prune: save reachable-from-recent objects with bitmaps
[git] / commit-graph.h
1 #ifndef COMMIT_GRAPH_H
2 #define COMMIT_GRAPH_H
3
4 #include "git-compat-util.h"
5 #include "object-store.h"
6 #include "oidset.h"
7
8 #define GIT_TEST_COMMIT_GRAPH "GIT_TEST_COMMIT_GRAPH"
9 #define GIT_TEST_COMMIT_GRAPH_NO_GDAT "GIT_TEST_COMMIT_GRAPH_NO_GDAT"
10 #define GIT_TEST_COMMIT_GRAPH_DIE_ON_PARSE "GIT_TEST_COMMIT_GRAPH_DIE_ON_PARSE"
11 #define GIT_TEST_COMMIT_GRAPH_CHANGED_PATHS "GIT_TEST_COMMIT_GRAPH_CHANGED_PATHS"
12
13 /*
14  * This method is only used to enhance coverage of the commit-graph
15  * feature in the test suite with the GIT_TEST_COMMIT_GRAPH and
16  * GIT_TEST_COMMIT_GRAPH_CHANGED_PATHS environment variables. Do not
17  * call this method oustide of a builtin, and only if you know what
18  * you are doing!
19  */
20 void git_test_write_commit_graph_or_die(void);
21
22 struct commit;
23 struct bloom_filter_settings;
24 struct repository;
25 struct raw_object_store;
26 struct string_list;
27
28 char *get_commit_graph_filename(struct object_directory *odb);
29 char *get_commit_graph_chain_filename(struct object_directory *odb);
30 int open_commit_graph(const char *graph_file, int *fd, struct stat *st);
31
32 /*
33  * Given a commit struct, try to fill the commit struct info, including:
34  *  1. tree object
35  *  2. date
36  *  3. parents.
37  *
38  * Returns 1 if and only if the commit was found in the packed graph.
39  *
40  * See parse_commit_buffer() for the fallback after this call.
41  */
42 int parse_commit_in_graph(struct repository *r, struct commit *item);
43
44 /*
45  * It is possible that we loaded commit contents from the commit buffer,
46  * but we also want to ensure the commit-graph content is correctly
47  * checked and filled. Fill the graph_pos and generation members of
48  * the given commit.
49  */
50 void load_commit_graph_info(struct repository *r, struct commit *item);
51
52 struct tree *get_commit_tree_in_graph(struct repository *r,
53                                       const struct commit *c);
54
55 struct commit_graph {
56         const unsigned char *data;
57         size_t data_len;
58
59         unsigned char hash_len;
60         unsigned char num_chunks;
61         uint32_t num_commits;
62         struct object_id oid;
63         char *filename;
64         struct object_directory *odb;
65
66         uint32_t num_commits_in_base;
67         unsigned int read_generation_data;
68         struct commit_graph *base_graph;
69
70         const uint32_t *chunk_oid_fanout;
71         const unsigned char *chunk_oid_lookup;
72         const unsigned char *chunk_commit_data;
73         const unsigned char *chunk_generation_data;
74         const unsigned char *chunk_generation_data_overflow;
75         const unsigned char *chunk_extra_edges;
76         const unsigned char *chunk_base_graphs;
77         const unsigned char *chunk_bloom_indexes;
78         const unsigned char *chunk_bloom_data;
79
80         struct topo_level_slab *topo_levels;
81         struct bloom_filter_settings *bloom_filter_settings;
82 };
83
84 struct commit_graph *load_commit_graph_one_fd_st(struct repository *r,
85                                                  int fd, struct stat *st,
86                                                  struct object_directory *odb);
87 struct commit_graph *read_commit_graph_one(struct repository *r,
88                                            struct object_directory *odb);
89 struct commit_graph *parse_commit_graph(struct repository *r,
90                                         void *graph_map, size_t graph_size);
91
92 /*
93  * Return 1 if and only if the repository has a commit-graph
94  * file and generation numbers are computed in that file.
95  */
96 int generation_numbers_enabled(struct repository *r);
97
98 /*
99  * Return 1 if and only if the repository has a commit-graph
100  * file and generation data chunk has been written for the file.
101  */
102 int corrected_commit_dates_enabled(struct repository *r);
103
104 struct bloom_filter_settings *get_bloom_filter_settings(struct repository *r);
105
106 enum commit_graph_write_flags {
107         COMMIT_GRAPH_WRITE_APPEND     = (1 << 0),
108         COMMIT_GRAPH_WRITE_PROGRESS   = (1 << 1),
109         COMMIT_GRAPH_WRITE_SPLIT      = (1 << 2),
110         COMMIT_GRAPH_WRITE_BLOOM_FILTERS = (1 << 3),
111         COMMIT_GRAPH_NO_WRITE_BLOOM_FILTERS = (1 << 4),
112 };
113
114 enum commit_graph_split_flags {
115         COMMIT_GRAPH_SPLIT_UNSPECIFIED      = 0,
116         COMMIT_GRAPH_SPLIT_MERGE_PROHIBITED = 1,
117         COMMIT_GRAPH_SPLIT_REPLACE          = 2
118 };
119
120 struct commit_graph_opts {
121         int size_multiple;
122         int max_commits;
123         timestamp_t expire_time;
124         enum commit_graph_split_flags split_flags;
125         int max_new_filters;
126 };
127
128 /*
129  * The write_commit_graph* methods return zero on success
130  * and a negative value on failure. Note that if the repository
131  * is not compatible with the commit-graph feature, then the
132  * methods will return 0 without writing a commit-graph.
133  */
134 int write_commit_graph_reachable(struct object_directory *odb,
135                                  enum commit_graph_write_flags flags,
136                                  const struct commit_graph_opts *opts);
137 int write_commit_graph(struct object_directory *odb,
138                        struct string_list *pack_indexes,
139                        struct oidset *commits,
140                        enum commit_graph_write_flags flags,
141                        const struct commit_graph_opts *opts);
142
143 #define COMMIT_GRAPH_VERIFY_SHALLOW     (1 << 0)
144
145 int verify_commit_graph(struct repository *r, struct commit_graph *g, int flags);
146
147 void close_commit_graph(struct raw_object_store *);
148 void free_commit_graph(struct commit_graph *);
149
150 /*
151  * Disable further use of the commit graph in this process when parsing a
152  * "struct commit".
153  */
154 void disable_commit_graph(struct repository *r);
155
156 struct commit_graph_data {
157         uint32_t graph_pos;
158         timestamp_t generation;
159 };
160
161 /*
162  * Commits should be parsed before accessing generation, graph positions.
163  */
164 timestamp_t commit_graph_generation(const struct commit *);
165 uint32_t commit_graph_position(const struct commit *);
166 #endif