81 lines
2.9 KiB
C
81 lines
2.9 KiB
C
/* vi: set sw=4 ts=4: */
|
|
/*
|
|
* freeramdisk and fdflush implementations for busybox
|
|
*
|
|
* Copyright (C) 2000 and written by Emanuele Caratti <wiz@iol.it>
|
|
* Adjusted a bit by Erik Andersen <andersen@codepoet.org>
|
|
* Unified with fdflush by Tito Ragusa <farmatito@tiscali.it>
|
|
*
|
|
* Licensed under GPLv2, see file LICENSE in this source tree.
|
|
*/
|
|
//config:config FDFLUSH
|
|
//config: bool "fdflush (1.4 kb)"
|
|
//config: default y
|
|
//config: select PLATFORM_LINUX
|
|
//config: help
|
|
//config: fdflush is only needed when changing media on slightly-broken
|
|
//config: removable media drives. It is used to make Linux believe that a
|
|
//config: hardware disk-change switch has been actuated, which causes Linux to
|
|
//config: forget anything it has cached from the previous media. If you have
|
|
//config: such a slightly-broken drive, you will need to run fdflush every time
|
|
//config: you change a disk. Most people have working hardware and can safely
|
|
//config: leave this disabled.
|
|
//config:
|
|
//config:config FREERAMDISK
|
|
//config: bool "freeramdisk (1.4 kb)"
|
|
//config: default y
|
|
//config: select PLATFORM_LINUX
|
|
//config: help
|
|
//config: Linux allows you to create ramdisks. This utility allows you to
|
|
//config: delete them and completely free all memory that was used for the
|
|
//config: ramdisk. For example, if you boot Linux into a ramdisk and later
|
|
//config: pivot_root, you may want to free the memory that is allocated to the
|
|
//config: ramdisk. If you have no use for freeing memory from a ramdisk, leave
|
|
//config: this disabled.
|
|
|
|
// APPLET_ODDNAME:name main location suid_type help
|
|
//applet:IF_FDFLUSH( APPLET_ODDNAME(fdflush, freeramdisk, BB_DIR_BIN, BB_SUID_DROP, fdflush ))
|
|
//applet:IF_FREERAMDISK(APPLET_NOEXEC(freeramdisk, freeramdisk, BB_DIR_SBIN, BB_SUID_DROP, freeramdisk))
|
|
|
|
//kbuild:lib-$(CONFIG_FDFLUSH) += freeramdisk.o
|
|
//kbuild:lib-$(CONFIG_FREERAMDISK) += freeramdisk.o
|
|
|
|
//usage:#define freeramdisk_trivial_usage
|
|
//usage: "DEVICE"
|
|
//usage:#define freeramdisk_full_usage "\n\n"
|
|
//usage: "Free all memory used by the specified ramdisk"
|
|
//usage:
|
|
//usage:#define freeramdisk_example_usage
|
|
//usage: "$ freeramdisk /dev/ram2\n"
|
|
//usage:
|
|
//usage:#define fdflush_trivial_usage
|
|
//usage: "DEVICE"
|
|
//usage:#define fdflush_full_usage "\n\n"
|
|
//usage: "Force floppy disk drive to detect disk change"
|
|
|
|
#include <sys/mount.h>
|
|
#include "libbb.h"
|
|
|
|
/* From <linux/fd.h> */
|
|
#define FDFLUSH _IO(2,0x4b)
|
|
|
|
int freeramdisk_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
|
|
int freeramdisk_main(int argc UNUSED_PARAM, char **argv)
|
|
{
|
|
int fd;
|
|
|
|
fd = xopen(single_argv(argv), O_RDWR);
|
|
|
|
// Act like freeramdisk, fdflush, or both depending on configuration.
|
|
ioctl_or_perror_and_die(fd,
|
|
((ENABLE_FREERAMDISK && applet_name[1] == 'r') || !ENABLE_FDFLUSH)
|
|
? BLKFLSBUF
|
|
: FDFLUSH,
|
|
NULL, "%s", argv[1]
|
|
);
|
|
|
|
if (ENABLE_FEATURE_CLEAN_UP) close(fd);
|
|
|
|
return EXIT_SUCCESS;
|
|
}
|