softpipe: rework to use the llvmpipe winsys

Promote the llvmpipe winsys more or less unchanged to
state_trackers/sw_winsys.h.

Some minor breakages:
  - softpipe::texture_blanket is broken, but scheduled for removal anyway.
  - haven't fixed up g3vdl yet.

10 files changed, 451 insertions, 1184 deletions

diff --git a/src/gallium/winsys/gdi/SConscript b/src/gallium/winsys/gdi/SConscript
index 4cbc86f3311..4b32aa27e17 100644
--- a/src/gallium/winsys/gdi/SConscript
+++ b/src/gallium/winsys/gdi/SConscript
@@ -18,7 +18,7 @@ if env['platform'] == 'windows':
         'ws2_32',
     ])
 
-    sources = []
+    sources = ['gdi_sw_winsys.c']
     drivers = []
 
     if 'softpipe' in env['drivers']:
diff --git a/src/gallium/winsys/gdi/gdi_llvmpipe_winsys.c b/src/gallium/winsys/gdi/gdi_llvmpipe_winsys.c
index a9fa03b8e57..3d317c70dda 100644
--- a/src/gallium/winsys/gdi/gdi_llvmpipe_winsys.c
+++ b/src/gallium/winsys/gdi/gdi_llvmpipe_winsys.c
@@ -36,153 +36,8 @@
 
 #include <windows.h>
 
-#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 "llvmpipe/lp_winsys.h"
+#include "gdi_winsys.h"
 #include "llvmpipe/lp_texture.h"
-#include "stw_winsys.h"
-
-
-struct gdi_llvmpipe_displaytarget
-{
-   enum pipe_format format;
-   unsigned width;
-   unsigned height;
-   unsigned stride;
-
-   unsigned size;
-
-   void *data;
-
-   BITMAPINFO bmi;
-};
-
-
-/** Cast wrapper */
-static INLINE struct gdi_llvmpipe_displaytarget *
-gdi_llvmpipe_displaytarget( struct llvmpipe_displaytarget *buf )
-{
-   return (struct gdi_llvmpipe_displaytarget *)buf;
-}
-
-
-static boolean
-gdi_llvmpipe_is_displaytarget_format_supported( struct llvmpipe_winsys *ws,
-                                                enum pipe_format format )
-{
-   switch(format) {
-   case PIPE_FORMAT_B8G8R8X8_UNORM:
-   case PIPE_FORMAT_B8G8R8A8_UNORM:
-      return TRUE;
-
-   /* TODO: Support other formats possible with BMPs, as described in 
-    * http://msdn.microsoft.com/en-us/library/dd183376(VS.85).aspx */
-      
-   default:
-      return FALSE;
-   }
-}
-
-
-static void *
-gdi_llvmpipe_displaytarget_map(struct llvmpipe_winsys *ws,
-                               struct llvmpipe_displaytarget *dt,
-                               unsigned flags )
-{
-   struct gdi_llvmpipe_displaytarget *gdt = gdi_llvmpipe_displaytarget(dt);
-
-   return gdt->data;
-}
-
-
-static void
-gdi_llvmpipe_displaytarget_unmap(struct llvmpipe_winsys *ws,
-                                 struct llvmpipe_displaytarget *dt )
-{
-
-}
-
-
-static void
-gdi_llvmpipe_displaytarget_destroy(struct llvmpipe_winsys *winsys,
-                                   struct llvmpipe_displaytarget *dt)
-{
-   struct gdi_llvmpipe_displaytarget *gdt = gdi_llvmpipe_displaytarget(dt);
-
-   align_free(gdt->data);
-   FREE(gdt);
-}
-
-
-static struct llvmpipe_displaytarget *
-gdi_llvmpipe_displaytarget_create(struct llvmpipe_winsys *winsys,
-                                  enum pipe_format format,
-                                  unsigned width, unsigned height,
-                                  unsigned alignment,
-                                  unsigned *stride)
-{
-   struct gdi_llvmpipe_displaytarget *gdt;
-   unsigned cpp;
-   unsigned bpp;
-   
-   gdt = CALLOC_STRUCT(gdi_llvmpipe_displaytarget);
-   if(!gdt)
-      goto no_gdt;
-
-   gdt->format = format;
-   gdt->width = width;
-   gdt->height = height;
-
-   bpp = util_format_get_blocksizebits(format);
-   cpp = util_format_get_blocksize(format);
-   
-   gdt->stride = align(width * cpp, alignment);
-   gdt->size = gdt->stride * height;
-   
-   gdt->data = align_malloc(gdt->size, alignment);
-   if(!gdt->data)
-      goto no_data;
-
-   gdt->bmi.bmiHeader.biSize = sizeof(BITMAPINFOHEADER);
-   gdt->bmi.bmiHeader.biWidth = gdt->stride / cpp;
-   gdt->bmi.bmiHeader.biHeight= -(long)height;
-   gdt->bmi.bmiHeader.biPlanes = 1;
-   gdt->bmi.bmiHeader.biBitCount = bpp;
-   gdt->bmi.bmiHeader.biCompression = BI_RGB;
-   gdt->bmi.bmiHeader.biSizeImage = 0;
-   gdt->bmi.bmiHeader.biXPelsPerMeter = 0;
-   gdt->bmi.bmiHeader.biYPelsPerMeter = 0;
-   gdt->bmi.bmiHeader.biClrUsed = 0;
-   gdt->bmi.bmiHeader.biClrImportant = 0;
-
-   *stride = gdt->stride;
-   return (struct llvmpipe_displaytarget *)gdt;
-
-no_data:
-   FREE(gdt);
-no_gdt:
-   return NULL;
-}
-
-
-static void
-gdi_llvmpipe_displaytarget_display(struct llvmpipe_winsys *winsys, 
-                                   struct llvmpipe_displaytarget *dt,
-                                   void *context_private)
-{
-   assert(0);
-}
-
-
-static void
-gdi_llvmpipe_destroy(struct llvmpipe_winsys *winsys)
-{
-   FREE(winsys);
-}
 
 
 static struct pipe_screen *
@@ -191,18 +46,10 @@ gdi_llvmpipe_screen_create(void)
    static struct llvmpipe_winsys *winsys;
    struct pipe_screen *screen;
 
-   winsys = CALLOC_STRUCT(llvmpipe_winsys);
+   winsys = gdi_create_sw_winsys();
    if(!winsys)
       goto no_winsys;
 
-   winsys->destroy = gdi_llvmpipe_destroy;
-   winsys->is_displaytarget_format_supported = gdi_llvmpipe_is_displaytarget_format_supported;
-   winsys->displaytarget_create = gdi_llvmpipe_displaytarget_create;
-   winsys->displaytarget_map = gdi_llvmpipe_displaytarget_map;
-   winsys->displaytarget_unmap = gdi_llvmpipe_displaytarget_unmap;
-   winsys->displaytarget_display = gdi_llvmpipe_displaytarget_display;
-   winsys->displaytarget_destroy = gdi_llvmpipe_displaytarget_destroy;
-
    screen = llvmpipe_create_screen(winsys);
    if(!screen)
       goto no_screen;
diff --git a/src/gallium/winsys/gdi/gdi_softpipe_winsys.c b/src/gallium/winsys/gdi/gdi_softpipe_winsys.c
index 71360e55aac..56e84fd0662 100644
--- a/src/gallium/winsys/gdi/gdi_softpipe_winsys.c
+++ b/src/gallium/winsys/gdi/gdi_softpipe_winsys.c
@@ -1,6 +1,6 @@
 /**************************************************************************
  *
- * Copyright 2008 Tungsten Graphics, Inc., Bismarck, ND., USA
+ * Copyright 2009 VMware, Inc.
  * All Rights Reserved.
  *
  * Permission is hereby granted, free of charge, to any person obtaining a
@@ -28,257 +28,58 @@
 
 /**
  * @file
- * Softpipe support.
+ * LLVMpipe support.
  *
- * @author Keith Whitwell
- * @author Brian Paul
- * @author Jose Fonseca
+ * @author Jose Fonseca <[email protected]>
  */
 
 
 #include <windows.h>
 
-#include "util/u_simple_screen.h"
-#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 "softpipe/sp_winsys.h"
+#include "gdi_winsys.h"
 #include "softpipe/sp_texture.h"
-#include "stw_winsys.h"
-
-
-struct gdi_softpipe_buffer
-{
-   struct pipe_buffer base;
-   boolean userBuffer;  /** Is this a user-space buffer? */
-   void *data;
-   void *mapped;
-};
-
-
-/** Cast wrapper */
-static INLINE struct gdi_softpipe_buffer *
-gdi_softpipe_buffer( struct pipe_buffer *buf )
-{
-   return (struct gdi_softpipe_buffer *)buf;
-}
-
-
-static void *
-gdi_softpipe_buffer_map(struct pipe_winsys *winsys,
-                        struct pipe_buffer *buf,
-                        unsigned flags)
-{
-   struct gdi_softpipe_buffer *gdi_softpipe_buf = gdi_softpipe_buffer(buf);
-   gdi_softpipe_buf->mapped = gdi_softpipe_buf->data;
-   return gdi_softpipe_buf->mapped;
-}
-
-
-static void
-gdi_softpipe_buffer_unmap(struct pipe_winsys *winsys,
-                          struct pipe_buffer *buf)
-{
-   struct gdi_softpipe_buffer *gdi_softpipe_buf = gdi_softpipe_buffer(buf);
-   gdi_softpipe_buf->mapped = NULL;
-}
-
-
-static void
-gdi_softpipe_buffer_destroy(struct pipe_buffer *buf)
-{
-   struct gdi_softpipe_buffer *oldBuf = gdi_softpipe_buffer(buf);
-
-   if (oldBuf->data) {
-      if (!oldBuf->userBuffer)
-         align_free(oldBuf->data);
-
-      oldBuf->data = NULL;
-   }
-
-   FREE(oldBuf);
-}
-
-
-static const char *
-gdi_softpipe_get_name(struct pipe_winsys *winsys)
-{
-   return "softpipe";
-}
-
-
-static struct pipe_buffer *
-gdi_softpipe_buffer_create(struct pipe_winsys *winsys,
-                           unsigned alignment,
-                           unsigned usage,
-                           unsigned size)
-{
-   struct gdi_softpipe_buffer *buffer = CALLOC_STRUCT(gdi_softpipe_buffer);
-
-   pipe_reference_init(&buffer->base.reference, 1);
-   buffer->base.alignment = alignment;
-   buffer->base.usage = usage;
-   buffer->base.size = size;
-
-   buffer->data = align_malloc(size, alignment);
-
-   return &buffer->base;
-}
-
-
-/**
- * Create buffer which wraps user-space data.
- */
-static struct pipe_buffer *
-gdi_softpipe_user_buffer_create(struct pipe_winsys *winsys,
-                               void *ptr,
-                               unsigned bytes)
-{
-   struct gdi_softpipe_buffer *buffer;
-
-   buffer = CALLOC_STRUCT(gdi_softpipe_buffer);
-   if(!buffer)
-      return NULL;
-
-   pipe_reference_init(&buffer->base.reference, 1);
-   buffer->base.size = bytes;
-   buffer->userBuffer = TRUE;
-   buffer->data = ptr;
-
-   return &buffer->base;
-}
-
-
-static struct pipe_buffer *
-gdi_softpipe_surface_buffer_create(struct pipe_winsys *winsys,
-                                   unsigned width, unsigned height,
-                                   enum pipe_format format,
-                                   unsigned usage,
-                                   unsigned tex_usage,
-                                   unsigned *stride)
-{
-   const unsigned alignment = 64;
-   unsigned nblocksy;
-
-   nblocksy = util_format_get_nblocksy(format, height);
-   *stride = align(util_format_get_stride(format, width), alignment);
-
-   return winsys->buffer_create(winsys, alignment,
-                                usage,
-                                *stride * nblocksy);
-}
-
-
-static void
-gdi_softpipe_dummy_flush_frontbuffer(struct pipe_winsys *winsys,
-                                     struct pipe_surface *surface,
-                                     void *context_private)
-{
-   assert(0);
-}
-
-
-static void
-gdi_softpipe_fence_reference(struct pipe_winsys *winsys,
-                             struct pipe_fence_handle **ptr,
-                             struct pipe_fence_handle *fence)
-{
-}
-
-
-static int
-gdi_softpipe_fence_signalled(struct pipe_winsys *winsys,
-                             struct pipe_fence_handle *fence,
-                             unsigned flag)
-{
-   return 0;
-}
-
-
-static int
-gdi_softpipe_fence_finish(struct pipe_winsys *winsys,
-                          struct pipe_fence_handle *fence,
-                          unsigned flag)
-{
-   return 0;
-}
-
-
-static void
-gdi_softpipe_destroy(struct pipe_winsys *winsys)
-{
-   FREE(winsys);
-}
 
 
 static struct pipe_screen *
 gdi_softpipe_screen_create(void)
 {
-   static struct pipe_winsys *winsys;
+   static struct softpipe_winsys *winsys;
    struct pipe_screen *screen;
 
-   winsys = CALLOC_STRUCT(pipe_winsys);
+   winsys = gdi_create_sw_winsys();
    if(!winsys)
-      return NULL;
-
-   winsys->destroy = gdi_softpipe_destroy;
-
-   winsys->buffer_create = gdi_softpipe_buffer_create;
-   winsys->user_buffer_create = gdi_softpipe_user_buffer_create;
-   winsys->buffer_map = gdi_softpipe_buffer_map;
-   winsys->buffer_unmap = gdi_softpipe_buffer_unmap;
-   winsys->buffer_destroy = gdi_softpipe_buffer_destroy;
-
-   winsys->surface_buffer_create = gdi_softpipe_surface_buffer_create;
-
-   winsys->fence_reference = gdi_softpipe_fence_reference;
-   winsys->fence_signalled = gdi_softpipe_fence_signalled;
-   winsys->fence_finish = gdi_softpipe_fence_finish;
-
-   winsys->flush_frontbuffer = gdi_softpipe_dummy_flush_frontbuffer;
-   winsys->get_name = gdi_softpipe_get_name;
+      goto no_winsys;
 
    screen = softpipe_create_screen(winsys);
    if(!screen)
-      gdi_softpipe_destroy(winsys);
+      goto no_screen;
 
    return screen;
+   
+no_screen:
+   FREE(winsys);
+no_winsys:
+   return NULL;
 }
 
 
+
+
 static void
 gdi_softpipe_present(struct pipe_screen *screen,
                      struct pipe_surface *surface,
                      HDC hDC)
 {
     struct softpipe_texture *texture;
-    struct gdi_softpipe_buffer *buffer;
-    BITMAPINFO bmi;
+    struct gdi_softpipe_displaytarget *gdt;
 
     texture = softpipe_texture(surface->texture);
-                                               
-    buffer = gdi_softpipe_buffer(texture->buffer);
-
-    memset(&bmi, 0, sizeof(BITMAPINFO));
-    bmi.bmiHeader.biSize = sizeof(BITMAPINFOHEADER);
-    bmi.bmiHeader.biWidth = texture->stride[surface->level] / util_format_get_blocksize(surface->format);
-    bmi.bmiHeader.biHeight= -(long)surface->height;
-    bmi.bmiHeader.biPlanes = 1;
-    bmi.bmiHeader.biBitCount = util_format_get_blocksizebits(surface->format);
-    bmi.bmiHeader.biCompression = BI_RGB;
-    bmi.bmiHeader.biSizeImage = 0;
-    bmi.bmiHeader.biXPelsPerMeter = 0;
-    bmi.bmiHeader.biYPelsPerMeter = 0;
-    bmi.bmiHeader.biClrUsed = 0;
-    bmi.bmiHeader.biClrImportant = 0;
+    gdt = gdi_softpipe_displaytarget(texture->dt);
 
     StretchDIBits(hDC,
-                  0, 0, surface->width, surface->height,
-                  0, 0, surface->width, surface->height,
-                  buffer->data, &bmi, 0, SRCCOPY);
+                  0, 0, gdt->width, gdt->height,
+                  0, 0, gdt->width, gdt->height,
+                  gdt->data, &gdt->bmi, 0, SRCCOPY);
 }
 
 
diff --git a/src/gallium/winsys/xlib/Makefile b/src/gallium/winsys/xlib/Makefile
index 824c666ae30..129300423a6 100644
--- a/src/gallium/winsys/xlib/Makefile
+++ b/src/gallium/winsys/xlib/Makefile
@@ -29,6 +29,7 @@ DEFINES += \
 XLIB_WINSYS_SOURCES = \
 	xlib.c \
 	xlib_cell.c \
+	xlib_sw_winsys.c \
 	xlib_llvmpipe.c \
 	xlib_softpipe.c
 
diff --git a/src/gallium/winsys/xlib/SConscript b/src/gallium/winsys/xlib/SConscript
index 8c9d318af2b..92e508ee50c 100644
--- a/src/gallium/winsys/xlib/SConscript
+++ b/src/gallium/winsys/xlib/SConscript
@@ -36,7 +36,7 @@ drivers = [trace]
     
 if 'softpipe' in env['drivers']:
     env.Append(CPPDEFINES = 'GALLIUM_SOFTPIPE')
-    sources += ['xlib_softpipe.c']
+    sources += ['xlib_softpipe.c', 'xlib_sw_winsys.c']
     drivers += [softpipe]
 
 if 'llvmpipe' in env['drivers']:
@@ -44,7 +44,7 @@ if 'llvmpipe' in env['drivers']:
     if 'LLVM_VERSION' in env:
         env.Append(CPPDEFINES = 'GALLIUM_LLVMPIPE')
         env.Tool('udis86')
-        sources += ['xlib_llvmpipe.c']
+        sources += ['xlib_llvmpipe.c', 'xlib_sw_winsys.c']
         drivers += [llvmpipe]
     
 if 'cell' in env['drivers']:
diff --git a/src/gallium/winsys/xlib/xlib.c b/src/gallium/winsys/xlib/xlib.c
index 67617a470d6..9b91c980d15 100644
--- a/src/gallium/winsys/xlib/xlib.c
+++ b/src/gallium/winsys/xlib/xlib.c
@@ -33,9 +33,7 @@
 
 #include "xlib.h"
 #include "xm_winsys.h"
-
-#include <stdlib.h>
-#include <assert.h>
+#include "util/u_debug.h"
 
 /* Todo, replace all this with callback-structs provided by the
  * individual implementations.
diff --git a/src/gallium/winsys/xlib/xlib.h b/src/gallium/winsys/xlib/xlib.h
index 8e091d0c084..7f9f910b88d 100644
--- a/src/gallium/winsys/xlib/xlib.h
+++ b/src/gallium/winsys/xlib/xlib.h
@@ -9,5 +9,12 @@ extern struct xm_driver xlib_softpipe_driver;
 extern struct xm_driver xlib_llvmpipe_driver;
 extern struct xm_driver xlib_cell_driver;
 
+/* Internal:
+ */
+struct sw_winsys;
+struct sw_displaytarget;
+struct sw_winsys *xlib_create_sw_winsys( void );
+void xlib_sw_display(struct xmesa_buffer *xm_buffer,
+                     struct sw_displaytarget *dt);
 
 #endif
diff --git a/src/gallium/winsys/xlib/xlib_llvmpipe.c b/src/gallium/winsys/xlib/xlib_llvmpipe.c
index 6cebd4c2012..9929ba52e73 100644
--- a/src/gallium/winsys/xlib/xlib_llvmpipe.c
+++ b/src/gallium/winsys/xlib/xlib_llvmpipe.c
@@ -33,367 +33,16 @@
  */
 
 
-#if defined(GALLIUM_LLVMPIPE)
-
-#include "xm_api.h"
 
-#undef ASSERT
-#undef Elements
-
-#include "util/u_simple_screen.h"
-#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 "llvmpipe/lp_winsys.h"
-#include "llvmpipe/lp_texture.h"
 
 #include "xlib.h"
 
-/**
- * Subclass of pipe_buffer for Xlib winsys.
- * Low-level OS/window system memory buffer
- */
-struct xm_displaytarget
-{
-   enum pipe_format format;
-   unsigned width;
-   unsigned height;
-   unsigned stride;
-
-   void *data;
-   void *mapped;
-
-   XImage *tempImage;
-#ifdef USE_XSHM
-   int shm;
-   XShmSegmentInfo shminfo;
-#endif
-};
-
-
-/**
- * Subclass of llvmpipe_winsys for Xlib winsys
- */
-struct xmesa_llvmpipe_winsys
-{
-   struct llvmpipe_winsys base;
-/*   struct xmesa_visual *xm_visual; */
-};
-
-
-
-/** Cast wrapper */
-static INLINE struct xm_displaytarget *
-xm_displaytarget( struct llvmpipe_displaytarget *dt )
-{
-   return (struct xm_displaytarget *)dt;
-}
-
-
-/**
- * X Shared Memory Image extension code
- */
-
-#ifdef USE_XSHM
-
-static volatile int mesaXErrorFlag = 0;
-
-/**
- * Catches potential Xlib errors.
- */
-static int
-mesaHandleXError(Display *dpy, XErrorEvent *event)
-{
-   (void) dpy;
-   (void) event;
-   mesaXErrorFlag = 1;
-   return 0;
-}
-
-
-static char *alloc_shm(struct xm_displaytarget *buf, unsigned size)
-{
-   XShmSegmentInfo *const shminfo = & buf->shminfo;
-
-   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 XMesaBuffer.
- */
-static void
-alloc_shm_ximage(struct xm_displaytarget *xm_buffer,
-                 struct xmesa_buffer *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 *);
-
-   xm_buffer->tempImage = XShmCreateImage(xmb->xm_visual->display,
-                                  xmb->xm_visual->visinfo->visual,
-                                  xmb->xm_visual->visinfo->depth,
-                                  ZPixmap,
-                                  NULL,
-                                  &xm_buffer->shminfo,
-                                  width, height);
-   if (xm_buffer->tempImage == NULL) {
-      xm_buffer->shm = 0;
-      return;
-   }
-
-
-   mesaXErrorFlag = 0;
-   old_handler = XSetErrorHandler(mesaHandleXError);
-   /* This may trigger the X protocol error we're ready to catch: */
-   XShmAttach(xmb->xm_visual->display, &xm_buffer->shminfo);
-   XSync(xmb->xm_visual->display, False);
-
-   if (mesaXErrorFlag) {
-      /* we are on a remote display, this error is normal, don't print it */
-      XFlush(xmb->xm_visual->display);
-      mesaXErrorFlag = 0;
-      XDestroyImage(xm_buffer->tempImage);
-      xm_buffer->tempImage = NULL;
-      xm_buffer->shm = 0;
-      (void) XSetErrorHandler(old_handler);
-      return;
-   }
-
-   xm_buffer->shm = 1;
-}
-
-#endif /* USE_XSHM */
-
-static boolean
-xm_is_displaytarget_format_supported( struct llvmpipe_winsys *ws,
-                                      enum pipe_format format )
-{
-   /* TODO: check visuals or other sensible thing here */
-   return TRUE;
-}
-
-
-static void *
-xm_displaytarget_map(struct llvmpipe_winsys *ws,
-                     struct llvmpipe_displaytarget *dt,
-                     unsigned flags)
-{
-   struct xm_displaytarget *xm_dt = xm_displaytarget(dt);
-   xm_dt->mapped = xm_dt->data;
-   return xm_dt->mapped;
-}
-
-static void
-xm_displaytarget_unmap(struct llvmpipe_winsys *ws,
-                       struct llvmpipe_displaytarget *dt)
-{
-   struct xm_displaytarget *xm_dt = xm_displaytarget(dt);
-   xm_dt->mapped = NULL;
-}
-
-static void
-xm_displaytarget_destroy(struct llvmpipe_winsys *ws,
-                         struct llvmpipe_displaytarget *dt)
-{
-   struct xm_displaytarget *xm_dt = xm_displaytarget(dt);
-
-   if (xm_dt->data) {
-#ifdef USE_XSHM
-      if (xm_dt->shminfo.shmid >= 0) {
-         shmdt(xm_dt->shminfo.shmaddr);
-         shmctl(xm_dt->shminfo.shmid, IPC_RMID, 0);
-         
-         xm_dt->shminfo.shmid = -1;
-         xm_dt->shminfo.shmaddr = (char *) -1;
-      }
-      else
-#endif
-         FREE(xm_dt->data);
-   }
-
-   FREE(xm_dt);
-}
-
-
-/**
- * Display/copy the image in the surface into the X window specified
- * by the XMesaBuffer.
- */
-static void
-xm_llvmpipe_display(struct xmesa_buffer *xm_buffer,
-                    struct llvmpipe_displaytarget *dt)
-{
-   XImage *ximage;
-   struct xm_displaytarget *xm_dt = xm_displaytarget(dt);
-   static boolean no_swap = 0;
-   static boolean firsttime = 1;
-
-   if (firsttime) {
-      no_swap = getenv("SP_NO_RAST") != NULL;
-      firsttime = 0;
-   }
-
-   if (no_swap)
-      return;
-
-#ifdef USE_XSHM
-   if (xm_dt->shm)
-   {
-      if (xm_dt->tempImage == NULL)
-      {
-         assert(util_format_get_blockwidth(xm_dt->format) == 1);
-         assert(util_format_get_blockheight(xm_dt->format) == 1);
-         alloc_shm_ximage(xm_dt, xm_buffer,
-                          xm_dt->stride / util_format_get_blocksize(xm_dt->format),
-                          xm_dt->height);
-      }
-
-      ximage = xm_dt->tempImage;
-      ximage->data = xm_dt->data;
-
-      /* _debug_printf("XSHM\n"); */
-      XShmPutImage(xm_buffer->xm_visual->display, xm_buffer->drawable, xm_buffer->gc,
-                   ximage, 0, 0, 0, 0, xm_dt->width, xm_dt->height, False);
-   }
-   else
-#endif
-   {
-      /* display image in Window */
-      ximage = xm_dt->tempImage;
-      ximage->data = xm_dt->data;
-
-      /* check that the XImage has been previously initialized */
-      assert(ximage->format);
-      assert(ximage->bitmap_unit);
-
-      /* update XImage's fields */
-      ximage->width = xm_dt->width;
-      ximage->height = xm_dt->height;
-      ximage->bytes_per_line = xm_dt->stride;
-
-      /* _debug_printf("XPUT\n"); */
-      XPutImage(xm_buffer->xm_visual->display, xm_buffer->drawable, xm_buffer->gc,
-                ximage, 0, 0, 0, 0, xm_dt->width, xm_dt->height);
-   }
-}
-
-/**
- * Display/copy the image in the surface into the X window specified
- * by the XMesaBuffer.
- */
-static void
-xm_displaytarget_display(struct llvmpipe_winsys *ws,
-                         struct llvmpipe_displaytarget *dt,
-                         void *context_private)
-{
-   XMesaContext xmctx = (XMesaContext) context_private;
-   struct xmesa_buffer *xm_buffer = xmctx->xm_buffer;
-   xm_llvmpipe_display(xm_buffer, dt);
-}
-
 
-static struct llvmpipe_displaytarget *
-xm_displaytarget_create(struct llvmpipe_winsys *winsys,
-                        enum pipe_format format,
-                        unsigned width, unsigned height,
-                        unsigned alignment,
-                        unsigned *stride)
-{
-   struct xm_displaytarget *xm_dt = CALLOC_STRUCT(xm_displaytarget);
-   unsigned nblocksy, size;
-
-   xm_dt = CALLOC_STRUCT(xm_displaytarget);
-   if(!xm_dt)
-      goto no_xm_dt;
-
-   xm_dt->format = format;
-   xm_dt->width = width;
-   xm_dt->height = height;
-
-   nblocksy = util_format_get_nblocksy(format, height);
-   xm_dt->stride = align(util_format_get_stride(format, width), alignment);
-   size = xm_dt->stride * nblocksy;
-
-#ifdef USE_XSHM
-   if (!debug_get_bool_option("XLIB_NO_SHM", FALSE))
-   {
-      xm_dt->shminfo.shmid = -1;
-      xm_dt->shminfo.shmaddr = (char *) -1;
-      xm_dt->shm = TRUE;
-         
-      xm_dt->data = alloc_shm(xm_dt, size);
-      if(!xm_dt->data)
-         goto no_data;
-   }
-#endif
-
-   if(!xm_dt->data) {
-      xm_dt->data = align_malloc(size, alignment);
-      if(!xm_dt->data)
-         goto no_data;
-   }
-
-   *stride = xm_dt->stride;
-   return (struct llvmpipe_displaytarget *)xm_dt;
-
-no_data:
-   FREE(xm_dt);
-no_xm_dt:
-   return NULL;
-}
-
-
-static void
-xm_destroy( struct llvmpipe_winsys *ws )
-{
-   FREE(ws);
-}
-
-
-static struct llvmpipe_winsys *
-xlib_create_llvmpipe_winsys( void )
-{
-   struct xmesa_llvmpipe_winsys *ws;
-
-   ws = CALLOC_STRUCT(xmesa_llvmpipe_winsys);
-   if (!ws)
-      return NULL;
-
-   ws->base.destroy = xm_destroy;
-
-   ws->base.is_displaytarget_format_supported = xm_is_displaytarget_format_supported;
-
-   ws->base.displaytarget_create = xm_displaytarget_create;
-   ws->base.displaytarget_map = xm_displaytarget_map;
-   ws->base.displaytarget_unmap = xm_displaytarget_unmap;
-   ws->base.displaytarget_destroy = xm_displaytarget_destroy;
-
-   ws->base.displaytarget_display = xm_displaytarget_display;
-
-   return &ws->base;
-}
+#if defined(GALLIUM_LLVMPIPE)
 
+#include "llvmpipe/lp_texture.h"
+#include "llvmpipe/lp_winsys.h"
+#include "state_tracker/sw_winsys.h"
 
 static struct pipe_screen *
 xlib_create_llvmpipe_screen( void )
@@ -401,7 +50,7 @@ xlib_create_llvmpipe_screen( void )
    struct llvmpipe_winsys *winsys;
    struct pipe_screen *screen;
 
-   winsys = xlib_create_llvmpipe_winsys();
+   winsys = xlib_create_sw_winsys();
    if (winsys == NULL)
       return NULL;
 
@@ -427,7 +76,7 @@ xlib_llvmpipe_display_surface(struct xmesa_buffer *xm_buffer,
 
    assert(texture->dt);
    if (texture->dt)
-      xm_llvmpipe_display(xm_buffer, texture->dt);
+      xlib_sw_display(xm_buffer, texture->dt);
 }
 
 
diff --git a/src/gallium/winsys/xlib/xlib_softpipe.c b/src/gallium/winsys/xlib/xlib_softpipe.c
index 716338aef47..df93de551cc 100644
--- a/src/gallium/winsys/xlib/xlib_softpipe.c
+++ b/src/gallium/winsys/xlib/xlib_softpipe.c
@@ -26,461 +26,19 @@
  * 
  **************************************************************************/
 
-/*
- * Authors:
- *   Keith Whitwell
- *   Brian Paul
- */
-
-
-#include "xm_api.h"
-
-#undef ASSERT
-#undef Elements
-
-#include "util/u_simple_screen.h"
-#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 "softpipe/sp_winsys.h"
-#include "softpipe/sp_texture.h"
 
 #include "xlib.h"
-
-/**
- * Subclass of pipe_buffer for Xlib winsys.
- * Low-level OS/window system memory buffer
- */
-struct xm_buffer
-{
-   struct pipe_buffer base;
-   boolean userBuffer;  /** Is this a user-space buffer? */
-   void *data;
-   void *mapped;
-
-   XImage *tempImage;
-#ifdef USE_XSHM
-   boolean shm;         /** Is this a shared memory buffer? */
-   XShmSegmentInfo shminfo;
-#endif
-};
-
-
-/**
- * Subclass of pipe_winsys for Xlib winsys
- */
-struct xmesa_pipe_winsys
-{
-   struct pipe_winsys base;
-/*   struct xmesa_visual *xm_visual; */
-};
-
-
-
-/** Cast wrapper */
-static INLINE struct xm_buffer *
-xm_buffer( struct pipe_buffer *buf )
-{
-   return (struct xm_buffer *)buf;
-}
-
-
-/**
- * X Shared Memory Image extension code
- */
-
-#ifdef USE_XSHM
-
-static volatile int mesaXErrorFlag = 0;
-
-/**
- * Catches potential Xlib errors.
- */
-static int
-mesaHandleXError(Display *dpy, XErrorEvent *event)
-{
-   (void) dpy;
-   (void) event;
-   mesaXErrorFlag = 1;
-   return 0;
-}
-
-
-static char *alloc_shm(struct xm_buffer *buf, unsigned size)
-{
-   XShmSegmentInfo *const shminfo = & buf->shminfo;
-
-   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 XMesaBuffer.
- */
-static void
-alloc_shm_ximage(struct xm_buffer *b, struct xmesa_buffer *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 *);
-
-   b->tempImage = XShmCreateImage(xmb->xm_visual->display,
-                                  xmb->xm_visual->visinfo->visual,
-                                  xmb->xm_visual->visinfo->depth,
-                                  ZPixmap,
-                                  NULL,
-                                  &b->shminfo,
-                                  width, height);
-   if (b->tempImage == NULL) {
-      b->shm = FALSE;
-      return;
-   }
-
-
-   mesaXErrorFlag = 0;
-   old_handler = XSetErrorHandler(mesaHandleXError);
-   /* This may trigger the X protocol error we're ready to catch: */
-   XShmAttach(xmb->xm_visual->display, &b->shminfo);
-   XSync(xmb->xm_visual->display, False);
-
-   if (mesaXErrorFlag) {
-      /* we are on a remote display, this error is normal, don't print it */
-      XFlush(xmb->xm_visual->display);
-      mesaXErrorFlag = 0;
-      XDestroyImage(b->tempImage);
-      b->tempImage = NULL;
-      b->shm = FALSE;
-      (void) XSetErrorHandler(old_handler);
-      return;
-   }
-
-   b->shm = TRUE;
-}
-
-#endif /* USE_XSHM */
-
-
-
-/* Most callbacks map direcly onto dri_bufmgr operations:
- */
-static void *
-xm_buffer_map(struct pipe_winsys *pws, struct pipe_buffer *buf,
-              unsigned flags)
-{
-   struct xm_buffer *xm_buf = xm_buffer(buf);
-   xm_buf->mapped = xm_buf->data;
-   return xm_buf->mapped;
-}
-
-static void
-xm_buffer_unmap(struct pipe_winsys *pws, struct pipe_buffer *buf)
-{
-   struct xm_buffer *xm_buf = xm_buffer(buf);
-   xm_buf->mapped = NULL;
-}
-
-static void
-xm_buffer_destroy(struct pipe_buffer *buf)
-{
-   struct xm_buffer *oldBuf = xm_buffer(buf);
-
-   /*
-    * Note oldBuf->data may point to one of three things:
-    * 1. XShm shared memory image data
-    * 2. User-provided (wrapped) memory, see xm_user_buffer_create()
-    * 3. Regular, malloc'd memory
-    * We need to be careful with freeing that data now.
-    */
-
-   if (oldBuf->data) {
-#ifdef USE_XSHM
-      if (oldBuf->shminfo.shmid >= 0) {
-         shmdt(oldBuf->shminfo.shmaddr);
-         shmctl(oldBuf->shminfo.shmid, IPC_RMID, 0);
-         
-         oldBuf->shminfo.shmid = -1;
-         oldBuf->shminfo.shmaddr = (char *) -1;
-      }
-
-      if (oldBuf->shm) {
-         oldBuf->data = NULL;
-      }
-
-      if (oldBuf->tempImage) {
-         XDestroyImage(oldBuf->tempImage);
-         oldBuf->tempImage = NULL;
-      }
-#endif
-
-      if (oldBuf->data && !oldBuf->userBuffer) {
-         /* this was regular malloc'd memory */
-         align_free(oldBuf->data);
-      }
-
-      oldBuf->data = NULL;
-   }
-
-   free(oldBuf);
-}
-
-
-/**
- * Display/copy the image in the surface into the X window specified
- * by the XMesaBuffer.
- */
-static void
-xlib_softpipe_display_surface(struct xmesa_buffer *b,
-                              struct pipe_surface *surf)
-{
-   XImage *ximage;
-   struct softpipe_texture *spt = softpipe_texture(surf->texture);
-   struct xm_buffer *xm_buf = xm_buffer(spt->buffer);
-   static boolean no_swap = 0;
-   static boolean firsttime = 1;
-
-   if (firsttime) {
-      no_swap = getenv("SP_NO_RAST") != NULL;
-      firsttime = 0;
-   }
-
-   if (no_swap)
-      return;
-
-#ifdef USE_XSHM
-   if (xm_buf->shm)
-   {
-      if (xm_buf->tempImage == NULL) 
-      {
-         assert(util_format_get_blockwidth(surf->texture->format) == 1);
-         assert(util_format_get_blockheight(surf->texture->format) == 1);
-         alloc_shm_ximage(xm_buf, b, spt->stride[surf->level] /
-                          util_format_get_blocksize(surf->texture->format), surf->height);
-      }
-
-      ximage = xm_buf->tempImage;
-      ximage->data = xm_buf->data;
-
-      /* _debug_printf("XSHM\n"); */
-      XShmPutImage(b->xm_visual->display, b->drawable, b->gc,
-                   ximage, 0, 0, 0, 0, surf->width, surf->height, False);
-   }
-   else
-#endif
-   {
-      /* display image in Window */
-      ximage = b->tempImage;
-      ximage->data = xm_buf->data;
-
-      /* check that the XImage has been previously initialized */
-      assert(ximage->format);
-      assert(ximage->bitmap_unit);
-
-      /* update XImage's fields */
-      ximage->width = surf->width;
-      ximage->height = surf->height;
-      ximage->bytes_per_line = spt->stride[surf->level];
-
-      /* _debug_printf("XPUT\n"); */
-      XPutImage(b->xm_visual->display, b->drawable, b->gc,
-                ximage, 0, 0, 0, 0, surf->width, surf->height);
-   }
-}
-
-
-static void
-xm_flush_frontbuffer(struct pipe_winsys *pws,
-                     struct pipe_surface *surf,
-                     void *context_private)
-{
-   /*
-    * The front color buffer is actually just another XImage buffer.
-    * This function copies that XImage to the actual X Window.
-    */
-   XMesaContext xmctx = (XMesaContext) context_private;
-   xlib_softpipe_display_surface(xmctx->xm_buffer, surf);
-   xmesa_check_and_update_buffer_size(xmctx, xmctx->xm_buffer);
-}
-
-
-
-static const char *
-xm_get_name(struct pipe_winsys *pws)
-{
-   return "Xlib";
-}
-
-
-static struct pipe_buffer *
-xm_buffer_create(struct pipe_winsys *pws, 
-                 unsigned alignment, 
-                 unsigned usage,
-                 unsigned size)
-{
-   struct xm_buffer *buffer = CALLOC_STRUCT(xm_buffer);
-
-   pipe_reference_init(&buffer->base.reference, 1);
-   buffer->base.alignment = alignment;
-   buffer->base.usage = usage;
-   buffer->base.size = size;
-
-   /* align to 16-byte multiple for Cell */
-   buffer->data = align_malloc(size, max(alignment, 16));
-
-   return &buffer->base;
-}
-
-
-/**
- * Create buffer which wraps user-space data.
- */
-static struct pipe_buffer *
-xm_user_buffer_create(struct pipe_winsys *pws, void *ptr, unsigned bytes)
-{
-   struct xm_buffer *buffer = CALLOC_STRUCT(xm_buffer);
-   pipe_reference_init(&buffer->base.reference, 1);
-   buffer->base.size = bytes;
-   buffer->userBuffer = TRUE;
-   buffer->data = ptr;
-
-   return &buffer->base;
-}
-
-
-static struct pipe_buffer *
-xm_surface_buffer_create(struct pipe_winsys *winsys,
-                         unsigned width, unsigned height,
-                         enum pipe_format format,
-                         unsigned usage,
-                         unsigned tex_usage,
-                         unsigned *stride)
-{
-   const unsigned alignment = 64;
-   unsigned nblocksy, size;
-
-   nblocksy = util_format_get_nblocksy(format, height);
-   *stride = align(util_format_get_stride(format, width), alignment);
-   size = *stride * nblocksy;
-
-#ifdef USE_XSHM
-   if (!debug_get_bool_option("XLIB_NO_SHM", FALSE))
-   {
-      struct xm_buffer *buffer = CALLOC_STRUCT(xm_buffer);
-
-      pipe_reference_init(&buffer->base.reference, 1);
-      buffer->base.alignment = alignment;
-      buffer->base.usage = usage;
-      buffer->base.size = size;
-      buffer->userBuffer = FALSE;
-      buffer->shminfo.shmid = -1;
-      buffer->shminfo.shmaddr = (char *) -1;
-      buffer->shm = TRUE;
-         
-      buffer->data = alloc_shm(buffer, size);
-      if (!buffer->data)
-         goto out;
-
-      return &buffer->base;
-         
-   out:
-      if (buffer)
-         FREE(buffer);
-   }
-#endif
-   
-
-   return winsys->buffer_create(winsys, alignment,
-                                usage,
-                                size);
-}
-
-
-/*
- * Fence functions - basically nothing to do, as we don't create any actual
- * fence objects.
- */
-
-static void
-xm_fence_reference(struct pipe_winsys *sws, struct pipe_fence_handle **ptr,
-                   struct pipe_fence_handle *fence)
-{
-}
-
-
-static int
-xm_fence_signalled(struct pipe_winsys *sws, struct pipe_fence_handle *fence,
-                   unsigned flag)
-{
-   return 0;
-}
-
-
-static int
-xm_fence_finish(struct pipe_winsys *sws, struct pipe_fence_handle *fence,
-                unsigned flag)
-{
-   return 0;
-}
-
-
-
-static struct pipe_winsys *
-xlib_create_softpipe_winsys( void )
-{
-   static struct xmesa_pipe_winsys *ws = NULL;
-
-   if (!ws) {
-      ws = CALLOC_STRUCT(xmesa_pipe_winsys);
-
-      /* Fill in this struct with callbacks that pipe will need to
-       * communicate with the window system, buffer manager, etc. 
-       */
-      ws->base.buffer_create = xm_buffer_create;
-      ws->base.user_buffer_create = xm_user_buffer_create;
-      ws->base.buffer_map = xm_buffer_map;
-      ws->base.buffer_unmap = xm_buffer_unmap;
-      ws->base.buffer_destroy = xm_buffer_destroy;
-
-      ws->base.surface_buffer_create = xm_surface_buffer_create;
-
-      ws->base.fence_reference = xm_fence_reference;
-      ws->base.fence_signalled = xm_fence_signalled;
-      ws->base.fence_finish = xm_fence_finish;
-
-      ws->base.flush_frontbuffer = xm_flush_frontbuffer;
-      ws->base.get_name = xm_get_name;
-   }
-
-   return &ws->base;
-}
-
+#include "softpipe/sp_texture.h"
+#include "softpipe/sp_screen.h"
+#include "state_tracker/sw_winsys.h"
 
 static struct pipe_screen *
 xlib_create_softpipe_screen( void )
 {
-   struct pipe_winsys *winsys;
+   struct sw_winsys *winsys;
    struct pipe_screen *screen;
 
-   winsys = xlib_create_softpipe_winsys();
+   winsys = xlib_create_sw_winsys();
    if (winsys == NULL)
       return NULL;
 
@@ -498,6 +56,18 @@ fail:
 }
 
 
+static void
+xlib_softpipe_display_surface(struct xmesa_buffer *xm_buffer,
+                              struct pipe_surface *surf)
+{
+   struct softpipe_texture *texture = softpipe_texture(surf->texture);
+
+   assert(texture->dt);
+   if (texture->dt)
+      xlib_sw_display(xm_buffer, texture->dt);
+}
+
+
 struct xm_driver xlib_softpipe_driver = 
 {
    .create_pipe_screen = xlib_create_softpipe_screen,
diff --git a/src/gallium/winsys/xlib/xlib_sw_winsys.c b/src/gallium/winsys/xlib/xlib_sw_winsys.c
new file mode 100644
index 00000000000..e4b02ba0935
--- /dev/null
+++ b/src/gallium/winsys/xlib/xlib_sw_winsys.c
@@ -0,0 +1,394 @@
+/**************************************************************************
+ * 
+ * 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 "xm_api.h"
+
+#undef ASSERT
+#undef Elements
+
+#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/sw_winsys.h"
+
+#include "xlib.h"
+
+/**
+ * Subclass of pipe_buffer for Xlib winsys.
+ * Low-level OS/window system memory buffer
+ */
+struct xm_displaytarget
+{
+   enum pipe_format format;
+   unsigned width;
+   unsigned height;
+   unsigned stride;
+
+   void *data;
+   void *mapped;
+
+   XImage *tempImage;
+#ifdef USE_XSHM
+   int shm;
+   XShmSegmentInfo shminfo;
+#endif
+};
+
+
+/**
+ * Subclass of sw_winsys for Xlib winsys
+ */
+struct xmesa_sw_winsys
+{
+   struct sw_winsys base;
+/*   struct xmesa_visual *xm_visual; */
+};
+
+
+
+/** Cast wrapper */
+static INLINE struct xm_displaytarget *
+xm_displaytarget( struct sw_displaytarget *dt )
+{
+   return (struct xm_displaytarget *)dt;
+}
+
+
+/**
+ * X Shared Memory Image extension code
+ */
+
+#ifdef USE_XSHM
+
+static volatile int mesaXErrorFlag = 0;
+
+/**
+ * Catches potential Xlib errors.
+ */
+static int
+mesaHandleXError(Display *dpy, XErrorEvent *event)
+{
+   (void) dpy;
+   (void) event;
+   mesaXErrorFlag = 1;
+   return 0;
+}
+
+
+static char *alloc_shm(struct xm_displaytarget *buf, unsigned size)
+{
+   XShmSegmentInfo *const shminfo = & buf->shminfo;
+
+   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 XMesaBuffer.
+ */
+static void
+alloc_shm_ximage(struct xm_displaytarget *xm_buffer,
+                 struct xmesa_buffer *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 *);
+
+   xm_buffer->tempImage = XShmCreateImage(xmb->xm_visual->display,
+                                  xmb->xm_visual->visinfo->visual,
+                                  xmb->xm_visual->visinfo->depth,
+                                  ZPixmap,
+                                  NULL,
+                                  &xm_buffer->shminfo,
+                                  width, height);
+   if (xm_buffer->tempImage == NULL) {
+      xm_buffer->shm = 0;
+      return;
+   }
+
+
+   mesaXErrorFlag = 0;
+   old_handler = XSetErrorHandler(mesaHandleXError);
+   /* This may trigger the X protocol error we're ready to catch: */
+   XShmAttach(xmb->xm_visual->display, &xm_buffer->shminfo);
+   XSync(xmb->xm_visual->display, False);
+
+   if (mesaXErrorFlag) {
+      /* we are on a remote display, this error is normal, don't print it */
+      XFlush(xmb->xm_visual->display);
+      mesaXErrorFlag = 0;
+      XDestroyImage(xm_buffer->tempImage);
+      xm_buffer->tempImage = NULL;
+      xm_buffer->shm = 0;
+      (void) XSetErrorHandler(old_handler);
+      return;
+   }
+
+   xm_buffer->shm = 1;
+}
+
+#endif /* USE_XSHM */
+
+static boolean
+xm_is_displaytarget_format_supported( struct sw_winsys *ws,
+                                      enum pipe_format format )
+{
+   /* TODO: check visuals or other sensible thing here */
+   return TRUE;
+}
+
+
+static void *
+xm_displaytarget_map(struct sw_winsys *ws,
+                     struct sw_displaytarget *dt,
+                     unsigned flags)
+{
+   struct xm_displaytarget *xm_dt = xm_displaytarget(dt);
+   xm_dt->mapped = xm_dt->data;
+   return xm_dt->mapped;
+}
+
+static void
+xm_displaytarget_unmap(struct sw_winsys *ws,
+                       struct sw_displaytarget *dt)
+{
+   struct xm_displaytarget *xm_dt = xm_displaytarget(dt);
+   xm_dt->mapped = NULL;
+}
+
+static void
+xm_displaytarget_destroy(struct sw_winsys *ws,
+                         struct sw_displaytarget *dt)
+{
+   struct xm_displaytarget *xm_dt = xm_displaytarget(dt);
+
+   if (xm_dt->data) {
+#ifdef USE_XSHM
+      if (xm_dt->shminfo.shmid >= 0) {
+         shmdt(xm_dt->shminfo.shmaddr);
+         shmctl(xm_dt->shminfo.shmid, IPC_RMID, 0);
+         
+         xm_dt->shminfo.shmid = -1;
+         xm_dt->shminfo.shmaddr = (char *) -1;
+      }
+      else
+#endif
+         FREE(xm_dt->data);
+   }
+
+   FREE(xm_dt);
+}
+
+
+/**
+ * Display/copy the image in the surface into the X window specified
+ * by the XMesaBuffer.
+ */
+void
+xlib_sw_display(struct xmesa_buffer *xm_buffer,
+                struct sw_displaytarget *dt)
+{
+   XImage *ximage;
+   struct xm_displaytarget *xm_dt = xm_displaytarget(dt);
+   static boolean no_swap = 0;
+   static boolean firsttime = 1;
+
+   if (firsttime) {
+      no_swap = getenv("SP_NO_RAST") != NULL;
+      firsttime = 0;
+   }
+
+   if (no_swap)
+      return;
+
+#ifdef USE_XSHM
+   if (xm_dt->shm)
+   {
+      if (xm_dt->tempImage == NULL)
+      {
+         assert(util_format_get_blockwidth(xm_dt->format) == 1);
+         assert(util_format_get_blockheight(xm_dt->format) == 1);
+         alloc_shm_ximage(xm_dt, xm_buffer,
+                          xm_dt->stride / util_format_get_blocksize(xm_dt->format),
+                          xm_dt->height);
+      }
+
+      ximage = xm_dt->tempImage;
+      ximage->data = xm_dt->data;
+
+      /* _debug_printf("XSHM\n"); */
+      XShmPutImage(xm_buffer->xm_visual->display, xm_buffer->drawable, xm_buffer->gc,
+                   ximage, 0, 0, 0, 0, xm_dt->width, xm_dt->height, False);
+   }
+   else
+#endif
+   {
+      /* display image in Window */
+      ximage = xm_dt->tempImage;
+      ximage->data = xm_dt->data;
+
+      /* check that the XImage has been previously initialized */
+      assert(ximage->format);
+      assert(ximage->bitmap_unit);
+
+      /* update XImage's fields */
+      ximage->width = xm_dt->width;
+      ximage->height = xm_dt->height;
+      ximage->bytes_per_line = xm_dt->stride;
+
+      /* _debug_printf("XPUT\n"); */
+      XPutImage(xm_buffer->xm_visual->display, xm_buffer->drawable, xm_buffer->gc,
+                ximage, 0, 0, 0, 0, xm_dt->width, xm_dt->height);
+   }
+}
+
+/**
+ * Display/copy the image in the surface into the X window specified
+ * by the XMesaBuffer.
+ */
+static void
+xm_displaytarget_display(struct sw_winsys *ws,
+                         struct sw_displaytarget *dt,
+                         void *context_private)
+{
+   XMesaContext xmctx = (XMesaContext) context_private;
+   struct xmesa_buffer *xm_buffer = xmctx->xm_buffer;
+   xm_sw_display(xm_buffer, dt);
+}
+
+
+static struct sw_displaytarget *
+xm_displaytarget_create(struct sw_winsys *winsys,
+                        enum pipe_format format,
+                        unsigned width, unsigned height,
+                        unsigned alignment,
+                        unsigned *stride)
+{
+   struct xm_displaytarget *xm_dt = CALLOC_STRUCT(xm_displaytarget);
+   unsigned nblocksy, size;
+
+   xm_dt = CALLOC_STRUCT(xm_displaytarget);
+   if(!xm_dt)
+      goto no_xm_dt;
+
+   xm_dt->format = format;
+   xm_dt->width = width;
+   xm_dt->height = height;
+
+   nblocksy = util_format_get_nblocksy(format, height);
+   xm_dt->stride = align(util_format_get_stride(format, width), alignment);
+   size = xm_dt->stride * nblocksy;
+
+#ifdef USE_XSHM
+   if (!debug_get_bool_option("XLIB_NO_SHM", FALSE))
+   {
+      xm_dt->shminfo.shmid = -1;
+      xm_dt->shminfo.shmaddr = (char *) -1;
+      xm_dt->shm = TRUE;
+         
+      xm_dt->data = alloc_shm(xm_dt, size);
+      if(!xm_dt->data)
+         goto no_data;
+   }
+#endif
+
+   if(!xm_dt->data) {
+      xm_dt->data = align_malloc(size, alignment);
+      if(!xm_dt->data)
+         goto no_data;
+   }
+
+   *stride = xm_dt->stride;
+   return (struct sw_displaytarget *)xm_dt;
+
+no_data:
+   FREE(xm_dt);
+no_xm_dt:
+   return NULL;
+}
+
+
+static void
+xm_destroy( struct sw_winsys *ws )
+{
+   FREE(ws);
+}
+
+
+struct sw_winsys *
+xlib_create_sw_winsys( void )
+{
+   struct xmesa_sw_winsys *ws;
+
+   ws = CALLOC_STRUCT(xmesa_sw_winsys);
+   if (!ws)
+      return NULL;
+
+   ws->base.destroy = xm_destroy;
+
+   ws->base.is_displaytarget_format_supported = xm_is_displaytarget_format_supported;
+
+   ws->base.displaytarget_create = xm_displaytarget_create;
+   ws->base.displaytarget_map = xm_displaytarget_map;
+   ws->base.displaytarget_unmap = xm_displaytarget_unmap;
+   ws->base.displaytarget_destroy = xm_displaytarget_destroy;
+
+   ws->base.displaytarget_display = xm_displaytarget_display;
+
+   return &ws->base;
+}
+