release/src/router/busybox/util-linux/pivot_root.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * pivot_root.c - Change root file system.  Based on util-linux 2.10s
   4  *
   5  * busyboxed by Evin Robertson
   6  * pivot_root syscall stubbed by Erik Andersen, so it will compile
   7  *     regardless of the kernel being used.
   8  *
   9  * Licensed under GPLv2, see file LICENSE in this source tree.
  10  */
  11
  12 //usage:#define pivot_root_trivial_usage
  13 //usage:       "NEW_ROOT PUT_OLD"
  14 //usage:#define pivot_root_full_usage "\n\n"
  15 //usage:       "Move the current root file system to PUT_OLD and make NEW_ROOT\n"
  16 //usage:       "the new root file system"
  17
  18 #include "libbb.h"
  19
  20 extern int pivot_root(const char * new_root,const char * put_old);
  21
  22 int pivot_root_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
  23 int pivot_root_main(int argc, char **argv)
  24 {
  25         if (argc != 3)
  26                 bb_show_usage();
  27
  28         if (pivot_root(argv[1], argv[2]) < 0) {
  29                 /* prints "pivot_root: <strerror text>" */
  30                 bb_perror_nomsg_and_die();
  31         }
  32
  33         return EXIT_SUCCESS;
  34 }