~drizzle-trunk/drizzle/development

/* Copyright (C) 2000 MySQL AB

   This program is free software; you can redistribute it and/or modify

   it under the terms of the GNU General Public License as published by

   the Free Software Foundation; version 2 of the License.

   This program is distributed in the hope that it will be useful,

   but WITHOUT ANY WARRANTY; without even the implied warranty of

   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License

   along with this program; if not, write to the Free Software

   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */

#ifndef DRIZZLED_MY_TREE_H

#define DRIZZLED_MY_TREE_H

#include <unistd.h>

#include "drizzled/base.h"		/* get 'enum ha_rkey_function' */

#include "drizzled/qsort_cmp.h"

#include "drizzled/memory/root.h"

namespace drizzled

{

/* Worst case tree is half full. This gives use 2^(MAX_TREE_HEIGHT/2) leafs */

static const int MAX_TREE_HEIGHT= 64;

static const int TREE_NO_DUPS= 1;

typedef enum { left_root_right, right_root_left } TREE_WALK;

typedef int (*tree_walk_action)(void *,uint32_t,void *);

typedef enum { free_init, free_free, free_end } TREE_FREE;

typedef void (*tree_element_free)(void*, TREE_FREE, void *);

typedef struct st_tree_element {

  struct st_tree_element *left,*right;

  uint32_t count:31,

	 colour:1;			/* black is marked as 1 */

} TREE_ELEMENT;

static const int TREE_ELEMENT_EXTRA_SIZE= (sizeof(TREE_ELEMENT) + sizeof(void*));

typedef struct st_tree {

  TREE_ELEMENT *root,null_element;

  TREE_ELEMENT **parents[MAX_TREE_HEIGHT];

  uint32_t offset_to_key, elements_in_tree, size_of_element;

  size_t memory_limit;

  size_t allocated;

  qsort_cmp2 compare;

  void *custom_arg;

  memory::Root mem_root;

  bool with_delete;

  tree_element_free free;

  uint32_t flag;

} TREE;

/* Functions on whole tree */

void init_tree(TREE *tree, size_t default_alloc_size, uint32_t memory_limit,

               uint32_t size, qsort_cmp2 compare, bool with_delete,

	       tree_element_free free_element, void *custom_arg);

void delete_tree(TREE*);

void reset_tree(TREE*);

/* 

  similar to delete tree, except we do not free() blocks in mem_root

*/

#define is_tree_inited(tree) ((tree)->root != 0)

/* Functions on leafs */

TREE_ELEMENT *tree_insert(TREE *tree,void *key, uint32_t key_size,

                          void *custom_arg);

int tree_walk(TREE *tree,tree_walk_action action,

	      void *argument, TREE_WALK visit);

int tree_delete(TREE *tree, void *key, uint32_t key_size, void *custom_arg);

void *tree_search_key(TREE *tree, const void *key,

                      TREE_ELEMENT **parents, TREE_ELEMENT ***last_pos,

                      enum ha_rkey_function flag, void *custom_arg);

void *tree_search_edge(TREE *tree, TREE_ELEMENT **parents,

                        TREE_ELEMENT ***last_pos, int child_offs);

void *tree_search_next(TREE *tree, TREE_ELEMENT ***last_pos, int l_offs,

                       int r_offs);

ha_rows tree_record_pos(TREE *tree, const void *key,

                        enum ha_rkey_function search_flag, void *custom_arg);

} /* namespace drizzled */

#endif /* DRIZZLED_MY_TREE_H */