Modules/rotatingtree.h

   1 /* "Rotating trees" (Armin Rigo)
   2  *
   3  * Google "splay trees" for the general idea.
   4  *
   5  * It's a dict-like data structure that works best when accesses are not
   6  * random, but follow a strong pattern.  The one implemented here is for
   7  * access patterns where the same small set of keys is looked up over
   8  * and over again, and this set of keys evolves slowly over time.
   9  */
  10
  11 #include <stdlib.h>
  12
  13 #define EMPTY_ROTATING_TREE       ((rotating_node_t *)NULL)
  14
  15 typedef struct rotating_node_s rotating_node_t;
  16 typedef int (*rotating_tree_enum_fn) (rotating_node_t *node, void *arg);
  17
  18 struct rotating_node_s {
  19         void *key;
  20         rotating_node_t *left;
  21         rotating_node_t *right;
  22 };
  23
  24 void RotatingTree_Add(rotating_node_t **root, rotating_node_t *node);
  25 rotating_node_t* RotatingTree_Get(rotating_node_t **root, void *key);
  26 int RotatingTree_Enum(rotating_node_t *root, rotating_tree_enum_fn enumfn,
  27                       void *arg);