dd: code shrink
[oweals/busybox.git] / util-linux / mkfs_ext2.c
index 44fb4025003adcb4316408a7554be3c66e337446..3258d7eeeb25286f8da5fbc8164189851aa64dda 100644 (file)
@@ -5,20 +5,53 @@
  *
  * Busybox'ed (2009) by Vladimir Dronnikov <dronnikov@gmail.com>
  *
- * Licensed under GPLv2, see file LICENSE in this tarball for details.
+ * Licensed under GPLv2, see file LICENSE in this source tree.
  */
+
+//usage:#define mkfs_ext2_trivial_usage
+//usage:       "[-Fn] "
+/* //usage:    "[-c|-l filename] " */
+//usage:       "[-b BLK_SIZE] "
+/* //usage:    "[-f fragment-size] [-g blocks-per-group] " */
+//usage:       "[-i INODE_RATIO] [-I INODE_SIZE] "
+/* //usage:    "[-j] [-J journal-options] [-N number-of-inodes] " */
+//usage:       "[-m RESERVED_PERCENT] "
+/* //usage:    "[-o creator-os] [-O feature[,...]] [-q] " */
+/* //usage:    "[r fs-revision-level] [-E extended-options] [-v] [-F] " */
+//usage:       "[-L LABEL] "
+/* //usage:    "[-M last-mounted-directory] [-S] [-T filesystem-type] " */
+//usage:       "BLOCKDEV [KBYTES]"
+//usage:#define mkfs_ext2_full_usage "\n\n"
+//usage:       "       -b BLK_SIZE     Block size, bytes"
+/* //usage:  "\n       -c              Check device for bad blocks" */
+/* //usage:  "\n       -E opts         Set extended options" */
+/* //usage:  "\n       -f size         Fragment size in bytes" */
+//usage:     "\n       -F              Force"
+/* //usage:  "\n       -g N            Number of blocks in a block group" */
+//usage:     "\n       -i RATIO        Max number of files is filesystem_size / RATIO"
+//usage:     "\n       -I BYTES        Inode size (min 128)"
+/* //usage:  "\n       -j              Create a journal (ext3)" */
+/* //usage:  "\n       -J opts         Set journal options (size/device)" */
+/* //usage:  "\n       -l file         Read bad blocks list from file" */
+//usage:     "\n       -L LBL          Volume label"
+//usage:     "\n       -m PERCENT      Percent of blocks to reserve for admin"
+/* //usage:  "\n       -M dir          Set last mounted directory" */
+//usage:     "\n       -n              Dry run"
+/* //usage:  "\n       -N N            Number of inodes to create" */
+/* //usage:  "\n       -o os           Set the 'creator os' field" */
+/* //usage:  "\n       -O features     Dir_index/filetype/has_journal/journal_dev/sparse_super" */
+/* //usage:  "\n       -q              Quiet" */
+/* //usage:  "\n       -r rev          Set filesystem revision" */
+/* //usage:  "\n       -S              Write superblock and group descriptors only" */
+/* //usage:  "\n       -T fs-type      Set usage type (news/largefile/largefile4)" */
+/* //usage:  "\n       -v              Verbose" */
+
 #include "libbb.h"
 #include <linux/fs.h>
-#include <linux/ext2_fs.h>
-#include "volume_id/volume_id_internal.h"
-
-#define        ENABLE_FEATURE_MKFS_EXT2_RESERVED_GDT 0
-#define        ENABLE_FEATURE_MKFS_EXT2_DIR_INDEX    1
+#include "bb_e2fs_defs.h"
 
-// from e2fsprogs
-#define s_reserved_gdt_blocks s_padding1
-#define s_mkfs_time           s_reserved[0]
-#define s_flags               s_reserved[22]
+#define ENABLE_FEATURE_MKFS_EXT2_RESERVED_GDT 0
+#define ENABLE_FEATURE_MKFS_EXT2_DIR_INDEX    1
 
 #define EXT2_HASH_HALF_MD4       1
 #define EXT2_FLAGS_SIGNED_HASH   0x0001
@@ -29,9 +62,9 @@ char BUG_wrong_field_size(void);
 #define STORE_LE(field, value) \
 do { \
        if (sizeof(field) == 4) \
-               field = cpu_to_le32(value); \
+               field = SWAP_LE32(value); \
        else if (sizeof(field) == 2) \
-               field = cpu_to_le16(value); \
+               field = SWAP_LE16(value); \
        else if (sizeof(field) == 1) \
                field = (value); \
        else \
@@ -39,7 +72,7 @@ do { \
 } while (0)
 
 #define FETCH_LE32(field) \
-       (sizeof(field) == 4 ? cpu_to_le32(field) : BUG_wrong_field_size())
+       (sizeof(field) == 4 ? SWAP_LE32(field) : BUG_wrong_field_size())
 
 // All fields are little-endian
 struct ext2_dir {
@@ -141,7 +174,7 @@ static void PUT(uint64_t off, void *buf, uint32_t size)
 // only for directories, which never need i_size_high).
 //
 // Standard mke2fs creates a filesystem with 256-byte inodes if it is
-// bigger than 0.5GB. So far, we do not do this.
+// bigger than 0.5GB.
 
 // Standard mke2fs 1.41.9:
 // Usage: mke2fs [-c|-l filename] [-b block-size] [-f fragment-size]
@@ -211,25 +244,28 @@ int mkfs_ext2_main(int argc UNUSED_PARAM, char **argv)
 
        // using global "option_mask32" instead of local "opts":
        // we are register starved here
-       opt_complementary = "-1:b+:m+:i+";
+       opt_complementary = "-1:b+:i+:I+:m+";
        /*opts =*/ getopt32(argv, "cl:b:f:i:I:J:G:N:m:o:g:L:M:O:r:E:T:U:jnqvFS",
-               NULL, &bs, NULL, &bpi, &user_inodesize, NULL, NULL, NULL,
-               &reserved_percent, NULL, NULL, &label, NULL, NULL, NULL, NULL, NULL, NULL);
+               /*lbfi:*/ NULL, &bs, NULL, &bpi,
+               /*IJGN:*/ &user_inodesize, NULL, NULL, NULL,
+               /*mogL:*/ &reserved_percent, NULL, NULL, &label,
+               /*MOrE:*/ NULL, NULL, NULL, NULL,
+               /*TU:*/ NULL, NULL);
        argv += optind; // argv[0] -- device
 
-       // check the device is a block device
+       // open the device, check the device is a block device
        xmove_fd(xopen(argv[0], O_WRONLY), fd);
-       fstat(fd, &st);
+       xfstat(fd, &st, argv[0]);
        if (!S_ISBLK(st.st_mode) && !(option_mask32 & OPT_F))
-               bb_error_msg_and_die("not a block device");
+               bb_error_msg_and_die("%s: not a block device", argv[0]);
 
        // check if it is mounted
        // N.B. what if we format a file? find_mount_point will return false negative since
-       // it is loop block device which mounted!
+       // it is loop block device which is mounted!
        if (find_mount_point(argv[0], 0))
                bb_error_msg_and_die("can't format mounted filesystem");
 
-       // open the device, get size in kbytes
+       // get size in kbytes
        kilobytes = get_volume_size_in_bytes(fd, argv[1], 1024, /*extend:*/ !(option_mask32 & OPT_n)) / 1024;
 
        bytes_per_inode = 16384;
@@ -441,8 +477,10 @@ int mkfs_ext2_main(int argc UNUSED_PARAM, char **argv)
        STORE_LE(sb->s_magic, EXT2_SUPER_MAGIC);
        STORE_LE(sb->s_inode_size, inodesize);
        // set "Required extra isize" and "Desired extra isize" fields to 28
-       if (inodesize != sizeof(*inode))
-               STORE_LE(sb->s_reserved[21], 0x001C001C);
+       if (inodesize != sizeof(*inode)) {
+               STORE_LE(sb->s_min_extra_isize, 0x001c);
+               STORE_LE(sb->s_want_extra_isize, 0x001c);
+       }
        STORE_LE(sb->s_first_ino, EXT2_GOOD_OLD_FIRST_INO);
        STORE_LE(sb->s_log_block_size, blocksize_log2 - EXT2_MIN_BLOCK_LOG_SIZE);
        STORE_LE(sb->s_log_frag_size, blocksize_log2 - EXT2_MIN_BLOCK_LOG_SIZE);
@@ -574,7 +612,11 @@ int mkfs_ext2_main(int argc UNUSED_PARAM, char **argv)
 
        // zero boot sectors
        memset(buf, 0, blocksize);
-       PUT(0, buf, 1024); // N.B. 1024 <= blocksize, so buf[0..1023] contains zeros
+       // Disabled: standard mke2fs doesn't do this, and
+       // on SPARC this destroys Sun disklabel.
+       // Users who need/want zeroing can easily do it with dd.
+       //PUT(0, buf, 1024); // N.B. 1024 <= blocksize, so buf[0..1023] contains zeros
+
        // zero inode tables
        for (i = 0; i < ngroups; ++i)
                for (n = 0; n < inode_table_blocks; ++n)