1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
|
/*
* Copyright (C) the libgit2 contributors. All rights reserved.
*
* This file is part of libgit2, distributed under the GNU GPL v2 with
* a Linking Exception. For full terms see the included COPYING file.
*/
#ifndef INCLUDE_commit_graph_h__
#define INCLUDE_commit_graph_h__
#include "common.h"
#include "map.h"
/**
* A commit-graph file.
*
* This file contains metadata about commits, particularly the generation
* number for each one. This can help speed up graph operations without
* requiring a full graph traversal.
*
* Support for this feature was added in git 2.19.
*/
typedef struct git_commit_graph_file {
git_map graph_map;
/* The OID Fanout table. */
const uint32_t *oid_fanout;
/* The total number of commits in the graph. */
uint32_t num_commits;
/* The OID Lookup table. */
git_oid *oid_lookup;
/*
* The Commit Data table. Each entry contains the OID of the commit followed
* by two 8-byte fields in network byte order:
* - The indices of the first two parents (32 bits each).
* - The generation number (first 30 bits) and commit time in seconds since
* UNIX epoch (34 bits).
*/
const unsigned char *commit_data;
/*
* The Extra Edge List table. Each 4-byte entry is a network byte order index
* of one of the i-th (i > 0) parents of commits in the `commit_data` table,
* when the commit has more than 2 parents.
*/
const unsigned char *extra_edge_list;
/* The number of entries in the Extra Edge List table. Each entry is 4 bytes wide. */
size_t num_extra_edge_list;
/* The trailer of the file. Contains the SHA1-checksum of the whole file. */
git_oid checksum;
/* something like ".git/objects/info/commit-graph". */
git_buf filename;
} git_commit_graph_file;
/**
* An entry in the commit-graph file. Provides a subset of the information that
* can be obtained from the commit header.
*/
typedef struct git_commit_graph_entry {
/* The generation number of the commit within the graph */
size_t generation;
/* Time in seconds from UNIX epoch. */
git_time_t commit_time;
/* The number of parents of the commit. */
size_t parent_count;
/*
* The indices of the parent commits within the Commit Data table. The value
* of `GIT_COMMIT_GRAPH_MISSING_PARENT` indicates that no parent is in that
* position.
*/
size_t parent_indices[2];
/* The index within the Extra Edge List of any parent after the first two. */
size_t extra_parents_index;
/* The SHA-1 hash of the root tree of the commit. */
git_oid tree_oid;
/* The SHA-1 hash of the requested commit. */
git_oid sha1;
} git_commit_graph_entry;
int git_commit_graph_open(git_commit_graph_file **cgraph_out, const char *path);
/*
* Returns whether the commit_graph_file needs to be reloaded since the
* contents of the commit-graph file have changed on disk. If `path` is NULL,
* the filename stored in `cgraph` will be used.
*/
bool git_commit_graph_needs_refresh(const git_commit_graph_file *cgraph, const char *path);
int git_commit_graph_entry_find(
git_commit_graph_entry *e,
const git_commit_graph_file *cgraph,
const git_oid *short_oid,
size_t len);
int git_commit_graph_entry_parent(
git_commit_graph_entry *parent,
const git_commit_graph_file *cgraph,
const git_commit_graph_entry *entry,
size_t n);
int git_commit_graph_close(git_commit_graph_file *cgraph);
void git_commit_graph_free(git_commit_graph_file *cgraph);
/* This is exposed for use in the fuzzers. */
int git_commit_graph_parse(git_commit_graph_file *cgraph, const unsigned char *data, size_t size);
#endif
|
