odb: allow asking for the size alonecmn/read-only-size

Reading a packed object's type can be expensive if it's deeply
chained. Allow a caller to skip that part of the lookup if they don't
care or know the type through other means.

1 files changed, 7 insertions, 0 deletions

diff --git a/src/pack.c b/src/pack.c
index e7003e66d..0578d852e 100644
--- a/src/pack.c
+++ b/src/pack.c
@@ -513,6 +513,13 @@ int git_packfile_resolve_header(
 	} else
 		*size_p = size;
 
+	/*
+	 * If the caller isn't interested in the type, we can return
+	 * now instead of trying to resolve the deltas.
+	 */
+	if (type_p == NULL)
+		return 0;
+
 	while (type == GIT_OBJ_OFS_DELTA || type == GIT_OBJ_REF_DELTA) {
 		curpos = base_offset;
 		error = git_packfile_unpack_header(&size, &type, &p->mwf, &w_curs, &curpos);