2 * runlist.h - Exports for runlist handling. Part of the Linux-NTFS project.
4 * Copyright (c) 2002 Anton Altaparmakov
5 * Copyright (c) 2002 Richard Russon
7 * This program/include file is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License as published
9 * by the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
12 * This program/include file is distributed in the hope that it will be
13 * useful, but WITHOUT ANY WARRANTY; without even the implied warranty
14 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
17 * You should have received a copy of the GNU General Public License
18 * along with this program (in the main directory of the Linux-NTFS
19 * distribution in the file COPYING); if not, write to the Free Software
20 * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23 #ifndef _NTFS_RUNLIST_H
24 #define _NTFS_RUNLIST_H
28 /* Forward declarations */
29 typedef struct _runlist_element runlist_element;
30 typedef runlist_element runlist;
36 * runlist_element - in memory vcn to lcn mapping array element
37 * @vcn: starting vcn of the current array element
38 * @lcn: starting lcn of the current array element
39 * @length: length in clusters of the current array element
41 * The last vcn (in fact the last vcn + 1) is reached when length == 0.
43 * When lcn == -1 this means that the count vcns starting at vcn are not
44 * physically allocated (i.e. this is a hole / data is sparse).
46 struct _runlist_element {/* In memory vcn to lcn mapping structure element. */
47 VCN vcn; /* vcn = Starting virtual cluster number. */
48 LCN lcn; /* lcn = Starting logical cluster number. */
49 s64 length; /* Run length in clusters. */
52 extern LCN ntfs_rl_vcn_to_lcn(const runlist_element *rl, const VCN vcn);
54 extern s64 ntfs_rl_pwrite(const ntfs_volume *vol, const runlist_element *rl,
55 const s64 pos, s64 count, void *b);
57 extern runlist_element *ntfs_runlists_merge(runlist_element *drl,
58 runlist_element *srl);
60 extern runlist_element *ntfs_mapping_pairs_decompress(const ntfs_volume *vol,
61 const ATTR_RECORD *attr, runlist_element *old_rl);
63 extern int ntfs_get_nr_significant_bytes(const s64 n);
65 extern int ntfs_get_size_for_mapping_pairs(const ntfs_volume *vol,
66 const runlist_element *rl);
68 extern int ntfs_write_significant_bytes(s8 *dst, const s8 *dst_max,
71 extern int ntfs_mapping_pairs_build(const ntfs_volume *vol, s8 *dst,
72 const int dst_len, const runlist_element *rl);
74 extern int ntfs_rl_truncate(runlist **rl, const VCN start_vcn);
76 #endif /* defined _NTFS_RUNLIST_H */