ref-filter: factor ref_array pushing into its own function

In preparation for callers constructing their own ref_array
structs, let's move our own internal push operation into its
own function.

While we're at it, we can replace REALLOC_ARRAY() with
ALLOC_GROW(), which should give the growth operation
amortized linear complexity (as opposed to growing by one,
which is potentially quadratic, though in-place realloc
growth often makes this faster in practice).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 8 insertions, 0 deletions

diff --git a/ref-filter.h b/ref-filter.h
index 68268f9..76cf87c 100644
--- a/ref-filter.h
+++ b/ref-filter.h
@@ -135,4 +135,12 @@ void setup_ref_filter_porcelain_msg(void);
 void pretty_print_ref(const char *name, const struct object_id *oid,
 		      const struct ref_format *format);
 
+/*
+ * Push a single ref onto the array; this can be used to construct your own
+ * ref_array without using filter_refs().
+ */
+struct ref_array_item *ref_array_push(struct ref_array *array,
+				      const char *refname,
+				      const struct object_id *oid);
+
 #endif /*  REF_FILTER_H  */