commit: make 'commit_graft_pos' non-static

In the next patch, some functions will be moved from 'commit.c' to have
prototypes in a new 'shallow.h' and their implementations in
'shallow.c'.

Three functions in 'commit.c' use 'commit_graft_pos()' (they are
'register_commit_graft()', 'lookup_commit_graft()', and
'unregister_shallow()'). The first two of these will stay in 'commit.c',
but the latter will move to 'shallow.c', and thus needs
'commit_graft_pos' to be non-static.

Prepare for that by making 'commit_graft_pos' non-static so that it can
be called from both 'commit.c' and 'shallow.c'.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

commit.c

@@ -110,7 +110,7 @@ static const unsigned char *commit_graft_sha1_access(size_t index, void *table)
 	return commit_graft_table[index]->oid.hash;
 }
 
-static int commit_graft_pos(struct repository *r, const unsigned char *sha1)
+int commit_graft_pos(struct repository *r, const unsigned char *sha1)
 {
 	return sha1_pos(sha1, r->parsed_objects->grafts,
 			r->parsed_objects->grafts_nr,

commit.h

@@ -236,6 +236,8 @@ struct commit_graft {
 typedef int (*each_commit_graft_fn)(const struct commit_graft *, void *);
 
 struct commit_graft *read_graft_line(struct strbuf *line);
+/* commit_graft_pos returns an index into r->parsed_objects->grafts. */
+int commit_graft_pos(struct repository *r, const unsigned char *sha1);
 int register_commit_graft(struct repository *r, struct commit_graft *, int);
 void prepare_commit_graft(struct repository *r);
 struct commit_graft *lookup_commit_graft(struct repository *r, const struct object_id *oid);