/* Copyright (c) 2000, 2010, Oracle and/or its affiliates. All rights reserved.

 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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */

/* 
 Data structures for mysys/my_alloc.c (root memory allocator)
*/

#ifndef _my_alloc_h
#define _my_alloc_h

#define ALLOC_MAX_BLOCK_TO_DROP			4096
#define ALLOC_MAX_BLOCK_USAGE_BEFORE_DROP	10

#ifdef __cplusplus
extern "C" {
#endif

typedef struct st_used_mem
{				 /* struct for once_alloc (block) */
 struct st_used_mem *next;	 /* Next block in use */
 unsigned int	left;		 /* memory left in block */
 unsigned int	size;		 /* size of block */
} USED_MEM;


typedef struct st_mem_root
{
 USED_MEM *free; /* blocks with free memory in it */
 USED_MEM *used; /* blocks almost without free memory */
 USED_MEM *pre_alloc; /* preallocated block */
 /* if block have less memory it will be put in 'used' list */
 size_t min_malloc;
 size_t block_size; /* initial block size */
 unsigned int block_num; /* allocated blocks counter */
 /* 
 first free block in queue test counter (if it exceed 
 MAX_BLOCK_USAGE_BEFORE_DROP block will be dropped in 'used' list)
 */
 unsigned int first_block_usage;

 void (*error_handler)(void);
} MEM_ROOT;

#ifdef __cplusplus
}
#endif

#endif