func CNodePrev(db *C.ol_database, key string, klen uintptr) *C.ol_splay_tree_node {
var _key string
var _klen uintptr
bucket := CGetBucket(db, key, klen, &_key, &_klen)
if bucket == nil {
return nil
}
node := bucket.node
minimum := C.ols_subtree_minimum(db.tree.root)
ret := int(C._olc_prev(&node, minimum))
if ret == 0 || node == bucket.node {
return nil
}
return node
}
func CNodeFirst(db *C.ol_database) *C.ol_splay_tree_node {
minimum := C.ols_subtree_minimum(db.tree.root)
return minimum
}