diff --git a/winsup/cygwin/cygtls.cc b/winsup/cygwin/cygtls.cc
new file mode 100644
index 000000000..2734cf536
--- /dev/null
+++ b/winsup/cygwin/cygtls.cc
@@ -0,0 +1,125 @@
+/* cygtls.h
+
+   Copyright 2003 Red Hat, Inc.
+
+This software is a copyrighted work licensed under the terms of the
+Cygwin license.  Please consult the file "CYGWIN_LICENSE" for
+details. */
+
+#include "winsup.h"
+#include "thread.h"
+#include "cygtls.h"
+#include "assert.h"
+#include <syslog.h>
+
+static _threadinfo NO_COPY dummy_thread;
+_threadinfo NO_COPY *_last_thread = &dummy_thread;
+
+CRITICAL_SECTION NO_COPY _threadinfo::protect_linked_list;
+
+void
+_threadinfo::set_state (bool is_exception)
+{
+  initialized = CYGTLS_INITIALIZED + is_exception;
+}
+
+void
+_threadinfo::reset_exception ()
+{
+  if (initialized == CYGTLS_EXCEPTION)
+    {
+#ifdef DEBUGGING
+      debug_printf ("resetting stack after an exception stack %p, stackptr %p", stack, stackptr);
+#endif
+      set_state (false);
+      stackptr--;
+    }
+}
+
+/* Two calls to get the stack right... */
+void
+_threadinfo::call (DWORD (*func) (void *, void *), void *arg)
+{
+  char buf[CYGTLS_PADSIZE];
+  call2 (func, arg, buf);
+}
+
+void
+_threadinfo::call2 (DWORD (*func) (void *, void *), void *arg, void *buf)
+{
+  _my_tls.init_thread (buf);
+  ExitThread (func (arg, buf));
+}
+
+void
+_threadinfo::init ()
+{
+  InitializeCriticalSection (&protect_linked_list);
+}
+
+void
+_threadinfo::init_thread (void *x)
+{
+  if (x)
+    {
+      memset (this, 0, sizeof (*this));
+      stackptr = stack;
+      if (_GLOBAL_REENT)
+	{
+	  local_clib._stdin = _GLOBAL_REENT->_stdin;
+	  local_clib._stdout = _GLOBAL_REENT->_stdout;
+	  local_clib._stderr = _GLOBAL_REENT->_stderr;
+	  local_clib.__sdidinit = _GLOBAL_REENT->__sdidinit;
+	  local_clib.__cleanup = _GLOBAL_REENT->__cleanup;
+	}
+      local_clib._current_locale = "C";
+      locals.process_logmask = LOG_UPTO (LOG_DEBUG);
+    }
+
+  EnterCriticalSection (&protect_linked_list);
+  prev = _last_thread;
+  _last_thread->next = this;
+  _last_thread = this;
+  LeaveCriticalSection (&protect_linked_list);
+
+  set_state (false);
+  errno_addr = &(local_clib._errno);
+}
+
+void
+_threadinfo::remove ()
+{
+  EnterCriticalSection (&protect_linked_list);
+  if (prev)
+    {
+      prev->next = next;
+      if (next)
+	next->prev = prev;
+      if (this == _last_thread)
+	_last_thread = prev;
+      prev = next = NULL;
+    }
+  LeaveCriticalSection (&protect_linked_list);
+}
+
+void
+_threadinfo::push (__stack_t addr, bool exception)
+{
+  *stackptr++ = (__stack_t) addr;
+  set_state (exception);
+}
+
+__stack_t
+_threadinfo::pop ()
+{
+#ifdef DEBUGGING
+  assert (stackptr > stack);
+#endif
+  __stack_t res = *--stackptr;
+#ifdef DEBUGGING
+  *stackptr = 0;
+  debug_printf ("popped %p, stack %p, stackptr %p", res, stack, stackptr);
+#endif
+  return res;
+}
+