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hush/util-linux/mkfs_vfat.c
Denys Vlasenko 8878c24c7d mkfs_vfat: fix gcc-4.4 warning 
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2010-06-04 15:55:17 +02:00

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/* vi: set sw=4 ts=4: */
/*
* mkfs_vfat: utility to create FAT32 filesystem
* inspired by dosfstools
*
* Busybox'ed (2009) by Vladimir Dronnikov <dronnikov@gmail.com>
*
* Licensed under GPLv2, see file LICENSE in this tarball for details.
*/
#include "libbb.h"
#include <linux/hdreg.h> /* HDIO_GETGEO */
#include <linux/fd.h> /* FDGETPRM */
#include <sys/mount.h> /* BLKSSZGET */
#if !defined(BLKSSZGET)
# define BLKSSZGET _IO(0x12, 104)
#endif
//#include <linux/msdos_fs.h>
#define SECTOR_SIZE 512
#define SECTORS_PER_BLOCK (BLOCK_SIZE / SECTOR_SIZE)
// M$ says the high 4 bits of a FAT32 FAT entry are reserved
#define EOF_FAT32 0x0FFFFFF8
#define BAD_FAT32 0x0FFFFFF7
#define MAX_CLUST_32 0x0FFFFFF0
#define ATTR_VOLUME 8
#define NUM_FATS 2
/* FAT32 filesystem looks like this:
* sector -nn...-1: "hidden" sectors, all sectors before this partition
* (-h hidden-sectors sets it. Useful only for boot loaders,
* they need to know _disk_ offset in order to be able to correctly
* address sectors relative to start of disk)
* sector 0: boot sector
* sector 1: info sector
* sector 2: set aside for boot code which didn't fit into sector 0
* ...(zero-filled sectors)...
* sector B: backup copy of sector 0 [B set by -b backup-boot-sector]
* sector B+1: backup copy of sector 1
* sector B+2: backup copy of sector 2
* ...(zero-filled sectors)...
* sector R: FAT#1 [R set by -R reserved-sectors]
* ...(FAT#1)...
* sector R+fat_size: FAT#2
* ...(FAT#2)...
* sector R+fat_size*2: cluster #2
* ...(cluster #2)...
* sector R+fat_size*2+clust_size: cluster #3
* ...(the rest is filled by clusters till the end)...
*/
enum {
// Perhaps this should remain constant
info_sector_number = 1,
// TODO: make these cmdline options
// dont forget sanity check: backup_boot_sector + 3 <= reserved_sect
backup_boot_sector = 3,
reserved_sect = 6,
};
// how many blocks we try to read while testing
#define TEST_BUFFER_BLOCKS 16
struct msdos_dir_entry {
char name[11]; /* 000 name and extension */
uint8_t attr; /* 00b attribute bits */
uint8_t lcase; /* 00c case for base and extension */
uint8_t ctime_cs; /* 00d creation time, centiseconds (0-199) */
uint16_t ctime; /* 00e creation time */
uint16_t cdate; /* 010 creation date */
uint16_t adate; /* 012 last access date */
uint16_t starthi; /* 014 high 16 bits of cluster in FAT32 */
uint16_t time; /* 016 time */
uint16_t date; /* 018 date */
uint16_t start; /* 01a first cluster */
uint32_t size; /* 01c file size in bytes */
} PACKED;
/* Example of boot sector's beginning:
0000 eb 58 90 4d 53 57 49 4e 34 2e 31 00 02 08 26 00 |...MSWIN4.1...&.|
0010 02 00 00 00 00 f8 00 00 3f 00 ff 00 3f 00 00 00 |........?...?...|
0020 54 9b d0 00 0d 34 00 00 00 00 00 00 02 00 00 00 |T....4..........|
0030 01 00 06 00 00 00 00 00 00 00 00 00 00 00 00 00 |................|
0040 80 00 29 71 df 51 e0 4e 4f 20 4e 41 4d 45 20 20 |..)q.Q.NO NAME |
0050 20 20 46 41 54 33 32 20 20 20 33 c9 8e d1 bc f4 | FAT32 3.....|
*/
struct msdos_volume_info { /* (offsets are relative to start of boot sector) */
uint8_t drive_number; /* 040 BIOS drive number */
uint8_t reserved; /* 041 unused */
uint8_t ext_boot_sign; /* 042 0x29 if fields below exist (DOS 3.3+) */
uint32_t volume_id32; /* 043 volume ID number */
char volume_label[11];/* 047 volume label */
char fs_type[8]; /* 052 typically "FATnn" */
} PACKED; /* 05a end. Total size 26 (0x1a) bytes */
struct msdos_boot_sector {
/* We use strcpy to fill both, and gcc-4.4.x complains if they are separate */
char boot_jump_and_sys_id[3+8]; /* 000 short or near jump instruction */
/*char system_id[8];*/ /* 003 name - can be used to special case partition manager volumes */
uint16_t bytes_per_sect; /* 00b bytes per logical sector */
uint8_t sect_per_clust; /* 00d sectors/cluster */
uint16_t reserved_sect; /* 00e reserved sectors (sector offset of 1st FAT relative to volume start) */
uint8_t fats; /* 010 number of FATs */
uint16_t dir_entries; /* 011 root directory entries */
uint16_t volume_size_sect; /* 013 volume size in sectors */
uint8_t media_byte; /* 015 media code */
uint16_t sect_per_fat; /* 016 sectors/FAT */
uint16_t sect_per_track; /* 018 sectors per track */
uint16_t heads; /* 01a number of heads */
uint32_t hidden; /* 01c hidden sectors (sector offset of volume within physical disk) */
uint32_t fat32_volume_size_sect; /* 020 volume size in sectors (if volume_size_sect == 0) */
uint32_t fat32_sect_per_fat; /* 024 sectors/FAT */
uint16_t fat32_flags; /* 028 bit 8: fat mirroring, low 4: active fat */
uint8_t fat32_version[2]; /* 02a major, minor filesystem version (I see 0,0) */
uint32_t fat32_root_cluster; /* 02c first cluster in root directory */
uint16_t fat32_info_sector; /* 030 filesystem info sector (usually 1) */
uint16_t fat32_backup_boot; /* 032 backup boot sector (usually 6) */
uint32_t reserved2[3]; /* 034 unused */
struct msdos_volume_info vi; /* 040 */
char boot_code[0x200 - 0x5a - 2]; /* 05a */
#define BOOT_SIGN 0xAA55
uint16_t boot_sign; /* 1fe */
} PACKED;
#define FAT_FSINFO_SIG1 0x41615252
#define FAT_FSINFO_SIG2 0x61417272
struct fat32_fsinfo {
uint32_t signature1; /* 0x52,0x52,0x41,0x61, "RRaA" */
uint32_t reserved1[128 - 8];
uint32_t signature2; /* 0x72,0x72,0x61,0x41, "rrAa" */
uint32_t free_clusters; /* free cluster count. -1 if unknown */
uint32_t next_cluster; /* most recently allocated cluster */
uint32_t reserved2[3];
uint16_t reserved3; /* 1fc */
uint16_t boot_sign; /* 1fe */
} PACKED;
struct bug_check {
char BUG1[sizeof(struct msdos_dir_entry ) == 0x20 ? 1 : -1];
char BUG2[sizeof(struct msdos_volume_info) == 0x1a ? 1 : -1];
char BUG3[sizeof(struct msdos_boot_sector) == 0x200 ? 1 : -1];
char BUG4[sizeof(struct fat32_fsinfo ) == 0x200 ? 1 : -1];
};
static const char boot_code[] ALIGN1 =
"\x0e" /* 05a: push cs */
"\x1f" /* 05b: pop ds */
"\xbe\x77\x7c" /* write_msg: mov si, offset message_txt */
"\xac" /* 05f: lodsb */
"\x22\xc0" /* 060: and al, al */
"\x74\x0b" /* 062: jz key_press */
"\x56" /* 064: push si */
"\xb4\x0e" /* 065: mov ah, 0eh */
"\xbb\x07\x00" /* 067: mov bx, 0007h */
"\xcd\x10" /* 06a: int 10h */
"\x5e" /* 06c: pop si */
"\xeb\xf0" /* 06d: jmp write_msg */
"\x32\xe4" /* key_press: xor ah, ah */
"\xcd\x16" /* 071: int 16h */
"\xcd\x19" /* 073: int 19h */
"\xeb\xfe" /* foo: jmp foo */
/* 077: message_txt: */
"This is not a bootable disk\r\n";
#define MARK_CLUSTER(cluster, value) \
((uint32_t *)fat)[cluster] = SWAP_LE32(value)
void BUG_unsupported_field_size(void);
#define STORE_LE(field, value) \
do { \
if (sizeof(field) == 4) \
field = SWAP_LE32(value); \
else if (sizeof(field) == 2) \
field = SWAP_LE16(value); \
else if (sizeof(field) == 1) \
field = (value); \
else \
BUG_unsupported_field_size(); \
} while (0)
/* compat:
* mkdosfs 2.11 (12 Mar 2005)
* Usage: mkdosfs [-A] [-c] [-C] [-v] [-I] [-l bad-block-file]
* [-b backup-boot-sector]
* [-m boot-msg-file] [-n volume-name] [-i volume-id]
* [-s sectors-per-cluster] [-S logical-sector-size]
* [-f number-of-FATs]
* [-h hidden-sectors] [-F fat-size] [-r root-dir-entries]
* [-R reserved-sectors]
* /dev/name [blocks]
*/
int mkfs_vfat_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int mkfs_vfat_main(int argc UNUSED_PARAM, char **argv)
{
struct stat st;
const char *volume_label = "";
char *buf;
char *device_name;
uoff_t volume_size_bytes;
uoff_t volume_size_sect;
uint32_t total_clust;
uint32_t volume_id;
int dev;
unsigned bytes_per_sect;
unsigned sect_per_fat;
unsigned opts;
uint16_t sect_per_track;
uint8_t media_byte;
uint8_t sect_per_clust;
uint8_t heads;
enum {
OPT_A = 1 << 0, // [IGNORED] atari format
OPT_b = 1 << 1, // [IGNORED] location of backup boot sector
OPT_c = 1 << 2, // [IGNORED] check filesystem
OPT_C = 1 << 3, // [IGNORED] create a new file
OPT_f = 1 << 4, // [IGNORED] number of FATs
OPT_F = 1 << 5, // [IGNORED, implied 32] choose FAT size
OPT_h = 1 << 6, // [IGNORED] number of hidden sectors
OPT_I = 1 << 7, // [IGNORED] don't bark at entire disk devices
OPT_i = 1 << 8, // [IGNORED] volume ID
OPT_l = 1 << 9, // [IGNORED] bad block filename
OPT_m = 1 << 10, // [IGNORED] message file
OPT_n = 1 << 11, // volume label
OPT_r = 1 << 12, // [IGNORED] root directory entries
OPT_R = 1 << 13, // [IGNORED] number of reserved sectors
OPT_s = 1 << 14, // [IGNORED] sectors per cluster
OPT_S = 1 << 15, // [IGNORED] sector size
OPT_v = 1 << 16, // verbose
};
opt_complementary = "-1";//:b+:f+:F+:h+:r+:R+:s+:S+:vv:c--l:l--c";
opts = getopt32(argv, "Ab:cCf:F:h:Ii:l:m:n:r:R:s:S:v",
NULL, NULL, NULL, NULL, NULL,
NULL, NULL, &volume_label, NULL, NULL, NULL, NULL);
argv += optind;
// cache device name
device_name = argv[0];
// default volume ID = creation time
volume_id = time(NULL);
dev = xopen(device_name, O_RDWR);
if (fstat(dev, &st) < 0)
bb_simple_perror_msg_and_die(device_name);
//
// Get image size and sector size
//
bytes_per_sect = SECTOR_SIZE;
if (!S_ISBLK(st.st_mode)) {
if (!S_ISREG(st.st_mode)) {
if (!argv[1])
bb_error_msg_and_die("image size must be specified");
}
// not a block device, skip bad sectors check
opts &= ~OPT_c;
} else {
int min_bytes_per_sect;
#if 0
unsigned device_num;
// for true block devices we do check sanity
device_num = st.st_rdev & 0xff3f;
// do we allow to format the whole disk device?
if (!(opts & OPT_I) && (
device_num == 0x0300 || // hda, hdb
(device_num & 0xff0f) == 0x0800 || // sd
device_num == 0x0d00 || // xd
device_num == 0x1600 ) // hdc, hdd
)
bb_error_msg_and_die("will not try to make filesystem on full-disk device (use -I if wanted)");
// can't work on mounted filesystems
if (find_mount_point(device_name, 0))
bb_error_msg_and_die("can't format mounted filesystem");
#endif
// get true sector size
// (parameter must be int*, not long* or size_t*)
xioctl(dev, BLKSSZGET, &min_bytes_per_sect);
if (min_bytes_per_sect > SECTOR_SIZE) {
bytes_per_sect = min_bytes_per_sect;
bb_error_msg("for this device sector size is %u", min_bytes_per_sect);
}
}
volume_size_bytes = get_volume_size_in_bytes(dev, argv[1], 1024, /*extend:*/ 1);
volume_size_sect = volume_size_bytes / bytes_per_sect;
//
// Find out or guess media parameters
//
media_byte = 0xf8;
heads = 255;
sect_per_track = 63;
sect_per_clust = 1;
{
struct hd_geometry geometry;
// size (in sectors), sect (per track), head
struct floppy_struct param;
// N.B. whether to use HDIO_GETGEO or HDIO_REQ?
if (ioctl(dev, HDIO_GETGEO, &geometry) == 0
&& geometry.sectors
&& geometry.heads
) {
// hard drive
sect_per_track = geometry.sectors;
heads = geometry.heads;
set_cluster_size:
/* For FAT32, try to do the same as M$'s format command
* (see http://www.win.tue.nl/~aeb/linux/fs/fat/fatgen103.pdf p. 20):
* fs size <= 260M: 0.5k clusters
* fs size <= 8G: 4k clusters
* fs size <= 16G: 8k clusters
* fs size > 16G: 16k clusters
*/
sect_per_clust = 1;
if (volume_size_bytes >= 260*1024*1024) {
sect_per_clust = 8;
/* fight gcc: */
/* "error: integer overflow in expression" */
/* "error: right shift count >= width of type" */
if (sizeof(off_t) > 4) {
unsigned t = (volume_size_bytes >> 31 >> 1);
if (t >= 8/4)
sect_per_clust = 16;
if (t >= 16/4)
sect_per_clust = 32;
}
}
} else {
// floppy, loop, or regular file
int not_floppy = ioctl(dev, FDGETPRM, &param);
if (not_floppy == 0) {
// floppy disk
sect_per_track = param.sect;
heads = param.head;
volume_size_sect = param.size;
volume_size_bytes = param.size * SECTOR_SIZE;
}
// setup the media descriptor byte
switch (volume_size_sect) {
case 2*360: // 5.25", 2, 9, 40 - 360K
media_byte = 0xfd;
break;
case 2*720: // 3.5", 2, 9, 80 - 720K
case 2*1200: // 5.25", 2, 15, 80 - 1200K
media_byte = 0xf9;
break;
default: // anything else
if (not_floppy)
goto set_cluster_size;
case 2*1440: // 3.5", 2, 18, 80 - 1440K
case 2*2880: // 3.5", 2, 36, 80 - 2880K
media_byte = 0xf0;
break;
}
// not floppy, but size matches floppy exactly.
// perhaps it is a floppy image.
// we already set media_byte as if it is a floppy,
// now set sect_per_track and heads.
heads = 2;
sect_per_track = (unsigned)volume_size_sect / 160;
if (sect_per_track < 9)
sect_per_track = 9;
}
}
//
// Calculate number of clusters, sectors/cluster, sectors/FAT
// (an initial guess for sect_per_clust should already be set)
//
// "mkdosfs -v -F 32 image5k 5" is the minimum:
// 2 sectors for FATs and 2 data sectors
if ((off_t)(volume_size_sect - reserved_sect) < 4)
bb_error_msg_and_die("the image is too small for FAT32");
sect_per_fat = 1;
while (1) {
while (1) {
int spf_adj;
uoff_t tcl = (volume_size_sect - reserved_sect - NUM_FATS * sect_per_fat) / sect_per_clust;
// tcl may be > MAX_CLUST_32 here, but it may be
// because sect_per_fat is underestimated,
// and with increased sect_per_fat it still may become
// <= MAX_CLUST_32. Therefore, we do not check
// against MAX_CLUST_32, but against a bigger const:
if (tcl > 0x80ffffff)
goto next;
total_clust = tcl; // fits in uint32_t
// Every cluster needs 4 bytes in FAT. +2 entries since
// FAT has space for non-existent clusters 0 and 1.
// Let's see how many sectors that needs.
//May overflow at "*4":
//spf_adj = ((total_clust+2) * 4 + bytes_per_sect-1) / bytes_per_sect - sect_per_fat;
//Same in the more obscure, non-overflowing form:
spf_adj = ((total_clust+2) + (bytes_per_sect/4)-1) / (bytes_per_sect/4) - sect_per_fat;
#if 0
bb_error_msg("sect_per_clust:%u sect_per_fat:%u total_clust:%u",
sect_per_clust, sect_per_fat, (int)tcl);
bb_error_msg("adjust to sect_per_fat:%d", spf_adj);
#endif
if (spf_adj <= 0) {
// do not need to adjust sect_per_fat.
// so, was total_clust too big after all?
if (total_clust <= MAX_CLUST_32)
goto found_total_clust; // no
// yes, total_clust is _a bit_ too big
goto next;
}
// adjust sect_per_fat, go back and recalc total_clust
// (note: just "sect_per_fat += spf_adj" isn't ok)
sect_per_fat += ((unsigned)spf_adj / 2) | 1;
}
next:
if (sect_per_clust == 128)
bb_error_msg_and_die("can't make FAT32 with >128 sectors/cluster");
sect_per_clust *= 2;
sect_per_fat = (sect_per_fat / 2) | 1;
}
found_total_clust:
//
// Print info
//
if (opts & OPT_v) {
fprintf(stderr,
"Device '%s':\n"
"heads:%u, sectors/track:%u, bytes/sector:%u\n"
"media descriptor:%02x\n"
"total sectors:%"OFF_FMT"u, clusters:%u, sectors/cluster:%u\n"
"FATs:2, sectors/FAT:%u\n"
"volumeID:%08x, label:'%s'\n",
device_name,
heads, sect_per_track, bytes_per_sect,
(int)media_byte,
volume_size_sect, (int)total_clust, (int)sect_per_clust,
sect_per_fat,
(int)volume_id, volume_label
);
}
//
// Write filesystem image sequentially (no seeking)
//
{
// (a | b) is poor man's max(a, b)
unsigned bufsize = reserved_sect;
//bufsize |= sect_per_fat; // can be quite large
bufsize |= 2; // use this instead
bufsize |= sect_per_clust;
buf = xzalloc(bufsize * bytes_per_sect);
}
{ // boot and fsinfo sectors, and their copies
struct msdos_boot_sector *boot_blk = (void*)buf;
struct fat32_fsinfo *info = (void*)(buf + bytes_per_sect);
strcpy(boot_blk->boot_jump_and_sys_id, "\xeb\x58\x90" "mkdosfs");
STORE_LE(boot_blk->bytes_per_sect, bytes_per_sect);
STORE_LE(boot_blk->sect_per_clust, sect_per_clust);
// cast in needed on big endian to suppress a warning
STORE_LE(boot_blk->reserved_sect, (uint16_t)reserved_sect);
STORE_LE(boot_blk->fats, 2);
//STORE_LE(boot_blk->dir_entries, 0); // for FAT32, stays 0
if (volume_size_sect <= 0xffff)
STORE_LE(boot_blk->volume_size_sect, volume_size_sect);
STORE_LE(boot_blk->media_byte, media_byte);
// wrong: this would make Linux think that it's fat12/16:
//if (sect_per_fat <= 0xffff)
// STORE_LE(boot_blk->sect_per_fat, sect_per_fat);
// works:
//STORE_LE(boot_blk->sect_per_fat, 0);
STORE_LE(boot_blk->sect_per_track, sect_per_track);
STORE_LE(boot_blk->heads, heads);
//STORE_LE(boot_blk->hidden, 0);
STORE_LE(boot_blk->fat32_volume_size_sect, volume_size_sect);
STORE_LE(boot_blk->fat32_sect_per_fat, sect_per_fat);
//STORE_LE(boot_blk->fat32_flags, 0);
//STORE_LE(boot_blk->fat32_version[2], 0,0);
STORE_LE(boot_blk->fat32_root_cluster, 2);
STORE_LE(boot_blk->fat32_info_sector, info_sector_number);
STORE_LE(boot_blk->fat32_backup_boot, backup_boot_sector);
//STORE_LE(boot_blk->reserved2[3], 0,0,0);
STORE_LE(boot_blk->vi.ext_boot_sign, 0x29);
STORE_LE(boot_blk->vi.volume_id32, volume_id);
strncpy(boot_blk->vi.fs_type, "FAT32 ", sizeof(boot_blk->vi.fs_type));
strncpy(boot_blk->vi.volume_label, volume_label, sizeof(boot_blk->vi.volume_label));
memcpy(boot_blk->boot_code, boot_code, sizeof(boot_code));
STORE_LE(boot_blk->boot_sign, BOOT_SIGN);
STORE_LE(info->signature1, FAT_FSINFO_SIG1);
STORE_LE(info->signature2, FAT_FSINFO_SIG2);
// we've allocated cluster 2 for the root dir
STORE_LE(info->free_clusters, (total_clust - 1));
STORE_LE(info->next_cluster, 2);
STORE_LE(info->boot_sign, BOOT_SIGN);
// 1st copy
xwrite(dev, buf, bytes_per_sect * backup_boot_sector);
// 2nd copy and possibly zero sectors
xwrite(dev, buf, bytes_per_sect * (reserved_sect - backup_boot_sector));
}
{ // file allocation tables
unsigned i,j;
unsigned char *fat = (void*)buf;
memset(buf, 0, bytes_per_sect * 2);
// initial FAT entries
MARK_CLUSTER(0, 0x0fffff00 | media_byte);
MARK_CLUSTER(1, 0xffffffff);
// mark cluster 2 as EOF (used for root dir)
MARK_CLUSTER(2, EOF_FAT32);
for (i = 0; i < NUM_FATS; i++) {
xwrite(dev, buf, bytes_per_sect);
for (j = 1; j < sect_per_fat; j++)
xwrite(dev, buf + bytes_per_sect, bytes_per_sect);
}
}
// root directory
// empty directory is just a set of zero bytes
memset(buf, 0, sect_per_clust * bytes_per_sect);
if (volume_label[0]) {
// create dir entry for volume_label
struct msdos_dir_entry *de;
#if 0
struct tm tm_time;
uint16_t t, d;
#endif
de = (void*)buf;
strncpy(de->name, volume_label, sizeof(de->name));
STORE_LE(de->attr, ATTR_VOLUME);
#if 0
localtime_r(&create_time, &tm_time);
t = (tm_time.tm_sec >> 1) + (tm_time.tm_min << 5) + (tm_time.tm_hour << 11);
d = tm_time.tm_mday + ((tm_time.tm_mon+1) << 5) + ((tm_time.tm_year-80) << 9);
STORE_LE(de->time, t);
STORE_LE(de->date, d);
//STORE_LE(de->ctime_cs, 0);
de->ctime = de->time;
de->cdate = de->date;
de->adate = de->date;
#endif
}
xwrite(dev, buf, sect_per_clust * bytes_per_sect);
#if 0
if (opts & OPT_c) {
uoff_t volume_size_blocks;
unsigned start_data_sector;
unsigned start_data_block;
unsigned badblocks = 0;
int try, got;
off_t currently_testing;
char *blkbuf = xmalloc(BLOCK_SIZE * TEST_BUFFER_BLOCKS);
volume_size_blocks = (volume_size_bytes >> BLOCK_SIZE_BITS);
// N.B. the two following vars are in hard sectors, i.e. SECTOR_SIZE byte sectors!
start_data_sector = (reserved_sect + NUM_FATS * sect_per_fat) * (bytes_per_sect / SECTOR_SIZE);
start_data_block = (start_data_sector + SECTORS_PER_BLOCK - 1) / SECTORS_PER_BLOCK;
bb_info_msg("searching for bad blocks ");
currently_testing = 0;
try = TEST_BUFFER_BLOCKS;
while (currently_testing < volume_size_blocks) {
if (currently_testing + try > volume_size_blocks)
try = volume_size_blocks - currently_testing;
// perform a test on a block. return the number of blocks
// that could be read successfully.
// seek to the correct location
xlseek(dev, currently_testing * BLOCK_SIZE, SEEK_SET);
// try reading
got = read(dev, blkbuf, try * BLOCK_SIZE);
if (got < 0)
got = 0;
if (got & (BLOCK_SIZE - 1))
bb_error_msg("unexpected values in do_check: probably bugs");
got /= BLOCK_SIZE;
currently_testing += got;
if (got == try) {
try = TEST_BUFFER_BLOCKS;
continue;
}
try = 1;
if (currently_testing < start_data_block)
bb_error_msg_and_die("bad blocks before data-area: cannot make fs");
// mark all of the sectors in the block as bad
for (i = 0; i < SECTORS_PER_BLOCK; i++) {
int cluster = (currently_testing * SECTORS_PER_BLOCK + i - start_data_sector) / (int) (sect_per_clust) / (bytes_per_sect / SECTOR_SIZE);
if (cluster < 0)
bb_error_msg_and_die("invalid cluster number in mark_sector: probably bug!");
MARK_CLUSTER(cluster, BAD_FAT32);
}
badblocks++;
currently_testing++;
}
free(blkbuf);
if (badblocks)
bb_info_msg("%d bad block(s)", badblocks);
}
#endif
// cleanup
if (ENABLE_FEATURE_CLEAN_UP) {
free(buf);
close(dev);
}
return 0;
}
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