static void print_features(struct ext2_super_block * s, FILE *f)
{
	int	i, j, printed=0;
	__u32	*mask = &s->s_feature_compat, m;

	fputs("Filesystem features:", f);
	for (i=0; i <3; i++,mask++) {
		for (j=0,m=1; j < 32; j++, m<<=1) {
			if (*mask & m) {
				fprintf(f, " %s", e2p_feature2string(i, m));
				printed++;
			}
		}
	}
	if (printed == 0)
		fputs("(none)", f);
	fputs("\n", f);
}
int main (int argc, char *argv[])
{
	errcode_t	retval = 0, retval2 = 0, orig_retval = 0;
	int		exit_value = FSCK_OK;
	ext2_filsys	fs = 0;
	io_manager	io_ptr;
	struct ext2_super_block *sb;
	const char	*lib_ver_date;
	int		my_ver, lib_ver;
	e2fsck_t	ctx;
	blk_t		orig_superblock;
	struct problem_context pctx;
	int flags, run_result;
	int journal_size;
	int sysval, sys_page_size = 4096;
	__u32 features[3];
	char *cp;
	klog_init();
	E2F_DBG_INFO("e2fsck start...");
#ifdef E2FSCK_PIPE_DEBUG_
	memset(pipe_msg_temp, 0, MSG_LEN);
	memcpy(pipe_msg_temp, argv[2], strlen(argv[2]));
  	pipe_open();
	pipe_write(C_IN_START);
#endif	

	clear_problem_context(&pctx);
#ifdef MTRACE
	mtrace();
#endif
#ifdef MCHECK
	mcheck(0);
#endif
#ifdef ENABLE_NLS
	setlocale(LC_MESSAGES, "");
	setlocale(LC_CTYPE, "");
	bindtextdomain(NLS_CAT_NAME, LOCALEDIR);
	textdomain(NLS_CAT_NAME);
#endif
	my_ver = ext2fs_parse_version_string(my_ver_string);
	lib_ver = ext2fs_get_library_version(0, &lib_ver_date);
	if (my_ver > lib_ver) {
		fprintf( stderr, _("Error: ext2fs library version "
			"out of date!\n"));
		show_version_only++;
	}

	retval = PRS(argc, argv, &ctx);
	if (retval) {
		com_err("e2fsck", retval,
			_("while trying to initialize program"));
		exit(FSCK_ERROR);
	}
	reserve_stdio_fds();

	init_resource_track(&ctx->global_rtrack, NULL);
	if (!(ctx->options & E2F_OPT_PREEN) || show_version_only)
		fprintf(stderr, "e2fsck %s (%s)\n", my_ver_string,
			 my_ver_date);

	if (show_version_only) {
		fprintf(stderr, _("\tUsing %s, %s\n"),
			error_message(EXT2_ET_BASE), lib_ver_date);
		exit(FSCK_OK);
	}

	check_mount(ctx);

	if (!(ctx->options & E2F_OPT_PREEN) &&
	    !(ctx->options & E2F_OPT_NO) &&
	    !(ctx->options & E2F_OPT_YES)) {
		if (!ctx->interactive)
			fatal_error(ctx,
				    _("need terminal for interactive repairs"));
	}
	ctx->superblock = ctx->use_superblock;
restart:
#ifdef CONFIG_TESTIO_DEBUG
	if (getenv("TEST_IO_FLAGS") || getenv("TEST_IO_BLOCK")) {
		io_ptr = test_io_manager;
		test_io_backing_manager = unix_io_manager;
	} else
#endif
		io_ptr = unix_io_manager;
	flags = EXT2_FLAG_NOFREE_ON_ERROR;
	if ((ctx->options & E2F_OPT_READONLY) == 0)
		flags |= EXT2_FLAG_RW;
	if ((ctx->mount_flags & EXT2_MF_MOUNTED) == 0)
		flags |= EXT2_FLAG_EXCLUSIVE;

	retval = try_open_fs(ctx, flags, io_ptr, &fs);

	if (!ctx->superblock && !(ctx->options & E2F_OPT_PREEN) &&
	    !(ctx->flags & E2F_FLAG_SB_SPECIFIED) &&
	    ((retval == EXT2_ET_BAD_MAGIC) ||
	     (retval == EXT2_ET_CORRUPT_SUPERBLOCK) ||
	     ((retval == 0) && (retval2 = ext2fs_check_desc(fs))))) {
		if (retval2 == ENOMEM) {
			retval = retval2;
			goto failure;
		}
		if (fs->flags & EXT2_FLAG_NOFREE_ON_ERROR) {
			ext2fs_free(fs);
			fs = NULL;
		}
		if (!fs || (fs->group_desc_count > 1)) {
			printf(_("%s: %s trying backup blocks...\n"),
			       ctx->program_name,
			       retval ? _("Superblock invalid,") :
			       _("Group descriptors look bad..."));
			orig_superblock = ctx->superblock;
			get_backup_sb(ctx, fs, ctx->filesystem_name, io_ptr);
			if (fs)
				ext2fs_close(fs);
			orig_retval = retval;
			retval = try_open_fs(ctx, flags, io_ptr, &fs);
			if ((orig_retval == 0) && retval != 0) {
				if (fs)
					ext2fs_close(fs);
				com_err(ctx->program_name, retval,
					"when using the backup blocks");
				printf(_("%s: going back to original "
					 "superblock\n"), ctx->program_name);
				ctx->superblock = orig_superblock;
				retval = try_open_fs(ctx, flags, io_ptr, &fs);
			}
		}
	}
	if (((retval == EXT2_ET_UNSUPP_FEATURE) ||
	     (retval == EXT2_ET_RO_UNSUPP_FEATURE)) &&
	    fs && fs->super) {
		sb = fs->super;
		features[0] = (sb->s_feature_compat &
			       ~EXT2_LIB_FEATURE_COMPAT_SUPP);
		features[1] = (sb->s_feature_incompat &
			       ~EXT2_LIB_FEATURE_INCOMPAT_SUPP);
		features[2] = (sb->s_feature_ro_compat &
			       ~EXT2_LIB_FEATURE_RO_COMPAT_SUPP);
		if (features[0] || features[1] || features[2])
			goto print_unsupp_features;
	}
failure:
	if (retval) {
		if (orig_retval)
			retval = orig_retval;
		com_err(ctx->program_name, retval, _("while trying to open %s"),
			ctx->filesystem_name);
		if (retval == EXT2_ET_REV_TOO_HIGH) {
			printf(_("The filesystem revision is apparently "
			       "too high for this version of e2fsck.\n"
			       "(Or the filesystem superblock "
			       "is corrupt)\n\n"));
			fix_problem(ctx, PR_0_SB_CORRUPT, &pctx);
		} else if (retval == EXT2_ET_SHORT_READ)
			printf(_("Could this be a zero-length partition?\n"));
		else if ((retval == EPERM) || (retval == EACCES))
			printf(_("You must have %s access to the "
			       "filesystem or be root\n"),
			       (ctx->options & E2F_OPT_READONLY) ?
			       "r/o" : "r/w");
		else if (retval == ENXIO)
			printf(_("Possibly non-existent or swap device?\n"));
		else if (retval == EBUSY)
			printf(_("Filesystem mounted or opened exclusively "
				 "by another program?\n"));
		else if (retval == ENOENT)
			printf(_("Possibly non-existent device?\n"));
#ifdef EROFS
		else if (retval == EROFS)
			printf(_("Disk write-protected; use the -n option "
			       "to do a read-only\n"
			       "check of the device.\n"));
#endif
		else
			fix_problem(ctx, PR_0_SB_CORRUPT, &pctx);
		fatal_error(ctx, 0);
	}
	/*
	 * We only update the master superblock because (a) paranoia;
	 * we don't want to corrupt the backup superblocks, and (b) we
	 * don't need to update the mount count and last checked
	 * fields in the backup superblock (the kernel doesn't update
	 * the backup superblocks anyway).  With newer versions of the
	 * library this flag is set by ext2fs_open2(), but we set this
	 * here just to be sure.  (No, we don't support e2fsck running
	 * with some other libext2fs than the one that it was shipped
	 * with, but just in case....)
	 */
	fs->flags |= EXT2_FLAG_MASTER_SB_ONLY;

	if (!(ctx->flags & E2F_FLAG_GOT_DEVSIZE)) {
		__u32 blocksize = EXT2_BLOCK_SIZE(fs->super);
		int need_restart = 0;

		pctx.errcode = ext2fs_get_device_size2(ctx->filesystem_name,
						       blocksize,
						       &ctx->num_blocks);
		/*
		 * The floppy driver refuses to allow anyone else to
		 * open the device if has been opened with O_EXCL;
		 * this is unlike other block device drivers in Linux.
		 * To handle this, we close the filesystem and then
		 * reopen the filesystem after we get the device size.
		 */
		if (pctx.errcode == EBUSY) {
			ext2fs_close(fs);
			need_restart++;
			pctx.errcode =
				ext2fs_get_device_size2(ctx->filesystem_name,
							blocksize,
							&ctx->num_blocks);
		}
		if (pctx.errcode == EXT2_ET_UNIMPLEMENTED)
			ctx->num_blocks = 0;
		else if (pctx.errcode) {
			fix_problem(ctx, PR_0_GETSIZE_ERROR, &pctx);
			ctx->flags |= E2F_FLAG_ABORT;
			fatal_error(ctx, 0);
		}
		ctx->flags |= E2F_FLAG_GOT_DEVSIZE;
		if (need_restart)
			goto restart;
	}

	ctx->fs = fs;
	fs->priv_data = ctx;
	fs->now = ctx->now;
	sb = fs->super;
	if (sb->s_rev_level > E2FSCK_CURRENT_REV) {
		com_err(ctx->program_name, EXT2_ET_REV_TOO_HIGH,
			_("while trying to open %s"),
			ctx->filesystem_name);
	get_newer:
		fatal_error(ctx, _("Get a newer version of e2fsck!"));
	}

	/*
	 * Set the device name, which is used whenever we print error
	 * or informational messages to the user.
	 */
	if (ctx->device_name == 0 &&
	    (sb->s_volume_name[0] != 0)) {
		ctx->device_name = string_copy(ctx, sb->s_volume_name,
					       sizeof(sb->s_volume_name));
	}
	if (ctx->device_name == 0)
		ctx->device_name = string_copy(ctx, ctx->filesystem_name, 0);
	for (cp = ctx->device_name; *cp; cp++)
		if (isspace(*cp) || *cp == ':')
			*cp = '_';

	ehandler_init(fs->io);

	if ((ctx->mount_flags & EXT2_MF_MOUNTED) &&
	    !(sb->s_feature_incompat & EXT3_FEATURE_INCOMPAT_RECOVER))
		goto skip_journal;

	/*
	 * Make sure the ext3 superblock fields are consistent.
	 */
	retval = e2fsck_check_ext3_journal(ctx);
	if (retval) {
		com_err(ctx->program_name, retval,
			_("while checking ext3 journal for %s"),
			ctx->device_name);
		fatal_error(ctx, 0);
	}

	/*
	 * Check to see if we need to do ext3-style recovery.  If so,
	 * do it, and then restart the fsck.
	 */
	if (sb->s_feature_incompat & EXT3_FEATURE_INCOMPAT_RECOVER) {
		if (ctx->options & E2F_OPT_READONLY) {
			printf(_("Warning: skipping journal recovery "
				 "because doing a read-only filesystem "
				 "check.\n"));
			io_channel_flush(ctx->fs->io);
		} else {
			if (ctx->flags & E2F_FLAG_RESTARTED) {
				/*
				 * Whoops, we attempted to run the
				 * journal twice.  This should never
				 * happen, unless the hardware or
				 * device driver is being bogus.
				 */
				com_err(ctx->program_name, 0,
					_("unable to set superblock flags on %s\n"), ctx->device_name);
				fatal_error(ctx, 0);
			}
			retval = e2fsck_run_ext3_journal(ctx);
			if (retval) {
				com_err(ctx->program_name, retval,
				_("while recovering ext3 journal of %s"),
					ctx->device_name);
				fatal_error(ctx, 0);
			}
			ext2fs_close(ctx->fs);
			ctx->fs = 0;
			ctx->flags |= E2F_FLAG_RESTARTED;
			goto restart;
		}
	}

skip_journal:
	/*
	 * Check for compatibility with the feature sets.  We need to
	 * be more stringent than ext2fs_open().
	 */
	features[0] = sb->s_feature_compat & ~EXT2_LIB_FEATURE_COMPAT_SUPP;
	features[1] = sb->s_feature_incompat & ~EXT2_LIB_FEATURE_INCOMPAT_SUPP;
	features[2] = (sb->s_feature_ro_compat &
		       ~EXT2_LIB_FEATURE_RO_COMPAT_SUPP);
print_unsupp_features:
	if (features[0] || features[1] || features[2]) {
		int	i, j;
		__u32	*mask = features, m;

		fprintf(stderr, _("%s has unsupported feature(s):"),
			ctx->filesystem_name);

		for (i=0; i <3; i++,mask++) {
			for (j=0,m=1; j < 32; j++, m<<=1) {
				if (*mask & m)
					fprintf(stderr, " %s",
						e2p_feature2string(i, m));
			}
		}
		putc('\n', stderr);
		goto get_newer;
	}
#ifdef ENABLE_COMPRESSION
	if (sb->s_feature_incompat & EXT2_FEATURE_INCOMPAT_COMPRESSION)
		com_err(ctx->program_name, 0,
			_("Warning: compression support is experimental.\n"));
#endif
#ifndef ENABLE_HTREE
	if (sb->s_feature_compat & EXT2_FEATURE_COMPAT_DIR_INDEX) {
		com_err(ctx->program_name, 0,
			_("E2fsck not compiled with HTREE support,\n\t"
			  "but filesystem %s has HTREE directories.\n"),
			ctx->device_name);
		goto get_newer;
	}
#endif

	/*
	 * If the user specified a specific superblock, presumably the
	 * master superblock has been trashed.  So we mark the
	 * superblock as dirty, so it can be written out.
	 */
	if (ctx->superblock &&
	    !(ctx->options & E2F_OPT_READONLY))
		ext2fs_mark_super_dirty(fs);

	/*
	 * Calculate the number of filesystem blocks per pagesize.  If
	 * fs->blocksize > page_size, set the number of blocks per
	 * pagesize to 1 to avoid division by zero errors.
	 */
#ifdef _SC_PAGESIZE
	sysval = sysconf(_SC_PAGESIZE);
	if (sysval > 0)
		sys_page_size = sysval;
#endif /* _SC_PAGESIZE */
	ctx->blocks_per_page = sys_page_size / fs->blocksize;
	if (ctx->blocks_per_page == 0)
		ctx->blocks_per_page = 1;

	if (ctx->superblock)
		set_latch_flags(PR_LATCH_RELOC, PRL_LATCHED, 0);
	ext2fs_mark_valid(fs);
	check_super_block(ctx);
	if (ctx->flags & E2F_FLAG_SIGNAL_MASK)
		fatal_error(ctx, 0);
	check_if_skip(ctx);
	check_resize_inode(ctx);
	if (bad_blocks_file)
		read_bad_blocks_file(ctx, bad_blocks_file, replace_bad_blocks);
	else if (cflag)
		read_bad_blocks_file(ctx, 0, !keep_bad_blocks); /* Test disk */
	if (ctx->flags & E2F_FLAG_SIGNAL_MASK)
		fatal_error(ctx, 0);

	/*
	 * Mark the system as valid, 'til proven otherwise
	 */
	ext2fs_mark_valid(fs);

	retval = ext2fs_read_bb_inode(fs, &fs->badblocks);
	if (retval) {
		com_err(ctx->program_name, retval,
			_("while reading bad blocks inode"));
		preenhalt(ctx);
		printf(_("This doesn't bode well,"
			 " but we'll try to go on...\n"));
	}

	/*
	 * Save the journal size in megabytes.
	 * Try and use the journal size from the backup else let e2fsck
	 * find the default journal size.
	 */
	if (sb->s_jnl_backup_type == EXT3_JNL_BACKUP_BLOCKS)
		journal_size = sb->s_jnl_blocks[16] >> 20;
	else