Retire miniglx and move the actual glx code up to src/glx

1 files changed, 3173 insertions, 0 deletions

diff --git a/src/glx/glxcmds.c b/src/glx/glxcmds.c
new file mode 100644
index 0000000..c3be974
--- /dev/null
+++ b/src/glx/glxcmds.c
@@ -0,0 +1,3173 @@
+/*
+ * SGI FREE SOFTWARE LICENSE B (Version 2.0, Sept. 18, 2008)
+ * Copyright (C) 1991-2000 Silicon Graphics, Inc. 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, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice including the dates of first publication and
+ * either this permission notice or a reference to
+ * http://oss.sgi.com/projects/FreeB/
+ * 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
+ * SILICON GRAPHICS, INC. 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 Silicon Graphics, Inc.
+ * shall not be used in advertising or otherwise to promote the sale, use or
+ * other dealings in this Software without prior written authorization from
+ * Silicon Graphics, Inc.
+ */
+
+/**
+ * \file glxcmds.c
+ * Client-side GLX interface.
+ */
+
+#include "glxclient.h"
+#include "glapi.h"
+#include "glxextensions.h"
+#include "glcontextmodes.h"
+
+#ifdef GLX_DIRECT_RENDERING
+#include <sys/time.h>
+#include <X11/extensions/xf86vmode.h>
+#include "xf86dri.h"
+#endif
+
+#if defined(USE_XCB)
+#include <X11/Xlib-xcb.h>
+#include <xcb/xcb.h>
+#include <xcb/glx.h>
+#endif
+
+static const char __glXGLXClientVendorName[] = "Mesa Project and SGI";
+static const char __glXGLXClientVersion[] = "1.4";
+
+
+/****************************************************************************/
+
+#ifdef GLX_DIRECT_RENDERING
+
+static Bool windowExistsFlag;
+static int
+windowExistsErrorHandler(Display * dpy, XErrorEvent * xerr)
+{
+   if (xerr->error_code == BadWindow) {
+      windowExistsFlag = GL_FALSE;
+   }
+   return 0;
+}
+
+/**
+ * Find drawables in the local hash that have been destroyed on the
+ * server.
+ *
+ * \param dpy    Display to destroy drawables for
+ * \param screen Screen number to destroy drawables for
+ */
+static void
+GarbageCollectDRIDrawables(Display * dpy, __GLXscreenConfigs * sc)
+{
+   XID draw;
+   __GLXDRIdrawable *pdraw;
+   XWindowAttributes xwa;
+   int (*oldXErrorHandler) (Display *, XErrorEvent *);
+
+   /* Set no-op error handler so Xlib doesn't bail out if the windows
+    * has alreay been destroyed on the server. */
+   XSync(dpy, GL_FALSE);
+   oldXErrorHandler = XSetErrorHandler(windowExistsErrorHandler);
+
+   if (__glxHashFirst(sc->drawHash, &draw, (void *) &pdraw) == 1) {
+      do {
+         windowExistsFlag = GL_TRUE;
+         XGetWindowAttributes(dpy, draw, &xwa); /* dummy request */
+         if (!windowExistsFlag) {
+            /* Destroy the local drawable data, if the drawable no
+               longer exists in the Xserver */
+            (*pdraw->destroyDrawable) (pdraw);
+            __glxHashDelete(sc->drawHash, draw);
+         }
+      } while (__glxHashNext(sc->drawHash, &draw, (void *) &pdraw) == 1);
+   }
+
+   XSync(dpy, GL_FALSE);
+   XSetErrorHandler(oldXErrorHandler);
+}
+
+extern __GLXDRIdrawable *GetGLXDRIDrawable(Display * dpy,
+                                           GLXDrawable drawable,
+                                           int *const scrn_num);
+
+/**
+ * Get the __DRIdrawable for the drawable associated with a GLXContext
+ *
+ * \param dpy       The display associated with \c drawable.
+ * \param drawable  GLXDrawable whose __DRIdrawable part is to be retrieved.
+ * \param scrn_num  If non-NULL, the drawables screen is stored there
+ * \returns  A pointer to the context's __DRIdrawable on success, or NULL if
+ *           the drawable is not associated with a direct-rendering context.
+ */
+_X_HIDDEN __GLXDRIdrawable *
+GetGLXDRIDrawable(Display * dpy, GLXDrawable drawable, int *const scrn_num)
+{
+   __GLXdisplayPrivate *priv = __glXInitialize(dpy);
+   __GLXDRIdrawable *pdraw;
+   const unsigned screen_count = ScreenCount(dpy);
+   unsigned i;
+   __GLXscreenConfigs *psc;
+
+   if (priv == NULL)
+      return NULL;
+
+   for (i = 0; i < screen_count; i++) {
+      psc = &priv->screenConfigs[i];
+      if (psc->drawHash == NULL)
+         continue;
+
+      if (__glxHashLookup(psc->drawHash, drawable, (void *) &pdraw) == 0) {
+         if (scrn_num != NULL)
+            *scrn_num = i;
+         return pdraw;
+      }
+   }
+
+   return NULL;
+}
+
+#endif
+
+
+/**
+ * Get the GLX per-screen data structure associated with a GLX context.
+ *
+ * \param dpy   Display for which the GLX per-screen information is to be
+ *              retrieved.
+ * \param scrn  Screen on \c dpy for which the GLX per-screen information is
+ *              to be retrieved.
+ * \returns A pointer to the GLX per-screen data if \c dpy and \c scrn
+ *          specify a valid GLX screen, or NULL otherwise.
+ *
+ * \todo Should this function validate that \c scrn is within the screen
+ *       number range for \c dpy?
+ */
+
+static __GLXscreenConfigs *
+GetGLXScreenConfigs(Display * dpy, int scrn)
+{
+   __GLXdisplayPrivate *const priv = __glXInitialize(dpy);
+
+   return (priv
+           && priv->screenConfigs !=
+           NULL) ? &priv->screenConfigs[scrn] : NULL;
+}
+
+
+static int
+GetGLXPrivScreenConfig(Display * dpy, int scrn, __GLXdisplayPrivate ** ppriv,
+                       __GLXscreenConfigs ** ppsc)
+{
+   /* Initialize the extension, if needed .  This has the added value
+    * of initializing/allocating the display private
+    */
+
+   if (dpy == NULL) {
+      return GLX_NO_EXTENSION;
+   }
+
+   *ppriv = __glXInitialize(dpy);
+   if (*ppriv == NULL) {
+      return GLX_NO_EXTENSION;
+   }
+
+   /* Check screen number to see if its valid */
+   if ((scrn < 0) || (scrn >= ScreenCount(dpy))) {
+      return GLX_BAD_SCREEN;
+   }
+
+   /* Check to see if the GL is supported on this screen */
+   *ppsc = &((*ppriv)->screenConfigs[scrn]);
+   if ((*ppsc)->configs == NULL) {
+      /* No support for GL on this screen regardless of visual */
+      return GLX_BAD_VISUAL;
+   }
+
+   return Success;
+}
+
+
+/**
+ * Determine if a \c GLXFBConfig supplied by the application is valid.
+ *
+ * \param dpy     Application supplied \c Display pointer.
+ * \param config  Application supplied \c GLXFBConfig.
+ *
+ * \returns If the \c GLXFBConfig is valid, the a pointer to the matching
+ *          \c __GLcontextModes structure is returned.  Otherwise, \c NULL
+ *          is returned.
+ */
+static __GLcontextModes *
+ValidateGLXFBConfig(Display * dpy, GLXFBConfig config)
+{
+   __GLXdisplayPrivate *const priv = __glXInitialize(dpy);
+   const unsigned num_screens = ScreenCount(dpy);
+   unsigned i;
+   const __GLcontextModes *modes;
+
+
+   if (priv != NULL) {
+      for (i = 0; i < num_screens; i++) {
+         for (modes = priv->screenConfigs[i].configs; modes != NULL;
+              modes = modes->next) {
+            if (modes == (__GLcontextModes *) config) {
+               return (__GLcontextModes *) config;
+            }
+         }
+      }
+   }
+
+   return NULL;
+}
+
+
+/**
+ * \todo It should be possible to move the allocate of \c client_state_private
+ * later in the function for direct-rendering contexts.  Direct-rendering
+ * contexts don't need to track client state, so they don't need that memory
+ * at all.
+ *
+ * \todo Eliminate \c __glXInitVertexArrayState.  Replace it with a new
+ * function called \c __glXAllocateClientState that allocates the memory and
+ * does all the initialization (including the pixel pack / unpack).
+ */
+static GLXContext
+AllocateGLXContext(Display * dpy)
+{
+   GLXContext gc;
+   int bufSize;
+   CARD8 opcode;
+   __GLXattribute *state;
+
+   if (!dpy)
+      return NULL;
+
+   opcode = __glXSetupForCommand(dpy);
+   if (!opcode) {
+      return NULL;
+   }
+
+   /* Allocate our context record */
+   gc = (GLXContext) Xmalloc(sizeof(struct __GLXcontextRec));
+   if (!gc) {
+      /* Out of memory */
+      return NULL;
+   }
+   memset(gc, 0, sizeof(struct __GLXcontextRec));
+
+   state = Xmalloc(sizeof(struct __GLXattributeRec));
+   if (state == NULL) {
+      /* Out of memory */
+      Xfree(gc);
+      return NULL;
+   }
+   gc->client_state_private = state;
+   memset(gc->client_state_private, 0, sizeof(struct __GLXattributeRec));
+   state->NoDrawArraysProtocol = (getenv("LIBGL_NO_DRAWARRAYS") != NULL);
+
+   /*
+    ** Create a temporary buffer to hold GLX rendering commands.  The size
+    ** of the buffer is selected so that the maximum number of GLX rendering
+    ** commands can fit in a single X packet and still have room in the X
+    ** packet for the GLXRenderReq header.
+    */
+
+   bufSize = (XMaxRequestSize(dpy) * 4) - sz_xGLXRenderReq;
+   gc->buf = (GLubyte *) Xmalloc(bufSize);
+   if (!gc->buf) {
+      Xfree(gc->client_state_private);
+      Xfree(gc);
+      return NULL;
+   }
+   gc->bufSize = bufSize;
+
+   /* Fill in the new context */
+   gc->renderMode = GL_RENDER;
+
+   state->storePack.alignment = 4;
+   state->storeUnpack.alignment = 4;
+
+   gc->attributes.stackPointer = &gc->attributes.stack[0];
+
+   /*
+    ** PERFORMANCE NOTE: A mode dependent fill image can speed things up.
+    ** Other code uses the fastImageUnpack bit, but it is never set
+    ** to GL_TRUE.
+    */
+   gc->fastImageUnpack = GL_FALSE;
+   gc->fillImage = __glFillImage;
+   gc->pc = gc->buf;
+   gc->bufEnd = gc->buf + bufSize;
+   gc->isDirect = GL_FALSE;
+   if (__glXDebug) {
+      /*
+       ** Set limit register so that there will be one command per packet
+       */
+      gc->limit = gc->buf;
+   }
+   else {
+      gc->limit = gc->buf + bufSize - __GLX_BUFFER_LIMIT_SIZE;
+   }
+   gc->createDpy = dpy;
+   gc->majorOpcode = opcode;
+
+   /*
+    ** Constrain the maximum drawing command size allowed to be
+    ** transfered using the X_GLXRender protocol request.  First
+    ** constrain by a software limit, then constrain by the protocl
+    ** limit.
+    */
+   if (bufSize > __GLX_RENDER_CMD_SIZE_LIMIT) {
+      bufSize = __GLX_RENDER_CMD_SIZE_LIMIT;
+   }
+   if (bufSize > __GLX_MAX_RENDER_CMD_SIZE) {
+      bufSize = __GLX_MAX_RENDER_CMD_SIZE;
+   }
+   gc->maxSmallRenderCommandSize = bufSize;
+   return gc;
+}
+
+
+/**
+ * Create a new context.  Exactly one of \c vis and \c fbconfig should be
+ * non-NULL.
+ *
+ * \param use_glx_1_3  For FBConfigs, should GLX 1.3 protocol or
+ *                     SGIX_fbconfig protocol be used?
+ * \param renderType   For FBConfigs, what is the rendering type?
+ */
+
+static GLXContext
+CreateContext(Display * dpy, XVisualInfo * vis,
+              const __GLcontextModes * const fbconfig,
+              GLXContext shareList,
+              Bool allowDirect, GLXContextID contextID,
+              Bool use_glx_1_3, int renderType)
+{
+   GLXContext gc;
+#ifdef GLX_DIRECT_RENDERING
+   int screen = (fbconfig == NULL) ? vis->screen : fbconfig->screen;
+   __GLXscreenConfigs *const psc = GetGLXScreenConfigs(dpy, screen);
+#endif
+
+   if (dpy == NULL)
+      return NULL;
+
+   gc = AllocateGLXContext(dpy);
+   if (!gc)
+      return NULL;
+
+   if (None == contextID) {
+      if ((vis == NULL) && (fbconfig == NULL))
+         return NULL;
+
+#ifdef GLX_DIRECT_RENDERING
+      if (allowDirect && psc->driScreen) {
+         const __GLcontextModes *mode;
+
+         if (fbconfig == NULL) {
+            mode = _gl_context_modes_find_visual(psc->visuals, vis->visualid);
+            if (mode == NULL) {
+               xError error;
+
+               error.errorCode = BadValue;
+               error.resourceID = vis->visualid;
+               error.sequenceNumber = dpy->request;
+               error.type = X_Error;
+               error.majorCode = gc->majorOpcode;
+               error.minorCode = X_GLXCreateContext;
+               _XError(dpy, &error);
+               return None;
+            }
+            if (renderType == 0) {
+               /* Initialize renderType now */
+               renderType = mode->rgbMode ? GLX_RGBA_TYPE : GLX_COLOR_INDEX_TYPE;
+            }
+         }
+         else {
+            mode = fbconfig;
+         }
+
+         gc->driContext = psc->driScreen->createContext(psc, mode, gc,
+                                                        shareList,
+                                                        renderType);
+         if (gc->driContext != NULL) {
+            gc->screen = mode->screen;
+            gc->psc = psc;
+            gc->mode = mode;
+            gc->isDirect = GL_TRUE;
+         }
+      }
+#endif
+
+      LockDisplay(dpy);
+      if (fbconfig == NULL) {
+         xGLXCreateContextReq *req;
+
+         /* Send the glXCreateContext request */
+         GetReq(GLXCreateContext, req);
+         req->reqType = gc->majorOpcode;
+         req->glxCode = X_GLXCreateContext;
+         req->context = gc->xid = XAllocID(dpy);
+         req->visual = vis->visualid;
+         req->screen = vis->screen;
+         req->shareList = shareList ? shareList->xid : None;
+#ifdef GLX_DIRECT_RENDERING
+         req->isDirect = gc->driContext != NULL;
+#else
+         req->isDirect = 0;
+#endif
+      }
+      else if (use_glx_1_3) {
+         xGLXCreateNewContextReq *req;
+
+         /* Send the glXCreateNewContext request */
+         GetReq(GLXCreateNewContext, req);
+         req->reqType = gc->majorOpcode;
+         req->glxCode = X_GLXCreateNewContext;
+         req->context = gc->xid = XAllocID(dpy);
+         req->fbconfig = fbconfig->fbconfigID;
+         req->screen = fbconfig->screen;
+         req->renderType = renderType;
+         req->shareList = shareList ? shareList->xid : None;
+#ifdef GLX_DIRECT_RENDERING
+         req->isDirect = gc->driContext != NULL;
+#else
+         req->isDirect = 0;
+#endif
+      }
+      else {
+         xGLXVendorPrivateWithReplyReq *vpreq;
+         xGLXCreateContextWithConfigSGIXReq *req;
+
+         /* Send the glXCreateNewContext request */
+         GetReqExtra(GLXVendorPrivateWithReply,
+                     sz_xGLXCreateContextWithConfigSGIXReq -
+                     sz_xGLXVendorPrivateWithReplyReq, vpreq);
+         req = (xGLXCreateContextWithConfigSGIXReq *) vpreq;
+         req->reqType = gc->majorOpcode;
+         req->glxCode = X_GLXVendorPrivateWithReply;
+         req->vendorCode = X_GLXvop_CreateContextWithConfigSGIX;
+         req->context = gc->xid = XAllocID(dpy);
+         req->fbconfig = fbconfig->fbconfigID;
+         req->screen = fbconfig->screen;
+         req->renderType = renderType;
+         req->shareList = shareList ? shareList->xid : None;
+#ifdef GLX_DIRECT_RENDERING
+         req->isDirect = gc->driContext != NULL;
+#else
+         req->isDirect = 0;
+#endif
+      }
+
+      UnlockDisplay(dpy);
+      SyncHandle();
+      gc->imported = GL_FALSE;
+   }
+   else {
+      gc->xid = contextID;
+      gc->imported = GL_TRUE;
+   }
+
+   gc->renderType = renderType;
+
+   return gc;
+}
+
+PUBLIC GLXContext
+glXCreateContext(Display * dpy, XVisualInfo * vis,
+                 GLXContext shareList, Bool allowDirect)
+{
+   return CreateContext(dpy, vis, NULL, shareList, allowDirect, None,
+                        False, 0);
+}
+
+_X_HIDDEN void
+__glXFreeContext(__GLXcontext * gc)
+{
+   if (gc->vendor)
+      XFree((char *) gc->vendor);
+   if (gc->renderer)
+      XFree((char *) gc->renderer);
+   if (gc->version)
+      XFree((char *) gc->version);
+   if (gc->extensions)
+      XFree((char *) gc->extensions);
+   __glFreeAttributeState(gc);
+   XFree((char *) gc->buf);
+   Xfree((char *) gc->client_state_private);
+   XFree((char *) gc);
+
+}
+
+/*
+** Destroy the named context
+*/
+static void
+DestroyContext(Display * dpy, GLXContext gc)
+{
+   xGLXDestroyContextReq *req;
+   GLXContextID xid;
+   CARD8 opcode;
+   GLboolean imported;
+
+   opcode = __glXSetupForCommand(dpy);
+   if (!opcode || !gc) {
+      return;
+   }
+
+   __glXLock();
+   xid = gc->xid;
+   imported = gc->imported;
+   gc->xid = None;
+
+   if (gc->currentDpy) {
+      /* This context is bound to some thread.  According to the man page,
+       * we should not actually delete the context until it's unbound.
+       * Note that we set gc->xid = None above.  In MakeContextCurrent()
+       * we check for that and delete the context there.
+       */
+      __glXUnlock();
+      return;
+   }
+
+#ifdef GLX_DIRECT_RENDERING
+   /* Destroy the direct rendering context */
+   if (gc->driContext) {
+      (*gc->driContext->destroyContext) (gc->driContext, gc->psc, dpy);
+      gc->driContext = NULL;
+      GarbageCollectDRIDrawables(dpy, gc->psc);
+   }
+#endif
+
+   __glXFreeVertexArrayState(gc);
+
+   if (gc->currentDpy) {
+      /* Have to free later cuz it's in use now */
+      __glXUnlock();
+   }
+   else {
+      /* Destroy the handle if not current to anybody */
+      __glXUnlock();
+      __glXFreeContext(gc);
+   }
+
+   if (!imported) {
+      /*
+       ** This dpy also created the server side part of the context.
+       ** Send the glXDestroyContext request.
+       */
+      LockDisplay(dpy);
+      GetReq(GLXDestroyContext, req);
+      req->reqType = opcode;
+      req->glxCode = X_GLXDestroyContext;
+      req->context = xid;
+      UnlockDisplay(dpy);
+      SyncHandle();
+   }
+}
+
+PUBLIC void
+glXDestroyContext(Display * dpy, GLXContext gc)
+{
+   DestroyContext(dpy, gc);
+}
+
+/*
+** Return the major and minor version #s for the GLX extension
+*/
+PUBLIC Bool
+glXQueryVersion(Display * dpy, int *major, int *minor)
+{
+   __GLXdisplayPrivate *priv;
+
+   /* Init the extension.  This fetches the major and minor version. */
+   priv = __glXInitialize(dpy);
+   if (!priv)
+      return GL_FALSE;
+
+   if (major)
+      *major = priv->majorVersion;
+   if (minor)
+      *minor = priv->minorVersion;
+   return GL_TRUE;
+}
+
+/*
+** Query the existance of the GLX extension
+*/
+PUBLIC Bool
+glXQueryExtension(Display * dpy, int *errorBase, int *eventBase)
+{
+   int major_op, erb, evb;
+   Bool rv;
+
+   rv = XQueryExtension(dpy, GLX_EXTENSION_NAME, &major_op, &evb, &erb);
+   if (rv) {
+      if (errorBase)
+         *errorBase = erb;
+      if (eventBase)
+         *eventBase = evb;
+   }
+   return rv;
+}
+
+/*
+** Put a barrier in the token stream that forces the GL to finish its
+** work before X can proceed.
+*/
+PUBLIC void
+glXWaitGL(void)
+{
+   xGLXWaitGLReq *req;
+   GLXContext gc = __glXGetCurrentContext();
+   Display *dpy = gc->currentDpy;
+
+   if (!dpy)
+      return;
+
+   /* Flush any pending commands out */
+   __glXFlushRenderBuffer(gc, gc->pc);
+
+#ifdef GLX_DIRECT_RENDERING
+   if (gc->driContext) {
+      int screen;
+      __GLXDRIdrawable *pdraw =
+         GetGLXDRIDrawable(dpy, gc->currentDrawable, &screen);
+
+      if (pdraw != NULL) {
+         __GLXscreenConfigs *const psc = GetGLXScreenConfigs(dpy, screen);
+         glFlush();
+         if (psc->driScreen->waitGL != NULL)
+            (*psc->driScreen->waitGL) (pdraw);
+      }
+      return;
+   }
+#endif
+
+   /* Send the glXWaitGL request */
+   LockDisplay(dpy);
+   GetReq(GLXWaitGL, req);
+   req->reqType = gc->majorOpcode;
+   req->glxCode = X_GLXWaitGL;
+   req->contextTag = gc->currentContextTag;
+   UnlockDisplay(dpy);
+   SyncHandle();
+}
+
+/*
+** Put a barrier in the token stream that forces X to finish its
+** work before GL can proceed.
+*/
+PUBLIC void
+glXWaitX(void)
+{
+   xGLXWaitXReq *req;
+   GLXContext gc = __glXGetCurrentContext();
+   Display *dpy = gc->currentDpy;
+
+   if (!dpy)
+      return;
+
+   /* Flush any pending commands out */
+   __glXFlushRenderBuffer(gc, gc->pc);
+
+#ifdef GLX_DIRECT_RENDERING
+   if (gc->driContext) {
+      int screen;
+      __GLXDRIdrawable *pdraw =
+         GetGLXDRIDrawable(dpy, gc->currentDrawable, &screen);
+
+      if (pdraw != NULL) {
+         __GLXscreenConfigs *const psc = GetGLXScreenConfigs(dpy, screen);
+         if (psc->driScreen->waitX != NULL)
+            (*psc->driScreen->waitX) (pdraw);
+      }
+      else
+         XSync(dpy, False);
+      return;
+   }
+#endif
+
+   /*
+    ** Send the glXWaitX request.
+    */
+   LockDisplay(dpy);
+   GetReq(GLXWaitX, req);
+   req->reqType = gc->majorOpcode;
+   req->glxCode = X_GLXWaitX;
+   req->contextTag = gc->currentContextTag;
+   UnlockDisplay(dpy);
+   SyncHandle();
+}
+
+PUBLIC void
+glXUseXFont(Font font, int first, int count, int listBase)
+{
+   xGLXUseXFontReq *req;
+   GLXContext gc = __glXGetCurrentContext();
+   Display *dpy = gc->currentDpy;
+
+   if (!dpy)
+      return;
+
+   /* Flush any pending commands out */
+   (void) __glXFlushRenderBuffer(gc, gc->pc);
+
+#ifdef GLX_DIRECT_RENDERING
+   if (gc->driContext) {
+      DRI_glXUseXFont(font, first, count, listBase);
+      return;
+   }
+#endif
+
+   /* Send the glXUseFont request */
+   LockDisplay(dpy);
+   GetReq(GLXUseXFont, req);
+   req->reqType = gc->majorOpcode;
+   req->glxCode = X_GLXUseXFont;
+   req->contextTag = gc->currentContextTag;
+   req->font = font;
+   req->first = first;
+   req->count = count;
+   req->listBase = listBase;
+   UnlockDisplay(dpy);
+   SyncHandle();
+}
+
+/************************************************************************/
+
+/*
+** Copy the source context to the destination context using the
+** attribute "mask".
+*/
+PUBLIC void
+glXCopyContext(Display * dpy, GLXContext source,
+               GLXContext dest, unsigned long mask)
+{
+   xGLXCopyContextReq *req;
+   GLXContext gc = __glXGetCurrentContext();
+   GLXContextTag tag;
+   CARD8 opcode;
+
+   opcode = __glXSetupForCommand(dpy);
+   if (!opcode) {
+      return;
+   }
+
+#ifdef GLX_DIRECT_RENDERING
+   if (gc->driContext) {
+      /* NOT_DONE: This does not work yet */
+   }
+#endif
+
+   /*
+    ** If the source is the current context, send its tag so that the context
+    ** can be flushed before the copy.
+    */
+   if (source == gc && dpy == gc->currentDpy) {
+      tag = gc->currentContextTag;
+   }
+   else {
+      tag = 0;
+   }
+
+   /* Send the glXCopyContext request */
+   LockDisplay(dpy);
+   GetReq(GLXCopyContext, req);
+   req->reqType = opcode;
+   req->glxCode = X_GLXCopyContext;
+   req->source = source ? source->xid : None;
+   req->dest = dest ? dest->xid : None;
+   req->mask = mask;
+   req->contextTag = tag;
+   UnlockDisplay(dpy);
+   SyncHandle();
+}
+
+
+/**
+ * Determine if a context uses direct rendering.
+ *
+ * \param dpy        Display where the context was created.
+ * \param contextID  ID of the context to be tested.
+ *
+ * \returns \c GL_TRUE if the context is direct rendering or not.
+ */
+static Bool
+__glXIsDirect(Display * dpy, GLXContextID contextID)
+{
+#if !defined(USE_XCB)
+   xGLXIsDirectReq *req;
+   xGLXIsDirectReply reply;
+#endif
+   CARD8 opcode;
+
+   opcode = __glXSetupForCommand(dpy);
+   if (!opcode) {
+      return GL_FALSE;
+   }
+
+#ifdef USE_XCB
+   xcb_connection_t *c = XGetXCBConnection(dpy);
+   xcb_glx_is_direct_reply_t *reply = xcb_glx_is_direct_reply(c,
+                                                              xcb_glx_is_direct
+                                                              (c, contextID),
+                                                              NULL);
+
+   const Bool is_direct = reply->is_direct ? True : False;
+   free(reply);
+
+   return is_direct;
+#else
+   /* Send the glXIsDirect request */
+   LockDisplay(dpy);
+   GetReq(GLXIsDirect, req);
+   req->reqType = opcode;
+   req->glxCode = X_GLXIsDirect;
+   req->context = contextID;
+   _XReply(dpy, (xReply *) & reply, 0, False);
+   UnlockDisplay(dpy);
+   SyncHandle();
+
+   return reply.isDirect;
+#endif /* USE_XCB */
+}
+
+/**
+ * \todo
+ * Shouldn't this function \b always return \c GL_FALSE when
+ * \c GLX_DIRECT_RENDERING is not defined?  Do we really need to bother with
+ * the GLX protocol here at all?
+ */
+PUBLIC Bool
+glXIsDirect(Display * dpy, GLXContext gc)
+{
+   if (!gc) {
+      return GL_FALSE;
+#ifdef GLX_DIRECT_RENDERING
+   }
+   else if (gc->driContext) {
+      return GL_TRUE;
+#endif
+   }
+   return __glXIsDirect(dpy, gc->xid);
+}
+
+PUBLIC GLXPixmap
+glXCreateGLXPixmap(Display * dpy, XVisualInfo * vis, Pixmap pixmap)
+{
+   xGLXCreateGLXPixmapReq *req;
+   GLXPixmap xid;
+   CARD8 opcode;
+
+   opcode = __glXSetupForCommand(dpy);
+   if (!opcode) {
+      return None;
+   }
+
+   /* Send the glXCreateGLXPixmap request */
+   LockDisplay(dpy);
+   GetReq(GLXCreateGLXPixmap, req);
+   req->reqType = opcode;
+   req->glxCode = X_GLXCreateGLXPixmap;
+   req->screen = vis->screen;
+   req->visual = vis->visualid;
+   req->pixmap = pixmap;
+   req->glxpixmap = xid = XAllocID(dpy);
+   UnlockDisplay(dpy);
+   SyncHandle();
+
+#ifdef GLX_DIRECT_RENDERING
+   do {
+      /* FIXME: Maybe delay __DRIdrawable creation until the drawable
+       * is actually bound to a context... */
+
+      __GLXdisplayPrivate *const priv = __glXInitialize(dpy);
+      __GLXDRIdrawable *pdraw;
+      __GLXscreenConfigs *psc;
+      __GLcontextModes *modes;
+
+      psc = &priv->screenConfigs[vis->screen];
+      if (psc->driScreen == NULL)
+         break;
+      modes = _gl_context_modes_find_visual(psc->visuals, vis->visualid);
+      pdraw = psc->driScreen->createDrawable(psc, pixmap, req->glxpixmap, modes);
+      if (pdraw == NULL) {
+         fprintf(stderr, "failed to create pixmap\n");
+         break;
+      }
+
+      if (__glxHashInsert(psc->drawHash, req->glxpixmap, pdraw)) {
+         (*pdraw->destroyDrawable) (pdraw);
+         return None;           /* FIXME: Check what we're supposed to do here... */
+      }
+   } while (0);
+#endif
+
+   return xid;
+}
+
+/*
+** Destroy the named pixmap
+*/
+PUBLIC void
+glXDestroyGLXPixmap(Display * dpy, GLXPixmap glxpixmap)
+{
+   xGLXDestroyGLXPixmapReq *req;
+   CARD8 opcode;
+
+   opcode = __glXSetupForCommand(dpy);
+   if (!opcode) {
+      return;
+   }
+
+   /* Send the glXDestroyGLXPixmap request */
+   LockDisplay(dpy);
+   GetReq(GLXDestroyGLXPixmap, req);
+   req->reqType = opcode;
+   req->glxCode = X_GLXDestroyGLXPixmap;
+   req->glxpixmap = glxpixmap;
+   UnlockDisplay(dpy);
+   SyncHandle();
+
+#ifdef GLX_DIRECT_RENDERING
+   {
+      int screen;
+      __GLXdisplayPrivate *const priv = __glXInitialize(dpy);
+      __GLXDRIdrawable *pdraw = GetGLXDRIDrawable(dpy, glxpixmap, &screen);
+      __GLXscreenConfigs *psc = &priv->screenConfigs[screen];
+
+      if (pdraw != NULL) {
+         (*pdraw->destroyDrawable) (pdraw);
+         __glxHashDelete(psc->drawHash, glxpixmap);
+      }
+   }
+#endif
+}
+
+PUBLIC void
+glXSwapBuffers(Display * dpy, GLXDrawable drawable)
+{
+   GLXContext gc;
+   GLXContextTag tag;
+   CARD8 opcode;
+#ifdef USE_XCB
+   xcb_connection_t *c;
+#else
+   xGLXSwapBuffersReq *req;
+#endif
+
+#ifdef GLX_DIRECT_RENDERING
+   __GLXDRIdrawable *pdraw = GetGLXDRIDrawable(dpy, drawable, NULL);
+
+   if (pdraw != NULL) {
+      glFlush();
+      (*pdraw->psc->driScreen->swapBuffers)(pdraw, 0, 0, 0);
+      return;
+   }
+#endif
+
+   opcode = __glXSetupForCommand(dpy);
+   if (!opcode) {
+      return;
+   }
+
+   /*
+    ** The calling thread may or may not have a current context.  If it
+    ** does, send the context tag so the server can do a flush.
+    */
+   gc = __glXGetCurrentContext();
+   if ((gc != NULL) && (dpy == gc->currentDpy) &&
+       ((drawable == gc->currentDrawable)
+        || (drawable == gc->currentReadable))) {
+      tag = gc->currentContextTag;
+   }
+   else {
+      tag = 0;
+   }
+
+#ifdef USE_XCB
+   c = XGetXCBConnection(dpy);
+   xcb_glx_swap_buffers(c, tag, drawable);
+   xcb_flush(c);
+#else
+   /* Send the glXSwapBuffers request */
+   LockDisplay(dpy);
+   GetReq(GLXSwapBuffers, req);
+   req->reqType = opcode;
+   req->glxCode = X_GLXSwapBuffers;
+   req->drawable = drawable;
+   req->contextTag = tag;
+   UnlockDisplay(dpy);
+   SyncHandle();
+   XFlush(dpy);
+#endif /* USE_XCB */
+}
+
+
+/*
+** Return configuration information for the given display, screen and
+** visual combination.
+*/
+PUBLIC int
+glXGetConfig(Display * dpy, XVisualInfo * vis, int attribute,
+             int *value_return)
+{
+   __GLXdisplayPrivate *priv;
+   __GLXscreenConfigs *psc;
+   __GLcontextModes *modes;
+   int status;
+
+   status = GetGLXPrivScreenConfig(dpy, vis->screen, &priv, &psc);
+   if (status == Success) {
+      modes = _gl_context_modes_find_visual(psc->visuals, vis->visualid);
+
+      /* Lookup attribute after first finding a match on the visual */
+      if (modes != NULL) {
+         return _gl_get_context_mode_data(modes, attribute, value_return);
+      }
+
+      status = GLX_BAD_VISUAL;
+   }
+
+   /*
+    ** If we can't find the config for this visual, this visual is not
+    ** supported by the OpenGL implementation on the server.
+    */
+   if ((status == GLX_BAD_VISUAL) && (attribute == GLX_USE_GL)) {
+      *value_return = GL_FALSE;
+      status = Success;
+   }
+
+   return status;
+}
+
+/************************************************************************/
+
+static void
+init_fbconfig_for_chooser(__GLcontextModes * config,
+                          GLboolean fbconfig_style_tags)
+{
+   memset(config, 0, sizeof(__GLcontextModes));
+   config->visualID = (XID) GLX_DONT_CARE;
+   config->visualType = GLX_DONT_CARE;
+
+   /* glXChooseFBConfig specifies different defaults for these two than
+    * glXChooseVisual.
+    */
+   if (fbconfig_style_tags) {
+      config->rgbMode = GL_TRUE;
+      config->doubleBufferMode = GLX_DONT_CARE;
+   }
+
+   config->visualRating = GLX_DONT_CARE;
+   config->transparentPixel = GLX_NONE;
+   config->transparentRed = GLX_DONT_CARE;
+   config->transparentGreen = GLX_DONT_CARE;
+   config->transparentBlue = GLX_DONT_CARE;
+   config->transparentAlpha = GLX_DONT_CARE;
+   config->transparentIndex = GLX_DONT_CARE;
+
+   config->drawableType = GLX_WINDOW_BIT;
+   config->renderType =
+      (config->rgbMode) ? GLX_RGBA_BIT : GLX_COLOR_INDEX_BIT;
+   config->xRenderable = GLX_DONT_CARE;
+   config->fbconfigID = (GLXFBConfigID) (GLX_DONT_CARE);
+
+   config->swapMethod = GLX_DONT_CARE;
+}
+
+#define MATCH_DONT_CARE( param )        \
+  do {                                  \
+    if ( (a-> param != GLX_DONT_CARE)   \
+         && (a-> param != b-> param) ) {        \
+      return False;                             \
+    }                                           \
+  } while ( 0 )
+
+#define MATCH_MINIMUM( param )                  \
+  do {                                          \
+    if ( (a-> param != GLX_DONT_CARE)           \
+         && (a-> param > b-> param) ) {         \
+      return False;                             \
+    }                                           \
+  } while ( 0 )
+
+#define MATCH_EXACT( param )                    \
+  do {                                          \
+    if ( a-> param != b-> param) {              \
+      return False;                             \
+    }                                           \
+  } while ( 0 )
+
+/**
+ * Determine if two GLXFBConfigs are compatible.
+ *
+ * \param a  Application specified config to test.
+ * \param b  Server specified config to test against \c a.
+ */
+static Bool
+fbconfigs_compatible(const __GLcontextModes * const a,
+                     const __GLcontextModes * const b)
+{
+   MATCH_DONT_CARE(doubleBufferMode);
+   MATCH_DONT_CARE(visualType);
+   MATCH_DONT_CARE(visualRating);
+   MATCH_DONT_CARE(xRenderable);
+   MATCH_DONT_CARE(fbconfigID);
+   MATCH_DONT_CARE(swapMethod);
+
+   MATCH_MINIMUM(rgbBits);
+   MATCH_MINIMUM(numAuxBuffers);
+   MATCH_MINIMUM(redBits);
+   MATCH_MINIMUM(greenBits);
+   MATCH_MINIMUM(blueBits);
+   MATCH_MINIMUM(alphaBits);
+   MATCH_MINIMUM(depthBits);
+   MATCH_MINIMUM(stencilBits);
+   MATCH_MINIMUM(accumRedBits);
+   MATCH_MINIMUM(accumGreenBits);
+   MATCH_MINIMUM(accumBlueBits);
+   MATCH_MINIMUM(accumAlphaBits);
+   MATCH_MINIMUM(sampleBuffers);
+   MATCH_MINIMUM(maxPbufferWidth);
+   MATCH_MINIMUM(maxPbufferHeight);
+   MATCH_MINIMUM(maxPbufferPixels);
+   MATCH_MINIMUM(samples);
+
+   MATCH_DONT_CARE(stereoMode);
+   MATCH_EXACT(level);
+
+   if (((a->drawableType & b->drawableType) == 0)
+       || ((a->renderType & b->renderType) == 0)) {
+      return False;
+   }
+
+
+   /* There is a bug in a few of the XFree86 DDX drivers.  They contain
+    * visuals with a "transparent type" of 0 when they really mean GLX_NONE.
+    * Technically speaking, it is a bug in the DDX driver, but there is
+    * enough of an installed base to work around the problem here.  In any
+    * case, 0 is not a valid value of the transparent type, so we'll treat 0
+    * from the app as GLX_DONT_CARE. We'll consider GLX_NONE from the app and
+    * 0 from the server to be a match to maintain backward compatibility with
+    * the (broken) drivers.
+    */
+
+   if (a->transparentPixel != GLX_DONT_CARE && a->transparentPixel != 0) {
+      if (a->transparentPixel == GLX_NONE) {
+         if (b->transparentPixel != GLX_NONE && b->transparentPixel != 0)
+            return False;
+      }
+      else {
+         MATCH_EXACT(transparentPixel);
+      }
+
+      switch (a->transparentPixel) {
+      case GLX_TRANSPARENT_RGB:
+         MATCH_DONT_CARE(transparentRed);
+         MATCH_DONT_CARE(transparentGreen);
+         MATCH_DONT_CARE(transparentBlue);
+         MATCH_DONT_CARE(transparentAlpha);
+         break;
+
+      case GLX_TRANSPARENT_INDEX:
+         MATCH_DONT_CARE(transparentIndex);
+         break;
+
+      default:
+         break;
+      }
+   }
+
+   return True;
+}
+
+
+/* There's some trickly language in the GLX spec about how this is supposed
+ * to work.  Basically, if a given component size is either not specified
+ * or the requested size is zero, it is supposed to act like PERFER_SMALLER.
+ * Well, that's really hard to do with the code as-is.  This behavior is
+ * closer to correct, but still not technically right.
+ */
+#define PREFER_LARGER_OR_ZERO(comp)             \
+  do {                                          \
+    if ( ((*a)-> comp) != ((*b)-> comp) ) {     \
+      if ( ((*a)-> comp) == 0 ) {               \
+        return -1;                              \
+      }                                         \
+      else if ( ((*b)-> comp) == 0 ) {          \
+        return 1;                               \
+      }                                         \
+      else {                                    \
+        return ((*b)-> comp) - ((*a)-> comp) ;  \
+      }                                         \
+    }                                           \
+  } while( 0 )
+
+#define PREFER_LARGER(comp)                     \
+  do {                                          \
+    if ( ((*a)-> comp) != ((*b)-> comp) ) {     \
+      return ((*b)-> comp) - ((*a)-> comp) ;    \
+    }                                           \
+  } while( 0 )
+
+#define PREFER_SMALLER(comp)                    \
+  do {                                          \
+    if ( ((*a)-> comp) != ((*b)-> comp) ) {     \
+      return ((*a)-> comp) - ((*b)-> comp) ;    \
+    }                                           \
+  } while( 0 )
+
+/**
+ * Compare two GLXFBConfigs.  This function is intended to be used as the
+ * compare function passed in to qsort.
+ *
+ * \returns If \c a is a "better" config, according to the specification of
+ *          SGIX_fbconfig, a number less than zero is returned.  If \c b is
+ *          better, then a number greater than zero is return.  If both are
+ *          equal, zero is returned.
+ * \sa qsort, glXChooseVisual, glXChooseFBConfig, glXChooseFBConfigSGIX
+ */
+static int
+fbconfig_compare(const __GLcontextModes * const *const a,
+                 const __GLcontextModes * const *const b)
+{
+   /* The order of these comparisons must NOT change.  It is defined by
+    * the GLX 1.3 spec and ARB_multisample.
+    */
+
+   PREFER_SMALLER(visualSelectGroup);
+
+   /* The sort order for the visualRating is GLX_NONE, GLX_SLOW, and
+    * GLX_NON_CONFORMANT_CONFIG.  It just so happens that this is the
+    * numerical sort order of the enums (0x8000, 0x8001, and 0x800D).
+    */
+   PREFER_SMALLER(visualRating);
+
+   /* This isn't quite right.  It is supposed to compare the sum of the
+    * components the user specifically set minimums for.
+    */
+   PREFER_LARGER_OR_ZERO(redBits);
+   PREFER_LARGER_OR_ZERO(greenBits);
+   PREFER_LARGER_OR_ZERO(blueBits);
+   PREFER_LARGER_OR_ZERO(alphaBits);
+
+   PREFER_SMALLER(rgbBits);
+
+   if (((*a)->doubleBufferMode != (*b)->doubleBufferMode)) {
+      /* Prefer single-buffer.
+       */
+      return (!(*a)->doubleBufferMode) ? -1 : 1;
+   }
+
+   PREFER_SMALLER(numAuxBuffers);
+
+   PREFER_LARGER_OR_ZERO(depthBits);
+   PREFER_SMALLER(stencilBits);
+
+   /* This isn't quite right.  It is supposed to compare the sum of the
+    * components the user specifically set minimums for.
+    */
+   PREFER_LARGER_OR_ZERO(accumRedBits);
+   PREFER_LARGER_OR_ZERO(accumGreenBits);
+   PREFER_LARGER_OR_ZERO(accumBlueBits);
+   PREFER_LARGER_OR_ZERO(accumAlphaBits);
+
+   PREFER_SMALLER(visualType);
+
+   /* None of the multisample specs say where this comparison should happen,
+    * so I put it near the end.
+    */
+   PREFER_SMALLER(sampleBuffers);
+   PREFER_SMALLER(samples);
+
+   /* None of the pbuffer or fbconfig specs say that this comparison needs
+    * to happen at all, but it seems like it should.
+    */
+   PREFER_LARGER(maxPbufferWidth);
+   PREFER_LARGER(maxPbufferHeight);
+   PREFER_LARGER(maxPbufferPixels);
+
+   return 0;
+}
+
+
+/**
+ * Selects and sorts a subset of the supplied configs based on the attributes.
+ * This function forms to basis of \c glXChooseVisual, \c glXChooseFBConfig,
+ * and \c glXChooseFBConfigSGIX.
+ *
+ * \param configs   Array of pointers to possible configs.  The elements of
+ *                  this array that do not meet the criteria will be set to
+ *                  NULL.  The remaining elements will be sorted according to
+ *                  the various visual / FBConfig selection rules.
+ * \param num_configs  Number of elements in the \c configs array.
+ * \param attribList   Attributes used select from \c configs.  This array is
+ *                     terminated by a \c None tag.  The array can either take
+ *                     the form expected by \c glXChooseVisual (where boolean
+ *                     tags do not have a value) or by \c glXChooseFBConfig
+ *                     (where every tag has a value).
+ * \param fbconfig_style_tags  Selects whether \c attribList is in
+ *                             \c glXChooseVisual style or
+ *                             \c glXChooseFBConfig style.
+ * \returns The number of valid elements left in \c configs.
+ *
+ * \sa glXChooseVisual, glXChooseFBConfig, glXChooseFBConfigSGIX
+ */
+static int
+choose_visual(__GLcontextModes ** configs, int num_configs,
+              const int *attribList, GLboolean fbconfig_style_tags)
+{
+   __GLcontextModes test_config;
+   int base;
+   int i;
+
+   /* This is a fairly direct implementation of the selection method
+    * described by GLX_SGIX_fbconfig.  Start by culling out all the
+    * configs that are not compatible with the selected parameter
+    * list.
+    */
+
+   init_fbconfig_for_chooser(&test_config, fbconfig_style_tags);
+   __glXInitializeVisualConfigFromTags(&test_config, 512,
+                                       (const INT32 *) attribList,
+                                       GL_TRUE, fbconfig_style_tags);
+
+   base = 0;
+   for (i = 0; i < num_configs; i++) {
+      if (fbconfigs_compatible(&test_config, configs[i])) {
+         configs[base] = configs[i];
+         base++;
+      }
+   }
+
+   if (base == 0) {
+      return 0;
+   }
+
+   if (base < num_configs) {
+      (void) memset(&configs[base], 0, sizeof(void *) * (num_configs - base));
+   }
+
+   /* After the incompatible configs are removed, the resulting
+    * list is sorted according to the rules set out in the various
+    * specifications.
+    */
+
+   qsort(configs, base, sizeof(__GLcontextModes *),
+         (int (*)(const void *, const void *)) fbconfig_compare);
+   return base;
+}
+
+
+
+
+/*
+** Return the visual that best matches the template.  Return None if no
+** visual matches the template.
+*/
+PUBLIC XVisualInfo *
+glXChooseVisual(Display * dpy, int screen, int *attribList)
+{
+   XVisualInfo *visualList = NULL;
+   __GLXdisplayPrivate *priv;
+   __GLXscreenConfigs *psc;
+   __GLcontextModes test_config;
+   __GLcontextModes *modes;
+   const __GLcontextModes *best_config = NULL;
+
+   /*
+    ** Get a list of all visuals, return if list is empty
+    */
+   if (GetGLXPrivScreenConfig(dpy, screen, &priv, &psc) != Success) {
+      return None;
+   }
+
+
+   /*
+    ** Build a template from the defaults and the attribute list
+    ** Free visual list and return if an unexpected token is encountered
+    */
+   init_fbconfig_for_chooser(&test_config, GL_FALSE);
+   __glXInitializeVisualConfigFromTags(&test_config, 512,
+                                       (const INT32 *) attribList,
+                                       GL_TRUE, GL_FALSE);
+
+   /*
+    ** Eliminate visuals that don't meet minimum requirements
+    ** Compute a score for those that do
+    ** Remember which visual, if any, got the highest score
+    ** If no visual is acceptable, return None
+    ** Otherwise, create an XVisualInfo list with just the selected X visual
+    ** and return this.
+    */
+   for (modes = psc->visuals; modes != NULL; modes = modes->next) {
+      if (fbconfigs_compatible(&test_config, modes)
+          && ((best_config == NULL)
+              ||
+              (fbconfig_compare
+               ((const __GLcontextModes * const *const) &modes,
+                &best_config) < 0))) {
+         XVisualInfo visualTemplate;
+         XVisualInfo *newList;
+         int i;
+
+         visualTemplate.screen = screen;
+         visualTemplate.visualid = modes->visualID;
+         newList = XGetVisualInfo(dpy, VisualScreenMask | VisualIDMask,
+                                  &visualTemplate, &i);
+
+         if (newList) {
+            Xfree(visualList);
+            visualList = newList;
+            best_config = modes;
+         }
+      }
+   }
+
+   return visualList;
+}
+
+
+PUBLIC const char *
+glXQueryExtensionsString(Display * dpy, int screen)
+{
+   __GLXscreenConfigs *psc;
+   __GLXdisplayPrivate *priv;
+
+   if (GetGLXPrivScreenConfig(dpy, screen, &priv, &psc) != Success) {
+      return NULL;
+   }
+
+   if (!psc->effectiveGLXexts) {
+      if (!psc->serverGLXexts) {
+         psc->serverGLXexts =
+            __glXQueryServerString(dpy, priv->majorOpcode, screen,
+                                   GLX_EXTENSIONS);
+      }
+
+      __glXCalculateUsableExtensions(psc,
+#ifdef GLX_DIRECT_RENDERING
+                                     (psc->driScreen != NULL),
+#else
+                                     GL_FALSE,
+#endif
+                                     priv->minorVersion);
+   }
+
+   return psc->effectiveGLXexts;
+}
+
+PUBLIC const char *
+glXGetClientString(Display * dpy, int name)
+{
+   switch (name) {
+   case GLX_VENDOR:
+      return (__glXGLXClientVendorName);
+   case GLX_VERSION:
+      return (__glXGLXClientVersion);
+   case GLX_EXTENSIONS:
+      return (__glXGetClientExtensions());
+   default:
+      return NULL;
+   }
+}
+
+PUBLIC const char *
+glXQueryServerString(Display * dpy, int screen, int name)
+{
+   __GLXscreenConfigs *psc;
+   __GLXdisplayPrivate *priv;
+   const char **str;
+
+
+   if (GetGLXPrivScreenConfig(dpy, screen, &priv, &psc) != Success) {
+      return NULL;
+   }
+
+   switch (name) {
+   case GLX_VENDOR:
+      str = &priv->serverGLXvendor;
+      break;
+   case GLX_VERSION:
+      str = &priv->serverGLXversion;
+      break;
+   case GLX_EXTENSIONS:
+      str = &psc->serverGLXexts;
+      break;
+   default:
+      return NULL;
+   }
+
+   if (*str == NULL) {
+      *str = __glXQueryServerString(dpy, priv->majorOpcode, screen, name);
+   }
+
+   return *str;
+}
+
+void
+__glXClientInfo(Display * dpy, int opcode)
+{
+   char *ext_str = __glXGetClientGLExtensionString();
+   int size = strlen(ext_str) + 1;
+
+#ifdef USE_XCB
+   xcb_connection_t *c = XGetXCBConnection(dpy);
+   xcb_glx_client_info(c,
+                       GLX_MAJOR_VERSION, GLX_MINOR_VERSION, size, ext_str);
+#else
+   xGLXClientInfoReq *req;
+
+   /* Send the glXClientInfo request */
+   LockDisplay(dpy);
+   GetReq(GLXClientInfo, req);
+   req->reqType = opcode;
+   req->glxCode = X_GLXClientInfo;
+   req->major = GLX_MAJOR_VERSION;
+   req->minor = GLX_MINOR_VERSION;
+
+   req->length += (size + 3) >> 2;
+   req->numbytes = size;
+   Data(dpy, ext_str, size);
+
+   UnlockDisplay(dpy);
+   SyncHandle();
+#endif /* USE_XCB */
+
+   Xfree(ext_str);
+}
+
+
+/*
+** EXT_import_context
+*/
+
+PUBLIC Display *
+glXGetCurrentDisplay(void)
+{
+   GLXContext gc = __glXGetCurrentContext();
+   if (NULL == gc)
+      return NULL;
+   return gc->currentDpy;
+}
+
+PUBLIC
+GLX_ALIAS(Display *, glXGetCurrentDisplayEXT, (void), (),
+          glXGetCurrentDisplay)
+
+/**
+ * Used internally by libGL to send \c xGLXQueryContextinfoExtReq requests
+ * to the X-server.
+ *
+ * \param dpy  Display where \c ctx was created.
+ * \param ctx  Context to query.
+ * \returns  \c Success on success.  \c GLX_BAD_CONTEXT if \c ctx is invalid,
+ *           or zero if the request failed due to internal problems (i.e.,
+ *           unable to allocate temporary memory, etc.)
+ *
+ * \note
+ * This function dynamically determines whether to use the EXT_import_context
+ * version of the protocol or the GLX 1.3 version of the protocol.
+ */
+static int __glXQueryContextInfo(Display * dpy, GLXContext ctx)
+{
+   __GLXdisplayPrivate *priv = __glXInitialize(dpy);
+   xGLXQueryContextReply reply;
+   CARD8 opcode;
+   GLuint numValues;
+   int retval;
+
+   if (ctx == NULL) {
+      return GLX_BAD_CONTEXT;
+   }
+   opcode = __glXSetupForCommand(dpy);
+   if (!opcode) {
+      return 0;
+   }
+
+   /* Send the glXQueryContextInfoEXT request */
+   LockDisplay(dpy);
+
+   if ((priv->majorVersion > 1) || (priv->minorVersion >= 3)) {
+      xGLXQueryContextReq *req;
+
+      GetReq(GLXQueryContext, req);
+
+      req->reqType = opcode;
+      req->glxCode = X_GLXQueryContext;
+      req->context = (unsigned int) (ctx->xid);
+   }
+   else {
+      xGLXVendorPrivateReq *vpreq;
+      xGLXQueryContextInfoEXTReq *req;
+
+      GetReqExtra(GLXVendorPrivate,
+                  sz_xGLXQueryContextInfoEXTReq - sz_xGLXVendorPrivateReq,
+                  vpreq);
+      req = (xGLXQueryContextInfoEXTReq *) vpreq;
+      req->reqType = opcode;
+      req->glxCode = X_GLXVendorPrivateWithReply;
+      req->vendorCode = X_GLXvop_QueryContextInfoEXT;
+      req->context = (unsigned int) (ctx->xid);
+   }
+
+   _XReply(dpy, (xReply *) & reply, 0, False);
+
+   numValues = reply.n;
+   if (numValues == 0)
+      retval = Success;
+   else if (numValues > __GLX_MAX_CONTEXT_PROPS)
+      retval = 0;
+   else {
+      int *propList, *pProp;
+      int nPropListBytes;
+      int i;
+
+      nPropListBytes = numValues << 3;
+      propList = (int *) Xmalloc(nPropListBytes);
+      if (NULL == propList) {
+         retval = 0;
+      }
+      else {
+         _XRead(dpy, (char *) propList, nPropListBytes);
+         pProp = propList;
+         for (i = 0; i < numValues; i++) {
+            switch (*pProp++) {
+            case GLX_SHARE_CONTEXT_EXT:
+               ctx->share_xid = *pProp++;
+               break;
+            case GLX_VISUAL_ID_EXT:
+               ctx->mode =
+                  _gl_context_modes_find_visual(ctx->psc->visuals, *pProp++);
+               break;
+            case GLX_SCREEN:
+               ctx->screen = *pProp++;
+               break;
+            case GLX_FBCONFIG_ID:
+               ctx->mode =
+                  _gl_context_modes_find_fbconfig(ctx->psc->configs,
+                                                  *pProp++);
+               break;
+            case GLX_RENDER_TYPE:
+               ctx->renderType = *pProp++;
+               break;
+            default:
+               pProp++;
+               continue;
+            }
+         }
+         Xfree((char *) propList);
+         retval = Success;
+      }
+   }
+   UnlockDisplay(dpy);
+   SyncHandle();
+   return retval;
+}
+
+PUBLIC int
+glXQueryContext(Display * dpy, GLXContext ctx, int attribute, int *value)
+{
+   int retVal;
+
+   /* get the information from the server if we don't have it already */
+#ifdef GLX_DIRECT_RENDERING
+   if (!ctx->driContext && (ctx->mode == NULL)) {
+#else
+   if (ctx->mode == NULL) {
+#endif
+      retVal = __glXQueryContextInfo(dpy, ctx);
+      if (Success != retVal)
+         return retVal;
+   }
+   switch (attribute) {
+   case GLX_SHARE_CONTEXT_EXT:
+      *value = (int) (ctx->share_xid);
+      break;
+   case GLX_VISUAL_ID_EXT:
+      *value = ctx->mode ? ctx->mode->visualID : None;
+      break;
+   case GLX_SCREEN:
+      *value = (int) (ctx->screen);
+      break;
+   case GLX_FBCONFIG_ID:
+      *value = ctx->mode ? ctx->mode->fbconfigID : None;
+      break;
+   case GLX_RENDER_TYPE:
+      *value = (int) (ctx->renderType);
+      break;
+   default:
+      return GLX_BAD_ATTRIBUTE;
+   }
+   return Success;
+}
+
+PUBLIC
+GLX_ALIAS(int, glXQueryContextInfoEXT,
+          (Display * dpy, GLXContext ctx, int attribute, int *value),
+          (dpy, ctx, attribute, value), glXQueryContext)
+
+PUBLIC GLXContextID glXGetContextIDEXT(const GLXContext ctx)
+{
+   return ctx->xid;
+}
+
+PUBLIC GLXContext
+glXImportContextEXT(Display * dpy, GLXContextID contextID)
+{
+   GLXContext ctx;
+
+   if (contextID == None) {
+      return NULL;
+   }
+   if (__glXIsDirect(dpy, contextID)) {
+      return NULL;
+   }
+
+   ctx = CreateContext(dpy, NULL, NULL, NULL, False, contextID, False, 0);
+   if (NULL != ctx) {
+      if (Success != __glXQueryContextInfo(dpy, ctx)) {
+         return NULL;
+      }
+   }
+   return ctx;
+}
+
+PUBLIC void
+glXFreeContextEXT(Display * dpy, GLXContext ctx)
+{
+   DestroyContext(dpy, ctx);
+}
+
+
+
+/*
+ * GLX 1.3 functions - these are just stubs for now!
+ */
+
+PUBLIC GLXFBConfig *
+glXChooseFBConfig(Display * dpy, int screen,
+                  const int *attribList, int *nitems)
+{
+   __GLcontextModes **config_list;
+   int list_size;
+
+
+   config_list = (__GLcontextModes **)
+      glXGetFBConfigs(dpy, screen, &list_size);
+
+   if ((config_list != NULL) && (list_size > 0) && (attribList != NULL)) {
+      list_size = choose_visual(config_list, list_size, attribList, GL_TRUE);
+      if (list_size == 0) {
+         XFree(config_list);
+         config_list = NULL;
+      }
+   }
+
+   *nitems = list_size;
+   return (GLXFBConfig *) config_list;
+}
+
+
+PUBLIC GLXContext
+glXCreateNewContext(Display * dpy, GLXFBConfig config,
+                    int renderType, GLXContext shareList, Bool allowDirect)
+{
+   return CreateContext(dpy, NULL, (__GLcontextModes *) config, shareList,
+                        allowDirect, None, True, renderType);
+}
+
+
+PUBLIC GLXDrawable
+glXGetCurrentReadDrawable(void)
+{
+   GLXContext gc = __glXGetCurrentContext();
+   return gc->currentReadable;
+}
+
+
+PUBLIC GLXFBConfig *
+glXGetFBConfigs(Display * dpy, int screen, int *nelements)
+{
+   __GLXdisplayPrivate *priv = __glXInitialize(dpy);
+   __GLcontextModes **config = NULL;
+   int i;
+
+   *nelements = 0;
+   if (priv && (priv->screenConfigs != NULL)
+       && (screen >= 0) && (screen <= ScreenCount(dpy))
+       && (priv->screenConfigs[screen].configs != NULL)
+       && (priv->screenConfigs[screen].configs->fbconfigID != GLX_DONT_CARE)) {
+      unsigned num_configs = 0;
+      __GLcontextModes *modes;
+
+
+      for (modes = priv->screenConfigs[screen].configs; modes != NULL;
+           modes = modes->next) {
+         if (modes->fbconfigID != GLX_DONT_CARE) {
+            num_configs++;
+         }
+      }
+
+      config = (__GLcontextModes **) Xmalloc(sizeof(__GLcontextModes *)
+                                             * num_configs);
+      if (config != NULL) {
+         *nelements = num_configs;
+         i = 0;
+         for (modes = priv->screenConfigs[screen].configs; modes != NULL;
+              modes = modes->next) {
+            if (modes->fbconfigID != GLX_DONT_CARE) {
+               config[i] = modes;
+               i++;
+            }
+         }
+      }
+   }
+   return (GLXFBConfig *) config;
+}
+
+
+PUBLIC int
+glXGetFBConfigAttrib(Display * dpy, GLXFBConfig config,
+                     int attribute, int *value)
+{
+   __GLcontextModes *const modes = ValidateGLXFBConfig(dpy, config);
+
+   return (modes != NULL)
+      ? _gl_get_context_mode_data(modes, attribute, value)
+      : GLXBadFBConfig;
+}
+
+
+PUBLIC XVisualInfo *
+glXGetVisualFromFBConfig(Display * dpy, GLXFBConfig config)
+{
+   XVisualInfo visualTemplate;
+   __GLcontextModes *fbconfig = (__GLcontextModes *) config;
+   int count;
+
+   /*
+    ** Get a list of all visuals, return if list is empty
+    */
+   visualTemplate.visualid = fbconfig->visualID;
+   return XGetVisualInfo(dpy, VisualIDMask, &visualTemplate, &count);
+}
+
+
+/*
+** GLX_SGI_swap_control
+*/
+static int
+__glXSwapIntervalSGI(int interval)
+{
+   xGLXVendorPrivateReq *req;
+   GLXContext gc = __glXGetCurrentContext();
+   __GLXscreenConfigs *psc;
+   Display *dpy;
+   CARD32 *interval_ptr;
+   CARD8 opcode;
+
+   if (gc == NULL) {
+      return GLX_BAD_CONTEXT;
+   }
+
+   if (interval <= 0) {
+      return GLX_BAD_VALUE;
+   }
+
+#ifdef __DRI_SWAP_CONTROL
+   if (gc->driContext) {
+      __GLXscreenConfigs * const psc = GetGLXScreenConfigs( gc->currentDpy,
+							    gc->screen );
+      __GLXDRIdrawable *pdraw = GetGLXDRIDrawable(gc->currentDpy,
+						  gc->currentDrawable,
+						  NULL);
+      if (psc->swapControl != NULL && pdraw != NULL) {
+	 psc->swapControl->setSwapInterval(pdraw->driDrawable, interval);
+	 return 0;
+      }
+      else if (pdraw == NULL) {
+	 return GLX_BAD_CONTEXT;
+      }
+   }
+#endif
+   psc = GetGLXScreenConfigs( gc->currentDpy, gc->screen);
+
+   if (gc->driContext && psc->driScreen && psc->driScreen->setSwapInterval) {
+      __GLXDRIdrawable *pdraw = GetGLXDRIDrawable(gc->currentDpy,
+						  gc->currentDrawable,
+						  NULL);
+      psc->driScreen->setSwapInterval(pdraw, interval);
+      return 0;
+   }
+
+   dpy = gc->currentDpy;
+   opcode = __glXSetupForCommand(dpy);
+   if (!opcode) {
+      return 0;
+   }
+
+   /* Send the glXSwapIntervalSGI request */
+   LockDisplay(dpy);
+   GetReqExtra(GLXVendorPrivate, sizeof(CARD32), req);
+   req->reqType = opcode;
+   req->glxCode = X_GLXVendorPrivate;
+   req->vendorCode = X_GLXvop_SwapIntervalSGI;
+   req->contextTag = gc->currentContextTag;
+
+   interval_ptr = (CARD32 *) (req + 1);
+   *interval_ptr = interval;
+
+   UnlockDisplay(dpy);
+   SyncHandle();
+   XFlush(dpy);
+
+   return 0;
+}
+
+
+/*
+** GLX_MESA_swap_control
+*/
+static int
+__glXSwapIntervalMESA(unsigned int interval)
+{
+   GLXContext gc = __glXGetCurrentContext();
+
+   if (interval < 0) {
+      return GLX_BAD_VALUE;
+   }
+
+#ifdef __DRI_SWAP_CONTROL
+   if (gc != NULL && gc->driContext) {
+      __GLXscreenConfigs *const psc = GetGLXScreenConfigs(gc->currentDpy,
+                                                          gc->screen);
+
+      if ((psc != NULL) && (psc->driScreen != NULL)) {
+         __GLXDRIdrawable *pdraw =
+            GetGLXDRIDrawable(gc->currentDpy, gc->currentDrawable, NULL);
+         if (psc->swapControl != NULL && pdraw != NULL) {
+            psc->swapControl->setSwapInterval(pdraw->driDrawable, interval);
+            return 0;
+         }
+      }
+   }
+#endif
+
+   if (gc != NULL && gc->driContext) {
+      __GLXscreenConfigs *psc;
+
+      psc = GetGLXScreenConfigs( gc->currentDpy, gc->screen);
+      if (psc->driScreen && psc->driScreen->setSwapInterval) {
+         __GLXDRIdrawable *pdraw = GetGLXDRIDrawable(gc->currentDpy,
+						     gc->currentDrawable, NULL);
+	 psc->driScreen->setSwapInterval(pdraw, interval);
+	 return 0;
+      }
+   }
+
+   return GLX_BAD_CONTEXT;
+}
+
+
+static int
+__glXGetSwapIntervalMESA(void)
+{
+#ifdef __DRI_SWAP_CONTROL
+   GLXContext gc = __glXGetCurrentContext();
+
+   if (gc != NULL && gc->driContext) {
+      __GLXscreenConfigs *const psc = GetGLXScreenConfigs(gc->currentDpy,
+                                                          gc->screen);
+
+      if ((psc != NULL) && (psc->driScreen != NULL)) {
+         __GLXDRIdrawable *pdraw =
+            GetGLXDRIDrawable(gc->currentDpy, gc->currentDrawable, NULL);
+         if (psc->swapControl != NULL && pdraw != NULL) {
+            return psc->swapControl->getSwapInterval(pdraw->driDrawable);
+         }
+      }
+   }
+#endif
+   if (gc != NULL && gc->driContext) {
+      __GLXscreenConfigs *psc;
+
+      psc = GetGLXScreenConfigs( gc->currentDpy, gc->screen);
+      if (psc->driScreen && psc->driScreen->getSwapInterval) {
+         __GLXDRIdrawable *pdraw = GetGLXDRIDrawable(gc->currentDpy,
+						     gc->currentDrawable, NULL);
+	 return psc->driScreen->getSwapInterval(pdraw);
+      }
+   }
+
+   return 0;
+}
+
+
+/*
+** GLX_MESA_swap_frame_usage
+*/
+
+static GLint
+__glXBeginFrameTrackingMESA(Display * dpy, GLXDrawable drawable)
+{
+   int status = GLX_BAD_CONTEXT;
+#ifdef __DRI_FRAME_TRACKING
+   int screen = 0;
+   __GLXDRIdrawable *pdraw = GetGLXDRIDrawable(dpy, drawable, &screen);
+   __GLXscreenConfigs *const psc = GetGLXScreenConfigs(dpy, screen);
+
+   if (pdraw != NULL && psc->frameTracking != NULL)
+      status = psc->frameTracking->frameTracking(pdraw->driDrawable, GL_TRUE);
+#else
+   (void) dpy;
+   (void) drawable;
+#endif
+   return status;
+}
+
+
+static GLint
+__glXEndFrameTrackingMESA(Display * dpy, GLXDrawable drawable)
+{
+   int status = GLX_BAD_CONTEXT;
+#ifdef __DRI_FRAME_TRACKING
+   int screen = 0;
+   __GLXDRIdrawable *pdraw = GetGLXDRIDrawable(dpy, drawable, &screen);
+   __GLXscreenConfigs *psc = GetGLXScreenConfigs(dpy, screen);
+
+   if (pdraw != NULL && psc->frameTracking != NULL)
+      status = psc->frameTracking->frameTracking(pdraw->driDrawable,
+                                                 GL_FALSE);
+#else
+   (void) dpy;
+   (void) drawable;
+#endif
+   return status;
+}
+
+
+static GLint
+__glXGetFrameUsageMESA(Display * dpy, GLXDrawable drawable, GLfloat * usage)
+{
+   int status = GLX_BAD_CONTEXT;
+#ifdef __DRI_FRAME_TRACKING
+   int screen = 0;
+   __GLXDRIdrawable *const pdraw = GetGLXDRIDrawable(dpy, drawable, &screen);
+   __GLXscreenConfigs *const psc = GetGLXScreenConfigs(dpy, screen);
+
+   if (pdraw != NULL && psc->frameTracking != NULL) {
+      int64_t sbc, missedFrames;
+      float lastMissedUsage;
+
+      status = psc->frameTracking->queryFrameTracking(pdraw->driDrawable,
+                                                      &sbc,
+                                                      &missedFrames,
+                                                      &lastMissedUsage,
+                                                      usage);
+   }
+#else
+   (void) dpy;
+   (void) drawable;
+   (void) usage;
+#endif
+   return status;
+}
+
+
+static GLint
+__glXQueryFrameTrackingMESA(Display * dpy, GLXDrawable drawable,
+                            int64_t * sbc, int64_t * missedFrames,
+                            GLfloat * lastMissedUsage)
+{
+   int status = GLX_BAD_CONTEXT;
+#ifdef __DRI_FRAME_TRACKING
+   int screen = 0;
+   __GLXDRIdrawable *pdraw = GetGLXDRIDrawable(dpy, drawable, &screen);
+   __GLXscreenConfigs *const psc = GetGLXScreenConfigs(dpy, screen);
+
+   if (pdraw != NULL && psc->frameTracking != NULL) {
+      float usage;
+
+      status = psc->frameTracking->queryFrameTracking(pdraw->driDrawable,
+                                                      sbc, missedFrames,
+                                                      lastMissedUsage,
+                                                      &usage);
+   }
+#else
+   (void) dpy;
+   (void) drawable;
+   (void) sbc;
+   (void) missedFrames;
+   (void) lastMissedUsage;
+#endif
+   return status;
+}
+
+
+/*
+** GLX_SGI_video_sync
+*/
+static int
+__glXGetVideoSyncSGI(unsigned int *count)
+{
+   int64_t ust, msc, sbc;
+   int ret;
+   GLXContext gc = __glXGetCurrentContext();
+   __GLXscreenConfigs *psc;
+   __GLXDRIdrawable *pdraw;
+
+   if (!gc || !gc->driContext)
+      return GLX_BAD_CONTEXT;
+
+   psc = GetGLXScreenConfigs(gc->currentDpy, gc->screen);
+   pdraw = GetGLXDRIDrawable(gc->currentDpy, gc->currentDrawable, NULL);
+
+   /* FIXME: Looking at the GLX_SGI_video_sync spec in the extension registry,
+    * FIXME: there should be a GLX encoding for this call.  I can find no
+    * FIXME: documentation for the GLX encoding.
+    */
+#ifdef __DRI_MEDIA_STREAM_COUNTER
+   if ( psc->msc && psc->driScreen ) {
+      ret = (*psc->msc->getDrawableMSC)(psc->__driScreen,
+					pdraw->driDrawable, &msc);
+      *count = (unsigned) msc;
+
+      return (ret == 0) ? 0 : GLX_BAD_CONTEXT;
+   }
+#endif
+   if (psc->driScreen && psc->driScreen->getDrawableMSC) {
+      ret = psc->driScreen->getDrawableMSC(psc, pdraw, &ust, &msc, &sbc);
+      *count = (unsigned) msc;
+      return (ret == True) ? 0 : GLX_BAD_CONTEXT;
+   }
+
+   return GLX_BAD_CONTEXT;
+}
+
+static int
+__glXWaitVideoSyncSGI(int divisor, int remainder, unsigned int *count)
+{
+   GLXContext gc = __glXGetCurrentContext();
+   __GLXscreenConfigs *psc;
+   __GLXDRIdrawable *pdraw;
+   int64_t ust, msc, sbc;
+   int ret;
+
+   if (divisor <= 0 || remainder < 0)
+      return GLX_BAD_VALUE;
+
+   if (!gc || !gc->driContext)
+      return GLX_BAD_CONTEXT;
+
+   psc = GetGLXScreenConfigs( gc->currentDpy, gc->screen);
+   pdraw = GetGLXDRIDrawable(gc->currentDpy, gc->currentDrawable, NULL);
+
+#ifdef __DRI_MEDIA_STREAM_COUNTER
+   if (psc->msc != NULL && psc->driScreen ) {
+      ret = (*psc->msc->waitForMSC)(pdraw->driDrawable, 0,
+				    divisor, remainder, &msc, &sbc);
+      *count = (unsigned) msc;
+      return (ret == 0) ? 0 : GLX_BAD_CONTEXT;
+   }
+#endif
+   if (psc->driScreen && psc->driScreen->waitForMSC) {
+      ret = psc->driScreen->waitForMSC(pdraw, 0, divisor, remainder, &ust, &msc,
+				       &sbc);
+      *count = (unsigned) msc;
+      return (ret == True) ? 0 : GLX_BAD_CONTEXT;
+   }
+
+   return GLX_BAD_CONTEXT;
+}
+
+
+/*
+** GLX_SGIX_fbconfig
+** Many of these functions are aliased to GLX 1.3 entry points in the 
+** GLX_functions table.
+*/
+
+PUBLIC
+GLX_ALIAS(int, glXGetFBConfigAttribSGIX,
+          (Display * dpy, GLXFBConfigSGIX config, int attribute, int *value),
+          (dpy, config, attribute, value), glXGetFBConfigAttrib)
+
+PUBLIC GLX_ALIAS(GLXFBConfigSGIX *, glXChooseFBConfigSGIX,
+                 (Display * dpy, int screen, int *attrib_list,
+                  int *nelements), (dpy, screen, attrib_list, nelements),
+                 glXChooseFBConfig)
+
+PUBLIC GLX_ALIAS(XVisualInfo *, glXGetVisualFromFBConfigSGIX,
+                 (Display * dpy, GLXFBConfigSGIX config),
+                 (dpy, config), glXGetVisualFromFBConfig)
+
+PUBLIC GLXPixmap
+glXCreateGLXPixmapWithConfigSGIX(Display * dpy,
+                                 GLXFBConfigSGIX config,
+                                 Pixmap pixmap)
+{
+   xGLXVendorPrivateWithReplyReq *vpreq;
+   xGLXCreateGLXPixmapWithConfigSGIXReq *req;
+   GLXPixmap xid = None;
+   CARD8 opcode;
+   const __GLcontextModes *const fbconfig = (__GLcontextModes *) config;
+   __GLXscreenConfigs *psc;
+
+
+   if ((dpy == NULL) || (config == NULL)) {
+      return None;
+   }
+
+   psc = GetGLXScreenConfigs(dpy, fbconfig->screen);
+   if ((psc != NULL)
+       && __glXExtensionBitIsEnabled(psc, SGIX_fbconfig_bit)) {
+      opcode = __glXSetupForCommand(dpy);
+      if (!opcode) {
+         return None;
+      }
+
+      /* Send the glXCreateGLXPixmapWithConfigSGIX request */
+      LockDisplay(dpy);
+      GetReqExtra(GLXVendorPrivateWithReply,
+                  sz_xGLXCreateGLXPixmapWithConfigSGIXReq -
+                  sz_xGLXVendorPrivateWithReplyReq, vpreq);
+      req = (xGLXCreateGLXPixmapWithConfigSGIXReq *) vpreq;
+      req->reqType = opcode;
+      req->glxCode = X_GLXVendorPrivateWithReply;
+      req->vendorCode = X_GLXvop_CreateGLXPixmapWithConfigSGIX;
+      req->screen = fbconfig->screen;
+      req->fbconfig = fbconfig->fbconfigID;
+      req->pixmap = pixmap;
+      req->glxpixmap = xid = XAllocID(dpy);
+      UnlockDisplay(dpy);
+      SyncHandle();
+   }
+
+   return xid;
+}
+
+PUBLIC GLXContext
+glXCreateContextWithConfigSGIX(Display * dpy,
+                               GLXFBConfigSGIX config, int renderType,
+                               GLXContext shareList, Bool allowDirect)
+{
+   GLXContext gc = NULL;
+   const __GLcontextModes *const fbconfig = (__GLcontextModes *) config;
+   __GLXscreenConfigs *psc;
+
+
+   if ((dpy == NULL) || (config == NULL)) {
+      return None;
+   }
+
+   psc = GetGLXScreenConfigs(dpy, fbconfig->screen);
+   if ((psc != NULL)
+       && __glXExtensionBitIsEnabled(psc, SGIX_fbconfig_bit)) {
+      gc = CreateContext(dpy, NULL, (__GLcontextModes *) config, shareList,
+                         allowDirect, None, False, renderType);
+   }
+
+   return gc;
+}
+
+
+PUBLIC GLXFBConfigSGIX
+glXGetFBConfigFromVisualSGIX(Display * dpy, XVisualInfo * vis)
+{
+   __GLXdisplayPrivate *priv;
+   __GLXscreenConfigs *psc = NULL;
+
+   if ((GetGLXPrivScreenConfig(dpy, vis->screen, &priv, &psc) != Success)
+       && __glXExtensionBitIsEnabled(psc, SGIX_fbconfig_bit)
+       && (psc->configs->fbconfigID != GLX_DONT_CARE)) {
+      return (GLXFBConfigSGIX) _gl_context_modes_find_visual(psc->configs,
+                                                             vis->visualid);
+   }
+
+   return NULL;
+}
+
+
+/*
+** GLX_SGIX_swap_group
+*/
+static void
+__glXJoinSwapGroupSGIX(Display * dpy, GLXDrawable drawable,
+                       GLXDrawable member)
+{
+   (void) dpy;
+   (void) drawable;
+   (void) member;
+}
+
+
+/*
+** GLX_SGIX_swap_barrier
+*/
+static void
+__glXBindSwapBarrierSGIX(Display * dpy, GLXDrawable drawable, int barrier)
+{
+   (void) dpy;
+   (void) drawable;
+   (void) barrier;
+}
+
+static Bool
+__glXQueryMaxSwapBarriersSGIX(Display * dpy, int screen, int *max)
+{
+   (void) dpy;
+   (void) screen;
+   (void) max;
+   return False;
+}
+
+
+/*
+** GLX_OML_sync_control
+*/
+static Bool
+__glXGetSyncValuesOML(Display * dpy, GLXDrawable drawable,
+                      int64_t * ust, int64_t * msc, int64_t * sbc)
+{
+   __GLXdisplayPrivate * const priv = __glXInitialize(dpy);
+   int i, ret;
+   __GLXDRIdrawable *pdraw;
+   __GLXscreenConfigs *psc;
+
+   if (!priv)
+      return False;
+
+   pdraw = GetGLXDRIDrawable(dpy, drawable, &i);
+   psc = &priv->screenConfigs[i];
+
+#if defined(__DRI_SWAP_BUFFER_COUNTER) && defined(__DRI_MEDIA_STREAM_COUNTER)
+   if (pdraw && psc->sbc && psc->sbc)
+      return ( (pdraw && psc->sbc && psc->msc)
+	       && ((*psc->msc->getMSC)(psc->driScreen, msc) == 0)
+	       && ((*psc->sbc->getSBC)(pdraw->driDrawable, sbc) == 0)
+	       && (__glXGetUST(ust) == 0) );
+#endif
+   if (pdraw && psc && psc->driScreen && psc->driScreen->getDrawableMSC) {
+      ret = psc->driScreen->getDrawableMSC(psc, pdraw, ust, msc, sbc);
+      return ret;
+   }
+
+   return False;
+}
+
+#ifdef GLX_DIRECT_RENDERING
+_X_HIDDEN GLboolean
+__driGetMscRateOML(__DRIdrawable * draw,
+                   int32_t * numerator, int32_t * denominator, void *private)
+{
+#ifdef XF86VIDMODE
+   __GLXscreenConfigs *psc;
+   XF86VidModeModeLine mode_line;
+   int dot_clock;
+   int i;
+   __GLXDRIdrawable *glxDraw = private;
+
+   psc = glxDraw->psc;
+   if (XF86VidModeQueryVersion(psc->dpy, &i, &i) &&
+       XF86VidModeGetModeLine(psc->dpy, psc->scr, &dot_clock, &mode_line)) {
+      unsigned n = dot_clock * 1000;
+      unsigned d = mode_line.vtotal * mode_line.htotal;
+
+# define V_INTERLACE 0x010
+# define V_DBLSCAN   0x020
+
+      if (mode_line.flags & V_INTERLACE)
+         n *= 2;
+      else if (mode_line.flags & V_DBLSCAN)
+         d *= 2;
+
+      /* The OML_sync_control spec requires that if the refresh rate is a
+       * whole number, that the returned numerator be equal to the refresh
+       * rate and the denominator be 1.
+       */
+
+      if (n % d == 0) {
+         n /= d;
+         d = 1;
+      }
+      else {
+         static const unsigned f[] = { 13, 11, 7, 5, 3, 2, 0 };
+
+         /* This is a poor man's way to reduce a fraction.  It's far from
+          * perfect, but it will work well enough for this situation.
+          */
+
+         for (i = 0; f[i] != 0; i++) {
+            while (n % f[i] == 0 && d % f[i] == 0) {
+               d /= f[i];
+               n /= f[i];
+            }
+         }
+      }
+
+      *numerator = n;
+      *denominator = d;
+
+      return True;
+   }
+   else
+      return False;
+#else
+   return False;
+#endif
+}
+#endif
+
+/**
+ * Determine the refresh rate of the specified drawable and display.
+ *
+ * \param dpy          Display whose refresh rate is to be determined.
+ * \param drawable     Drawable whose refresh rate is to be determined.
+ * \param numerator    Numerator of the refresh rate.
+ * \param demoninator  Denominator of the refresh rate.
+ * \return  If the refresh rate for the specified display and drawable could
+ *          be calculated, True is returned.  Otherwise False is returned.
+ *
+ * \note This function is implemented entirely client-side.  A lot of other
+ *       functionality is required to export GLX_OML_sync_control, so on
+ *       XFree86 this function can be called for direct-rendering contexts
+ *       when GLX_OML_sync_control appears in the client extension string.
+ */
+
+_X_HIDDEN GLboolean
+__glXGetMscRateOML(Display * dpy, GLXDrawable drawable,
+                   int32_t * numerator, int32_t * denominator)
+{
+#if defined( GLX_DIRECT_RENDERING ) && defined( XF86VIDMODE )
+   __GLXDRIdrawable *draw = GetGLXDRIDrawable(dpy, drawable, NULL);
+
+   if (draw == NULL)
+      return False;
+
+   return __driGetMscRateOML(draw->driDrawable, numerator, denominator, draw);
+#else
+   (void) dpy;
+   (void) drawable;
+   (void) numerator;
+   (void) denominator;
+#endif
+   return False;
+}
+
+
+static int64_t
+__glXSwapBuffersMscOML(Display * dpy, GLXDrawable drawable,
+                       int64_t target_msc, int64_t divisor, int64_t remainder)
+{
+   GLXContext gc = __glXGetCurrentContext();
+   int screen;
+   __GLXDRIdrawable *pdraw = GetGLXDRIDrawable(dpy, drawable, &screen);
+   __GLXscreenConfigs *const psc = GetGLXScreenConfigs(dpy, screen);
+
+   if (!pdraw || !gc->driContext) /* no GLX for this */
+      return -1;
+
+   /* The OML_sync_control spec says these should "generate a GLX_BAD_VALUE
+    * error", but it also says "It [glXSwapBuffersMscOML] will return a value
+    * of -1 if the function failed because of errors detected in the input
+    * parameters"
+    */
+   if (divisor < 0 || remainder < 0 || target_msc < 0)
+      return -1;
+   if (divisor > 0 && remainder >= divisor)
+      return -1;
+
+#ifdef __DRI_SWAP_BUFFER_COUNTER
+   if (psc->counters != NULL)
+      return (*psc->sbc->swapBuffersMSC)(pdraw->driDrawable, target_msc,
+					 divisor, remainder);
+#endif
+
+#ifdef GLX_DIRECT_RENDERING
+   if (psc->driScreen && psc->driScreen->swapBuffers)
+      return (*psc->driScreen->swapBuffers)(pdraw, target_msc, divisor,
+					    remainder);
+#endif
+
+   return -1;
+}
+
+
+static Bool
+__glXWaitForMscOML(Display * dpy, GLXDrawable drawable,
+                   int64_t target_msc, int64_t divisor,
+                   int64_t remainder, int64_t * ust,
+                   int64_t * msc, int64_t * sbc)
+{
+   int screen;
+   __GLXDRIdrawable *pdraw = GetGLXDRIDrawable(dpy, drawable, &screen);
+   __GLXscreenConfigs * const psc = GetGLXScreenConfigs( dpy, screen );
+   int ret;
+
+   fprintf(stderr, "waitmsc: %lld, %lld, %lld\n", target_msc, divisor,
+	   remainder);
+
+   /* The OML_sync_control spec says these should "generate a GLX_BAD_VALUE
+    * error", but the return type in the spec is Bool.
+    */
+   if (divisor < 0 || remainder < 0 || target_msc < 0)
+      return False;
+   if (divisor > 0 && remainder >= divisor)
+      return False;
+
+#ifdef __DRI_MEDIA_STREAM_COUNTER
+   if (pdraw != NULL && psc->msc != NULL) {
+      fprintf(stderr, "dri1 msc\n");
+      ret = (*psc->msc->waitForMSC) (pdraw->driDrawable, target_msc,
+                                     divisor, remainder, msc, sbc);
+
+      /* __glXGetUST returns zero on success and non-zero on failure.
+       * This function returns True on success and False on failure.
+       */
+      return ((ret == 0) && (__glXGetUST(ust) == 0));
+   }
+#endif
+   if (pdraw && psc->driScreen && psc->driScreen->waitForMSC) {
+      ret = psc->driScreen->waitForMSC(pdraw, target_msc, divisor, remainder,
+				       ust, msc, sbc);
+      return ret;
+   }
+
+   fprintf(stderr, "no drawable??\n");
+   return False;
+}
+
+
+static Bool
+__glXWaitForSbcOML(Display * dpy, GLXDrawable drawable,
+                   int64_t target_sbc, int64_t * ust,
+                   int64_t * msc, int64_t * sbc)
+{
+   int screen;
+   __GLXDRIdrawable *pdraw = GetGLXDRIDrawable(dpy, drawable, &screen);
+   __GLXscreenConfigs *const psc = GetGLXScreenConfigs(dpy, screen);
+   int ret;
+
+   /* The OML_sync_control spec says this should "generate a GLX_BAD_VALUE
+    * error", but the return type in the spec is Bool.
+    */
+   if (target_sbc < 0)
+      return False;
+#ifdef __DRI_SWAP_BUFFER_COUNTER
+   if (pdraw != NULL && psc->sbc != NULL) {
+      ret =
+         (*psc->sbc->waitForSBC) (pdraw->driDrawable, target_sbc, msc, sbc);
+
+      /* __glXGetUST returns zero on success and non-zero on failure.
+       * This function returns True on success and False on failure.
+       */
+      return ((ret == 0) && (__glXGetUST(ust) == 0));
+   }
+#endif
+   if (pdraw && psc->driScreen && psc->driScreen->waitForMSC) {
+      ret = psc->driScreen->waitForSBC(pdraw, target_sbc, ust, msc, sbc);
+      return ret;
+   }
+   return False;
+}
+
+
+/**
+ * GLX_MESA_allocate_memory
+ */
+/*@{*/
+
+PUBLIC void *
+glXAllocateMemoryMESA(Display * dpy, int scrn,
+                      size_t size, float readFreq,
+                      float writeFreq, float priority)
+{
+#ifdef __DRI_ALLOCATE
+   __GLXscreenConfigs *const psc = GetGLXScreenConfigs(dpy, scrn);
+
+   if (psc && psc->allocate)
+      return (*psc->allocate->allocateMemory) (psc->__driScreen, size,
+                                               readFreq, writeFreq, priority);
+
+#else
+   (void) dpy;
+   (void) scrn;
+   (void) size;
+   (void) readFreq;
+   (void) writeFreq;
+   (void) priority;
+#endif /* __DRI_ALLOCATE */
+
+   return NULL;
+}
+
+
+PUBLIC void
+glXFreeMemoryMESA(Display * dpy, int scrn, void *pointer)
+{
+#ifdef __DRI_ALLOCATE
+   __GLXscreenConfigs *const psc = GetGLXScreenConfigs(dpy, scrn);
+
+   if (psc && psc->allocate)
+      (*psc->allocate->freeMemory) (psc->__driScreen, pointer);
+
+#else
+   (void) dpy;
+   (void) scrn;
+   (void) pointer;
+#endif /* __DRI_ALLOCATE */
+}
+
+
+PUBLIC GLuint
+glXGetMemoryOffsetMESA(Display * dpy, int scrn, const void *pointer)
+{
+#ifdef __DRI_ALLOCATE
+   __GLXscreenConfigs *const psc = GetGLXScreenConfigs(dpy, scrn);
+
+   if (psc && psc->allocate)
+      return (*psc->allocate->memoryOffset) (psc->__driScreen, pointer);
+
+#else
+   (void) dpy;
+   (void) scrn;
+   (void) pointer;
+#endif /* GLX_DIRECT_RENDERING */
+
+   return ~0L;
+}
+
+/*@}*/
+
+
+/**
+ * Mesa extension stubs.  These will help reduce portability problems.
+ */
+/*@{*/
+
+/**
+ * Release all buffers associated with the specified GLX drawable.
+ *
+ * \todo
+ * This function was intended for stand-alone Mesa.  The issue there is that
+ * the library doesn't get any notification when a window is closed.  In
+ * DRI there is a similar but slightly different issue.  When GLX 1.3 is
+ * supported, there are 3 different functions to destroy a drawable.  It
+ * should be possible to create GLX protocol (or have it determine which
+ * protocol to use based on the type of the drawable) to have one function
+ * do the work of 3.  For the direct-rendering case, this function could
+ * just call the driver's \c __DRIdrawableRec::destroyDrawable function.
+ * This would reduce the frequency with which \c __driGarbageCollectDrawables
+ * would need to be used.  This really should be done as part of the new DRI
+ * interface work.
+ *
+ * \sa http://oss.sgi.com/projects/ogl-sample/registry/MESA/release_buffers.txt
+ *     __driGarbageCollectDrawables
+ *     glXDestroyGLXPixmap
+ *     glXDestroyPbuffer glXDestroyPixmap glXDestroyWindow
+ *     glXDestroyGLXPbufferSGIX glXDestroyGLXVideoSourceSGIX
+ */
+static Bool
+__glXReleaseBuffersMESA(Display * dpy, GLXDrawable d)
+{
+   (void) dpy;
+   (void) d;
+   return False;
+}
+
+
+PUBLIC GLXPixmap
+glXCreateGLXPixmapMESA(Display * dpy, XVisualInfo * visual,
+                       Pixmap pixmap, Colormap cmap)
+{
+   (void) dpy;
+   (void) visual;
+   (void) pixmap;
+   (void) cmap;
+   return 0;
+}
+
+/*@}*/
+
+
+/**
+ * GLX_MESA_copy_sub_buffer
+ */
+#define X_GLXvop_CopySubBufferMESA 5154 /* temporary */
+static void
+__glXCopySubBufferMESA(Display * dpy, GLXDrawable drawable,
+                       int x, int y, int width, int height)
+{
+   xGLXVendorPrivateReq *req;
+   GLXContext gc;
+   GLXContextTag tag;
+   CARD32 *drawable_ptr;
+   INT32 *x_ptr, *y_ptr, *w_ptr, *h_ptr;
+   CARD8 opcode;
+
+#ifdef __DRI_COPY_SUB_BUFFER
+   int screen;
+   __GLXDRIdrawable *pdraw = GetGLXDRIDrawable(dpy, drawable, &screen);
+   if (pdraw != NULL) {
+      __GLXscreenConfigs *const psc = GetGLXScreenConfigs(dpy, screen);
+      if (psc->driScreen->copySubBuffer != NULL) {
+         glFlush();
+         (*psc->driScreen->copySubBuffer) (pdraw, x, y, width, height);
+      }
+
+      return;
+   }
+#endif
+
+   opcode = __glXSetupForCommand(dpy);
+   if (!opcode)
+      return;
+
+   /*
+    ** The calling thread may or may not have a current context.  If it
+    ** does, send the context tag so the server can do a flush.
+    */
+   gc = __glXGetCurrentContext();
+   if ((gc != NULL) && (dpy == gc->currentDpy) &&
+       ((drawable == gc->currentDrawable) ||
+        (drawable == gc->currentReadable))) {
+      tag = gc->currentContextTag;
+   }
+   else {
+      tag = 0;
+   }
+
+   LockDisplay(dpy);
+   GetReqExtra(GLXVendorPrivate, sizeof(CARD32) + sizeof(INT32) * 4, req);
+   req->reqType = opcode;
+   req->glxCode = X_GLXVendorPrivate;
+   req->vendorCode = X_GLXvop_CopySubBufferMESA;
+   req->contextTag = tag;
+
+   drawable_ptr = (CARD32 *) (req + 1);
+   x_ptr = (INT32 *) (drawable_ptr + 1);
+   y_ptr = (INT32 *) (drawable_ptr + 2);
+   w_ptr = (INT32 *) (drawable_ptr + 3);
+   h_ptr = (INT32 *) (drawable_ptr + 4);
+
+   *drawable_ptr = drawable;
+   *x_ptr = x;
+   *y_ptr = y;
+   *w_ptr = width;
+   *h_ptr = height;
+
+   UnlockDisplay(dpy);
+   SyncHandle();
+}
+
+
+/**
+ * GLX_EXT_texture_from_pixmap
+ */
+/*@{*/
+static void
+__glXBindTexImageEXT(Display * dpy,
+                     GLXDrawable drawable, int buffer, const int *attrib_list)
+{
+   xGLXVendorPrivateReq *req;
+   GLXContext gc = __glXGetCurrentContext();
+   CARD32 *drawable_ptr;
+   INT32 *buffer_ptr;
+   CARD32 *num_attrib_ptr;
+   CARD32 *attrib_ptr;
+   CARD8 opcode;
+   unsigned int i;
+
+   if (gc == NULL)
+      return;
+
+   i = 0;
+   if (attrib_list) {
+      while (attrib_list[i * 2] != None)
+         i++;
+   }
+
+#ifdef GLX_DIRECT_RENDERING
+   if (gc->driContext) {
+      __GLXDRIdrawable *pdraw = GetGLXDRIDrawable(dpy, drawable, NULL);
+
+      if (pdraw != NULL) {
+         if (pdraw->psc->texBuffer->base.version >= 2 &&
+             pdraw->psc->texBuffer->setTexBuffer2 != NULL) {
+            (*pdraw->psc->texBuffer->setTexBuffer2) (gc->__driContext,
+                                                     pdraw->textureTarget,
+                                                     pdraw->textureFormat,
+                                                     pdraw->driDrawable);
+         }
+         else {
+            (*pdraw->psc->texBuffer->setTexBuffer) (gc->__driContext,
+                                                    pdraw->textureTarget,
+                                                    pdraw->driDrawable);
+         }
+      }
+      return;
+   }
+#endif
+
+   opcode = __glXSetupForCommand(dpy);
+   if (!opcode)
+      return;
+
+   LockDisplay(dpy);
+   GetReqExtra(GLXVendorPrivate, 12 + 8 * i, req);
+   req->reqType = opcode;
+   req->glxCode = X_GLXVendorPrivate;
+   req->vendorCode = X_GLXvop_BindTexImageEXT;
+   req->contextTag = gc->currentContextTag;
+
+   drawable_ptr = (CARD32 *) (req + 1);
+   buffer_ptr = (INT32 *) (drawable_ptr + 1);
+   num_attrib_ptr = (CARD32 *) (buffer_ptr + 1);
+   attrib_ptr = (CARD32 *) (num_attrib_ptr + 1);
+
+   *drawable_ptr = drawable;
+   *buffer_ptr = buffer;
+   *num_attrib_ptr = (CARD32) i;
+
+   i = 0;
+   if (attrib_list) {
+      while (attrib_list[i * 2] != None) {
+         *attrib_ptr++ = (CARD32) attrib_list[i * 2 + 0];
+         *attrib_ptr++ = (CARD32) attrib_list[i * 2 + 1];
+         i++;
+      }
+   }
+
+   UnlockDisplay(dpy);
+   SyncHandle();
+}
+
+static void
+__glXReleaseTexImageEXT(Display * dpy, GLXDrawable drawable, int buffer)
+{
+   xGLXVendorPrivateReq *req;
+   GLXContext gc = __glXGetCurrentContext();
+   CARD32 *drawable_ptr;
+   INT32 *buffer_ptr;
+   CARD8 opcode;
+
+   if (gc == NULL)
+      return;
+
+#ifdef GLX_DIRECT_RENDERING
+   if (gc->driContext)
+      return;
+#endif
+
+   opcode = __glXSetupForCommand(dpy);
+   if (!opcode)
+      return;
+
+   LockDisplay(dpy);
+   GetReqExtra(GLXVendorPrivate, sizeof(CARD32) + sizeof(INT32), req);
+   req->reqType = opcode;
+   req->glxCode = X_GLXVendorPrivate;
+   req->vendorCode = X_GLXvop_ReleaseTexImageEXT;
+   req->contextTag = gc->currentContextTag;
+
+   drawable_ptr = (CARD32 *) (req + 1);
+   buffer_ptr = (INT32 *) (drawable_ptr + 1);
+
+   *drawable_ptr = drawable;
+   *buffer_ptr = buffer;
+
+   UnlockDisplay(dpy);
+   SyncHandle();
+}
+
+/*@}*/
+
+/**
+ * \c strdup is actually not a standard ANSI C or POSIX routine.
+ * Irix will not define it if ANSI mode is in effect.
+ *
+ * \sa strdup
+ */
+_X_HIDDEN char *
+__glXstrdup(const char *str)
+{
+   char *copy;
+   copy = (char *) Xmalloc(strlen(str) + 1);
+   if (!copy)
+      return NULL;
+   strcpy(copy, str);
+   return copy;
+}
+
+/*
+** glXGetProcAddress support
+*/
+
+struct name_address_pair
+{
+   const char *Name;
+   GLvoid *Address;
+};
+
+#define GLX_FUNCTION(f) { # f, (GLvoid *) f }
+#define GLX_FUNCTION2(n,f) { # n, (GLvoid *) f }
+
+static const struct name_address_pair GLX_functions[] = {
+   /*** GLX_VERSION_1_0 ***/
+   GLX_FUNCTION(glXChooseVisual),
+   GLX_FUNCTION(glXCopyContext),
+   GLX_FUNCTION(glXCreateContext),
+   GLX_FUNCTION(glXCreateGLXPixmap),
+   GLX_FUNCTION(glXDestroyContext),
+   GLX_FUNCTION(glXDestroyGLXPixmap),
+   GLX_FUNCTION(glXGetConfig),
+   GLX_FUNCTION(glXGetCurrentContext),
+   GLX_FUNCTION(glXGetCurrentDrawable),
+   GLX_FUNCTION(glXIsDirect),
+   GLX_FUNCTION(glXMakeCurrent),
+   GLX_FUNCTION(glXQueryExtension),
+   GLX_FUNCTION(glXQueryVersion),
+   GLX_FUNCTION(glXSwapBuffers),
+   GLX_FUNCTION(glXUseXFont),
+   GLX_FUNCTION(glXWaitGL),
+   GLX_FUNCTION(glXWaitX),
+
+   /*** GLX_VERSION_1_1 ***/
+   GLX_FUNCTION(glXGetClientString),
+   GLX_FUNCTION(glXQueryExtensionsString),
+   GLX_FUNCTION(glXQueryServerString),
+
+   /*** GLX_VERSION_1_2 ***/
+   GLX_FUNCTION(glXGetCurrentDisplay),
+
+   /*** GLX_VERSION_1_3 ***/
+   GLX_FUNCTION(glXChooseFBConfig),
+   GLX_FUNCTION(glXCreateNewContext),
+   GLX_FUNCTION(glXCreatePbuffer),
+   GLX_FUNCTION(glXCreatePixmap),
+   GLX_FUNCTION(glXCreateWindow),
+   GLX_FUNCTION(glXDestroyPbuffer),
+   GLX_FUNCTION(glXDestroyPixmap),
+   GLX_FUNCTION(glXDestroyWindow),
+   GLX_FUNCTION(glXGetCurrentReadDrawable),
+   GLX_FUNCTION(glXGetFBConfigAttrib),
+   GLX_FUNCTION(glXGetFBConfigs),
+   GLX_FUNCTION(glXGetSelectedEvent),
+   GLX_FUNCTION(glXGetVisualFromFBConfig),
+   GLX_FUNCTION(glXMakeContextCurrent),
+   GLX_FUNCTION(glXQueryContext),
+   GLX_FUNCTION(glXQueryDrawable),
+   GLX_FUNCTION(glXSelectEvent),
+
+   /*** GLX_SGI_swap_control ***/
+   GLX_FUNCTION2(glXSwapIntervalSGI, __glXSwapIntervalSGI),
+
+   /*** GLX_SGI_video_sync ***/
+   GLX_FUNCTION2(glXGetVideoSyncSGI, __glXGetVideoSyncSGI),
+   GLX_FUNCTION2(glXWaitVideoSyncSGI, __glXWaitVideoSyncSGI),
+
+   /*** GLX_SGI_make_current_read ***/
+   GLX_FUNCTION2(glXMakeCurrentReadSGI, glXMakeContextCurrent),
+   GLX_FUNCTION2(glXGetCurrentReadDrawableSGI, glXGetCurrentReadDrawable),
+
+   /*** GLX_EXT_import_context ***/
+   GLX_FUNCTION(glXFreeContextEXT),
+   GLX_FUNCTION(glXGetContextIDEXT),
+   GLX_FUNCTION2(glXGetCurrentDisplayEXT, glXGetCurrentDisplay),
+   GLX_FUNCTION(glXImportContextEXT),
+   GLX_FUNCTION2(glXQueryContextInfoEXT, glXQueryContext),
+
+   /*** GLX_SGIX_fbconfig ***/
+   GLX_FUNCTION2(glXGetFBConfigAttribSGIX, glXGetFBConfigAttrib),
+   GLX_FUNCTION2(glXChooseFBConfigSGIX, glXChooseFBConfig),
+   GLX_FUNCTION(glXCreateGLXPixmapWithConfigSGIX),
+   GLX_FUNCTION(glXCreateContextWithConfigSGIX),
+   GLX_FUNCTION2(glXGetVisualFromFBConfigSGIX, glXGetVisualFromFBConfig),
+   GLX_FUNCTION(glXGetFBConfigFromVisualSGIX),
+
+   /*** GLX_SGIX_pbuffer ***/
+   GLX_FUNCTION(glXCreateGLXPbufferSGIX),
+   GLX_FUNCTION(glXDestroyGLXPbufferSGIX),
+   GLX_FUNCTION(glXQueryGLXPbufferSGIX),
+   GLX_FUNCTION(glXSelectEventSGIX),
+   GLX_FUNCTION(glXGetSelectedEventSGIX),
+
+   /*** GLX_SGIX_swap_group ***/
+   GLX_FUNCTION2(glXJoinSwapGroupSGIX, __glXJoinSwapGroupSGIX),
+
+   /*** GLX_SGIX_swap_barrier ***/
+   GLX_FUNCTION2(glXBindSwapBarrierSGIX, __glXBindSwapBarrierSGIX),
+   GLX_FUNCTION2(glXQueryMaxSwapBarriersSGIX, __glXQueryMaxSwapBarriersSGIX),
+
+   /*** GLX_MESA_allocate_memory ***/
+   GLX_FUNCTION(glXAllocateMemoryMESA),
+   GLX_FUNCTION(glXFreeMemoryMESA),
+   GLX_FUNCTION(glXGetMemoryOffsetMESA),
+
+   /*** GLX_MESA_copy_sub_buffer ***/
+   GLX_FUNCTION2(glXCopySubBufferMESA, __glXCopySubBufferMESA),
+
+   /*** GLX_MESA_pixmap_colormap ***/
+   GLX_FUNCTION(glXCreateGLXPixmapMESA),
+
+   /*** GLX_MESA_release_buffers ***/
+   GLX_FUNCTION2(glXReleaseBuffersMESA, __glXReleaseBuffersMESA),
+
+   /*** GLX_MESA_swap_control ***/
+   GLX_FUNCTION2(glXSwapIntervalMESA, __glXSwapIntervalMESA),
+   GLX_FUNCTION2(glXGetSwapIntervalMESA, __glXGetSwapIntervalMESA),
+
+   /*** GLX_MESA_swap_frame_usage ***/
+   GLX_FUNCTION2(glXBeginFrameTrackingMESA, __glXBeginFrameTrackingMESA),
+   GLX_FUNCTION2(glXEndFrameTrackingMESA, __glXEndFrameTrackingMESA),
+   GLX_FUNCTION2(glXGetFrameUsageMESA, __glXGetFrameUsageMESA),
+   GLX_FUNCTION2(glXQueryFrameTrackingMESA, __glXQueryFrameTrackingMESA),
+
+   /*** GLX_ARB_get_proc_address ***/
+   GLX_FUNCTION(glXGetProcAddressARB),
+
+   /*** GLX 1.4 ***/
+   GLX_FUNCTION2(glXGetProcAddress, glXGetProcAddressARB),
+
+   /*** GLX_OML_sync_control ***/
+   GLX_FUNCTION2(glXWaitForSbcOML, __glXWaitForSbcOML),
+   GLX_FUNCTION2(glXWaitForMscOML, __glXWaitForMscOML),
+   GLX_FUNCTION2(glXSwapBuffersMscOML, __glXSwapBuffersMscOML),
+   GLX_FUNCTION2(glXGetMscRateOML, __glXGetMscRateOML),
+   GLX_FUNCTION2(glXGetSyncValuesOML, __glXGetSyncValuesOML),
+
+   /*** GLX_EXT_texture_from_pixmap ***/
+   GLX_FUNCTION2(glXBindTexImageEXT, __glXBindTexImageEXT),
+   GLX_FUNCTION2(glXReleaseTexImageEXT, __glXReleaseTexImageEXT),
+
+#ifdef GLX_DIRECT_RENDERING
+   /*** DRI configuration ***/
+   GLX_FUNCTION(glXGetScreenDriver),
+   GLX_FUNCTION(glXGetDriverConfig),
+#endif
+
+   {NULL, NULL}                 /* end of list */
+};
+
+
+static const GLvoid *
+get_glx_proc_address(const char *funcName)
+{
+   GLuint i;
+
+   /* try static functions */
+   for (i = 0; GLX_functions[i].Name; i++) {
+      if (strcmp(GLX_functions[i].Name, funcName) == 0)
+         return GLX_functions[i].Address;
+   }
+
+   return NULL;
+}
+
+
+/**
+ * Get the address of a named GL function.  This is the pre-GLX 1.4 name for
+ * \c glXGetProcAddress.
+ *
+ * \param procName  Name of a GL or GLX function.
+ * \returns         A pointer to the named function
+ *
+ * \sa glXGetProcAddress
+ */
+PUBLIC void (*glXGetProcAddressARB(const GLubyte * procName)) (void)
+{
+   typedef void (*gl_function) (void);
+   gl_function f;
+
+
+   /* Search the table of GLX and internal functions first.  If that
+    * fails and the supplied name could be a valid core GL name, try
+    * searching the core GL function table.  This check is done to prevent
+    * DRI based drivers from searching the core GL function table for
+    * internal API functions.
+    */
+
+   f = (gl_function) get_glx_proc_address((const char *) procName);
+   if ((f == NULL) && (procName[0] == 'g') && (procName[1] == 'l')
+       && (procName[2] != 'X')) {
+      f = (gl_function) _glapi_get_proc_address((const char *) procName);
+   }
+
+   return f;
+}
+
+/**
+ * Get the address of a named GL function.  This is the GLX 1.4 name for
+ * \c glXGetProcAddressARB.
+ *
+ * \param procName  Name of a GL or GLX function.
+ * \returns         A pointer to the named function
+ *
+ * \sa glXGetProcAddressARB
+ */
+PUBLIC void (*glXGetProcAddress(const GLubyte * procName)) (void)
+#if defined(__GNUC__) && !defined(GLX_ALIAS_UNSUPPORTED)
+   __attribute__ ((alias("glXGetProcAddressARB")));
+#else
+{
+   return glXGetProcAddressARB(procName);
+}
+#endif /* __GNUC__ */
+
+
+#ifdef GLX_DIRECT_RENDERING
+/**
+ * Get the unadjusted system time (UST).  Currently, the UST is measured in
+ * microseconds since Epoc.  The actual resolution of the UST may vary from
+ * system to system, and the units may vary from release to release.
+ * Drivers should not call this function directly.  They should instead use
+ * \c glXGetProcAddress to obtain a pointer to the function.
+ *
+ * \param ust Location to store the 64-bit UST
+ * \returns Zero on success or a negative errno value on failure.
+ *
+ * \sa glXGetProcAddress, PFNGLXGETUSTPROC
+ *
+ * \since Internal API version 20030317.
+ */
+_X_HIDDEN int
+__glXGetUST(int64_t * ust)
+{
+   struct timeval tv;
+
+   if (ust == NULL) {
+      return -EFAULT;
+   }
+
+   if (gettimeofday(&tv, NULL) == 0) {
+      ust[0] = (tv.tv_sec * 1000000) + tv.tv_usec;
+      return 0;
+   }
+   else {
+      return -errno;
+   }
+}
+#endif /* GLX_DIRECT_RENDERING */