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。

	ntfs_inode_mark_dirty(ni);
	/* Done! */
	free(fn);
	free(si);
	ntfs_log_trace("Done.\n");
	return ni;
err_out:
	ntfs_log_trace("Failed.\n");

	if (rollback_sd)
		ntfs_attr_remove(ni, AT_SECURITY_DESCRIPTOR, AT_UNNAMED, 0);
	
	if (rollback_data)
		ntfs_attr_remove(ni, AT_DATA, AT_UNNAMED, 0);
	/*
	 * Free extent MFT records (should not exist any with current
	 * ntfs_create implementation, but for any case if something will be
	 * changed in the future).
	 */
	while (ni->nr_extents)
		if (ntfs_mft_record_free(ni->vol, *(ni->extent_nis))) {
			err = errno;
			ntfs_log_error("Failed to free extent MFT record.  "
					"Leaving inconsistent metadata.\n");
		}
	if (ntfs_mft_record_free(ni->vol, ni))
		ntfs_log_error("Failed to free MFT record.  "
				"Leaving inconsistent metadata. Run chkdsk.\n");
	free(fn);
	free(si);
	errno = err;
	return NULL;
}

/**
 * Some wrappers around __ntfs_create() ...
 */

ntfs_inode *ntfs_create(ntfs_inode *dir_ni, ntfschar *name, u8 name_len,
		dev_t type)
{
	if (type != S_IFREG && type != S_IFDIR && type != S_IFIFO &&
			type != S_IFSOCK) {
		ntfs_log_error("Invalid arguments.\n");
		return NULL;
	}
	return __ntfs_create(dir_ni, name, name_len, type, 0, NULL, 0);
}

ntfs_inode *ntfs_create_device(ntfs_inode *dir_ni, ntfschar *name, u8 name_len,
		dev_t type, dev_t dev)
{
	if (type != S_IFCHR && type != S_IFBLK) {
		ntfs_log_error("Invalid arguments.\n");
		return NULL;
	}
	return __ntfs_create(dir_ni, name, name_len, type, dev, NULL, 0);
}

ntfs_inode *ntfs_create_symlink(ntfs_inode *dir_ni, ntfschar *name, u8 name_len,
		ntfschar *target, int target_len)
{
	if (!target || !target_len) {
		ntfs_log_error("%s: Invalid argument (%p, %d)\n", __FUNCTION__,
			       target, target_len);
		return NULL;
	}
	return __ntfs_create(dir_ni, name, name_len, S_IFLNK, 0,
			target, target_len);
}

int ntfs_check_empty_dir(ntfs_inode *ni)
{
	ntfs_attr *na;
	int ret = 0;
	
	if (!(ni->mrec->flags & MFT_RECORD_IS_DIRECTORY))
		return 0;

	na = ntfs_attr_open(ni, AT_INDEX_ROOT, NTFS_INDEX_I30, 4);
	if (!na) {
		errno = EIO;
		ntfs_log_perror("Failed to open directory");
		return -1;
	}
	
	/* Non-empty directory? */
	if ((na->data_size != sizeof(INDEX_ROOT) + sizeof(INDEX_ENTRY_HEADER))){
		/* Both ENOTEMPTY and EEXIST are ok. We use the more common. */
		errno = ENOTEMPTY;
		ntfs_log_debug("Directory is not empty\n");
		ret = -1;
	}
	
	ntfs_attr_close(na);
	return ret;
}

static int ntfs_check_unlinkable_dir(ntfs_inode *ni, FILE_NAME_ATTR *fn)
{
	int link_count = le16_to_cpu(ni->mrec->link_count);
	int ret;
	
	ret = ntfs_check_empty_dir(ni);
	if (!ret || errno != ENOTEMPTY)
		return ret;
	/* 
	 * Directory is non-empty, so we can unlink only if there is more than
	 * one "real" hard link, i.e. links aren't different DOS and WIN32 names
	 */
	if ((link_count == 1) || 
	    (link_count == 2 && fn->file_name_type == FILE_NAME_DOS)) {
		errno = ENOTEMPTY;
		ntfs_log_debug("Non-empty directory without hard links\n");
		goto no_hardlink;
	}
	
	ret = 0;
no_hardlink:	
	return ret;
}

/**
 * ntfs_delete - delete file or directory from ntfs volume
 * @ni:		ntfs inode for object to delte
 * @dir_ni:	ntfs inode for directory in which delete object
 * @name:	unicode name of the object to delete
 * @name_len:	length of the name in unicode characters
 *
 * @ni is always closed after the call to this function (even if it failed),
 * user does not need to call ntfs_inode_close himself.
 *
 * Return 0 on success or -1 on error with errno set to the error code.
 */
int ntfs_delete(ntfs_inode *ni, ntfs_inode *dir_ni, ntfschar *name, u8 name_len)
{
	ntfs_attr_search_ctx *actx = NULL;
	FILE_NAME_ATTR *fn = NULL;
	BOOL looking_for_dos_name = FALSE, looking_for_win32_name = FALSE;
	BOOL case_sensitive_match = TRUE;
	int err = 0;

	ntfs_log_trace("Entering.\n");
	
	if (!ni || !dir_ni || !name || !name_len) {
		ntfs_log_error("Invalid arguments.\n");
		errno = EINVAL;
		goto err_out;
	}
	if (ni->nr_extents == -1)
		ni = ni->base_ni;
	if (dir_ni->nr_extents == -1)
		dir_ni = dir_ni->base_ni;
	/*
	 * Search for FILE_NAME attribute with such name. If it's in POSIX or
	 * WIN32_AND_DOS namespace, then simply remove it from index and inode.
	 * If filename in DOS or in WIN32 namespace, then remove DOS name first,
	 * only then remove WIN32 name.
	 */
	actx = ntfs_attr_get_search_ctx(ni, NULL);
	if (!actx)
		goto err_out;
search:
	while (!ntfs_attr_lookup(AT_FILE_NAME, AT_UNNAMED, 0, CASE_SENSITIVE,
			0, NULL, 0, actx)) {
		char *s;
		BOOL case_sensitive = IGNORE_CASE;

		errno = 0;
		fn = (FILE_NAME_ATTR*)((u8*)actx->attr +
				le16_to_cpu(actx->attr->value_offset));
		s = ntfs_attr_name_get(fn->file_name, fn->file_name_length);
		ntfs_log_trace("name: '%s'  type: %d  dos: %d  win32: %d  "
			       "case: %d\n", s, fn->file_name_type,
			       looking_for_dos_name, looking_for_win32_name,
			       case_sensitive_match);
		ntfs_attr_name_free(&s);
		if (looking_for_dos_name) {
			if (fn->file_name_type == FILE_NAME_DOS)
				break;
			else
				continue;
		}
		if (looking_for_win32_name) {
			if  (fn->file_name_type == FILE_NAME_WIN32)
				break;
			else
				continue;
		}
		
		/* Ignore hard links from other directories */
		if (dir_ni->mft_no != MREF_LE(fn->parent_directory)) {
			ntfs_log_debug("MFT record numbers don't match "
				       "(%llu != %llu)\n", dir_ni->mft_no, 
				       MREF_LE(fn->parent_directory));
			continue;
		}
		     
		if (fn->file_name_type == FILE_NAME_POSIX || case_sensitive_match)
			case_sensitive = CASE_SENSITIVE;
		
		if (ntfs_names_are_equal(fn->file_name, fn->file_name_length,
					 name, name_len, case_sensitive, 
					 ni->vol->upcase, ni->vol->upcase_len)){
			
			if (fn->file_name_type == FILE_NAME_WIN32) {
				looking_for_dos_name = TRUE;
				ntfs_attr_reinit_search_ctx(actx);
				continue;
			}
			if (fn->file_name_type == FILE_NAME_DOS)
				looking_for_dos_name = TRUE;
			break;
		}
	}
	if (errno) {
		/*
		 * If case sensitive search failed, then try once again
		 * ignoring case.
		 */
		if (errno == ENOENT && case_sensitive_match) {
			case_sensitive_match = FALSE;
			ntfs_attr_reinit_search_ctx(actx);
			goto search;
		}
		goto err_out;
	}
	
	if (ntfs_check_unlinkable_dir(ni, fn) < 0)
		goto err_out;
		
	if (ntfs_index_remove(dir_ni, fn, le32_to_cpu(actx->attr->value_length)))
		goto err_out;
	
	if (ntfs_attr_record_rm(actx))
		goto err_out;
	
	ni->mrec->link_count = cpu_to_le16(le16_to_cpu(
			ni->mrec->link_count) - 1);
	
	ntfs_inode_mark_dirty(ni);
	if (looking_for_dos_name) {
		looking_for_dos_name = FALSE;
		looking_for_win32_name = TRUE;
		ntfs_attr_reinit_search_ctx(actx);
		goto search;
	}
	/* TODO: Update object id, quota and securiry indexes if required. */
	/*
	 * If hard link count is not equal to zero then we are done. In other
	 * case there are no reference to this inode left, so we should free all
	 * non-resident attributes and mark all MFT record as not in use.
	 */
	if (ni->mrec->link_count) {
		ntfs_inode_update_times(ni, NTFS_UPDATE_CTIME);
		goto ok;
	}
	ntfs_attr_reinit_search_ctx(actx);
	while (!ntfs_attrs_walk(actx)) {
		if (actx->attr->non_resident) {
			runlist *rl;

			rl = ntfs_mapping_pairs_decompress(ni->vol, actx->attr,
					NULL);
			if (!rl) {
				err = errno;
				ntfs_log_error("Failed to decompress runlist.  "
						"Leaving inconsistent metadata.\n");
				continue;
			}
			if (ntfs_cluster_free_from_rl(ni->vol, rl)) {
				err = errno;
				ntfs_log_error("Failed to free clusters.  "
						"Leaving inconsistent metadata.\n");
				continue;
			}
			free(rl);
		}
	}
	if (errno != ENOENT) {
		err = errno;
		ntfs_log_error("Attribute enumeration failed.  "
				"Probably leaving inconsistent metadata.\n");
	}
	/* All extents should be attached after attribute walk. */
	while (ni->nr_extents)
		if (ntfs_mft_record_free(ni->vol, *(ni->extent_nis))) {
			err = errno;
			ntfs_log_error("Failed to free extent MFT record.  "
					"Leaving inconsistent metadata.\n");
		}
	if (ntfs_mft_record_free(ni->vol, ni)) {
		err = errno;
		ntfs_log_error("Failed to free base MFT record.  "
				"Leaving inconsistent metadata.\n");
	}
	ni = NULL;
ok:	
	ntfs_inode_update_times(dir_ni, NTFS_UPDATE_MCTIME);
out:
	if (actx)
		ntfs_attr_put_search_ctx(actx);
	if (ntfs_inode_close(dir_ni) && !err)
		err = errno;
	if (ntfs_inode_close(ni) && !err)
		err = errno;
	if (err) {
		errno = err;
		ntfs_log_debug("Could not delete file: %s\n", strerror(errno));
		return -1;
	}
	ntfs_log_trace("Done.\n");
	return 0;
err_out:
	err = errno;
	goto out;
}

/**
 * ntfs_link - create hard link for file or directory
 * @ni:		ntfs inode for object to create hard link
 * @dir_ni:	ntfs inode for directory in which new link should be placed
 * @name:	unicode name of the new link
 * @name_len:	length of the name in unicode characters
 *
 * NOTE: At present we allow creating hardlinks to directories, we use them
 * in a temporary state during rename. But it's defenitely bad idea to have
 * hard links to directories as a result of operation.
 * FIXME: Create internal  __ntfs_link that allows hard links to a directories
 * and external ntfs_link that do not. Write ntfs_rename that uses __ntfs_link.
 *
 * Return 0 on success or -1 on error with errno set to the error code.
 */
int ntfs_link(ntfs_inode *ni, ntfs_inode *dir_ni, ntfschar *name, u8 name_len)
{
	FILE_NAME_ATTR *fn = NULL;
	int fn_len, err;

	ntfs_log_trace("Entering.\n");
	
	if (!ni || !dir_ni || !name || !name_len || 
			ni->mft_no == dir_ni->mft_no) {
		err = EINVAL;
		ntfs_log_perror("ntfs_link wrong arguments");
		goto err_out;
	}
	
	if (ni->flags & FILE_ATTR_REPARSE_POINT) {
		err = EOPNOTSUPP;
		goto err_out;
	}
	
	/* 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;
	fn->file_attributes = ni->flags;
	if (ni->mrec->flags & MFT_RECORD_IS_DIRECTORY)
		fn->file_attributes |= FILE_ATTR_I30_INDEX_PRESENT;
	fn->allocated_size = cpu_to_sle64(ni->allocated_size);
	fn->data_size = cpu_to_sle64(ni->data_size);
	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);
	memcpy(fn->file_name, name, name_len * sizeof(ntfschar));
	/* 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 filename to the index");
		goto err_out;
	}
	/* Add FILE_NAME attribute to inode. */
	if (ntfs_attr_add(ni, AT_FILE_NAME, AT_UNNAMED, 0, (u8*)fn, fn_len)) {
		ntfs_log_error("Failed to add FILE_NAME attribute.\n");
		err = errno;
		/* Try to remove just added attribute from index. */
		if (ntfs_index_remove(dir_ni, fn, fn_len))
			goto rollback_failed;
		goto err_out;
	}
	/* Increment hard links count. */
	ni->mrec->link_count = cpu_to_le16(le16_to_cpu(
			ni->mrec->link_count) + 1);
	/* Done! */
	ntfs_inode_mark_dirty(ni);
	free(fn);
	ntfs_log_trace("Done.\n");
	return 0;
rollback_failed:
	ntfs_log_error("Rollback failed. Leaving inconsistent metadata.\n");
err_out:
	free(fn);
	errno = err;
	return -1;
}