| /* 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> |
| #include "volume_id/volume_id_internal.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 { |
| char boot_jump[3]; /* 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] = cpu_to_le32(value) |
| |
| void BUG_unsupported_field_size(void); |
| #define STORE_LE(field, value) \ |
| do { \ |
| if (sizeof(field) == 4) \ |
| field = cpu_to_le32(value); \ |
| else if (sizeof(field) == 2) \ |
| field = cpu_to_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, ¶m); |
| 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, "\xeb\x58\x90" "mkdosfs"); // system_id[8] included :) |
| 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; |
| } |