merge(third_party/git): Merge squashed git subtree at v2.23.0

Merge commit '1b593e1ea4' as 'third_party/git'

third_party/git/commit-reach.h

@@ -0,0 +1,105 @@
+#ifndef COMMIT_REACH_H
+#define COMMIT_REACH_H
+
+#include "commit.h"
+#include "commit-slab.h"
+
+struct commit_list;
+struct ref_filter;
+struct object_id;
+struct object_array;
+
+struct commit_list *repo_get_merge_bases(struct repository *r,
+					 struct commit *rev1,
+					 struct commit *rev2);
+struct commit_list *repo_get_merge_bases_many(struct repository *r,
+					      struct commit *one, int n,
+					      struct commit **twos);
+/* To be used only when object flags after this call no longer matter */
+struct commit_list *repo_get_merge_bases_many_dirty(struct repository *r,
+						    struct commit *one, int n,
+						    struct commit **twos);
+#ifndef NO_THE_REPOSITORY_COMPATIBILITY_MACROS
+#define get_merge_bases(r1, r2)           repo_get_merge_bases(the_repository, r1, r2)
+#define get_merge_bases_many(one, n, two) repo_get_merge_bases_many(the_repository, one, n, two)
+#define get_merge_bases_many_dirty(one, n, twos) repo_get_merge_bases_many_dirty(the_repository, one, n, twos)
+#endif
+
+struct commit_list *get_octopus_merge_bases(struct commit_list *in);
+
+int is_descendant_of(struct commit *commit, struct commit_list *with_commit);
+int repo_in_merge_bases(struct repository *r,
+			struct commit *commit,
+			struct commit *reference);
+int repo_in_merge_bases_many(struct repository *r,
+			     struct commit *commit,
+			     int nr_reference, struct commit **reference);
+#ifndef NO_THE_REPOSITORY_COMPATIBILITY_MACROS
+#define in_merge_bases(c1, c2) repo_in_merge_bases(the_repository, c1, c2)
+#define in_merge_bases_many(c1, n, cs) repo_in_merge_bases_many(the_repository, c1, n, cs)
+#endif
+
+/*
+ * Takes a list of commits and returns a new list where those
+ * have been removed that can be reached from other commits in
+ * the list. It is useful for, e.g., reducing the commits
+ * randomly thrown at the git-merge command and removing
+ * redundant commits that the user shouldn't have given to it.
+ *
+ * This function destroys the STALE bit of the commit objects'
+ * flags.
+ */
+struct commit_list *reduce_heads(struct commit_list *heads);
+
+/*
+ * Like `reduce_heads()`, except it replaces the list. Use this
+ * instead of `foo = reduce_heads(foo);` to avoid memory leaks.
+ */
+void reduce_heads_replace(struct commit_list **heads);
+
+int ref_newer(const struct object_id *new_oid, const struct object_id *old_oid);
+
+/*
+ * Unknown has to be "0" here, because that's the default value for
+ * contains_cache slab entries that have not yet been assigned.
+ */
+enum contains_result {
+	CONTAINS_UNKNOWN = 0,
+	CONTAINS_NO,
+	CONTAINS_YES
+};
+
+define_commit_slab(contains_cache, enum contains_result);
+
+int commit_contains(struct ref_filter *filter, struct commit *commit,
+		    struct commit_list *list, struct contains_cache *cache);
+
+/*
+ * Determine if every commit in 'from' can reach at least one commit
+ * that is marked with 'with_flag'. As we traverse, use 'assign_flag'
+ * as a marker for commits that are already visited. Do not walk
+ * commits with date below 'min_commit_date' or generation below
+ * 'min_generation'.
+ */
+int can_all_from_reach_with_flag(struct object_array *from,
+				 unsigned int with_flag,
+				 unsigned int assign_flag,
+				 time_t min_commit_date,
+				 uint32_t min_generation);
+int can_all_from_reach(struct commit_list *from, struct commit_list *to,
+		       int commit_date_cutoff);
+
+
+/*
+ * Return a list of commits containing the commits in the 'to' array
+ * that are reachable from at least one commit in the 'from' array.
+ * Also add the given 'flag' to each of the commits in the returned list.
+ *
+ * This method uses the PARENT1 and PARENT2 flags during its operation,
+ * so be sure these flags are not set before calling the method.
+ */
+struct commit_list *get_reachable_subset(struct commit **from, int nr_from,
+					 struct commit **to, int nr_to,
+					 unsigned int reachable_flag);
+
+#endif