1 /* LBS: An LFS-inspired filesystem backup system
2 * Copyright (C) 2007 Michael Vrable
4 * Handling of metadata written to backup snapshots. This manages the writing
5 * of file metadata into new backup snapshots, including breaking the metadata
6 * log apart across separate objects. Eventually this should include unified
7 * handling of the statcache, and re-use of metadata between snapshots.
10 #ifndef _LBS_METADATA_H
11 #define _LBS_METADATA_H
14 #include <sys/types.h>
24 /* Metadata for a single inode, ready to be written out. */
33 class MetadataWriter {
35 MetadataWriter(TarSegmentStore *store, const char *path,
36 const char *snapshot_name, const char *snapshot_scheme);
37 void add(dictionary info);
38 ObjectReference close();
40 bool find(const std::string& path);
41 ObjectReference *old_ref() const {
42 return ObjectReference::parse(old_metadata_loc);
45 bool matched() const { return found_match; }
46 bool is_unchanged(const struct stat *stat_buf);
48 dictionary get_old_metadata() const { return old_metadata; }
49 std::list<ObjectReference> get_blocks();
50 std::string get_checksum() { return old_metadata["checksum"]; }
53 void metadata_flush();
54 void read_statcache();
56 // Where are objects eventually written to?
57 TarSegmentStore *store;
59 // File descriptors for reading/writing local statcache data
60 std::string statcache_path, statcache_tmp_path;
61 FILE *statcache_in, *statcache_out;
63 // Metadata not yet written out to the segment store
65 std::list<MetadataItem> items;
66 std::ostringstream metadata_root;
68 // Statcache information read back in from a previous run
69 bool found_match; // Result of last call to find
70 bool old_metadata_eof;
71 dictionary old_metadata;
72 std::string old_metadata_loc; // Reference to where the metadata is found
75 #endif // _LBS_METADATA_H