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