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         struct commit_graph *base_graph;
  68
  69         const uint32_t *chunk_oid_fanout;
  70         const unsigned char *chunk_oid_lookup;
  71         const unsigned char *chunk_commit_data;
  72         const unsigned char *chunk_generation_data;
  73         const unsigned char *chunk_generation_data_overflow;
  74         const unsigned char *chunk_extra_edges;
  75         const unsigned char *chunk_base_graphs;
  76         const unsigned char *chunk_bloom_indexes;
  77         const unsigned char *chunk_bloom_data;
  78
  79         struct topo_level_slab *topo_levels;
  80         struct bloom_filter_settings *bloom_filter_settings;
  81 };
  82
  83 struct commit_graph *load_commit_graph_one_fd_st(struct repository *r,
  84                                                  int fd, struct stat *st,
  85                                                  struct object_directory *odb);
  86 struct commit_graph *read_commit_graph_one(struct repository *r,
  87                                            struct object_directory *odb);
  88 struct commit_graph *parse_commit_graph(struct repository *r,
  89                                         void *graph_map, size_t graph_size);
  90
  91 /*
  92  * Return 1 if and only if the repository has a commit-graph
  93  * file and generation numbers are computed in that file.
  94  */
  95 int generation_numbers_enabled(struct repository *r);
  96
  97 struct bloom_filter_settings *get_bloom_filter_settings(struct repository *r);
  98
  99 enum commit_graph_write_flags {
 100         COMMIT_GRAPH_WRITE_APPEND     = (1 << 0),
 101         COMMIT_GRAPH_WRITE_PROGRESS   = (1 << 1),
 102         COMMIT_GRAPH_WRITE_SPLIT      = (1 << 2),
 103         COMMIT_GRAPH_WRITE_BLOOM_FILTERS = (1 << 3),
 104         COMMIT_GRAPH_NO_WRITE_BLOOM_FILTERS = (1 << 4),
 105 };
 106
 107 enum commit_graph_split_flags {
 108         COMMIT_GRAPH_SPLIT_UNSPECIFIED      = 0,
 109         COMMIT_GRAPH_SPLIT_MERGE_PROHIBITED = 1,
 110         COMMIT_GRAPH_SPLIT_REPLACE          = 2
 111 };
 112
 113 struct commit_graph_opts {
 114         int size_multiple;
 115         int max_commits;
 116         timestamp_t expire_time;
 117         enum commit_graph_split_flags split_flags;
 118         int max_new_filters;
 119 };
 120
 121 /*
 122  * The write_commit_graph* methods return zero on success
 123  * and a negative value on failure. Note that if the repository
 124  * is not compatible with the commit-graph feature, then the
 125  * methods will return 0 without writing a commit-graph.
 126  */
 127 int write_commit_graph_reachable(struct object_directory *odb,
 128                                  enum commit_graph_write_flags flags,
 129                                  const struct commit_graph_opts *opts);
 130 int write_commit_graph(struct object_directory *odb,
 131                        struct string_list *pack_indexes,
 132                        struct oidset *commits,
 133                        enum commit_graph_write_flags flags,
 134                        const struct commit_graph_opts *opts);
 135
 136 #define COMMIT_GRAPH_VERIFY_SHALLOW     (1 << 0)
 137
 138 int verify_commit_graph(struct repository *r, struct commit_graph *g, int flags);
 139
 140 void close_commit_graph(struct raw_object_store *);
 141 void free_commit_graph(struct commit_graph *);
 142
 143 /*
 144  * Disable further use of the commit graph in this process when parsing a
 145  * "struct commit".
 146  */
 147 void disable_commit_graph(struct repository *r);
 148
 149 struct commit_graph_data {
 150         uint32_t graph_pos;
 151         timestamp_t generation;
 152 };
 153
 154 /*
 155  * Commits should be parsed before accessing generation, graph positions.
 156  */
 157 timestamp_t commit_graph_generation(const struct commit *);
 158 uint32_t commit_graph_position(const struct commit *);
 159 #endif