X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=lib%2Fsave-cwd.c;h=9ae37b08d30ae9f406269e9673ba4c7ba3d3b120;hb=75a6c62f09fc5b5282a5f763438e891838bb7164;hp=272f7421e9080c88323818b7c08f2c776e2d1e96;hpb=d9203c96c70e64ae24a2f2d36e1ba80d79628dc5;p=gnulib.git diff --git a/lib/save-cwd.c b/lib/save-cwd.c index 272f7421e..9ae37b08d 100644 --- a/lib/save-cwd.c +++ b/lib/save-cwd.c @@ -1,10 +1,12 @@ /* save-cwd.c -- Save and restore current working directory. - Copyright (C) 1995, 1997, 1998, 2003, 2004 Free Software Foundation, Inc. - This program is free software; you can redistribute it and/or modify + Copyright (C) 1995, 1997-1998, 2003-2006, 2009-2013 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 @@ -12,107 +14,66 @@ 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 . */ /* Written by Jim Meyering. */ -#if HAVE_CONFIG_H -# include "config.h" -#endif +#include #include "save-cwd.h" +#include +#include #include #include #include -#if HAVE_UNISTD_H -# include -#endif +#include "chdir-long.h" +#include "unistd--.h" +#include "cloexec.h" -#if HAVE_FCNTL_H -# include +#if GNULIB_FCNTL_SAFER +# include "fcntl--.h" #else -# include +# define GNULIB_FCNTL_SAFER 0 #endif -#include - -#include "chdir-long.h" -#include "xgetcwd.h" - /* 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 some systems lack - support for fchdir, and getcwd is not robust or as efficient. + 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. Some systems lack fchdir altogether: OS/2, - Cygwin (as of March 2003), SCO Xenix. At least SunOS 4 and Irix 5.3 - provide the function, yet it doesn't work for partitions on which - auditing is enabled. */ + 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 + doesn't work for partitions on which auditing is enabled. If + you're still using an obsolete system with these problems, please + send email to the maintainer of this code. */ int save_cwd (struct saved_cwd *cwd) { -#if !HAVE_FCHDIR -# undef fchdir -# define fchdir(x) (abort (), 0) - bool have_working_fchdir = false; - bool fchdir_needs_testing = false; -#elif (__sgi || __sun) - static bool have_working_fchdir = true; - bool fchdir_needs_testing = true; -#else - bool have_working_fchdir = true; - bool fchdir_needs_testing = false; -#endif - - cwd->desc = -1; cwd->name = NULL; - if (have_working_fchdir) + cwd->desc = open (".", O_SEARCH); + if (!GNULIB_FCNTL_SAFER) + cwd->desc = fd_safer (cwd->desc); + if (cwd->desc < 0) { - cwd->desc = open (".", O_RDONLY); - if (cwd->desc < 0) - { - cwd->desc = open (".", O_WRONLY); - if (cwd->desc < 0) - { - cwd->name = xgetcwd (); - return cwd->name ? 0 : -1; - } - } - - /* On SunOS 4 and IRIX 5.3, fchdir returns EINVAL when auditing - is enabled, so we have to fall back to chdir. */ - if (fchdir_needs_testing && fchdir (cwd->desc) != 0) - { - int saved_errno = errno; - close (cwd->desc); - cwd->desc = -1; - if (saved_errno != EINVAL) - { - errno = saved_errno; - return -1; - } - have_working_fchdir = false; - } + cwd->name = getcwd (NULL, 0); + return cwd->name ? 0 : -1; } - if (!have_working_fchdir) - { - cwd->name = xgetcwd (); - if (cwd->name == NULL) - return -1; - } + set_cloexec_flag (cwd->desc, true); return 0; } @@ -134,6 +95,5 @@ free_cwd (struct saved_cwd *cwd) { if (cwd->desc >= 0) close (cwd->desc); - if (cwd->name) - free (cwd->name); + free (cwd->name); }