util-linux/fdformat.c

   1 /* vi: set sw=4 ts=4: */
   2 /* fdformat.c  -  Low-level formats a floppy disk - Werner Almesberger */
   3
   4 /* 5 July 2003 -- modified for Busybox by Erik Andersen
   5  */
   6
   7 #include "libbb.h"
   8
   9
  10 /* Stuff extracted from linux/fd.h */
  11 struct floppy_struct {
  12         unsigned int    size,           /* nr of sectors total */
  13                         sect,           /* sectors per track */
  14                         head,           /* nr of heads */
  15                         track,          /* nr of tracks */
  16                         stretch;        /* !=0 means double track steps */
  17 #define FD_STRETCH 1
  18 #define FD_SWAPSIDES 2
  19
  20         unsigned char   gap,            /* gap1 size */
  21
  22                         rate,           /* data rate. |= 0x40 for perpendicular */
  23 #define FD_2M 0x4
  24 #define FD_SIZECODEMASK 0x38
  25 #define FD_SIZECODE(floppy) (((((floppy)->rate&FD_SIZECODEMASK)>> 3)+ 2) %8)
  26 #define FD_SECTSIZE(floppy) ( (floppy)->rate & FD_2M ? \
  27                              512 : 128 << FD_SIZECODE(floppy) )
  28 #define FD_PERP 0x40
  29
  30                         spec1,          /* stepping rate, head unload time */
  31                         fmt_gap;        /* gap2 size */
  32         const char      * name; /* used only for predefined formats */
  33 };
  34 struct format_descr {
  35         unsigned int device,head,track;
  36 };
  37 #define FDFMTBEG _IO(2,0x47)
  38 #define FDFMTTRK _IOW(2,0x48, struct format_descr)
  39 #define FDFMTEND _IO(2,0x49)
  40 #define FDGETPRM _IOR(2, 0x04, struct floppy_struct)
  41 #define FD_FILL_BYTE 0xF6 /* format fill byte. */
  42
  43 int fdformat_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
  44 int fdformat_main(int argc, char **argv)
  45 {
  46         int fd, n, cyl, read_bytes, verify;
  47         unsigned char *data;
  48         struct stat st;
  49         struct floppy_struct param;
  50         struct format_descr descr;
  51
  52         if (argc < 2) {
  53                 bb_show_usage();
  54         }
  55         verify = !getopt32(argv, "n");
  56         argv += optind;
  57
  58         xstat(*argv, &st);
  59         if (!S_ISBLK(st.st_mode)) {
  60                 bb_error_msg_and_die("%s: not a block device", *argv);
  61                 /* do not test major - perhaps this was an USB floppy */
  62         }
  63
  64         /* O_RDWR for formatting and verifying */
  65         fd = xopen(*argv, O_RDWR);
  66
  67         /* original message was: "Could not determine current format type" */
  68         xioctl(fd, FDGETPRM, &param);
  69
  70         printf("%s-sided, %d tracks, %d sec/track. Total capacity %d kB\n",
  71                 (param.head == 2) ? "Double" : "Single",
  72                 param.track, param.sect, param.size >> 1);
  73
  74         /* FORMAT */
  75         printf("Formatting... ");
  76         xioctl(fd, FDFMTBEG, NULL);
  77
  78         /* n == track */
  79         for (n = 0; n < param.track; n++) {
  80                 descr.head = 0;
  81                 descr.track = n;
  82                 xioctl(fd, FDFMTTRK, &descr);
  83                 printf("%3d\b\b\b", n);
  84                 if (param.head == 2) {
  85                         descr.head = 1;
  86                         xioctl(fd, FDFMTTRK, &descr);
  87                 }
  88         }
  89
  90         xioctl(fd, FDFMTEND, NULL);
  91         printf("done\n");
  92
  93         /* VERIFY */
  94         if (verify) {
  95                 /* n == cyl_size */
  96                 n = param.sect*param.head*512;
  97
  98                 data = xmalloc(n);
  99                 printf("Verifying... ");
 100                 for (cyl = 0; cyl < param.track; cyl++) {
 101                         printf("%3d\b\b\b", cyl);
 102                         read_bytes = safe_read(fd, data, n);
 103                         if (read_bytes != n) {
 104                                 if (read_bytes < 0) {
 105                                         bb_perror_msg(bb_msg_read_error);
 106                                 }
 107                                 bb_error_msg_and_die("problem reading cylinder %d, "
 108                                         "expected %d, read %d", cyl, n, read_bytes);
 109                                 // FIXME: maybe better seek & continue??
 110                         }
 111                         /* Check backwards so we don't need a counter */
 112                         while (--read_bytes >= 0) {
 113                                 if (data[read_bytes] != FD_FILL_BYTE) {
 114                                          printf("bad data in cyl %d\nContinuing... ", cyl);
 115                                 }
 116                         }
 117                 }
 118                 /* There is no point in freeing blocks at the end of a program, because
 119                 all of the program's space is given back to the system when the process
 120                 terminates.*/
 121
 122                 if (ENABLE_FEATURE_CLEAN_UP) free(data);
 123
 124                 printf("done\n");
 125         }
 126
 127         if (ENABLE_FEATURE_CLEAN_UP) close(fd);
 128
 129         /* Don't bother closing.  Exit does
 130          * that, so we can save a few bytes */
 131         return EXIT_SUCCESS;
 132 }