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	 eab2893dac
			
		
	
	eab2893dac
	
	
	
		
			
			Renamed _hp_func -> hp_func mi_key_cmp moved to /mysys/my_handler.c New tests for HEAP tables
		
			
				
	
	
		
			112 lines
		
	
	
		
			3.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			112 lines
		
	
	
		
			3.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* Copyright (C) 2000 MySQL AB & MySQL Finland AB & TCX DataKonsult AB
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| 
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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; either version 2 of the License, or
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|    (at your option) any later version.
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| 
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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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| 
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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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| 
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| /* functions on blocks; Keys and records are saved in blocks */
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| 
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| #include "heapdef.h"
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| 
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| 	/* Find record according to record-position */
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| 
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| byte *hp_find_block(HP_BLOCK *block, ulong pos)
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| {
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|   reg1 int i;
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|   reg3 HP_PTRS *ptr;
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| 
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|   for (i=block->levels-1, ptr=block->root ; i > 0 ; i--)
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|   {
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|     ptr=(HP_PTRS*)ptr->blocks[pos/block->level_info[i].records_under_level];
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|     pos%=block->level_info[i].records_under_level;
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|   }
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|   return (byte*) ptr+ pos*block->recbuffer;
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| }
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| 
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| 
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| 	/* get one new block-of-records. Alloc ptr to block if neaded */
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| 	/* Interrupts are stopped to allow ha_panic in interrupts */
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| 
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| int hp_get_new_block(HP_BLOCK *block, ulong *alloc_length)
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| {
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|   reg1 uint i,j;
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|   HP_PTRS *root;
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| 
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|   for (i=0 ; i < block->levels ; i++)
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|     if (block->level_info[i].free_ptrs_in_block)
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|       break;
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| 
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|   *alloc_length=sizeof(HP_PTRS)*i+block->records_in_block* block->recbuffer;
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|   if (!(root=(HP_PTRS*) my_malloc(*alloc_length,MYF(0))))
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|     return 1;
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| 
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|   if (i == 0)
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|   {
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|     block->levels=1;
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|     block->root=block->level_info[0].last_blocks=root;
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|   }
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|   else
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|   {
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|     dont_break();		/* Dont allow SIGHUP or SIGINT */
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|     if ((uint) i == block->levels)
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|     {
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|       block->levels=i+1;
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|       block->level_info[i].free_ptrs_in_block=HP_PTRS_IN_NOD-1;
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|       ((HP_PTRS**) root)[0]= block->root;
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|       block->root=block->level_info[i].last_blocks= root++;
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|     }
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|     block->level_info[i].last_blocks->
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|       blocks[HP_PTRS_IN_NOD - block->level_info[i].free_ptrs_in_block--]=
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| 	(byte*) root;
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| 
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|     for (j=i-1 ; j >0 ; j--)
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|     {
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|       block->level_info[j].last_blocks= root++;
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|       block->level_info[j].last_blocks->blocks[0]=(byte*) root;
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|       block->level_info[j].free_ptrs_in_block=HP_PTRS_IN_NOD-1;
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|     }
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|     block->level_info[0].last_blocks= root;
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|     allow_break();		/* Allow SIGHUP & SIGINT */
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|   }
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|   return 0;
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| }
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| 
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| 
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| 	/* free all blocks under level */
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| 
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| byte *hp_free_level(HP_BLOCK *block, uint level, HP_PTRS *pos, byte *last_pos)
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| {
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|   int i,max_pos;
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|   byte *next_ptr;
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| 
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|   if (level == 1)
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|     next_ptr=(byte*) pos+block->recbuffer;
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|   else
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|   {
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|     max_pos= (block->level_info[level-1].last_blocks == pos) ?
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|       HP_PTRS_IN_NOD - block->level_info[level-1].free_ptrs_in_block :
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|     HP_PTRS_IN_NOD;
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| 
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|     next_ptr=(byte*) (pos+1);
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|     for (i=0 ; i < max_pos ; i++)
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|       next_ptr=hp_free_level(block,level-1,
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| 			      (HP_PTRS*) pos->blocks[i],next_ptr);
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|   }
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|   if ((byte*) pos != last_pos)
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|   {
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|     my_free((gptr) pos,MYF(0));
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|     return last_pos;
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|   }
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|   return next_ptr;			/* next memory position */
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| }
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