dir.c

LINUX下读写NTFS分区的工具。 已经集成了通过LIBCONV库支持中文的代码。

				INDEX_TYPE_ROOT, ir, ie, dirent, filldir);
		if (rc) {
			ntfs_attr_put_search_ctx(ctx);
			ctx = NULL;
			goto err_out;
		}
	}
	ntfs_attr_put_search_ctx(ctx);
	ctx = NULL;

	/* If there is no index allocation attribute we are finished. */
	if (!ia_na)
		goto EOD;

	/* Advance *pos to the beginning of the index allocation. */
	*pos = vol->mft_record_size;

skip_index_root:

	if (!ia_na)
		goto done;

	/* Allocate a buffer for the current index block. */
	ia = ntfs_malloc(index_block_size);
	if (!ia)
		goto err_out;

	bmp_na = ntfs_attr_open(dir_ni, AT_BITMAP, NTFS_INDEX_I30, 4);
	if (!bmp_na) {
		ntfs_log_perror("Failed to open index bitmap attribute");
		goto dir_err_out;
	}

	/* Get the offset into the index allocation attribute. */
	ia_pos = *pos - vol->mft_record_size;

	bmp_pos = ia_pos >> index_block_size_bits;
	if (bmp_pos >> 3 >= bmp_na->data_size) {
		ntfs_log_error("Current index position exceeds index bitmap "
				"size.\n");
		goto dir_err_out;
	}

	bmp_buf_size = min(bmp_na->data_size - (bmp_pos >> 3), 4096);
	bmp = ntfs_malloc(bmp_buf_size);
	if (!bmp)
		goto err_out;

	br = ntfs_attr_pread(bmp_na, bmp_pos >> 3, bmp_buf_size, bmp);
	if (br != bmp_buf_size) {
		if (br != -1)
			errno = EIO;
		ntfs_log_perror("Failed to read from index bitmap attribute");
		goto err_out;
	}

	bmp_buf_pos = 0;
	/* If the index block is not in use find the next one that is. */
	while (!(bmp[bmp_buf_pos >> 3] & (1 << (bmp_buf_pos & 7)))) {
find_next_index_buffer:
		bmp_pos++;
		bmp_buf_pos++;
		/* If we have reached the end of the bitmap, we are done. */
		if (bmp_pos >> 3 >= bmp_na->data_size)
			goto EOD;
		ia_pos = bmp_pos << index_block_size_bits;
		if (bmp_buf_pos >> 3 < bmp_buf_size)
			continue;
		/* Read next chunk from the index bitmap. */
		bmp_buf_pos = 0;
		if ((bmp_pos >> 3) + bmp_buf_size > bmp_na->data_size)
			bmp_buf_size = bmp_na->data_size - (bmp_pos >> 3);
		br = ntfs_attr_pread(bmp_na, bmp_pos >> 3, bmp_buf_size, bmp);
		if (br != bmp_buf_size) {
			if (br != -1)
				errno = EIO;
			ntfs_log_perror("Failed to read from index bitmap attribute");
			goto err_out;
		}
	}

	ntfs_log_debug("Handling index block 0x%llx.\n", (long long)bmp_pos);

	/* Read the index block starting at bmp_pos. */
	br = ntfs_attr_mst_pread(ia_na, bmp_pos << index_block_size_bits, 1,
			index_block_size, ia);
	if (br != 1) {
		if (br != -1)
			errno = EIO;
		ntfs_log_perror("Failed to read index block");
		goto err_out;
	}

	ia_start = ia_pos & ~(s64)(index_block_size - 1);
	if (sle64_to_cpu(ia->index_block_vcn) != ia_start >>
			index_vcn_size_bits) {
		ntfs_log_error("Actual VCN (0x%llx) of index buffer is different "
				"from expected VCN (0x%llx) in inode 0x%llx.\n",
				(long long)sle64_to_cpu(ia->index_block_vcn),
				(long long)ia_start >> index_vcn_size_bits,
				(unsigned long long)dir_ni->mft_no);
		goto dir_err_out;
	}
	if (le32_to_cpu(ia->index.allocated_size) + 0x18 != index_block_size) {
		ntfs_log_error("Index buffer (VCN 0x%llx) of directory inode 0x%llx "
				"has a size (%u) differing from the directory "
				"specified size (%u).\n", (long long)ia_start >>
				index_vcn_size_bits,
				(unsigned long long)dir_ni->mft_no,
				(unsigned) le32_to_cpu(ia->index.allocated_size)
				+ 0x18, (unsigned)index_block_size);
		goto dir_err_out;
	}
	index_end = (u8*)&ia->index + le32_to_cpu(ia->index.index_length);
	if (index_end > (u8*)ia + index_block_size) {
		ntfs_log_error("Size of index buffer (VCN 0x%llx) of directory inode "
				"0x%llx exceeds maximum size.\n",
				(long long)ia_start >> index_vcn_size_bits,
				(unsigned long long)dir_ni->mft_no);
		goto dir_err_out;
	}
	/* The first index entry. */
	ie = (INDEX_ENTRY*)((u8*)&ia->index +
			le32_to_cpu(ia->index.entries_offset));
	/*
	 * Loop until we exceed valid memory (corruption case) or until we
	 * reach the last entry or until ntfs_filldir tells us it has had
	 * enough or signals an error (both covered by the rc test).
	 */
	for (;; ie = (INDEX_ENTRY*)((u8*)ie + le16_to_cpu(ie->length))) {
		ntfs_log_debug("In index allocation, offset 0x%llx.\n",
				(long long)ia_start + ((u8*)ie - (u8*)ia));
		/* Bounds checks. */
		if ((u8*)ie < (u8*)ia || (u8*)ie +
				sizeof(INDEX_ENTRY_HEADER) > index_end ||
				(u8*)ie + le16_to_cpu(ie->key_length) >
				index_end) {
			ntfs_log_error("Index entry out of bounds in directory inode "
				"0x%llx.\n", (unsigned long long)dir_ni->mft_no);
			goto dir_err_out;
		}
		/* The last entry cannot contain a name. */
		if (ie->ie_flags & INDEX_ENTRY_END)
			break;
		/* Skip index entry if continuing previous readdir. */
		if (ia_pos - ia_start > (u8*)ie - (u8*)ia)
			continue;
		/*
		 * Submit the directory entry to ntfs_filldir(), which will
		 * invoke the filldir() callback as appropriate.
		 */
		rc = ntfs_filldir(dir_ni, pos, index_vcn_size_bits,
				INDEX_TYPE_ALLOCATION, ia, ie, dirent, filldir);
		if (rc)
			goto err_out;
	}
	goto find_next_index_buffer;
EOD:
	/* We are finished, set *pos to EOD. */
	*pos = i_size + vol->mft_record_size;
done:
	free(ia);
	free(bmp);
	if (bmp_na)
		ntfs_attr_close(bmp_na);
	if (ia_na)
		ntfs_attr_close(ia_na);
	ntfs_log_debug("EOD, *pos 0x%llx, returning 0.\n", (long long)*pos);
	return 0;
dir_err_out:
	errno = EIO;
err_out:
	eo = errno;
	ntfs_log_trace("failed.\n");
	if (ctx)
		ntfs_attr_put_search_ctx(ctx);
	free(ia);
	free(bmp);
	if (bmp_na)
		ntfs_attr_close(bmp_na);
	if (ia_na)
		ntfs_attr_close(ia_na);
	errno = eo;
	return -1;
}


/**
 * __ntfs_create - create object on ntfs volume
 * @dir_ni:	ntfs inode for directory in which create new object
 * @name:	unicode name of new object
 * @name_len:	length of the name in unicode characters
 * @type:	type of the object to create
 * @dev:	major and minor device numbers (obtained from makedev())
 * @target:	target in unicode (only for symlinks)
 * @target_len:	length of target in unicode characters
 *
 * Internal, use ntfs_create{,_device,_symlink} wrappers instead.
 *
 * @type can be:
 *	S_IFREG		to create regular file
 *	S_IFDIR		to create directory
 *	S_IFBLK		to create block device
 *	S_IFCHR		to create character device
 *	S_IFLNK		to create symbolic link
 *	S_IFIFO		to create FIFO
 *	S_IFSOCK	to create socket
 * other values are invalid.
 *
 * @dev is used only if @type is S_IFBLK or S_IFCHR, in other cases its value
 * ignored.
 *
 * @target and @target_len are used only if @type is S_IFLNK, in other cases
 * their value ignored.
 *
 * Return opened ntfs inode that describes created object on success or NULL
 * on error with errno set to the error code.
 */
static ntfs_inode *__ntfs_create(ntfs_inode *dir_ni,
		ntfschar *name, u8 name_len, dev_t type, dev_t dev,
		ntfschar *target, int target_len)
{
	ntfs_inode *ni;
	int rollback_data = 0, rollback_sd = 0;
	FILE_NAME_ATTR *fn = NULL;
	STANDARD_INFORMATION *si = NULL;
	int err, fn_len, si_len;

	ntfs_log_trace("Entering.\n");
	
	/* Sanity checks. */
	if (!dir_ni || !name || !name_len) {
		ntfs_log_error("Invalid arguments.\n");
		errno = EINVAL;
		return NULL;
	}
	
	if (dir_ni->flags & FILE_ATTR_REPARSE_POINT) {
		errno = EOPNOTSUPP;
		return NULL;
	}
	
	ni = ntfs_mft_record_alloc(dir_ni->vol, NULL);
	if (!ni)
		return NULL;
	/*
	 * Create STANDARD_INFORMATION attribute. Write STANDARD_INFORMATION
	 * version 1.2, windows will upgrade it to version 3 if needed.
	 */
	si_len = offsetof(STANDARD_INFORMATION, v1_end);
	si = ntfs_calloc(si_len);
	if (!si) {
		err = errno;
		goto err_out;
	}
	si->creation_time = utc2ntfs(ni->creation_time);
	si->last_data_change_time = utc2ntfs(ni->last_data_change_time);
	si->last_mft_change_time = utc2ntfs(ni->last_mft_change_time);
	si->last_access_time = utc2ntfs(ni->last_access_time);
	if (!S_ISREG(type) && !S_ISDIR(type)) {
		si->file_attributes = FILE_ATTR_SYSTEM;
		ni->flags = FILE_ATTR_SYSTEM;
	}
	/* Add STANDARD_INFORMATION to inode. */
	if (ntfs_attr_add(ni, AT_STANDARD_INFORMATION, AT_UNNAMED, 0,
			(u8*)si, si_len)) {
		err = errno;
		ntfs_log_error("Failed to add STANDARD_INFORMATION "
				"attribute.\n");
		goto err_out;
	}
	
	if (ntfs_sd_add_everyone(ni)) {
		err = errno;
		goto err_out;
	}
	rollback_sd = 1;

	if (S_ISDIR(type)) {
		INDEX_ROOT *ir = NULL;
		INDEX_ENTRY *ie;
		int ir_len, index_len;

		/* Create INDEX_ROOT attribute. */
		index_len = sizeof(INDEX_HEADER) + sizeof(INDEX_ENTRY_HEADER);
		ir_len = offsetof(INDEX_ROOT, index) + index_len;
		ir = ntfs_calloc(ir_len);
		if (!ir) {
			err = errno;
			goto err_out;
		}
		ir->type = AT_FILE_NAME;
		ir->collation_rule = COLLATION_FILE_NAME;
		ir->index_block_size = cpu_to_le32(ni->vol->indx_record_size);
		if (ni->vol->cluster_size <= ni->vol->indx_record_size)
			ir->clusters_per_index_block =
					ni->vol->indx_record_size >>
					ni->vol->cluster_size_bits;
		else
			ir->clusters_per_index_block = 
					ni->vol->indx_record_size >>
					ni->vol->sector_size_bits;
		ir->index.entries_offset = cpu_to_le32(sizeof(INDEX_HEADER));
		ir->index.index_length = cpu_to_le32(index_len);
		ir->index.allocated_size = cpu_to_le32(index_len);
		ie = (INDEX_ENTRY*)((u8*)ir + sizeof(INDEX_ROOT));
		ie->length = cpu_to_le16(sizeof(INDEX_ENTRY_HEADER));
		ie->key_length = 0;
		ie->ie_flags = INDEX_ENTRY_END;
		/* Add INDEX_ROOT attribute to inode. */
		if (ntfs_attr_add(ni, AT_INDEX_ROOT, NTFS_INDEX_I30, 4,
				(u8*)ir, ir_len)) {
			err = errno;
			free(ir);
			ntfs_log_error("Failed to add INDEX_ROOT attribute.\n");
			goto err_out;
		}
		free(ir);
	} else {
		INTX_FILE *data;
		int data_len;

		switch (type) {
			case S_IFBLK:
			case S_IFCHR:
				data_len = offsetof(INTX_FILE, device_end);
				data = ntfs_malloc(data_len);
				if (!data) {
					err = errno;
					goto err_out;
				}
				data->major = cpu_to_le64(major(dev));
				data->minor = cpu_to_le64(minor(dev));
				if (type == S_IFBLK)
					data->magic = INTX_BLOCK_DEVICE;
				if (type == S_IFCHR)
					data->magic = INTX_CHARACTER_DEVICE;
				break;
			case S_IFLNK:
				data_len = sizeof(INTX_FILE_TYPES) +
						target_len * sizeof(ntfschar);
				data = ntfs_malloc(data_len);
				if (!data) {
					err = errno;
					goto err_out;
				}
				data->magic = INTX_SYMBOLIC_LINK;
				memcpy(data->target, target,
						target_len * sizeof(ntfschar));
				break;
			case S_IFSOCK:
				data = NULL;
				data_len = 1;
				break;
			default: /* FIFO or regular file. */
				data = NULL;
				data_len = 0;
				break;
		}
		/* Add DATA attribute to inode. */
		if (ntfs_attr_add(ni, AT_DATA, AT_UNNAMED, 0, (u8*)data,
				data_len)) {
			err = errno;
			ntfs_log_error("Failed to add DATA attribute.\n");
			free(data);
			goto err_out;
		}
		rollback_data = 1;
		free(data);
	}
	/* Create FILE_NAME attribute. */
	fn_len = sizeof(FILE_NAME_ATTR) + name_len * sizeof(ntfschar);
	fn = ntfs_calloc(fn_len);
	if (!fn) {
		err = errno;
		goto err_out;
	}
	fn->parent_directory = MK_LE_MREF(dir_ni->mft_no,
			le16_to_cpu(dir_ni->mrec->sequence_number));
	fn->file_name_length = name_len;
	fn->file_name_type = FILE_NAME_POSIX;
	if (S_ISDIR(type))
		fn->file_attributes = FILE_ATTR_I30_INDEX_PRESENT;
	if (!S_ISREG(type) && !S_ISDIR(type))
		fn->file_attributes = FILE_ATTR_SYSTEM;
	fn->creation_time = utc2ntfs(ni->creation_time);
	fn->last_data_change_time = utc2ntfs(ni->last_data_change_time);
	fn->last_mft_change_time = utc2ntfs(ni->last_mft_change_time);
	fn->last_access_time = utc2ntfs(ni->last_access_time);
	fn->data_size = cpu_to_sle64(ni->data_size);
	fn->allocated_size = cpu_to_sle64(ni->allocated_size);
	memcpy(fn->file_name, name, name_len * sizeof(ntfschar));
	/* Add FILE_NAME attribute to inode. */
	if (ntfs_attr_add(ni, AT_FILE_NAME, AT_UNNAMED, 0, (u8*)fn, fn_len)) {
		err = errno;
		ntfs_log_error("Failed to add FILE_NAME attribute.\n");
		goto err_out;
	}
	/* Add FILE_NAME attribute to index. */
	if (ntfs_index_add_filename(dir_ni, fn, MK_MREF(ni->mft_no,
			le16_to_cpu(ni->mrec->sequence_number)))) {
		err = errno;
		ntfs_log_perror("Failed to add entry to the index");
		goto err_out;
	}
	/* Set hard links count and directory flag. */
	ni->mrec->link_count = cpu_to_le16(1);
	if (S_ISDIR(type))
		ni->mrec->flags |= MFT_RECORD_IS_DIRECTORY;