+struct refname_hash_entry {
+ struct hashmap_entry ent; /* must be the first member */
+ struct object_id oid;
+ char refname[FLEX_ARRAY];
+};
+
+static int refname_hash_entry_cmp(const void *hashmap_cmp_fn_data,
+ const void *e1_,
+ const void *e2_,
+ const void *keydata)
+{
+ const struct refname_hash_entry *e1 = e1_;
+ const struct refname_hash_entry *e2 = e2_;
+
+ return strcmp(e1->refname, keydata ? keydata : e2->refname);
+}
+
+static struct refname_hash_entry *refname_hash_add(struct hashmap *map,
+ const char *refname,
+ const struct object_id *oid)
+{
+ struct refname_hash_entry *ent;
+ size_t len = strlen(refname);
+
+ FLEX_ALLOC_MEM(ent, refname, refname, len);
+ hashmap_entry_init(ent, strhash(refname));
+ oidcpy(&ent->oid, oid);
+ hashmap_add(map, ent);
+ return ent;
+}
+
+static int add_one_refname(const char *refname,
+ const struct object_id *oid,
+ int flag, void *cbdata)
+{
+ struct hashmap *refname_map = cbdata;
+
+ (void) refname_hash_add(refname_map, refname, oid);
+ return 0;
+}
+
+static void refname_hash_init(struct hashmap *map)
+{
+ hashmap_init(map, refname_hash_entry_cmp, NULL, 0);
+}
+
+static int refname_hash_exists(struct hashmap *map, const char *refname)
+{
+ return !!hashmap_get_from_hash(map, strhash(refname), refname);
+}
+