patch to import Jon Smirl's work from Bitkeeper

1 files changed, 1975 insertions, 0 deletions

diff --git a/src/glx/mini/miniglx.c b/src/glx/mini/miniglx.c
new file mode 100644
index 00000000000..25c7b963624
--- /dev/null
+++ b/src/glx/mini/miniglx.c
@@ -0,0 +1,1975 @@
+/**
+ * \file miniglx.c
+ * \brief Mini GLX interface functions.
+ * \author Brian Paul
+ *
+ * The Mini GLX interface is a subset of the GLX interface, plus a
+ * minimal set of Xlib functions.
+ */
+
+/*
+ * Mesa 3-D graphics library
+ * Version:  5.0
+ *
+ * Copyright (C) 1999-2003  Brian Paul   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 and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * BRIAN PAUL 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.
+ */
+
+/* $Id: miniglx.c,v 1.1 2003/08/22 20:11:43 brianp Exp $ */
+
+/**
+ * \mainpage Mini GLX
+ *
+ * \section miniglxIntro Introduction
+ *
+ * The Mini GLX interface facilitates OpenGL rendering on embedded devices. The
+ * interface is a subset of the GLX interface, plus a minimal set of Xlib-like
+ * functions.
+ *
+ * Programs written to the Mini GLX specification should run unchanged
+ * on systems with the X Window System and the GLX extension (after
+ * recompilation). The intention is to allow flexibility for
+ * prototyping and testing.
+ *
+ * The files in the src/miniglx/ directory are compiled to build the
+ * libGL.so library.  This is the library which applications link with.
+ * libGL.so in turn, loads the hardware-specific device driver.
+ *
+ *
+ * \section miniglxDoxygen About Doxygen
+ *
+ * For a list of all files, select <b>File List</b>.  Choose a file from
+ * the list for a list of all functions in the file.
+ *
+ * For a list of all functions, types, constants, etc.
+ * select <b>File Members</b>.
+ *
+ *
+ * \section miniglxReferences References
+ *
+ * - <A HREF="file:../../docs/MiniGLX.html">Mini GLX Specification</A>,
+ *   Tungsten Graphics, Inc.
+ * - OpenGL Graphics with the X Window System, Silicon Graphics, Inc.,
+ *   ftp://ftp.sgi.com/opengl/doc/opengl1.2/glx1.3.ps
+ * - Xlib - C Language X Interface, X Consortium Standard, X Version 11,
+ *   Release 6.4, ftp://ftp.x.org/pub/R6.4/xc/doc/hardcopy/X11/xlib.PS.gz
+ * - XFree86 Man pages, The XFree86 Project, Inc.,
+ *   http://www.xfree86.org/current/manindex3.html
+ *   
+ */
+
+/**
+ * \page datatypes Notes on the XVisualInfo, Visual, and __GLXvisualConfig data types
+ * 
+ * -# X (unfortunately) has two (or three) data types which
+ *    describe visuals.  Ideally, there would just be one.
+ * -# We need the #__GLXvisualConfig type to augment #XVisualInfo and #Visual
+ *    because we need to describe the GLX-specific attributes of visuals.
+ * -# In this interface there is a one-to-one-to-one correspondence between
+ *    the three types and they're all interconnected.
+ * -# The #XVisualInfo type has a pointer to a #Visual.  The #Visual structure
+ *    (aka MiniGLXVisualRec) has a pointer to the #__GLXvisualConfig.  The
+ *    #Visual structure also has a pointer pointing back to the #XVisualInfo.
+ * -# The #XVisualInfo structure is the only one who's contents are public.
+ * -# The glXChooseVisual() and XGetVisualInfo() are the only functions that
+ *    return #XVisualInfo structures.  They can be freed with XFree(), though
+ *    there is a small memory leak.
+ */
+
+
+#include <assert.h>
+#include <errno.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <dlfcn.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <sys/ioctl.h>
+#include <sys/mman.h>
+#include <sys/types.h>
+#include <linux/kd.h>
+#include <linux/vt.h>
+
+#include "miniglxP.h"
+#include "dri.h"
+
+#include "glapi.h"
+#include "xf86drm.h"
+
+
+/**
+ * \brief Current GLX context.
+ *
+ * \sa glXGetCurrentContext().
+ */
+static GLXContext CurrentContext = NULL;
+
+
+
+static Display *SignalDisplay = 0;
+
+static void SwitchVT(int sig)
+{
+   fprintf(stderr, "SwitchVT %d dpy %p\n", sig, SignalDisplay);
+
+   if (SignalDisplay) {
+      SignalDisplay->vtSignalFlag = 1;
+      switch( sig )
+      {
+      case SIGUSR1:                                /* vt has been released */
+	 SignalDisplay->haveVT = 0;
+	 break;
+      case SIGUSR2:                                /* vt has been acquired */
+	 SignalDisplay->haveVT = 1;
+	 break;
+      }
+   }
+}
+
+/**********************************************************************/
+/** \name Framebuffer device functions                                */
+/**********************************************************************/
+/*@{*/
+
+/**
+ * \brief Do the first part of setting up the framebuffer device.
+ *
+ * \param dpy the display handle.
+ * \param use_vt use a VT for display or not
+ *
+ * \return GL_TRUE on success, or GL_FALSE on failure.
+ * 
+ * \sa This is called during XOpenDisplay().
+ *
+ * \internal
+ * Gets the VT number, opens the respective console TTY device. Saves its state
+ * to restore when exiting and goes into graphics mode.
+ *
+ * Opens the framebuffer device and make a copy of the original variable screen
+ * information and gets the fixed screen information.  Maps the framebuffer and
+ * MMIO region into the process address space.
+ */
+static GLboolean
+OpenFBDev( Display *dpy, int use_vt )
+{
+   char ttystr[1000];
+   int fd, vtnumber, ttyfd;
+
+   assert(dpy);
+
+   if (geteuid()) {
+      fprintf(stderr, "error: you need to be root\n");
+      return GL_FALSE;
+   }
+   
+   if (use_vt) {
+       
+       /* open /dev/tty0 and get the VT number */
+       if ((fd = open("/dev/tty0", O_WRONLY, 0)) < 0) {
+	   fprintf(stderr, "error opening /dev/tty0\n");
+	   return GL_FALSE;
+       }
+       if (ioctl(fd, VT_OPENQRY, &vtnumber) < 0 || vtnumber < 0) {
+	   fprintf(stderr, "error: couldn't get a free vt\n");
+	   return GL_FALSE;
+       }
+       
+       fprintf(stderr, "*** got vt nr: %d\n", vtnumber);
+       close(fd);
+       
+       /* open the console tty */
+       sprintf(ttystr, "/dev/tty%d", vtnumber);  /* /dev/tty1-64 */
+       dpy->ConsoleFD = open(ttystr, O_RDWR | O_NDELAY, 0);
+       if (dpy->ConsoleFD < 0) {
+	   fprintf(stderr, "error couldn't open console fd\n");
+	   return GL_FALSE;
+       }
+       
+       /* save current vt number */
+       {
+	   struct vt_stat vts;
+	   if (ioctl(dpy->ConsoleFD, VT_GETSTATE, &vts) == 0)
+	       dpy->OriginalVT = vts.v_active;
+       }
+       
+       /* disconnect from controlling tty */
+       ttyfd = open("/dev/tty", O_RDWR);
+       if (ttyfd >= 0) {
+	   ioctl(ttyfd, TIOCNOTTY, 0);
+	   close(ttyfd);
+       }
+       
+       /* some magic to restore the vt when we exit */
+       {
+	   struct vt_mode vt;
+	   struct sigaction sig_tty;
+	   
+	   /* Set-up tty signal handler to catch the signal we request below */
+	   SignalDisplay = dpy;
+	   memset( &sig_tty, 0, sizeof( sig_tty ) );
+	   sig_tty.sa_handler = SwitchVT;
+	   sigemptyset( &sig_tty.sa_mask );
+	   if( sigaction( SIGUSR1, &sig_tty, &dpy->OrigSigUsr1 ) ||
+	       sigaction( SIGUSR2, &sig_tty, &dpy->OrigSigUsr2 ) )
+	   {
+	       fprintf(stderr, "error: can't set up signal handler (%s)",
+		       strerror(errno) );
+	       return GL_FALSE;
+	   }
+	   
+	   
+	   
+	   vt.mode = VT_PROCESS;
+	   vt.waitv = 0;
+	   vt.relsig = SIGUSR1;
+	   vt.acqsig = SIGUSR2;
+	   if (ioctl(dpy->ConsoleFD, VT_SETMODE, &vt) < 0) {
+	       fprintf(stderr, "error: ioctl(VT_SETMODE) failed: %s\n",
+		       strerror(errno));
+	       return GL_FALSE;
+	   }
+	   
+	   
+	   if (ioctl(dpy->ConsoleFD, VT_ACTIVATE, vtnumber) != 0)
+	       printf("ioctl VT_ACTIVATE: %s\n", strerror(errno));
+	   if (ioctl(dpy->ConsoleFD, VT_WAITACTIVE, vtnumber) != 0)
+	       printf("ioctl VT_WAITACTIVE: %s\n", strerror(errno));
+	   
+	   if (ioctl(dpy->ConsoleFD, VT_GETMODE, &vt) < 0) {
+	       fprintf(stderr, "error: ioctl VT_GETMODE: %s\n", strerror(errno));
+	       return GL_FALSE;
+	   }
+	   
+	   
+	   
+       }
+       
+       /* go into graphics mode */
+       if (ioctl(dpy->ConsoleFD, KDSETMODE, KD_GRAPHICS) < 0) {
+	   fprintf(stderr, "error: ioctl(KDSETMODE, KD_GRAPHICS) failed: %s\n",
+		   strerror(errno));
+	   return GL_FALSE;
+       }
+   }
+
+   /* open the framebuffer device */
+   dpy->FrameBufferFD = open(dpy->fbdevDevice, O_RDWR);
+   if (dpy->FrameBufferFD < 0) {
+      fprintf(stderr, "Error opening /dev/fb0: %s\n", strerror(errno));
+      return GL_FALSE;
+   }
+
+  /* get the original variable screen info */
+   if (ioctl(dpy->FrameBufferFD, FBIOGET_VSCREENINFO, &dpy->OrigVarInfo)) {
+      fprintf(stderr, "error: ioctl(FBIOGET_VSCREENINFO) failed: %s\n",
+              strerror(errno));
+      return GL_FALSE;
+   }
+
+   /* make copy */
+   dpy->VarInfo = dpy->OrigVarInfo;  /* structure copy */
+
+   /* Turn off hw accels (otherwise mmap of mmio region will be
+    * refused)
+    */
+   dpy->VarInfo.accel_flags = 0; 
+   if (ioctl(dpy->FrameBufferFD, FBIOPUT_VSCREENINFO, &dpy->VarInfo)) {
+      fprintf(stderr, "error: ioctl(FBIOPUT_VSCREENINFO) failed: %s\n",
+	      strerror(errno));
+      return GL_FALSE;
+   }
+
+
+
+   /* Get the fixed screen info */
+   if (ioctl(dpy->FrameBufferFD, FBIOGET_FSCREENINFO, &dpy->FixedInfo)) {
+      fprintf(stderr, "error: ioctl(FBIOGET_FSCREENINFO) failed: %s\n",
+              strerror(errno));
+      return GL_FALSE;
+   }
+
+
+
+   /* mmap the framebuffer into our address space */
+   dpy->driverContext.FBStart = dpy->FixedInfo.smem_start;
+   dpy->driverContext.FBSize = dpy->FixedInfo.smem_len;
+   dpy->driverContext.shared.fbSize = dpy->FixedInfo.smem_len;
+   dpy->driverContext.FBAddress = (caddr_t) mmap(0, /* start */
+                                     dpy->driverContext.shared.fbSize, /* bytes */
+                                     PROT_READ | PROT_WRITE, /* prot */
+                                     MAP_SHARED, /* flags */
+                                     dpy->FrameBufferFD, /* fd */
+                                     0 /* offset */);
+   if (dpy->driverContext.FBAddress == (caddr_t) - 1) {
+      fprintf(stderr, "error: unable to mmap framebuffer: %s\n",
+              strerror(errno));
+      return GL_FALSE;
+   }
+	    
+   /* mmap the MMIO region into our address space */
+   dpy->driverContext.MMIOStart = dpy->FixedInfo.mmio_start;
+   dpy->driverContext.MMIOSize = dpy->FixedInfo.mmio_len;
+   dpy->driverContext.MMIOAddress = (caddr_t) mmap(0, /* start */
+                                     dpy->driverContext.MMIOSize, /* bytes */
+                                     PROT_READ | PROT_WRITE, /* prot */
+                                     MAP_SHARED, /* flags */
+                                     dpy->FrameBufferFD, /* fd */
+                                     dpy->FixedInfo.smem_len /* offset */);
+   if (dpy->driverContext.MMIOAddress == (caddr_t) - 1) {
+      fprintf(stderr, "error: unable to mmap mmio region: %s\n",
+              strerror(errno));
+      return GL_FALSE;
+   }
+
+   fprintf(stderr, "got MMIOAddress %p offset %d\n",
+           dpy->driverContext.MMIOAddress,
+	   dpy->FixedInfo.smem_len);
+
+   return GL_TRUE;
+}
+
+
+
+
+/**
+ * \brief Setup up the desired framebuffer device mode.  
+ *
+ * \param dpy the display handle.
+ * 
+ * \return GL_TRUE on success, or GL_FALSE on failure.
+ * 
+ * \sa This is called during __miniglx_StartServer().
+ *
+ * \internal
+ *
+ * Bumps the size of the window the the next supported mode. Sets the
+ * variable screen information according to the desired mode and asks
+ * the driver to validate the mode. Certifies that a DirectColor or
+ * TrueColor visual is used from the updated fixed screen information.
+ * In the case of DirectColor visuals, sets up an 'identity' colormap to
+ * mimic a TrueColor visual.
+ *
+ * Calls the driver hooks 'ValidateMode' and 'PostValidateMode' to
+ * allow the driver to make modifications to the chosen mode according
+ * to hardware constraints, or to save and restore videocard registers
+ * that may be clobbered by the fbdev driver.
+ *
+ * \todo Timings are hard-coded in the source for a set of supported modes.
+ */
+static GLboolean
+SetupFBDev( Display *dpy )
+{
+   int width, height;
+
+   assert(dpy);
+
+   width = dpy->driverContext.shared.virtualWidth;
+   height = dpy->driverContext.shared.virtualHeight;
+   
+   /* Bump size up to next supported mode.
+    */
+   if (width <= 800 && height <= 600) {
+      width = 800; height = 600; 
+   }  
+   else if (width <= 1024 && height <= 768) { 
+      width = 1024; height = 768; 
+   } 
+   else if (width <= 768 && height <= 1024) {
+      width = 768; height = 1024; 
+   }  
+   else if (width <= 1280 && height <= 1024) { 
+      width = 1280; height = 1024; 
+   } 
+
+
+   dpy->driverContext.shared.virtualHeight = height;
+   dpy->driverContext.shared.virtualWidth = width;
+   dpy->driverContext.shared.fbStride = width * (dpy->driverContext.bpp / 8);
+   
+   /* set the depth, resolution, etc */
+   dpy->VarInfo = dpy->OrigVarInfo;
+   dpy->VarInfo.bits_per_pixel = dpy->driverContext.bpp;
+   dpy->VarInfo.xres_virtual = dpy->driverContext.shared.virtualWidth;
+   dpy->VarInfo.yres_virtual = dpy->driverContext.shared.virtualHeight;
+   dpy->VarInfo.xres = width;
+   dpy->VarInfo.yres = height;
+   dpy->VarInfo.xoffset = 0;
+   dpy->VarInfo.yoffset = 0;
+   dpy->VarInfo.nonstd = 0;
+   dpy->VarInfo.vmode &= ~FB_VMODE_YWRAP; /* turn off scrolling */
+
+   if (dpy->VarInfo.bits_per_pixel == 32) {
+      dpy->VarInfo.red.offset = 16;
+      dpy->VarInfo.green.offset = 8;
+      dpy->VarInfo.blue.offset = 0;
+      dpy->VarInfo.transp.offset = 24;
+      dpy->VarInfo.red.length = 8;
+      dpy->VarInfo.green.length = 8;
+      dpy->VarInfo.blue.length = 8;
+      dpy->VarInfo.transp.length = 8;
+   }
+   else if (dpy->VarInfo.bits_per_pixel == 16) {
+      dpy->VarInfo.red.offset = 11;
+      dpy->VarInfo.green.offset = 5;
+      dpy->VarInfo.blue.offset = 0;
+      dpy->VarInfo.red.length = 5;
+      dpy->VarInfo.green.length = 6;
+      dpy->VarInfo.blue.length = 5;
+      dpy->VarInfo.transp.offset = 0;
+      dpy->VarInfo.transp.length = 0;
+   }
+   else {
+      fprintf(stderr, "Only 32bpp and 16bpp modes supported at the moment\n");
+      return 0;
+   }
+
+   if (!dpy->driver->validateMode( &dpy->driverContext )) {
+      fprintf(stderr, "Driver validateMode() failed\n");
+      return 0;
+   }
+
+   if (dpy->VarInfo.xres == 1280 && 
+       dpy->VarInfo.yres == 1024) {
+      /* timing values taken from /etc/fb.modes (1280x1024 @ 75Hz) */
+      dpy->VarInfo.pixclock = 7408;
+      dpy->VarInfo.left_margin = 248;
+      dpy->VarInfo.right_margin = 16;
+      dpy->VarInfo.upper_margin = 38;
+      dpy->VarInfo.lower_margin = 1;
+      dpy->VarInfo.hsync_len = 144;
+      dpy->VarInfo.vsync_len = 3;
+   }
+   else if (dpy->VarInfo.xres == 1024 && 
+	    dpy->VarInfo.yres == 768) {
+      /* timing values taken from /etc/fb.modes (1024x768 @ 75Hz) */
+      dpy->VarInfo.pixclock = 12699;
+      dpy->VarInfo.left_margin = 176;
+      dpy->VarInfo.right_margin = 16;
+      dpy->VarInfo.upper_margin = 28;
+      dpy->VarInfo.lower_margin = 1;
+      dpy->VarInfo.hsync_len = 96;
+      dpy->VarInfo.vsync_len = 3;
+   }
+   else if (dpy->VarInfo.xres == 800 &&
+	    dpy->VarInfo.yres == 600) {
+      /* timing values taken from /etc/fb.modes (800x600 @ 75Hz) */
+      dpy->VarInfo.pixclock = 20203;
+      dpy->VarInfo.left_margin = 160;
+      dpy->VarInfo.right_margin = 16;
+      dpy->VarInfo.upper_margin = 21;
+      dpy->VarInfo.lower_margin = 1;
+      dpy->VarInfo.hsync_len = 80;
+      dpy->VarInfo.vsync_len = 3;
+   }
+   else if (dpy->VarInfo.xres == 768 &&
+	    dpy->VarInfo.yres == 1024) {
+      /* timing values for 768x1024 @ 75Hz */
+      dpy->VarInfo.pixclock = 11993;
+      dpy->VarInfo.left_margin = 136;
+      dpy->VarInfo.right_margin = 32;
+      dpy->VarInfo.upper_margin = 41;
+      dpy->VarInfo.lower_margin = 1;
+      dpy->VarInfo.hsync_len = 80;
+      dpy->VarInfo.vsync_len = 3;
+   }
+   else {
+      /* XXX need timings for other screen sizes */
+      fprintf(stderr, "XXXX screen size %d x %d not supported at this time!\n",
+	      dpy->VarInfo.xres, dpy->VarInfo.yres);
+      return GL_FALSE;
+   }
+
+   fprintf(stderr, "[miniglx] Setting mode: visible %dx%d virtual %dx%dx%d\n",
+	   dpy->VarInfo.xres, dpy->VarInfo.yres,
+	   dpy->VarInfo.xres_virtual, dpy->VarInfo.yres_virtual,
+	   dpy->VarInfo.bits_per_pixel);
+
+   /* set variable screen info */
+   if (ioctl(dpy->FrameBufferFD, FBIOPUT_VSCREENINFO, &dpy->VarInfo)) {
+      fprintf(stderr, "error: ioctl(FBIOPUT_VSCREENINFO) failed: %s\n",
+	      strerror(errno));
+      return GL_FALSE;
+   }
+
+   /* get the variable screen info, in case it has been modified */
+   if (ioctl(dpy->FrameBufferFD, FBIOGET_VSCREENINFO, &dpy->VarInfo)) {
+      fprintf(stderr, "error: ioctl(FBIOGET_VSCREENINFO) failed: %s\n",
+              strerror(errno));
+      return GL_FALSE;
+   }
+
+
+   fprintf(stderr, "[miniglx] Readback mode: visible %dx%d virtual %dx%dx%d\n",
+	   dpy->VarInfo.xres, dpy->VarInfo.yres,
+	   dpy->VarInfo.xres_virtual, dpy->VarInfo.yres_virtual,
+	   dpy->VarInfo.bits_per_pixel);
+
+   /* Get the fixed screen info */
+   if (ioctl(dpy->FrameBufferFD, FBIOGET_FSCREENINFO, &dpy->FixedInfo)) {
+      fprintf(stderr, "error: ioctl(FBIOGET_FSCREENINFO) failed: %s\n",
+              strerror(errno));
+      return GL_FALSE;
+   }
+
+   if (dpy->FixedInfo.visual != FB_VISUAL_TRUECOLOR &&
+       dpy->FixedInfo.visual != FB_VISUAL_DIRECTCOLOR) {
+      fprintf(stderr, "non-TRUECOLOR visuals not supported.\n");
+      return GL_FALSE;
+   }
+
+   if (dpy->FixedInfo.visual == FB_VISUAL_DIRECTCOLOR) {
+      struct fb_cmap cmap;
+      unsigned short red[256], green[256], blue[256];
+      int rcols = 1 << dpy->VarInfo.red.length;
+      int gcols = 1 << dpy->VarInfo.green.length;
+      int bcols = 1 << dpy->VarInfo.blue.length;
+      int i;
+
+      cmap.start = 0;      
+      cmap.len = gcols;
+      cmap.red   = red;
+      cmap.green = green;
+      cmap.blue  = blue;
+      cmap.transp = NULL;
+
+      for (i = 0; i < rcols ; i++) 
+         red[i] = (65536/(rcols-1)) * i;
+
+      for (i = 0; i < gcols ; i++) 
+         green[i] = (65536/(gcols-1)) * i;
+
+      for (i = 0; i < bcols ; i++) 
+         blue[i] = (65536/(bcols-1)) * i;
+      
+      if (ioctl(dpy->FrameBufferFD, FBIOPUTCMAP, (void *) &cmap) < 0) {
+         fprintf(stderr, "ioctl(FBIOPUTCMAP) failed [%d]\n", i);
+	 exit(1);
+      }
+   }
+
+   /* May need to restore regs fbdev has clobbered:
+    */
+   if (!dpy->driver->postValidateMode( &dpy->driverContext )) {
+      fprintf(stderr, "Driver postValidateMode() failed\n");
+      return 0;
+   }
+
+   return GL_TRUE;
+}
+
+
+/**
+ * \brief Restore the framebuffer device to state it was in before we started
+ *
+ * Undoes the work done by SetupFBDev().
+ * 
+ * \param dpy the display handle.
+ *
+ * \return GL_TRUE on success, or GL_FALSE on failure.
+ * 
+ * \sa Called from XDestroyWindow().
+ *
+ * \internal
+ * Restores the original variable screen info.
+ */
+static GLboolean
+RestoreFBDev( Display *dpy )
+{
+   /* restore original variable screen info */
+   if (ioctl(dpy->FrameBufferFD, FBIOPUT_VSCREENINFO, &dpy->OrigVarInfo)) {
+      fprintf(stderr, "ioctl(FBIOPUT_VSCREENINFO failed): %s\n",
+              strerror(errno));
+      return GL_FALSE;
+   }
+   dpy->VarInfo = dpy->OrigVarInfo;
+
+   return GL_TRUE;
+}
+
+
+/**
+ * \brief Close the framebuffer device.  
+ *
+ * \param dpy the display handle.
+ * 
+ * \sa Called from XCloseDisplay().
+ *
+ * \internal
+ * Unmaps the framebuffer and MMIO region.  Restores the text mode and the
+ * original virtual terminal. Closes the console and framebuffer devices.
+ */
+static void
+CloseFBDev( Display *dpy )
+{
+   struct vt_mode VT;
+
+   munmap(dpy->driverContext.FBAddress, dpy->driverContext.FBSize);
+   munmap(dpy->driverContext.MMIOAddress, dpy->driverContext.MMIOSize);
+
+   if (dpy->ConsoleFD) {
+       /* restore text mode */
+       ioctl(dpy->ConsoleFD, KDSETMODE, KD_TEXT);
+       
+       /* set vt */
+       if (ioctl(dpy->ConsoleFD, VT_GETMODE, &VT) != -1) {
+	   VT.mode = VT_AUTO;
+	   ioctl(dpy->ConsoleFD, VT_SETMODE, &VT);
+       }
+       
+       /* restore original vt */
+       if (dpy->OriginalVT >= 0) {
+	   ioctl(dpy->ConsoleFD, VT_ACTIVATE, dpy->OriginalVT);
+	   dpy->OriginalVT = -1;
+       }
+       
+       close(dpy->ConsoleFD);
+   }
+   close(dpy->FrameBufferFD);
+}
+
+/*@}*/
+
+
+/**********************************************************************/
+/** \name Misc functions needed for DRI drivers                       */
+/**********************************************************************/
+/*@{*/
+
+/**
+ * \brief Find the DRI screen dependent methods associated with the display.
+ *
+ * \param dpy a display handle, as returned by XOpenDisplay().
+ * \param scrn the screen number. Not referenced.
+ * 
+ * \returns a pointer to a __DRIscreenRec structure.
+ * 
+ * \internal
+ * Returns the MiniGLXDisplayRec::driScreen attribute.
+ */
+__DRIscreen *
+__glXFindDRIScreen(Display *dpy, int scrn)
+{
+   (void) scrn;
+   return dpy->driScreen;
+}
+
+/**
+ * \brief Validate a drawable.
+ *
+ * \param dpy a display handle, as returned by XOpenDisplay().
+ * \param draw drawable to validate.
+ * 
+ * \internal
+ * Since Mini GLX only supports one window, compares the specified drawable with
+ * the MiniGLXDisplayRec::TheWindow attribute.
+ */
+Bool
+__glXWindowExists(Display *dpy, GLXDrawable draw)
+{
+   if (dpy->TheWindow == draw)
+      return True;
+   else
+      return False;
+}
+
+/**
+ * \brief Get current thread ID.
+ *
+ * \return thread ID.
+ *
+ * \internal
+ * Always returns 0. 
+ */
+/*unsigned long
+_glthread_GetID(void)
+{
+   return 0;
+}*/
+
+/*@}*/
+
+
+/**
+ * \brief Scan Linux /prog/bus/pci/devices file to determine hardware
+ * chipset based on supplied bus ID.
+ * 
+ * \return probed chipset (non-zero) on success, zero otherwise.
+ * 
+ * \internal 
+ */
+static int get_chipset_from_busid( Display *dpy )
+{
+   char buf[0x200];
+   FILE *file;
+   const char *fname = "/proc/bus/pci/devices";
+   int retval = 0;
+
+   if (!(file = fopen(fname,"r"))) {
+      fprintf(stderr, "couldn't open %s: %s\n", fname, strerror(errno));
+      return 0;
+   }
+
+   while (fgets(buf, sizeof(buf)-1, file)) {
+      unsigned int nr, bus, dev, fn, vendor, device, encode;
+      nr = sscanf(buf, "%04x\t%04x%04x", &encode, 
+		  &vendor, &device);
+      
+      bus = encode >> 16;
+      dev = (encode & 0xFF) >> 3;
+      fn = encode & 0x7;
+
+      if (nr != 3)
+	 break;
+
+      if (bus == dpy->driverContext.pciBus &&
+          dev == dpy->driverContext.pciDevice &&
+          fn  == dpy->driverContext.pciFunc) {
+	 retval = device;
+	 break;
+      }
+   }
+
+   fclose(file);
+
+   if (retval)
+      fprintf(stderr, "[miniglx] probed chipset 0x%x\n", retval);
+   else
+      fprintf(stderr, "[miniglx] failed to probe chipset\n");
+
+   return retval;
+}
+
+
+/**
+ * \brief Read settings from a configuration file.
+ * 
+ * The configuration file is usually "/etc/miniglx.conf", but can be overridden
+ * with the MINIGLX_CONF environment variable. 
+ *
+ * The format consists in \code option = value \endcode lines. The option names 
+ * corresponds to the fields in MiniGLXDisplayRec.
+ * 
+ * \param dpy the display handle as.
+ *
+ * \return non-zero on success, zero otherwise.
+ * 
+ * \internal 
+ * Sets some defaults. Opens and parses the the Mini GLX configuration file and
+ * fills in the MiniGLXDisplayRec field that corresponds for each option.
+ */
+static int __read_config_file( Display *dpy )
+{
+   FILE *file;
+   const char *fname;
+
+   /* Fallback/defaults
+    */
+   dpy->fbdevDevice = "/dev/fb0";
+   dpy->clientDriverName = "fb_dri.so";
+   dpy->driverContext.pciBus = 0;
+   dpy->driverContext.pciDevice = 0;
+   dpy->driverContext.pciFunc = 0;
+   dpy->driverContext.chipset = 0;   
+   dpy->driverContext.pciBusID = 0;
+   dpy->driverContext.shared.virtualWidth = 1280;
+   dpy->driverContext.shared.virtualHeight = 1024;
+   dpy->driverContext.bpp = 32;
+   dpy->driverContext.cpp = 4;
+   dpy->rotateMode = 0;
+
+   fname = getenv("MINIGLX_CONF");
+   if (!fname) fname = "/etc/miniglx.conf";
+
+   file = fopen(fname, "r");
+   if (!file) {
+      fprintf(stderr, "couldn't open config file %s: %s\n", fname, strerror(errno));
+      return 0;
+   }
+
+
+   while (!feof(file)) {
+      char buf[81], *opt = buf, *val, *tmp1, *tmp2;
+      fgets(buf, sizeof(buf), file); 
+
+      /* Parse 'opt = val' -- must be easier ways to do this.
+       */
+      while (isspace(*opt)) opt++;
+      val = opt;
+      if (*val == '#') continue; /* comment */
+      while (!isspace(*val) && *val != '=' && *val) val++;
+      tmp1 = val;
+      while (isspace(*val)) val++;
+      if (*val != '=') continue;
+      *tmp1 = 0; 
+      val++;
+      while (isspace(*val)) val++;
+      tmp2 = val;
+      while (!isspace(*tmp2) && *tmp2 != '\n' && *tmp2) tmp2++;
+      *tmp2 = 0;
+
+
+      if (strcmp(opt, "fbdevDevice") == 0) 
+	 dpy->fbdevDevice = strdup(val);
+      else if (strcmp(opt, "clientDriverName") == 0)
+	 dpy->clientDriverName = strdup(val);
+      else if (strcmp(opt, "rotateMode") == 0)
+	 dpy->rotateMode = atoi(val) ? 1 : 0;
+      else if (strcmp(opt, "pciBusID") == 0) {
+	 if (sscanf(val, "PCI:%d:%d:%d",
+		    &dpy->driverContext.pciBus,
+                    &dpy->driverContext.pciDevice,
+                    &dpy->driverContext.pciFunc) != 3) {
+	    fprintf(stderr, "malformed bus id: %s\n", val);
+	    continue;
+	 }
+   	 dpy->driverContext.pciBusID = strdup(val);
+      }
+      else if (strcmp(opt, "chipset") == 0) {
+	 if (sscanf(val, "0x%x", &dpy->driverContext.chipset) != 1)
+	    fprintf(stderr, "malformed chipset: %s\n", opt);
+      }
+      else if (strcmp(opt, "virtualWidth") == 0) {
+	 if (sscanf(val, "%d", &dpy->driverContext.shared.virtualWidth) != 1)
+	    fprintf(stderr, "malformed virtualWidth: %s\n", opt);
+      }
+      else if (strcmp(opt, "virtualHeight") == 0) {
+	 if (sscanf(val, "%d", &dpy->driverContext.shared.virtualHeight) != 1)
+	    fprintf(stderr, "malformed virutalHeight: %s\n", opt);
+      }
+      else if (strcmp(opt, "bpp") == 0) {
+	 if (sscanf(val, "%d", &dpy->driverContext.bpp) != 1)
+	    fprintf(stderr, "malformed bpp: %s\n", opt);
+	 dpy->driverContext.cpp = dpy->driverContext.bpp / 8;
+      }
+   }
+
+   fclose(file);
+
+   if (dpy->driverContext.chipset == 0 && dpy->driverContext.pciBusID != 0) 
+      dpy->driverContext.chipset = get_chipset_from_busid( dpy );
+
+   return 1;
+}
+
+static int InitDriver( Display *dpy )
+{
+   /*
+    * Begin DRI setup.
+    * We're kind of combining the per-display and per-screen information
+    * which was kept separate in XFree86/DRI's libGL.
+    */
+   dpy->dlHandle = dlopen(dpy->clientDriverName, RTLD_NOW | RTLD_GLOBAL);
+   if (!dpy->dlHandle) {
+      fprintf(stderr, "Unable to open %s: %s\n", dpy->clientDriverName,
+	      dlerror());
+      return GL_FALSE;
+   }
+
+   /* Pull in Mini GLX specific hooks:
+    */
+   dpy->driver = (struct DRIDriverRec *) dlsym(dpy->dlHandle,
+                                               "__driDriver");
+   if (!dpy->driver) {
+      fprintf(stderr, "Couldn't find __driDriver in %s\n",
+              dpy->clientDriverName);
+      dlclose(dpy->dlHandle);
+      return GL_FALSE;
+   }
+
+   /* Pull in standard DRI client-side driver hooks:
+    */
+   dpy->createScreen = (driCreateScreenFunc*) dlsym(dpy->dlHandle,
+                                                "__driCreateScreen");
+   if (!dpy->createScreen) {
+      fprintf(stderr, "Couldn't find __driCreateScreen in %s\n",
+              dpy->clientDriverName);
+      dlclose(dpy->dlHandle);
+      return GL_FALSE;
+   }
+
+   return GL_TRUE;
+}
+
+
+/**********************************************************************/
+/** \name Public API functions (Xlib and GLX)                         */
+/**********************************************************************/
+/*@{*/
+
+
+/**
+ * \brief Initialize the graphics system.
+ * 
+ * \param display_name currently ignored. It is recommended to pass it as NULL.
+ * \return a pointer to a #Display if the function is able to initialize
+ * the graphics system, NULL otherwise.
+ * 
+ * Allocates a MiniGLXDisplayRec structure and fills in with information from a
+ * configuration file. 
+ *
+ * Calls OpenFBDev() to open the framebuffer device and calls
+ * DRIDriverRec::initFBDev to do the client-side initialization on it.
+ *
+ * Loads the DRI driver and pulls in Mini GLX specific hooks into a
+ * DRIDriverRec structure, and the standard DRI \e __driCreateScreen hook.
+ * Asks the driver for a list of supported visuals.  Performs the per-screen
+ * client-side initialization.  Also setups the callbacks in the screen private
+ * information.
+ *
+ * Does the framebuffer device setup. Calls __miniglx_open_connections() to
+ * serve clients.
+ */
+Display *
+__miniglx_StartServer( const char *display_name )
+{
+   Display *dpy;
+   int use_vt = 0;
+
+   dpy = (Display *)calloc(1, sizeof(Display));
+   if (!dpy)
+      return NULL;
+
+   dpy->IsClient = False;
+
+   if (!__read_config_file( dpy )) {
+      fprintf(stderr, "Couldn't get configuration details\n");
+      free(dpy);
+      return NULL;
+   }
+
+   /* Open the fbdev device
+    */
+   if (!OpenFBDev(dpy, use_vt)) {
+      fprintf(stderr, "OpenFBDev failed\n");
+      free(dpy);
+      return NULL;
+   }
+
+   if (!InitDriver(dpy)) {
+      fprintf(stderr, "InitDriver failed\n");
+      free(dpy);
+      return NULL;
+   }
+
+   /* Ask the driver for a list of supported configs:
+   */
+   dpy->driver->initContextModes( &dpy->driverContext, &dpy->numModes, &dpy->modes );
+
+   /* Perform the initialization normally done in the X server 
+    */
+   if (!dpy->driver->initFBDev( &dpy->driverContext )) {
+      fprintf(stderr, "%s: __driInitFBDev failed\n", __FUNCTION__);
+      dlclose(dpy->dlHandle);
+      return GL_FALSE;
+   }
+
+   /* do fbdev setup
+    */
+   if (!SetupFBDev(dpy)) {
+      fprintf(stderr, "SetupFBDev failed\n");
+      free(dpy);
+      return NULL;
+   }
+
+   /* unlock here if not using VT -- JDS */
+   if (!use_vt) {
+       if (dpy->driver->restoreHardware)
+	   dpy->driver->restoreHardware( &dpy->driverContext ); 
+       DRM_UNLOCK( dpy->driverContext.drmFD,
+		   dpy->driverContext.pSAREA,
+		   dpy->driverContext.serverContext );
+       dpy->hwActive = 1;
+   }
+
+   /* Ready for clients:
+    */
+   if (!__miniglx_open_connections(dpy)) {
+      free(dpy);
+      return NULL;
+   }
+      
+   return dpy;
+}
+
+
+/**
+ * \brief Initialize the graphics system.
+ * 
+ * \param display_name currently ignored. It is recommended to pass it as NULL.
+ * \return a pointer to a #Display if the function is able to initialize
+ * the graphics system, NULL otherwise.
+ * 
+ * Allocates a MiniGLXDisplayRec structure and fills in with information from a
+ * configuration file. 
+ *
+ * Calls __miniglx_open_connections() to connect to the server.
+ * 
+ * Loads the DRI driver and pulls in Mini GLX specific hooks into a
+ * DRIDriverRec structure, and the standard DRI \e __driCreateScreen hook.
+ * Asks the driver for a list of supported visuals.  Performs the per-screen
+ * client-side initialization.  Also setups the callbacks in the screen private
+ * information.
+ *
+ * \todo
+ *   - read config file
+ *      - what about virtualWidth, etc?
+ *   - determine dpy->driverClientMsgSize,
+ *   - allocate dpy->driverClientMsg
+ */
+Display *
+XOpenDisplay( const char *display_name )
+{
+   Display *dpy;
+
+   dpy = (Display *)calloc(1, sizeof(Display));
+   if (!dpy)
+      return NULL;
+
+   dpy->IsClient = True;
+
+   /* read config file 
+    */
+   if (!__read_config_file( dpy )) {
+      fprintf(stderr, "Couldn't get configuration details\n");
+      free(dpy);
+      return NULL;
+   }
+
+   /* Connect to the server and receive driverClientMsg
+    */
+   if (!__miniglx_open_connections(dpy)) {
+      free(dpy);
+      return NULL;
+   }
+
+   /* dlopen the driver .so file
+    */
+   if (!InitDriver(dpy)) {
+      fprintf(stderr, "InitDriver failed\n");
+      free(dpy);
+      return NULL;
+   }
+
+   /* Ask the driver for a list of supported configs:
+   */
+   dpy->driver->initContextModes( &dpy->driverContext, &dpy->numModes, &dpy->modes );
+   
+   /* Perform the client-side initialization.  
+    *
+    * Clearly there is a limit of one on the number of windows in
+    * existence at any time.
+    *
+    * Need to shut down DRM and free DRI data in XDestroyWindow(), too.
+    */
+   dpy->driScreen = (*dpy->createScreen)(dpy->driver,
+					 &dpy->driverContext);
+   if (!dpy->driScreen) {
+      fprintf(stderr, "%s: __driCreateScreen failed\n", __FUNCTION__);
+      dlclose(dpy->dlHandle);
+      free(dpy);
+      return NULL;
+   }
+   
+   /* Anything more to do?
+    */
+   return dpy;
+}
+
+
+/**
+ * \brief Release display resources.
+ * 
+ * When the application is about to exit, the resources associated with the
+ * graphics system can be released by calling this function.
+ * 
+ * \param dpy display handle. It becomes invalid at this point.
+ * 
+ * Destroys the window if any, and destroys the per-screen
+ * driver private information.
+ * Calls __miniglx_close_connections().
+ * 
+ * If a server, puts the the framebuffer back into the initial state.
+ *
+ * Finally frees the display structure.
+ */
+void
+XCloseDisplay( Display *dpy )
+{
+   glXMakeCurrent( dpy, NULL, NULL);
+
+   if (dpy->NumWindows) 
+      XDestroyWindow( dpy, dpy->TheWindow );
+
+   /* As this is done in XOpenDisplay, need to undo it here:
+    */
+   (*dpy->driScreen->destroyScreen)(dpy->driScreen);
+
+   __miniglx_close_connections( dpy );
+
+   if (!dpy->IsClient) {
+      /* put framebuffer back to initial state 
+       */
+      (*dpy->driver->haltFBDev)( &dpy->driverContext );
+      RestoreFBDev(dpy);
+      CloseFBDev(dpy);
+   }
+
+   dlclose(dpy->dlHandle);
+   free(dpy);
+}
+
+
+/**
+ * \brief Window creation.
+ *
+ * \param display a display handle, as returned by XOpenDisplay().
+ * \param parent the parent window for the new window. For Mini GLX this should
+ * be 
+ * \code RootWindow(display, 0) \endcode
+ * \param x the window abscissa. For Mini GLX, it should be zero.
+ * \param y the window ordinate. For Mini GLX, it should be zero.
+ * \param width the window width. For Mini GLX, this specifies the desired
+ * screen width such as 1024 or 1280. 
+ * \param height the window height. For Mini GLX, this specifies the desired
+ * screen height such as 768 or 1024.
+ * \param border_width the border width. For Mini GLX, it should be zero.
+ * \param depth the window pixel depth. For Mini GLX, this should be the depth
+ * found in the #XVisualInfo object returned by glXChooseVisual() 
+ * \param class the window class. For Mini GLX this value should be
+ * #InputOutput.
+ * \param visual the visual type. It should be the visual field of the
+ * #XVisualInfo object returned by glXChooseVisual().
+ * \param valuemask which fields of the XSetWindowAttributes() are to be used.
+ * For Mini GLX this is typically the bitmask 
+ * \code CWBackPixel | CWBorderPixel | CWColormap \endcode
+ * \param attributes initial window attributes. The
+ * XSetWindowAttributes::background_pixel, XSetWindowAttributes::border_pixel
+ * and XSetWindowAttributes::colormap fields should be set.
+ *
+ * \return a window handle if it succeeds or zero if it fails.
+ * 
+ * \note For Mini GLX, windows are full-screen; they cover the entire frame
+ * buffer.  Also, Mini GLX imposes a limit of one window. A second window
+ * cannot be created until the first one is destroyed.
+ *
+ * This function creates and initializes a ::MiniGLXWindowRec structure after
+ * ensuring that there is no other window created.  Performs the per-drawable
+ * client-side initialization calling the __DRIscreenRec::createDrawable
+ * method.
+ * 
+ */
+Window
+XCreateWindow( Display *dpy, Window parent, int x, int y,
+               unsigned int width, unsigned int height,
+               unsigned int border_width, int depth, unsigned int class,
+               Visual *visual, unsigned long valuemask,
+               XSetWindowAttributes *attributes )
+{
+   Window win;
+
+   /* ignored */
+   (void) x;
+   (void) y;
+   (void) border_width;
+   (void) depth;
+   (void) class;
+   (void) valuemask;
+   (void) attributes;
+
+   if (!dpy->IsClient) {
+      fprintf(stderr, "Server process may not create windows (currently)\n");
+      return NULL;
+   }
+
+   if (dpy->NumWindows > 0)
+      return NULL;  /* only allow one window */
+
+   assert(dpy->TheWindow == NULL);
+
+   win = malloc(sizeof(struct MiniGLXWindowRec));
+   if (!win)
+      return NULL;
+
+   /* In rotated mode, translate incoming x,y,width,height into
+    * 'normal' coordinates.
+    */
+   if (dpy->rotateMode) {
+      int tmp;
+      tmp = width; width = height; height = tmp;
+      tmp = x; x = y; y = tmp;
+   }
+
+   /* init other per-window fields */
+   win->x = 0;
+   win->y = 0;
+   win->w = width;
+   win->h = height;
+   win->visual = visual;  /* ptr assignment */
+
+   win->bytesPerPixel = dpy->driverContext.cpp;
+   win->rowStride = dpy->driverContext.shared.virtualWidth * win->bytesPerPixel;
+   win->size = win->rowStride * height; 
+   win->frontStart = dpy->driverContext.FBAddress;
+   win->frontBottom = (GLubyte *) win->frontStart + (height-1) * win->rowStride;
+
+   /* This is incorrect: the hardware driver could put the backbuffer
+    * just about anywhere.  These fields, including the above are
+    * hardware dependent & don't really belong here.
+    */
+   if (visual->mode->doubleBufferMode) {
+      win->backStart = (GLubyte *) win->frontStart +
+	 win->rowStride * dpy->driverContext.shared.virtualHeight;
+      win->backBottom = (GLubyte *) win->backStart
+	 + (height - 1) * win->rowStride;
+      win->curBottom = win->backBottom;
+   }
+   else {
+      /* single buffered */
+      win->backStart = NULL;
+      win->backBottom = NULL;
+      win->curBottom = win->frontBottom;
+   }
+
+   win->driDrawable = dpy->driScreen->createDrawable(dpy->driScreen, 
+						     width, height, 
+						     dpy->clientID, visual->mode);
+
+   if (!win->driDrawable) {
+      fprintf(stderr, "%s: dri.createDrawable failed\n", __FUNCTION__);
+      free(win);
+      return NULL;
+   }
+
+   dpy->NumWindows++;
+   dpy->TheWindow = win;
+
+   return win; 
+}
+
+
+/**
+ * \brief Destroy window.
+ *
+ * \param display display handle.
+ * \param w window handle.
+ *
+ * This function calls XUnmapWindow() and frees window \p w.
+ * 
+ * In case of destroying the current buffer first unbinds the GLX context
+ * by calling glXMakeCurrent() with no drawable.
+ */
+void
+XDestroyWindow( Display *display, Window win )
+{
+   if (display && display->IsClient && win) {
+      /* check if destroying the current buffer */
+      Window curDraw = glXGetCurrentDrawable();
+      if (win == curDraw) {
+         glXMakeCurrent( display, NULL, NULL);
+      }
+
+      XUnmapWindow( display, win );
+
+      /* Destroy the drawable. */
+      (*win->driDrawable->destroyDrawable)(win->driDrawable);
+      free(win);
+      
+      /* unlink window from display */
+      display->NumWindows--;
+      assert(display->NumWindows == 0);
+      display->TheWindow = NULL;
+   }
+}
+
+
+
+
+/**
+ * \brief Create color map structure.
+ *
+ * \param dpy the display handle as returned by XOpenDisplay().
+ * \param w the window on whose screen you want to create a color map. This
+ * parameter is ignored by Mini GLX but should be the value returned by the
+ * \code RootWindow(display, 0) \endcode macro.
+ * \param visual a visual type supported on the screen. This parameter is
+ * ignored by Mini GLX but should be the XVisualInfo::visual returned by
+ * glXChooseVisual().
+ * \param alloc the color map entries to be allocated. This parameter is ignored
+ * by Mini GLX but should be set to #AllocNone.
+ *
+ * \return the color map.
+ * 
+ * This function is only provided to ease porting.  Practically a no-op -
+ * returns a pointer to a dynamically allocated chunk of memory (one byte).
+ */
+Colormap
+XCreateColormap( Display *dpy, Window w, Visual *visual, int alloc )
+{
+   (void) dpy;
+   (void) w;
+   (void) visual;
+   (void) alloc;
+   return (Colormap) malloc(1);
+}
+
+
+/**
+ * \brief Destroy color map structure.
+ *
+ * \param display The display handle as returned by XOpenDisplay().
+ * \param colormap the color map to destroy.
+ *
+ * This function is only provided to ease porting.  Practically a no-op. 
+ *
+ * Frees the memory pointed by \p colormap.
+ */
+void
+XFreeColormap( Display *display, Colormap colormap )
+{
+   (void) display;
+   (void) colormap;
+   free(colormap);
+}
+
+
+/**
+ * \brief Free client data.
+ *
+ * \param data the data that is to be freed.
+ *
+ * Frees the memory pointed by \p data.
+ */
+void
+XFree( void *data )
+{
+   free(data);
+}
+
+
+/**
+ * \brief Query available visuals.
+ *
+ * \param dpy the display handle, as returned by XOpenDisplay().
+ * \param vinfo_mask a bitmask indicating which fields of the \p vinfo_template
+ * are to be matched.  The value must be \c VisualScreenMask.
+ * \param vinfo_template a template whose fields indicate which visual
+ * attributes must be matched by the results.  The XVisualInfo::screen field of
+ * this structure must be zero.
+ * \param nitens_return will hold the number of visuals returned.
+ *
+ * \return the address of an array of all available visuals.
+ * 
+ * An example of using XGetVisualInfo() to get all available visuals follows:
+ * 
+ * \code
+ * XVisualInfo vinfo_template, *results;
+ * int nitens_return;
+ * Display *dpy = XOpenDisplay(NULL);
+ * vinfo_template.screen = 0;
+ * results = XGetVisualInfo(dpy, VisualScreenMask, &vinfo_template, &nitens_return);
+ * \endcode
+ * 
+ * Returns the list of all ::XVisualInfo available, one per
+ * ::__GLcontextMode stored in MiniGLXDisplayRec::modes.
+ */
+XVisualInfo *
+XGetVisualInfo( Display *dpy, long vinfo_mask, XVisualInfo *vinfo_template, int *nitens_return )
+{
+   XVisualInfo *results;
+   Visual *visResults;
+   int i, n;
+
+   ASSERT(vinfo_mask == VisualScreenMask);
+   ASSERT(vinfo_template.screen == 0);
+
+   n = dpy->numModes;
+   results = (XVisualInfo *)calloc(1, n * sizeof(XVisualInfo));
+   if (!results) {
+      *nitens_return = 0;
+      return NULL;
+   }
+
+   visResults = (Visual *)calloc(1, n * sizeof(Visual));
+   if (!results) {
+      free(results);
+      *nitens_return = 0;
+      return NULL;
+   }
+
+   for (i = 0; i < n; i++) {
+      visResults[i].mode = dpy->modes + i;
+      visResults[i].visInfo = results + i;
+      visResults[i].dpy = dpy;
+
+      if (dpy->driverContext.bpp == 32)
+	 visResults[i].pixelFormat = PF_B8G8R8A8; /* XXX: FIX ME */
+      else
+	 visResults[i].pixelFormat = PF_B5G6R5; /* XXX: FIX ME */
+
+      results[i].visual = visResults + i;
+      results[i].visualid = i;
+      results[i].class = TrueColor;
+      results[i].depth = dpy->modes[i].redBits +
+                         dpy->modes[i].redBits +
+                         dpy->modes[i].redBits +
+                         dpy->modes[i].redBits;
+      results[i].bits_per_rgb = dpy->driverContext.bpp;
+   }
+   *nitens_return = n;
+   return results;
+}
+
+
+/**
+ * \brief Return a visual that matches specified attributes.
+ *
+ * \param dpy the display handle, as returned by XOpenDisplay().
+ * \param screen the screen number. It is currently ignored by Mini GLX and
+ * should be zero.
+ * \param attribList a list of GLX attributes which describe the desired pixel
+ * format. It is terminated by the token \c None. 
+ *
+ * The attributes are as follows:
+ * \arg GLX_USE_GL:
+ * This attribute should always be present in order to maintain compatibility
+ * with GLX.
+ * \arg GLX_RGBA:
+ * If present, only RGBA pixel formats will be considered. Otherwise, only
+ * color index formats are considered.
+ * \arg GLX_DOUBLEBUFFER:
+ * if present, only double-buffered pixel formats will be chosen.
+ * \arg GLX_RED_SIZE \e n:
+ * Must be followed by a non-negative integer indicating the minimum number of
+ * bits per red pixel component that is acceptable.
+ * \arg GLX_GREEN_SIZE \e n:
+ * Must be followed by a non-negative integer indicating the minimum number of
+ * bits per green pixel component that is acceptable.
+ * \arg GLX_BLUE_SIZE \e n:
+ * Must be followed by a non-negative integer indicating the minimum number of
+ * bits per blue pixel component that is acceptable.
+ * \arg GLX_ALPHA_SIZE \e n:
+ * Must be followed by a non-negative integer indicating the minimum number of
+ * bits per alpha pixel component that is acceptable.
+ * \arg GLX_STENCIL_SIZE \e n:
+ * Must be followed by a non-negative integer indicating the minimum number of
+ * bits per stencil value that is acceptable.
+ * \arg GLX_DEPTH_SIZE \e n:
+ * Must be followed by a non-negative integer indicating the minimum number of
+ * bits per depth component that is acceptable.
+ * \arg None:
+ * This token is used to terminate the attribute list.
+ *
+ * \return a pointer to an #XVisualInfo object which most closely matches the
+ * requirements of the attribute list. If there is no visual which matches the
+ * request, \c NULL will be returned.
+ *
+ * \note Visuals with accumulation buffers are not available.
+ *
+ * This function searches the list of available visual configurations in
+ * MiniGLXDisplayRec::configs for a configuration which best matches the GLX
+ * attribute list parameter.  A new ::XVisualInfo object is created which
+ * describes the visual configuration.  The match criteria is described in the
+ * specification.
+ */
+XVisualInfo*
+glXChooseVisual( Display *dpy, int screen, int *attribList )
+{
+   Visual *vis;
+   XVisualInfo *visInfo;
+   const int *attrib;
+   GLboolean rgbFlag = GL_FALSE, dbFlag = GL_FALSE, stereoFlag = GL_FALSE;
+   GLint redBits = 0, greenBits = 0, blueBits = 0, alphaBits = 0;
+   GLint indexBits = 0, depthBits = 0, stencilBits = 0;
+   GLint numSamples = 0;
+   int i;
+
+   /*
+    * XXX in the future, <screen> might be interpreted as a VT
+    */
+   ASSERT(dpy);
+   ASSERT(screen == 0);
+
+   vis = (Visual *)calloc(1, sizeof(Visual));
+   if (!vis)
+      return NULL;
+
+   visInfo = (XVisualInfo *)malloc(sizeof(XVisualInfo));
+   if (!visInfo) {
+      free(vis);
+      return NULL;
+   }
+
+   visInfo->visual = vis;
+   vis->visInfo = visInfo;
+   vis->dpy = dpy;
+
+   /* parse the attribute list */
+   for (attrib = attribList; attrib && *attrib != None; attrib++) {
+      switch (attrib[0]) {
+      case GLX_DOUBLEBUFFER:
+         dbFlag = GL_TRUE;
+         break;
+      case GLX_RGBA:
+         rgbFlag = GL_TRUE;
+         break;
+      case GLX_RED_SIZE:
+         redBits = attrib[1];
+         attrib++;
+         break;
+      case GLX_GREEN_SIZE:
+         redBits = attrib[1];
+         attrib++;
+         break;
+      case GLX_BLUE_SIZE:
+         redBits = attrib[1];
+         attrib++;
+         break;
+      case GLX_ALPHA_SIZE:
+         redBits = attrib[1];
+         attrib++;
+         break;
+      case GLX_STENCIL_SIZE:
+         stencilBits = attrib[1];
+         attrib++;
+         break;
+      case GLX_DEPTH_SIZE:
+         depthBits = attrib[1];
+         attrib++;
+         break;
+#if 0
+      case GLX_ACCUM_RED_SIZE:
+         accumRedBits = attrib[1];
+         attrib++;
+         break;
+      case GLX_ACCUM_GREEN_SIZE:
+         accumGreenBits = attrib[1];
+         attrib++;
+         break;
+      case GLX_ACCUM_BLUE_SIZE:
+         accumBlueBits = attrib[1];
+         attrib++;
+         break;
+      case GLX_ACCUM_ALPHA_SIZE:
+         accumAlphaBits = attrib[1];
+         attrib++;
+         break;
+      case GLX_LEVEL:
+         /* ignored for now */
+         break;
+#endif
+      default:
+         /* unexpected token */
+         fprintf(stderr, "unexpected token in glXChooseVisual attrib list\n");
+         free(vis);
+         free(visInfo);
+         return NULL;
+      }
+   }
+
+   /* search screen configs for suitable visual */
+   (void) numSamples;
+   (void) indexBits;
+   (void) redBits;
+   (void) greenBits;
+   (void) blueBits;
+   (void) alphaBits;
+   (void) stereoFlag;
+   for (i = 0; i < dpy->numModes; i++) {
+      const __GLcontextModes *mode = dpy->modes + i;
+      if (mode->rgbMode == rgbFlag &&
+          mode->redBits >= redBits &&
+          mode->greenBits >= greenBits &&
+          mode->blueBits >= blueBits &&
+          mode->alphaBits >= alphaBits &&
+          mode->depthBits >= depthBits &&
+          mode->stencilBits >= stencilBits) {
+         /* found it */
+         visInfo->visualid = i;
+         vis->mode = mode;
+         break;
+      }          
+   }
+   if (!vis->mode)
+       return NULL;
+
+   /* compute depth and bpp */
+   if (rgbFlag) {
+      /* XXX maybe support depth 16 someday */
+      visInfo->class = TrueColor;
+      visInfo->depth = dpy->driverContext.bpp;
+      visInfo->bits_per_rgb = dpy->driverContext.bpp;
+      if (dpy->driverContext.bpp == 32)
+	 vis->pixelFormat = PF_B8G8R8A8;
+      else
+	 vis->pixelFormat = PF_B5G6R5;
+   }
+   else {
+      /* color index mode */
+      visInfo->class = PseudoColor;
+      visInfo->depth = 8;
+      visInfo->bits_per_rgb = 8;  /* bits/pixel */
+      vis->pixelFormat = PF_CI8;
+   }
+
+   return visInfo;
+}
+
+
+/**
+ * \brief Return information about GLX visuals.
+ *
+ * \param dpy the display handle, as returned by XOpenDisplay().
+ * \param vis the visual to be queried, as returned by glXChooseVisual().
+ * \param attrib the visual attribute to be returned.
+ * \param value pointer to an integer in which the result of the query will be
+ * stored.
+ * 
+ * \return zero if no error occurs, \c GLX_INVALID_ATTRIBUTE if the attribute
+ * parameter is invalid, or \c GLX_BAD_VISUAL if the \p vis parameter is
+ * invalid.
+ *
+ * Returns the appropriate attribute of ::__GLXvisualConfig pointed by
+ * MiniGLXVisualRec::glxConfig of XVisualInfo::visual.
+ *
+ * \sa data types.
+ */
+int
+glXGetConfig( Display *dpy, XVisualInfo *vis, int attrib, int *value )
+{
+   const __GLcontextModes *mode = vis->visual->mode;
+   if (!mode) {
+      *value = 0;
+      return GLX_BAD_VISUAL;
+   }
+
+   switch (attrib) {
+   case GLX_USE_GL:
+      *value = True;
+      return 0;
+   case GLX_RGBA:
+      *value = mode->rgbMode;
+      return 0;
+   case GLX_DOUBLEBUFFER:
+      *value = mode->doubleBufferMode;
+      return 0;
+   case GLX_RED_SIZE:
+      *value = mode->redBits;
+      return 0;
+   case GLX_GREEN_SIZE:
+      *value = mode->greenBits;
+      return 0;
+   case GLX_BLUE_SIZE:
+      *value = mode->blueBits;
+      return 0;
+   case GLX_ALPHA_SIZE:
+      *value = mode->alphaBits;
+      return 0;
+   case GLX_DEPTH_SIZE:
+      *value = mode->depthBits;
+      return 0;
+   case GLX_STENCIL_SIZE:
+      *value = mode->stencilBits;
+      return 0;
+   default:
+      *value = 0;
+      return GLX_BAD_ATTRIBUTE;
+   }
+   return 0;
+}
+
+
+/**
+ * \brief Create a new GLX rendering context.
+ *
+ * \param dpy the display handle, as returned by XOpenDisplay().
+ * \param vis the visual that defines the frame buffer resources available to
+ * the rendering context, as returned by glXChooseVisual().
+ * \param shareList If non-zero, texture objects and display lists are shared
+ * with the named rendering context. If zero, texture objects and display lists
+ * will (initially) be private to this context. They may be shared when a
+ * subsequent context is created.
+ * \param direct whether direct or indirect rendering is desired. For Mini GLX
+ * this value is ignored but it should be set to \c True.
+ *
+ * \return a ::GLXContext handle if it succeeds or zero if it fails due to
+ * invalid parameter or insufficient resources.
+ *
+ * This function creates and initializes a ::MiniGLXContextRec structure and
+ * calls the __DRIscreenRec::createContext method to initialize the client
+ * private data.
+ */ 
+GLXContext
+glXCreateContext( Display *dpy, XVisualInfo *vis,
+                        GLXContext shareList, Bool direct )
+{
+   GLXContext ctx;
+   void *sharePriv;
+
+   ASSERT(vis);
+
+   ctx = (struct MiniGLXContextRec *)calloc(1, sizeof(struct MiniGLXContextRec));
+   if (!ctx)
+      return NULL;
+
+   ctx->vid = vis->visualid;
+ 
+   if (shareList)
+      sharePriv = shareList->driContext;
+   else
+      sharePriv = NULL;
+   
+   ctx->driContext = (*dpy->driScreen->createContext)(dpy->driScreen, 
+						      vis->visual->mode,
+						      sharePriv);
+   if (!ctx->driContext) {
+      free(ctx);
+      return NULL;
+   }
+
+   return ctx;
+}
+
+
+/**
+ * \brief Destroy a GLX context.
+ *
+ * \param dpy the display handle, as returned by XOpenDisplay().
+ * \param ctx the GLX context to be destroyed.
+ * 
+ * This function frees the \p ctx parameter after unbinding the current context
+ * by calling the __DRIcontextRec::bindContext method with zeros and calling
+ * the __DRIcontextRec::destroyContext method.
+ */
+void
+glXDestroyContext( Display *dpy, GLXContext ctx )
+{
+   GLXContext glxctx = glXGetCurrentContext();
+
+   if (ctx) {
+      if (glxctx == ctx) {
+         /* destroying current context */
+         (*ctx->driContext->bindContext)(dpy->driScreen, 0, 0);
+	 CurrentContext = 0;
+      }
+      (*ctx->driContext->destroyContext)(ctx->driContext);
+      free(ctx);
+   }
+}
+
+
+/**
+ * \brief Bind a GLX context to a window or a pixmap.
+ *
+ * \param dpy the display handle, as returned by XOpenDisplay().
+ * \param drawable the window or drawable to bind to the rendering context.
+ * This should be the value returned by XCreateWindow().
+ * \param ctx the GLX context to be destroyed.
+ *
+ * \return \c True if it succeeds, \c False otherwise to indicate an invalid
+ * display, window or context parameter.
+ *
+ * The current rendering context may be unbound by calling glXMakeCurrent()
+ * with the window and context parameters set to zero.
+ * 
+ * An application may create any number of rendering contexts and bind them as
+ * needed. Note that binding a rendering context is generally not a
+ * light-weight operation.  Most simple OpenGL applications create only one
+ * rendering context.
+ *
+ * This function first unbinds any old context via
+ * __DRIcontextRec::unbindContext and binds the new one via
+ * __DRIcontextRec::bindContext.
+ *
+ * If \p drawable is zero it unbinds the GLX context by calling
+ * __DRIcontextRec::bindContext with zeros.
+ */
+Bool
+glXMakeCurrent( Display *dpy, GLXDrawable drawable, GLXContext ctx)
+{
+   if (dpy && drawable && ctx) {
+      GLXContext oldContext = glXGetCurrentContext();
+      GLXDrawable oldDrawable = glXGetCurrentDrawable();
+      /* unbind old */
+      if (oldContext) {
+         (*oldContext->driContext->unbindContext)(oldDrawable->driDrawable, oldContext->driContext);
+      }
+      /* bind new */
+      CurrentContext = ctx;
+      (*ctx->driContext->bindContext)(dpy->driScreen, drawable->driDrawable, ctx->driContext);
+      ctx->drawBuffer = drawable;
+      ctx->curBuffer = drawable;
+   }
+   else if (ctx && dpy) {
+      /* unbind */
+      (*ctx->driContext->bindContext)(dpy->driScreen, 0, 0);
+   }
+   else if (dpy) {
+      CurrentContext = 0;	/* kw:  this seems to be intended??? */
+   }
+
+   return True;
+}
+
+
+/**
+ * \brief Exchange front and back buffers.
+ * 
+ * \param dpy the display handle, as returned by XOpenDisplay().
+ * \param drawable the drawable whose buffers are to be swapped.
+ * 
+ * Any pending rendering commands will be completed before the buffer swap
+ * takes place.
+ * 
+ * Calling glXSwapBuffers() on a window which is single-buffered has no effect.
+ *
+ * This function just calls the __DRIdrawableRec::swapBuffers method to do the
+ * work.
+ */
+void
+glXSwapBuffers( Display *dpy, GLXDrawable drawable )
+{
+   if (!dpy || !drawable)
+      return;
+
+   (*drawable->driDrawable->swapBuffers)(drawable->driDrawable);
+}
+
+
+/**
+ * \brief Return the current context
+ *
+ * \return the current context, as specified by glXMakeCurrent(), or zero if no
+ * context is currently bound.
+ *
+ * \sa glXCreateContext(), glXMakeCurrent()
+ *
+ * Returns the value of the ::CurrentContext global variable.
+ */
+GLXContext
+glXGetCurrentContext( void )
+{
+   return CurrentContext;
+}
+
+
+/**
+ * \brief Return the current drawable.
+ *
+ * \return the current drawable, as specified by glXMakeCurrent(), or zero if
+ * no drawable is currently bound.
+ *
+ * This function gets the current context via glXGetCurrentContext() and
+ * returns the MiniGLXContextRec::drawBuffer attribute.
+ */
+GLXDrawable
+glXGetCurrentDrawable( void )
+{
+   GLXContext glxctx = glXGetCurrentContext();
+   if (glxctx)
+      return glxctx->drawBuffer;
+   else
+      return NULL;
+}
+
+
+/**
+ * \brief Query function address.
+ *
+ * The glXGetProcAddress() function will return the address of any available
+ * OpenGL or Mini GLX function.
+ * 
+ * \param procName name of the function to be returned.
+ *
+ * \return If \p procName is a valid function name, a pointer to that function
+ * will be returned.  Otherwise, \c NULL will be returned.
+ *
+ * The purpose of glXGetProcAddress() is to facilitate using future extensions
+ * to OpenGL or Mini GLX. If a future version of the library adds new extension
+ * functions they'll be accessible via glXGetProcAddress(). The alternative is
+ * to hard-code calls to the new functions in the application but doing so will
+ * prevent linking the application with older versions of the library.
+ * 
+ * Returns the function address by looking up its name in a static (name,
+ * address) pair list.
+ */
+const void *
+glXGetProcAddress( const GLubyte *procName )
+{
+   struct name_address {
+      const char *name;
+      const void *func;
+   };
+   static const struct name_address functions[] = {
+      { "glXChooseVisual", (void *) glXChooseVisual },
+      { "glXCreateContext", (void *) glXCreateContext },
+      { "glXDestroyContext", (void *) glXDestroyContext },
+      { "glXMakeCurrent", (void *) glXMakeCurrent },
+      { "glXSwapBuffers", (void *) glXSwapBuffers },
+      { "glXGetCurrentContext", (void *) glXGetCurrentContext },
+      { "glXGetCurrentDrawable", (void *) glXGetCurrentDrawable },
+      { "glXGetProcAddress", (void *) glXGetProcAddress },
+      { "XOpenDisplay", (void *) XOpenDisplay },
+      { "XCloseDisplay", (void *) XCloseDisplay },
+      { "XCreateWindow", (void *) XCreateWindow },
+      { "XDestroyWindow", (void *) XDestroyWindow },
+      { "XMapWindow", (void *) XMapWindow },
+      { "XCreateColormap", (void *) XCreateColormap },
+      { "XFreeColormap", (void *) XFreeColormap },
+      { "XFree", (void *) XFree },
+      { "XGetVisualinfo", (void *) XGetVisualInfo },
+      { NULL, NULL }
+   };
+   const struct name_address *entry;
+   for (entry = functions; entry->name; entry++) {
+      if (strcmp(entry->name, (const char *) procName) == 0) {
+         return entry->func;
+      }
+   }
+   return _glapi_get_proc_address((const char *) procName);
+}
+
+
+/**
+ * \brief Query the Mini GLX version.
+ *
+ * \param dpy the display handle. It is currently ignored, but should be the
+ * value returned by XOpenDisplay().
+ * \param major receives the major version number of Mini GLX.
+ * \param minor receives the minor version number of Mini GLX.
+ *
+ * \return \c True if the function succeeds, \c False if the function fails due
+ * to invalid parameters.
+ *
+ * \sa #MINI_GLX_VERSION_1_0.
+ * 
+ * Returns the hard-coded Mini GLX version.
+ */
+Bool
+glXQueryVersion( Display *dpy, int *major, int *minor )
+{
+   (void) dpy;
+   *major = 1;
+   *minor = 0;
+   return True;
+}
+
+
+/*@}*/