pvfb->bitsPerPixel;
    pXWDHeader->bytes_per_line = pvfb->paddedBytesWidth;
    pXWDHeader->ncolors = pvfb->ncolors;

    /* visual related fields are written when colormap is installed */

    pXWDHeader->window_x = pXWDHeader->window_y = 0;
    pXWDHeader->window_bdrwidth = 0;

    /* write xwd "window" name: Xvfb hostname:server.screen */

    if (-1 == gethostname(hostname, sizeof(hostname)))
	hostname[0] = 0;
    else
	hostname[XWD_WINDOW_NAME_LEN-1] = 0;
    sprintf((char *)(pXWDHeader+1), "Xvfb %s:%s.%d", hostname, display,
	    pScreen->myNum);

    /* write colormap pixel slot values */

    for (i = 0; i < pvfb->ncolors; i++)
    {
	pvfb->pXWDCmap[i].pixel = i;
    }

    /* byte swap to most significant byte first */

    if (needswap)
    {
	SwapLongs((CARD32 *)pXWDHeader, SIZEOF(XWDheader)/4);
	for (i = 0; i < pvfb->ncolors; i++)
	{
	    register char n;
	    swapl(&pvfb->pXWDCmap[i].pixel, n);
	}
    }
}


static Bool
vfbCursorOffScreen (ScreenPtr *ppScreen, int *x, int *y)
{
    return FALSE;
}

static void
vfbCrossScreen (ScreenPtr pScreen, Bool entering)
{
}

static miPointerScreenFuncRec vfbPointerCursorFuncs =
{
    vfbCursorOffScreen,
    vfbCrossScreen,
    miPointerWarpCursor
};

static Bool
vfbCloseScreen(int index, ScreenPtr pScreen)
{
    vfbScreenInfoPtr pvfb = &vfbScreens[index];
    int i;
 
    pScreen->CloseScreen = pvfb->closeScreen;

    /*
     * XXX probably lots of stuff to clean.  For now,
     * clear InstalledMaps[] so that server reset works correctly.
     */
    for (i = 0; i < MAXSCREENS; i++)
	InstalledMaps[i] = NULL;

    return pScreen->CloseScreen(index, pScreen);
}

static Bool
vfbScreenInit(int index, ScreenPtr pScreen, int argc, char **argv)
{
    vfbScreenInfoPtr pvfb = &vfbScreens[index];
    int dpix = monitorResolution, dpiy = monitorResolution;
    int ret;
    char *pbits;
    
    if (dpix == 0)
      dpix = 100;

    if (dpiy == 0)
      dpiy = 100;

    pvfb->paddedBytesWidth = PixmapBytePad(pvfb->width, pvfb->depth);
    pvfb->bitsPerPixel = vfbBitsPerPixel(pvfb->depth);
    if (pvfb->bitsPerPixel >= 8 )
	pvfb->paddedWidth = pvfb->paddedBytesWidth / (pvfb->bitsPerPixel / 8);
    else
	pvfb->paddedWidth = pvfb->paddedBytesWidth * 8;
    pbits = vfbAllocateFramebufferMemory(pvfb);
    if (!pbits) return FALSE;

    miSetPixmapDepths ();

    switch (pvfb->depth) {
    case 8:
	miSetVisualTypesAndMasks (8,
				  ((1 << StaticGray) |
				   (1 << GrayScale) |
				   (1 << StaticColor) |
				   (1 << PseudoColor) |
				   (1 << TrueColor) |
				   (1 << DirectColor)),
				  8, PseudoColor, 0, 0, 0);
	break;
#if 0
    /* 12bit PseudoColor with 12bit color resolution
     * (to simulate SGI hardware and the 12bit PseudoColor emulation layer) */
    case 12:
	miSetVisualTypesAndMasks (12,
				  ((1 << StaticGray) |
				   (1 << GrayScale) |
				   (1 << StaticColor) |
				   (1 << PseudoColor) |
				   (1 << TrueColor) |
				   (1 << DirectColor)),
				  12, PseudoColor, 0, 0, 0);
	break;
#endif
    case 15:
	miSetVisualTypesAndMasks (15,
				  ((1 << TrueColor) |
				   (1 << DirectColor)),
				  8, TrueColor, 0x7c00, 0x03e0, 0x001f);
	break;
    case 16:
	miSetVisualTypesAndMasks (16,
				  ((1 << TrueColor) |
				   (1 << DirectColor)),
				  8, TrueColor, 0xf800, 0x07e0, 0x001f);
	break;
    case 24:
	miSetVisualTypesAndMasks (24,
				  ((1 << TrueColor) |
				   (1 << DirectColor)),
				  8, TrueColor, 0xff0000, 0x00ff00, 0x0000ff);
	break;
#if 0
    /* 30bit TrueColor (to simulate Sun's XVR-1000/-4000 high quality
     * framebuffer series) */
    case 30:
	miSetVisualTypesAndMasks (30,
				  ((1 << TrueColor) |
				   (1 << DirectColor)),
				  10, TrueColor, 0x3ff00000, 0x000ffc00, 0x000003ff);
	break;
#endif
    }
	
    ret = fbScreenInit(pScreen, pbits, pvfb->width, pvfb->height,
		       dpix, dpiy, pvfb->paddedWidth,pvfb->bitsPerPixel);
#ifdef RENDER
    if (ret && Render) 
	fbPictureInit (pScreen, 0, 0);
#endif

    if (!ret) return FALSE;

    miInitializeBackingStore(pScreen);

    /*
     * Circumvent the backing store that was just initialised.  This amounts
     * to a truely bizarre way of initialising SaveDoomedAreas and friends.
     */

    pScreen->InstallColormap = vfbInstallColormap;
    pScreen->UninstallColormap = vfbUninstallColormap;
    pScreen->ListInstalledColormaps = vfbListInstalledColormaps;

    pScreen->SaveScreen = vfbSaveScreen;
    pScreen->StoreColors = vfbStoreColors;

    miDCInitialize(pScreen, &vfbPointerCursorFuncs);

    vfbWriteXWDFileHeader(pScreen);

    pScreen->blackPixel = pvfb->blackPixel;
    pScreen->whitePixel = pvfb->whitePixel;

    ret = fbCreateDefColormap(pScreen);

    miSetZeroLineBias(pScreen, pvfb->lineBias);

    pvfb->closeScreen = pScreen->CloseScreen;
    pScreen->CloseScreen = vfbCloseScreen;

    return ret;

} /* end vfbScreenInit */


void
InitOutput(ScreenInfo *screenInfo, int argc, char **argv)
{
    int i;
    int NumFormats = 0;

    /* initialize pixmap formats */

    /* must have a pixmap depth to match every screen depth */
    for (i = 0; i < vfbNumScreens; i++)
    {
	vfbPixmapDepths[vfbScreens[i].depth] = TRUE;
    }

    /* RENDER needs a good set of pixmaps. */
    if (Render) {
	vfbPixmapDepths[1] = TRUE;
	vfbPixmapDepths[4] = TRUE;
	vfbPixmapDepths[8] = TRUE;
#if 0
	vfbPixmapDepths[12] = TRUE;
#endif
/*	vfbPixmapDepths[15] = TRUE; */
	vfbPixmapDepths[16] = TRUE;
	vfbPixmapDepths[24] = TRUE;
#if 0
	vfbPixmapDepths[30] = TRUE;
#endif
	vfbPixmapDepths[32] = TRUE;
    }

    for (i = 1; i <= 32; i++)
    {
	if (vfbPixmapDepths[i])
	{
	    if (NumFormats >= MAXFORMATS)
		FatalError ("MAXFORMATS is too small for this server\n");
	    screenInfo->formats[NumFormats].depth = i;
	    screenInfo->formats[NumFormats].bitsPerPixel = vfbBitsPerPixel(i);
	    screenInfo->formats[NumFormats].scanlinePad = BITMAP_SCANLINE_PAD;
	    NumFormats++;
	}
    }

    screenInfo->imageByteOrder = IMAGE_BYTE_ORDER;
    screenInfo->bitmapScanlineUnit = BITMAP_SCANLINE_UNIT;
    screenInfo->bitmapScanlinePad = BITMAP_SCANLINE_PAD;
    screenInfo->bitmapBitOrder = BITMAP_BIT_ORDER;
    screenInfo->numPixmapFormats = NumFormats;

    /* initialize screens */

    for (i = 0; i < vfbNumScreens; i++)
    {
	if (-1 == AddScreen(vfbScreenInit, argc, argv))
	{
	    FatalError("Couldn't add screen %d", i);
	}
    }

} /* end InitOutput */

/* this is just to get the server to link on AIX */
#ifdef AIXV3
int SelectWaitTime = 10000; /* usec */
#endif