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diff --git a/src/mapi/u_current.c b/src/mapi/u_current.c
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+/*
+ * Mesa 3-D graphics library
+ * Version:  7.1
+ *
+ * Copyright (C) 1999-2008  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.
+ */
+
+
+/*
+ * This file manages the OpenGL API dispatch layer.
+ * The dispatch table (struct _glapi_table) is basically just a list
+ * of function pointers.
+ * There are functions to set/get the current dispatch table for the
+ * current thread and to manage registration/dispatch of dynamically
+ * added extension functions.
+ *
+ * It's intended that this file and the other glapi*.[ch] files are
+ * flexible enough to be reused in several places:  XFree86, DRI-
+ * based libGL.so, and perhaps the SGI SI.
+ *
+ * NOTE: There are no dependencies on Mesa in this code.
+ *
+ * Versions (API changes):
+ *   2000/02/23  - original version for Mesa 3.3 and XFree86 4.0
+ *   2001/01/16  - added dispatch override feature for Mesa 3.5
+ *   2002/06/28  - added _glapi_set_warning_func(), Mesa 4.1.
+ *   2002/10/01  - _glapi_get_proc_address() will now generate new entrypoints
+ *                 itself (using offset ~0).  _glapi_add_entrypoint() can be
+ *                 called afterward and it'll fill in the correct dispatch
+ *                 offset.  This allows DRI libGL to avoid probing for DRI
+ *                 drivers!  No changes to the public glapi interface.
+ */
+
+#include "u_current.h"
+#include "u_thread.h"
+
+#ifndef MAPI_MODE_UTIL
+
+#include "table.h"
+#include "stub.h"
+
+#else
+
+extern void init_glapi_relocs_once(void);
+extern void (*__glapi_noop_table[])(void);
+
+#define table_noop_array __glapi_noop_table
+#define stub_init_once() init_glapi_relocs_once()
+
+#endif
+
+/**
+ * \name Current dispatch and current context control variables
+ *
+ * Depending on whether or not multithreading is support, and the type of
+ * support available, several variables are used to store the current context
+ * pointer and the current dispatch table pointer.  In the non-threaded case,
+ * the variables \c _glapi_Dispatch and \c _glapi_Context are used for this
+ * purpose.
+ *
+ * In the "normal" threaded case, the variables \c _glapi_Dispatch and
+ * \c _glapi_Context will be \c NULL if an application is detected as being
+ * multithreaded.  Single-threaded applications will use \c _glapi_Dispatch
+ * and \c _glapi_Context just like the case without any threading support.
+ * When \c _glapi_Dispatch and \c _glapi_Context are \c NULL, the thread state
+ * data \c _gl_DispatchTSD and \c ContextTSD are used.  Drivers and the
+ * static dispatch functions access these variables via \c _glapi_get_dispatch
+ * and \c _glapi_get_context.
+ *
+ * There is a race condition in setting \c _glapi_Dispatch to \c NULL.  It is
+ * possible for the original thread to be setting it at the same instant a new
+ * thread, perhaps running on a different processor, is clearing it.  Because
+ * of that, \c ThreadSafe, which can only ever be changed to \c GL_TRUE, is
+ * used to determine whether or not the application is multithreaded.
+ * 
+ * In the TLS case, the variables \c _glapi_Dispatch and \c _glapi_Context are
+ * hardcoded to \c NULL.  Instead the TLS variables \c _glapi_tls_Dispatch and
+ * \c _glapi_tls_Context are used.  Having \c _glapi_Dispatch and
+ * \c _glapi_Context be hardcoded to \c NULL maintains binary compatability
+ * between TLS enabled loaders and non-TLS DRI drivers.
+ */
+/*@{*/
+#if defined(GLX_USE_TLS)
+
+__thread struct mapi_table *u_current_table
+    __attribute__((tls_model("initial-exec")))
+    = (struct mapi_table *) table_noop_array;
+
+__thread void *u_current_user
+    __attribute__((tls_model("initial-exec")));
+
+#else
+
+struct mapi_table *u_current_table =
+   (struct mapi_table *) table_noop_array;
+void *u_current_user;
+
+#ifdef THREADS
+struct u_tsd u_current_table_tsd;
+static struct u_tsd u_current_user_tsd;
+static int ThreadSafe;
+#endif /* THREADS */
+
+#endif /* defined(GLX_USE_TLS) */
+/*@}*/
+
+
+void
+u_current_destroy(void)
+{
+#if defined(THREADS) && defined(_WIN32)
+   u_tsd_destroy(&u_current_table_tsd);
+   u_tsd_destroy(&u_current_user_tsd);
+#endif
+}
+
+
+#if defined(THREADS) && !defined(GLX_USE_TLS)
+
+static void
+u_current_init_tsd(void)
+{
+   u_tsd_init(&u_current_table_tsd);
+   u_tsd_init(&u_current_user_tsd);
+}
+
+/**
+ * Mutex for multithread check.
+ */
+u_mutex_declare_static(ThreadCheckMutex);
+
+/**
+ * We should call this periodically from a function such as glXMakeCurrent
+ * in order to test if multiple threads are being used.
+ */
+void
+u_current_init(void)
+{
+   static unsigned long knownID;
+   static int firstCall = 1;
+
+   if (ThreadSafe)
+      return;
+
+   u_mutex_lock(ThreadCheckMutex);
+   if (firstCall) {
+      u_current_init_tsd();
+
+      knownID = u_thread_self();
+      firstCall = 0;
+   }
+   else if (knownID != u_thread_self()) {
+      ThreadSafe = 1;
+      u_current_set(NULL);
+      u_current_set_user(NULL);
+   }
+   u_mutex_unlock(ThreadCheckMutex);
+}
+
+#else
+
+void
+u_current_init(void)
+{
+}
+
+#endif
+
+
+
+/**
+ * Set the current context pointer for this thread.
+ * The context pointer is an opaque type which should be cast to
+ * void from the real context pointer type.
+ */
+void
+u_current_set_user(const void *ptr)
+{
+   u_current_init();
+
+#if defined(GLX_USE_TLS)
+   u_current_user = (void *) ptr;
+#elif defined(THREADS)
+   u_tsd_set(&u_current_user_tsd, (void *) ptr);
+   u_current_user = (ThreadSafe) ? NULL : (void *) ptr;
+#else
+   u_current_user = (void *) ptr;
+#endif
+}
+
+/**
+ * Get the current context pointer for this thread.
+ * The context pointer is an opaque type which should be cast from
+ * void to the real context pointer type.
+ */
+void *
+u_current_get_user_internal(void)
+{
+#if defined(GLX_USE_TLS)
+   return u_current_user;
+#elif defined(THREADS)
+   return (ThreadSafe)
+      ? u_tsd_get(&u_current_user_tsd)
+      : u_current_user;
+#else
+   return u_current_user;
+#endif
+}
+
+/**
+ * Set the global or per-thread dispatch table pointer.
+ * If the dispatch parameter is NULL we'll plug in the no-op dispatch
+ * table (__glapi_noop_table).
+ */
+void
+u_current_set(const struct mapi_table *tbl)
+{
+   u_current_init();
+
+   stub_init_once();
+
+   if (!tbl)
+      tbl = (const struct mapi_table *) table_noop_array;
+
+#if defined(GLX_USE_TLS)
+   u_current_table = (struct mapi_table *) tbl;
+#elif defined(THREADS)
+   u_tsd_set(&u_current_table_tsd, (void *) tbl);
+   u_current_table = (ThreadSafe) ? NULL : (void *) tbl;
+#else
+   u_current_table = (struct mapi_table *) tbl;
+#endif
+}
+
+/**
+ * Return pointer to current dispatch table for calling thread.
+ */
+struct mapi_table *
+u_current_get_internal(void)
+{
+#if defined(GLX_USE_TLS)
+   return u_current_table;
+#elif defined(THREADS)
+   return (struct mapi_table *) ((ThreadSafe) ?
+         u_tsd_get(&u_current_table_tsd) : (void *) u_current_table);
+#else
+   return u_current_table;
+#endif
+}