LXR busybox/util-linux/fdformat.c

   1/* vi: set sw=4 ts=4: */
   2/*
   3 * fdformat.c  -  Low-level formats a floppy disk - Werner Almesberger
   4 * 5 July 2003 -- modified for Busybox by Erik Andersen
   5 *
   6 * Licensed under GPLv2, see file LICENSE in this source tree.
   7 */
   8//config:config FDFORMAT
   9//config:       bool "fdformat (4.4 kb)"
  10//config:       default y
  11//config:       select PLATFORM_LINUX
  12//config:       help
  13//config:       fdformat is used to low-level format a floppy disk.
  14
  15//applet:IF_FDFORMAT(APPLET(fdformat, BB_DIR_USR_SBIN, BB_SUID_DROP))
  16
  17//kbuild:lib-$(CONFIG_FDFORMAT) += fdformat.o
  18
  19//usage:#define fdformat_trivial_usage
  20//usage:       "[-n] DEVICE"
  21//usage:#define fdformat_full_usage "\n\n"
  22//usage:       "Format floppy disk\n"
  23//usage:     "\n        -n      Don't verify after format"
  24
  25#include "libbb.h"
  26
  27
  28/* Stuff extracted from linux/fd.h */
  29struct floppy_struct {
  30        unsigned int    size,           /* nr of sectors total */
  31                        sect,           /* sectors per track */
  32                        head,           /* nr of heads */
  33                        track,          /* nr of tracks */
  34                        stretch;        /* !=0 means double track steps */
  35#define FD_STRETCH 1
  36#define FD_SWAPSIDES 2
  37
  38        unsigned char   gap,            /* gap1 size */
  39
  40                        rate,           /* data rate. |= 0x40 for perpendicular */
  41#define FD_2M 0x4
  42#define FD_SIZECODEMASK 0x38
  43#define FD_SIZECODE(floppy) (((((floppy)->rate&FD_SIZECODEMASK)>> 3)+ 2) %8)
  44#define FD_SECTSIZE(floppy) ( (floppy)->rate & FD_2M ? \
  45                             512 : 128 << FD_SIZECODE(floppy) )
  46#define FD_PERP 0x40
  47
  48                        spec1,          /* stepping rate, head unload time */
  49                        fmt_gap;        /* gap2 size */
  50        const char      * name; /* used only for predefined formats */
  51};
  52struct format_descr {
  53        unsigned int device,head,track;
  54};
  55#define FDFMTBEG _IO(2,0x47)
  56#define FDFMTTRK _IOW(2,0x48, struct format_descr)
  57#define FDFMTEND _IO(2,0x49)
  58#define FDGETPRM _IOR(2, 0x04, struct floppy_struct)
  59#define FD_FILL_BYTE 0xF6 /* format fill byte. */
  60
  61int fdformat_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
  62int fdformat_main(int argc UNUSED_PARAM, char **argv)
  63{
  64        int fd, n, cyl, read_bytes, verify;
  65        unsigned char *data;
  66        struct stat st;
  67        struct floppy_struct param;
  68        struct format_descr descr;
  69
  70        verify = !getopt32(argv, "^" "n" "\0" "=1");
  71        argv += optind;
  72
  73        xstat(*argv, &st);
  74        if (!S_ISBLK(st.st_mode)) {
  75                bb_error_msg_and_die("%s: not a block device", *argv);
  76                /* do not test major - perhaps this was an USB floppy */
  77        }
  78
  79        /* O_RDWR for formatting and verifying */
  80        fd = xopen(*argv, O_RDWR);
  81
  82        /* original message was: "Could not determine current format type" */
  83        xioctl(fd, FDGETPRM, &param);
  84
  85        printf("%s-sided, %u tracks, %u sec/track. Total capacity %d kB\n",
  86                (param.head == 2) ? "Double" : "Single",
  87                param.track, param.sect, param.size >> 1);
  88
  89        /* FORMAT */
  90        printf("Formatting... ");
  91        xioctl(fd, FDFMTBEG, NULL);
  92
  93        /* n == track */
  94        for (n = 0; n < param.track; n++) {
  95                descr.head = 0;
  96                descr.track = n;
  97                xioctl(fd, FDFMTTRK, &descr);
  98                printf("%3d\b\b\b", n);
  99                if (param.head == 2) {
 100                        descr.head = 1;
 101                        xioctl(fd, FDFMTTRK, &descr);
 102                }
 103        }
 104
 105        xioctl(fd, FDFMTEND, NULL);
 106        puts("Done");
 107
 108        /* VERIFY */
 109        if (verify) {
 110                /* n == cyl_size */
 111                n = param.sect*param.head*512;
 112
 113                data = xmalloc(n);
 114                printf("Verifying... ");
 115                for (cyl = 0; cyl < param.track; cyl++) {
 116                        printf("%3d\b\b\b", cyl);
 117                        read_bytes = safe_read(fd, data, n);
 118                        if (read_bytes != n) {
 119                                if (read_bytes < 0) {
 120                                        bb_perror_msg(bb_msg_read_error);
 121                                }
 122                                bb_error_msg_and_die("problem reading cylinder %d, "
 123                                        "expected %d, read %d", cyl, n, read_bytes);
 124                                // FIXME: maybe better seek & continue??
 125                        }
 126                        /* Check backwards so we don't need a counter */
 127                        while (--read_bytes >= 0) {
 128                                if (data[read_bytes] != FD_FILL_BYTE) {
 129                                        printf("bad data in cyl %d\nContinuing... ", cyl);
 130                                }
 131                        }
 132                }
 133                /* There is no point in freeing blocks at the end of a program, because
 134                all of the program's space is given back to the system when the process
 135                terminates.*/
 136
 137                if (ENABLE_FEATURE_CLEAN_UP) free(data);
 138
 139                puts("Done");
 140        }
 141
 142        if (ENABLE_FEATURE_CLEAN_UP) close(fd);
 143
 144        /* Don't bother closing.  Exit does
 145         * that, so we can save a few bytes */
 146        return EXIT_SUCCESS;
 147}
 148