Re: [PATCH 5/5] commit: rewrite read_graft_line

The previous implementation of read_graft_line used calculations based
on GIT_SHA1_RAWSZ and GIT_SHA1_HEXSZ to determine the number of commit
ids in a single graft line.  New implementation does not depend on these
constants, so it adapts to any object_id buffer size.

To make this possible, FLEX_ARRAY of object_id in struct was replaced
by an oid_array.

Code allocating graft now needs to use memset to zero the memory before
use to start with oid_array in a consistent state.

Updates free_graft function implemented in the previous patch to
properly cleanup an oid_array storing parents.

Signed-off-by: Patryk Obara <redacted>
---
 commit.c  | 39 +++++++++++++++++++++------------------
 commit.h  |  2 +-
 shallow.c |  1 +
 3 files changed, 23 insertions(+), 19 deletions(-)

diff --git a/commit.c b/commit.c
index 6a145f1..75dd45d 100644
--- a/commit.c
+++ b/commit.c

@@ -111,6 +111,7 @@ static int commit_graft_pos(const unsigned char *sha1)

 void free_commit_graft(struct commit_graft *graft)
 {
+       oid_array_clear(&graft->parents);