swaponoff: add support for -e

[oweals/busybox.git] / miscutils / eject.c

diff --git a/miscutils/eject.c b/miscutils/eject.c
index 2643f36d571c2ac783575478d2379ae900c11c60..a20e04b7f45fbdbb1a70739f1535532a3e673e41 100644 (file)
--- a/miscutils/eject.c
+++ b/miscutils/eject.c
@@ -1,11 +1,11 @@
+/* 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.
- *
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
  */
 
 /*
@@ -13,37 +13,116 @@
  * Most of the dirty work blatantly ripped off from cat.c =)
  */
 
-#include <fcntl.h>
-#include <sys/ioctl.h>
-#include <unistd.h>
+//usage:#define eject_trivial_usage
+//usage:       "[-t] [-T] [DEVICE]"
+//usage:#define eject_full_usage "\n\n"
+//usage:       "Eject DEVICE or default /dev/cdrom\n"
+//usage:       IF_FEATURE_EJECT_SCSI(
+//usage:     "\n       -s      SCSI device"
+//usage:       )
+//usage:     "\n       -t      Close tray"
+//usage:     "\n       -T      Open/close tray (toggle)"
+
 #include <sys/mount.h>
-#include <mntent.h>
-#include "busybox.h"
+#include "libbb.h"
+/* Must be after libbb.h: they need size_t */
+#include "fix_u32.h"
+#include <scsi/sg.h>
+#include <scsi/scsi.h>
 
 /* various defines swiped from linux/cdrom.h */
 #define CDROMCLOSETRAY            0x5319  /* pendant of CDROMEJECT  */
 #define CDROMEJECT                0x5309  /* Ejects the cdrom media */
-#define DEFAULT_CDROM             "/dev/cdrom"
+#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) */
 
-extern int eject_main(int argc, char **argv)
+static void eject_scsi(const char *dev)
 {
-       unsigned long flags;
-       char *device;
-       struct mntent *m;
-
-       flags = bb_getopt_ulflags(argc, argv, "t");
-       device = argv[optind] ? : DEFAULT_CDROM;
-
-       if ((m = find_mount_point(device, bb_path_mtab_file))) {
-               if (umount(m->mnt_dir)) {
-                       bb_error_msg_and_die("Can't umount");
-               } else if (ENABLE_FEATURE_MTAB_SUPPORT) {
-                       erase_mtab(m->mnt_fsname);
-               }
+       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);
        }
-       if (ioctl(bb_xopen(device, (O_RDONLY | O_NONBLOCK)),
-                               (flags ? CDROMCLOSETRAY : CDROMEJECT))) {
-               bb_perror_msg_and_die(device);
+
+       /* 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;
        }
-       return (EXIT_SUCCESS);
+
+       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" IF_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_nonblocking(device), 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;
 }