busybox/miscutils/eject.c
2008-07-05 09:18:54 +00:00

117 lines
3.0 KiB
C

/* vi: set sw=4 ts=4: */
/*
* eject implementation for busybox
*
* Copyright (C) 2004 Peter Willis <psyphreak@phreaker.net>
* Copyright (C) 2005 Tito Ragusa <farmatito@tiscali.it>
*
* Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
*/
/*
* This is a simple hack of eject based on something Erik posted in #uclibc.
* Most of the dirty work blatantly ripped off from cat.c =)
*/
#include "libbb.h"
/* various defines swiped from linux/cdrom.h */
#define CDROMCLOSETRAY 0x5319 /* pendant of CDROMEJECT */
#define CDROMEJECT 0x5309 /* Ejects the cdrom media */
#define CDROM_DRIVE_STATUS 0x5326 /* Get tray position, etc. */
/* drive status possibilities returned by CDROM_DRIVE_STATUS ioctl */
#define CDS_TRAY_OPEN 2
#define dev_fd 3
/* Code taken from the original eject (http://eject.sourceforge.net/),
* refactored it a bit for busybox (ne-bb@nicoerfurth.de) */
#include <scsi/sg.h>
#include <scsi/scsi.h>
static void eject_scsi(const char *dev)
{
static const char sg_commands[3][6] = {
{ ALLOW_MEDIUM_REMOVAL, 0, 0, 0, 0, 0 },
{ START_STOP, 0, 0, 0, 1, 0 },
{ START_STOP, 0, 0, 0, 2, 0 }
};
unsigned i;
unsigned char sense_buffer[32];
unsigned char inqBuff[2];
sg_io_hdr_t io_hdr;
if ((ioctl(dev_fd, SG_GET_VERSION_NUM, &i) < 0) || (i < 30000))
bb_error_msg_and_die("not a sg device or old sg driver");
memset(&io_hdr, 0, sizeof(sg_io_hdr_t));
io_hdr.interface_id = 'S';
io_hdr.cmd_len = 6;
io_hdr.mx_sb_len = sizeof(sense_buffer);
io_hdr.dxfer_direction = SG_DXFER_NONE;
/* io_hdr.dxfer_len = 0; */
io_hdr.dxferp = inqBuff;
io_hdr.sbp = sense_buffer;
io_hdr.timeout = 2000;
for (i = 0; i < 3; i++) {
io_hdr.cmdp = (void *)sg_commands[i];
ioctl_or_perror_and_die(dev_fd, SG_IO, (void *)&io_hdr, "%s", dev);
}
/* force kernel to reread partition table when new disc is inserted */
ioctl(dev_fd, BLKRRPART);
}
#define FLAG_CLOSE 1
#define FLAG_SMART 2
#define FLAG_SCSI 4
static void eject_cdrom(unsigned flags, const char *dev)
{
int cmd = CDROMEJECT;
if (flags & FLAG_CLOSE
|| (flags & FLAG_SMART && ioctl(dev_fd, CDROM_DRIVE_STATUS) == CDS_TRAY_OPEN)
) {
cmd = CDROMCLOSETRAY;
}
ioctl_or_perror_and_die(dev_fd, cmd, NULL, "%s", dev);
}
int eject_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int eject_main(int argc UNUSED_PARAM, char **argv)
{
unsigned flags;
const char *device;
opt_complementary = "?1:t--T:T--t";
flags = getopt32(argv, "tT" USE_FEATURE_EJECT_SCSI("s"));
device = argv[optind] ? argv[optind] : "/dev/cdrom";
/* We used to do "umount <device>" here, but it was buggy
if something was mounted OVER cdrom and
if cdrom is mounted many times.
This works equally well (or better):
#!/bin/sh
umount /dev/cdrom
eject /dev/cdrom
*/
xmove_fd(xopen(device, O_RDONLY|O_NONBLOCK), dev_fd);
if (ENABLE_FEATURE_EJECT_SCSI && (flags & FLAG_SCSI))
eject_scsi(device);
else
eject_cdrom(flags, device);
if (ENABLE_FEATURE_CLEAN_UP)
close(dev_fd);
return EXIT_SUCCESS;
}