1 files changed, 111 insertions, 0 deletions
diff --git a/heap/hp_block.c b/heap/hp_block.c
new file mode 100644
index 00000000000..510d89d6d1e
--- /dev/null
+++ b/heap/hp_block.c
@@ -0,0 +1,111 @@
+/* Copyright (C) 2000 MySQL AB & MySQL Finland AB & TCX DataKonsult 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; either version 2 of the License, or
+   (at your option) any later version.
+   
+   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 */
+
+/* functions on blocks; Keys and records are saved in blocks */
+
+#include "heapdef.h"
+
+	/* Find record according to record-position */
+
+byte *_hp_find_block(HP_BLOCK *block, ulong pos)
+{
+  reg1 int i;
+  reg3 HP_PTRS *ptr;
+
+  for (i=block->levels-1, ptr=block->root ; i > 0 ; i--)
+  {
+    ptr=(HP_PTRS*)ptr->blocks[pos/block->level_info[i].records_under_level];
+    pos%=block->level_info[i].records_under_level;
+  }
+  return (byte*) ptr+ pos*block->recbuffer;
+}
+
+
+	/* get one new block-of-records. Alloc ptr to block if neaded */
+	/* Interrupts are stopped to allow ha_panic in interrupts */
+
+int _hp_get_new_block(HP_BLOCK *block, ulong *alloc_length)
+{
+  reg1 uint i,j;
+  HP_PTRS *root;
+
+  for (i=0 ; i < block->levels ; i++)
+    if (block->level_info[i].free_ptrs_in_block)
+      break;
+
+  *alloc_length=sizeof(HP_PTRS)*i+block->records_in_block* block->recbuffer;
+  if (!(root=(HP_PTRS*) my_malloc(*alloc_length,MYF(0))))
+    return 1;
+
+  if (i == 0)
+  {
+    block->levels=1;
+    block->root=block->level_info[0].last_blocks=root;
+  }
+  else
+  {
+    dont_break();		/* Dont allow SIGHUP or SIGINT */
+    if ((uint) i == block->levels)
+    {
+      block->levels=i+1;
+      block->level_info[i].free_ptrs_in_block=HP_PTRS_IN_NOD-1;
+      ((HP_PTRS**) root)[0]= block->root;
+      block->root=block->level_info[i].last_blocks= root++;
+    }
+    block->level_info[i].last_blocks->
+      blocks[HP_PTRS_IN_NOD - block->level_info[i].free_ptrs_in_block--]=
+	(byte*) root;
+
+    for (j=i-1 ; j >0 ; j--)
+    {
+      block->level_info[j].last_blocks= root++;
+      block->level_info[j].last_blocks->blocks[0]=(byte*) root;
+      block->level_info[j].free_ptrs_in_block=HP_PTRS_IN_NOD-1;
+    }
+    block->level_info[0].last_blocks= root;
+    allow_break();		/* Allow SIGHUP & SIGINT */
+  }
+  return 0;
+}
+
+
+	/* free all blocks under level */
+
+byte *_hp_free_level(HP_BLOCK *block, uint level, HP_PTRS *pos, byte *last_pos)
+{
+  int i,max_pos;
+  byte *next_ptr;
+
+  if (level == 1)
+    next_ptr=(byte*) pos+block->recbuffer;
+  else
+  {
+    max_pos= (block->level_info[level-1].last_blocks == pos) ?
+      HP_PTRS_IN_NOD - block->level_info[level-1].free_ptrs_in_block :
+    HP_PTRS_IN_NOD;
+
+    next_ptr=(byte*) (pos+1);
+    for (i=0 ; i < max_pos ; i++)
+      next_ptr=_hp_free_level(block,level-1,
+			      (HP_PTRS*) pos->blocks[i],next_ptr);
+  }
+  if ((byte*) pos != last_pos)
+  {
+    my_free((gptr) pos,MYF(0));
+    return last_pos;
+  }
+  return next_ptr;			/* next memory position */
+}