mariadb/newbrt/brt-search.h
Rich Prohaska d2d80add96 first cut or new cursors merge to trunk. addresses #250
git-svn-id: file:///svn/tokudb@1881 c7de825b-a66e-492c-adef-691d508d4ae1
2008-01-25 15:43:37 +00:00

35 lines
1.2 KiB
C

#ifndef BRT_SEARCH_H
#define BRT_SEARCH_H
enum {
BRT_SEARCH_LEFT = 1, /* search left -> right, finds min xy as defined by the compare function */
BRT_SEARCH_RIGHT = 2, /* search right -> left, finds max xy as defined by the compare function */
BRT_SEARCH_ONE = 4, /* look into only one subtree, used for point queries */
};
struct brt_search;
/* the search compare function should return 0 for all xy < kv and 1 for all xy >= kv
the compare function has liberty in implementing the semantics, but the result should
be a ramp */
typedef int (*brt_search_compare_func_t)(struct brt_search */*so*/, DBT */*x*/, DBT */*y*/);
/* the search object contains the compare function, search direction, and the kv pair that
is used in the compare function. the context is the user's private data */
typedef struct brt_search {
brt_search_compare_func_t compare;
int direction;
DBT *k;
DBT *v;
void *context;
} brt_search_t;
/* initialize the search compare object */
static inline brt_search_t *brt_search_init(brt_search_t *so, brt_search_compare_func_t compare, int direction, DBT *k, DBT *v, void *context) {
so->compare = compare; so->direction = direction; so->k = k; so->v = v; so->context = context;
return so;
}
#endif