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