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-rw-r--r--heap/hp_open.c173
1 files changed, 173 insertions, 0 deletions
diff --git a/heap/hp_open.c b/heap/hp_open.c
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index 00000000000..77de5ca824a
--- /dev/null
+++ b/heap/hp_open.c
@@ -0,0 +1,173 @@
+/* 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 */
+
+/* open a heap-database */
+
+#include "heapdef.h"
+#ifdef VMS
+#include "hp_static.c" /* Stupid vms-linker */
+#endif
+
+static void init_block(HP_BLOCK *block,uint reclength,ulong min_records,
+ ulong max_records);
+
+ /* open a heap database. */
+
+HP_INFO *heap_open(const char *name, int mode, uint keys, HP_KEYDEF *keydef,
+ uint reclength, ulong max_records, ulong min_records)
+{
+ uint i,j,key_segs,max_length,length;
+ HP_INFO *info;
+ HP_SHARE *share;
+ HP_KEYSEG *keyseg;
+ DBUG_ENTER("heap_open");
+
+ pthread_mutex_lock(&THR_LOCK_heap);
+ if (!(share=_hp_find_named_heap(name)))
+ {
+ for (i=key_segs=max_length=0 ; i < keys ; i++)
+ {
+ key_segs+= keydef[i].keysegs;
+ bzero((char*) &keydef[i].block,sizeof(keydef[i].block));
+ for (j=length=0 ; j < keydef[i].keysegs; j++)
+ length+=keydef[i].seg[j].length;
+ keydef[i].length=length;
+ if (length > max_length)
+ max_length=length;
+ }
+ if (!(share = (HP_SHARE*) my_malloc((uint) sizeof(HP_SHARE)+
+ keys*sizeof(HP_KEYDEF)+
+ key_segs*sizeof(HP_KEYSEG),
+ MYF(MY_ZEROFILL))))
+ {
+ pthread_mutex_unlock(&THR_LOCK_heap);
+ DBUG_RETURN(0);
+ }
+ share->keydef=(HP_KEYDEF*) (share+1);
+ keyseg=(HP_KEYSEG*) (share->keydef+keys);
+ init_block(&share->block,reclength+1,min_records,max_records);
+ /* Fix keys */
+ memcpy(share->keydef,keydef,(size_t) (sizeof(keydef[0])*keys));
+ for (i=0 ; i < keys ; i++)
+ {
+ share->keydef[i].seg=keyseg;
+ memcpy(keyseg,keydef[i].seg,
+ (size_t) (sizeof(keyseg[0])*keydef[i].keysegs));
+ keyseg+=keydef[i].keysegs;
+ init_block(&share->keydef[i].block,sizeof(HASH_INFO),min_records,
+ max_records);
+ }
+
+ share->min_records=min_records;
+ share->max_records=max_records;
+ share->data_length=share->index_length=0;
+ share->reclength=reclength;
+ share->blength=1;
+ share->keys=keys;
+ share->max_key_length=max_length;
+ share->changed=0;
+ if (!(share->name=my_strdup(name,MYF(0))))
+ {
+ my_free((gptr) share,MYF(0));
+ pthread_mutex_unlock(&THR_LOCK_heap);
+ DBUG_RETURN(0);
+ }
+#ifdef THREAD
+ thr_lock_init(&share->lock);
+ VOID(pthread_mutex_init(&share->intern_lock,NULL));
+#endif
+ share->open_list.data=(void*) share;
+ heap_share_list=list_add(heap_share_list,&share->open_list);
+ }
+ if (!(info= (HP_INFO*) my_malloc((uint) sizeof(HP_INFO)+
+ share->max_key_length,
+ MYF(MY_ZEROFILL))))
+ {
+ pthread_mutex_unlock(&THR_LOCK_heap);
+ DBUG_RETURN(0);
+ }
+ share->open_count++;
+#ifdef THREAD
+ thr_lock_data_init(&share->lock,&info->lock,NULL);
+#endif
+ info->open_list.data=(void*) info;
+ heap_open_list=list_add(heap_open_list,&info->open_list);
+ pthread_mutex_unlock(&THR_LOCK_heap);
+
+ info->s=share;
+ info->lastkey=(byte*) (info+1);
+ info->mode=mode;
+ info->current_record= (ulong) ~0L; /* No current record */
+ info->current_ptr=0;
+ info->current_hash_ptr=0;
+ info->lastinx= info->errkey= -1;
+ info->update=0;
+#ifndef DBUG_OFF
+ info->opt_flag=READ_CHECK_USED; /* Check when changing */
+#endif
+ DBUG_PRINT("exit",("heap: %lx reclength: %d records_in_block: %d",
+ info,share->reclength,share->block.records_in_block));
+ DBUG_RETURN(info);
+} /* heap_open */
+
+
+ /* map name to a heap-nr. If name isn't found return 0 */
+
+HP_SHARE *_hp_find_named_heap(const char *name)
+{
+ LIST *pos;
+ HP_SHARE *info;
+ DBUG_ENTER("heap_find");
+ DBUG_PRINT("enter",("name: %s",name));
+
+ for (pos=heap_share_list ; pos ; pos=pos->next)
+ {
+ info=(HP_SHARE*) pos->data;
+ if (!strcmp(name,info->name))
+ {
+ DBUG_PRINT("exit",("Old heap_database: %lx",info));
+ DBUG_RETURN(info);
+ }
+ }
+ DBUG_RETURN((HP_SHARE *)0);
+}
+
+
+static void init_block(HP_BLOCK *block, uint reclength, ulong min_records,
+ ulong max_records)
+{
+ uint i,recbuffer,records_in_block;
+
+ max_records=max(min_records,max_records);
+ if (!max_records)
+ max_records=1000; /* As good as quess as anything */
+ recbuffer=(uint) (reclength+sizeof(byte**)-1) & ~(sizeof(byte**)-1);
+ records_in_block=max_records/10;
+ if (records_in_block < 10 && max_records)
+ records_in_block=10;
+ if (!records_in_block || records_in_block*recbuffer >
+ (my_default_record_cache_size-sizeof(HP_PTRS)*HP_MAX_LEVELS))
+ records_in_block=(my_default_record_cache_size-sizeof(HP_PTRS)*
+ HP_MAX_LEVELS)/recbuffer+1;
+ block->records_in_block=records_in_block;
+ block->recbuffer=recbuffer;
+ block->last_allocated= 0L;
+
+ for (i=0 ; i <= HP_MAX_LEVELS ; i++)
+ block->level_info[i].records_under_level=
+ (!i ? 1 : i == 1 ? records_in_block :
+ HP_PTRS_IN_NOD * block->level_info[i-1].records_under_level);
+}