NaCl: Make fdopendir skip fcntl check.

ChangeLog

@@ -1,5 +1,7 @@
 2015-05-13  Roland McGrath  <roland@hack.frob.com>
 
+	* sysdeps/nacl/fdopendir.c: New file.
+
 	* dirent/scandir-tail.c: New file.
 	* dirent/scandir64-tail.c: New file.
 	* dirent/Makefile (routines): Add them.

sysdeps/nacl/fdopendir.c

@@ -0,0 +1,32 @@
+/* Open a directory stream from a file descriptor.  NaCl version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <assert.h>
+#include <fcntl.h>
+
+/* Since NaCl does not have a useful fcntl, stub it out.
+   fdopendir will not detect an fd open for writing only,
+   but readdir will fail with EBADF so that's close enough.  */
+
+#define __fcntl(fd, command)                    \
+  ({                                            \
+    assert ((command) == F_GETFL);              \
+    O_RDONLY;                                   \
+  })
+
+#include <sysdeps/posix/fdopendir.c>