~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 */

/*

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

*/

#ifndef MYSYS_MY_ALLOC_H

#define MYSYS_MY_ALLOC_H

#include <stddef.h>

#include <drizzled/definitions.h>

#if defined(__cplusplus)

extern "C" {

#endif

#define ALLOC_MAX_BLOCK_TO_DROP			4096

#define ALLOC_MAX_BLOCK_USAGE_BEFORE_DROP	10

typedef struct st_used_mem

{				   /* struct for once_alloc (block) */

  struct st_used_mem *next;	   /* Next block in use */

  size_t left;			   /* memory left in block  */            

  size_t 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;

void init_alloc_root(MEM_ROOT *mem_root, size_t block_size,

                     size_t pre_alloc_size);

void *alloc_root(MEM_ROOT *mem_root, size_t Size);

void *multi_alloc_root(MEM_ROOT *mem_root, ...);

void free_root(MEM_ROOT *root, myf MyFLAGS);

void set_prealloc_root(MEM_ROOT *root, char *ptr);

void reset_root_defaults(MEM_ROOT *mem_root, size_t block_size,

                         size_t prealloc_size);

char *strdup_root(MEM_ROOT *root,const char *str);

char *strmake_root(MEM_ROOT *root,const char *str,size_t len);

void *memdup_root(MEM_ROOT *root,const void *str, size_t len);

#if defined(__cplusplus)

}

#endif

#endif /* MYSYS_MY_ALLOC_H */