busybox/pivot_root.c

57 lines
1.3 KiB
C
Raw Normal View History

/* vi: set sw=4 ts=4: */
/*
* pivot_root.c - Change root file system. Based on util-linux 2.10s
*
* busyboxed by Evin Robertson
* pivot_root syscall stubbed by Erik Andersen, so it will compile
* regardless of the kernel being used.
*/
#include <stdlib.h>
#include <stdio.h>
#include <errno.h>
#include <sys/syscall.h>
#include <linux/unistd.h>
#include "busybox.h"
#ifndef __NR_pivot_root
#warning This kernel does not support the pivot_root syscall
#warning The pivot_root system call is being stubbed out...
int pivot_root(const char * new_root,const char * put_old)
{
/* BusyBox was compiled against a kernel that did not support
* the pivot_root system call. To make this application work,
* you will need to recompile with a kernel supporting the
* pivot_root system call.
*/
fprintf(stderr, "\n\nTo make this application work, you will need to recompile\n");
fprintf(stderr, "with a kernel supporting the pivot_root system call. -Erik\n\n");
errno=ENOSYS;
return -1;
}
#else
static _syscall2(int,pivot_root,const char *,new_root,const char *,put_old)
#endif
int pivot_root_main(int argc, char **argv)
{
if (argc != 3)
show_usage();
if (pivot_root(argv[1],argv[2]) < 0)
perror_msg_and_die("pivot_root");
return EXIT_SUCCESS;
}
/*
Local Variables:
c-file-style: "linux"
c-basic-offset: 4
tab-width: 4
End:
*/