* sysdeps/unix/fdopendir.c (fdopendir): If O_DIRECTORY is

available, avoid stat call, use fcntl result to determine whether
	descriptor is for a directory or not.
	* dirent/Makefile (tests): Add tst-fdopendir2.
	* dirent/tst-fdopendir2.c: New file.

ChangeLog

@@ -1,3 +1,11 @@
+2006-01-20  Ulrich Drepper  <drepper@redhat.com>
+
+	* sysdeps/unix/fdopendir.c (fdopendir): If O_DIRECTORY is
+	available, avoid stat call, use fcntl result to determine whether
+	descriptor is for a directory or not.
+	* dirent/Makefile (tests): Add tst-fdopendir2.
+	* dirent/tst-fdopendir2.c: New file.
+
 2006-01-20  Alexandre Oliva  <aoliva@redhat.com>
 
 	* sysdeps/unix/sysv/linux/x86_64/bits/sigcontext.h

dirent/Makefile

@@ -1,4 +1,4 @@
-# Copyright (C) 1991-2000, 2002, 2003, 2005 Free Software Foundation, Inc.
+# Copyright (C) 1991-2000,2002,2003,2005,2006 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
@@ -28,7 +28,8 @@ routines	:= opendir closedir readdir readdir_r rewinddir \
 		   alphasort64 versionsort64 fdopendir
 distribute := dirstream.h
 
-tests	   := list tst-seekdir opendir-tst1 bug-readdir1 tst-fdopendir
+tests	   := list tst-seekdir opendir-tst1 bug-readdir1 tst-fdopendir \
+	      tst-fdopendir2
 
 CFLAGS-scandir.c = $(uses-callbacks)
 CFLAGS-scandir64.c = $(uses-callbacks)

dirent/tst-fdopendir2.c

@@ -0,0 +1,41 @@
+#include <errno.h>
+#include <dirent.h>
+#include <stdio.h>
+#include <unistd.h>
+
+
+static int
+do_test (void)
+{
+  char tmpl[] = "/tmp/tst-fdopendir2-XXXXXX";
+  int fd = mkstemp (tmpl);
+  if (fd == -1)
+    {
+      puts ("cannot open temp file");
+      return 1;
+    }
+
+  errno = 0;
+  DIR *d = fdopendir (fd);
+
+  int e = errno;
+
+  close (fd);
+  unlink (tmpl);
+
+  if (d != NULL)
+    {
+      puts ("fdopendir with normal file descriptor did not fail");
+      return 1;
+    }
+  if (e != ENOTDIR)
+    {
+      printf ("fdopendir set errno to %d, not %d as expected\n", e, ENOTDIR);
+      return 1;
+    }
+
+  return 0;
+}
+
+#define TEST_FUNCTION do_test ()
+#include "../test-skeleton.c"

sysdeps/unix/fdopendir.c

@@ -1,4 +1,4 @@
-/* Copyright (C) 2005 Free Software Foundation, Inc.
+/* Copyright (C) 2005, 2006 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
@@ -29,6 +29,7 @@ fdopendir (int fd)
 {
   struct stat64 statbuf;
 
+#ifndef O_DIRECTORY
   if (__builtin_expect (__fxstat64 (_STAT_VER, fd, &statbuf), 0) < 0)
     return NULL;
   if (__builtin_expect (! S_ISDIR (statbuf.st_mode), 0))
@@ -36,10 +37,20 @@ fdopendir (int fd)
       __set_errno (ENOTDIR);
       return NULL;
     }
-  /* Make sure the descriptor allows for reading.  */
+#endif
+
+  /* Make sure the descriptor allows for reading (and eventually that
+     the descriptor is for a directory).  */
   int flags = __fcntl (fd, F_GETFL);
   if (__builtin_expect (flags == -1, 0))
     return NULL;
+#ifdef O_DIRECTORY
+  if (__builtin_expect ((flags & O_DIRECTORY) == 0, 0))
+    {
+      __set_errno (ENOTDIR);
+      return NULL;
+    }
+#endif
   if (__builtin_expect ((flags & O_ACCMODE) == O_WRONLY, 0))
     {
       __set_errno (EINVAL);