unpack-trees: refactor prefetching code

Refactor the prefetching code in unpack-trees.c into its own function,
because it will be used elsewhere in a subsequent commit.

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 9 insertions, 0 deletions

diff --git a/cache.h b/cache.h
index ba04ff8bd3..6f952e22c6 100644
--- a/cache.h
+++ b/cache.h
@@ -410,6 +410,15 @@ struct cache_entry *dup_cache_entry(const struct cache_entry *ce, struct index_s
  */
 void validate_cache_entries(const struct index_state *istate);
 
+/*
+ * Bulk prefetch all missing cache entries that are not GITLINKs and that match
+ * the given predicate. This function should only be called if
+ * has_promisor_remote() returns true.
+ */
+typedef int (*must_prefetch_predicate)(const struct cache_entry *);
+void prefetch_cache_entries(const struct index_state *istate,
+			    must_prefetch_predicate must_prefetch);
+
 #ifdef USE_THE_INDEX_COMPATIBILITY_MACROS
 extern struct index_state the_index;