[PATCH v5 02/19] fsck.h: use designed initializers for FSCK_OPTIONS_{DEFAULT,STRICT}

Refactor the definitions of FSCK_OPTIONS_{DEFAULT,STRICT} to use
designated initializers.

While I'm at it add the "object_names" member to the
initialization. This was omitted in 7b35efd734e (fsck_walk():
optionally name objects on the go, 2016-07-17) when the field was
added.

I'm using a new FSCK_OPTIONS_COMMON and FSCK_OPTIONS_COMMON_ERROR_FUNC
helper macros to define what FSCK_OPTIONS_{DEFAULT,STRICT} have in
common, and define the two in terms of those macro.

The FSCK_OPTIONS_COMMON macro will be used in a subsequent commit to
define other variants of common fsck initialization that wants to use
a custom error function, but share the rest of the defaults.

Signed-off-by: Ævar Arnfjörð Bjarmason <redacted>
---
 fsck.h | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/fsck.h b/fsck.h
index f70d11c559..15e12f292f 100644
--- a/fsck.h
+++ b/fsck.h

@@ -43,8 +43,17 @@ struct fsck_options {
 	kh_oid_map_t *object_names;
 };
 
-#define FSCK_OPTIONS_DEFAULT { NULL, fsck_error_function, 0, NULL, OIDSET_INIT }
-#define FSCK_OPTIONS_STRICT { NULL, fsck_error_function, 1, NULL, OIDSET_INIT }
+#define FSCK_OPTIONS_COMMON \
+	.walk = NULL, \
+	.msg_type = NULL, \
+	.skiplist = OIDSET_INIT, \
+	.object_names = NULL,
+#define FSCK_OPTIONS_COMMON_ERROR_FUNC \
+	FSCK_OPTIONS_COMMON \
+	.error_func = fsck_error_function
+
+#define FSCK_OPTIONS_DEFAULT	{ .strict = 0, FSCK_OPTIONS_COMMON_ERROR_FUNC }
+#define FSCK_OPTIONS_STRICT	{ .strict = 1, FSCK_OPTIONS_COMMON_ERROR_FUNC }
 
 /* descend in all linked child objects
  * the return value is:

-- 
2.31.0.260.g719c683c1d