NEWS.stable: log cherry-pick [e446f25]->[c092018] relocatable-shell: Update suggested...

[gnulib.git] / lib / save-cwd.c

diff --git a/lib/save-cwd.c b/lib/save-cwd.c
index 7f1b30b..7aafacd 100644 (file)
--- a/lib/save-cwd.c
+++ b/lib/save-cwd.c
@@ -1,12 +1,12 @@
 /* save-cwd.c -- Save and restore current working directory.
 
-   Copyright (C) 1995, 1997, 1998, 2003, 2004, 2005 Free Software
+   Copyright (C) 1995, 1997-1998, 2003-2006, 2009-2014 Free Software
    Foundation, Inc.
 
-   This program is free software; you can redistribute it and/or modify
+   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
@@ -14,58 +14,44 @@
    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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
 
 /* Written by Jim Meyering.  */
 
-#ifdef HAVE_CONFIG_H
-# include <config.h>
-#endif
+#include <config.h>
 
 #include "save-cwd.h"
 
+#include <errno.h>
+#include <fcntl.h>
 #include <stdbool.h>
 #include <stdio.h>
 #include <stdlib.h>
 
-#if HAVE_UNISTD_H
-# include <unistd.h>
-#endif
-
-#include <fcntl.h>
-
-#include <errno.h>
-
 #include "chdir-long.h"
-#include "unistd-safer.h"
-#include "xgetcwd.h"
-
-/* On systems without the fchdir function (WOE), pretend that open
-   always returns -1 so that save_cwd resorts to using xgetcwd.
-   Since chdir_long requires fchdir, use chdir instead.  */
-#if !HAVE_FCHDIR
-# undef open
-# define open(File, Flags) (-1)
-# undef fchdir
-# define fchdir(Fd) (abort (), -1)
-# undef chdir_long
-# define chdir_long(Dir) chdir (Dir)
+#include "unistd--.h"
+#include "cloexec.h"
+
+#if GNULIB_FCNTL_SAFER
+# include "fcntl--.h"
+#else
+# define GNULIB_FCNTL_SAFER 0
 #endif
 
 /* Record the location of the current working directory in CWD so that
    the program may change to other directories and later use restore_cwd
    to return to the recorded location.  This function may allocate
-   space using malloc (via xgetcwd) or leave a file descriptor open;
+   space using malloc (via getcwd) or leave a file descriptor open;
    use free_cwd to perform the necessary free or close.  Upon failure,
    no memory is allocated, any locally opened file descriptors are
    closed;  return non-zero -- in that case, free_cwd need not be
    called, but doing so is ok.  Otherwise, return zero.
 
-   The `raison d'etre' for this interface is that the working directory
+   The _raison d'etre_ for this interface is that the working directory
    is sometimes inaccessible, and getcwd is not robust or as efficient.
    So, we prefer to use the open/fchdir approach, but fall back on
-   getcwd if necessary.
+   getcwd if necessary.  This module works for most cases with just
+   the getcwd-lgpl module, but to be truly robust, use the getcwd module.
 
    Some systems lack fchdir altogether: e.g., OS/2, pre-2001 Cygwin,
    SCO Xenix.  Also, SunOS 4 and Irix 5.3 provide the function, yet it
@@ -78,17 +64,16 @@ save_cwd (struct saved_cwd *cwd)
 {
   cwd->name = NULL;
 
-  cwd->desc = fd_safer (open (".", O_RDONLY));
+  cwd->desc = open (".", O_SEARCH);
+  if (!GNULIB_FCNTL_SAFER)
+    cwd->desc = fd_safer (cwd->desc);
   if (cwd->desc < 0)
     {
-      cwd->desc = fd_safer (open (".", O_WRONLY));
-      if (cwd->desc < 0)
-       {
-         cwd->name = xgetcwd ();
-         return cwd->name ? 0 : -1;
-       }
+      cwd->name = getcwd (NULL, 0);
+      return cwd->name ? 0 : -1;
     }
 
+  set_cloexec_flag (cwd->desc, true);
   return 0;
 }
 
@@ -110,6 +95,5 @@ free_cwd (struct saved_cwd *cwd)
 {
   if (cwd->desc >= 0)
     close (cwd->desc);
-  if (cwd->name)
-    free (cwd->name);
+  free (cwd->name);
 }