eject.c 3.5 KB

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  1. /* vi: set sw=4 ts=4: */
  2. /*
  3. * eject implementation for busybox
  4. *
  5. * Copyright (C) 2004 Peter Willis <psyphreak@phreaker.net>
  6. * Copyright (C) 2005 Tito Ragusa <farmatito@tiscali.it>
  7. *
  8. * Licensed under GPLv2 or later, see file LICENSE in this source tree.
  9. */
  10. /*
  11. * This is a simple hack of eject based on something Erik posted in #uclibc.
  12. * Most of the dirty work blatantly ripped off from cat.c =)
  13. */
  14. //usage:#define eject_trivial_usage
  15. //usage: "[-t] [-T] [DEVICE]"
  16. //usage:#define eject_full_usage "\n\n"
  17. //usage: "Eject DEVICE or default /dev/cdrom\n"
  18. //usage: IF_FEATURE_EJECT_SCSI(
  19. //usage: "\n -s SCSI device"
  20. //usage: )
  21. //usage: "\n -t Close tray"
  22. //usage: "\n -T Open/close tray (toggle)"
  23. #include <sys/mount.h>
  24. #include "libbb.h"
  25. #if ENABLE_FEATURE_EJECT_SCSI
  26. /* Must be after libbb.h: they need size_t */
  27. # include "fix_u32.h"
  28. # include <scsi/sg.h>
  29. # include <scsi/scsi.h>
  30. #endif
  31. #define dev_fd 3
  32. /* Code taken from the original eject (http://eject.sourceforge.net/),
  33. * refactored it a bit for busybox (ne-bb@nicoerfurth.de) */
  34. #if ENABLE_FEATURE_EJECT_SCSI
  35. static void eject_scsi(const char *dev)
  36. {
  37. static const char sg_commands[3][6] = {
  38. { ALLOW_MEDIUM_REMOVAL, 0, 0, 0, 0, 0 },
  39. { START_STOP, 0, 0, 0, 1, 0 },
  40. { START_STOP, 0, 0, 0, 2, 0 }
  41. };
  42. unsigned i;
  43. unsigned char sense_buffer[32];
  44. unsigned char inqBuff[2];
  45. sg_io_hdr_t io_hdr;
  46. if ((ioctl(dev_fd, SG_GET_VERSION_NUM, &i) < 0) || (i < 30000))
  47. bb_error_msg_and_die("not a sg device or old sg driver");
  48. memset(&io_hdr, 0, sizeof(sg_io_hdr_t));
  49. io_hdr.interface_id = 'S';
  50. io_hdr.cmd_len = 6;
  51. io_hdr.mx_sb_len = sizeof(sense_buffer);
  52. io_hdr.dxfer_direction = SG_DXFER_NONE;
  53. /* io_hdr.dxfer_len = 0; */
  54. io_hdr.dxferp = inqBuff;
  55. io_hdr.sbp = sense_buffer;
  56. io_hdr.timeout = 2000;
  57. for (i = 0; i < 3; i++) {
  58. io_hdr.cmdp = (void *)sg_commands[i];
  59. ioctl_or_perror_and_die(dev_fd, SG_IO, (void *)&io_hdr, "%s", dev);
  60. }
  61. /* force kernel to reread partition table when new disc is inserted */
  62. ioctl(dev_fd, BLKRRPART);
  63. }
  64. #else
  65. # define eject_scsi(dev) ((void)0)
  66. #endif
  67. /* various defines swiped from linux/cdrom.h */
  68. #define CDROMCLOSETRAY 0x5319 /* pendant of CDROMEJECT */
  69. #define CDROMEJECT 0x5309 /* Ejects the cdrom media */
  70. #define CDROM_DRIVE_STATUS 0x5326 /* Get tray position, etc. */
  71. /* drive status possibilities returned by CDROM_DRIVE_STATUS ioctl */
  72. #define CDS_TRAY_OPEN 2
  73. #define FLAG_CLOSE 1
  74. #define FLAG_SMART 2
  75. #define FLAG_SCSI 4
  76. static void eject_cdrom(unsigned flags, const char *dev)
  77. {
  78. int cmd = CDROMEJECT;
  79. if (flags & FLAG_CLOSE
  80. || ((flags & FLAG_SMART) && ioctl(dev_fd, CDROM_DRIVE_STATUS) == CDS_TRAY_OPEN)
  81. ) {
  82. cmd = CDROMCLOSETRAY;
  83. }
  84. ioctl_or_perror_and_die(dev_fd, cmd, NULL, "%s", dev);
  85. }
  86. int eject_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
  87. int eject_main(int argc UNUSED_PARAM, char **argv)
  88. {
  89. unsigned flags;
  90. const char *device;
  91. opt_complementary = "?1:t--T:T--t";
  92. flags = getopt32(argv, "tT" IF_FEATURE_EJECT_SCSI("s"));
  93. device = argv[optind] ? argv[optind] : "/dev/cdrom";
  94. /* We used to do "umount <device>" here, but it was buggy
  95. if something was mounted OVER cdrom and
  96. if cdrom is mounted many times.
  97. This works equally well (or better):
  98. #!/bin/sh
  99. umount /dev/cdrom
  100. eject /dev/cdrom
  101. */
  102. xmove_fd(xopen_nonblocking(device), dev_fd);
  103. if (ENABLE_FEATURE_EJECT_SCSI && (flags & FLAG_SCSI))
  104. eject_scsi(device);
  105. else
  106. eject_cdrom(flags, device);
  107. if (ENABLE_FEATURE_CLEAN_UP)
  108. close(dev_fd);
  109. return EXIT_SUCCESS;
  110. }