builtin/commit-graph.c: introduce split strategy 'replace'
[git] / commit-graph.h
1 #ifndef COMMIT_GRAPH_H
2 #define COMMIT_GRAPH_H
3
4 #include "git-compat-util.h"
5 #include "repository.h"
6 #include "string-list.h"
7 #include "cache.h"
8 #include "object-store.h"
9
10 #define GIT_TEST_COMMIT_GRAPH "GIT_TEST_COMMIT_GRAPH"
11 #define GIT_TEST_COMMIT_GRAPH_DIE_ON_LOAD "GIT_TEST_COMMIT_GRAPH_DIE_ON_LOAD"
12
13 struct commit;
14
15 char *get_commit_graph_filename(struct object_directory *odb);
16 int open_commit_graph(const char *graph_file, int *fd, struct stat *st);
17
18 /*
19  * Given a commit struct, try to fill the commit struct info, including:
20  *  1. tree object
21  *  2. date
22  *  3. parents.
23  *
24  * Returns 1 if and only if the commit was found in the packed graph.
25  *
26  * See parse_commit_buffer() for the fallback after this call.
27  */
28 int parse_commit_in_graph(struct repository *r, struct commit *item);
29
30 /*
31  * It is possible that we loaded commit contents from the commit buffer,
32  * but we also want to ensure the commit-graph content is correctly
33  * checked and filled. Fill the graph_pos and generation members of
34  * the given commit.
35  */
36 void load_commit_graph_info(struct repository *r, struct commit *item);
37
38 struct tree *get_commit_tree_in_graph(struct repository *r,
39                                       const struct commit *c);
40
41 struct commit_graph {
42         int graph_fd;
43
44         const unsigned char *data;
45         size_t data_len;
46
47         unsigned char hash_len;
48         unsigned char num_chunks;
49         uint32_t num_commits;
50         struct object_id oid;
51         char *filename;
52         struct object_directory *odb;
53
54         uint32_t num_commits_in_base;
55         struct commit_graph *base_graph;
56
57         const uint32_t *chunk_oid_fanout;
58         const unsigned char *chunk_oid_lookup;
59         const unsigned char *chunk_commit_data;
60         const unsigned char *chunk_extra_edges;
61         const unsigned char *chunk_base_graphs;
62 };
63
64 struct commit_graph *load_commit_graph_one_fd_st(int fd, struct stat *st,
65                                                  struct object_directory *odb);
66 struct commit_graph *read_commit_graph_one(struct repository *r,
67                                            struct object_directory *odb);
68 struct commit_graph *parse_commit_graph(void *graph_map, int fd,
69                                         size_t graph_size);
70
71 /*
72  * Return 1 if and only if the repository has a commit-graph
73  * file and generation numbers are computed in that file.
74  */
75 int generation_numbers_enabled(struct repository *r);
76
77 enum commit_graph_write_flags {
78         COMMIT_GRAPH_WRITE_APPEND     = (1 << 0),
79         COMMIT_GRAPH_WRITE_PROGRESS   = (1 << 1),
80         COMMIT_GRAPH_WRITE_SPLIT      = (1 << 2),
81         /* Make sure that each OID in the input is a valid commit OID. */
82         COMMIT_GRAPH_WRITE_CHECK_OIDS = (1 << 3)
83 };
84
85 enum commit_graph_split_flags {
86         COMMIT_GRAPH_SPLIT_UNSPECIFIED      = 0,
87         COMMIT_GRAPH_SPLIT_MERGE_PROHIBITED = 1,
88         COMMIT_GRAPH_SPLIT_REPLACE          = 2
89 };
90
91 struct split_commit_graph_opts {
92         int size_multiple;
93         int max_commits;
94         timestamp_t expire_time;
95         enum commit_graph_split_flags flags;
96 };
97
98 /*
99  * The write_commit_graph* methods return zero on success
100  * and a negative value on failure. Note that if the repository
101  * is not compatible with the commit-graph feature, then the
102  * methods will return 0 without writing a commit-graph.
103  */
104 int write_commit_graph_reachable(struct object_directory *odb,
105                                  enum commit_graph_write_flags flags,
106                                  const struct split_commit_graph_opts *split_opts);
107 int write_commit_graph(struct object_directory *odb,
108                        struct string_list *pack_indexes,
109                        struct string_list *commit_hex,
110                        enum commit_graph_write_flags flags,
111                        const struct split_commit_graph_opts *split_opts);
112
113 #define COMMIT_GRAPH_VERIFY_SHALLOW     (1 << 0)
114
115 int verify_commit_graph(struct repository *r, struct commit_graph *g, int flags);
116
117 void close_commit_graph(struct raw_object_store *);
118 void free_commit_graph(struct commit_graph *);
119
120 /*
121  * Disable further use of the commit graph in this process when parsing a
122  * "struct commit".
123  */
124 void disable_commit_graph(struct repository *r);
125
126 #endif