lib/dircallback.c

   1 /* listfile.c -- run a function in a specific directory
   2    Copyright (C) 2007, 2008 Free Software Foundation, Inc.
   3
   4    This program is free software: you can redistribute it and/or modify
   5    it under the terms of the GNU General Public License as published by
   6    the Free Software Foundation, either version 3 of the License, or
   7    (at your option) any later version.
   8
   9    This program is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12    GNU General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License
  15    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16 */
  17
  18 /* This file was written by James Youngman, based on gnulib'c at-func.c.
  19  */
  20
  21
  22 #include <config.h>
  23
  24
  25 #include "openat.h"
  26 #include <stdarg.h>
  27 #include <stddef.h>
  28 #include <errno.h>
  29
  30 #include "fcntl--.h"
  31 #include "lstat.h"
  32 #include "save-cwd.h"
  33
  34
  35 /* The presence of unistd.h is assumed by gnulib these days, so we
  36  * might as well assume it too.
  37  */
  38 #include <unistd.h> /* for readlink() */
  39
  40 #ifdef HAVE_LOCALE_H
  41 #include <locale.h>
  42 #endif
  43
  44 #if ENABLE_NLS
  45 # include <libintl.h>
  46 # define _(Text) gettext (Text)
  47 #else
  48 # define _(Text) Text
  49 #define textdomain(Domain)
  50 #define bindtextdomain(Package, Directory)
  51 #endif
  52 #ifdef gettext_noop
  53 # define N_(String) gettext_noop (String)
  54 #else
  55 /* See locate.c for explanation as to why not use (String) */
  56 # define N_(String) String
  57 #endif
  58
  59
  60
  61 int
  62 run_in_dir (int dir_fd, int (*callback)(void*), void *usercontext)
  63 {
  64   if (dir_fd == AT_FDCWD)
  65     {
  66       return (*callback)(usercontext);
  67     }
  68   else
  69     {
  70       struct saved_cwd saved_cwd;
  71       int saved_errno;
  72       int err;
  73
  74       if (save_cwd (&saved_cwd) != 0)
  75         openat_save_fail (errno);
  76
  77       if (fchdir (dir_fd) != 0)
  78         {
  79           saved_errno = errno;
  80           free_cwd (&saved_cwd);
  81           errno = saved_errno;
  82       return -1;
  83         }
  84
  85       err = (*callback)(usercontext);
  86       saved_errno = (err < 0 ? errno : 0);
  87
  88       if (restore_cwd (&saved_cwd) != 0)
  89         openat_restore_fail (errno);
  90
  91       free_cwd (&saved_cwd);
  92
  93       if (saved_errno)
  94         errno = saved_errno;
  95       return err;
  96     }
  97 }