from Roland

src/chroot.c

@@ -0,0 +1,89 @@
+/* chroot -- run command or shell with special root directory
+   Copyright (C) 1995 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.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   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., 675 Mass Ave, Cambridge, MA 02139, USA.  */
+
+#include <config.h>
+#include <stdio.h>
+
+#include "system.h"
+#include "long-options.h"
+#include "version.h"
+
+void error ();
+
+static void usage ();
+
+/* The name this program was run with, for error messages. */
+char *program_name;
+
+int
+main (argc, argv)
+     int argc;
+     char **argv;
+{
+  int c;
+
+  program_name = argv[0];
+
+  parse_long_options (argc, argv, "chroot", version_string, usage);
+
+  if (argc == 1)
+    usage (1);
+
+  if (chroot (argv[1]))
+    error (1, errno, "cannot change root directory to %s", argv[1]);
+
+  if (argc == 2)
+    {
+      /* No command.  Run an interactive shell.  */
+      char *shell = getenv ("SHELL");
+      if (shell == NULL)
+	shell = "/bin/sh";
+      argv[0] = shell;
+      argv[1] = "-i";
+    }
+  else
+    /* The following arguments give the command.  */
+    argv += 2;
+
+  /* Execute the given command.  */
+  execvp (argv[0], argv);
+  error (1, errno, "cannot execute %s", argv[0]);
+
+  exit (1);
+  return 1;
+}
+
+static void
+usage (status)
+     int status;
+{
+  if (status != 0)
+    fprintf (stderr, "Try `%s --help' for more information.\n",
+	     program_name);
+  else
+    {
+      printf ("Usage: %s [OPTION] NEWROOT [COMMAND...]\n", program_name);
+      printf ("\
+\n\
+      --help       display this help and exit\n\
+      --version    output version information and exit\n\
+\n\
+If no command is given, runs ``${SHELL} -i'' (default: /bin/sh).\n\
+");
+    }
+  exit (status);
+}