builtin/notes.c: Refactor creation of notes commits.

Create new function create_notes_commit() which is slightly more general than
commit_notes() (accepts multiple commit parents and does not auto-update the
notes ref). This function will be used by the notes-merge functionality in
future patches.

Also rewrite builtin/notes.c:commit_notes() to reuse this new function.

Signed-off-by: Johan Herland <johan@herland.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 27 insertions, 0 deletions

diff --git a/notes-merge.c b/notes-merge.c
index ab9885039e..b9956c3bf3 100644
--- a/notes-merge.c
+++ b/notes-merge.c
@@ -1,6 +1,7 @@
 #include "cache.h"
 #include "commit.h"
 #include "refs.h"
+#include "notes.h"
 #include "notes-merge.h"
 
 void init_notes_merge_options(struct notes_merge_options *o)
@@ -17,6 +18,32 @@ void init_notes_merge_options(struct notes_merge_options *o)
 		} \
 	} while (0)
 
+void create_notes_commit(struct notes_tree *t, struct commit_list *parents,
+			 const char *msg, unsigned char *result_sha1)
+{
+	unsigned char tree_sha1[20];
+
+	assert(t->initialized);
+
+	if (write_notes_tree(t, tree_sha1))
+		die("Failed to write notes tree to database");
+
+	if (!parents) {
+		/* Deduce parent commit from t->ref */
+		unsigned char parent_sha1[20];
+		if (!read_ref(t->ref, parent_sha1)) {
+			struct commit *parent = lookup_commit(parent_sha1);
+			if (!parent || parse_commit(parent))
+				die("Failed to find/parse commit %s", t->ref);
+			commit_list_insert(parent, &parents);
+		}
+		/* else: t->ref points to nothing, assume root/orphan commit */
+	}
+
+	if (commit_tree(msg, tree_sha1, parents, result_sha1, NULL))
+		die("Failed to commit notes tree to database");
+}
+
 int notes_merge(struct notes_merge_options *o,
 		unsigned char *result_sha1)
 {