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