--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/libiberty/fopen_unlocked.c	Fri Jul 17 14:47:48 2009 +0900
@@ -0,0 +1,126 @@
+/* Implement fopen_unlocked and related functions.
+   Copyright (C) 2005 Free Software Foundation, Inc.
+   Written by Kaveh R. Ghazi <ghazi@caip.rutgers.edu>.
+
+This file is part of the libiberty library.
+Libiberty 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 of the License, or (at your option) any later version.
+
+Libiberty 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 libiberty; see the file COPYING.LIB.  If
+not, write to the Free Software Foundation, Inc., 51 Franklin Street - Fifth Floor,
+Boston, MA 02110-1301, USA.  */
+
+/*
+
+@deftypefn Extension void unlock_stream (FILE * @var{stream})
+
+If the OS supports it, ensure that the supplied stream is setup to
+avoid any multi-threaded locking.  Otherwise leave the @code{FILE}
+pointer unchanged.  If the @var{stream} is @code{NULL} do nothing.
+
+@end deftypefn
+
+@deftypefn Extension void unlock_std_streams (void)
+
+If the OS supports it, ensure that the standard I/O streams,
+@code{stdin}, @code{stdout} and @code{stderr} are setup to avoid any
+multi-threaded locking.  Otherwise do nothing.
+
+@end deftypefn
+
+@deftypefn Extension {FILE *} fopen_unlocked (const char *@var{path}, const char * @var{mode})
+
+Opens and returns a @code{FILE} pointer via @code{fopen}.  If the
+operating system supports it, ensure that the stream is setup to avoid
+any multi-threaded locking.  Otherwise return the @code{FILE} pointer
+unchanged.
+
+@end deftypefn
+
+@deftypefn Extension {FILE *} fdopen_unlocked (int @var{fildes}, const char * @var{mode})
+
+Opens and returns a @code{FILE} pointer via @code{fdopen}.  If the
+operating system supports it, ensure that the stream is setup to avoid
+any multi-threaded locking.  Otherwise return the @code{FILE} pointer
+unchanged.
+
+@end deftypefn
+
+@deftypefn Extension {FILE *} freopen_unlocked (const char * @var{path}, const char * @var{mode}, FILE * @var{stream})
+
+Opens and returns a @code{FILE} pointer via @code{freopen}.  If the
+operating system supports it, ensure that the stream is setup to avoid
+any multi-threaded locking.  Otherwise return the @code{FILE} pointer
+unchanged.
+
+@end deftypefn
+
+*/
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+#include <stdio.h>
+#ifdef HAVE_STDIO_EXT_H
+#include <stdio_ext.h>
+#endif
+
+#include "libiberty.h"
+
+/* This is an inline helper function to consolidate attempts to unlock
+   a stream.  */
+
+static inline void
+unlock_1 (FILE *const fp ATTRIBUTE_UNUSED)
+{
+#if defined(HAVE___FSETLOCKING) && defined(FSETLOCKING_BYCALLER)
+  if (fp)
+    __fsetlocking (fp, FSETLOCKING_BYCALLER);
+#endif
+}
+
+void
+unlock_stream (FILE *fp)
+{
+  unlock_1 (fp);
+}
+
+void
+unlock_std_streams (void)
+{
+  unlock_1 (stdin);
+  unlock_1 (stdout);
+  unlock_1 (stderr);
+}
+
+FILE *
+fopen_unlocked (const char *path, const char *mode)		
+{
+  FILE *const fp = fopen (path, mode);
+  unlock_1 (fp);
+  return fp;
+}
+
+FILE *
+fdopen_unlocked (int fildes, const char *mode)
+{
+  FILE *const fp = fdopen (fildes, mode);
+  unlock_1 (fp);
+  return fp;
+}
+
+FILE *
+freopen_unlocked (const char *path, const char *mode, FILE *stream)
+{
+  FILE *const fp = freopen (path, mode, stream);
+  unlock_1 (fp);
+  return fp;
+}