~drizzle-trunk/drizzle/development

1 by brian
clean slate
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/* Copyright (C) 2000 MySQL AB
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   This program is free software; you can redistribute it and/or modify
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   it under the terms of the GNU General Public License as published by
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   the Free Software Foundation; version 2 of the License.
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   This program is distributed in the hope that it will be useful,
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   but WITHOUT ANY WARRANTY; without even the implied warranty of
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   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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   GNU General Public License for more details.
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   You should have received a copy of the GNU General Public License
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   along with this program; if not, write to the Free Software
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   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */
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/* Dynamic hashing of record with different key-length */
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#ifndef _hash_h
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#define _hash_h
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#ifdef	__cplusplus
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extern "C" {
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#endif
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/*
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  Overhead to store an element in hash
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  Can be used to approximate memory consumption for a hash
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 */
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#define HASH_OVERHEAD (sizeof(char*)*2)
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/* flags for hash_init */
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#define HASH_UNIQUE     1       /* hash_insert fails on duplicate key */
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typedef uchar *(*hash_get_key)(const uchar *,size_t*,my_bool);
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typedef void (*hash_free_key)(void *);
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typedef struct st_hash {
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  size_t key_offset,key_length;		/* Length of key if const length */
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  size_t blength;
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  ulong records;
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  uint flags;
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  DYNAMIC_ARRAY array;				/* Place for hash_keys */
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  hash_get_key get_key;
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  void (*free)(void *);
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  CHARSET_INFO *charset;
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} HASH;
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/* A search iterator state */
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typedef uint HASH_SEARCH_STATE;
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#define hash_init(A,B,C,D,E,F,G,H) _hash_init(A,0,B,C,D,E,F,G,H CALLER_INFO)
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#define hash_init2(A,B,C,D,E,F,G,H,I) _hash_init(A,B,C,D,E,F,G,H,I CALLER_INFO)
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my_bool _hash_init(HASH *hash, uint growth_size,CHARSET_INFO *charset,
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		   ulong default_array_elements, size_t key_offset,
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		   size_t key_length, hash_get_key get_key,
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		   void (*free_element)(void*), uint flags CALLER_INFO_PROTO);
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void hash_free(HASH *tree);
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void my_hash_reset(HASH *hash);
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uchar *hash_element(HASH *hash,ulong idx);
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uchar *hash_search(const HASH *info, const uchar *key, size_t length);
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uchar *hash_first(const HASH *info, const uchar *key, size_t length,
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                HASH_SEARCH_STATE *state);
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uchar *hash_next(const HASH *info, const uchar *key, size_t length,
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                 HASH_SEARCH_STATE *state);
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my_bool my_hash_insert(HASH *info,const uchar *data);
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my_bool hash_delete(HASH *hash,uchar *record);
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my_bool hash_update(HASH *hash,uchar *record,uchar *old_key,size_t old_key_length);
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void hash_replace(HASH *hash, HASH_SEARCH_STATE *state, uchar *new_row);
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my_bool hash_check(HASH *hash);			/* Only in debug library */
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#define hash_clear(H) bzero((char*) (H),sizeof(*(H)))
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#define hash_inited(H) ((H)->array.buffer != 0)
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#define hash_init_opt(A,B,C,D,E,F,G,H) \
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          (!hash_inited(A) && _hash_init(A,0,B,C,D,E,F,G, H CALLER_INFO))
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#ifdef	__cplusplus
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}
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#endif
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#endif