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); |
28 | |