add warnings to selinux-h module's configure macros

[gnulib.git] / lib / lchown.c

diff --git a/lib/lchown.c b/lib/lchown.c
index 9604b54..07aef87 100644 (file)
--- a/lib/lchown.c
+++ b/lib/lchown.c
@@ -1,10 +1,12 @@
 /* Provide a stub lchown function for systems that lack it.
-   Copyright (C) 1998, 1999 Free Software Foundation, Inc.
 
-   This program is free software; you can redistribute it and/or modify
+   Copyright (C) 1998, 1999, 2002, 2004, 2006, 2007 Free Software
+   Foundation, Inc.
+
+   This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
-   the Free Software Foundation; either version 2, or (at your option)
-   any later version.
+   the Free Software Foundation; either version 3 of the License, 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
@@ -12,45 +14,49 @@
    GNU General Public License for more details.
 
    You should have received a copy of the GNU General Public License
-   along with this program; if not, write to the Free Software Foundation,
-   Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
 
 /* written by Jim Meyering */
 
 #include <config.h>
 
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <errno.h>
-#ifndef errno
-extern int errno;
+/* If the system chown does not follow symlinks, we don't want it
+   replaced by gnulib's chown, which does follow symlinks.  */
+#if CHOWN_MODIFIES_SYMLINK
+# define REPLACE_CHOWN 0
 #endif
-#include "lchown.h"
+#include <unistd.h>
 
-#ifdef STAT_MACROS_BROKEN
-# undef S_ISLNK
-#endif
-#if !defined(S_ISLNK) && defined(S_IFLNK)
-# define S_ISLNK(m) (((m) & S_IFMT) == S_IFLNK)
-#endif
+#include <errno.h>
+#include <sys/stat.h>
 
-/* Declare chown to avoid a warning.  Don't include unistd.h,
-   because it may have a conflicting prototype for lchown.  */
-int chown ();
+/* Some systems don't have EOPNOTSUPP.  */
+#ifndef EOPNOTSUPP
+# ifdef ENOTSUP
+#  define EOPNOTSUPP ENOTSUP
+# else
+/* Some systems don't have ENOTSUP either.  */
+#  define EOPNOTSUPP EINVAL
+# endif
+#endif
 
 /* Work just like chown, except when FILE is a symbolic link.
-   In that case, set errno to ENOSYS and return -1.  */
+   In that case, set errno to EOPNOTSUPP and return -1.
+   But if autoconf tests determined that chown modifies
+   symlinks, then just call chown.  */
 
 int
 lchown (const char *file, uid_t uid, gid_t gid)
 {
+#if ! CHOWN_MODIFIES_SYMLINK
   struct stat stats;
 
   if (lstat (file, &stats) == 0 && S_ISLNK (stats.st_mode))
     {
-      errno = ENOSYS;
+      errno = EOPNOTSUPP;
       return -1;
     }
+#endif
 
   return chown (file, uid, gid);
 }