1 /* vi: set sw=4 ts=4: */
3 * fdformat.c - Low-level formats a floppy disk - Werner Almesberger
4 * 5 July 2003 -- modified for Busybox by Erik Andersen
6 * Licensed under GPLv2, see file LICENSE in this source tree.
8 //config:config FDFORMAT
9 //config: bool "fdformat (4.4 kb)"
11 //config: select PLATFORM_LINUX
13 //config: fdformat is used to low-level format a floppy disk.
15 //applet:IF_FDFORMAT(APPLET(fdformat, BB_DIR_USR_SBIN, BB_SUID_DROP))
17 //kbuild:lib-$(CONFIG_FDFORMAT) += fdformat.o
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"
28 /* Stuff extracted from linux/fd.h */
29 struct 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 */
36 #define FD_SWAPSIDES 2
38 unsigned char gap, /* gap1 size */
40 rate, /* data rate. |= 0x40 for perpendicular */
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) )
48 spec1, /* stepping rate, head unload time */
49 fmt_gap; /* gap2 size */
50 const char * name; /* used only for predefined formats */
53 unsigned int device,head,track;
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. */
61 int fdformat_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
62 int fdformat_main(int argc UNUSED_PARAM, char **argv)
64 int fd, n, cyl, read_bytes, verify;
67 struct floppy_struct param;
68 struct format_descr descr;
70 verify = !getopt32(argv, "^" "n" "\0" "=1");
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 */
79 /* O_RDWR for formatting and verifying */
80 fd = xopen(*argv, O_RDWR);
82 /* original message was: "Could not determine current format type" */
83 xioctl(fd, FDGETPRM, ¶m);
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);
90 printf("Formatting... ");
91 xioctl(fd, FDFMTBEG, NULL);
94 for (n = 0; n < param.track; n++) {
97 xioctl(fd, FDFMTTRK, &descr);
98 printf("%3d\b\b\b", n);
99 if (param.head == 2) {
101 xioctl(fd, FDFMTTRK, &descr);
105 xioctl(fd, FDFMTEND, NULL);
111 n = param.sect*param.head*512;
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_simple_perror_msg(bb_msg_read_error);
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??
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);
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
137 if (ENABLE_FEATURE_CLEAN_UP) free(data);
142 if (ENABLE_FEATURE_CLEAN_UP) close(fd);
144 /* Don't bother closing. Exit does
145 * that, so we can save a few bytes */