src/chroot.c

   1 /* chroot -- run command or shell with special root directory
   2    Copyright (C) 95, 96, 1997, 1999, 2000 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 2, or (at your option)
   7    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, write to the Free Software Foundation,
  16    Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  17
  18 /* Written by Roland McGrath.  */
  19
  20 #include <config.h>
  21 #include <stdio.h>
  22 #include <sys/types.h>
  23
  24 #include "system.h"
  25 #include "long-options.h"
  26 #include "error.h"
  27 #include "closeout.h"
  28
  29 /* The official name of this program (e.g., no `g' prefix).  */
  30 #define PROGRAM_NAME "chroot"
  31
  32 #define AUTHORS "Roland McGrath"
  33
  34 /* The name this program was run with, for error messages. */
  35 char *program_name;
  36
  37 void
  38 usage (int status)
  39 {
  40   if (status != 0)
  41     fprintf (stderr, _("Try `%s --help' for more information.\n"),
  42              program_name);
  43   else
  44     {
  45       printf (_("\
  46 Usage: %s NEWROOT [COMMAND...]\n\
  47   or:  %s OPTION\n\
  48 "), program_name, program_name);
  49       printf (_("\
  50 Run COMMAND with root directory set to NEWROOT.\n\
  51 \n\
  52       --help       display this help and exit\n\
  53       --version    output version information and exit\n\
  54 \n\
  55 If no command is given, run ``${SHELL} -i'' (default: /bin/sh).\n\
  56 "));
  57       puts (_("\nReport bugs to <bug-sh-utils@gnu.org>."));
  58     }
  59   exit (status);
  60 }
  61
  62 int
  63 main (int argc, char **argv)
  64 {
  65   program_name = argv[0];
  66   setlocale (LC_ALL, "");
  67   bindtextdomain (PACKAGE, LOCALEDIR);
  68   textdomain (PACKAGE);
  69
  70   atexit (close_stdout);
  71
  72   parse_long_options (argc, argv, PROGRAM_NAME, GNU_PACKAGE, VERSION,
  73                       AUTHORS, usage);
  74   if (argc == 1)
  75     {
  76       error (0, 0, _("too few arguments"));
  77       usage (1);
  78     }
  79
  80   if (chroot (argv[1]))
  81     error (1, errno, _("cannot change root directory to %s"), argv[1]);
  82
  83   if (chdir ("/"))
  84     error (1, errno, _("cannot chdir to root directory"));
  85
  86   if (argc == 2)
  87     {
  88       /* No command.  Run an interactive shell.  */
  89       char *shell = getenv ("SHELL");
  90       if (shell == NULL)
  91         shell = "/bin/sh";
  92       argv[0] = shell;
  93       argv[1] = "-i";
  94     }
  95   else
  96     {
  97       /* The following arguments give the command.  */
  98       argv += 2;
  99     }
 100
 101   /* Execute the given command.  */
 102   execvp (argv[0], argv);
 103   error (1, errno, _("cannot execute %s"), argv[0]);
 104
 105   exit (1);
 106   return 1;
 107 }