+/* The reference held by the hash table does not count towards the reference
+ * count. When a new object is created, it initially has a reference count of
+ * 1 for the creator, and similarly fetching an item from the hash table will
+ * also create a reference. If the reference count drops to zero,
+ * bluesky_cloudlog_unref attempts to remove the object from the hash
+ * table--but there is a potential race since another thread might read the
+ * object from the hash table at the same time. So an object with a reference
+ * count of zero may still be resurrected, in which case we need to abort the
+ * destruction. Once the object is gone from the hash table, and if the
+ * reference count is still zero, it can actually be deleted. */