commit-reach.h

   1 #ifndef COMMIT_REACH_H
   2 #define COMMIT_REACH_H
   3
   4 #include "commit.h"
   5 #include "commit-slab.h"
   6
   7 struct commit_list;
   8 struct ref_filter;
   9 struct object_id;
  10 struct object_array;
  11
  12 int repo_get_merge_bases(struct repository *r,
  13                          struct commit *rev1,
  14                          struct commit *rev2,
  15                          struct commit_list **result);
  16 int repo_get_merge_bases_many(struct repository *r,
  17                               struct commit *one, int n,
  18                               struct commit **twos,
  19                               struct commit_list **result);
  20 /* To be used only when object flags after this call no longer matter */
  21 int repo_get_merge_bases_many_dirty(struct repository *r,
  22                                     struct commit *one, int n,
  23                                     struct commit **twos,
  24                                     struct commit_list **result);
  25
  26 int get_octopus_merge_bases(struct commit_list *in, struct commit_list **result);
  27
  28 int repo_is_descendant_of(struct repository *r,
  29                           struct commit *commit,
  30                           struct commit_list *with_commit);
  31 int repo_in_merge_bases(struct repository *r,
  32                         struct commit *commit,
  33                         struct commit *reference);
  34 int repo_in_merge_bases_many(struct repository *r,
  35                              struct commit *commit,
  36                              int nr_reference, struct commit **reference,
  37                              int ignore_missing_commits);
  38
  39 /*
  40  * Takes a list of commits and returns a new list where those
  41  * have been removed that can be reached from other commits in
  42  * the list. It is useful for, e.g., reducing the commits
  43  * randomly thrown at the git-merge command and removing
  44  * redundant commits that the user shouldn't have given to it.
  45  *
  46  * This function destroys the STALE bit of the commit objects'
  47  * flags.
  48  */
  49 struct commit_list *reduce_heads(struct commit_list *heads);
  50
  51 /*
  52  * Like `reduce_heads()`, except it replaces the list. Use this
  53  * instead of `foo = reduce_heads(foo);` to avoid memory leaks.
  54  */
  55 void reduce_heads_replace(struct commit_list **heads);
  56
  57 int ref_newer(const struct object_id *new_oid, const struct object_id *old_oid);
  58
  59 /*
  60  * Unknown has to be "0" here, because that's the default value for
  61  * contains_cache slab entries that have not yet been assigned.
  62  */
  63 enum contains_result {
  64         CONTAINS_UNKNOWN = 0,
  65         CONTAINS_NO,
  66         CONTAINS_YES
  67 };
  68
  69 define_commit_slab(contains_cache, enum contains_result);
  70
  71 int commit_contains(struct ref_filter *filter, struct commit *commit,
  72                     struct commit_list *list, struct contains_cache *cache);
  73
  74 /*
  75  * Determine if every commit in 'from' can reach at least one commit
  76  * that is marked with 'with_flag'. As we traverse, use 'assign_flag'
  77  * as a marker for commits that are already visited. Do not walk
  78  * commits with date below 'min_commit_date' or generation below
  79  * 'min_generation'.
  80  */
  81 int can_all_from_reach_with_flag(struct object_array *from,
  82                                  unsigned int with_flag,
  83                                  unsigned int assign_flag,
  84                                  time_t min_commit_date,
  85                                  timestamp_t min_generation);
  86 int can_all_from_reach(struct commit_list *from, struct commit_list *to,
  87                        int commit_date_cutoff);
  88
  89
  90 /*
  91  * Return a list of commits containing the commits in the 'to' array
  92  * that are reachable from at least one commit in the 'from' array.
  93  * Also add the given 'flag' to each of the commits in the returned list.
  94  *
  95  * This method uses the PARENT1 and PARENT2 flags during its operation,
  96  * so be sure these flags are not set before calling the method.
  97  */
  98 struct commit_list *get_reachable_subset(struct commit **from, int nr_from,
  99                                          struct commit **to, int nr_to,
 100                                          unsigned int reachable_flag);
 101
 102 struct ahead_behind_count {
 103         /**
 104          * As input, the *_index members indicate which positions in
 105          * the 'tips' array correspond to the tip and base of this
 106          * comparison.
 107          */
 108         size_t tip_index;
 109         size_t base_index;
 110
 111         /**
 112          * These values store the computed counts for each side of the
 113          * symmetric difference:
 114          *
 115          * 'ahead' stores the number of commits reachable from the tip
 116          * and not reachable from the base.
 117          *
 118          * 'behind' stores the number of commits reachable from the base
 119          * and not reachable from the tip.
 120          */
 121         unsigned int ahead;
 122         unsigned int behind;
 123 };
 124
 125 /*
 126  * Given an array of commits and an array of ahead_behind_count pairs,
 127  * compute the ahead/behind counts for each pair.
 128  */
 129 void ahead_behind(struct repository *r,
 130                   struct commit **commits, size_t commits_nr,
 131                   struct ahead_behind_count *counts, size_t counts_nr);
 132
 133 /*
 134  * For all tip commits, add 'mark' to their flags if and only if they
 135  * are reachable from one of the commits in 'bases'.
 136  */
 137 void tips_reachable_from_bases(struct repository *r,
 138                                struct commit_list *bases,
 139                                struct commit **tips, size_t tips_nr,
 140                                int mark);
 141
 142 /*
 143  * Given a 'tip' commit and a list potential 'bases', return the index 'i' that
 144  * minimizes the number of commits in the first-parent history of 'tip' and not
 145  * in the first-parent history of 'bases[i]'.
 146  *
 147  * Among a list of long-lived branches that are updated only by merges (with the
 148  * first parent being the previous position of the branch), this would inform
 149  * which branch was used to create the tip reference.
 150  *
 151  * Returns -1 if no common point is found in first-parent histories, which is
 152  * rare, but possible with multiple root commits.
 153  */
 154 int get_branch_base_for_tip(struct repository *r,
 155                             struct commit *tip,
 156                             struct commit **bases,
 157                             size_t bases_nr);
 158
 159 #endif