--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2005-08-24  Bruno Haible  <bruno@clisp.org>
+
+	* modules/tls-tests: New file.
+	* tests/test-tls.c: New file, from GNU gettext.
+
 2005-08-24  Bruno Haible  <bruno@clisp.org>
 
 	* modules/lock-tests: New file.

new file mode 100644
--- /dev/null
+++ b/modules/tls-tests
@@ -0,0 +1,20 @@
+Files:
+tests/test-tls.c
+
+Depends-on:
+
+configure.ac:
+dnl Checks for special libraries for the tests/test-tls test.
+dnl On some systems, sched_yield is in librt, rather than in libpthread.
+LIBSCHED=
+if test $gl_threads_api = posix; then
+  AC_CHECK_LIB(rt, sched_yield, [LIBSCHED=-lrt])
+fi
+AC_SUBST([LIBSCHED])
+
+Makefile.am:
+TESTS += test-tls
+noinst_PROGRAMS += test-tls
+test_tls_SOURCES = test-tls.c
+test_tls_LDADD = @LIBMULTITHREAD@ @LIBSCHED@ $(LDADD)
+

new file mode 100644
--- /dev/null
+++ b/tests/test-tls.c
@@ -0,0 +1,327 @@
+/* Test of thread-local storage in multithreaded situations.
+   Copyright (C) 2005 Free Software Foundation, Inc.
+
+   This program is free software; you can redistribute it and/or modify it
+   under the terms of the GNU Library General Public License as published
+   by the Free Software Foundation; either version 2, or (at your option)
+   any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with this program; if not, write to the Free Software
+   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
+   USA.  */
+
+/* Written by Bruno Haible <bruno@clisp.org>, 2005.  */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#if USE_POSIX_THREADS || USE_SOLARIS_THREADS || USE_PTH_THREADS || USE_WIN32_THREADS
+
+#if USE_POSIX_THREADS
+# define TEST_POSIX_THREADS 1
+#endif
+#if USE_SOLARIS_THREADS
+# define TEST_SOLARIS_THREADS 1
+#endif
+#if USE_PTH_THREADS
+# define TEST_PTH_THREADS 1
+#endif
+#if USE_WIN32_THREADS
+# define TEST_WIN32_THREADS 1
+#endif
+
+/* Whether to help the scheduler through explicit yield().
+   Uncomment this to see if the operating system has a fair scheduler.  */
+#define EXPLICIT_YIELD 1
+
+/* Whether to print debugging messages.  */
+#define ENABLE_DEBUGGING 0
+
+/* Number of simultaneous threads.  */
+#define THREAD_COUNT 16
+
+/* Number of operations performed in each thread.  */
+#define REPEAT_COUNT 50000
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "tls.h"
+
+#if ENABLE_DEBUGGING
+# define dbgprintf printf
+#else
+# define dbgprintf if (0) printf
+#endif
+
+#if TEST_POSIX_THREADS
+# include <pthread.h>
+# include <sched.h>
+typedef pthread_t gl_thread_t;
+static inline gl_thread_t gl_thread_create (void * (*func) (void *), void *arg)
+{
+  pthread_t thread;
+  if (pthread_create (&thread, NULL, func, arg) != 0)
+    abort ();
+  return thread;
+}
+static inline void gl_thread_join (gl_thread_t thread)
+{
+  void *retval;
+  if (pthread_join (thread, &retval) != 0)
+    abort ();
+}
+static inline void gl_thread_yield (void)
+{
+  sched_yield ();
+}
+static inline void * gl_thread_self (void)
+{
+  return (void *) pthread_self ();
+}
+#endif
+#if TEST_PTH_THREADS
+# include <pth.h>
+typedef pth_t gl_thread_t;
+static inline gl_thread_t gl_thread_create (void * (*func) (void *), void *arg)
+{
+  pth_t thread = pth_spawn (NULL, func, arg);
+  if (thread == NULL)
+    abort ();
+  return thread;
+}
+static inline void gl_thread_join (gl_thread_t thread)
+{
+  if (!pth_join (thread, NULL))
+    abort ();
+}
+static inline void gl_thread_yield (void)
+{
+  pth_yield (NULL);
+}
+static inline void * gl_thread_self (void)
+{
+  return pth_self ();
+}
+#endif
+#if TEST_SOLARIS_THREADS
+# include <thread.h>
+typedef thread_t gl_thread_t;
+static inline gl_thread_t gl_thread_create (void * (*func) (void *), void *arg)
+{
+  thread_t thread;
+  if (thr_create (NULL, 0, func, arg, 0, &thread) != 0)
+    abort ();
+  return thread;
+}
+static inline void gl_thread_join (gl_thread_t thread)
+{
+  void *retval;
+  if (thr_join (thread, NULL, &retval) != 0)
+    abort ();
+}
+static inline void gl_thread_yield (void)
+{
+  thr_yield ();
+}
+static inline void * gl_thread_self (void)
+{
+  return (void *) thr_self ();
+}
+#endif
+#if TEST_WIN32_THREADS
+# include <windows.h>
+typedef HANDLE gl_thread_t;
+/* Use a wrapper function, instead of adding WINAPI through a cast.  */
+struct wrapper_args { void * (*func) (void *); void *arg; };
+static DWORD WINAPI wrapper_func (void *varg)
+{
+  struct wrapper_args *warg = (struct wrapper_args *)varg;
+  void * (*func) (void *) = warg->func;
+  void *arg = warg->arg;
+  free (warg);
+  func (arg);
+  return 0;
+}
+static inline gl_thread_t gl_thread_create (void * (*func) (void *), void *arg)
+{
+  struct wrapper_args *warg =
+    (struct wrapper_args *) malloc (sizeof (struct wrapper_args));
+  if (warg == NULL)
+    abort ();
+  warg->func = func;
+  warg->arg = arg;
+  {
+    DWORD thread_id;
+    HANDLE thread =
+      CreateThread (NULL, 100000, wrapper_func, warg, 0, &thread_id);
+    if (thread == NULL)
+      abort ();
+    return thread;
+  }
+}
+static inline void gl_thread_join (gl_thread_t thread)
+{
+  if (WaitForSingleObject (thread, INFINITE) == WAIT_FAILED)
+    abort ();
+  if (!CloseHandle (thread))
+    abort ();
+}
+static inline void gl_thread_yield (void)
+{
+  Sleep (0);
+}
+static inline void * gl_thread_self (void)
+{
+  return (void *) GetCurrentThreadId ();
+}
+#endif
+#if EXPLICIT_YIELD
+# define yield() gl_thread_yield ()
+#else
+# define yield()
+#endif
+
+static inline void
+perhaps_yield (void)
+{
+  /* Call yield () only with a certain probability, otherwise with GNU Pth
+     the sequence of thread activations is too predictable.  */
+  if ((((unsigned int) rand () >> 3) % 4) == 0)
+    yield ();
+}
+
+#define KEYS_COUNT 4
+
+static gl_tls_key_t mykeys[KEYS_COUNT];
+
+static void *
+worker_thread (void *arg)
+{
+  unsigned int id = (unsigned int) (unsigned long) arg;
+  int i, j, repeat;
+  unsigned int values[KEYS_COUNT];
+
+  dbgprintf ("Worker %p started\n", gl_thread_self ());
+
+  /* Initialize the per-thread storage.  */
+  for (i = 0; i < KEYS_COUNT; i++)
+    {
+      values[i] = (((unsigned int) rand() >> 3) % 1000000) * THREAD_COUNT + id;
+      /* Hopefully no arithmetic overflow.  */
+      if ((values[i] % THREAD_COUNT) != id)
+	abort ();
+    }
+  perhaps_yield ();
+
+  /* Verify that the initial value is NULL.  */
+  dbgprintf ("Worker %p before initial verify\n", gl_thread_self ());
+  for (i = 0; i < KEYS_COUNT; i++)
+    if (gl_tls_get (mykeys[i]) != NULL)
+      abort ();
+  dbgprintf ("Worker %p after  initial verify\n", gl_thread_self ());
+  perhaps_yield ();
+
+  /* Initialize the per-thread storage.  */
+  dbgprintf ("Worker %p before first tls_set\n", gl_thread_self ());
+  for (i = 0; i < KEYS_COUNT; i++)
+    {
+      unsigned int *ptr = (unsigned int *) malloc (sizeof (unsigned int));
+      *ptr = values[i];
+      gl_tls_set (mykeys[i], ptr);
+    }
+  dbgprintf ("Worker %p after  first tls_set\n", gl_thread_self ());
+  perhaps_yield ();
+
+  /* Shuffle around the pointers.  */
+  for (repeat = REPEAT_COUNT; repeat > 0; repeat--)
+    {
+      dbgprintf ("Worker %p doing value swapping\n", gl_thread_self ());
+      i = ((unsigned int) rand() >> 3) % KEYS_COUNT;
+      j = ((unsigned int) rand() >> 3) % KEYS_COUNT;
+      if (i != j)
+	{
+	  void *vi = gl_tls_get (mykeys[i]);
+	  void *vj = gl_tls_get (mykeys[j]);
+
+	  gl_tls_set (mykeys[i], vj);
+	  gl_tls_set (mykeys[j], vi);
+	}
+      perhaps_yield ();
+    }
+
+  /* Verify that all the values are from this thread.  */
+  dbgprintf ("Worker %p before final verify\n", gl_thread_self ());
+  for (i = 0; i < KEYS_COUNT; i++)
+    if ((*(unsigned int *) gl_tls_get (mykeys[i]) % THREAD_COUNT) != id)
+      abort ();
+  dbgprintf ("Worker %p after  final verify\n", gl_thread_self ());
+  perhaps_yield ();
+
+  dbgprintf ("Worker %p dying.\n", gl_thread_self ());
+  return NULL;
+}
+
+void
+test_tls (void)
+{
+  int pass, i;
+
+  for (pass = 0; pass < 2; pass++)
+    {
+      gl_thread_t threads[THREAD_COUNT];
+
+      if (pass == 0)
+	for (i = 0; i < KEYS_COUNT; i++)
+	  gl_tls_key_init (mykeys[i], free);
+      else
+	for (i = KEYS_COUNT - 1; i >= 0; i--)
+	  gl_tls_key_init (mykeys[i], free);
+
+      /* Spawn the threads.  */
+      for (i = 0; i < THREAD_COUNT; i++)
+	threads[i] = gl_thread_create (worker_thread, NULL);
+
+      /* Wait for the threads to terminate.  */
+      for (i = 0; i < THREAD_COUNT; i++)
+	gl_thread_join (threads[i]);
+
+      for (i = 0; i < KEYS_COUNT; i++)
+	gl_tls_key_destroy (mykeys[i]);
+    }
+}
+
+int
+main ()
+{
+#if TEST_PTH_THREADS
+  if (!pth_init ())
+    abort ();
+#endif
+
+  printf ("Starting test_tls ..."); fflush (stdout);
+  test_tls ();
+  printf (" OK\n"); fflush (stdout);
+
+  return 0;
+}
+
+#else
+
+/* No multithreading available.  */
+
+int
+main ()
+{
+  return 77;
+}
+
+#endif