1 files changed, 84 insertions, 0 deletions
diff --git a/notes-merge.h b/notes-merge.h
new file mode 100644
index 0000000000..1d01f6aacf
--- /dev/null
+++ b/notes-merge.h
@@ -0,0 +1,84 @@
+#ifndef NOTES_MERGE_H
+#define NOTES_MERGE_H
+
+#define NOTES_MERGE_WORKTREE "NOTES_MERGE_WORKTREE"
+
+enum notes_merge_verbosity {
+	NOTES_MERGE_VERBOSITY_DEFAULT = 2,
+	NOTES_MERGE_VERBOSITY_MAX = 5
+};
+
+struct notes_merge_options {
+	const char *local_ref;
+	const char *remote_ref;
+	struct strbuf commit_msg;
+	int verbosity;
+	enum {
+		NOTES_MERGE_RESOLVE_MANUAL = 0,
+		NOTES_MERGE_RESOLVE_OURS,
+		NOTES_MERGE_RESOLVE_THEIRS,
+		NOTES_MERGE_RESOLVE_UNION,
+		NOTES_MERGE_RESOLVE_CAT_SORT_UNIQ
+	} strategy;
+	unsigned has_worktree:1;
+};
+
+void init_notes_merge_options(struct notes_merge_options *o);
+
+/*
+ * Merge notes from o->remote_ref into o->local_ref
+ *
+ * The given notes_tree 'local_tree' must be the notes_tree referenced by the
+ * o->local_ref. This is the notes_tree in which the object-level merge is
+ * performed.
+ *
+ * The commits given by the two refs are merged, producing one of the following
+ * outcomes:
+ *
+ * 1. The merge trivially results in an existing commit (e.g. fast-forward or
+ *    already-up-to-date). 'local_tree' is untouched, the SHA1 of the result
+ *    is written into 'result_sha1' and 0 is returned.
+ * 2. The merge successfully completes, producing a merge commit. local_tree
+ *    contains the updated notes tree, the SHA1 of the resulting commit is
+ *    written into 'result_sha1', and 1 is returned.
+ * 3. The merge results in conflicts. This is similar to #2 in that the
+ *    partial merge result (i.e. merge result minus the unmerged entries)
+ *    are stored in 'local_tree', and the SHA1 or the resulting commit
+ *    (to be amended when the conflicts have been resolved) is written into
+ *    'result_sha1'. The unmerged entries are written into the
+ *    .git/NOTES_MERGE_WORKTREE directory with conflict markers.
+ *    -1 is returned.
+ *
+ * Both o->local_ref and o->remote_ref must be given (non-NULL), but either ref
+ * (although not both) may refer to a non-existing notes ref, in which case
+ * that notes ref is interpreted as an empty notes tree, and the merge
+ * trivially results in what the other ref points to.
+ */
+int notes_merge(struct notes_merge_options *o,
+		struct notes_tree *local_tree,
+		unsigned char *result_sha1);
+
+/*
+ * Finalize conflict resolution from an earlier notes_merge()
+ *
+ * The given notes tree 'partial_tree' must be the notes_tree corresponding to
+ * the given 'partial_commit', the partial result commit created by a previous
+ * call to notes_merge().
+ *
+ * This function will add the (now resolved) notes in .git/NOTES_MERGE_WORKTREE
+ * to 'partial_tree', and create a final notes merge commit, the SHA1 of which
+ * will be stored in 'result_sha1'.
+ */
+int notes_merge_commit(struct notes_merge_options *o,
+		       struct notes_tree *partial_tree,
+		       struct commit *partial_commit,
+		       unsigned char *result_sha1);
+
+/*
+ * Abort conflict resolution from an earlier notes_merge()
+ *
+ * Removes the notes merge worktree in .git/NOTES_MERGE_WORKTREE.
+ */
+int notes_merge_abort(struct notes_merge_options *o);
+
+#endif