src/gallium/winsys/sw/xlib/xlib_sw_winsys.c - platform/external/mesa3d - Git at Google

 /**************************************************************************
  *
  * Copyright 2007 Tungsten Graphics, Inc., Bismarck, ND., USA
  * All Rights Reserved.
  *
  * Permission is hereby granted, free of charge, to any person obtaining a
  * copy of this software and associated documentation files (the
  * "Software"), to deal in the Software without restriction, including
  * without limitation the rights to use, copy, modify, merge, publish,
  * distribute, sub license, and/or sell copies of the Software, and to
  * permit persons to whom the Software is furnished to do so, subject to
  * the following conditions:
  *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
  * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
  * USE OR OTHER DEALINGS IN THE SOFTWARE.
  *
  * The above copyright notice and this permission notice (including the
  * next paragraph) shall be included in all copies or substantial portions
  * of the Software.
  *
  *
  **************************************************************************/

 /*
  * Authors:
  *   Keith Whitwell
  *   Brian Paul
  */

 #include "pipe/p_format.h"
 #include "pipe/p_context.h"
 #include "util/u_inlines.h"
 #include "util/u_format.h"
 #include "util/u_math.h"
 #include "util/u_memory.h"

 #include "state_tracker/xlib_sw_winsys.h"

 #include <X11/Xlib.h>
 #include <X11/Xlibint.h>
 #include <X11/Xutil.h>
 #include <sys/ipc.h>
 #include <sys/shm.h>
 #include <X11/extensions/XShm.h>

 DEBUG_GET_ONCE_BOOL_OPTION(xlib_no_shm, "XLIB_NO_SHM", FALSE)

 /**
  * Display target for Xlib winsys.
  * Low-level OS/window system memory buffer
  */
 struct xlib_displaytarget
 {
    enum pipe_format format;
    unsigned width;
    unsigned height;
    unsigned stride;

    void *data;
    void *mapped;

    Display *display;
    Visual *visual;
    XImage *tempImage;
    GC gc;

    /* This is the last drawable that this display target was presented
     * against.  May need to recreate gc, tempImage when this changes??
     */
    Drawable drawable;

    XShmSegmentInfo shminfo;
    Bool shm;  /** Using shared memory images? */
 };


 /**
  * Subclass of sw_winsys for Xlib winsys
  */
 struct xlib_sw_winsys
 {
    struct sw_winsys base;
    Display *display;
 };


 /** Cast wrapper */
 static INLINE struct xlib_displaytarget *
 xlib_displaytarget(struct sw_displaytarget *dt)
 {
    return (struct xlib_displaytarget *) dt;
 }


 /**
  * X Shared Memory Image extension code
  */

 static volatile int XErrorFlag = 0;

 /**
  * Catches potential Xlib errors.
  */
 static int
 handle_xerror(Display *dpy, XErrorEvent *event)
 {
    (void) dpy;
    (void) event;
    XErrorFlag = 1;
    return 0;
 }


 static char *
 alloc_shm(struct xlib_displaytarget *buf, unsigned size)
 {
    XShmSegmentInfo *const shminfo = & buf->shminfo;

    shminfo->shmid = -1;
    shminfo->shmaddr = (char *) -1;

    shminfo->shmid = shmget(IPC_PRIVATE, size, IPC_CREAT|0777);
    if (shminfo->shmid < 0) {
       return NULL;
    }

    shminfo->shmaddr = (char *) shmat(shminfo->shmid, 0, 0);
    if (shminfo->shmaddr == (char *) -1) {
       shmctl(shminfo->shmid, IPC_RMID, 0);
       return NULL;
    }

    shminfo->readOnly = False;
    return shminfo->shmaddr;
 }


 /**
  * Allocate a shared memory XImage back buffer for the given display target.
  */
 static void
 alloc_shm_ximage(struct xlib_displaytarget *xlib_dt,
                  struct xlib_drawable *xmb,
                  unsigned width, unsigned height)
 {
    /*
     * We have to do a _lot_ of error checking here to be sure we can
     * really use the XSHM extension.  It seems different servers trigger
     * errors at different points if the extension won't work.  Therefore
     * we have to be very careful...
     */
    int (*old_handler)(Display *, XErrorEvent *);

    xlib_dt->tempImage = XShmCreateImage(xlib_dt->display,
                                       xmb->visual,
                                       xmb->depth,
                                       ZPixmap,
                                       NULL,
                                       &xlib_dt->shminfo,
                                       width, height);
    if (xlib_dt->tempImage == NULL) {
       xlib_dt->shm = False;
       return;
    }


    XErrorFlag = 0;
    old_handler = XSetErrorHandler(handle_xerror);
    /* This may trigger the X protocol error we're ready to catch: */
    XShmAttach(xlib_dt->display, &xlib_dt->shminfo);
    XSync(xlib_dt->display, False);

    if (XErrorFlag) {
       /* we are on a remote display, this error is normal, don't print it */
       XFlush(xlib_dt->display);
       XErrorFlag = 0;
       XDestroyImage(xlib_dt->tempImage);
       xlib_dt->tempImage = NULL;
       xlib_dt->shm = False;
       (void) XSetErrorHandler(old_handler);
       return;
    }

    xlib_dt->shm = True;
 }


 static void
 alloc_ximage(struct xlib_displaytarget *xlib_dt,
              struct xlib_drawable *xmb,
              unsigned width, unsigned height)
 {
    /* try allocating a shared memory image first */
    if (xlib_dt->shm) {
       alloc_shm_ximage(xlib_dt, xmb, width, height);
       if (xlib_dt->tempImage)
          return; /* success */
    }

    /* try regular (non-shared memory) image */
    xlib_dt->tempImage = XCreateImage(xlib_dt->display,
                                    xmb->visual,
                                    xmb->depth,
                                    ZPixmap, 0,
                                    NULL, width, height,
                                    8, 0);
 }

 static boolean
 xlib_is_displaytarget_format_supported(struct sw_winsys *ws,
                                        unsigned tex_usage,
                                        enum pipe_format format)
 {
    /* TODO: check visuals or other sensible thing here */
    return TRUE;
 }


 static void *
 xlib_displaytarget_map(struct sw_winsys *ws,
                        struct sw_displaytarget *dt,
                        unsigned flags)
 {
    struct xlib_displaytarget *xlib_dt = xlib_displaytarget(dt);
    xlib_dt->mapped = xlib_dt->data;
    return xlib_dt->mapped;
 }


 static void
 xlib_displaytarget_unmap(struct sw_winsys *ws,
                          struct sw_displaytarget *dt)
 {
    struct xlib_displaytarget *xlib_dt = xlib_displaytarget(dt);
    xlib_dt->mapped = NULL;
 }


 static void
 xlib_displaytarget_destroy(struct sw_winsys *ws,
                            struct sw_displaytarget *dt)
 {
    struct xlib_displaytarget *xlib_dt = xlib_displaytarget(dt);

    if (xlib_dt->data) {
       if (xlib_dt->shminfo.shmid >= 0) {
          shmdt(xlib_dt->shminfo.shmaddr);
          shmctl(xlib_dt->shminfo.shmid, IPC_RMID, 0);

          xlib_dt->shminfo.shmid = -1;
          xlib_dt->shminfo.shmaddr = (char *) -1;

          xlib_dt->data = NULL;
          if (xlib_dt->tempImage)
             xlib_dt->tempImage->data = NULL;
       }
       else {
          FREE(xlib_dt->data);
          if (xlib_dt->tempImage && xlib_dt->tempImage->data == xlib_dt->data) {
             xlib_dt->tempImage->data = NULL;
          }
          xlib_dt->data = NULL;
       }
    }

    if (xlib_dt->tempImage) {
       XDestroyImage(xlib_dt->tempImage);
       xlib_dt->tempImage = NULL;
    }

    if (xlib_dt->gc)
       XFreeGC(xlib_dt->display, xlib_dt->gc);

    FREE(xlib_dt);
 }


 /**
  * Display/copy the image in the surface into the X window specified
  * by the display target.
  */
 static void
 xlib_sw_display(struct xlib_drawable *xlib_drawable,
                 struct sw_displaytarget *dt)
 {
    static boolean no_swap = 0;
    static boolean firsttime = 1;
    struct xlib_displaytarget *xlib_dt = xlib_displaytarget(dt);
    Display *display = xlib_dt->display;
    XImage *ximage;

    if (firsttime) {
       no_swap = getenv("SP_NO_RAST") != NULL;
       firsttime = 0;
    }

    if (no_swap)
       return;

    if (xlib_dt->drawable != xlib_drawable->drawable) {
       if (xlib_dt->gc) {
          XFreeGC(display, xlib_dt->gc);
          xlib_dt->gc = NULL;
       }

       if (xlib_dt->tempImage) {
          XDestroyImage(xlib_dt->tempImage);
          xlib_dt->tempImage = NULL;
       }

       xlib_dt->drawable = xlib_drawable->drawable;
    }

    if (xlib_dt->tempImage == NULL) {
       assert(util_format_get_blockwidth(xlib_dt->format) == 1);
       assert(util_format_get_blockheight(xlib_dt->format) == 1);
       alloc_ximage(xlib_dt, xlib_drawable,
                    xlib_dt->stride / util_format_get_blocksize(xlib_dt->format),
                    xlib_dt->height);
       if (!xlib_dt->tempImage)
          return;
    }

    if (xlib_dt->gc == NULL) {
       xlib_dt->gc = XCreateGC(display, xlib_drawable->drawable, 0, NULL);
       XSetFunction(display, xlib_dt->gc, GXcopy);
    }

    if (xlib_dt->shm) {
       ximage = xlib_dt->tempImage;
       ximage->data = xlib_dt->data;

       /* _debug_printf("XSHM\n"); */
       XShmPutImage(xlib_dt->display, xlib_drawable->drawable, xlib_dt->gc,
                    ximage, 0, 0, 0, 0, xlib_dt->width, xlib_dt->height, False);
    }
    else {
       /* display image in Window */
       ximage = xlib_dt->tempImage;
       ximage->data = xlib_dt->data;

       /* check that the XImage has been previously initialized */
       assert(ximage->format);
       assert(ximage->bitmap_unit);

       /* update XImage's fields */
       ximage->width = xlib_dt->width;
       ximage->height = xlib_dt->height;
       ximage->bytes_per_line = xlib_dt->stride;

       /* _debug_printf("XPUT\n"); */
       XPutImage(xlib_dt->display, xlib_drawable->drawable, xlib_dt->gc,
                 ximage, 0, 0, 0, 0, xlib_dt->width, xlib_dt->height);
    }

    XFlush(xlib_dt->display);
 }


 /**
  * Display/copy the image in the surface into the X window specified
  * by the display target.
  */
 static void
 xlib_displaytarget_display(struct sw_winsys *ws,
                            struct sw_displaytarget *dt,
                            void *context_private)
 {
    struct xlib_drawable *xlib_drawable = (struct xlib_drawable *)context_private;
    xlib_sw_display(xlib_drawable, dt);
 }


 static struct sw_displaytarget *
 xlib_displaytarget_create(struct sw_winsys *winsys,
                           unsigned tex_usage,
                           enum pipe_format format,
                           unsigned width, unsigned height,
                           unsigned alignment,
                           unsigned *stride)
 {
    struct xlib_displaytarget *xlib_dt;
    unsigned nblocksy, size;

    xlib_dt = CALLOC_STRUCT(xlib_displaytarget);
    if (!xlib_dt)
       goto no_xlib_dt;

    xlib_dt->display = ((struct xlib_sw_winsys *)winsys)->display;
    xlib_dt->format = format;
    xlib_dt->width = width;
    xlib_dt->height = height;

    nblocksy = util_format_get_nblocksy(format, height);
    xlib_dt->stride = align(util_format_get_stride(format, width), alignment);
    size = xlib_dt->stride * nblocksy;

    if (!debug_get_option_xlib_no_shm()) {
       xlib_dt->data = alloc_shm(xlib_dt, size);
       if (xlib_dt->data) {
          xlib_dt->shm = True;
       }
    }

    if (!xlib_dt->data) {
       xlib_dt->data = align_malloc(size, alignment);
       if (!xlib_dt->data)
          goto no_data;
    }

    *stride = xlib_dt->stride;
    return (struct sw_displaytarget *)xlib_dt;

 no_data:
    FREE(xlib_dt);
 no_xlib_dt:
    return NULL;
 }


 static struct sw_displaytarget *
 xlib_displaytarget_from_handle(struct sw_winsys *winsys,
                                const struct pipe_resource *templet,
                                struct winsys_handle *whandle,
                                unsigned *stride)
 {
    assert(0);
    return NULL;
 }


 static boolean
 xlib_displaytarget_get_handle(struct sw_winsys *winsys,
                               struct sw_displaytarget *dt,
                               struct winsys_handle *whandle)
 {
    assert(0);
    return FALSE;
 }


 static void
 xlib_destroy(struct sw_winsys *ws)
 {
    FREE(ws);
 }


 struct sw_winsys *
 xlib_create_sw_winsys(Display *display)
 {
    struct xlib_sw_winsys *ws;

    ws = CALLOC_STRUCT(xlib_sw_winsys);
    if (!ws)
       return NULL;

    ws->display = display;
    ws->base.destroy = xlib_destroy;

    ws->base.is_displaytarget_format_supported = xlib_is_displaytarget_format_supported;

    ws->base.displaytarget_create = xlib_displaytarget_create;
    ws->base.displaytarget_from_handle = xlib_displaytarget_from_handle;
    ws->base.displaytarget_get_handle = xlib_displaytarget_get_handle;
    ws->base.displaytarget_map = xlib_displaytarget_map;
    ws->base.displaytarget_unmap = xlib_displaytarget_unmap;
    ws->base.displaytarget_destroy = xlib_displaytarget_destroy;

    ws->base.displaytarget_display = xlib_displaytarget_display;

    return &ws->base;
 }
	/**************************************************************************
	*
	* Copyright 2007 Tungsten Graphics, Inc., Bismarck, ND., USA
	* All Rights Reserved.
	*
	* Permission is hereby granted, free of charge, to any person obtaining a
	* copy of this software and associated documentation files (the
	* "Software"), to deal in the Software without restriction, including
	* without limitation the rights to use, copy, modify, merge, publish,
	* distribute, sub license, and/or sell copies of the Software, and to
	* permit persons to whom the Software is furnished to do so, subject to
	* the following conditions:
	*
	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	* FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
	* THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
	* DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
	* OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
	* USE OR OTHER DEALINGS IN THE SOFTWARE.
	*
	* The above copyright notice and this permission notice (including the
	* next paragraph) shall be included in all copies or substantial portions
	* of the Software.
	*
	*
	**************************************************************************/

	/*
	* Authors:
	* Keith Whitwell
	* Brian Paul
	*/

	#include "pipe/p_format.h"
	#include "pipe/p_context.h"
	#include "util/u_inlines.h"
	#include "util/u_format.h"
	#include "util/u_math.h"
	#include "util/u_memory.h"

	#include "state_tracker/xlib_sw_winsys.h"

	#include <X11/Xlib.h>
	#include <X11/Xlibint.h>
	#include <X11/Xutil.h>
	#include <sys/ipc.h>
	#include <sys/shm.h>
	#include <X11/extensions/XShm.h>

	DEBUG_GET_ONCE_BOOL_OPTION(xlib_no_shm, "XLIB_NO_SHM", FALSE)

	/**
	* Display target for Xlib winsys.
	* Low-level OS/window system memory buffer
	*/
	struct xlib_displaytarget
	{
	enum pipe_format format;
	unsigned width;
	unsigned height;
	unsigned stride;

	void *data;
	void *mapped;

	Display *display;
	Visual *visual;
	XImage *tempImage;
	GC gc;

	/* This is the last drawable that this display target was presented
	* against. May need to recreate gc, tempImage when this changes??
	*/
	Drawable drawable;

	XShmSegmentInfo shminfo;
	Bool shm; /** Using shared memory images? */
	};


	/**
	* Subclass of sw_winsys for Xlib winsys
	*/
	struct xlib_sw_winsys
	{
	struct sw_winsys base;
	Display *display;
	};



	/** Cast wrapper */
	static INLINE struct xlib_displaytarget *
	xlib_displaytarget(struct sw_displaytarget *dt)
	{
	return (struct xlib_displaytarget *) dt;
	}


	/**
	* X Shared Memory Image extension code
	*/

	static volatile int XErrorFlag = 0;

	/**
	* Catches potential Xlib errors.
	*/
	static int
	handle_xerror(Display dpy, XErrorEvent event)
	{
	(void) dpy;
	(void) event;
	XErrorFlag = 1;
	return 0;
	}


	static char *
	alloc_shm(struct xlib_displaytarget *buf, unsigned size)
	{
	XShmSegmentInfo *const shminfo = & buf->shminfo;

	shminfo->shmid = -1;
	shminfo->shmaddr = (char *) -1;

	shminfo->shmid = shmget(IPC_PRIVATE, size, IPC_CREAT\|0777);
	if (shminfo->shmid < 0) {
	return NULL;
	}

	shminfo->shmaddr = (char *) shmat(shminfo->shmid, 0, 0);
	if (shminfo->shmaddr == (char *) -1) {
	shmctl(shminfo->shmid, IPC_RMID, 0);
	return NULL;
	}

	shminfo->readOnly = False;
	return shminfo->shmaddr;
	}


	/**
	* Allocate a shared memory XImage back buffer for the given display target.
	*/
	static void
	alloc_shm_ximage(struct xlib_displaytarget *xlib_dt,
	struct xlib_drawable *xmb,
	unsigned width, unsigned height)
	{
	/*
	* We have to do a _lot_ of error checking here to be sure we can
	* really use the XSHM extension. It seems different servers trigger
	* errors at different points if the extension won't work. Therefore
	* we have to be very careful...
	*/
	int (old_handler)(Display , XErrorEvent *);

	xlib_dt->tempImage = XShmCreateImage(xlib_dt->display,
	xmb->visual,
	xmb->depth,
	ZPixmap,
	NULL,
	&xlib_dt->shminfo,
	width, height);
	if (xlib_dt->tempImage == NULL) {
	xlib_dt->shm = False;
	return;
	}


	XErrorFlag = 0;
	old_handler = XSetErrorHandler(handle_xerror);
	/* This may trigger the X protocol error we're ready to catch: */
	XShmAttach(xlib_dt->display, &xlib_dt->shminfo);
	XSync(xlib_dt->display, False);

	if (XErrorFlag) {
	/* we are on a remote display, this error is normal, don't print it */
	XFlush(xlib_dt->display);
	XErrorFlag = 0;
	XDestroyImage(xlib_dt->tempImage);
	xlib_dt->tempImage = NULL;
	xlib_dt->shm = False;
	(void) XSetErrorHandler(old_handler);
	return;
	}

	xlib_dt->shm = True;
	}


	static void
	alloc_ximage(struct xlib_displaytarget *xlib_dt,
	struct xlib_drawable *xmb,
	unsigned width, unsigned height)
	{
	/* try allocating a shared memory image first */
	if (xlib_dt->shm) {
	alloc_shm_ximage(xlib_dt, xmb, width, height);
	if (xlib_dt->tempImage)
	return; /* success */
	}

	/* try regular (non-shared memory) image */
	xlib_dt->tempImage = XCreateImage(xlib_dt->display,
	xmb->visual,
	xmb->depth,
	ZPixmap, 0,
	NULL, width, height,
	8, 0);
	}

	static boolean
	xlib_is_displaytarget_format_supported(struct sw_winsys *ws,
	unsigned tex_usage,
	enum pipe_format format)
	{
	/* TODO: check visuals or other sensible thing here */
	return TRUE;
	}


	static void *
	xlib_displaytarget_map(struct sw_winsys *ws,
	struct sw_displaytarget *dt,
	unsigned flags)
	{
	struct xlib_displaytarget *xlib_dt = xlib_displaytarget(dt);
	xlib_dt->mapped = xlib_dt->data;
	return xlib_dt->mapped;
	}


	static void
	xlib_displaytarget_unmap(struct sw_winsys *ws,
	struct sw_displaytarget *dt)
	{
	struct xlib_displaytarget *xlib_dt = xlib_displaytarget(dt);
	xlib_dt->mapped = NULL;
	}


	static void
	xlib_displaytarget_destroy(struct sw_winsys *ws,
	struct sw_displaytarget *dt)
	{
	struct xlib_displaytarget *xlib_dt = xlib_displaytarget(dt);

	if (xlib_dt->data) {
	if (xlib_dt->shminfo.shmid >= 0) {
	shmdt(xlib_dt->shminfo.shmaddr);
	shmctl(xlib_dt->shminfo.shmid, IPC_RMID, 0);

	xlib_dt->shminfo.shmid = -1;
	xlib_dt->shminfo.shmaddr = (char *) -1;

	xlib_dt->data = NULL;
	if (xlib_dt->tempImage)
	xlib_dt->tempImage->data = NULL;
	}
	else {
	FREE(xlib_dt->data);
	if (xlib_dt->tempImage && xlib_dt->tempImage->data == xlib_dt->data) {
	xlib_dt->tempImage->data = NULL;
	}
	xlib_dt->data = NULL;
	}
	}

	if (xlib_dt->tempImage) {
	XDestroyImage(xlib_dt->tempImage);
	xlib_dt->tempImage = NULL;
	}

	if (xlib_dt->gc)
	XFreeGC(xlib_dt->display, xlib_dt->gc);

	FREE(xlib_dt);
	}


	/**
	* Display/copy the image in the surface into the X window specified
	* by the display target.
	*/
	static void
	xlib_sw_display(struct xlib_drawable *xlib_drawable,
	struct sw_displaytarget *dt)
	{
	static boolean no_swap = 0;
	static boolean firsttime = 1;
	struct xlib_displaytarget *xlib_dt = xlib_displaytarget(dt);
	Display *display = xlib_dt->display;
	XImage *ximage;

	if (firsttime) {
	no_swap = getenv("SP_NO_RAST") != NULL;
	firsttime = 0;
	}

	if (no_swap)
	return;

	if (xlib_dt->drawable != xlib_drawable->drawable) {
	if (xlib_dt->gc) {
	XFreeGC(display, xlib_dt->gc);
	xlib_dt->gc = NULL;
	}

	if (xlib_dt->tempImage) {
	XDestroyImage(xlib_dt->tempImage);
	xlib_dt->tempImage = NULL;
	}

	xlib_dt->drawable = xlib_drawable->drawable;
	}

	if (xlib_dt->tempImage == NULL) {
	assert(util_format_get_blockwidth(xlib_dt->format) == 1);
	assert(util_format_get_blockheight(xlib_dt->format) == 1);
	alloc_ximage(xlib_dt, xlib_drawable,
	xlib_dt->stride / util_format_get_blocksize(xlib_dt->format),
	xlib_dt->height);
	if (!xlib_dt->tempImage)
	return;
	}

	if (xlib_dt->gc == NULL) {
	xlib_dt->gc = XCreateGC(display, xlib_drawable->drawable, 0, NULL);
	XSetFunction(display, xlib_dt->gc, GXcopy);
	}

	if (xlib_dt->shm) {
	ximage = xlib_dt->tempImage;
	ximage->data = xlib_dt->data;

	/* _debug_printf("XSHM\n"); */
	XShmPutImage(xlib_dt->display, xlib_drawable->drawable, xlib_dt->gc,
	ximage, 0, 0, 0, 0, xlib_dt->width, xlib_dt->height, False);
	}
	else {
	/* display image in Window */
	ximage = xlib_dt->tempImage;
	ximage->data = xlib_dt->data;

	/* check that the XImage has been previously initialized */
	assert(ximage->format);
	assert(ximage->bitmap_unit);

	/* update XImage's fields */
	ximage->width = xlib_dt->width;
	ximage->height = xlib_dt->height;
	ximage->bytes_per_line = xlib_dt->stride;

	/* _debug_printf("XPUT\n"); */
	XPutImage(xlib_dt->display, xlib_drawable->drawable, xlib_dt->gc,
	ximage, 0, 0, 0, 0, xlib_dt->width, xlib_dt->height);
	}

	XFlush(xlib_dt->display);
	}


	/**
	* Display/copy the image in the surface into the X window specified
	* by the display target.
	*/
	static void
	xlib_displaytarget_display(struct sw_winsys *ws,
	struct sw_displaytarget *dt,
	void *context_private)
	{
	struct xlib_drawable xlib_drawable = (struct xlib_drawable )context_private;
	xlib_sw_display(xlib_drawable, dt);
	}


	static struct sw_displaytarget *
	xlib_displaytarget_create(struct sw_winsys *winsys,
	unsigned tex_usage,
	enum pipe_format format,
	unsigned width, unsigned height,
	unsigned alignment,
	unsigned *stride)
	{
	struct xlib_displaytarget *xlib_dt;
	unsigned nblocksy, size;

	xlib_dt = CALLOC_STRUCT(xlib_displaytarget);
	if (!xlib_dt)
	goto no_xlib_dt;

	xlib_dt->display = ((struct xlib_sw_winsys *)winsys)->display;
	xlib_dt->format = format;
	xlib_dt->width = width;
	xlib_dt->height = height;

	nblocksy = util_format_get_nblocksy(format, height);
	xlib_dt->stride = align(util_format_get_stride(format, width), alignment);
	size = xlib_dt->stride * nblocksy;

	if (!debug_get_option_xlib_no_shm()) {
	xlib_dt->data = alloc_shm(xlib_dt, size);
	if (xlib_dt->data) {
	xlib_dt->shm = True;
	}
	}

	if (!xlib_dt->data) {
	xlib_dt->data = align_malloc(size, alignment);
	if (!xlib_dt->data)
	goto no_data;
	}

	*stride = xlib_dt->stride;
	return (struct sw_displaytarget *)xlib_dt;

	no_data:
	FREE(xlib_dt);
	no_xlib_dt:
	return NULL;
	}


	static struct sw_displaytarget *
	xlib_displaytarget_from_handle(struct sw_winsys *winsys,
	const struct pipe_resource *templet,
	struct winsys_handle *whandle,
	unsigned *stride)
	{
	assert(0);
	return NULL;
	}


	static boolean
	xlib_displaytarget_get_handle(struct sw_winsys *winsys,
	struct sw_displaytarget *dt,
	struct winsys_handle *whandle)
	{
	assert(0);
	return FALSE;
	}


	static void
	xlib_destroy(struct sw_winsys *ws)
	{
	FREE(ws);
	}


	struct sw_winsys *
	xlib_create_sw_winsys(Display *display)
	{
	struct xlib_sw_winsys *ws;

	ws = CALLOC_STRUCT(xlib_sw_winsys);
	if (!ws)
	return NULL;

	ws->display = display;
	ws->base.destroy = xlib_destroy;

	ws->base.is_displaytarget_format_supported = xlib_is_displaytarget_format_supported;

	ws->base.displaytarget_create = xlib_displaytarget_create;
	ws->base.displaytarget_from_handle = xlib_displaytarget_from_handle;
	ws->base.displaytarget_get_handle = xlib_displaytarget_get_handle;
	ws->base.displaytarget_map = xlib_displaytarget_map;
	ws->base.displaytarget_unmap = xlib_displaytarget_unmap;
	ws->base.displaytarget_destroy = xlib_displaytarget_destroy;

	ws->base.displaytarget_display = xlib_displaytarget_display;

	return &ws->base;
	}