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