libbb: consolidate the code to set termios unbuffered mode

[oweals/busybox.git] / util-linux / pivot_root.c

diff --git a/util-linux/pivot_root.c b/util-linux/pivot_root.c
index d7b80d7493a7d50f0c522b4de68790b2eca44ab3..9bdae506cffed8615fdaf424fe1a0379477e3492 100644 (file)
--- a/util-linux/pivot_root.c
+++ b/util-linux/pivot_root.c
@@ -3,37 +3,48 @@
  * 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.
+ *
+ * Licensed under GPLv2, see file LICENSE in this source tree.
  */
-#include <stdlib.h>
-#include <stdio.h>
-#include <sys/syscall.h>
-#include <linux/unistd.h>
-#include "busybox.h"
-
-#ifndef __NR_pivot_root
-#error Sorry, but this kernel does not support the pivot_root syscall
-#endif
-
-static _syscall2(int,pivot_root,const char *,new_root,const char *,put_old)
-
-
+//config:config PIVOT_ROOT
+//config:      bool "pivot_root"
+//config:      default y
+//config:      select PLATFORM_LINUX
+//config:      help
+//config:        The pivot_root utility swaps the mount points for the root filesystem
+//config:        with some other mounted filesystem. This allows you to do all sorts
+//config:        of wild and crazy things with your Linux system and is far more
+//config:        powerful than 'chroot'.
+//config:
+//config:        Note: This is for initrd in linux 2.4. Under initramfs (introduced
+//config:        in linux 2.6) use switch_root instead.
+
+//applet:IF_PIVOT_ROOT(APPLET(pivot_root, BB_DIR_SBIN, BB_SUID_DROP))
+
+//kbuild:lib-$(CONFIG_PIVOT_ROOT) += pivot_root.o
+
+//usage:#define pivot_root_trivial_usage
+//usage:       "NEW_ROOT PUT_OLD"
+//usage:#define pivot_root_full_usage "\n\n"
+//usage:       "Move the current root file system to PUT_OLD and make NEW_ROOT\n"
+//usage:       "the new root file system"
+
+#include "libbb.h"
+
+extern int pivot_root(const char * new_root,const char * put_old);
+
+int pivot_root_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 int pivot_root_main(int argc, char **argv)
 {
-    if (argc != 3)
-        show_usage();
+       if (argc != 3)
+               bb_show_usage();
 
-    if (pivot_root(argv[1],argv[2]) < 0)
-        perror_msg_and_die("pivot_root");
-
-    return EXIT_SUCCESS;
+       if (pivot_root(argv[1], argv[2]) < 0) {
+               /* prints "pivot_root: <strerror text>" */
+               bb_perror_nomsg_and_die();
+       }
 
+       return EXIT_SUCCESS;
 }
-
-
-/*
-Local Variables:
-c-file-style: "linux"
-c-basic-offset: 4
-tab-width: 4
-End:
-*/